Search results for: case pile wave analysis program (CAPWAP)

Authors: Mohammad Imani, JabraeilNasl Seraji, Abolfazl Zakerian

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Background: Reaction time is the amount of time it takes to respond to a stimulus. In fact The time that passes between the introduction of a stimulus and the reaction by the subject to that stimulus. The aim of this interventional study is evaluation of bright light effects on concentration and diffuse attention reaction time, tension, angry, fatigue and alertness among shift workers. There are several incentives that can reduce the reaction time or added. Bright light as one of the environmental factors can reduce reaction time. Material &Method: This cross-sectional descriptive study was conducted in 1391, in 88 subjects (44 Fixed morning worker and 44 shift worker ) In a 24 h time (13-16-19-22-1-4-7-10) in an ordinary light situation after a randomly selected sample size calculation, concentration and diffuse attention test (reaction time) has been done. After intervention and using of bright light (4500lux), again reaction time test was done. After analyzing by ElISA method obtained data were analyzed by statistical software SPSS 19 and using T-test and ANOVA statistical analysis. Results: Between average of reaction time tests in ordinary light exposed to fixed morning workers and bright light exposed to shift worker, with 95% CI, (P>%5) there was no significant relationship. After the intervention and the use of bright light (4500 lux),between average of concentration and diffused attention reaction time tests in ordinary light exposure on the fixed morning workers and bright light exposure shift workers with 95% CI, (P<5%) there was significant relationship. Conclusion: In sometimes of 24 h during ordinary light exposure concentration and diffused attention reaction time has changed in shift workers. After intervention, during bright light (4500lux) exposure as a light shower, focused and diffuse attention reaction time, tension ,angry and fatigue decreased.

Keywords: bright light, reaction time, tension, angry, fatigue, alertness

Procedia PDF Downloads 385

Authors: Abebe Tibebu

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This study investigates the quality of training factors in Ethiopian Technical and Vocational Education and Training (TVET) colleges and their impact on declining enrollment rates. Employing a descriptive survey design, both quantitative and qualitative data were collected from diverse stakeholders, including Grade 12 graduates, current TVET trainees, trainers, college deans, community members, high school directors, teachers, and officials from TVET government agencies. The sample included 20 TVET centers from various Ethiopian regions. Secondary data were obtained from college and government documents, while primary data were gathered through questionnaires, interviews, focus group discussions, and observations. Analysis was conducted using descriptive statistics with SPSS, capturing response frequencies and percentages. The study's findings highlight several key factors affecting TVET enrollment: limited infrastructure capacity, insufficient trainer competency, misaligned curriculum, low-quality training delivery particularly in cooperative training implementation and industry partnership and low success rates on Certification of Competency (CoC) exams. Many TVET institutions lack qualified trainers, adequate machinery, and timely provision of materials for practical skills training. Based on these findings, the study recommends enhanced infrastructure investment, professional development for trainers, curriculum adjustments to better align with industry needs, and standardized assessment practices. Addressing these areas through collaborative efforts with government bodies and industry stakeholders is essential to improving the quality and appeal of Ethiopian TVET programs, ultimately strengthening enrollment and outcomes.

Keywords: TVET, quality factors, enrollment, potentially enrolled

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Authors: Oscar E. Cariceo

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In Chile, social workers´ professional training is developed in the undergraduate level, mainly. Despite the fact that several schools have been launched Master of Social Work programs, the Bachelor in Social Work is the minimum qualification to start a professional career. In the current Chilean higher education system, there exist different financial aid options in order to guarantee equal access to higher education. These policies, which are student loans and scholarships, basically, are applied and distributed by Government agencies. They are linked to academic performance and socio-economic needs, in terms of standardized test scores and social vulnerability criteria. In addition, institutions that enroll students with high scores, also receive direct financial support. In other words, social work students must compete for the resources to pay for college tuitions and fees with other students from different programs and knowledge fields and, as a consequence, they can indirectly enhance schools´ money income. This work aims to describe the reality of social work students to access to financial aid in Chile. The analysis presents the results of the University Selection Test of students, who were accepted in social work undergraduate programs during 2014 related to their qualifications to apply to three main financial aid programs, and their contribution to attracting resources to their schools. In general, data show that social work students participate in a low proportion in the distribution of financial aid, both student loans and scholarships. Few of them reach enough scores to guarantee direct financial resources to their institutions. Therefore, this situation has deep implications on equal access to higher education for vulnerable students and affects equal access to training options for young social workers, due to the highly competitive financial aid system.

Keywords: social work, professional training, higher education, financial aid, equity

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Authors: Tabin Millo, Khoob Chand, Ashok Kumar Jaiswal

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Introduction: Various kinds of violence and offences are related to alcohol consumption by the offenders. The relationship between alcohol and violence is complex. But its study is important to achieve understanding of violence as well as alcohol related behavior. This study was done to know the blood alcohol concentration in people involved in various offences and its demographic pattern. The study was carried out in the forensic toxicology laboratory, department of Forensic Medicine, All India Institute of Medical Sciences, New Delhi, India. Material and methods: The blood samples were collected from the arrested people shortly after the commission of the offence by the emergency medical officers in the emergency department and forwarded to the forensic toxicology laboratory through the investigating officer. The blood samples were collected in EDTA vial with sodium fluoride preservative. The samples were analyzed by using gas chromatography with head space (GC-HS), which is ideal for alcohol estimation. The toxicology reports were given within a week. The data of seven years (2011-17) were analyzed for its alcohol concentration, associated crimes and its demographic pattern. Analysis and conclusion: Total 280 samples were analyzed in the period of 2011-2017. All were males except one female who was a bar dancer. The maximum cases were in the age group of 21-30 years (124 cases). The type of offences involved were road traffic accidents (RTA), assault cases, drunken driving, drinking in public place, drunk on duty, sexual offence, bestiality, eve teasing, fall etc. The maximum cases were of assault (75 cases) followed by RTA (64 cases). The maximum cases were in the alcohol concentration range of 101-150mg% (58 cases) followed by 51-100mg% (52 cases). The maximum blood alcohol level detected was 391.51 mg%, belonging to a security guard found unconscious. This study shows that alcohol consumption is associated with various kinds of violence and offences in society.

Keywords: alcohol, crime, toxicology, violence

Procedia PDF Downloads 143

Authors: Abolfazl Zaraki, Yoshikatsu Hayashi, Harry Thorpe, Vincent Strong, Gisle-Andre Larsen, William Holderbaum

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Thanks to the high maneuverability of the cable-driven hyper-redundant manipulators (HRMs), this class of robots has shown a superior capability in highly confined and unstructured space applications. Although the large number of degrees of freedom (DOF) of HRMs enhances the motion flexibility and the robot’s reachability range, it highly increases the complexity of the kinematic configuration which makes the kinematic control problem very challenging or even impossible to solve. This paper presents our current progress achieved on the development of a kinematic-based leader-follower control system which is designed to control not only the robot’s body posture but also to control the trajectory of the robot’s movement in a semi-autonomous manner (the human operator is retained in the robot’s control loop). To obtain the forward kinematic model, the coordinate frames are established by the classical Denavit–Hartenburg (D-H) convention for a hyper-redundant serial manipulator which has a controlled cables-driven mechanism. To solve the inverse kinematics of the robot, unlike the conventional methods, a leader-follower mechanism, based on the sequential inverse kinematic, is followed. Using this mechanism, the inverse kinematic problem is solved for all sequential joints starting from the head joint to the base joint of the robot. To verify the kinematic design and simulate the robot motion, the MATLAB robotic toolbox is used. The simulation result demonstrated the promising capability of the proposed leader-follower control system in controlling the robot motion and trajectory in our confined space application.

Keywords: hyper-redundant robots, kinematic analysis, semi-autonomous control, serial manipulators

Procedia PDF Downloads 157

Authors: Arfan Ali, Muhammad Shahzad Iqbal, Idrees Ahmad Nasir

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Potato (Solanum tuberosum L.) is ranked among the top leading staple foods in the world. Salinity adversely affects potato crop yield and quality. Therefore, increased level of salt tolerance is a key factor to ensure high yield. The present study focused on the Agrobacterium-mediated transformation of Atriplex canescens betaine aldehyde dehydrogenase (BADH) gene, using single, double and triple CAMV35s promoter to improve salt tolerance in potato. Detection of seven potato lines harboring BADH gene, followed by identification of T-DNA insertions, determination of transgenes copies no through Southern Hybridization and quantification of BADH protein through Enzyme Linked Immunosorbent Assay were considered in this study. The results clearly depict that the salt tolerance of potato was found to be promoter-dependent, as the potato transgenic lines with triple promoter showed 4.4 times more glycine betaine production which consequently leads towards high resistance to salt stress as compared to transgenic potato lines with single and double promoters having least production of glycine betaine. Moreover, triple promoter transgenic potato lines have also shown lower levels of H2O2, malondialdehyde (MDA), relative electrical conductivity, high proline and chlorophyll content as compared other two lines having a single and double promoter. Insilco analysis also confirmed that Atriplex canescens BADH has the tendency to interact with sodium ions and water molecules. Taken together these facts it can be concluded that over-expression of BADH under triple CAMV35s promoter with more glycine betaine, chlorophyll & MDA contents, high relative quantities of other metabolites results in an enhanced level of salt tolerance in potato.

Keywords: Atriplex canescens, BADH, CAMV35s promotor, potato, Solanum tubersum

Procedia PDF Downloads 277

Authors: Karimeh Alnuaimi, Manal Kassab, Reem Ali, Khitam Mohammad, Kholoud Shattnawi

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Aim: To compare pregnancy outcomes of Syrian refugee women and Jordanian women. Background and introduction: The current conflict in Syria continues to displace thousands to neighboring countries, including Jordan. Pregnant refugee women are therefore facing many difficulties are known to increase the prevalence of poor reproductive health outcomes and antenatal complications. However, there is very little awareness of whether Syrian refugee women have different risks of pregnancy outcomes than Jordanian women. Methods: Using a retrospective cohort design, we examined pregnancy outcomes for Syrian refugee (N = 616) and Jordanian women (N = 644) giving birth at two governmental Hospitals in the north of Jordan, between January 1, 2014, and December 31, 2014. A checklist of 13 variables was utilized. The primary outcome measures were delivery by Caesarean section, maternal complications, low birth weight (< 2500 g), Apgar score and preterm delivery (< 37 weeks' gestational age). Results: Statistical analysis revealed that refugee mothers had a significant increase in the rate of cesarean section and the higher rate of anemia, a lower neonates’ weight, and Apgar scores when compared to their Jordanian counterparts. Discussion and Conclusion: Results were congruent with findings from other studies in the region and worldwide. Minimizing inequalities in pregnancy outcomes between Syrian refugees and Jordan women is a healthcare priority. Implications for nursing and health policy: The findings could guide the planning and development of health policies in Jordan that would help to alleviate the situation regarding refugee populations. The action is required by the policy makers, specifically targeting public and primary health care services, to address the problem of adequately meeting the need for antenatal care of this vulnerable population.

Keywords: pregnancy, Syrian refugee, Jordanian women, comparative study

Procedia PDF Downloads 361

Authors: Tomas Premoli, Sareh Rowlands

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In this study, we investigate the impact of various convolutional neural network (CNN) architectures on the accuracy of diagnosing Alzheimer’s disease (AD) using patient MRI scans. Alzheimer’s disease is a debilitating neurodegenerative disorder that affects millions worldwide. Early, accurate, and non-invasive diagnostic methods are required for providing optimal care and symptom management. Deep learning techniques, particularly CNNs, have shown great promise in enhancing this diagnostic process. We aim to contribute to the ongoing research in this field by comparing the effectiveness of different CNN architectures and providing insights for future studies. Our methodology involved preprocessing MRI data, implementing multiple CNN architectures, and evaluating the performance of each model. We employed intensity normalization, linear registration, and skull stripping for our preprocessing. The selected architectures included VGG, ResNet, and DenseNet models, all implemented using the Keras library. We employed transfer learning and trained models from scratch to compare their effectiveness. Our findings demonstrated significant differences in performance among the tested architectures, with DenseNet201 achieving the highest accuracy of 86.4%. Transfer learning proved to be helpful in improving model performance. We also identified potential areas for future research, such as experimenting with other architectures, optimizing hyperparameters, and employing fine-tuning strategies. By providing a comprehensive analysis of the selected CNN architectures, we offer a solid foundation for future research in Alzheimer’s disease diagnosis using deep learning techniques. Our study highlights the potential of CNNs as a valuable diagnostic tool and emphasizes the importance of ongoing research to develop more accurate and effective models.

Keywords: Alzheimer’s disease, convolutional neural networks, deep learning, medical imaging, MRI

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Authors: In-Hwan Baek

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Valsartan is a potent and highly selective antagonist of the angiotensin II type 1 receptor, and is widely used for the treatment of hypertension. The aim of this study was to investigate the pharmacokinetic properties of the valsartan in dogs following oral administration of a single dose using quantitative modeling approaches. Forty beagle dogs were randomly divided into two group. Group A (n=20) was administered a single oral dose of valsartan 80 mg (Diovan® 80 mg), and group B (n=20) was administered a single oral dose of valsartan 160 mg (Diovan® 160 mg) in the morning after an overnight fast. Blood samples were collected into heparinized tubes before and at 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, 12 and 24 h following oral administration. The plasma concentrations of the valsartan were determined using LC-MS/MS. Non-compartmental pharmacokinetic analyses were performed using WinNonlin Standard Edition software, and modeling approaches were performed using maximum-likelihood estimation via the expectation maximization (MLEM) algorithm with sampling using ADAPT 5 software. After a single dose of valsartan 80 mg, the mean value of maximum concentration (Cmax) was 2.68 ± 1.17 μg/mL at 1.83 ± 1.27 h. The area under the plasma concentration-versus-time curve from time zero to the last measurable concentration (AUC24h) value was 13.21 ± 6.88 μg·h/mL. After dosing with valsartan 160 mg, the mean Cmax was 4.13 ± 1.49 μg/mL at 1.80 ± 1.53 h, the AUC24h was 26.02 ± 12.07 μg·h/mL. The Cmax and AUC values increased in proportion to the increment in valsartan dose, while the pharmacokinetic parameters of elimination rate constant, half-life, apparent of total clearance, and apparent of volume of distribution were not significantly different between the doses. Valsartan pharmacokinetic analysis fits a one-compartment model with first-order absorption and elimination following a single dose of valsartan 80 mg and 160 mg. In addition, high inter-individual variability was identified in the absorption rate constant. In conclusion, valsartan displays the dose-dependent pharmacokinetics in dogs, and Subsequent quantitative modeling approaches provided detailed pharmacokinetic information of valsartan. The current findings provide useful information in dogs that will aid future development of improved formulations or fixed-dose combinations.

Keywords: dose-dependent, modeling, pharmacokinetics, valsartan

Procedia PDF Downloads 297

Authors: Puthsodary Tat

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Democracy has been categorially accepted and used as foreign and domestic policy agendas for the hope of peace, economic growth and prosperity for more than 25 years in Cambodia. However, the country is now in the grip of dictatorship, human rights violations, and prospective economic sanctions. This paper examines different perceptions and experiences of democratic assistance. In this study, the author employs discourse theory, idealism and realism as a theory-based methodology for debating and assessing the implications of democratization. Discourse theory is used to establish a platform for understanding discursive formations, body of knowledge and the games of truth of democracy. Idealist approaches give rational arguments for adopting key tenets that work well on the ground. In contrast, realism allows for some sweeping critiques of utopian ideal and offers particular views on why Western hegemonic missions do not work well. From idealist views, the research finds that Cambodian people still believe that democracy is a prima facie universality for peace, growth and prosperity. From realism, democratization is on the brink of death in three reasons. Firstly, there are tensions between Western and local discourses about democratic values and norms. Secondly, democratic tenets have been undermined by the ruling party-controlled courts, corruption, structural oppression and political patronage-based institutions. The third pitfall is partly associated with foreign aid dependency and geopolitical power struggles in the region. Finally, the study offers a precise mosaic of democratic principles that may be used to avoid a future geopolitical and economic crisis.

Keywords: corruption, democracy, democratic principles, discourse theory, discursive formations, foreign aid dependency, games of truth, geopolitical and economic crisis, geopolitical power struggle, hegemonic mission, idealism, realism, utopian ideal

Procedia PDF Downloads 200

Authors: Gadia Duhita, Noorhana, Tjhin Wiguna

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Background: ADHD is the most common behavioural disorder in Indonesia. A stimulant, specifically methylphenidate, has been the first drug of choice for an ADHD treatment more than half a century. During the last decade, non-stimulant therapy (atomoxetine) for ADHD treatment has been developing. Growing evidence of its efficacy and the difference in its side effects profile to stimulant therapy have made methylphenidate’s position as a first line therapy for ADHD in need of re-evaluation. Both methylphenidate and atomoxetine have proven themselves against placebos in reducing core symptoms of ADHD. More recent studies directly compare the efficacy of methylphenidate and atomoxetine. Objective: The objective of this paper is to find out if either methylphenidate or atomoxetine is superior to another. This paper will assess the validity, importance, and applicability of current available evidence which compare the effectivity, efficacy, and safety of methylphenidate to atomoxetine for treatment in children and adolescents with ADHD. Method: The articles were searched for through the PubMed and Cochrane databases with “attention deficit/hyperactivity disorder OR adhd”, “methylphenidate”, and “atomoxetine” as the search keywords. Two articles which were relevant and eligible were chosen by using inclusion and exclusion criterias to be critically appraised. Result: The study by Hazel et al. showed that the efficacy of methylphenidate and atomoxetine are comparable for treatment in child and adolescent ADHD. The result shows 53.6% (95% CI 48.5%-58.4%) of the patient responded to the treatment by atomoxetine and 54.4% (95% CI 47.6%-61.1%) patients responded to methylphenidate, with the difference in proportion of–0.9% (95% CI –9.2%-7.5%). The other study by Hanwella et al. also showed that the efficacy of atomoxetine was not inferior to metilphenidate (SMD = 0.09, 95% CI –0.08-0.26) (Z = 1.06, p = 0.29). However, the sub-group analysis showed that OROS methylphenidate is more effective compared to atomoxetine (SMD = 0.32, 95% CI 0.12-0.53) (Z = 3.05, p < 0.02). Conclusion: The efficacy of methylphenidate and atomoxetine in reducing symptoms of ADHD is comparable. None is proven inferior to another. The choice of pharmacological tratment children and adolescents with ADHD should be made based on contraindication and the side effects profile of each drug.

Keywords: attention deficit/hyperactivity disorder, ADHD, atomoxetine, methylphenidate

Procedia PDF Downloads 475

Authors: Bremmy Laksono, Riksa Parikrama, Nur A. Rosyada, Willyanti Soewondo, Dadang S. H. Effendi, Eriska Rianti, Arlette S. Setiawan, Ine Sasmita, Risti S. Primanti, Erna Kurnikasari, Yunia Sribudiani

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Down syndrome (DS) is a chromosomal abnormality characterised by complete 21 chromosome trisomy (classical or non-disjunction), or partial 21 chromosome trisomy (mosaicism), or chromosome rearrangement involving chromosome 21 (translocation). This study was carried out to describe the frequency of DS patients in a research institution in the city of Bandung, Indonesia. This descriptive study also provides a picture of the residential location and surrounding area of their dwellings. This study involved people with DS in various age whose chromosome were evaluated by conventional karyotyping method and FISH. Data were collected from 60 patients with DS from a total 150 patients during the period of September 2015 to August 2016 who were referred to Cell Culture and Cytogenetics Laboratory, Faculty of Medicine Universitas Padjadjaran, Indonesia. Results showed that the most common type of DS was non-disjunction (93%), followed by mosaicism (5%), no patient with translocation DS (0%), and a very rare type of tetrasomy 21 (2%). There were 39 males (65%) and 21 females (35%) of DS patient. Most of them live in suburban area beyond Bandung city (55%) while the rest live inside urban area of Bandung city (45%). They live mostly in dense area of greater Bandung area (65%) and only a few live in mid-density area (25%) and the least live in sparse populated area (10%). Their houses are mostly located in residential estate area (55%), nearby industrial area (37%), and around agricultural area (8%). Based on the study, it could be concluded that non-disjunction DS is the most common type. DS patients referred to the laboratory mostly came from dense residential zone in suburban area outside Bandung city. The low number of DS patients referred to the laboratory for chromosome analysis was the highlight to improve health service for people with genetic disorder. This study offered several information regarding area of DS patients’ residence and the condition of neighbourhood in Bandung city where they live as well.

Keywords: chromosome, descriptive, Down syndrome, prevalence

Procedia PDF Downloads 280

Authors: Anurag Mishra, Prabhat Kumar Singh, Anurag Ohri, Shishir Gaur

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Streams and rivulets are crucial in maintaining river networks and their hydrology, influencing downstream ecosystems, and connecting different watersheds of urban and rural areas. The river Assi, an urban river, once a lifeline for the locals, has degraded over time. Evidence, such as the presence of paleochannels and patterns of water bodies and settlements, suggests that the river Assi was initially an alluvial stream or rivulet that originated near Rishi Durvasha Ashram near Prayagraj, flowing approximately 120 km before joining the river Ganga at Assi ghat in Varanasi. Presently, a major challenge is that nearly 90% of its original channel has been silted and disappeared, with only the last 8 km retaining some semblance of a river. It is possible that initially, the river Assi branched off from the river Ganga and functioned as a Yazoo stream. In this study, paleochannels of the river Assi were identified using Landsat 5 imageries and SRTM DEM. The study employed the Normalized Difference Vegetation Seasonality Index (NDVSI) and Principal Component Analysis (PCA) of the Normalized Difference Vegetation Index (NDVI) to detect these paleochannels. The average elevation of the sub-basin at the Durvasha Rishi Ashram of river Assi is 96 meters, while it reduces to 80 meters near its confluence with the Ganga in Varanasi, resulting in a 16-meter elevation drop along its course. There are 81 subbasins covering an area of 83,241 square kilometers. It is possible that due to the increased resistance in the flow of river Assi near urban areas of Varanasi, a new channel, Morwa, has originated at an elevation of 87 meters, meeting river Varuna at an elevation of 79 meters. The difference in elevation is 8 meters. Furthermore, the study explored the possibility of restoring the paleochannel of the river Assi and nearby ponds and water bodies to improve the river's base flow and overall hydrological conditions.

Keywords: River Assi, small river restoration, paleochannel identification, remote sensing, GIS

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Authors: Saba Didarataee, Abbas Ali Khodadadi, Yadollah Mortazavi, Fatemeh Mousavi

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Photocatalytic water splitting is one of the most attractive alternative methods for hydrogen evolution. A variety of nanoparticle engineering techniques were introduced to improve the activity of semiconductor photocatalysts. Among these methods, heterojunction formation is an appealing method due to its ability to effectively preventing electron-hole recombination and improving photocatalytic activity. Reaching an optimal ratio of the two target semiconductors for the formation of heterojunctions is still an open question. Considering environmental issues as well as the cost and availability, ZnS and ZnO are frequently studied as potential choices. In this study, first, the ZnS nanoparticle was synthesized in a hydrothermal process; the formation of ZnS nanorods with a diameter of 14-30 nm was confirmed by field emission scanning electron microscope (FESEM). Then two different methods, partial oxidation and chemical precipitation were employed to construct ZnS/ZnO core-shell heterojunction. X-ray diffraction (XRD), BET, and diffuse reflectance spectroscopy (DRS) analysis were carried out to determine crystallite phase, surface area, and bandgap of photocatalysts. Furthermore, the temperature of oxidation was specified by a temperature programmed oxidation (TPO) and was fixed at 510℃, at which mild oxidation occurred. The bandgap was calculated by the Kubelka-Munk method and decreased by increasing oxide content from 3.53 (pure ZnS) to 3.18 (pure ZnO). The optimal samples were determined by testing the photocatalytic activity of hydrogen evolution in a quartz photoreactor with side irradiation of UVC lamps with a wavelength of 254 nm. In both procedures, it was observed that the photocatalytic activity of the ZnS/ZnO composite was sensibly higher than the pure ZnS and ZnO, which is attributed to forming a type-II heterostructure. The best ratio of oxide to sulfide was 0.24 and 0.37 in partial oxidation and chemical precipitation, respectively. The highest hydrogen evolution was 1081 µmol/gr.h, gained from partial oxidizing of ZnS nanoparticles at 510℃ for 30 minutes.

Keywords: heterostructure, hydrogen, partial oxidation, photocatalyst, water splitting, ZnS

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Authors: Katarzyna Wal, Wojciech Stawiński, Piotr Rutkowski

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The scientific community is paying more and more attention to the problem of air pollution. Carbon dioxide is classified as one of the most harmful gases. Its emissions are generated during fossil fuel burning, waste management, and combustion and are responsible for global warming. Clay minerals constitute a group of promising materials for the role of adsorbents. They are composed of two types of phyllosilicate sheets: tetrahedral and octahedral, which form 1:1 or 2:1 structures. Vermiculite is one of their best-known representative, which can be used as an adsorbent from water and gaseous phase. The aim of the presented work was carbon dioxide adsorption on vermiculite. Acid-activated samples (W_NO3_x) were prepared by acid treatment with different concentrations of nitric acid (1, 2, 3, 4 mol L⁻¹). Vermiculite was subjected to modification in order to increase its porosity and adsorption properties. The prepared adsorbents were characterized using the BET-specific surface area analysis, thermogravimetry (TG), attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). Applied modifications significantly increase the specific surface area from 78,21 m² g⁻¹ for the unmodified sample (W_REF) to 536 m² g-1 for W_NO3_4. Obtained results showed that acid treatment tunes the material’s functional properties by increasing the contact surface and generating more active sites in its structure. The adsorption performance in terms carbon dioxide adsorption capacities follows the order of W_REF (25.91 mg g⁻¹) < W_NO3_1 (38.54 mg g⁻¹) < W_NO3_2 (44.03 mg g⁻¹) W_NO3_4 (67.51 mg g⁻¹) < W_NO3_3 (70.48 mg g⁻¹). Acid activation significantly improved the carbon dioxide adsorption properties of modified samples compared to raw material. These results demonstrate that vermiculite-based samples have the potential to be used as effective CO₂ adsorbents. Furthermore, acid treatment is a promising technique for improving the adsorption properties of clay minerals.

Keywords: adsorption, adsorbent, clay minerals, air pollution, environment

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Authors: Hassan Beigi Rizi, Harold Auradou, Lamine Hattali

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Various industries, including civil engineering, automotive, aerospace, and biomedical fields, are currently seeking novel and innovative high-performance lightweight materials to reduce energy consumption. Inspired by the structure of Euplectella Aspergillum Glass Sponges (EA-sponge), 2D unit cells were created and fabricated using a Fused Filament Fabrication (FFF) process with Polylactic acid (PLA) filaments. The stiffness and strength of bio-inspired EA-sponge lattices were investigated both experimentally and numerically under uniaxial tensile loading and are compared to three standard square lattices with diagonal struts (Designs B and C) and non-diagonal struts (Design D) reinforcements. The aim is to establish predictive scaling laws models and examine the deformation mechanisms involved. The results indicated that for the EA-sponge structure, the relative moduli and yield strength scaled linearly with relative density, suggesting that the deformation mechanism is stretching-dominated. The Finite element analysis (FEA), with periodic boundary conditions for volumetric homogenization, confirms these trends and goes beyond the experimental limits imposed by the FFF printing process. Therefore, the stretching-dominated behavior, investigated from 0.1 to 0.5 relative density, demonstrate that the study of EA-sponge structure can be exploited for the realization of square lattice topologies that are stiff and strong and have attractive potential for lightweight structural applications. However, the FFF process introduces an accuracy limitation, with approximately 10% error, making it challenging to print structures with a relative density below 0.2. Future work could focus on exploring the impact of different printing materials on the performance of EA-sponge structures.

Keywords: bio-inspiration, lattice structures, fused filament fabrication, scaling laws

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Authors: Anna Strakowska, Marian Zaborski

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This abstract focuses an overview of the methods used to create self-healing silicone composites. It has been shown how incorporating of polyhedral oligomeric silsesquioxanes (POSS) molecules with acid and basic groups to silicone rubber affects the barrier properties, mechanical properties in room and reduced temperature or the influence on relaxation rates of the methylvinylsilicone rubber vulcanizates. Moreover, the presence of silsesquioxanes, their content and the way of composites preparing affect the amount of ionic bonds, as indicated by dynamic - mechanical thermal analysis (DMTA) as well as measurements of equilibrium swelling in toluene. The aim of this work was to study the influence of concentration and different functional groups types selected silsesquioxanes compounds on self-healing effect of silicone rubber and obtain elastomers with good barrier and mechanical properties. Composites based on the methylvinylsilicone rubber with fumed silica as the fillers were manufactured and studied. To obtain self-healing effect various silsesquioxanes with amino and acid groups were used. Every tested sample demonstrated the ability to the self-treatment. The most significant effect was observed for system containing amic-acid isobytyl POSS/ aminopropylisobutyl POSS. Composite with this silsesquioxanes was exhibited the best improvement of gas permeability after heal. Moreover, the addition of POSS with acid and basic groups clearly affects the mechanical properties of the vulcanizates. The most significant effect was observed for the composite material consisting of amic-acid isobytyl POSS / aminoethylaminopropylisobutyl POSS, which tensile strength was even greater than the reference vulcanizate with fumed silica. The development of autonomous self-healing materials could have an enormous influence on all industry branches from motorization to power industry. Self-repairing materials would have a massive impact on lengthening product lifetimes, increasing safety, and lowering product costs by reducing maintenance requirements.

Keywords: barrier properties, mechanical properties, POSS, self-healing composites

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Authors: Abdel-Monem Sayed Mohamed

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Egypt rapidly growing development is accompanied by increasing levels of standard living particular in its urban areas. However, there is a limited experience in quantifying the sources of risk management in Egypt and in designing efficient strategies to keep away serious impacts of earthquakes. From the historical point of view and recent instrumental records, there are some seismo-active regions in Egypt, where some significant earthquakes had occurred in different places. The special tectonic features in Egypt: Aswan, Greater Cairo, Red Sea and Sinai Peninsula regions are the territories of a high seismic risk, which have to be monitored by up-to date technologies. The investigations of the seismic events and interpretations led to evaluate the seismic hazard for disaster prevention and for the safety of the dense populated regions and the vital national projects as the High Dam. In addition to the monitoring of the recent crustal movements, the most powerful technique of satellite geodesy GPS are used where geodetic networks are covering such seismo-active regions. The results from the data sets are compared and combined in order to determine the main characteristics of the deformation and hazard estimation for specified regions. The final compiled output from the seismological and geodetic analysis threw lights upon the geodynamical regime of these seismo-active regions and put Aswan and Greater Cairo under the lowest class according to horizontal crustal strains classifications. This work will serve a basis for the development of so-called catastrophic models and can be further used for catastrophic risk management. Also, this work is trying to evaluate risk of large catastrophic losses within the important regions including the High Dam, strategic buildings and archeological sites. Studies on possible scenarios of earthquakes and losses are a critical issue for decision making in insurance as a part of mitigation measures.

Keywords: b-value, Gumbel distribution, seismic and GPS data, strain parameters

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Authors: B. L. Gadiga

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This study assesses the major ecological zones in Nigeria with the view to understanding the spatial pattern of vegetation zones and the implications on conservation within the period of sixteen (16) years. Satellite images used for this study were acquired from the SPOT-VEGETATION between 1998 and 2013. The annual NDVI images selected for this study were derived from SPOT-4 sensor and were acquired within the same season (November) in order to reduce differences in spectral reflectance due to seasonal variations. The images were sliced into five classes based on literatures and knowledge of the area (i.e. <0.16 Non-Vegetated areas; 0.16-0.22 Sahel Savannah; 0.22-0.40 Sudan Savannah, 0.40-0.47 Guinea Savannah and >0.47 Forest Zone). Classification of the 1998 and 2013 images into forested and non forested areas showed that forested area decrease from 511,691 km² in 1998 to 478,360 km² in 2013. Differencing change detection method was performed on 1998 and 2013 NDVI images to identify areas of ecological concern. The result shows that areas undergoing vegetation degradation covers an area of 73,062 km² while areas witnessing some form restoration cover an area of 86,315 km². The result also shows that there is a weak correlation between rainfall and the vegetation zones. The non-vegetated areas have a correlation coefficient (r) of 0.0088, Sahel Savannah belt 0.1988, Sudan Savannah belt -0.3343, Guinea Savannah belt 0.0328 and Forest belt 0.2635. The low correlation can be associated with the encroachment of the Sudan Savannah belt into the forest belt of South-eastern part of the country as revealed by the image analysis. The degradation of the forest vegetation is therefore responsible for the serious erosion problems witnessed in the South-east. The study recommends constant monitoring of vegetation and strict enforcement of environmental laws in the country.

Keywords: vegetation, NDVI, SPOT-vegetation, ecology, degradation

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Authors: Modreck Gomo

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The evolution of groundwater chemistry and its quality is largely controlled by hydrogeochemical processes and their understanding is therefore important for groundwater quality assessments and protection of the water resources. A study was conducted in Bloemfontein town of South Africa to assess and compare the groundwater chemistry and quality characteristics in an alluvial aquifer and single-plane fractured-rock aquifers. 9 groundwater samples were collected from monitoring boreholes drilled into the two aquifer systems during a once-off sampling exercise. Samples were collected through low-flow purging technique and analysed for major ions and trace elements. In order to describe the hydrochemical facies and identify dominant hydrogeochemical processes, the groundwater chemistry data are interpreted using stiff diagrams and principal component analysis (PCA), as complimentary tools. The fitness of the groundwater quality for domestic and irrigation uses is also assessed. Results show that the alluvial aquifer is characterised by a Na-HCO₃ hydrochemical facie while fractured-rock aquifer has a Ca-HCO₃ facie. The groundwater in both aquifers originally evolved from the dissolution of calcite rocks that are common on land surface environments. However the groundwater in the alluvial aquifer further goes through another evolution as driven by cation exchange process in which Na in the sediments exchanges with Ca²⁺ in the Ca-HCO₃ hydrochemical type to result in the Na-HCO₃ hydrochemical type. Despite the difference in the hydrogeochemical processes between the alluvial aquifer and single-plane fractured-rock aquifer, this did not influence the groundwater quality. The groundwater in the two aquifers is very hard as influenced by the elevated magnesium and calcium ions that evolve from dissolution of carbonate minerals which typically occurs in surface environments. Based on total dissolved levels (600-900 mg/L), groundwater quality of the two aquifer systems is classified to be of fair quality. The negative potential impacts of the groundwater quality for domestic uses are highlighted.

Keywords: alluvial aquifer, fractured-rock aquifer, groundwater quality, hydrogeochemical processes

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Authors: M. Abdullahi, S. Sadiku, Bashar S. Mohammed, J. I. Aguwa

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The properties of hollow sandcrete blocks produced in Minna, Nigeria are presented. Sandcrete block is made of cement, water and sand bound together in certain mix proportions. For the purpose of this work, fifty (50) commercial sandcrete block industries were visited in Minna, Nigeria to obtain block samples and aggregates used for the manufacture, and to also take inventory of the mix composition and the production process. Sieve analysis tests were conduction on the soil sample from various block industries to ascertain their quality to be used for block making. The mix ratios were also investigated. Five (5) nine inches (9’’ or 225mm) blocks were obtained from each block industry and tested for dimensional compliance and compressive strength. The result of test shows that the grading of the sand falls within the limit required by BS 882: 1990. The sand particles generally satisfy the grading requirement of overall grading and also fall in at least one of the classification of coarse grading, medium grading or fine grading. This clearly indicates that the quality of the aggregates used for the production of sandcrete blocks in Minna, Nigeria are of good quality in terms of grading and workable mix can easily be achieved to obtain high quality product. Physical examinations of the block sizes show slight deviation from the standard requirement in NIS 87:2000. Compressive strength of hollow sandcrete blocks in range of 0.12 N/mm2 to 0.54 N/mm2 was obtained which is below the recommendable value of 3.45 N/mm2 for load bearing hollow sandcrete blocks. This indicates that these blocks are below the standard for load-bearing sandcrete blocks and cannot be used as load bearing walling units. The mix composition also indicated low cement content resulting in low compressive strength. Most of the commercial block industries visited do not take curing very serious. Water were only sprinkled ones or twice before the blocks were stacked and made readily available for sale. It is recommended that a mix ratio of 1:4 to 1:6 should be used for the production of sandcrete blocks and proper curing practice should be adhered to. Blocks should also be cured for 14 days before making them available for consumers.

Keywords: compressive strength, dimensions, mix proportions, sandcrete blocks

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Authors: Melkamu Tadesse Getachew

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Intelligent control systems have revolutionized biomedical engineering, advancing research and enhancing medical practice. This review paper examines the impact of intelligent control on various aspects of biomedical engineering. It analyzes how these systems enhance precision and accuracy in biomedical instrumentation, improving diagnostics, monitoring, and treatment. Integration challenges are addressed, and potential solutions are proposed. The paper also investigates the optimization of drug delivery systems through intelligent control. It explores how intelligent systems contribute to precise dosing, targeted drug release, and personalized medicine. Challenges related to controlled drug release and patient variability are discussed, along with potential avenues for overcoming them. The comparison of algorithms used in intelligent control systems in biomedical control is also reviewed. The implications of intelligent control in computational and systems biology are explored, showcasing how these systems enable enhanced analysis and prediction of complex biological processes. Challenges such as interpretability, human-machine interaction, and machine reliability are examined, along with potential solutions. Intelligent control in biomedical engineering also plays a crucial role in risk management during surgical operations. This section demonstrates how intelligent systems improve patient safety and surgical outcomes when integrated into surgical robots, augmented reality, and preoperative planning. The challenges associated with these implementations and potential solutions are discussed in detail. In summary, this review paper comprehensively explores the widespread impact of intelligent control on biomedical engineering, showing the future of human health issues promising. It discusses application areas, challenges, and potential solutions, highlighting the transformative potential of these systems in advancing research and improving medical practice.

Keywords: Intelligent control systems, biomedical instrumentation, drug delivery systems, robotic surgical instruments, Computational monitoring and modeling

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Authors: A. Abdulla Khairi Mohamed, Mohamed Gamal Abdelmonem, Gehan Selim

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Walkability in civic and public spaces in Libyan cities is challenging due to the lack of accessibility design, informal merging into car traffic, and the general absence of adequate urban and space planning. The lack of accessible and pedestrian-friendly public spaces in Libyan cities has emerged as a major concern for the government if it is to develop smart and sustainable spaces for the 21st century. A walkable urban space has become a driver for urban development and redistribution of land use to ensure pedestrian and walkable routes between sites of living and workplaces. The characteristics of urban open space in the city centre play a main role in attracting people to walk when attending their daily needs, recreation and daily sports. There is significant gap in the understanding of perceptions, feasibility and capabilities of Libyan urban space to accommodate enhance or support the smart design of a walkable pedestrian-friendly environment that is safe and accessible to everyone. The paper aims to undertake observations of walkability and walkable space in the city of Tripoli as a benchmark for Libyan cities; assess the validity and consistency of the seven principal aspects of smart design, safety, accessibility and 51 factors that affect the walkability in open urban space in Tripoli, through the analysis of 10 local urban spaces experts (town planner, architect, transport engineer and urban designer); and explore user groups’ perceptions of accessibility in walkable spaces in Libyan cities through questionnaires. The study sampled 200 respondents in 2015-16. The results of this study are useful for urban planning, to classify the walkable urban space elements which affect to improve the level of walkability in the Libyan cities and create sustainable and liveable urban spaces.

Keywords: walkability, sustainability, liveability, accessibility

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Authors: Monica Dantas

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At what socio-economic costs can the food industry offer products at low prices? This research seeks to understand and to explore how we attribute competence and meaning, what enables the outcomes of agriculture and what institutions provides validation regarding food production. This study objective is to explain and interpret conditions of the present state of agriculture in Brazil centring on two distinct segments, agribusiness and family farming, as the Brazilian, rapidly changing political environment unfolds. The approach is grounded in multidisciplinary literature drawing from the politics of development, the sociology of food, the sustainability framework and the conceptual differences between agribusiness and family farming regarding the innate purpose of the two segments. In addition, a quantitative portion of the research includes secondary data analysis from statistical measurements, economic indicators, federal budget information, and census data to compare the two segments, conveying a general snapshot of the conditions investigated. The results raised questions about the perceived image of the success of agribusiness, against some contradicting economic checks and balances. Analyzing how public funds are invested in agriculture shed light on what can enable or undermine the development of food systems in Brazil. It also revealed how politics, ideology, and corporations might influence the Brazilian Federal. In the 2000-2018 observed timeline of annual federal spending on agriculture in Brazil, there is variation in the amount invested in family farming that seems to 'coincide' with the ideological direction of the federal government in power. It was also observed that significant changes in the institutional framework and financial support either promoted or purposely undermined family farming importance using public institutions to validate support for agribusiness.

Keywords: food politics, sustainability, family farming, food system, public budget

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Authors: Karl Kingsley

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Many mechanisms are involved in the control of cellular differentiation and growth, which are often dysregulated in many cancers. Many distinct pathways are involved in these mechanisms of control, including deoxyribonuclease (DNA) methyltransferase and histone deacetylase (HDAC) activation that controls both genetic and epigenetic modifications and micro ribonucleic acid (RNA) expression. Less is known about the expression of DNA methyltransferase (DNMT) and HDAC in oral cancers and the effect on microRNA expression. The primary objective of this study was to evaluate the expression of DNMT and HDAC family members in oral cancer and the concomitant expression of cancer-associated microRNAs. Using commercially available oral cancers, including squamous cell carcinoma (SCC)-4, SCC-9, SCC-15, and SCC-25, RNA was extracted and screened for DNMT, HDAC, and microRNA expression using highly-specific primers and quantitative polymerase chain reaction (qPCR). These data revealed low or absent expression of DNMT-1, which is associated with cellular differentiation but increased expression of DNMT-3a and DNMT-3b in all SCC cell lines compared with normal non-cancerous cell controls. In addition, no expression of HDAC1 and HDAC2 expression was found among the normal, non-cancerous cells but was highly expressed in each of the SCC cell lines examined. Differential expression of oncogenic and cancer-associated microRNAs was also observed among the SCC cell lines, including miR-21, miR-133, miR-149, miR-155, miR-365, and miR-720. These findings also appeared to vary according to observed growth rates among these cells. These data may be the first to demonstrate the expression and association between HDAC and DNMT3 family members among oral cancers. In addition, the differential expression of these epigenetic modifiers may be associated with the expression of specific microRNAs in these cancers, which have not previously been observed to the best of the author's knowledge. In addition, some associations and relationships may exist between the expression of these biomarkers and the rates of growth and proliferation, which may suggest that these expression patterns might represent potentially useful biomarkers to determine tumor aggressiveness and other phenotypic behaviors among oral cancers.

Keywords: oral cancer, DNA methyltransferase, histone deacetylase, microRNA

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Authors: Jamal Alasiri, Naif Hakeem, Saoud Almaslmani

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Background: Patients with humeral shaft fractures have two different treatment options. Surgical therapy has lesser risks of non-union, mal-union, and re-intervention than non-surgical therapy. These positive clinical outcomes of the surgical approach make it a preferable treatment option despite the risks of radial nerve palsy and additional surgery-related risk. We aimed to evaluate patients’ outcomes and return to work after surgical vs. non-surgical management of shaft humeral fracture. Methods: We used databases, including PubMed, Medline, and Cochrane Register of Controlled Trials, from 2010 to January 2022 to search for potential randomised controlled trials (RCTs) and cohort studies comparing the patients’ related outcome measures and return to work between surgical and non-surgical management of humerus fracture. Results: After carefully evaluating 1352 articles, we included three RCTs (232 patients) and one cohort study (39 patients). The surgical intervention used plate/nail fixation, while the non-surgical intervention used a splint or brace procedure to manage shaft humeral fracture. The pooled DASH effects of all three RCTs at six (M.D: -7.5 [-13.20, -1.89], P: 0.009) I2:44%) and 12 months (M.D: -1.32 [-3.82, 1.17], p:0.29, I2: 0%) were higher in patients treated surgically than in non-surgical procedures. The pooled constant Murley score at six (M.D: 7.945[2.77,13.10], P: 0.003) I2: 0%) and 12 months (M.D: 1.78 [-1.52, 5.09], P: 0.29, I2: 0%) were higher in patients who received non-surgical than surgical therapy. However, pooled analysis for patients returning to work for both groups remained inconclusive. Conclusion: Altogether, we found no significant evidence supporting the clinical benefits of surgical over non-surgical therapy. Thus, the non-surgical approach remains the preferred therapeutic choice for managing shaft humeral fractures due to its lesser side effects.

Keywords: shaft humeral fracture, surgical treatment, Patient-related outcomes, return to work, DASH

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Authors: Alhaji Musa Abdullahi, Usman Abdullahi, Adamu Lawan, Aminu Maidala

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Abstract 16 healthy lactating cows will be randomly selected for the trial and will be randomly divided in to 4 groups with 4 cows in each. They will be kept under similar management condition (conventional management system). Animals of relatively same weight and age will be used. After 11days for adaptation, feed intake and performance of the experimental animals will be determine. Milk sample will be collected at each milking in the morning and afternoon to determine; Milk yield, Milk fat percentage, Solid not fat percentage, Total solid percentage of milk. Cows dung will be observe to determine; Score 1 very loose watery stool, Score 2 semi solid with undigested raw material, Score 3 semi solid with less undigested raw material, Score 4 solid with very less undigested raw material, Score 5 good dung no undigested raw material. At the end of the experiment, blood samples will be analyzed for full blood counts and differentials {White Blood Cells (WBC), Red Blood Cells (RBC), Hemoglobin (Hb), Packed Cell Volume (PCV), Mean Corpuscular Volume (MCV), Mean Corpuscular Hemoglobin (MCH), Mean Corpuscular Hemoglobin Concentration (MCHC), Platelets (PLT), Lymphocytes (LYM), Basophils, Eosinophils and Monocytes Proportion (MXD) and Neutrophils (NEUT)} using automated hematology analyzer. Serum samples will be analyzed for heat shock transcription factors, heat shock proteins and hormones (Serum glucocorticoid, prolactin and cortisol). Moreover, biochemical analysis will also be conducted to check for Total protein (TP), Albumen (ALB), Globulin (GBL), Total cholesterol (TCH), glucose (G), sodium (Na+), potassium (K+), chloride (Cl-) and pH. Keywords: Lactating cows, milk composition, dung score and blood parameters.

Keywords: Lactating cows , Milk yield , Dung score , Blood parameters

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Authors: Sharmila Dahal Paudel

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Background: There are around twenty-four thousand to twenty-eight thousand Female Sex Workers in Nepal. FSWs are the vulnerable groups for sexually transmitted infections (STIs) and human immunodeficiency virus (HIV) infections which directly and indirectly ease to reduce the quality of life of such groups. Due to their highly marginalized status, FSWs in Nepal have limited access to information about reproductive health and safe sex practices. The objectives of the study are to assess the quality of life of female sex workers and the factors affecting them. Materials and Methods: A descriptive cross-sectional study with methodological triangulation was conducted among 108 FSWs on the basis of service record of selected organization of Pokhara valley. The complete enumerative sampling was used to select FSWs. Structured interview schedule, WHOQOL-BREF and in-depth questionnaire were used to collect the data. The descriptive and inferential statistics were used to interpret the result. Results: The mean age of participants were 23.44 years and the mean quality of life score was 174.06 ranging from 56.54 to 370.78. Among the domain scores, the mean score is highest in social domain (55.89) followed by physical (45.42), psychological (39.27) and the environmental (34.23). Regarding the association of QOL with socio-demographic, occupation and health-related variables, the multi-linear regression suggests that the satisfaction with occupation was highly significant with the total QOL score (B=-50.50, SE=10.46; p= <0.001) and there is negative relation between QOL and feeling of exploitation and facing STI problems. This means those who feels exploited have significantly less QOL comparing with those who did not feel the same. In correlation analysis, all the domains are positively co-related with each domain which is found to be significant at 1% level of significance. Conclusion: The highest mean score was in social domain, and the lowest is in environmental domain which suggests that the items included in environmental domains could not be utilized or hindrance were there.

Keywords: FSWs, HIV, QOL, WHOQOL-BREF

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Authors: Laith K. Abbas, Xiaoting Rui, Pier Marzocca

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Aerospace systems, generally speaking, are inherently nonlinear. These nonlinearities may modify the behavior of the system. However, nonlinearities in an aeroelastic system can be divided into structural and aerodynamic. Structural nonlinearities can be subdivided into distributed and concentrated ones. Distributed nonlinearities are spread over the whole structure representing the characteristic of materials and large motions. Concentrated nonlinearities act locally, representing loose of attachments, worn hinges of control surfaces, and the presence of external stores. The concentrated nonlinearities can be approximated by one of the classical structural nonlinearities, namely, cubic, free-play and hysteresis, or by a combination of these, for example, a free-play and a cubic one. Compressibility, aerodynamic heating, separated flows and turbulence effects are important aspects that result in nonlinear aerodynamic behavior. An issue related to the low-speed flutter and its catastrophic/benign character represented by Limit Cycle Oscillation (LCO) of all-movable fin, as well to their control is addressed in the present work. To the approach of this issue: (1) Quasi-Steady (QS) Theory and Computational Fluid Dynamics (CFD) of subsonic flow are implemented, (2) Flutter motion equations of a two-dimensional typical section with cubic nonlinear stiffness in the pitching direction and free play gap are established, (3) Uncoupled bending/torsion frequencies of the selected fin are computed using recently developed Transfer Matrix Method of Multibody System Dynamics (MSTMM), and (4) Time simulations are carried out to study the bifurcation behavior of the aeroelastic system. The main objective of this study is to investigate how the LCO and chaotic behavior are influenced by the coupled aeroelastic nonlinearities and intend to implement a control capability enabling one to control both the flutter boundary and its character. By this way, it may expand the operational envelop of the aerospace vehicle without failure.

Keywords: aeroelasticity, CFD, MSTMM, flutter, freeplay, fin

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Authors: Varsha Kheradiya, Ganga Prasad Pandey

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The use of wearable antennas is rising because wireless devices become small. The wearable antenna is part of clothes used in communication applications, including energy harvesting, medical application, navigation, and tracking. In current years, Antennas embroidered on clothes, conducting antennas based on fabric, polymer embedded antennas, and inkjet-printed antennas are all attractive ways. Also shows the analysis required for wearable antennas, such as wearable antennae interacting with the human body. The primary requirements for the antenna are small size, low profile minimizing radiation absorption by the human body, high efficiency, structural integrity to survive worst situations, and good gain. Therefore, research in energy harvesting, biomedicine, and military application design is increasingly favoring flexible wearable antennas. Textile materials that are effectively used for designing and developing wearable antennas for body area networks. The wireless body area network is primarily concerned with creating effective antenna systems. The antenna should reduce their size, be lightweight, and be adaptable when integrated into clothes. When antennas integrate into clothes, it provides a convenient alternative to those fabricated using rigid substrates. This paper presents a study of U slot loaded wearable textile antenna. U slot patch antenna design is illustrated for wideband from 1GHz to 6 GHz using textile material jeans as substrate and pure copper polyester taffeta fabric as conducting material. This antenna design exhibits dual band results for WLAN at 2.4 GHz and 3.6 GHz frequencies. Also, study U slot position horizontal and vertical shifting. Shifting the horizontal positive X-axis position of the U slot produces the third band at 5.8 GHz.

Keywords: microstrip patch antenna, textile material, U slot wearable antenna, wireless body area network

Procedia PDF Downloads 90