**1. Introduction**

Smart, sustainable, and knowledge-based urban development (KBUD) is the catchphrase of our time, as the whole world struggles with climate, pandemic, and financial emergencies [1,2]. Particularly, in the case of emerging economies, this has had a severe impact for Brazil, among others [3–5]. In this case report, we placed an emerging innovation capital of Brazil, namely Florianópolis, under the microscope to generate insights for determining effective and efficient strategies to increase sustainability and innovation capabilities of cities to achieve long-term desired urban outcomes in the age of climate, pandemic, and financial catastrophes.

Florianópolis is the capital of the Brazilian southern state of Santa Catarina. Mostly located in the Santa Catarina Island, Florianópolis has a population of approximately half a million inhabitants [6], a per capita GDP of R 40,162 (around USD 7452) [7] and a Human Development Index of 0.847, the third best city in Brazil [8]. Thanks to its coastal and isolated nature and subtropical climate, the city is a popular tourist destination for both Brazilians and South American travelers.

Around the 1980s, the city started looking for alternatives to tackle its evident economic growth limitations. As its territory is mostly insular, Florianópolis could only offer employment in the public, retail, fishing, and tourism sectors, as industrial developments were, and still are, strictly forbidden by environmental regulations. Through federal, state, and municipal incentives, and taking advantage of the presence of high-quality universities, mostly focused on engineering, the technology sector was established as a viable form of development that coupled with environmental concerns while bringing high added value and generating employment and income. In these circumstances, in the 1980s, two important institutions were founded in Florianópolis to foster an ecosystem of technology and innovation, i.e., Centers of Reference in Innovative Technologies Foundation (CERTI) and the Technology Association of Santa Catarina (ACATE).

During the 1990s, a significant number of software companies, a technological park, ParqTec Alfa, and two incubators, CELTA and MIDI, were established in Florianópolis. A few years later, in 2006, an innovation center, named Sapiens Park, was established in the city as a joint initiative from the state government and the CERTI Foundation. As a result of the joint efforts conducted by the state and city government, universities and entrepreneurs, the city successfully established itself as an innovation center in the late 2000s, thus, recognized both in Brazil and abroad. Currently, the technology sector in Florianópolis generates over R 4.3 billion (around USD 798 million) in revenue per year and employs more than 17,000 people [9]. According to the 2020 edition of the Connected Smart Cities Ranking, which maps the cities with the greatest development potential in Brazil, Florianópolis was ranked as the second most intelligent and connected city in the country [10]. The city won third place in the economy category, in addition to fourth place in the technology and innovation category, fifth place in mobility and accessibility, seventh place in entrepreneurship and health, and 10th in security in the same ranking [10]. Florianópolis was also ranked as the second best entrepreneurial ecosystem amongst the major cities in Brazil, according to the Entrepreneur Cities Index [11].

Local tax exemptions and incentives and public policy programs set up by the Municipal Law of Innovation, issued in 2012, have played, and still play, an important role in Florianópolis economic transition to technology and innovation. A Municipal Innovation Council (CMI) was established as the main managing body of innovation policy and, since 2007, the city mobilized the local innovation ecosystem through the so-called "Innovation Promotion Arrangements (API)", aimed to fund selected projects with both public and private resources, including the Municipal Innovation Fund and the Tax Incentive Program for Innovation. Correspondingly, the local government mapped out a "Route of Innovation", in order to identify and interconnect the city's innovation and technology strategic points as a means to present and promote Florianópolis' innovation ecosystem through a roadmap, extending from the city center to the North of the island. The "Route of Innovation" also aims to connect government, academia, companies, and the community in general, to leverage the entrepreneurial and innovative potential of all actors involved [12].

Recently, two major events have marked Florianópolis, also known as Floripa, development towards a more sustainable city, the new operation of the Florianópolis International Airport and the reopening of the Hercílio Luz Bridge. The Floripa Airport has been managed by a company that also manages Zurich Airport, assuming the city's international airport operations for a period of 30 years and investing in the construction of a new passenger's terminal, inaugurated in 2019. Additionally, the iconic Hercílio Luz Bridge, the longest suspension bridge in Brazil and the first link from Santa Catarina island to the mainland, was restored and reopened to the public on 30 December 2019 after 28 years of closure.

In this context, a research project named the "Smart Floripa Project" was developed between 2018 and 2019 in order to determine whether or not, and to what extent, the KBUD framework could contribute to transform Florianópolis into a smart city of innovation by 2030. The Smart Floripa Project was promoted as a joint effort of a set of institutions, including the Federal University of Santa Catarina, the Institute of Advanced Studies of the University of São Paulo, the Queensland University of Technology, Fecomércio SC, Senac SC, the Brazilian Association of Software Companies, the Lixo Zero Brasil Institute, the Government of the State of Santa Catarina, and the Municipality of Florianópolis.

The investigation was developed as a qualitative study, with surveys and in-depth interviews with multiple stakeholders engaged in the city's innovation ecosystem. The results, as indicated below, revealed that Florianópolis' potential for innovation stemmed from its natural, human, social, and intellectual characteristics, and the main obstacles opposing the city's ambition to become a smart city of innovation stemmed from significant political and governance gaps [13–15].

These political and governance gaps consist, first, of an alarming lack of experience in evidence-based public policymaking amongst all the city's stakeholders. As a result, decision-making processes do not rely on concrete data or scientific evidence, which, bottom line, leads to poor quality and unsustainable public policies, as both public and private managers lack the knowledge and consistent data on sustainable urban development opportunities and challenges [16]. In other words, the city needs to establish a support model for public policy decision making, which could be provided by the KBUD framework.

Finally, Florianópolis needs to balance its innovative ambition with sustainable urban development standards, especially in regards to social equity and environmental protection. In this case, it must be explored whether or not KBUD can articulate these elements and what the existing benchmarks and references are in the matter. In this setting, this paper aims to collect inputs and reflections for the drafting of evidence-based public policies in favor of Florianópolis' ambition to become a smart city of innovation within sustainable development standards, that is, balancing economic prosperity, social equity, and environmental protection through technology and innovation.


**3. MBBR case study**

This chapter provides a case study where the novel CFIC biofilm process has been studied for municipal wastewater treatment, including for organic, ammonia, and total nitrogen removal. The CFIC process operates in two modes, a normal operation where high carrier filling is applied and a washing mode for extra sludge removal (**Figure 6**). Detailed process concept description can be referred to [34], and more information is given in the following presentation of a three-stage CFIC pilot for municipal organic and nitrogen removal. The first full-scale three-stage CFIC process has also been accomplished for a 30,000 m3 /d municipal wastewater treatment in Guiyang, China, in 2017.

**11**

**Table 2.**

*Feed wastewater characteristics in the two test periods.*

**Figure 7.**

*Pilot system PID layout.*

*Biofilm in Moving Bed Biofilm Process for Wastewater Treatment*

A pilot CFIC plant with a maximum feeding capacity of 6 m3

(**Figure 7**). The three biological stages are 8.7, 8.3, and 8.3 m3

cycle was performed in the other two aerobic stages.

structed for municipal wastewater treatment study at NRA, Norway. The pilot plant constitutes of a pre-denitrification (R1), two aerobic CFIC stages (R2 and R3), and a sludge settler for sludge removal and supernatant return to biological stages

volume. Biocarriers of BWT15® and BWTX® (**Figure 3**) were filled in the first and the other two stages separately. During normal CFIC operation, a filling ratio of 62, 86, and 83%, respectively, is applied. The filling degree of the pre-denitrification was kept constant at 62% while reduced to 71 and 69% when intermittent washing

The pilot was fed with municipal wastewater directly pumped from the full-scale primary clarifier onsite (**Figure 7**), and the wastewater characteristics are given in **Table 2**. The wastewater temperature was around 15°C in the whole year. The waste-

To facilitate biofilm growth on carriers, washing mode was applied at the beginning of the test until stable biofilm growth was observed. The pre-denitrification stage was washed daily, and the two aerobic stages were washed together in every 1 or 2 days after the first reactor washing cycle finished. The washing cycle for each stage

**Average feed condition Period 1 (15.05–29.06) Period 2 (24.10–01.12)**

TCOD (mg/L) 392 214 TSS (mg/L) 264 123 NH4-N (mg/L) 20.4 14.5 TN (mg/L) 45 29 pH 7.2 7.0

/h to the system with a recycle ratio of 1–1.5 during the study.

/h has been con-

, respectively, in

*DOI: http://dx.doi.org/10.5772/intechopen.88520*

**3.1 Pilot layout**

water was fed at 3–6 m3

**Figure 6.** *The CFIC® during (a) normal operation and during (b) the cleaning cycle.*


**4.6 Management and treatment of MH during anesthesia for liver transplantation**

#### **4.6.1 Intraoperatively**

Protocols for MH treatment prioritize four mainstays: immediate discontinuation of trigger agents, administration of antidote (sodium dantrolene), life support measures and prevention of complications124-125.

In the acute phase of MH the following steps are recommended:

General dosing regimens recommend an initial bolus of 2.5 mg.kg-1, which can be repeated every 5 minutes until normalization of the hypermetabolic state and the disappearance of all MH symptoms. After this initial control, a continuous intravenous dantrolene infusion at 10 mg.kg-1.day-1 should be given for at least 24 h after initial successful therapy76.

Although this is the classical regimen, it may be excessive and deleterious in liver transplantation patients. In this scenario, although the diseased liver is removed and a new liver graft is transplanted, the transplanted liver unavoidably sustains warm, cold, and reperfusion injuries during graft procurement and transplantation129. Dantrolene sodium is considered hepatotoxic and the hepatic effects of dantrolene on such liver allografts are unknown. As a result, it seems prudent to use the lowest effective dose for the shortest time possible.

There are two published case reports of MH in liver transplantation, with identical clinical presentation and successful treatment with lower than usual dantrolene doses56,96. One of the reports used a 1 mg.kg-1 dose intraoperatively, followed by 1 mg.kg-1 every eight hours for 36 hours; the authors observed signs of hepatic

Protocols for MH treatment prioritize four mainstays: immediate discontinuation of trigger agents, administration of antidote (sodium dantrolene), life support measures and

1. **Immediate discontinuation of triggering agents:** some MH crisis may be attenuated or aborted with discontinuation of triggering agents. When MH or MMR is identified soon after induction, postponement of the surgery is commonly recommended119. In liver transplant surgery, however, the decision to postpone the procedure is very tough. The anesthesiologist is faced with a patient who has a delicate clinical status that may be worsened either by a MH crisis or by returning to the waiting list. All the medical team

2. **Call for help:** initiation of measures to treat MH, including the laborious process of dantrolene dilution, may be troublesome for one only anesthesiologist. Consequently the presence of another health professional (preferably an anesthesiologist) may be of

3. **Adjust ventilation:** increase minute ventilation to lower EtCO2 and use 100% oxygen.

4. **Administer the antidote:** Dantrolene is the drug of choice in treatment of malignant hyperthermia127. The contents of each bottle should be diluted in 60 mL of sterile water rather than solutions such as 5 percent dextrose in water or bicarbonate because the extra molecules in solution lead to a salting-out effect with greater difficulty in dissolving dantrolene. If it does not dissolve immediately, producing a clear yellow to yellow-orange color, it should be heated under tap water or autoclaved for a few minutes128. In a dire emergency, it should be administered through a blood filter without concern for crystals. Dantrolene should be preferentially administered through a large bore peripheral or central venous access to avoid local inflammatory phlebitis at

General dosing regimens recommend an initial bolus of 2.5 mg.kg-1, which can be repeated every 5 minutes until normalization of the hypermetabolic state and the disappearance of all MH symptoms. After this initial control, a continuous intravenous dantrolene infusion at 10 mg.kg-1.day-1 should be given for at least 24 h after initial

Although this is the classical regimen, it may be excessive and deleterious in liver transplantation patients. In this scenario, although the diseased liver is removed and a new liver graft is transplanted, the transplanted liver unavoidably sustains warm, cold, and reperfusion injuries during graft procurement and transplantation129. Dantrolene sodium is considered hepatotoxic and the hepatic effects of dantrolene on such liver allografts are unknown. As a result, it seems prudent to use the lowest effective dose for

There are two published case reports of MH in liver transplantation, with identical clinical presentation and successful treatment with lower than usual dantrolene doses56,96. One of the reports used a 1 mg.kg-1 dose intraoperatively, followed by 1 mg.kg-1 every eight hours for 36 hours; the authors observed signs of hepatic

There is no need to change the breathing circuit or the soda lime canister126.

**4.6 Management and treatment of MH during anesthesia for liver transplantation**

In the acute phase of MH the following steps are recommended:

**4.6.1 Intraoperatively**

valuable help.

the infusion site.

successful therapy76.

the shortest time possible.

prevention of complications124-125.

should be involved in this sentence.

dysfunction 9 days after the transplant, which was attributed to dantrolene and had spontaneous resolution56. In the other report, the same intraoperative dose was used (1 mg.kg-1) and no maintenance dose was used; in this case, no signs of liver graft dysfunction were observed96.

Therefore, to minimize the risks of graft toxicity by dantrolene, it seems prudent to adopt intraoperative doses of 1 mg.kg-1, which may be repeated every 30 minutes until control of symptoms. Next, the patient should be closely observed for MH recrudescences; if these occur, a regimen of 1 mg.kg-1 every eight hours for 36 hours should be instituted.


**5. Conclusion**

*Epilepsy - Advances in Diagnosis and Therapy*

3 Spatial

4 Frequency

5 Frequency

*Summary of EEG analyses.*

domain (EEG segments)

domain DWT (db1,db2)

domain db2 at level 4

**Analysis Database LoD Number of**

*LoD, Level of decomposition; Tr, Training.*

*Time complexity of EEG analyses.*

6 Db2 at level 4 8 statistical features, 4

have been examined for seizure detection.

calculations, the analyses prove that the performance of SVM with significant features is good when compared with ANN using large number of features as the input. The major contributions of these analyses in view of the existing work are as follows:

1.Two different machine learning algorithms (ANN and SVM) that are based on two different learning methods (error correcting and associative learning)

2.Unique set of features are extracted from the EEG signals for classification.

3.For optimization, genetic algorithm is used for feature selection and proved

4.Accuracies are calculated for raw EEG signal and for all decomposed signals

(GLCM and statistical) SVM (Linear

**Number of features significant**

4 12 12 SVM — 0.09

 Bonn University 3 10 6 ANN 243 0.123 Bonn University 3 10 6 SVM 64 0.023 Bonn University 4 6 6 ANN 184 0.2 Bonn University 4 6 6 SVM 61 0.02 Real-time data 4 16 12 SVM 63 0.0013 Real-time data 4 8 4 SVM 62 0.0011 Validation 4 8 4 SVM — 0.017

and RBF kernel)

ANN and SVM

Linear kernel (99.95%

Db2 wavelet and hybrid features to SVM classifier are the best outcomes (92.16%

accuracy (99.9 accuracy)

successful result with 90% performance accuracy in system validation

accuracy)

accuracy)

SVM Renyi entropy gives better

SVM Relevant features give

**Classifier Tr time**

**(seconds)**

**Test Time (seconds)**

that the classifier can perform well with relevant features.

**EEG analysis #: Domain Feature extraction Classifier Conclusion** 1 Spatial domain GLCM features ANN 85% Accuracy 2 Spatial domain GLCM features SVM 90% Accuracy

> GLCM, statistical, and hybrid features

Entropy estimation (Shannon, Renyi, and

GLCM features, 4 Renyi entropy estimation (Genetic algorithm for feature selection)

Tsallis)

**features**

**204**

**Table 6.**

**Table 5.**

An epileptic seizure is a symptom due to abnormal and excessive irregular neuronal activity in the brain. EEG test is mainly used for diagnosing epilepsy. EEG includes different types of waveforms with different frequency, amplitude, and spatial distribution. Traditional ways of computations would be less efficient for problem-solving. But, soft computing methods can work in an efficient way for discovering solutions from the given data. Components of soft computing are essential for developing automated expert systems. Early diagnosis of disease can save the life of a person. The approved CAD system is able to provide accurate results. Problem-solving is a challenging task for intelligent entities. It has been proved that "a machine can learn new things." It can adapt to new situations and has an ability to learn from the storage information. Supervised learning technique is used in majority of analyses. Fuzzy logic gives multi-value answers, whereas in machine learning, the system learns from data especially with the control or supervisor. In computational intelligence, evolutionary algorithms are inspired by biological systems and give optimal solution for the problem. "Clean data are greater than more data." Machine learns from data. Quality of data is important rather than quantity of data. This chapter gave an introduction about the components of soft computing and classification in machine learning. From the review of analyses, this chapter concludes that relevant features and less number of features can make the classifier perform well. Accuracies are compared in all decomposed signals and proved that level 4 of decomposition is enough for EEG signal classification. At level 4, the lower frequencies (delta and theta) can be analyzed perfectly because seizures occur mostly at lower frequencies. Also, from the analyses, it has been proved that the time required and memory space for data parameters are less.


*4.1. Compression of Aerial Images*

Three lossy compression algorithms were selected for the initial experiment: JPEG200, ECW, JPEG. As the quality of the compressed image depends not only on the compression algorithm but also on the compression ratio, four compression ratios were selected for each algorithm named as follows: low (25:1), medium (50:1), high (75:1), very high (100:1). The influence of the compression ratios lower than 25:1 is negligible, as shown in [19,31,34]. Higher compression ratios deteriorated image quality significantly and were not estimated in this work. Larger intervals between compression ratios were chosen to make their effect on the content of an image more explicit. Each algorithm introduces unique artifacts to the image content that are more noticeable in the higher compression ratios.

The GLOBAL MAPPER software [46] was used for the ECW compression of the original aerial images. The RGB color *\*.tiff* image file saved as the *\*.ecw* image using Global Mapper changing the compression ratios. The *imwrite()* function from MATLAB was used for JPEG2000 and JPEG compression. The source images were obtained as TIFF images with lossless compression. The JPEG2000 compressed files were generated using the *imwrite (* . . . *, "CompressionRatio", Value)* function, altering *Value* for the target compression ratio. For JPEG compression *imwrite (* . . . *, "Quality", Value)* function was used, altering *Value* as the quality from 100 to 1 of the JPEG compressed file. The smaller the number, the more compression will be reached with the worse quality for the image. All other settings for the *imwrite()* function were set to default values. The experimental compression ratios were tailored and verified using Equation (1).

The content and resolution of the image also affect the result of the lossy compressed image. Relevant compression algorithms have different effects on image textures, colors, and luminance. Three high-resolution (1 pixel = 0.5 m) aerial images of different content were selected using Earth Explorer [76]. The aerial images used in the experiment (Figure 4) are "img1", "img2", and "img3" of the dataset *200710\_myrtle\_beach\_sc\_0x5000m\_utm\_clr*, saved as 3000 × 3000 24-bit TIFF images in RGB (8 bits for each band). The "img1" has more smooth textures with low spatial frequencies of intensity changes, and the large regions of different colors and intensities dominate in it. The "img2" is rich with similar rough textures with high spatial frequencies of intensity changes, and small regions occupy a slight part of the image. The "img3" has various types of textures, and a large number of regions differ in size, color, and intensity [27]. We have tested other images with similar textures and colors to verify objective qualitative parameters. Images were selected by the varying characteristic features (texture, color tone, luminance, number, and size of the objects) but not by the appropriate classes, as the aim is to verify the methodology.

For the other three images of different resolutions, the original images were reduced four times using the *impyramid()* MATLAB function. The reduced "img1", "img2", and "img3" will be referenced as "img4", "img5", and "img6" accordingly, with the resolution of 1 pixel = 2 m and the size of 750 × 750 pixels. The remote sensing images with higher spatial resolution have richer spatial textures as their pixels contain more information compared to low-resolution images. All six images of different structures were compressed using three different algorithms using four compression ratios. Figure 5 presents the cropped images "img1" and "img4" compressed using JPEG2000, ECW, and JPEG algorithms at a 100:1 compression ratio.

**Figure 4.** The original aerial images used in the experiment (Landsat-7 images courtesy of the U.S. Geological Survey): (**a**) "img1" in RGB. The red rectangular indicates a cropped region presented in Figure 5); (**b**) "img2" in RGB; (**c**) "img3" in RGB; dataset *200710\_myrtle\_beach\_sc\_0x5000m\_utm\_clr*. (**d**) "img1", component Y; (**e**) "img2", component Y; (**f**) "img3", component Y.

**Figure 5.** The same cropped region of the aerial images "img1" and "img4" compressed using different lossy compression algorithms at the compression ratio 100:1: (**a**) "img1", the original image; (**b**) "img1", Joint Photographic Experts Group (JPEG)2000 compression; (**c**) "img1", Enhanced Compression Wavelet (ECW) compression; (**d**) "img1", JPEG compression; (**e**) "img4", the reduced "img1"; (**f**) "img4", JPEG2000 compression; (**g**) "img4", ECW compression; (**h**) "img4", JPEG compression.


**About the Editor**

**Bae Hwan Lee** is a professor at the Department of Physiology, Yonsei University College of Medicine, Republic of Korea. He received his Ph.D. degree at Korea University in 1993. In 1993, he started his academic career at University of Texas Medical Branch at Galveston, Texas, USA as a post-doc. He became an assistant professor in 1997, an associate professor in 2002, and a professor in 2007 at the Yonsei University College of Medicine. He received Awards for Excellent Papers from Korean Society for Brain and Neural Science in 2008 and from Korean Journal of Physiology & Pharmacology in 2014. He also received Achievement Awards from Korean Society for Brain and Neural Science in 2009 and from Korean Society for Emotion and Sensibility in 2017 for his outstanding service and invaluable contributions to the societies. He is an author of more than 150 scientific publications. His current research focuses on neural injury and functional recovery from cellular levels to behaviors.


**3.3 Technique: collection of smear**

	- a.Alcohol (70%) is adequate for fixation. Equal parts of ether and 95% ethyl alcohol give superior staining qualities.
	- b.Immediately immerse the slide in fixative or put the fixative on the slide with a dropper. Do not allow any drying of the smear before fixation.
	- c.Keep the slide in fixative for a minimum of 30 min.
	- d.At this point, the slides can be air dried and sent for staining and screening, or it can be left in the fixative.

#### *3.3.2 Advantages*

Deeper lesions are not identified by this technique, and for that another technique called fine needle aspiration cytology (FNAC) is used.


*2.2. PPI Network Construction and Identification of Hub Genes*

The 371 core targets were introduced into the STRING database to build the PPI (Protein-Protein Interaction) network of genistein's action against human cervical cancer. A confidence score of protein and protein interaction of >0.9 was set, and data were collected and visualized using Cytoscape. As shown in Figure 2, the network contained 317 nodes and 1754 edges; the cluster coefficient was 0.33, and the network centralization value was 0.170. The top 10 hub genes in this network were subsequently identified by MCC (Maximal Clique Centrality) algometrical analysis: FN1, TIMP1, GAS6, IL6, C3, IGFBP3, IGFBP4, IGFBP1, CST3 and SPP1. The increasing significance of genes in the network is represented by the color change (yellow to red) (Figure 3).

**Figure 2.** PPI network of the core genes in genistein's action against human cervical cancer (dark purple color indicates high degree; grey color indicates low degree).

**Figure 3.** Hub gene analysis of the PPI network. The color change from yellow to red indicates the increasing importance of related genes in the network. The red color indicates the highest significance.

#### *2.3. GO Enrichment Analyses of Core Targets*

The predicted core targets were further analyzed by GO (Gene Ontology) and KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway enrichment in the DAVID database. The top 20 biological processes of predicted core targets were identified (Figure 4A); the core targets are mainly involved in the response to organic substances, regulation of programmed cell death, regulation of cell death, regulation of apoptosis, response to endogenous stimulus, regulation of cell proliferation, response to hormone stimulus, and response to extracellular stimulus. The enriched KEGG pathways (Figure 4B) included the following: pathways in cancer; the p53 signaling pathway; the cell cycle; apoptosis; the MAPK (Mitogen Activated Protein Kinase) signaling pathway; the TLR (Toll Like Recepter) signaling pathway; and focal adhesion. From the hub gene analysis, FN1 was selected as the most significant hub gene in genistein's action against the cervical cancer network. Therefore, we predicted that the focal adhesion pathway is a novel pathway targeted by genistein in the treatment of cervical cancer. To gain a deeper insight, all the predicted genes in this pathway potentially regulated by genistein are highlighted in red (Figure 5).

**Figure 4.** GO ontology and KEGG pathway enrichment of the core targets. (**A**) Biological processes and (**B**) KEGG pathways involved in genistein's action against human cervical cancer.

**Figure 5.** Predicted targets of genistein's action in the focal adhesion pathway. Proteins highlighted in red indicate potential targets of genistein's action against human cervical cancer.

#### *2.4. Genistein Attenuates Cell Viability and Growth in HeLa Cells*

According to in silico studies, genistein showed multiple effects on cervical cancer. Next, we experimentally validated these effects using human cervical cancer cells in vitro. The high−risk HPV 16 and 18 are highly associated with the pathogenesis of cervical cancer. Moreover, according to the literature, HeLa cells are more sensitive to genistein treatment. Therefore, in this study, we used HeLa cells for the following experiments [27]. As shown in Figure 6A, genistein significantly inhibited cell growth in a time- and dose-dependent manner after 24 h and 48 h of treatment by CCK−8 (Cell Counting Kit−8) assay. Moreover, 5-fluorouracil (5−FU), clinically used as an anti-tumor drug, was used as a positive control. The concentration of 5−FU was chosen based on the literature [28]. The result showed that 80 μM of 5−FU inhibited the viability of HeLa cells compared with the DMSO (Dimethyl sulfoxide) control. The results indicate that genistein exerted the same inhibitory effect on the human cervical cancer cells as the anti-cancer drug 5−FU. Moreover, we further tested the effects of genistein on cell growth by using cell number counting. The results indicate a prominent effect of genistein on cell growth; the cell number was significantly decreased after genistein (12.5–100 μM) treatment for 24–48 h (Figure 6B). Furthermore, genistein strongly inhibited the colony formation ability of cervical cells (Figure 6C). While cervical cells formed large colonies in the control group, this colony-forming ability was significantly decreased after genistein treatment, indicating that genistein (12.5–100 μM) strongly inhibited HeLa cells' proliferation. Overall, these results demonstrate that 12.5–100 μM genistein strongly inhibited HeLa cells' viability and proliferation.

**Figure 6.** (**A**). Effects of genistein treatment on the proliferation of HeLa cells for 24–48 h were detected by CCK−8 assay. (**B**). Effects of genistein treatment on cell growth were counted by hemocytometer after 24–48 h. (**C**). Representative images of HeLa cell colony formation after genistein treatment (0–100 μM). The data shown are the average of three replicates; the experiments were performed three times independently. \*\*\* *p* < 0.001, \*\* *p* < 0.01, \* *p* < 0.05 compared with solvent control. Scale bar: 200 μm.

#### *2.5. Genistein Inhibits HeLa Cell Adhesion*

Since adhesion is the first critical step in cancer metastasis, we initially investigated the influence of genistein on HeLa cells' adhesion. The data demonstrate that genistein dosedependently inhibited cell adhesion in cervical cancer cells (Figure 7A,B). Compared to the control, 92%, 82%, 81%, and 71% inhibition of adhesion was observed with 12.5 μM, 25 μM, 50 μM, and 100 μM of genistein, respectively. Thus, HeLa cell adhesion was significantly inhibited after genistein (25–100 μM) treatment (*p* < 0.01; *p* < 0.05) (Figure 7A).

**Figure 7.** Effects of genistein on HeLa cell adhesion. Cells were grown in the presence of different doses of genistein for 24 h, and reseeded for 3 h. Adherent cells were then fixed by PFA (Paraformaldehyde) and stained with crystal violet solution. Absorbance readings were detected at OD570 nm by microplate reader. (**A**). Percentage of adhesion was then calculated based on the OD value of the adhered cells in the genistein-treated group (compared to control values (100%)). The experiment was performed three times independently, and data shown are the average of all three replicates. (**B**). Representative images from the three independent experiments. \*\* *p* < 0.01 vs. DMSO control; \* *p* < 0.05 vs. DMSO control. Scale bar: 200 μm.


**3. Results**

The literature search found 163 relevant articles, of which 152 did not meet the defined inclusion criteria. These studies were excluded based on the focus on other physical activities rather than strength-related ones, such as running performance, anthropometric characteristics, or strength evaluation performed in participants of other chronological ages including children. Consequently, a total of 11 studies were considered for further analysis. These studies were published between 2009 and 2020. The studies focus on the results that different types of warm-ups may cause in resistance training (**Table 1**).

*Warming-Up for Resistance Training and Muscular Performance: A Narrative Review DOI: http://dx.doi.org/10.5772/intechopen.96075*

**Table 1.**

*Main characteristics of studies.*


**Author details**

Gabriela Álvares-Pereira1 \*, Carolina Maruta2 and Maria Vânia Silva-Nunes1

1 Institute of Health Sciences, Centre for Interdisciplinary Research in Health, Universidade Católica Portuguesa, Lisbon, Portugal

2 Faculty of Human Sciences, Católica Research Centre for Psychological, Family and Social Wellbeing, Universidade Católica Portuguesa, Lisbon, Portugal

\*Address all correspondence to<EMAIL_ADDRESS>
© 2022 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

*The Role of Cognitive Reserve in Executive Functioning and Its Relationship to Cognitive Decline… DOI: http://dx.doi.org/10.5772/intechopen.104646*


Contents

#### **Preface XI**

Chapter 9 **Skin Cancer Screening 249** Carolyn J. Heckman, Susan Darlow, Teja Munshi and Clifford Perlis

Preface

Since the middle of the 20th century, the incidence of skin cancers such as malignant mela‐ noma is increasing most in the Caucasian population, doubling every 10 years to reach the current rate of 10-15 new cases per year per 100,000 inhabitants. Epidemiological models suggest that prediction is that now a person out of 75 is likely to develop a melanoma in his

Along with the increased incidence, increased mortality secondary to melanoma was ob‐ served in the second half of the twentieth century, followed by a stabilization probably related to efforts in primary and secondary prevention. Therapeutic advances in this area have been quite limited until recently , despite the enthusiasm generated by clinical trials of immuno‐ therapy, and encourage further efforts to organize prevention and screening compaigns.

Prevention and detection of skin cancer and melanoma in particular are important public health goals in order to decrease the impact of these frequent tumours in young patients. These objectives require particularly strong solidarity between GPs and dermatologists, both

Despite the fact that new recent progress in skincancer treatment have been described, and that new targeted molecules or new therapeutic procedures help our patients, new insights regarding skin biology are also needed to develop new strategies. Moreover interactions be‐ tween dermatologists and oncologists are mandatory: many targeted therapies developed to treat systemic malignancies have shown important efficacy for the treatment of both cutane‐ ous malignancies and non-malignant skin disease, such as Hedgehog inhibition for basal

This Highlights in Skincancer written by leading experts in their field synthesize common skincancer topics in clinics and research. It is not a guide intended to be a comprehensive and exhaustive review of all the aspects of dermato-oncology but really a companion that should help the clinicians and researchers to find important and specialized information in this field. It is also an awareness of the close collaboration that must exist between dermatol‐

Cliderm, European Institute for Dermatology Practice and Research,

**Pierre Vereecken, MD, PhD**

Chirec Cancer Institute, Brussels, Belgium

in firstline for the evaluation of the skin of patients and to detect their risk factors.

lifetime. Cutaneous carcinomas are also more frequent.

cell carcinoma and Rituximab for Pemphigus Vulgaris.

ogists and medical oncologists in the management of our patients.

#### Chapter 10 **The Role of Furin in the Development of Skin Cancer 271** Rethika Ravi and Terrence J Piva


**2. Materials and methods**

As described in Section 1, the GOALS system has been specifically developed for the use of an opto‐electronic stereo‐photogrammetric measurement approach within a clinical environ‐ ment. This project stems from over 25 years of biomechanical‐clinical research conducted by our research group having in mind the following three specific 'GOALS':

2 NaturalPoint Inc., OR, USA.

(3) Represent the results in clinical and intuitive manner, with strict biomechanical princi‐ ples, but at the same time hiding the weight of complex mathematical methods involved.

To meet the above points, we have developed an adjustable body skeleton model, which automatically adapts to the measures of the subject. To allow the use of this method in a simple and quick way in daily clinical practice, the model was designed with the intention to maintain the smallest possible number of body landmarks.


**3.3. Social factors**

can result in cell injury.[46] The degree of mitochondrial toxicity is specific to each NRTI. Theoretically, an HIV-infected person's fertility may be affected by NRTI use via the damage

in sperm and oocytes of HIV-infected patients taking NRTIs and in low oocyte mtDNA in patients with ovarian insufficiency.[47-49] Data from epidemiologic studies are conflicting regarding the impact of cART on fertility. A prospective cohort from the United States reported the lower likelihood of conception associated with antiretroviral therapy among HIV-infected women,[5] whereas a more recent study from Africa demonstrated significantly higher pregnancy rates among HIV-infected women on cART compared to those not on cART.[50] However, these two studies were conducted in different settings and time, and specific behavioral and biological mechanisms were not explored. Zidovudine (azidothymidine, AZT) is the NRTI drug that has been studied the most. In animal studies, AZT has been shown to suppress cell division in the preimplantation mouse embryo, causing reduction in inner cell mass proliferation, greater number of resorptions, and fewer fetuses.[51, 52] A previous study demonstrated that exposure to NRTI transplacentally caused significant fetal mitochondrial damage in experimental monkeys.[53] Unfortunately, there have been no studies examining

Decrease in sexual activity after a new diagnosis of HIV infection is usually observed and may be accompanied by the feeling of guilt and shame and aggravated by the stigma related to HIV infection.[54] Individuals recently diagnosed with HIV infection reported to have decreased desire for or interest in sex relations. They also reported to use condom more consistently during sexual intercourse to avoid transmission of HIV to their partners.[55] Previous studies indicated that HIV-infected women often chose to avoid pregnancy.[56, 57] However, another study revealed that high-risk behaviors, unplanned pregnancies, and pregnancy termination remain prevalent among this population.[58] In the pre–cART era, there was a significant increase in the pregnancy termination rate from 3.5 to 6.3 per 100 women-years following a new HIV diagnosis in the United Kingdom and Ireland[56] and 47% of pregnancies were voluntarily terminated following a new HIV diagnosis in an Australian study.[57] The reasons for pregnancy termination may include challenges of pregnancy, birth and parenting in the context of HIV infection, concerns about increased risks of complications related to pregnancy and delivery, and risk of HIV transmission to the newborn. A previous study reported that unplanned pregnancy, lower CD4 cell count, and having an HIV-infected current partner were factors associated with the decision to terminate a pregnancy.[59] Following the introduction of cART with overall improvement in health and immune status of HIV-infected women, the rates of elective pregnancy termination after a HIV diagnosis were 22%-26% decreased from the pre–cART period.[60, 61] With the success of cART in preventing mother-to-child HIV transmission, HIV infection was reported to have no effect on desire for pregnancy among young urban African Americans aged 15–24 years.[62] Reproductive desire among PLWHIV may now be associated with personal health, cART, concern about HIV transmission, and

This is supported by the mtDNA depletion observed

to mitochondrial biogenesis of gametes.3

184 Genital Infections and Infertility

fertility effect of NRTIs in humans.

**3.2. Psychological factors**

The HIV/AIDS epidemic has a significant impact on the economic and political stability of a nation. Awareness of HIV/AIDS at the population level may affect the age of sexual debut, frequency of sexual intercourse, safer sex and contraceptive practices, perceived value of marriage, social norms, and fertility intentions and choices of PLWHIV.3 The dramatic improvement in the life expectancy of PLWHIV and reduction in HIV transmission rates following treatment of the infected partner have changed ethical considerations regarding childbearing in HIV-infected individuals. Early in the HIV/AIDS epidemic, pregnancy in HIVinfected women was considered morally problematic, whereas recently, the Ethics Committee of the American Society for Reproductive Medicine stated that it is ethical for health care providers to assist PLWHIV who seek pregnancy when optimal precautions to prevent HIV transmission are utilized.[66] Despite more opportunities for access to reproductive care, PLWHIV still face multiple obstacles. First, the severity of their disease, level of immunosup‐ pression, presence of OIs, and other comorbid diseases may impair their fertility. Second, their HIV provider may have limited knowledge to counsel them on reproductive health issues, and infertility specialists may have limited expertise in providing care for HIV-infected persons. Third, HIV stigmatization could potentially preclude them from establishing reproductive care. Finally, assisted fertility therapy (AFT) is technically complicated in regard to HIV transmission prevention and costliness and may not be available in all settings.[3]


*Article* **Transcriptomic Analysis of** *Betula halophila* **in Response to Salt Stress**

#### **Fenjuan Shao 1 , Lisha Zhang 1 , Iain W. Wilson 2 and Deyou Qiu 1,\***

Received: 9 October 2018; Accepted: 25 October 2018; Published: 31 October 2018

**Abstract:** Soil salinization is a matter of concern worldwide. It can eventually lead to the desertification of land and severely damage local agricultural production and the ecological environment. *Betula halophila* is a tree with high salt tolerance, so it is of importance to understand and discover the salt responsive genes of *B. halophila* for breeding salinity resistant varieties of trees. However, there is no report on the transcriptome in response to salt stress in *B. halophila*. Using Illumina sequencing platform, approximately 460 M raw reads were generated and assembled into 117,091 unigenes. Among these unigenes, 64,551 unigenes (55.12%) were annotated with gene descriptions, while the other 44.88% were unknown. 168 up-regulated genes and 351 down-regulated genes were identified, respectively. These Differentially Expressed Genes (DEGs) involved in multiple pathways including the Salt Overly Sensitive (SOS) pathway, ion transport and uptake, antioxidant enzyme, ABA signal pathway and so on. The gene ontology (GO) enrichments suggested that the DEGs were mainly involved in a plant-type cell wall organization biological process, cell wall cellular component, and structural constituent of cell wall molecular function. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment showed that the top-four enriched pathways were 'Fatty acid elongation', 'Ribosome', 'Sphingolipid metabolism' and 'Flavonoid biosynthesis'. The expression patterns of sixteen DEGs were analyzed by qRT-PCR to verify the RNA-seq data. Among them, the transcription factor AT-Hook Motif Nuclear Localized gene and dehydrins might play an important role in response to salt stress in *B. halophila*. Our results provide an important gene resource to breed salt tolerant plants and useful information for further elucidation of the molecular mechanism of salt tolerance in *B. halophila*.

**Keywords:** *Betula halophile*; salt stress; transcriptomes


**2. Methods**

*Cardiorespiratory Fitness*

There is great variability in cognitive aging among individuals, given the heterogeneity of biological, socioeconomic, cultural, and environmental aspects which can modulate this process. Advanced activities of daily living (AADLs) are a set of leisure activities performed on free time, independently from work, which includes volunteering, educational activities, and social participation in the community, being this dependent on personal motivation. The effects of retrogenesis are a natural process to which every individual may or may not pass, due to a number of circumstances. The effects arising from retrogenesis are cognitive and motor slowness, followed by behavioral and psychic changes, with structural and functional changes taking place, causing neural impoverishment and irreversible functional decline, which cannot be regarded as a disease but rather as a natural aging process that subsequently will induce a new process, which will form a new organization for compensating for cognitive declines [1, 2] of psychomotor function, attention, visual learning and working memory (MT). These cognitive domains are fundamental variables for a healthy life for us human beings, the psychomotor function. In gerontological literature, AADLs may indicate good physical and mental health,

and reduced engagement in these activities may suggest the onset of functional decline, cognitive impairment, and frailty. The science today aims to study the body in motion in relation to the world, with the conception of integrated and organized movements improving body movements as motor coordination, balance, and attention, which in turn is an essential skill for good adaptive and oriented functioning, are associated with the cognitive domain that enables the elderly to process all information or actions relevant to the thinking of certain tasks, leaving distracting and irrelevant stimuli aside [3], and constituting a facilitating mechanism for neural responses

according with the centralization of the mental processes of a given task [4].

conscious and safe voluntary motor action.

maintenance of cognitive skills in healthy elderly [6–8].

Rowe and Kahn [5] suggested that commitment to life is one of the essential aspects of successful aging and may delay the onset of chronic diseases and high physical and cognitive performance. Walking independently requires cognitive and motor processing whose mechanisms involved are related to attentional resources, executive functions, and the sensory and musculoskeletal systems. It is a consensus in the literature that locomotion is a factor directly related to the preservation of physical independence, performance of activities of daily living, and social interaction. The visual learning in the elderly has a key role in motor development, placing it with the external reality, providing various stimuli that help in orientation, and in their body control, enabling the ability to know, interpret, and differentiate various stimuli visually received. Vision has a direct participation in the organization and

Working memory enables the elderly to keep information in their mind at the moment they use it, searching for information relevant to their activities and performing other tasks, such as the relationship of different ideals, such as mental calculations, ordering and sequencing current and past events including consideration of facts or ideas that may come from different points of view. Once this decline is detected through testing, then we can organize cognitive and physical exercises to maintain a healthy life for the elderly and research on cognitive interventions indicating that cognitive training can lead to increased performance and

Aging is a natural and inherent process, being associated with several physical, physiological, psychological, and social changes. Among these changes, there is a decline in cognitive performance, being negatively associated with age and cognitive degenerative diseases such as Alzheimer's disease, causing impairment in the

**1. Introduction**

**80**

### **2.1 Detection test**

The detection test uses a simple reaction time paradigm to measure processing speed in healthy volunteers in just 3 min and cognitive domain and psychomotor function. The detection test is applied with the supervision, in this case, the researcher. The test includes virtual card by computer, iPad, or tablet, universally understood, regardless of language or age; after reading, the test is started by pressing the "enter" key. In the center of the screen, a sequence of cards will appear, and the volunteer has to press the "yes" key, whenever the presented card is correct, as quickly and accurately as possible, for example, should try not to press the "yes" key. Before the card is flipped, if this happens or is not answered, this time is counted, and you will hear an error sound.

The average reaction times are transformed by the log10 unit of measurement for correct answers. The result of the detection test is the average reaction time to which the elderly responded correctly; a higher value indicates a slower response.


**Author details**

Ederson Augusto Zanetti1 \*, Frederick N. Numbisi2 , Vithal Karoshi3 , Roberto Rochadelli4 , Allan Sbardelotto5 , Joesio Siqueira6 and Alain Levy Boussamba7

1 Green Farm CO2FREE, Curitiba, Parana, Brazil

2 Independent Researcher, Freiburg in Breisgau, Auggen, Germany

3 Lilongwe University of Agriculture and Natural Resources (LUANAR), Lilongwe, Malawi

4 Federal Paraná University (UFPR), Coordinator of "MRV-FUPEF Programm", Curitiba, Parana, Brazil

5 Independent Researcher, Rio Branco, Acre, Brazil

6 STCP Engenharia de Projetos, Curitiba, Parana, Brazil

7 ONG Humanitas, Libreville, Gabon

\*Address all correspondence to<EMAIL_ADDRESS>
© 2023 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


3.1.2. Consistency Limits

The consistency limits of the soil used presented the plasticity index (PI) values in Table 2. Thus, it was possible to verify that the values were adequate, since the PI for the production of soil-cement bricks should be up to 18%, as shown in studies [45,46]. In addition, the results reached the reference values for the manufacture of soil-cement bricks, i.e., soils with the maximum limit of 45% for liquidity limit (LL) and 18% for plasticity limit (PL), as well as those recommended by the ABNT standard [35].

\* Liquidity Limit (LL), Plasticity Limit (PL) and Plasticity Index (PI).

Differently from the results of the soil (reference sample), the values of the PET-Soil cement mixtures showed decreased LL, PL and PI compared to natural soil. This occurred due to the addition of PET waste (sandy fraction), showing that with an increase in the percentage of addition, the greater the amount of water needed in the mixture to get out of its plastic state. This can be related to the workability of the mixture, i.e., the greater the amount of water added, the lower the workability of the mixture [47,48].

## 3.1.3. Moisture Content and Compaction Energy

The optimum compaction moisture results with the respective maximum densities of the mixtures are presented in Table 3.

**Table 3.** Optimum compaction humidity and maximum mixture densities.

The results in this table showed that with the increase of PET waste, there was an increase in the optimum moisture content of compaction and a decrease in the maximum specific weight. As for the decrease in maximum specific weight, this is due to the density value of the PET waste being lower than that of the natural soil. Moreover, the sample mass decreased as water was added to the compaction process because the waste did not have plastic properties. With this, as the water addition increased, it was possible to verify that the workability was decreasing, therefore this is also related to the compaction strength, as reported in study by Akinyele and Ajede [23]. The compaction curves of the mixtures are presented in Figure 4. Moreover, the curves proved (especially between 0% and 30%) the difference between the mixtures in relation to the addition of waste, i.e., the higher the percentage of addition, the greater the difficulty of reaching the optimum moisture content with increasing percentage of PET.

**Figure 4.** Compaction curves and optimum moisture of mixtures. Percentages (%) indicate the amount of water content in each mixture (0%, 10%, 20% and 30%).

3.1.4. Microstructural Characterization

A morphological analysis in Figure 5 by SEM showed that PET presents high surface area and irregularities in the shape and size of its particles. These are typical of different cutting and crushing processes of the waste, as shown in studies by Siqueira and Holanda [49]. As the particles present an irregular distribution, smaller sized particles can occupy the free spaces left by larger sized particles, forming particle packing [50].

**Figure 5.** Scanning Electron Microscopy (SEM) of PET 60× magnification.


**Chemical Composition and Biological Activities of Essential Oils**

Printed Edition of the Special Issue Published in *Antibiotics* Edoardo Marco Napoli and Maura Di Vito Edited by

www.mdpi.com/journal/antibiotics


**Mona Taghavikish 1, Naba Kumar Dutta 1,2,\* and Namita Roy Choudhury 1,2,\***

Academic Editor: Tony Hughes Received: 5 September 2017; Accepted: 2 October 2017; Published: 1 December 2017

**Abstract:** Corrosion is a deterioration of a metal due to reaction with environment. The use of corrosion inhibitors is one of the most effective ways of protecting metal surfaces against corrosion. Their effectiveness is related to the chemical composition, their molecular structures and affinities for adsorption on the metal surface. This review focuses on the potential of ionic liquid, polyionic liquid (PIL) and graphene as promising corrosion inhibitors in emerging coatings due to their remarkable properties and various embedment or fabrication strategies. The review begins with a precise description of the synthesis, characterization and structure-property-performance relationship of such inhibitors for anti-corrosion coatings. It establishes a platform for the formation of new generation of PIL based coatings and shows that PIL corrosion inhibitors with various heteroatoms in different form can be employed for corrosion protection with higher barrier properties and protection of metal surface. However, such study is still in its infancy and there is significant scope to further develop new structures of PIL based corrosion inhibitors and coatings and study their behaviour in protection of metals. Besides, it is identified that the combination of ionic liquid, PIL and graphene could possibly contribute to the development of the ultimate corrosion inhibitor based coating.

**Keywords:** ionic liquid; polyionic liquid; graphene; hybrid coating


*Article* **Historical Zooplankton Composition Indicates Eutrophication Stages in a Neotropical Aquatic System: The Case of Lake Amatitlán, Central America**

**Sarahi Jaime 1,\*, Adrián Cervantes-Martínez 1, Martha A. Gutiérrez-Aguirre 1, Eduardo Suárez-Morales 2, Julio R. Juárez-Pernillo 3, Elena M. Reyes-Solares 3 and Victor H. Delgado-Blas 1**

**Abstract:** This paper presents a study of freshwater zooplankton biodiversity, deemed as a reliable indicator of water quality. The Guatemalan Lake Amatitlán, currently used as a water source, has shown signs of progressive eutrophication, with perceptible variations of the local zooplankton diversity. Biotic and abiotic parameters were determined at four sites of Lake Amatitlán (Este Centro, Oeste Centro, Bahía Playa de Oro, and Michatoya) in 2016 and 2017. The local composition, the species richness and abundance of zooplankton, and the system environmental parameters were analyzed during both years surveyed. Biological data suggesting eutrophication of this tropical system were obtained, including a high rotifer abundance (11 species: the rotifers *Brachionus havanaensis* (109 ind L−1) and *Keratella americana* (304 ind L−1) were the most abundant species in this lake). The presumably endemic diaptomid copepod species, *Mastigodiaptomus amatitlanensis,* was absent in our samples, but we report the unprecedented occurrence of two Asian cyclopoid copepods (i.e., *Thermocyclops crassus* and *Mesocyclops thermocyclopoides*) for Lake Amatitlán and Guatemala. The presence of larger zooplankters like adults and immature copepods (i.e., *Arctodiaptomus dorsalis*) and cladocerans (*Ceriodaphnia* sp.) at site "Este Centro" indicates a relatively healthy zooplankton community and represents a focal point for managing the conservation of this lake.

**Keywords:** conservation; eutrophication; exotic species; tropical lakes; zooplankton


**3.3.2 Acceptance test of blue instances under RLP/T**

The question we ask now can be formulated as follows: "Given any occurring blue instance *B*, can *B* be accepted?". *B* will be accepted provided a valid schedule exists, i.e. a schedule in which *B* will complete within its deadline while all periodic instances previously accepted will still meet their deadlines. Let *τ* be the current time which coincides with the release of a blue instance *B*. *B*(*r*, *c*, *d*) is characterized by its release time *r*, its execution time *c* and its deadline *d*, with *r* + *c* ≤ *d*. We assume that the system supports several uncompleted blue instances at time *τ* previously accepted. Let's denote by B(*τ*) = {*Bi*(*ci*(*τ*), *di*), *i*=1 to *blue*(*τ*)}, 10 Will-be-set-by-IN-TECH

Consider the periodic task set T defined in Table 1. The relating RLP scheduling is illustrated in Figure 7. The number of deadline misses has been reduced to four. Missed deadlines occur at instants *t* = 36 (task *T*3), *t* = 54 (task *T*2) and *t* = 72 (tasks *T*1 and *T*3). Observe that the first blue instance *T*2 which failed to complete within its deadline under BWP scheduling (see Figure 4) has enough time to succeed under RLP scheduling. The execution of the first red instances of *T*1 and *T*0 is postponed. Red instances are scheduled as soon as possible until time *t* = 12 and execute as late as possible in the presence of blue instances from time *t* = 12

> ✻ ✻ ✲✻ ✻ ✻ ✻ ✻ ✻ ✻ ✻ ✻ ✻ ✻ ✻ ✻ ✻ ✻ ✻ ✻

0 36 72 0 24 48 72 0 18 36 54 72 0 12 24 36 48 60 72

The *Red tasks as Late as Possible with blue acceptance Test (RLP/T)* algorithm (Marchand & Chetto,

RLP/T runs as follows: red instances enter the system directly at their arrival time whereas blue instances integrate the system upon acceptance. A blue instance is scheduled as soon as possible together with red ones once accepted. All the ready instances are of the same importance. Deadline ties are broken in favor of the task with the earliest release time.

Processor idle times are computed according to the EDL strategy once a new blue instance is released. We assume that the instance immediately following a blue instance is also blue in the EDL schedule established at time *τ*. All blue instances previously accepted at *τ* are guaranteed by the schedulability test. It ensures there are enough idle times to accommodate

The question we ask now can be formulated as follows: "Given any occurring blue instance *B*, can *B* be accepted?". *B* will be accepted provided a valid schedule exists, i.e. a schedule in which *B* will complete within its deadline while all periodic instances previously accepted will still meet their deadlines. Let *τ* be the current time which coincides with the release of a blue instance *B*. *B*(*r*, *c*, *d*) is characterized by its release time *r*, its execution time *c* and its deadline *d*, with *r* + *c* ≤ *d*. We assume that the system supports several uncompleted blue instances at time *τ* previously accepted. Let's denote by B(*τ*) = {*Bi*(*ci*(*τ*), *di*), *i*=1 to *blue*(*τ*)},

2008) is an improvement of RLP designed to maximize even more the actual QoS.

up to the end of the hyperperiod. This enhances the actual QoS of periodic tasks.

Fig. 7. A schedule produced by the RLP scheduling algorithm (*si* = 2)

the new blue instance within its deadline, as described hereafter.

**3.3.2 Acceptance test of blue instances under RLP/T**

*: processing red instance : processing blue instance*

✻*: release time*

**3.2.2 Illustrative example**

*T*0 *T*1 *T*2 *T*3

**3.3 The RLP/T algorithm 3.3.1 Algorithm description** the blue instance set at time *τ*. The value *ci*(*τ*) is called *dynamic execution time* and represents the remaining execution time of *Bi* at *τ*. B(*τ*) is ordered such that *i* < *j* implies *di* ≤ *dj*.

Theorem 2 presents the acceptance test of blue instances within a system involving RLP skippable tasks. This test is based on theoretical results established in (Silly-Chetto et al., 1990) for the acceptance of sporadic requests that occur in a system composed of non-skippable periodic tasks.

**THEOREM 2.** *Instance B is accepted if and only if, for every instance Bi* ∈ B(*τ*) ∪ {*B*} *such that di* ≥ *d, we have δi*(*τ*) ≥ 0*, with δi*(*τ*) *defined as:*

$$\delta\_{\dot{l}}(\tau) = \Omega\_{\mathcal{T}(\tau)}^{EDL}(\tau, d\_{\dot{l}}) - \sum\_{j=1}^{\dot{l}} c\_{j}(\tau) \tag{6}$$

*δi*(*τ*) is called *slack of instance Bi at time τ*. It defines the maximum units of time during which *Bi* could be delayed without violating its deadline. Ω*EDL* T (*τ*) (*τ*, *di*) denotes the total units of time that the processor is idle in the time interval [*τ*, *di*]. The total computation time required by blue instances within [*τ*, *di*] is given by ∑*i j*=1 *cj*(*τ*).

The acceptance test is based on the computation of EDL idle times which gives the slack of any blue instances. Then, this slack is compared to zero. The acceptance test runs in *O*(� *R p* �*n* + *blue*(*τ*)) in the worst-case, where *n* is the number of periodic tasks, *R* is the longest deadline and *p* is the shortest period. *blue*(*τ*) denotes the number of blue instances at time *τ* whose deadline is greater or equal to the deadline of *Bi*. A specific updating of additional data structures with slack tables may reduce the complexity to *O*(*n* + *blue*(*τ*)) as proved in (Tia et al., 1994).

#### **3.3.3 Illustrative example**

✲ ✲ ✲

> Figure 8 gives an illustration of RLP/T scheduling for the periodic task set T defined in Table 1. Clearly, RLP/T improves on both RLP and BWP. Only three deadline violations relative to blue instances are observed: at instants *t* = 36 (task *T*3), *t* = 54 (task *T*2) and *t* = 72 (task *T*3). The acceptance test contributes to compensating for the time wasted in starting the execution of blue instances which are not able to complete before deadline. The blue instance *T*2 released at time *t* = 36 is aborted at time *t* = 54 – 8 units of time were indeed wasted – in the RLP case (see Figure 7). This rejection performed with RLP/T permits us to save time recovered for the successful completion of the blue instance *T*1 released at time *t* = 48.

#### **4. Performance analysis**

#### **4.1 Simulation details**

We report part of a performance analysis composed of three simulation experiments in order to evaluate RLP/T with respect to RTO, BWP and RLP.

We successively measure:

in the Firm Real-Time Systems 13

Quality of Service Scheduling in the Firm Real-Time Systems 203

The QoS observed for BWP, RLP and RLP/T is higher for a given processor utilization when the task's computation time is less than the task's worst-case execution time. As the amount of time given by *WCET* − *ACET* is not used by each instance, additional CPU time permits

Moreover, note that BWP and RLP outperform RLP/T for low overloads with ACET=0.75\* WCET. This comes from the admission test in RLP/T which uses WCET values and not ACET ones. Consequently, RLP/T rejects instances that after all could have been accepted on the basis of their ACET. This is exactly what we observe for *Up* equal to 130%: RLP/T temporarily offers lower performances than BWP and RLP. Note that this phenomenon is no

Finally, other tests (Marchand, 2006) – not reported here – show that the higher the skip factor is, the more significant the advantage of RLP/T over the other scheduling algorithms.

We study here the CPU time wasted in incomplete executions of blue instances. The

(a) *si* = 2 (b) *si* = 6

The wasted CPU time is equal to zero for RTO since all red instances execute successfully. It is also equal to zero under RLP/T for any CPU utilization. This is due to the admission test that prevents from the abortion of blue instances. A blue instance is accepted if and only if it

The wasted CPU time is always positive under BWP and RLP once the system is overloaded (*Up* > 1). BWP and RLP involve the largest wasted CPU time – 24% et 26% respectively – for *Up* = 115% and *si* = 2. The BWP and RLP curves present a decline beyond that load. More red instances have to be executed under high overload. Less available CPU time is consequently

Additional results reported in (Marchand, 2006) show that wasted CPU time is all the less

us to successfully complete a higher number of instances.

longer observable once the skip factors are higher (e.g. *si* = 6).

simulation results for *si* = 2 and *si* = 6 are depicted in Figure 10.

Fig. 10. Wasted CPU time for low and high skips

available for the execution of blue instances.

can complete before deadline.

significant as skip factors grow.

**4.1.2 Experiment 2**

Fig. 8. A schedule produced by the RLP/T scheduling algorithm (*si* = 2)

• *the CPU idle time ratio* (i.e. the percentage of time during which the processor is not processing any task).

We make the processor utilization *Up* vary. The simulator generates 50 sets of periodic tasks. Each set contains 10 tasks with a least common multiple of periods equal to 3360 time units. The tasks have a uniform skip factor *si*. Worst-case computation times depend on *Up*. Deadlines are equal to periods and greater than or equal to computation times. Simulations have been processed over 10 hyperperiods.

#### **4.1.1 Experiment 1**

Figure 9 depicts the simulation results for *si*=2. The results are given for an actual computation time (ACET) equal to 100% and 75% of the worst-case computation time (WCET) respectively. Let us recall that the tasks have variable actual computation times assumed to be less than an estimated worst-case computation time. The assumption that a task consumes its WCET in every activation is not necessarily true. This implies that the actual CPU utilization never exceeds the estimated one used in the schedulability test.

Fig. 9. QoS for *si*=2

BWP and RLP outperform RTO – for which the QoS is constant and minimal – for any processor workload. Both BWP and RLP succeed in completing all blue instances that respectively execute after and before red instances for *U p* ≤ 1. RLP and BWP give almost the same performances under overload. Nevertheless, RLP/T provides a significant improvement in performance compared with RLP.

The QoS observed for BWP, RLP and RLP/T is higher for a given processor utilization when the task's computation time is less than the task's worst-case execution time. As the amount of time given by *WCET* − *ACET* is not used by each instance, additional CPU time permits us to successfully complete a higher number of instances.

Moreover, note that BWP and RLP outperform RLP/T for low overloads with ACET=0.75\* WCET. This comes from the admission test in RLP/T which uses WCET values and not ACET ones. Consequently, RLP/T rejects instances that after all could have been accepted on the basis of their ACET. This is exactly what we observe for *Up* equal to 130%: RLP/T temporarily offers lower performances than BWP and RLP. Note that this phenomenon is no longer observable once the skip factors are higher (e.g. *si* = 6).

Finally, other tests (Marchand, 2006) – not reported here – show that the higher the skip factor is, the more significant the advantage of RLP/T over the other scheduling algorithms.

## **4.1.2 Experiment 2**

✲ ✲ ✲

12 Will-be-set-by-IN-TECH

• *the CPU idle time ratio* (i.e. the percentage of time during which the processor is not

We make the processor utilization *Up* vary. The simulator generates 50 sets of periodic tasks. Each set contains 10 tasks with a least common multiple of periods equal to 3360 time units. The tasks have a uniform skip factor *si*. Worst-case computation times depend on *Up*. Deadlines are equal to periods and greater than or equal to computation times. Simulations

Figure 9 depicts the simulation results for *si*=2. The results are given for an actual computation time (ACET) equal to 100% and 75% of the worst-case computation time (WCET) respectively. Let us recall that the tasks have variable actual computation times assumed to be less than an estimated worst-case computation time. The assumption that a task consumes its WCET in every activation is not necessarily true. This implies that the actual CPU utilization never

(a) ACET=WCET (b) ACET=0.75\*WCET

BWP and RLP outperform RTO – for which the QoS is constant and minimal – for any processor workload. Both BWP and RLP succeed in completing all blue instances that respectively execute after and before red instances for *U p* ≤ 1. RLP and BWP give almost the same performances under overload. Nevertheless, RLP/T provides a significant

*T*0 *T*1 *T*2 *T*3

processing any task).

**4.1.1 Experiment 1**

Fig. 9. QoS for *si*=2

*: processing red instance : processing blue instance*

Fig. 8. A schedule produced by the RLP/T scheduling algorithm (*si* = 2)

✻*: release time*

have been processed over 10 hyperperiods.

exceeds the estimated one used in the schedulability test.

improvement in performance compared with RLP.

✻ ✻ ✲✻ ✻ ✻ ✻ ✻ ✻ ✻ ✻ ✻ ✻ ✻ ✻ ✻ ✻ ✻ ✻ ✻

0 36 72 0 24 48 72 0 18 36 54 72 0 12 24 36 48 60 72

> We study here the CPU time wasted in incomplete executions of blue instances. The simulation results for *si* = 2 and *si* = 6 are depicted in Figure 10.

Fig. 10. Wasted CPU time for low and high skips

The wasted CPU time is equal to zero for RTO since all red instances execute successfully. It is also equal to zero under RLP/T for any CPU utilization. This is due to the admission test that prevents from the abortion of blue instances. A blue instance is accepted if and only if it can complete before deadline.

The wasted CPU time is always positive under BWP and RLP once the system is overloaded (*Up* > 1). BWP and RLP involve the largest wasted CPU time – 24% et 26% respectively – for *Up* = 115% and *si* = 2. The BWP and RLP curves present a decline beyond that load. More red instances have to be executed under high overload. Less available CPU time is consequently available for the execution of blue instances.

Additional results reported in (Marchand, 2006) show that wasted CPU time is all the less significant as skip factors grow.

in the Firm Real-Time Systems 15

Quality of Service Scheduling in the Firm Real-Time Systems 205

CLEOPATRE components have been prototyped under *Linux/RTAI (Real-Time Application Interface)* (Racciu & Mantegazza, 2006) and distributed under the LGPL license. The LGPL allows proprietary code to be linked to the GNU C library, glibc. When a program is linked with a library – whether statically or using a shared library – the combination of the two is legally speaking a combined work, a derivative of the original library. Companies do not have to release the source to code that which has been dynamically linked to an LGPLed library.

The CLEOPATRE library offers selectable COTS (Commercial-Off-The-Shelf) components dedicated to dynamic scheduling, aperiodic task servicing, resource control access, fault-tolerance and QoS scheduling. An additional task named *TCL (Task Control Logic)* interfaces all the CLEOPATRE components and has the highest priority. It has been added as a dynamic module in \$*RTAID IR*/*modules*/*TCL*.*o* and interfaces with the legacy RTAI

The CLEOPATRE interface is totally independent from the RTAI core layer. It can be directly used with Xenomai – which supports the RTAI API – and easily adapted to any other real-time

CLEOPATRE applications are highly portable to any new CPU architecture thanks to this OS abstraction layer which makes the library of services generic (Silly et al., 2007). The CLEOPATRE Off-the-Shelf components are optional except for the OS abstraction layer (TCL) and the scheduler. At most one component per shelf can be selected. Since all components of a given shelf have the same programming interface, they become interchangeable. Everything needed to use or extend CLEOPATRE can be downloaded from the project web

The memory and disk footprints of the operating system turn out to be key issues for embedded real-time applications as well as the time overhead incurred by the operating system itself. Table 2 gives the footprints for the schedulers provided by CLEOPATRE.

scheduler defined in \$*RTAID IR*/*modules*/*rtai*\_*sched*.*o*, as depicted in Figure 12.

This makes the use of such codes much more attractive.

Fig. 12. Cleopatre Library within Linux/RTAI

site *http://cleopatre.rts-software.org*.

**4.2.2 Overheads and footprints**

Linux extension.

#### **4.1.3 Experiment 3**

Finally, we study the CPU idle time ratio given by the percentage of time during which the processor is not processing any task. This measure quantifies the ability to face a dynamic processing surplus (e.g. the arrival of an aperiodic task). Simulation results for *si* = 2 and *si* = 6 are presented in Figure 11.

Fig. 11. CPU idle time for low and high skips

We note that the CPU idle time ratio under RTO is the highest one compared with all strategies. This ratio declines in a linear fashion according to *Up*. It varies from 55% for *Up* = 90% to 10% for *Up* = 180% and *si* = 2. Note the singular points of the curves *si* = 2 and *si* = 6: when *Up* = 100% idle time ratios are respectively equal to 1 2 = 50% and 1 6 = 16.7% which correspond exactly to the skip factors.

Idle time ratios are identical and positive – e.g. idle time = 10% for *Up* = 90% – when *Up* < 100% under BWP, RLP and RLP/T. They decline in a linear fashion until reaching a zero value for *Up* = 100%.

Results differ for overloaded systems (*Up* > 100%). RLP involves no CPU idle time whatever the skip factors are. We observe that BWP involves a low idle time ratio only under low skip ratios. RLP/T clearly appears as the most efficient strategy, still offering idle time under light overloads. For example, the idle time ratio under RLP/T for *si* = 2 and *Up* = 115% is equal to 9%. RLP/T gives a low and still positive idle time ratio even when the system is highly overloaded.

In summary, RLP/T proves to be the most suitable scheduling strategy to cope with transient overloads while providing the highest Quality of Service.

#### **4.2 Integration into an open-source operating system**

#### **4.2.1 The CLEOPATRE Library**

From 2002 until 2006, we developed a library of free software components within the French National project *CLEOPATRE (Software Open Components on the Shelf for Embedded Real-Time Applications)*. This project aims to provide efficient services to real-time applications (Silly et al., 2007). It enriches real-time Linux variants with enhanced real-time facilities.

14 Will-be-set-by-IN-TECH

Finally, we study the CPU idle time ratio given by the percentage of time during which the processor is not processing any task. This measure quantifies the ability to face a dynamic processing surplus (e.g. the arrival of an aperiodic task). Simulation results for *si* = 2 and

(a) *si* = 2 (b) *si* = 6

We note that the CPU idle time ratio under RTO is the highest one compared with all strategies. This ratio declines in a linear fashion according to *Up*. It varies from 55% for *Up* = 90% to 10% for *Up* = 180% and *si* = 2. Note the singular points of the curves *si* = 2 and

Idle time ratios are identical and positive – e.g. idle time = 10% for *Up* = 90% – when *Up* < 100% under BWP, RLP and RLP/T. They decline in a linear fashion until reaching a zero

Results differ for overloaded systems (*Up* > 100%). RLP involves no CPU idle time whatever the skip factors are. We observe that BWP involves a low idle time ratio only under low skip ratios. RLP/T clearly appears as the most efficient strategy, still offering idle time under light overloads. For example, the idle time ratio under RLP/T for *si* = 2 and *Up* = 115% is equal to 9%. RLP/T gives a low and still positive idle time ratio even when the system is highly

In summary, RLP/T proves to be the most suitable scheduling strategy to cope with transient

From 2002 until 2006, we developed a library of free software components within the French National project *CLEOPATRE (Software Open Components on the Shelf for Embedded Real-Time Applications)*. This project aims to provide efficient services to real-time applications (Silly et

al., 2007). It enriches real-time Linux variants with enhanced real-time facilities.

2 = 50% and 1

6 = 16.7%

*si* = 6: when *Up* = 100% idle time ratios are respectively equal to 1

**4.1.3 Experiment 3**

*si* = 6 are presented in Figure 11.

Fig. 11. CPU idle time for low and high skips

which correspond exactly to the skip factors.

overloads while providing the highest Quality of Service.

**4.2 Integration into an open-source operating system**

value for *Up* = 100%.

**4.2.1 The CLEOPATRE Library**

overloaded.

CLEOPATRE components have been prototyped under *Linux/RTAI (Real-Time Application Interface)* (Racciu & Mantegazza, 2006) and distributed under the LGPL license. The LGPL allows proprietary code to be linked to the GNU C library, glibc. When a program is linked with a library – whether statically or using a shared library – the combination of the two is legally speaking a combined work, a derivative of the original library. Companies do not have to release the source to code that which has been dynamically linked to an LGPLed library. This makes the use of such codes much more attractive.

The CLEOPATRE library offers selectable COTS (Commercial-Off-The-Shelf) components dedicated to dynamic scheduling, aperiodic task servicing, resource control access, fault-tolerance and QoS scheduling. An additional task named *TCL (Task Control Logic)* interfaces all the CLEOPATRE components and has the highest priority. It has been added as a dynamic module in \$*RTAID IR*/*modules*/*TCL*.*o* and interfaces with the legacy RTAI scheduler defined in \$*RTAID IR*/*modules*/*rtai*\_*sched*.*o*, as depicted in Figure 12.

The CLEOPATRE interface is totally independent from the RTAI core layer. It can be directly used with Xenomai – which supports the RTAI API – and easily adapted to any other real-time Linux extension.

Fig. 12. Cleopatre Library within Linux/RTAI

CLEOPATRE applications are highly portable to any new CPU architecture thanks to this OS abstraction layer which makes the library of services generic (Silly et al., 2007). The CLEOPATRE Off-the-Shelf components are optional except for the OS abstraction layer (TCL) and the scheduler. At most one component per shelf can be selected. Since all components of a given shelf have the same programming interface, they become interchangeable. Everything needed to use or extend CLEOPATRE can be downloaded from the project web site *http://cleopatre.rts-software.org*.


**4.1 Simplified structure**

One of the significant shortcomings of inchworm type piezoelectric is the complex structure which brings trouble for the manufacture and control. **Figure 8** shows the structure of the proposed simplified piezoelectric actuator based on the parasitic movement of the flexure mechanism by Li et al. [26]. With the help of the parasitic movement of the flexure mechanism, only two piezoelectric elements are needed. It is mainly composed of the base, the slider, piezostack 1, piezo-stack 2, flexure mechanism 1, flexure mechanism 2, two wedge blocks, four micrometer knobs and eight screws. Piezo-stack 1 (AE0505D16, 5 × 5 × 20 mm, NEC/TOKIN CORPORATION) is inserted into the flexure mechanism 1 through the wedge block to push the linear slider. The assembly process of the piezoelectric stack 2 and the flexure mechanism 2 are the same. The highprecision four-micron knob (M6 from SHSIWI) is utilized to adjust the preloading force between the flexure mechanism and the slider. The slider is a commercial linear guide with high linearity produced by THK. The flexure mechanism is made of aluminum alloy AL7075 manufactured by WEDM. Screws are applied to stably assemble all components on the base. The overall size of the proposed stepping piezoelectric actuator is 100 mm × 60 mm × 18 mm.

**Figure 8.** *Structure of the proposed simplified piezoelectric actuator and motion principle [26].*

Two piezoelectric "legs" are required to alternately drive the slider, and this is why they are sometimes called "walking" type piezoelectric actuators. In addition, for traditional "walking" type piezoelectric actuator, in each piezoelectric "leg", at least two piezoelectric elements are required (one for flexure movement and one for longitudinal movement). The movement principle of the stepping piezoelectric actuator is the "circular movement" of the piezoelectric "legs". In short, each piezoelectric "leg" should achieve two movements in *x* and *y* directions.

In the proposed study by Li et al., the parasitic movement of the flexure mechanism is applied to simplify the entire system. Generally, the piezo-stack could only achieve the one motion in its longitudinal direction. Whereas, as shown in **Figure 8(b)**, with the aid of the asymmetrical flexure mechanism, the piezo-stack will generate an oblique upward force, which causes the motion displacement in both *x* and *y* directions. The parasitic movement *L*x in *x* direction is used to drive the linear movement of the slider. However, only one flexure mechanism cannot achieve walking motion, and at least two flexure mechanisms ("legs") are required. In addition, during the movement, the input square wave voltages *U*1 and *U*2 have the same magnitude but different phases. The experimental results display that the application of the parasitic motion of the flexure mechanism is able to simplify the inchworm type piezoelectric actuator. The stepping motion of the proposed actuator requires only two piezoelectric elements and two input signals. Additionally, performance of the proposed simplified piezoelectric actuator (stepping performance, speed performance, and load performance) has a certain relationship with the input voltage and frequency. Under the conditions of *U* = 100 V and *f* = 1 Hz, the maximum step displacement Δ*L* = 1.75 μm. Under the condition of *U* = 30 V and *f* = 1 Hz, the minimum step displacement Δ*L* = 0.18 μm. When *U* = 100 V, *f* = 20 Hz, the maximum movement speed *V*s = 39.78 μm. This study verifies the feasibility of design and simplification of inchworm type piezoelectric actuators with parasitic motion of flexure mechanisms, and provides a new idea for the research of piezoelectric actuators. Potential applications in optical engineering and cellular operating systems require more work.

#### **4.2 Simplified control**

For most of the inchworm type piezoelectric actuators, three input signals are necessary for one driving unit and two clamping units, which make the control system also complicated. In order to simplify the control system, Gao et al. proposed one novel piezoelectric inchworm actuator which uses a DC motor to drive the permanent magnet for alternate clamping, applies a laser beam sensor to detect the position of the permanent magnet and generates an excitation signal to drive the piezoelectric stack [27]. The actuator only needs a DC signal to drive and can adjust the frequency by changing the motor speed. The movement mechanism of the actuator is emphatically discussed, and the influence of the permanent magnet structure on the clamp is studied. The flexibility matrix method and COMSOL finite element software are used to simulate and analyze the flexure hinge. The driving signal for the piezoelectric stack is generated by self-sensing and automatically adapts to the frequency change, which simplifies the control signal of the inchworm actuator. The use of the magnetic clamping unit solves the serious friction and wear problems of the current clamping method of piezoelectric inchworm actuators. In addition, the driving unit and clamping unit of the proposed piezoelectric inchworm actuator are tested experimentally. The experimental results confirm the feasibility of the proposed scheme and obtained relevant optimized structural parameters.

The overall structure of the proposed actuator, as shown in **Figure 9**, is mainly composed of a sensing unit, a driving unit and a clamping unit. As shown

### *Principle, Design and Future of Inchworm Type Piezoelectric Actuators DOI: http://dx.doi.org/10.5772/intechopen.96411*

in **Figure 9(a)**, the clamping unit is mainly composed of a DC motor, a motor base, a permanent magnet after magnetization (RPM, red), a permanent magnet before magnetization (NRPM, blue), bearings and a bearing housing. As shown in **Figure 9(b)**, the sensing unit includes a cam, a laser beam sensor (OLS) and a bracket. The driving unit includes a flexible hinge mechanism with integrated piezoelectric stack (AE0505D16, NEC/TOKIN CORPORATION), a wedge-shaped adjusting mechanism (built-in a pair of wedges and a pre-tightening bolt) and a slider, as shown in **Figure 9(c)**. The designed slider can slide in the sliding groove of the flexible hinge mechanism. Two clamping modules and cams are fixed at the end of the output shaft of the DC motor, and each clamping module is assembled by a radially polarized permanent magnet RPM and a non-radially polarized permanent magnet NRPM. The piezoelectric stack is preloaded by the wedge-shaped adjusting mechanism and nested in the installation slot of the flexible hinge mechanism. The laser beam sensor is supported by two brackets and generates an excitation signal by detecting the position of the cam. In addition, the support block, the DC motor and the bearing are assembled on the base with eight bolts.

The proposed inchworm actuator by Gao et al. utilizes a DC motor to drive the permanent magnet for rotating to achieve alternate clamping. The actuator does not need to input the driving voltage signal of the piezoelectric stack. It only senses the position of the permanent magnet through the laser beam sensor, and generates an excitation signal to drive the piezoelectric stack to achieve precise linear displacement output. Its working principle is shown in **Figure 10**. Work performance of

**Figure 9.**

*Structure of the actuator by Gao et al.: (a) sensing unit; (b) sensing unit; (c) driving unit [27].*

**Figure 10.**

*Working principle of the inchworm piezoelectric actuator with simplified control system by Gao et al. [27].*

**Figure 11.** *Miniaturized inchworm type actuators: (a) by Risaku et al. [28]; (b) by Mehmet et al. [29].*

the proposed actuator was studied carefully. For the important component of the driving unit, the "Z" type flexure hinge, the flexibility matrix method is used to perform theoretical calculations. The error between the simulation results and the theoretical calculation results is about 2.13%, indicating the accuracy of the calculation; for the magnetic clamping unit, when the clamping distance is 1 mm, the magnetic clamping unit has better clamping capability. The experimental results show that the actuator has a good linear displacement. When *U*e = 150 V and *f* = 40 Hz, its maximum movement speed is 481.43 μm/s, and the maximum load is *m* = 950 g.

#### **4.3 Other directions**

The inchworm type piezoelectric drive device can not only obtain large output stroke, but also ensure high output accuracy and load-carrying capacity, which is favored by many scholars. The research of Inchworm piezoelectric driving device has its own characteristics at home and abroad, which provides a favorable technical basis for the development and application of piezoelectric precision drive technology. Besides the above future directions, the existing inchworm piezoelectric actuator is still in the stage of empirical design and test, lacking of relevant theoretical model guidance, and there are problems of empirical design and repeated attempts. Therefore, it is necessary to establish the dynamic model of the inchworm piezoelectric actuator to guide the design and research of the inchworm piezoelectric drive device. In addition, the miniaturization is always the hot point for piezoelectric actuators which could leads to the real application in many research and industrial fields.

Risaku et al. have developed a large stroke and high precision inchworm actuator [28] (**Figure 11**). With the combination of piezoelectric and electrostatic motion principles, the displacement accuracy of each step reaches tens of nanometers, which can be called ultra-high precision. The displacement accuracy is 59 nm/cycle, but the maximum travel distance is only 600 μm, which needs to be improved.

In order to solve the shortcomings that most inchworm type piezoelectric actuators require larger input voltage, Mehmet et al. took the lead in developing a new type of low voltage, largestroke, and large output inchworm actuator based on the micro-electromechanical systems (MEMS) [29]. It mainly applies the principle of electrostatic motion. Through the amplification of the flexible hinge, it achieves a total displacement of ±18 μm and an output force of ±30 μN at a low voltage of 7 V; a displacement of ±35 μm can be achieved at a voltage of 16 V, ±110 μN output force.

### **5. Conclusion**

The inchworm movement is a high-precision driving method that imitates the movement form of the inchworm in nature to realize the stepping movement of itself or the holding object. Inchworm movement is a kind of stepping movement, *Principle, Design and Future of Inchworm Type Piezoelectric Actuators DOI: http://dx.doi.org/10.5772/intechopen.96411*

which is different from other continuous movement. Its movement can be regarded as a combination of movement and stop in time, but it is also a continuous movement from the perspective of the overall effect of the movement. Inchworm motion can easily achieve large-stroke step-by-step linear motion. Although scholars in various countries have conducted a number of research work on inchworm-type piezoelectric driving devices, most of their research content is linear inchworm driving devices, which involve rotation. There are few reports on the inchworm actuator, and the existing inchworm-type piezoelectric actuator has complex structure control, lacks relevant theoretical model guidance, and has problems of empirical design and repeated attempts. In the future, there is still a lot of work to be solved for the inchworm piezoelectric actuator to promote the real practical use of the inchworm piezoelectric actuator.