**2.28 Health Canada, July (2009)**

http://www.hc-sc.gc.ca/ewh-semt/radiation/cons/stations/index-eng.php http://www.hc-sc.gc.ca/ewh-semt/radiation/cons/radiofreq/index-eng.php http://www.hc-sc.gc.ca/ewh-semt/pubs/radiation/radio\_guide-lignes\_direct-eng.php

Health Canada is the Federal department responsible for helping Canadians maintain and improve their health, while respecting individual choices and circumstances. It publishes different documents and fact sheets (see for example website addresses given above). According to these the consensus of the scientific community is that RF energy from cell phone towers is too low to cause adverse health effects in humans. In fact, worst-case RF exposure levels emitted from cell phone towers are typically thousands of times below those specified by science-based exposure standards. The RF energy from cell phones also poses no confirmed health risk but it is acknowledged that cell phone use is not entirely risk-free due to distraction, possible interference with some (medical) devices or other sensitive electronic equipment.

The Health Protection Agency (formerly National Radiological Protection Board) issues different reports and information booklets on different aspects of (amongst others) mobile phone effects. According to their 2010 statement "there are thousands of published scientific papers covering research about the effects of various types of radio waves on cells, tissues, animals and people. The scientific consensus is that, apart from the increased risk of a road accident due to mobile phone use when driving, there is no clear evidence of adverse health

The ministry states in a brochure that there is no scientific evidence that cellular phones are hazardous to man. The brochure yet recommends a reasonable use of a mobile phone and

**2.27 Australian Radiation Protection and Nuclear Safety Agency (ARPANSA, 2009)**

In an update of its fact sheet on mobile telephony and health ARPANSA says that "*there is essentially no evidence that microwave exposure from mobile telephones causes cancer, and no clear evidence that such exposure accelerates the growth of an already-existing cancer. More research on this issue has been recommended. "Users concerned about the possibility of health effects can minimize their exposure to the microwave emissions by limiting the duration of mobile telephone calls, using a mobile telephone which does not have the antenna in the handset or using a 'hands-free' attachment. "There is no clear evidence in the existing scientific literature that the use of mobile telephones poses a long-term*

*public health hazard (although the possibility of a small risk cannot be ruled out).*"

http://www.hc-sc.gc.ca/ewh-semt/radiation/cons/stations/index-eng.php http://www.hc-sc.gc.ca/ewh-semt/radiation/cons/radiofreq/index-eng.php

http://www.hc-sc.gc.ca/ewh-semt/pubs/radiation/radio\_guide-lignes\_direct-eng.php

Health Canada is the Federal department responsible for helping Canadians maintain and improve their health, while respecting individual choices and circumstances. It publishes different documents and fact sheets (see for example website addresses given above). According to these the consensus of the scientific community is that RF energy from cell phone towers is too low to cause adverse health effects in humans. In fact, worst-case RF exposure levels emitted from cell phone towers are typically thousands of times below those specified by science-based exposure standards. The RF energy from cell phones also poses no confirmed health risk but it is acknowledged that cell phone use is not entirely risk-free due to distraction, possible interference with some (medical) devices or other sensitive

**2.25 Reports from the Health Protection Agency (HPA)**

effects from the use of mobile phones or from phone masts".

**2.26 The Austrian ministry of health (2009)**

www.arpansa.gov.au/pubs/eme/fact1.pdf

**2.28 Health Canada, July (2009)**

electronic equipment.

http://www.hpa.org.uk/

limited use by children.

www.arpansa.gov.au/


**7. Conclusions and future research**

The goal of this research was to evaluate the feasibility of adopting HCI usability techniques in OSS projects. We adapted the focus groups technique for adoption. Through adaptation, we were able to account for some OSS development characteristics that pose an obstacle to the application of the technique as per HCI recommendations (for example, OSS developers and users are geographically distributed). In particular, we adapted the focus groups usability technique for application in the ERMaster OSS project.

It is not easy to recruit volunteer users to participate in OSS usability projects. As already mentioned, users often do not have much time, and it is hard to get them to take part without an incentive. With the focus groups technique, although we did not get much collaboration from users or even the principal developers, we did manage to apply the technique because it requires only a small number of participants to get a reliable result [14, 15, 34–36]. Author opinions differ as to the number of users to be taken into account for the focus groups technique to be successful [14, 15, 34–36]. Most of these authors agree that a focus group should include from six to nine users if it is to work. Fewer than six participants would not generate enough ideas for discussion. In this research, however, any users that are willing to collaborate are allowed to, that is, there is no limit on the number of users because this would go against the working philosophy of the OSS community where anyone who wants to is welcome to participate. In sum, our proposed adaptation does not place any constraints on the number of technique participants. This adaptation is a response to the OSS community working philosophy rather than to an adverse condition posing an obstacle to technique application.

The focus groups technique is useful for gathering opinions and suggestions from participant users for the product concept development activity and its results are descriptive. After analysing and applying the focus groups usability technique in requirements engineering activities in OSS developments, we found that there are adverse conditions that are an obstacle to its application like, for example, the shortage of OSS users interested in applying the technique, community geographical and temporal distribution and OSS community motivation.

We believe that, in order to improve the integration of usability techniques in OSS projects, the OSS community has to start attaching importance to and raising awareness about the repercussions that the issues addressed by the HCI field have on software development. Additionally, as HCI techniques need to be adapted to overcome the adverse conditions for adoption in OSS development projects, the OSS community also has to broaden its view of software development in order to consider usability and not focus exclusively on feature development. In the future, we aim to conduct further case studies to adapt and apply other usability techniques in OSS projects. We will analyse other web artefacts that can be adapted to improve communication in OSS communities (e.g., social networks) and gradually raise the awareness of OSS developers about the benefits of applying HCI usability techniques.


**5. Conclusion**

**Figure 7.** Displacement response of the structural system with the MR mount.

98 Advances in Vibration Engineering and Structural Dynamics

**Figure 8.** Acceleration response of the structural system with the MR mount.

In order to implement the LQG controller, an experimental setup is established as shown in Figure 6. The mass supported by the MR mount is excited by the electromagnetic exciter, and the excitation force and frequency are regulated by the exciter controller. Accelerometers are A new type of the mixed-mode MR mount was proposed and applied to vibration control of a flexible beam structure system. On the basis of non-dimensional Bingham number, an appro‐ priate size of the MR mount was designed and manufactured. After experimentally evaluat‐ ing the field-dependent damping force of the MR mount, a structural system consisting of a flexible beam and vibrating rigid mass was established. The governing equation of motion of the system was formulated and a linear quadratic Gaussian (LQG) controller was designed to attenuate the vibration of the structural system. It has been demonstrated through experimen‐ tal realization that the imposed vibrations of the structural system such as acceleration and displacement are favorably reduced by activating the proposed MR mount associated with the optimal controller. The control results presented in this study are quite self-explanatory justi‐ fying that the proposed semi-active MR mount can be effectively utilized to the vibration con‐ trol of various structural systems such as flexible robot arm and satellite appendages.