title:
Spontaneous Dynamics of Asymmetric Random Recurrent Spiking Neural
  Networks

abstract:
  We study in this paper the effect of an unique initial stimulation on random
recurrent networks of leaky integrate and fire neurons. Indeed given a
stochastic connectivity this so-called spontaneous mode exhibits various non
trivial dynamics. This study brings forward a mathematical formalism that
allows us to examine the variability of the afterward dynamics according to the
parameters of the weight distribution. Provided independence hypothesis (e.g.
in the case of very large networks) we are able to compute the average number
of neurons that fire at a given time -- the spiking activity. In accordance
with numerical simulations, we prove that this spiking activity reaches a
steady-state, we characterize this steady-state and explore the transients.


title:
Vers un environnement multi personnalites pour la configuration et le
  deploiement d'applications a base de composants logiciels

abstract:
  The multiplication of architecture description languages, component models
and platforms implies a serious dilemma for component based software
architects. On the one hand, they have to choose a language to describe
concrete configurations which will be automatically deployed on execution
platforms. On the other hand, they wish to capitalize their software
architectures independently of any description languages or platforms. To solve
this problem, we propose a multi personalities environment for the
configuration and the deployment of component based applications. This
environment is composed of a core capturing a canonical model of configuration
and deployment, and a set of personalities tailored to languages and platforms.
This paper details the architecture of such an environment and describes the
personalities for the CORBA and Fractal component models.


title: J2EE Deployment: The JOnAS Case Study

abstract:
  La specification J2EE (Java 2 platform Enterprise Edition) definit une
architecture de serveur d'application Java. Jusqu'a J2EE 1.3, seuls les aspects
de deploiement concernant le developpeur d'applications etaient adresses. Avec
J2EE 1.4, les interfaces et les etapes de deploiement ont ete plus precisement
specifiees dans la specification "J2EE Deployment". JOnAS (Java Open
Application Server) est une plate-forme J2EE developpee au sein du consortium
ObjectWeb. Les aspects deploiement sont en cours de developpement. Cet article
decrit les concepts lies au deploiement dans J2EE, ainsi que les problematiques
levees lors de leur mise en oeuvre pour JOnAS. Il n'a pas pour but de presenter
un travail abouti, mais illustre le deploiement par un cas concret et ebauche
une liste de besoins non encore satisfaits dans le domaine.
  -----
  The J2EE (Java 2 platform Enterprise Edition) specification defines an
architecture for Java Application Servers. Until J2EE 1.3, the deployment
aspect was addressed from the developer point of view only. Since J2EE 1.4,
deployment APIs and steps have been more precisely specified within the "J2EE
Deployment Specification". JOnAS (Java Open Application Server) is a J2EE
platform implementation by ObjectWeb. The deployment aspects are under
development. This article describes the J2EE Deployment concepts, and the
issues raised when implementing deployment features within JOnAS. It does not
provide a complete solution, but illustrates deployment through a concrete
example and initiates a list of non fulfilled requirements.


title:
SDS : Une infrastructure d'installation de logiciels libres pour des
  organisations multi-sites

abstract:
  Les developpements logiciels sur les systemes UNIX font de plus en plus appel
aux logiciels libres. Nous proposons une solution de deploiement et de controle
de ces logiciels libres au sein d'une grande organisation. Nous nous attachons
particulierement a resoudre les problemes lies au deploiement multi-sites ainsi
qu'a la gestion de configuration de ces deploiements. L'originalite de notre
approche repose sur sa capacite a etre mise en oeuvre et controlee par les
utilisateurs plutot que par les administrateurs, sans necessiter d'expertise
particuliere, et par les possibilites de deploiement dans des environnements
heterogenes.
  -----
  Free and open source software is more and more used for software developments
on UNIX systems. We are proposing a solution to control the deployment of free
software in the context of a large corporation, focusing on multi-site
deployment and configuration management. The originality of our approach rests
on its ability to be implemented and controlled by users rather than
administrators, without requiring any particular expertise, and on its facility
to be deployed in heterogeneous environments.


title: Adaptation dynamique de services

abstract:
  This paper proposes a software architecture for dynamical service adaptation.
The services are constituted by reusable software components. The adaptation's
goal is to optimize the service function of their execution context. For a
first step, the context will take into account just the user needs but other
elements will be added. A particular feature in our proposition is the profiles
that are used not only to describe the context's elements but also the
components itself. An Adapter analyzes the compatibility between all these
profiles and detects the points where the profiles are not compatibles. The
same Adapter search and apply the possible adaptation solutions: component
customization, insertion, extraction or replacement.


title: Runtime Reconfiguration of J2EE Applications

abstract:
  Runtime reconfiguration considered as "applying required changes to a running
system" plays an important role for providing high availability not only of
safety- and mission-critical systems, but also for commercial web-applications
offering professional services. Hereby, the main concerns are maintaining the
consistency of the running system during reconfiguration and minimizing its
down-time caused by the reconfiguration. This paper focuses on the platform
independent subsystem that realises deployment and redeployment of J2EE modules
based on the new J2EE Deployment API as a part of the implementation of our
proposed system architecture enabling runtime reconfiguration of
component-based systems. Our "controlled runtime redeployment" comprises an
extension of hot deployment and dynamic reloading, complemented by allowing for
structural change


title: Deployment in dynamic environments

abstract:
  Information and communication technologies are moving towards a new stage
where applications will be dynamically deployed, uninstalled, updated and
(re)configured. Several approaches have been followed with the goal of creating
a fully automated and context-aware deployment system. Ideally, this system
should be capable of handling the dynamics of this new situation, without
losing sight of other factors, such as performance, security, availability or
scalability. We will take some of the technologies that follow the principles
of Service Oriented Architectures, SOA, as a paradigm of dynamic environments.
SOA promote the breaking down of applications into sets of loosely coupled
elements, called services. Services can be dynamically bound, deployed,
reconfigured, uninstalled and updated. First of all, we will try to offer a
broad view on the specific deployment issues that arise in these environments.
Later on, we will present our approach to the problem. One of the essential
points that has to be tackled to develop an automated deployment engine will be
to have enough information to carry out tasks without human intervention. In
the article we will focus on the format and contents of deployment descriptors.
Additionally, we will go into the details of the deployment framework for OSGi
enabled gateways that has been developed by our research group. Finally we will
give some concluding remarks and some ideas for future work


title:
OpenCCM : une infrastructure a composants pour le deploiement
  d'applications a base de composants CORBA

abstract:
  Deployment of software components for building distributed applications
consists of the coordination of a set of basic tasks like uploading component
binaries to the execution sites, loading them in memory, instantiating
components, interconnecting their ports, setting their business and technical
attributes. The automation of the deployment process then requires the presence
of a software infrastructure distributed itself on the different execution
sites. This paper presents the characteristics of such an infrastructure for
the deployment of CORBA component-based applications. This latter is designed
and implemented in the context of our OpenCCM platform, an open source
implementation of the CORBA Component Model. The main characteristic lays on
the fact that this infrastructure is itself designed as a set of CORBA
component assemblies. This allows its dynamic assembly during its deployment
over the execution sites


title: Gestion du deploiement de composants sur reseau P2P

abstract:
  The deployment of component-based applications relies on a centralized
directory to store the components. This paper describes an approach to
distribute software components to be deployed on a set of peers of a peer to
peer network in order to exploit some associated characteristics (load
balancing, fault-tolerance, self-organisation). The proposed architecture is
situated in the context of OSGI application deployment management. The software
components (bundles) are distributed among a set of nodes participating in the
execution of services. When a node wants to install a component which is not
deployed locally, the component is looked for and installed using a p2p
network.
  -----
  Le deploiement d'applications a composants repose sur une approche d'annuaire
centralise de stockage des composants. Cet article decrit une approche pour
distribuer les composants logiciels a deployer sur un ensemble de noeuds d'un
reseau pair-a-pair afin de pouvoir exploiter certaines caracteristiques
associees (equilibrage de charge, tolerance de panne, auto-organisation).
L'architecture proposee entre dans le cadre de la gestion du deploiement
d'applications sur le modele OSGi. Les composants logiciels (ou bundles) sont
repartis a travers un ensemble de noeuds participant a l'execution de services.
Lorsqu'un noeud veut installer un composant et si celui-ci n'est pas encore
deploye localement, il est recherche et installe en utilisant un reseau p2p


title:
Un meta-modele pour l'automatisation du deploiement d'applications
  logicielles

abstract:
  Le deploiement est maintenant considere comme une activite a part entiere du
cycle de vie du logiciel. Les grandes entreprises souhaitent pouvoir
automatiser cette etape tout en prenant en compte les caracteristiques de
chaque machine cible. Pour repondre a ces besoins, nous avons defini un
environnement de deploiement : ORYA (Open enviRonment to deploY Applications).
Cet environnement utilise un meta-modele de deploiement, decrit dans ce papier.
Notre approche utilise aussi les technologies des federations et des procedes,
fournissant un environnement flexible et extensible pour l'utilisateur.
  -----
  The deployment is now a full activity of the software lifecycle. Large
enterprises want to automate this step, taking into account characteristics of
each target machine. To satisfy these needs, we have defined an environment for
the deployment phase: ORYA (Open enviRonment to deploY Applications). This
environment uses a deployment metamodel, described in this paper. Our approach
is based also on federation and process federations, providing a flexible and
extensible environment to the user


title: FROGi : Deploiement de composants Fractal sur OSGi

abstract:
  Cet article presente FROGi, une proposition visant a introduire le modele a
composants Fractal a l'interieur de la plateforme de services OSGi. La
motivation derriere ce travail est double. D'un cote, FROGi offre aux
developpeurs de services OSGi un modele a composants extensibles qui facilite
le developpement des bundles ; ces derniers restent toutefois compatibles avec
les bundles "patrimoniaux". D'un autre cote, FROGi beneficie de
l'infrastructure de deploiement que represente OSGi et qui facilite la
realisation du conditionnement et du deploiement de composants Fractal. Dans
FROGi, une application Fractal est conditionnee sous la forme d'un ou plusieurs
bundles et elle peut etre deployee de facon partielle et les activites de
deploiement peuvent avoir lieu de facon continue.
  -- This paper presents FROGi, a proposal to introduce the Fractal component
model into the OSGi services platform. There are two motivations for this work.
The first one is to offer a flexible component model to the OSGi developers to
simplify bundle development. Bundles developed with FROGi are nevertheless
compatible with standard bundles. The second motivation is to leverage OSGi's
deployment capabilities to package and deploy Fractal components. In FROGi, a
Fractal application is packaged and delivered as a set of OSGi bundles; such an
application supports partial deployment and additionally, deployment activities
can occur continuously.


title:
From Tensor Equations to Numerical Code -- Computer Algebra Tools for
  Numerical Relativity

abstract:
  In this paper we present our recent work in developing a computer-algebra
tool for systems of partial differential equations (PDEs), termed "Kranc". Our
work is motivated by the problem of finding solutions of the Einstein equations
through numerical simulations. Kranc consists of Mathematica based
computer-algebra packages, that facilitate the task of dealing with symbolic
tensorial calculations and realize the conversion of systems of partial
differential evolution equations into parallelized C or Fortran code.


title: Lower-Stretch Spanning Trees

abstract:
  We prove that every weighted graph contains a spanning tree subgraph of
average stretch O((log n log log n)^2). Moreover, we show how to construct such
a tree in time O(m log^2 n).


title:
An Evaluated Certification Services System for the German National Root
  CA - Legally Binding and Trustworthy Transactions in E-Business and
  E-Government

abstract:
  National Root CAs enable legally binding E-Business and E-Government
transactions. This is a report about the development, the evaluation and the
certification of the new certification services system for the German National
Root CA. We illustrate why a new certification services system was necessary,
and which requirements to the new system existed. Then we derive the tasks to
be done from the mentioned requirements. After that we introduce the initial
situation at the beginning of the project. We report about the very process and
talk about some unfamiliar situations, special approaches and remarkable
experiences. Finally we present the ready IT system and its impact to
E-Business and E-Government.


title: Using LDAP Directories for Management of PKI Processes

abstract:
  We present a framework for extending the functionality of LDAP servers from
their typical use as a public directory in public key infrastructures. In this
framework the LDAP servers are used for administrating infrastructure
processes. One application of this framework is a method for providing
proof-of-possession, especially in the case of encryption keys. Another one is
the secure delivery of software personal security environments.


title: Towards a Flexible Intra-Trustcenter Management Protocol

abstract:
  This paper proposes the Intra Trustcenter Protocol (ITP), a flexible and
secure management protocol for communication between arbitrary trustcenter
components. Unlike other existing protocols (like PKCS#7, CMP or XKMS) ITP
focuses on the communication within a trustcenter. It is powerful enough for
transferring complex messages which are machine and human readable and easy to
understand. In addition it includes an extension mechanism to be prepared for
future developments.


title: Planning for Directory Services in Public Key Infrastructures

abstract:
  In this paper we provide a guide for public key infrastructure designers and
administrators when planning for directory services. We concentrate on the LDAP
directories and how they can be used to successfully publish PKI information.
We analyse their available mechanisms and propose a best practice guide for use
in PKI. We then take a look into the German Signature Act and Ordinance and
discuss their part as far as directories concerning. Finally, we translate
those to the LDAP directories practices.


title: CDN: Content Distribution Network

abstract:
  Internet evolves and operates largely without a central coordination, the
lack of which was and is critically important to the rapid growth and evolution
of Internet. However, the lack of management in turn makes it very difficult to
guarantee proper performance and to deal systematically with performance
problems. Meanwhile, the available network bandwidth and server capacity
continue to be overwhelmed by the skyrocketing Internet utilization and the
accelerating growth of bandwidth intensive content. As a result, Internet
service quality perceived by customers is largely unpredictable and
unsatisfactory. Content Distribution Network (CDN) is an effective approach to
improve Internet service quality. CDN replicates the content from the place of
origin to the replica servers scattered over the Internet and serves a request
from a replica server close to where the request originates. In this paper, we
first give an overview about CDN. We then present the critical issues involved
in designing and implementing an effective CDN and survey the approaches
proposed in literature to address these problems. An example of CDN is
described to show how a real commercial CDN operates. After this, we present a
scheme that provides fast service location for peer-to-peer systems, a special
type of CDN with no infrastructure support. We conclude with a brief projection
about CDN.


title: Data Path Processing in Fast Programmable Routers

abstract:
  Internet is growing at a fast pace. The link speeds are surging toward 40
Gbps with the emergence of faster link technologies. New applications are
coming up which require intelligent processing at the intermediate routers.
Switches and routers are becoming the bottlenecks in fast communication. On one
hand faster links deliver more packets every second and on the other hand
intelligent processing consumes more CPU cycles at the router. The conflicting
goals of providing faster but computationally expensive processing call for new
approaches in designing routers.
  This survey takes a look at the core functionalities, like packet
classification, buffer memory management, switch scheduling and output link
scheduling performed by a router in its data path processing and discusses the
algorithms that aim to reduce the performance bound for these operations. An
important requirement for the routers is to provide Quality of Service
guarantees. We propose an algorithm to guarantee QoS in Input Queued Routers.
The hardware solution to speed up router operation was Application Specific
Integrated Circuits (ASICs). But the inherent inflexibility of the method is a
demerit as network standards and application requirements are constantly
evolving, which seek a faster turnaround time to keep up with the changes. The
promise of Network Processors (NP) is the flexibility of general-purpose
processors together with the speed of ASICs. We will study the architectural
choices for the design of Network Processors and focus on some of the
commercially available NPs. There is a plethora of NP vendors in the market.
The discussion on the NP benchmarks sets the normalizing platform to evaluate
these NPs.


title: Comparing Multi-Target Trackers on Different Force Unit Levels

abstract:
  Consider the problem of tracking a set of moving targets. Apart from the
tracking result, it is often important to know where the tracking fails, either
to steer sensors to that part of the state-space, or to inform a human operator
about the status and quality of the obtained information. An intuitive quality
measure is the correlation between two tracking results based on uncorrelated
observations. In the case of Bayesian trackers such a correlation measure could
be the Kullback-Leibler difference.
  We focus on a scenario with a large number of military units moving in some
terrain. The units are observed by several types of sensors and "meta-sensors"
with force aggregation capabilities. The sensors register units of different
size. Two separate multi-target probability hypothesis density (PHD) particle
filters are used to track some type of units (e.g., companies) and their
sub-units (e.g., platoons), respectively, based on observations of units of
those sizes. Each observation is used in one filter only.
  Although the state-space may well be the same in both filters, the posterior
PHD distributions are not directly comparable -- one unit might correspond to
three or four spatially distributed sub-units. Therefore, we introduce a
mapping function between distributions for different unit size, based on
doctrine knowledge of unit configuration.
  The mapped distributions can now be compared -- locally or globally -- using
some measure, which gives the correlation between two PHD distributions in a
bounded volume of the state-space. To locate areas where the tracking fails, a
discretized quality map of the state-space can be generated by applying the
measure locally to different parts of the space.


title: Extremal optimization for sensor report pre-processing

abstract:
  We describe the recently introduced extremal optimization algorithm and apply
it to target detection and association problems arising in pre-processing for
multi-target tracking.
  Here we consider the problem of pre-processing for multiple target tracking
when the number of sensor reports received is very large and arrives in large
bursts. In this case, it is sometimes necessary to pre-process reports before
sending them to tracking modules in the fusion system. The pre-processing step
associates reports to known tracks (or initializes new tracks for reports on
objects that have not been seen before). It could also be used as a pre-process
step before clustering, e.g., in order to test how many clusters to use.
  The pre-processing is done by solving an approximate version of the original
problem. In this approximation, not all pair-wise conflicts are calculated. The
approximation relies on knowing how many such pair-wise conflicts that are
necessary to compute. To determine this, results on phase-transitions occurring
when coloring (or clustering) large random instances of a particular graph
ensemble are used.


title: Geographic Routing with Limited Information in Sensor Networks

abstract:
  Geographic routing with greedy relaying strategies have been widely studied
as a routing scheme in sensor networks. These schemes assume that the nodes
have perfect information about the location of the destination. When the
distance between the source and destination is normalized to unity, the
asymptotic routing delays in these schemes are $\Theta(\frac{1}{M(n)}),$ where
M(n) is the maximum distance traveled in a single hop (transmission range of a
radio). In this paper, we consider routing scenarios where nodes have location
errors (imprecise GPS), or where only coarse geographic information about the
destination is available, and only a fraction of the nodes have routing
information. We show that even with such imprecise or limited
destination-location information, the routing delays are
$\Theta(\frac{1}{M(n)})$. We also consider the throughput-capacity of networks
with progressive routing strategies that take packets closer to the destination
in every step, but not necessarily along a straight-line. We show that the
throughput-capacity with progressive routing is order-wise the same as the
maximum achievable throughput-capacity.


title:
Building Chinese Lexicons from Scratch by Unsupervised Short Document
  Self-Segmentation

abstract:
  Chinese text segmentation is a well-known and difficult problem. On one side,
there is not a simple notion of "word" in Chinese language making really hard
to implement rule-based systems to segment written texts, thus lexicons and
statistical information are usually employed to achieve such a task. On the
other side, any piece of Chinese text usually includes segments present neither
in the lexicons nor in the training data. Even worse, such unseen sequences can
be segmented into a number of totally unrelated words making later processing
phases difficult. For instance, using a lexicon-based system the sequence
???(Baluozuo, Barroso, current president-designate of the European Commission)
can be segmented into ?(ba, to hope, to wish) and ??(luozuo, an undefined word)
changing completely the meaning of the sentence. A new and extremely simple
algorithm specially suited to work over short Chinese documents is introduced.
This new algorithm performs text "self-segmentation" producing results
comparable to those achieved by native speakers without using either lexicons
or any statistical information beyond the obtained from the input text.
Furthermore, it is really robust for finding new "words", especially proper
nouns, and it is well suited to build lexicons from scratch. Some preliminary
results are provided in addition to examples of its employment.


title: A Self-Reconfigurable Computing Platform Hardware Architecture

abstract:
  Field Programmable Gate Arrays (FPGAs) have recently been increasingly used
for highly-parallel processing of compute intensive tasks. This paper
introduces an FPGA hardware platform architecture that is PC-based, allows for
fast reconfiguration over the PCI bus, and retains a simple physical hardware
design. The design considerations are first discussed, then the resulting
system architecture designed is illustrated. Finally, experimental results on
the FPGA resources utilized for this design are presented.


title:
Lower bounds on the Deterministic and Quantum Communication Complexity
  of Hamming Distance

abstract:
  Alice and Bob want to know if two strings of length n are almost equal. That
is, do they differ on \textit{at most} a bits? Let 0\leq a\leq n-1. We show
that any deterministic protocol, as well as any error-free quantum protocol (C*
version), for this problem requires at least n-2 bits of communication. We show
the same bounds for the problem of determining if two strings differ in exactly
a bits. We also prove a lower bound of n/2-1 for error-free Q* quantum
protocols. Our results are obtained by lower-bounding the ranks of the
appropriate matrices.


title: Transparent Format Migration of Preserved Web Content

abstract:
  The LOCKSS digital preservation system collects content by crawling the web
and preserves it in the format supplied by the publisher. Eventually, browsers
will no longer understand that format. A process called format migration
converts it to a newer format that the browsers do understand. The LOCKSS
program has designed and tested an initial implementation of format migration
for Web content that is transparent to readers, building on the content
negotiation capabilities of HTTP.


title: Notes On The Design Of An Internet Adversary

abstract:
  The design of the defenses Internet systems can deploy against attack,
especially adaptive and resilient defenses, must start from a realistic model
of the threat. This requires an assessment of the capabilities of the
adversary. The design typically evolves through a process of simulating both
the system and the adversary. This requires the design and implementation of a
simulated adversary based on the capability assessment. Consensus on the
capabilities of a suitable adversary is not evident. Part of the recent
redesign of the protocol used by peers in the LOCKSS digital preservation
system included a conservative assessment of the adversary's capabilities. We
present our assessment and the implications we drew from it as a step towards a
reusable adversary specification.


title:
Supporting Bandwidth Guarantee and Mobility for Real-Time Applications
  on Wireless LANs

abstract:
  The proliferation of IEEE 802.11-based wireless LANs opens up avenues for
creation of several tetherless and mobility oriented services. Most of these
services, like voice over WLAN, media streaming etc., generate delay and
bandwidth sensitive traffic. These traffic flows require undisrupted network
connectivity with some QoS guarantees. Unfortunately, there is no adequate
support built into these wireless LANs towards QoS provisioning. Further, the
network layer handoff latency incurred by mobile nodes in these wireless LANs
is too high for real-time applications to function properly. In this paper, we
describe a QoS mechanism, called Rether, to effectively support bandwidth
guarantee on wireless LANs. Rether is designed to support the current wireless
LAN technologies like 802.11b and 802.11a with a specific capability of being
tailored for QoS oriented technology like 802.11e. We also describe a
low-latency handoff mechanism which expedites network level handoff to provide
real-time applications with an added advantage of seamless mobility.


title:
Modeling the input history of programs for improved instruction-memory
  performance

abstract:
  When a program is loaded into memory for execution, the relative position of
its basic blocks is crucial, since loading basic blocks that are unlikely to be
executed first places them high in the instruction-memory hierarchy only to be
dislodged as the execution goes on. In this paper we study the use of Bayesian
networks as models of the input history of a program. The main point is the
creation of a probabilistic model that persists as the program is run on
different inputs and at each new input refines its own parameters in order to
reflect the program's input history more accurately. As the model is thus
tuned, it causes basic blocks to be reordered so that, upon arrival of the next
input for execution, loading the basic blocks into memory automatically takes
into account the input history of the program. We report on extensive
experiments, whose results demonstrate the efficacy of the overall approach in
progressively lowering the execution times of a program on identical inputs
placed randomly in a sequence of varied inputs. We provide results on selected
SPEC CINT2000 programs and also evaluate our approach as compared to the gcc
level-3 optimization and to Pettis-Hansen reordering.


title:
Reconfigurations dynamiques de services dans un intergiciel a composants
  CORBA CCM

abstract:
  Today, component oriented middlewares are used to design, develop and deploy
easily distributed applications, by ensuring the heterogeneity,
interoperability, and reuse of the software modules, and the separation between
the business code encapsulated in the components and the system code managed by
the containers. Several standards answer this definition such as: CCM (CORBA
Component Model), EJB (Enterprise Java Beans) and .Net. However these standards
offer a limited and fixed number of system services, removing any possibility
to add system services or to reconfigure dynamically the middleware. Our works
propose mechanisms to add and to adapt dynamically the system services, based
on a reconfiguration language which is dynamically adaptable to the need of the
reconfiguration, and on a tool of dynamic reconfiguration, a prototype was
achieved for the OpenCCM platform, that is an implementation of the CCM
specification. This work was partially financed by the european project
IST-COACH (2001-34445).


title:
Support pour la reconfiguration d'implantation dans les applications a
  composants Java

abstract:
  Nowadays, numerous component models are used for various purposes: to build
applications, middleware or even operating systems. Those models commonly
support structure reconfiguration, that is modification of application's
architecture at runtime. On the other hand, very few allow implementation
reconfiguration, that is runtime modification of the code of components
building the application. In this article we present the work we performed on
JULIA, a Java-based implementation of the FRACTAL component model, in order for
it to support implementation reconfigurations. We show how we overcame the
limitations of Java class loading mechanism to allow runtime modifications of
components' implementation and interfaces. We also describe the integration of
our solution with the JULIA ADL.


title:
Contractualisation des ressources pour le deploiement des composants
  logiciels

abstract:
  Software deployment can turn into a baffling problem when the components
being deployed exhibit non-functional requirements. If the platform on which
such components are deployed cannot satisfy their non-functional requirements,
then they may in turn fail to perform satisfactorily. In this paper, we present
a contract-based approach to take a specific category of non-functional
properties specified by components into account, that is those that pertain to
the resources that are necessary for their execution.


title: Gestion transactionnelle de la reprise sur erreurs dans le deploiement

abstract:
  With the development of the networks and the Internet, the problems of
automated deployment on broad scale became increasingly crucial. Software
deployment is a complex process covering several activities going from the
configuration to the retirement of a software product. During the execution of
a deployment process, exceptions can be met which put the site in an incoherent
state. To solve them, we propose an approach based on transactional concepts
which describes the actions to be undertaken when an exceptional situation is
met during the deployment process. The approach guaranties the respect of the
site's consistency by preserving part of the work already carried out by the
process. This article presents our approach and an experimentation made in an
academic deployment system.


title:
Deploiement d'ordonnanceurs de processus specifiques dans un systeme
  d'exploitation generaliste

abstract:
  Bossa is a framework to develop new processes schedulers in commodity
operating systems. Although Bossa enables fine-grained management of the
processor through new scheduling policies, deploying an application with its
own scheduler raises some problems. In this paper we study the problems caused
when deploying an application and its scheduler and to adresse these, we
propose to establish Quality of Service contracts and mechanisms to reconfigure
the scheduler hierarchy.


title:
A Software Architecture for Automatic Deployment of CORBA Components
  Using Grid Technologies

abstract:
  Software components turn out to be a convenient model to build complex
applications for scientific computing and to run them on a computational grid.
However, deploying complex, component-based applications in a grid environment
is particularly arduous. To prevent the user from directly dealing with a large
number of execution hosts and their heterogeneity within a grid, the
application deployment phase must be as automatic as possible. This paper
describes an architecture for automatic deployment of component-based
applications on computational grids. In the context of the CORBA Component
Model (CCM), this paper details all the steps to achieve an automatic
deployment of components as well as the entities involved: a grid access
middleware and its grid information service (like OGSI), a component deployment
model, as specified by CCM, an enriched application description and a
deployment planner in order to select resources and map components onto
computers.


title:
Pandora : une plate-forme efficace pour la construction d'applications
  autonomes

abstract:
  Autonomic computing has been proposed recently as a way to address the
difficult management of applications whose complexity is constantly increasing.
Autonomous applications will have to be especially flexible and be able to
monitor themselves permanently. This work presents a framework, Pandora, which
eases the construction of applications that satisfy this double goal. Pandora
relies on an original application programming pattern - based on stackable
layers and message passing - to obtain minimalist model and architecture that
allows to control the overhead imposed by the full reflexivity of the
framework. Besides, a prototype of the framework has been implemented in C++. A
detailed performance study, together with examples of use, complement this
presentation


title: Des correctifs de securite a la mise a jour

abstract:
  The ever growing software complexity suggests that they will never be bugfree
and therefore secure. Software compagnies regulary publish updates. But maybe
because of lack of time or care or maybe because stopping application is
annoying, such updates are rarely if ever deployed on users' machines. We
propose an integrated tool allowing system administrators to deploy critical
security updates on the fly on applications running remotly without end-user
intervention. Our approach is based on an aspect weaving system, Arachne, that
dynamicaly rewrites binary code. Hence updated applications are still running
while they are updated. Our second tool Minerve integrates Arachne within the
standart updating process: Minerve takes a patch produced by dif and eventually
builds a dynamic patch that can later be woven to update the application on the
fly. In addition, Minerve allows to consult patches translated in a dedicated
language and hence eases auditing tasks.


title: Gestion Dynamique des Services Techniques pour Modele a Composants

abstract:
  The new applications being intended for more and more heterogeneous
environments, it is necessary to propose solutions of development which answer
in best the necessities of adaptation of new services. Component-based
programming partially answers this aim, allowing easy replacement of software
blocks in order to provide the most adapted version of a component.
Nevertheless, most of the industrial component-based model implementations do
not allow to provide to components the most adapted technical services (naming,
trading, security, transaction, etc.). In this paper, we suggest defining
technical services themselves under the shape of components. We shall detail
our proposition, by basing it on the Fractal component model of Objectweb.
Then, we shall bring solutions for the use of these new component-based
technical services and shall propose a set of management components which allow
to administer in a dynamic and stand-alone way the obtained components. Finally
we present the prototype of the proposed solution.


title:
Local heuristics and the emergence of spanning subgraphs in complex
  networks

abstract:
  We study the use of local heuristics to determine spanning subgraphs for use
in the dissemination of information in complex networks. We introduce two
different heuristics and analyze their behavior in giving rise to spanning
subgraphs that perform well in terms of allowing every node of the network to
be reached, of requiring relatively few messages and small node bandwidth for
information dissemination, and also of stretching paths with respect to the
underlying network only modestly. We contribute a detailed mathematical
analysis of one of the heuristics and provide extensive simulation results on
random graphs for both of them. These results indicate that, within certain
limits, spanning subgraphs are indeed expected to emerge that perform well in
respect to all requirements. We also discuss the spanning subgraphs' inherent
resilience to failures and adaptability to topological changes.


title: Principles for Digital Preservation

abstract:
  The immense investments in creating and disseminating digitally represented
information have not been accompanied by commensurate effort to ensure the
longevity of information of permanent interest. Asserted difficulties with
long-term digital preservation prove to be largely underestimation of what
technology can provide. We show how to clarify prominent misunderstandings and
sketch a 'Trustworthy Digital Object (TDO)' method that solves all the
published technical challenges.


title:
Trustworthy 100-Year Digital Objects: Durable Encoding for When It's Too
  Late to Ask

abstract:
  How can an author store digital information so that it will be reliably
useful, even years later when he is no longer available to answer questions?
Methods that might work are not good enough; what is preserved today should be
reliably useful whenever someone wants it. Prior proposals fail because they
confound saved data with irrelevant details of today's information
technology--details that are difficult to define, extract, and save completely
and accurately.
  We use a virtual machine to represent and eventually to render any data
whatsoever. We focus on a case of intermediate difficulty--an executable
procedure--and identify a variant for every other data type. This solution
might be more elaborate than needed to render some text, image, audio, or video
data. Simple data can be preserved as representations using well-known
standards. We sketch practical methods for files ranging from simple structures
to those containing computer programs, treating simple cases here and deferring
complex cases for future work. Enough of the complete solution is known to
enable practical aggressive preservation programs today.


title: Forbidden Subgraphs in Connected Graphs

abstract:
  Given a set $\xi=\{H_1,H_2,...\}$ of connected non acyclic graphs, a
$\xi$-free graph is one which does not contain any member of $% \xi$ as copy.
Define the excess of a graph as the difference between its number of edges and
its number of vertices. Let ${\gr{W}}_{k,\xi}$ be theexponential generating
function (EGF for brief) of connected $\xi$-free graphs of excess equal to $k$
($k \geq 1$). For each fixed $\xi$, a fundamental differential recurrence
satisfied by the EGFs ${\gr{W}}_{k,\xi}$ is derived. We give methods on how to
solve this nonlinear recurrence for the first few values of $k$ by means of
graph surgery. We also show that for any finite collection $\xi$ of non-acyclic
graphs, the EGFs ${\gr{W}}_{k,\xi}$ are always rational functions of the
generating function, $T$, of Cayley's rooted (non-planar) labelled trees. From
this, we prove that almost all connected graphs with $n$ nodes and $n+k$ edges
are $\xi$-free, whenever $k=o(n^{1/3})$ and $|\xi| < \infty$ by means of
Wright's inequalities and saddle point method. Limiting distributions are
derived for sparse connected $\xi$-free components that are present when a
random graph on $n$ nodes has approximately $\frac{n}{2}$ edges. In particular,
the probability distribution that it consists of trees, unicyclic components,
$...$, $(q+1)$-cyclic components all $\xi$-free is derived. Similar results are
also obtained for multigraphs, which are graphs where self-loops and
multiple-edges are allowed.


title:
On the existence of truly autonomic computing systems and the link with
  quantum computing

abstract:
  A theoretical model of truly autonomic computing systems (ACS), with
infinitely many constraints, is proposed. An argument similar to Turing's for
the unsolvability of the halting problem, which is permitted in classical
logic, shows that such systems cannot exist. Turing's argument fails in the
recently proposed non-Aristotelian finitary logic (NAFL), which permits the
existence of ACS. NAFL also justifies quantum superposition and entanglement,
which are essential ingredients of quantum algorithms, and resolves the
Einstein-Podolsky-Rosen (EPR) paradox in favour of quantum mechanics and
non-locality. NAFL requires that the autonomic manager (AM) must be
conceptually and architecturally distinct from the managed element, in order
for the ACS to exist as a non-self-referential entity. Such a scenario is
possible if the AM uses quantum algorithms and is protected from all problems
by (unbreakable) quantum encryption, while the managed element remains
classical. NAFL supports such a link between autonomic and quantum computing,
with the AM existing as a metamathematical entity. NAFL also allows quantum
algorithms to access truly random elements and thereby supports non-standard
models of quantum (hyper-) computation that permit infinite parallelism.


title: Embeddings into the Pancake Interconnection Network

abstract:
  Owing to its nice properties, the pancake is one of the Cayley graphs that
were proposed as alternatives to the hypercube for interconnecting processors
in parallel computers. In this paper, we present embeddings of rings, grids and
hypercubes into the pancake with constant dilation and congestion. We also
extend the results to similar efficient embeddings into the star graph.


title: Inter-Package Dependency Networks in Open-Source Software

abstract:
  This research analyzes complex networks in open-source software at the
inter-package level, where package dependencies often span across projects and
between development groups. We review complex networks identified at ``lower''
levels of abstraction, and then formulate a description of interacting software
components at the package level, a relatively ``high'' level of abstraction. By
mining open-source software repositories from two sources, we empirically show
that the coupling of modules at this granularity creates a small-world and
scale-free network in both instances.


title: Deterministic Bayesian Logic

abstract:
  In this paper a conditional logic is defined and studied. This conditional
logic, Deterministic Bayesian Logic, is constructed as a deterministic
counterpart to the (probabilistic) Bayesian conditional. The logic is
unrestricted, so that any logical operations are allowed. This logic is shown
to be non-trivial and is not reduced to classical propositions. The Bayesian
conditional of DBL implies a definition of logical independence. Interesting
results are derived about the interactions between the logical independence and
the proofs. A model is constructed for the logic. Completeness results are
proved. It is shown that any unconditioned probability can be extended to the
whole logic DBL. The Bayesian conditional is then recovered from the
probabilistic DBL. At last, it is shown why DBL is compliant with Lewis
triviality.


title: On the High-SNR Capacity of Non-Coherent Networks

abstract:
  We obtain the first term in the high signal-to-noise ratio (SNR) expansion of
the capacity of fading networks where the transmitters and receivers--while
fully cognizant of the fading \emph{law}--have no access to the fading
\emph{realization}. This term is an integer multiple of $\log \log
\textnormal{SNR}$ with the coefficient having a simple combinatorial
characterization.


title: A Note on the PAC Bayesian Theorem

abstract:
  We prove general exponential moment inequalities for averages of [0,1]-valued
iid random variables and use them to tighten the PAC Bayesian Theorem. The
logarithmic dependence on the sample count in the enumerator of the PAC
Bayesian bound is halved.


title: A Decidable Probability Logic for Timed Probabilistic Systems

abstract:
  In this paper we extend the predicate logic introduced in [Beauquier et al.
2002] in order to deal with Semi-Markov Processes. We prove that with respect
to qualitative probabilistic properties, model checking is decidable for this
logic applied to Semi-Markov Processes. Furthermore we apply our logic to
Probabilistic Timed Automata considering classical and urgent semantics, and
considering also predicates on clock. We prove that results on Semi Markov
Processes hold also for Probabilistic Timed Automata for both the two semantics
considered. Moreover, we prove that results for Markov Processes shown in
[Beauquier et al. 2002] are extensible to Probabilistic Timed Automata where
urgent semantics is considered.


title: EURYDICE : A platform for unified access to documents

abstract:
  In this paper we present Eurydice, a platform dedicated to provide a unified
gateway to documents. Its basic functionalities about collecting documents have
been designed based on a long experience about the management of scientific
documentation among large and demanding academic communities such as IMAG and
INRIA. Besides the basic problem of accessing documents - which was of course
the original and main motivation of the project - a great effort has been
dedicated to the development of management functionalities which could help
institutions to control, analyse the current situation about the use of the
documentation, and finally to set a better ground for a documentation policy.
Finally a great emphasis - and corresponding technical investment - has been
put on the protection of property and reproduction rights both from the users'
intitution side and from the editors' side.


title: Ranking Pages by Topology and Popularity within Web Sites

abstract:
  We compare two link analysis ranking methods of web pages in a site. The
first, called Site Rank, is an adaptation of PageRank to the granularity of a
web site and the second, called Popularity Rank, is based on the frequencies of
user clicks on the outlinks in a page that are captured by navigation sessions
of users through the web site. We ran experiments on artificially created web
sites of different sizes and on two real data sets, employing the relative
entropy to compare the distributions of the two ranking methods. For the real
data sets we also employ a nonparametric measure, called Spearman's footrule,
which we use to compare the top-ten web pages ranked by the two methods. Our
main result is that the distributions of the Popularity Rank and Site Rank are
surprisingly close to each other, implying that the topology of a web site is
very instrumental in guiding users through the site. Thus, in practice, the
Site Rank provides a reasonable first order approximation of the aggregate
behaviour of users within a web site given by the Popularity Rank.


title:
Mining Heterogeneous Multivariate Time-Series for Learning Meaningful
  Patterns: Application to Home Health Telecare

abstract:
  For the last years, time-series mining has become a challenging issue for
researchers. An important application lies in most monitoring purposes, which
require analyzing large sets of time-series for learning usual patterns. Any
deviation from this learned profile is then considered as an unexpected
situation. Moreover, complex applications may involve the temporal study of
several heterogeneous parameters. In that paper, we propose a method for mining
heterogeneous multivariate time-series for learning meaningful patterns. The
proposed approach allows for mixed time-series -- containing both pattern and
non-pattern data -- such as for imprecise matches, outliers, stretching and
global translating of patterns instances in time. We present the early results
of our approach in the context of monitoring the health status of a person at
home. The purpose is to build a behavioral profile of a person by analyzing the
time variations of several quantitative or qualitative parameters recorded
through a provision of sensors installed in the home.


title: Finding Approximate Palindromes in Strings Quickly and Simply

abstract:
  Described are two algorithms to find long approximate palindromes in a
string, for example a DNA sequence. A simple algorithm requires O(n)-space and
almost always runs in $O(k.n)$-time where n is the length of the string and k
is the number of ``errors'' allowed in the palindrome. Its worst-case
time-complexity is $O(n^2)$ but this does not occur with real biological
sequences. A more complex algorithm guarantees $O(k.n)$ worst-case time
complexity.


title: Jordan Normal and Rational Normal Form Algorithms

abstract:
  In this paper, we present a determinist Jordan normal form algorithms based
on the Fadeev formula: \[(\lambda \cdot I-A) \cdot B(\lambda)=P(\lambda) \cdot
I\] where $B(\lambda)$ is $(\lambda \cdot I-A)$'s comatrix and $P(\lambda)$ is
$A$'s characteristic polynomial. This rational Jordan normal form algorithm
differs from usual algorithms since it is not based on the Frobenius/Smith
normal form but rather on the idea already remarked in Gantmacher that the
non-zero column vectors of $B(\lambda_0)$ are eigenvectors of $A$ associated to
$\lambda_0$ for any root $\lambda_0$ of the characteristical polynomial. The
complexity of the algorithm is $O(n^4)$ field operations if we know the
factorization of the characteristic polynomial (or $O(n^5 \ln(n))$ operations
for a matrix of integers of fixed size). This algorithm has been implemented
using the Maple and Giac/Xcas computer algebra systems.


title: The Accelerated Euclidean Algorithm

abstract:
  We present a new GCD algorithm of two integers or polynomials. The algorithm
is iterative and its time complexity is still $O(n \\log^2 n ~ log \\log n)$
for $n$-bit inputs.


title: Exploring networks with traceroute-like probes: theory and simulations

abstract:
  Mapping the Internet generally consists in sampling the network from a
limited set of sources by using traceroute-like probes. This methodology, akin
to the merging of different spanning trees to a set of destination, has been
argued to introduce uncontrolled sampling biases that might produce statistical
properties of the sampled graph which sharply differ from the original ones. In
this paper we explore these biases and provide a statistical analysis of their
origin. We derive an analytical approximation for the probability of edge and
vertex detection that exploits the role of the number of sources and targets
and allows us to relate the global topological properties of the underlying
network with the statistical accuracy of the sampled graph. In particular, we
find that the edge and vertex detection probability depends on the betweenness
centrality of each element. This allows us to show that shortest path routed
sampling provides a better characterization of underlying graphs with broad
distributions of connectivity. We complement the analytical discussion with a
throughout numerical investigation of simulated mapping strategies in network
models with different topologies. We show that sampled graphs provide a fair
qualitative characterization of the statistical properties of the original
networks in a fair range of different strategies and exploration parameters.
Moreover, we characterize the level of redundancy and completeness of the
exploration process as a function of the topological properties of the network.
Finally, we study numerically how the fraction of vertices and edges discovered
in the sampled graph depends on the particular deployements of probing sources.
The results might hint the steps toward more efficient mapping strategies.


title: Measured descent: A new embedding method for finite metrics

abstract:
  We devise a new embedding technique, which we call measured descent, based on
decomposing a metric space locally, at varying speeds, according to the density
of some probability measure. This provides a refined and unified framework for
the two primary methods of constructing Frechet embeddings for finite metrics,
due to [Bourgain, 1985] and [Rao, 1999]. We prove that any n-point metric space
(X,d) embeds in Hilbert space with distortion O(sqrt{alpha_X log n}), where
alpha_X is a geometric estimate on the decomposability of X. As an immediate
corollary, we obtain an O(sqrt{(log lambda_X) \log n}) distortion embedding,
where \lambda_X is the doubling constant of X. Since \lambda_X\le n, this
result recovers Bourgain's theorem, but when the metric X is, in a sense,
``low-dimensional,'' improved bounds are achieved.
  Our embeddings are volume-respecting for subsets of arbitrary size. One
consequence is the existence of (k, O(log n)) volume-respecting embeddings for
all 1 \leq k \leq n, which is the best possible, and answers positively a
question posed by U. Feige. Our techniques are also used to answer positively a
question of Y. Rabinovich, showing that any weighted n-point planar graph
embeds in l_\infty^{O(log n)} with O(1) distortion. The O(log n) bound on the
dimension is optimal, and improves upon the previously known bound of O((log
n)^2).


title:
A Fully Sparse Implementation of a Primal-Dual Interior-Point Potential
  Reduction Method for Semidefinite Programming

abstract:
  In this paper, we show a way to exploit sparsity in the problem data in a
primal-dual potential reduction method for solving a class of semidefinite
programs. When the problem data is sparse, the dual variable is also sparse,
but the primal one is not. To avoid working with the dense primal variable, we
apply Fukuda et al.'s theory of partial matrix completion and work with partial
matrices instead. The other place in the algorithm where sparsity should be
exploited is in the computation of the search direction, where the gradient and
the Hessian-matrix product of the primal and dual barrier functions must be
computed in every iteration. By using an idea from automatic differentiation in
backward mode, both the gradient and the Hessian-matrix product can be computed
in time proportional to the time needed to compute the barrier functions of
sparse variables itself. Moreover, the high space complexity that is normally
associated with the use of automatic differentiation in backward mode can be
avoided in this case. In addition, we suggest a technique to efficiently
compute the determinant of the positive definite matrix completion that is
required to compute primal search directions. The method of obtaining one of
the primal search directions that minimizes the number of the evaluations of
the determinant of the positive definite completion is also proposed. We then
implement the algorithm and test it on the problem of finding the maximum cut
of a graph.


title: Toward a Human-Centered Uml for Risk Analysis

abstract:
  Safety is now a major concern in many complex systems such as medical robots.
A way to control the complexity of such systems is to manage risk. The first
and important step of this activity is risk analysis. During risk analysis, two
main studies concerning human factors must be integrated: task analysis and
human error analysis. This multidisciplinary analysis often leads to a work
sharing between several stakeholders who use their own languages and
techniques. This often produces consistency errors and understanding
difficulties between them. Hence, this paper proposes to treat the risk
analysis on the common expression language UML (Unified Modeling Language) and
to handle human factors concepts for task analysis and human error analysis
based on the features of this language. The approach is applied to the
development of a medical robot for teleechography.


title: Successful E-Business Systems - Paypal

abstract:
  PayPal is an account-based system that allows anyone with an email address to
send and receive online payment s. This service is easy to use for customers.
Members can instantaneously send money to anyone. Recipients are informed by
email that they have received a payment. PayPal is also available to people in
38 countries. This paper starts with introduction to the company and its
services. The information about the history and the current company situation
are covered. Later some interesting and different technical issues are
discussed. The Paper ends with analysis of the company and several future
recommendations.


title: Jartege: a Tool for Random Generation of Unit Tests for Java Classes

abstract:
  This report presents Jartege, a tool which allows random generation of unit
tests for Java classes specified in JML. JML (Java Modeling Language) is a
specification language for Java which allows one to write invariants for
classes, and pre- and postconditions for operations. As in the JML-JUnit tool,
we use JML specifications on the one hand to eliminate irrelevant test cases,
and on the other hand as a test oracle. Jartege randomly generates test cases,
which consist of a sequence of constructor and method calls for the classes
under test. The random aspect of the tool can be parameterized by associating
weights to classes and operations, and by controlling the number of instances
which are created for each class under test. The practical use of Jartege is
illustrated by a small case study.


title: Signals for Cellular Automata in dimension 2 or higher

abstract:
  We investigate how increasing the dimension of the array can help to draw
signals on cellular automata.We show the existence of a gap of constructible
signals in any dimension. We exhibit two cellular automata in dimension 2 to
show that increasing the dimension allows to reduce the number of states
required for some constructions.


title: Randomized Initialization of a Wireless Multihop Network

abstract:
  Address autoconfiguration is an important mechanism required to set the IP
address of a node automatically in a wireless network. The address
autoconfiguration, also known as initialization or naming, consists to give a
unique identifier ranging from 1 to $n$ for a set of $n$ indistinguishable
nodes. We consider a wireless network where $n$ nodes (processors) are randomly
thrown in a square $X$, uniformly and independently. We assume that the network
is synchronous and two nodes are able to communicate if they are within
distance at most of $r$ of each other ($r$ is the transmitting/receiving
range). The model of this paper concerns nodes without the collision detection
ability: if two or more neighbors of a processor $u$ transmit concurrently at
the same time, then $u$ would not receive either messages. We suppose also that
nodes know neither the topology of the network nor the number of nodes in the
network. Moreover, they start indistinguishable, anonymous and unnamed. Under
this extremal scenario, we design and analyze a fully distributed protocol to
achieve the initialization task for a wireless multihop network of $n$ nodes
uniformly scattered in a square $X$. We show how the transmitting range of the
deployed stations can affect the typical characteristics such as the degrees
and the diameter of the network. By allowing the nodes to transmit at a range
$r= \sqrt{\frac{(1+\ell) \ln{n} \SIZE}{\pi n}}$ (slightly greater than the one
required to have a connected network), we show how to design a randomized
protocol running in expected time $O(n^{3/2} \log^2{n})$ in order to assign a
unique number ranging from 1 to $n$ to each of the $n$ participating nodes.


title:
A Tutorial on the Expectation-Maximization Algorithm Including
  Maximum-Likelihood Estimation and EM Training of Probabilistic Context-Free
  Grammars

abstract:
  The paper gives a brief review of the expectation-maximization algorithm
(Dempster 1977) in the comprehensible framework of discrete mathematics. In
Section 2, two prominent estimation methods, the relative-frequency estimation
and the maximum-likelihood estimation are presented. Section 3 is dedicated to
the expectation-maximization algorithm and a simpler variant, the generalized
expectation-maximization algorithm. In Section 4, two loaded dice are rolled. A
more interesting example is presented in Section 5: The estimation of
probabilistic context-free grammars.


title: Inside-Outside Estimation Meets Dynamic EM

abstract:
  We briefly review the inside-outside and EM algorithm for probabilistic
context-free grammars. As a result, we formally prove that inside-outside
estimation is a dynamic-programming variant of EM. This is interesting in its
own right, but even more when considered in a theoretical context since the
well-known convergence behavior of inside-outside estimation has been confirmed
by many experiments but apparently has never been formally proved. However,
being a version of EM, inside-outside estimation also inherits the good
convergence behavior of EM. Therefore, the as yet imperfect line of
argumentation can be transformed into a coherent proof.


title: An Analysis of the Skype Peer-to-Peer Internet Telephony Protocol

abstract:
  Skype is a peer-to-peer VoIP client developed by KaZaa in 2003. Skype claims
that it can work almost seamlessly across NATs and firewalls and has better
voice quality than the MSN and Yahoo IM applications. It encrypts calls
end-to-end, and stores user information in a decentralized fashion. Skype also
supports instant messaging and conferencing. This report analyzes key Skype
functions such as login, NAT and firewall traversal, call establishment, media
transfer, codecs, and conferencing under three different network setups.
Analysis is performed by careful study of Skype network traffic.


title: Modeling Complex Higher Order Patterns

abstract:
  The goal of this paper is to show that generalizing the notion of frequent
patterns can be useful in extending association analysis to more complex higher
order patterns. To that end, we describe a general framework for modeling a
complex pattern based on evaluating the interestingness of its sub-patterns. A
key goal of any framework is to allow people to more easily express, explore,
and communicate ideas, and hence, we illustrate how our framework can be used
to describe a variety of commonly used patterns, such as frequent patterns,
frequent closed patterns, indirect association patterns, hub patterns and
authority patterns. To further illustrate the usefulness of the framework, we
also present two new kinds of patterns that derived from the framework: clique
pattern and bi-clique pattern and illustrate their practical use.


title: A Link Clustering Based Approach for Clustering Categorical Data

abstract:
  Categorical data clustering (CDC) and link clustering (LC) have been
considered as separate research and application areas. The main focus of this
paper is to investigate the commonalities between these two problems and the
uses of these commonalities for the creation of new clustering algorithms for
categorical data based on cross-fertilization between the two disjoint research
fields. More precisely, we formally transform the CDC problem into an LC
problem, and apply LC approach for clustering categorical data. Experimental
results on real datasets show that LC based clustering method is competitive
with existing CDC algorithms with respect to clustering accuracy.


title: Towards Reliable Network Wide Broadcast in Mobile Ad Hoc Networks

abstract:
  Network-Wide Broadcast (NWB) is a common operation in Mobile Ad hoc Networks
(MANETs) used by routing protocols to discover routes and in group
communication operations. NWB is commonly performed via flooding, which has
been shown to be expensive in dense MANETs because of its high redundancy.
Several efforts have targeted reducing the redundancy of floods. In this work,
we target another problem that can substantially impact the success of NWBs:
since MAC level broadcasts are unreliable, it is possible for critical
rebroadcasts to be lost, leading to a significant drop in the node coverage.
This is especially true under heavy load and in sparse topologies. We show that
the techniques that target reducing the overhead of flooding, reduce its
inherent redundancy and harm its reliability. In addition, we show that static
approaches are more vulnerable to this problem. We then present a selective
rebroadcast approach to improve the robustness of NWBs. We show that our
approach leads to considerable improvement in NWB coverage relative to a
recently proposed solution to this problem, with a small increase in overhead.
The proposed approaches do not require proactive neighbor discovery and are
therefore resilient to mobility. Finally, the solution can be added to
virtually all NWB approaches to improve their reliability.


title: Finite Domain Bounds Consistency Revisited

abstract:
  A widely adopted approach to solving constraint satisfaction problems
combines systematic tree search with constraint propagation for pruning the
search space. Constraint propagation is performed by propagators implementing a
certain notion of consistency. Bounds consistency is the method of choice for
building propagators for arithmetic constraints and several global constraints
in the finite integer domain. However, there has been some confusion in the
definition of bounds consistency. In this paper we clarify the differences and
similarities among the three commonly used notions of bounds consistency.


title: Zeno machines and hypercomputation

abstract:
  This paper reviews the Church-Turing Thesis (or rather, theses) with
reference to their origin and application and considers some models of
"hypercomputation", concentrating on perhaps the most straight-forward option:
Zeno machines (Turing machines with accelerating clock). The halting problem is
briefly discussed in a general context and the suggestion that it is an
inevitable companion of any reasonable computational model is emphasised. It is
hinted that claims to have "broken the Turing barrier" could be toned down and
that the important and well-founded role of Turing computability in the
mathematical sciences stands unchallenged.


title: Multidimensional data classification with artificial neural networks

abstract:
  Multi-dimensional data classification is an important and challenging problem
in many astro-particle experiments. Neural networks have proved to be versatile
and robust in multi-dimensional data classification. In this article we shall
study the classification of gamma from the hadrons for the MAGIC Experiment.
Two neural networks have been used for the classification task. One is
Multi-Layer Perceptron based on supervised learning and other is
Self-Organising Map (SOM), which is based on unsupervised learning technique.
The results have been shown and the possible ways of combining these networks
have been proposed to yield better and faster classification results.


title:
Human-Level Performance on Word Analogy Questions by Latent Relational
  Analysis

abstract:
  This paper introduces Latent Relational Analysis (LRA), a method for
measuring relational similarity. LRA has potential applications in many areas,
including information extraction, word sense disambiguation, machine
translation, and information retrieval. Relational similarity is correspondence
between relations, in contrast with attributional similarity, which is
correspondence between attributes. When two words have a high degree of
attributional similarity, we call them synonyms. When two pairs of words have a
high degree of relational similarity, we say that their relations are
analogous. For example, the word pair mason/stone is analogous to the pair
carpenter/wood. Past work on semantic similarity measures has mainly been
concerned with attributional similarity. Recently the Vector Space Model (VSM)
of information retrieval has been adapted to the task of measuring relational
similarity, achieving a score of 47% on a collection of 374 college-level
multiple-choice word analogy questions. In the VSM approach, the relation
between a pair of words is characterized by a vector of frequencies of
predefined patterns in a large corpus. LRA extends the VSM approach in three
ways: (1) the patterns are derived automatically from the corpus (they are not
predefined), (2) the Singular Value Decomposition (SVD) is used to smooth the
frequency data (it is also used this way in Latent Semantic Analysis), and (3)
automatically generated synonyms are used to explore reformulations of the word
pairs. LRA achieves 56% on the 374 analogy questions, statistically equivalent
to the average human score of 57%. On the related problem of classifying
noun-modifier relations, LRA achieves similar gains over the VSM, while using a
smaller corpus.


title: Minimum Dilation Stars

abstract:
  The dilation of a Euclidean graph is defined as the ratio of distance in the
graph divided by distance in R^d. In this paper we consider the problem of
positioning the root of a star such that the dilation of the resulting star is
minimal. We present a deterministic O(n log n)-time algorithm for evaluating
the dilation of a given star; a randomized O(n log n) expected-time algorithm
for finding an optimal center in R^d; and for the case d=2, a randomized O(n
2^(alpha(n)) log^2 n) expected-time algorithm for finding an optimal center
among the input points.


title: Removing Propagation Redundant Constraints in Redundant Modeling

abstract:
  A widely adopted approach to solving constraint satisfaction problems
combines systematic tree search with various degrees of constraint propagation
for pruning the search space. One common technique to improve the execution
efficiency is to add redundant constraints, which are constraints logically
implied by others in the problem model. However, some redundant constraints are
propagation redundant and hence do not contribute additional propagation
information to the constraint solver. Redundant constraints arise naturally in
the process of redundant modeling where two models of the same problem are
connected and combined through channeling constraints. In this paper, we give
general theorems for proving propagation redundancy of one constraint with
respect to channeling constraints and constraints in the other model. We
illustrate, on problems from CSPlib (http://www.csplib.org/), how detecting and
removing propagation redundant constraints in redundant modeling can
significantly speed up constraint solving.


title: Correlated dynamics in human printing behavior

abstract:
  Arrival times of requests to print in a student laboratory were analyzed.
Inter-arrival times between subsequent requests follow a universal scaling law
relating time intervals and the size of the request, indicating a scale
invariant dynamics with respect to the size. The cumulative distribution of
file sizes is well-described by a modified power law often seen in
non-equilibrium critical systems. For each user, waiting times between their
individual requests show long range dependence and are broadly distributed from
seconds to weeks. All results are incompatible with Poisson models, and may
provide evidence of critical dynamics associated with voluntary thought
processes in the brain.


title: A feasible algorithm for typing in Elementary Affine Logic

abstract:
  We give a new type inference algorithm for typing lambda-terms in Elementary
Affine Logic (EAL), which is motivated by applications to complexity and
optimal reduction. Following previous references on this topic, the variant of
EAL type system we consider (denoted EAL*) is a variant without sharing and
without polymorphism. Our algorithm improves over the ones already known in
that it offers a better complexity bound: if a simple type derivation for the
term t is given our algorithm performs EAL* type inference in polynomial time.


title:
The modular technology of development of the CAD expansions: profiles of
  outside networks of water supply and water drain

abstract:
  The modular technology of development of the problem-oriented CAD expansions
is applied to a task of designing of profiles of outside networks of water
supply and water drain with realization in program system TechnoCAD GlassX. The
unity of structure of this profiles is revealed, the system model of the
drawings of profiles of networks is developed including the structured
parametric representation (properties of objects and their interdependence,
general settings and default settings) and operations with it, which
efficiently automate designing


title:
The modular technology of development of the CAD expansions: protection
  of the buildings from the lightning

abstract:
  The modular technology of development of the problem-oriented CAD expansions
is applied to a task of designing of protection of the buildings from the
lightning with realization in program system TechnoCAD GlassX. The system model
of the drawings of lightning protection is developed including the structured
parametric representation (properties of objects and their interdependence,
general settings and default settings) and operations with it, which
efficiently automate designing


title:
The Features of the Complex CAD system of Reconstruction of the
  Industrial Plants

abstract:
  The features of designing of reconstruction of the acting plant by its design
department are considered: the results of work are drawings corresponding with
the national standards; large number of the small projects for different acting
objects; variety of the types of the drawings in one project; large paper
archive. The models and methods of developing of the complex CAD system with
friend uniform environment of designing, with setting a profile of operations,
with usage of the general parts of the project, with a series of
problem-oriented subsystems are described on an example of a CAD system
TechnoCAD GlassX


title:
The methods of support of the requirements of the Russian standards at
  development of a CAD of industrial objects

abstract:
  The methods of support of the requirements of the Russian standards in a CAD
of industrial objects are explained, which were implemented in the CAD system
TechnoCAD GlassX with an own graphics core and own structures of data storage.
It is rotined, that the binding of storage structures and program code of a CAD
to the requirements of standards enable not only to fulfil these requirements
in project documentation, but also to increase a degree of compactness of
storage of drawings both on the disk and in the RAM


title:
The modelling of the build constructions in a CAD of the renovation of
  the enterprises by means of units in the drawings

abstract:
  The parametric model of build constructions and features of design operations
are described for making drawings, which are the common component of the
different parts of the projects of renovation of enterprises. The key moment of
the deep design automation is the using of so-called units in the drawings,
which are joining a visible graphic part and invisible parameters. The model
has passed check during designing of several hundreds of drawings


title:
The informatization of design works at industry firm during its
  renovation

abstract:
  The characteristic of design works on firm at its renovation and of the
common directions of their informatization is given. The implantation of a CAD
is selected as the key direction, and the requirements to a complex CAD-system
are stated. The methods of such a CAD-system development are featured, and the
connectedness of this development with the process of integration of
information space of design department of the firm is characterized. The
experience of development and implantation of a complex CAD of renovation of
firms TechnoCAD GlassX lies in a basis of this reviewing


title: Deployment of a Grid-based Medical Imaging Application

abstract:
  The MammoGrid project has deployed its Service-Oriented Architecture
(SOA)-based Grid application in a real environment comprising actual
participating hospitals. The resultant setup is currently being exploited to
conduct rigorous in-house tests in the first phase before handing over the
setup to the actual clinicians to get their feedback. This paper elaborates the
deployment details and the experiences acquired during this phase of the
project. Finally the strategy regarding migration to an upcoming middleware
from EGEE project will be described. This paper concludes by highlighting some
of the potential areas of future work.


title: Reverse Engineering Ontology to Conceptual Data Models

abstract:
  Ontologies facilitate the integration of heterogeneous data sources by
resolving semantic heterogeneity between them. This research aims to study the
possibility of generating a domain conceptual model from a given ontology with
the vision to grow this generated conceptual data model into a global
conceptual model integrating a number of existing data and information sources.
Based on ontologically derived semantics of the BWW model, rules are identified
that map elements of the ontology language (DAML+OIL) to domain conceptual
model elements. This mapping is demonstrated using TAMBIS ontology. A
significant corollary of this study is that it is possible to generate a domain
conceptual model from a given ontology subject to validation that needs to be
performed by the domain specialist before evolving this model into a global
conceptual model.


title:
A Statistical Framework for Efficient Monitoring of End-to-End Network
  Properties

abstract:
  Network service providers and customers are often concerned with aggregate
performance measures that span multiple network paths. Unfortunately, forming
such network-wide measures can be difficult, due to the issues of scale
involved. In particular, the number of paths grows too rapidly with the number
of endpoints to make exhaustive measurement practical. As a result, there is
interest in the feasibility of methods that dramatically reduce the number of
paths measured in such situations while maintaining acceptable accuracy.
  In previous work we proposed a statistical framework to efficiently address
this problem, in the context of additive metrics such as delay and loss rate,
for which the per-path metric is a sum of (possibly transformed) per-link
measures. The key to our method lies in the observation and exploitation of
significant redundancy in network paths (sharing of common links).
  In this paper we make three contributions: (1) we generalize the framework to
make it more immediately applicable to network measurements encountered in
practice; (2) we demonstrate that the observed path redundancy upon which our
method is based is robust to variation in key network conditions and
characteristics, including link failures; and (3) we show how the framework may
be applied to address three practical problems of interest to network providers
and customers, using data from an operating network. In particular, we show how
appropriate selection of small sets of path measurements can be used to
accurately estimate network-wide averages of path delays, to reliably detect
network anomalies, and to effectively make a choice between alternative
sub-networks, as a customer choosing between two providers or two ingress
points into a provider network.


title:
Tycoon: an Implementation of a Distributed, Market-based Resource
  Allocation System

abstract:
  Distributed clusters like the Grid and PlanetLab enable the same statistical
multiplexing efficiency gains for computing as the Internet provides for
networking. One major challenge is allocating resources in an economically
efficient and low-latency way. A common solution is proportional share, where
users each get resources in proportion to their pre-defined weight. However,
this does not allow users to differentiate the value of their jobs. This leads
to economic inefficiency. In contrast, systems that require reservations impose
a high latency (typically minutes to hours) to acquire resources.
  We present Tycoon, a market based distributed resource allocation system
based on proportional share. The key advantages of Tycoon are that it allows
users to differentiate the value of their jobs, its resource acquisition
latency is limited only by communication delays, and it imposes no manual
bidding overhead on users. We present experimental results using a prototype
implementation of our design.


title: Security in Carrier Class Server Applications for All-IP Networks

abstract:
  A revolution is taking place in telecommunication networks. New services are
appearing on platforms such as third generation cellular phones (3G) and
broadband Internet access. This motivates the transition from mostly switched
to all-IP networks. The replacement of the traditional shallow and well-defined
interface to telephony networks brings accrued flexibility, but also makes the
network accordingly difficult to properly secure. This paper surveys the
implications of this transition on security issues in telecom applications. It
does not give an exhaustive list of security tools or security protocols. Its
goal is rather to initiate the reader to the security issues brought to carrier
class servers by this revolution.


title: Data-stationary Architecture to Execute Quantum Algorithms Classically

abstract:
  This paper presents a data stationary architecture in which each word has an
attached address field. Address fields massively update in parallel to record
data interchanges. Words do not move until memory is read for post processing.
A sea of such cells can test large-scale quantum algorithms, although other
programming is possible.


title: An Efficient and Flexible Engine for Computing Fixed Points

abstract:
  An efficient and flexible engine for computing fixed points is critical for
many practical applications. In this paper, we firstly present a goal-directed
fixed point computation strategy in the logic programming paradigm. The
strategy adopts a tabled resolution (or memorized resolution) to mimic the
efficient semi-naive bottom-up computation. Its main idea is to dynamically
identify and record those clauses that will lead to recursive variant calls,
and then repetitively apply those alternatives incrementally until the fixed
point is reached. Secondly, there are many situations in which a fixed point
contains a large number or even infinite number of solutions. In these cases, a
fixed point computation engine may not be efficient enough or feasible at all.
We present a mode-declaration scheme which provides the capabilities to reduce
a fixed point from a big solution set to a preferred small one, or from an
infeasible infinite set to a finite one. The mode declaration scheme can be
characterized as a meta-level operation over the original fixed point. We show
the correctness of the mode declaration scheme. Thirdly, the mode-declaration
scheme provides a new declarative method for dynamic programming, which is
typically used for solving optimization problems. There is no need to define
the value of an optimal solution recursively, instead, defining a general
solution suffices. The optimal value as well as its corresponding concrete
solution can be derived implicitly and automatically using a mode-directed
fixed point computation engine. Finally, this fixed point computation engine
has been successfully implemented in a commercial Prolog system. Experimental
results are shown to indicate that the mode declaration improves both time and
space performances in solving dynamic programming problems.


title: The approximability of three-valued MAX CSP

abstract:
  In the maximum constraint satisfaction problem (Max CSP), one is given a
finite collection of (possibly weighted) constraints on overlapping sets of
variables, and the goal is to assign values from a given domain to the
variables so as to maximize the number (or the total weight, for the weighted
case) of satisfied constraints. This problem is NP-hard in general, and,
therefore, it is natural to study how restricting the allowed types of
constraints affects the approximability of the problem. It is known that every
Boolean (that is, two-valued) Max CSP problem with a finite set of allowed
constraint types is either solvable exactly in polynomial time or else
APX-complete (and hence can have no polynomial time approximation scheme unless
P=NP. It has been an open problem for several years whether this result can be
extended to non-Boolean Max CSP, which is much more difficult to analyze than
the Boolean case. In this paper, we make the first step in this direction by
establishing this result for Max CSP over a three-element domain. Moreover, we
present a simple description of all polynomial-time solvable cases of our
problem. This description uses the well-known algebraic combinatorial property
of supermodularity. We also show that every hard three-valued Max CSP problem
contains, in a certain specified sense, one of the two basic hard Max CSP
problems which are the Maximum k-colourable subgraph problems for k=2,3.


title:
Widening Operators for Weakly-Relational Numeric Abstractions (Extended
  Abstract)

abstract:
  We discuss the divergence problems recently identified in some extrapolation
operators for weakly-relational numeric domains. We identify the cause of the
divergences and point out that resorting to more concrete, syntactic domains
can be avoided by researching suitable algorithms for the elimination of
redundant constraints in the chosen representation.


title: TulaFale: A Security Tool for Web Services

abstract:
  Web services security specifications are typically expressed as a mixture of
XML schemas, example messages, and narrative explanations. We propose a new
specification language for writing complementary machine-checkable descriptions
of SOAP-based security protocols and their properties. Our TulaFale language is
based on the pi calculus (for writing collections of SOAP processors running in
parallel), plus XML syntax (to express SOAP messaging), logical predicates (to
construct and filter SOAP messages), and correspondence assertions (to specify
authentication goals of protocols). Our implementation compiles TulaFale into
the applied pi calculus, and then runs Blanchet's resolution-based protocol
verifier. Hence, we can automatically verify authentication properties of SOAP
protocols.


title: Validating a Web Service Security Abstraction by Typing

abstract:
  An XML web service is, to a first approximation, an RPC service in which
requests and responses are encoded in XML as SOAP envelopes, and transported
over HTTP. We consider the problem of authenticating requests and responses at
the SOAP-level, rather than relying on transport-level security. We propose a
security abstraction, inspired by earlier work on secure RPC, in which the
methods exported by a web service are annotated with one of three security
levels: none, authenticated, or both authenticated and encrypted. We model our
abstraction as an object calculus with primitives for defining and calling web
services. We describe the semantics of our object calculus by translating to a
lower-level language with primitives for message passing and cryptography. To
validate our semantics, we embed correspondence assertions that specify the
correct authentication of requests and responses. By appeal to the type theory
for cryptographic protocols of Gordon and Jeffrey's Cryptyc, we verify the
correspondence assertions simply by typing. Finally, we describe an
implementation of our semantics via custom SOAP headers.


title: Quasiconvex Programming

abstract:
  We define quasiconvex programming, a form of generalized linear programming
in which one seeks the point minimizing the pointwise maximum of a collection
of quasiconvex functions. We survey algorithms for solving quasiconvex programs
either numerically or via generalizations of the dual simplex method from
linear programming, and describe varied applications of this geometric
optimization technique in meshing, scientific computation, information
visualization, automated algorithm analysis, and robust statistics.


title: A Social Network for Societal-Scale Decision-Making Systems

abstract:
  In societal-scale decision-making systems the collective is faced with the
problem of ensuring that the derived group decision is in accord with the
collective's intention. In modern systems, political institutions have
instatiated representative forms of decision-making to ensure that every
individual in the society has a participatory voice in the decision-making
behavior of the whole--even if only indirectly through representation. An
agent-based simulation demonstrates that in modern representative systems, as
the ratio of representatives increases, there exists an exponential decrease in
the ability for the group to behave in accord with the desires of the whole. To
remedy this issue, this paper provides a novel representative power structure
for decision-making that utilizes a social network and power distribution
algorithm to maintain the collective's perspective over varying degrees of
participation and/or ratios of representation. This work shows promise for the
future development of policy-making systems that are supported by the computer
and network infrastructure of our society.


title: On computing fixed points for generalized sandpiles

abstract:
  We prove fixed points results for sandpiles starting with arbitrary initial
conditions. We give an effective algorithm for computing such fixed points, and
we refine it in the particular case of SPM.


title: Neural Networks in Mobile Robot Motion

abstract:
  This paper deals with a path planning and intelligent control of an
autonomous robot which should move safely in partially structured environment.
This environment may involve any number of obstacles of arbitrary shape and
size; some of them are allowed to move. We describe our approach to solving the
motion-planning problem in mobile robot control using neural networks-based
technique. Our method of the construction of a collision-free path for moving
robot among obstacles is based on two neural networks. The first neural network
is used to determine the "free" space using ultrasound range finder data. The
second neural network "finds" a safe direction for the next robot section of
the path in the workspace while avoiding the nearest obstacles. Simulation
examples of generated path with proposed techniques will be presented.


title: Gyroscopically Stabilized Robot: Balance and Tracking

abstract:
  The single wheel, gyroscopically stabilized robot - Gyrover, is a dynamically
stable but statically unstable, underactuated system. In this paper, based on
the dynamic model of the robot, we investigate two classes of nonholonomic
constraints associated with the system. Then, based on the backstepping
technology, we propose a control law for balance control of Gyrover. Next,
through transferring the systems states from Cartesian coordinate to polar
coordinate, control laws for point-to-point control and line tracking in
Cartesian space are provided.


title:
Dynamic replanning in uncertain environments for a sewer inspection
  robot

abstract:
  The sewer inspection robot MAKRO is an autonomous multi-segment robot with
worm-like shape driven by wheels. It is currently under development in the
project MAKRO-PLUS. The robot has to navigate autonomously within sewer
systems. Its first tasks will be to take water probes, analyze it onboard, and
measure positions of manholes and pipes to detect polluted-loaded sewage and to
improve current maps of sewer systems. One of the challenging problems is the
controller software, which should enable the robot to navigate in the sewer
system and perform the inspection tasks autonomously, not inflicting any
self-damage. This paper focuses on the route planning and replanning aspect of
the robot. The robots software has four different levels, of which the planning
system is the highest level, and the remaining three are controller levels each
with a different degree of abstraction. The planner coordinates the sequence of
actions that are to be successively executed by the robot.


title: WebotsTM: Professional Mobile Robot Simulation

abstract:
  Cyberbotics Ltd. develops WebotsTM, a mobile robotics simulation software
that provides you with a rapid prototyping environment for modelling,
programming and simulating mobile robots. The provided robot libraries enable
you to transfer your control programs to several commercially available real
mobile robots. WebotsTM lets you define and modify a complete mobile robotics
setup, even several different robots sharing the same environment. For each
object, you can define a number of properties, such as shape, color, texture,
mass, friction, etc. You can equip each robot with a large number of available
sensors and actuators. You can program these robots using your favorite
development environment, simulate them and optionally transfer the resulting
programs onto your real robots. WebotsTM has been developed in collaboration
with the Swiss Federal Institute of Technology in Lausanne, thoroughly tested,
well documented and continuously maintained for over 7 years. It is now the
main commercial product available from Cyberbotics Ltd.


title: Dynamic simulation of task constrained of a rigid-flexible manipulator

abstract:
  A rigid-flexible manipulator may be assigned tasks in a moving environment
where the winds or vibrations affect the position and/or orientation of surface
of operation. Consequently, losses of the contact and perhaps degradation of
the performance may occur as references are changed. When the environment is
moving, knowledge of the angle α between the contact surface and the
horizontal is required at every instant. In this paper, different profiles for
the time varying angle α are proposed to investigate the effect of this
change into the contact force and the joint torques of a rigid-flexible
manipulator. The coefficients of the equation of the proposed rotating surface
are changing with time to determine the new X and Y coordinates of the moving
surface as the surface rotates.


title:
Assembly and Disassembly Planning by using Fuzzy Logic & Genetic
  Algorithms

abstract:
  The authors propose the implementation of hybrid Fuzzy Logic-Genetic
Algorithm (FL-GA) methodology to plan the automatic assembly and disassembly
sequence of products. The GA-Fuzzy Logic approach is implemented onto two
levels. The first level of hybridization consists of the development of a Fuzzy
controller for the parameters of an assembly or disassembly planner based on
GAs. This controller acts on mutation probability and crossover rate in order
to adapt their values dynamically while the algorithm runs. The second level
consists of the identification of theoptimal assembly or disassembly sequence
by a Fuzzy function, in order to obtain a closer control of the technological
knowledge of the assembly/disassembly process. Two case studies were analyzed
in order to test the efficiency of the Fuzzy-GA methodologies.


title: Robotic Applications in Cardiac Surgery

abstract:
  Traditionally, cardiac surgery has been performed through a median
sternotomy, which allows the surgeon generous access to the heart and
surrounding great vessels. As a paradigm shift in the size and location of
incisions occurs in cardiac surgery, new methods have been developed to allow
the surgeon the same amount of dexterity and accessibility to the heart in
confined spaces and in a less invasive manner. Initially, long instruments
without pivot points were used, however, more recent robotic telemanipulation
systems have been applied that allow for improved dexterity, enabling the
surgeon to perform cardiac surgery from a distance not previously possible. In
this rapidly evolving field, we review the recent history and clinical results
of using robotics in cardiac surgery.