Search results for: uniform modules

Authors: Arash Rahmani, Ahmad Ghanbari, Abbas Baghernezhad, Babak Safaei

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In the design of parallel manipulators, usually mean value of a dexterity measure over the workspace volume is considered as the objective function to be used in optimization algorithms. The mentioned indexes in a hybrid parallel manipulator (HPM) are quite complicated to solve thanks to infinite solutions for every point within the workspace of the redundant manipulators. In this paper, spatial isotropic design axioms are extended as a well-known method for optimum design of manipulators. An upper limit for the isotropy measure of HPM is calculated and instead of computing and minimizing isotropy measure, minimizing the obtained limit is considered. To this end, two different objective functions are suggested which are obtained from objective functions of comprising modules. Finally, by using genetic algorithm (GA), the best geometric parameters for a specific hybrid parallel robot which is composed of two modified Gough-Stewart platforms (MGSP) are achieved.

Keywords: hybrid manipulator, spatial isotropy, genetic algorithm, optimum design

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Authors: Waheed Zahra, Mohamed El-Beltagy, Ashraf El Mhlawy, Reda Elkhadrawy

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In this paper, we consider singular perturbation reaction-diffusion boundary value problems, which contain a small uncertain perturbation parameter. To solve these problems, we propose a numerical method which is based on an exponential spline and Shishkin mesh discretization. While interval analysis principle is used to deal with the uncertain parameter, sensitivity analysis has been conducted using different methods. Numerical results are provided to show the applicability and efficiency of our method, which is ε-uniform convergence of almost second order.

Keywords: singular perturbation problem, shishkin mesh, two small parameters, exponential spline, interval analysis, sensitivity analysis

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Authors: Souhila Bendenia, Chahrazed Bendenia, Hanaa Merad-Dib, Sarra Merabet, Samia Moulebhar, Sid Ahmed Khantar

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Today, environmental pollution is a major concernworldwide, threateninghumanhealth. Various techniques have been used, includingdegradation, filtration, advancedoxidationprocesses, ion exchange, membrane processes, and adsorption. The latter is one of the mostsuitablemethods, usinghighly efficient materials. In this study, NaX zeolite was modified with Cu or Ni at various rates. Following ion exchange, the samples were characterized by XRD, BET and SEM/EDX. After characterization, the exchanged zeolites were used for adsorption of various pollutants as CO2. Different thermodynamic parameters were studied such as Qst. XRD results show that the most intense peaks characteristic of 13X persist after the exchange reaction for all samples. The SEM images of our samples have uniform and regular crystal shapes. The results show that ion exhange with Cu or Ni affect the textural properties of X zeolites and prove that the exchange zeolites can be used as an adsorbent for depollution.

Keywords: X zeolites (NaX), ion exchange, characterization, adsorption

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Authors: E. C. du Plessis

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Teaching practice is a major component of teacher education and the preparation of teachers for the real-life classroom throughout the world. Learning is seen as a constructive process, whether it is classroom based or takes place by means of distance education. Blending theory and practice with effective education in distance context as part of situated learning is crucial. Therefore, the aim of this research was to determine distance education student teachers' classroom readiness on completion of the teaching practice modules of their Postgraduate Certificate in Education (PGCE) course. A qualitative research approach was used for the collection, analysis, and interpretation of data. A total of 15 student teachers enrolled at the College of Education of an ODL (Open and Distance Learning) institution were selected and volunteered to participate in the research. In the light of the results of the research, it is recommended that more attention is given to the interaction between mentor teachers, academic lecturers, and student teachers, as well as the expectations and responsibilities of these role-players.

Keywords: communities of practice, mentor teachers, open and distance learning, practicum, professional development, student teachers, teaching practice

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Authors: M. E. Marwan, A. R. Madar, N. Fuad

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Mobile learning (m-learning) is a new method in teaching and learning process which combines technology of mobile device with learning materials. It can enhance student's engagement in learning activities and facilitate them to access the learning materials at anytime and anywhere. In Kolej Poly-Tech Mara (KPTM), this method is seen as an important effort in teaching practice and to improve student learning performance. The aim of this paper is to discuss the development of m-learning application called Mobile EEF Learning System (MEEFLS) to be implemented for Electric and Electronic Fundamentals course using Flash, XML (Extensible Markup Language) and J2ME (Java 2 micro edition). System Development Life Cycle (SDLC) was used as an application development approach. It has three modules in this application such as notes or course material, exercises and video. MEELFS development is seen as a tool or a pilot test for m-learning in KPTM.

Keywords: flash, mobile device, mobile learning, teaching and learning, SDLC, XML

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Authors: Mokhtar Bouazza

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In this paper, the simplified theory will be used to predict the thermoelastic buckling behavior of rectangular functionally graded plates. The material properties of the functionally graded plates are assumed to vary continuously through the thickness, according to a simple power law distribution of the volume fraction of the constituents. The simplified theory is used to obtain the buckling of the plate under different types of thermal loads. The thermal loads are assumed to be uniform, linear, and non-linear distribution through the thickness. Additional numerical results are presented for FGM plates that show the effects of various parameters on thermal buckling response.

Keywords: buckling, functionally graded, plate, simplified higher-order deformation theory, thermal loading

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Authors: Lawrence Meda, Christopher Dumas, Moses Moyo, Zayd Waghid

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As a result of some schools embracing technology to enhance students’ learning experiences in the digital era, the Faculty of Education at a University of Technology in South Africa has mandated lecturers to scale up their utilisation of technology in their teaching. Lecturers have been challenged to utilise the institution’s Learning Management System - Blackboard among other technologies - to adequately prepare trainee teachers to be able to teach competently in schools. The purpose of this study is to investigate the extent to which lecturers are utilising Blackboard to enhance their teaching. The study will be conducted using a quantitative approach, and its paradigmatic position will be positivist. The study will be done as a case study of the university’s Faculty of Education. Data will be extracted from all 100 lecturers’ Blackboard sites according to their respective modules, and it will be analysed using the four pillars of Blackboard as a conceptual framework. It is presumed that there is an imbalance on the lecturers’ utilisation of the four pillars of Blackboard as the majority use it as a content dumping site.

Keywords: blackboard, digital, education, technology

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Authors: Sopida Vacharasukpo, Sudarat Khwan-On

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This paper proposes a high step-up DC-DC converter topology for renewable energy system applications. The proposed converter employs only a single power switch instead of using several switches. Compared to the conventional DC-DC step-up converters the higher voltage gain with small output ripples can be achieved by using the proposed high step-up DC-DC converter topology. It can step up the low input voltage (20-50Vdc) generated from the photovoltaic modules to the high output voltage level approximately 600Vdc in order to supply the three-phase inverter fed the three-phase motor drive. In this paper, the operating principle of the proposed converter topology and its control strategy under the continuous conduction mode (CCM) are described. Finally, simulation results are shown to demonstrate the effectiveness of the proposed high step-up DC-DC converter with its control strategy to increase the voltage step-up conversion ratio.

Keywords: DC-DC converter, high step-up ratio, renewable energy, single switch

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Authors: Ashley Hobson, Ashley Efaw

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Professionalism is an essential skill for clinicians, particularly for Occupational Therapy Providers (OTPs). The World Federation of Occupational Therapy (WFOT) Guiding Principles for Ethical Occupational Therapy and American Occupational Therapy Association (AOTA) Code of Ethics establishes expectations for professionalism among OTPs, emphasizing its importance in the field. However, the teaching and assessment of professionalism vary across OTP programs. The flexibility provided by the country standards allows programs to determine their own approaches to meeting these standards, resulting in inconsistency. Educators in both academic and fieldwork settings face challenges in objectively assessing and providing feedback on student professionalism. Although they observe instances of unprofessional behavior, there is no standardized assessment measure to evaluate professionalism in OTP students. While most students are committed to learning and applying professionalism skills, they enter OTP programs with varying levels of proficiency in this area. Consequently, they lack a uniform understanding of professionalism and lack an objective means to self-assess their current skills and identify areas for growth. It is crucial to explicitly teach professionalism, have students to self-assess their professionalism skills, and have OTP educators assess student professionalism. This approach is necessary for fostering students' professionalism journeys. Traditionally, there has been no objective way for students to self-assess their professionalism or for educators to provide objective assessments and feedback. To establish a uniform approach to professionalism, the authors incorporated professionalism content into our curriculum. Utilizing an operational definition of professionalism, the authors integrated professionalism into didactic, fieldwork, and capstone courses. The complexity of the content and the professionalism skills expected of students increase each year to ensure students graduate with the skills to practice in accordance with the WFOT Guiding Principles for Ethical Occupational Therapy Practice and AOTA Code of Ethics. Two professionalism assessments were developed based on the expectations outlined in the both documents. The Professionalism Self-Assessment allows students to evaluate their professionalism, reflect on their performance, and set goals. The Professionalism Assessment for Educators is a modified version of the same tool designed for educators. The purpose of this workshop is to provide educators with a framework and tools for assessing student professionalism. The authors discuss how to integrate professionalism content into OTP curriculum and utilize professionalism assessments to provide constructive feedback and equitable learning opportunities for OTP students in academic, fieldwork, and capstone settings. By adopting these strategies, educators can enhance the development of professionalism among OTP students, ensuring they are well-prepared to meet the demands of the profession.

Keywords: professionalism, assessments, student learning, student preparedness, ethical practice

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Authors: David Tena-Gago, Jose M. Alcaraz Calero, Qi Wang

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The evolution and integration of automated vehicles have become more and more tangible in recent years. State-of-the-art technological advances in the field of camera-based Artificial Intelligence (AI) and computer vision greatly favor the performance and reliability of the Advanced Driver Assistance System (ADAS), leading to a greater knowledge of vehicular operation and resembling human behavior. However, the exclusive use of this technology still seems insufficient to control vehicular operation at 100%. To reveal the degree of accuracy of the current camera-based automated driving AI modules, this paper studies the structure and behavior of one of the main solutions in a controlled testing environment. The results obtained clearly outline the lack of reliability when using exclusively the AI model in the perception stage, thereby entailing using additional complementary sensors to improve its safety and performance.

Keywords: accuracy assessment, AI-driven mobility, artificial intelligence, automated vehicles

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Authors: Omar Masaud Almrhag, Frage Lhadi Abookleesh

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Different types of food like banana, potato and chicken affect the quality of oil during deep fat frying. The changes in the quality of oil were evaluated and compared. Four different types of edible oils, namely, corn oil, soybean, canola, and palm oil were used for deep fat frying at 180°C ± 5°C for 5 h/d for six consecutive days. A potato was sliced into 7-8 cm length wedges and chicken was cut into uniform pieces of 100 g each. The parameters used to assess the quality of oil were total polar compound (TPC), iodine value (IV), specific extinction E1% at 233 nm and 269 nm, fatty acid composition (FAC), free fatty acids (FFA), viscosity (cp) and changes in the thermal properties. Results showed that, TPC, IV, FAC, Viscosity (cp) and FFA composition changed significantly with time (P< 0.05) and type of food. Significant differences (P< 0.05) were noted for the used parameters during frying of the above mentioned three products.

Keywords: frying potato, chicken, frying deterioration, quality of oil

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Authors: M. El Hajji, A. Hallaoui, L. Bazzi, A. Benlhachemi, Lh. Bazzi, M. Hilali, O. Jbara, A. Tara, B. Bakiz

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The cathodic electro deposition of the cuprite Cu2O by chrono potentiometry is performed on two types of electrodes "titanium and stainless steel", in a basic medium containing the precursor of copper. The plot produced vs SCE, shows the formation of a brown layer on the electrode surface. The chrono potentiometric recording made between - 0.2 and - 1 mA/cm2, has allowed us to have a deposit having different morphologies and structural orientation obtained as a function of the variation of many parameters. The morphology, the size of crystals, and the phase of the deposits produced were studied by conventional techniques of analysis of the solid, particularly the X-ray diffraction (XRD), scanning electron microscopy analysis (SEM) and quantitative chemical analysis (EDS). The results will be presented and discussed, they show that the majority of deposits are pure and uniform.

Keywords: cathodic electrodeposition, cuprite Cu2O, XRD, SEM, EDS analysis

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Authors: T. S. Yang, J. H. Liang

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This study applies the finite element method (FEM) to predict maximum forging load, effective stress distribution, effective strain distribution, workpiece temperature temperature in spiral bevel gear forging of AISI 1015. Maximum forging load, effective stress, effective strain, workpiece temperature are determined for different process parameters, such as modules, number of teeth, helical angle and workpiece temperature of the spiral bevel gear hot forging, using the FEM. Finally, the prediction of the power requirement for the spiral bevel gear hot forging of AISI 1015 is determined.

Keywords: spiral bevel gear, hot forging, finite element method

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Authors: Niina Jallinoja, Anu Moisio

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Focus on adult learning is vital to overcome economic challenges as well as to respond to the demand for new competencies and sustained productivity in the digitalized world economy. Employees of all ages must be able to carry on continuous professional development to remain competitive in the labor market. According to EU policies, countries should offer more flexible opportunities for adult learners who study online and in so-called ‘second chance’ qualification programmes. Traditionally, adult education in Finland has comprised of not only liberal adult education but also the government funding to study for Bachelor, Master's, and Ph.D. degrees in Finnish Universities and Universities of Applied Sciences (UAS). From the beginning of 2021, public funding is allocated not only to degrees but also to courses to achieve new competencies for adult learners in Finland. Consequently, there will be degree students (often younger of age) and adult learners studying in the same evening, online and blended courses. The question is thus: How are combined studies meeting the different needs of degree students and adult learners? Haaga-Helia University of Applied Sciences (UAS), located in the metropolitan area of Finland, is taking up the challenge of continuous learning for adult learners. Haaga-Helia has been reforming the bachelor level education and respective shorter courses from 2019 in the biggest project in its history. By the end of 2023, Haaga-Helia will have a flexible, modular curriculum for the bachelor's degrees of hospitality management, business administration, business information technology, journalism and sports management. Building on the shared key competencies, degree students will have the possibility to build individual study paths more flexibly, thanks to the new modular structure of the curriculum. They will be able to choose courses across all degrees, and thus, build their own unique competence combinations. All modules can also be offered as separate courses or learning paths to non-degree students, both publicly funded and as commercial services for employers. Consequently, there will be shared course implementations for degree studies and adult learners with various competence requirements. The newly designed courses are piloted in parallel of the designing of the curriculum in Haaga-Helia during 2020 and 2021. Semi-structured online surveys are composed among the participants for the key competence courses. The focus of the research is to understand how students in the bachelor programme and adult learners from Open UAE perceive the learning experience in such a diverse learning group. A comparison is also executed between learning methods of in-site teaching, online implementation, blended learning and virtual self-learning courses to understand how the pedagogy is meeting the learning objectives of these two different groups. The new flexible curricula and the study modules are to be designed to fill the most important competence gaps that exist in the Finnish labor markets. The new curriculum will be dynamic and constantly evolving over time according to the future competence needs in the labor market. This type of approach requires constant dialogue between Haaga-Helia and workplaces during and after designing of the shared curriculum.

Keywords: ccompetence development, continuous learning, curriculum, higher education

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Authors: Azzedine Abdedou, Khedidja Bouhadef

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The present study is an analysis of the forced convection heat transfer in porous channel with an oriented jet at the inlet with uniform velocity and temperature distributions. The upper wall is insulated when the bottom one is kept at constant temperature higher than that of the fluid at the entrance. The dynamic field is analysed by the Brinkman-Forchheimer extended Darcy model and the thermal field is traduced by the energy one equation model. The numerical solution of the governing equations is obtained by using the finite volume method. The results mainly concern the effect of Reynolds number, jet angle and thermal conductivity ratio on the flow structure and local and average Nusselt numbers evolutions.

Keywords: forced convection, porous media, oriented confined jet, fluid mechanics

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Authors: Ishak Hashim, Ammar Alsabery

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The problem of conjugate free convection in a square cavity filled with nanofluid and heated from below by spatial wall temperature is studied numerically using the finite difference method. Water-based nanofluid with copper nanoparticles are chosen for the investigation. Governing equations are solved over a wide range of nanoparticle volume fraction (0 ≤ φ ≤ 0.2), wave number ((0 ≤ λ ≤ 4) and thermal conductivity ratio (0.44 ≤ Kr ≤ 6). The results presented for values of the governing parameters in terms of streamlines, isotherms and average Nusselt number. It is found that the flow behavior and the heat distribution are clearly enhanced with the increment of the non-uniform heating.

Keywords: conjugate free convection, square cavity, nanofluid, spatial temperature

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Authors: Ashkan Javadzadegan, Aitak Javadzadegan, Babak Fakhim

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One of possible ways to retard movement of fluid is through applying an external magnetic field. In this regard, this study is focused on the effect of a uniform transverse magnetic field on fluid flow behavior inside a channel with a local symmetric constriction. Also, Ellis Non-Newtonian model is implemented to address the effects of shear-dependent viscosity. According to the results, the flow separation downstream of the constriction can be controlled by applying an external magnetic field and/or manipulating the shear-thinning degree of fluid. It is also demonstrated that pressure drop increases by an increase in the strength of the magnetic field.

Keywords: magnetic field, non-Newtonian, separation, shear thinning

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Authors: Sanjeev Das

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In the present investigation, magnesium strips were produced by twin roll casting (TRC) and melt conditioned twin roll casting (MC-TRC) processes. The microstructures showed uniform fine equiaxed grain morphology in the case of MC-TRC cast samples. In the case of TRC samples elongated grains with centerline segregation was observed. Further investigation showed both the process has different solidification mechanism. Tensile tests were performed at 250–400ºC for both TRC and MCTRC samples. At 250ºC, MC-TRC sample showed significant improvement in strength and ductility. However, at higher temperatures the tensile properties were almost comparable, despite of TRC samples having larger grains compared to MC-TRC samples. It was observed that homogenized MC-TRC samples were easily hot stamped compared to TRC samples.

Keywords: MC-TRC, magnesium alloy, solidification, nucleation

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Authors: Amin Asgarian, Ghyslaine McClure

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Proper seismic evaluation of Non-Structural Components (NSCs) mandates an accurate estimation of floor seismic demands (i.e. acceleration and displacement demands). Most of the current international codes incorporate empirical equations to calculate equivalent static seismic force for which NSCs and their anchorage system must be designed. These equations, in general, are functions of component mass and peak seismic acceleration to which NSCs are subjected to during the earthquake. However, recent studies have shown that these recommendations are suffered from several shortcomings such as neglecting the higher mode effect, tuning effect, NSCs damping effect, etc. which cause underestimation of the component seismic acceleration demand. This work is aimed to circumvent the aforementioned shortcomings of code provisions as well as improving them by proposing a simplified, practical, and yet accurate approach to generate acceleration Floor Design Spectra (FDS) directly from corresponding Uniform Hazard Spectra (UHS) (i.e. design spectra for structural components). A database of 27 Reinforced Concrete (RC) buildings in which Ambient Vibration Measurements (AVM) have been conducted. The database comprises 12 low-rise, 10 medium-rise, and 5 high-rise buildings all located in Montréal, Canada and designated as post-disaster buildings or emergency shelters. The buildings are subjected to a set of 20 compatible seismic records and Floor Response Spectra (FRS) in terms of pseudo acceleration are derived using the proposed approach for every floor of the building in both horizontal directions considering 4 different damping ratios of NSCs (i.e. 2, 5, 10, and 20% viscous damping). Several effective parameters on NSCs response are evaluated statistically. These parameters comprise NSCs damping ratios, tuning of NSCs natural period with one of the natural periods of supporting structure, higher modes of supporting structures, and location of NSCs. The entire spectral region is divided into three distinct segments namely short-period, fundamental period, and long period region. The derived roof floor response spectra for NSCs with 5% damping are compared with the 5% damping UHS and procedure are proposed to generate roof FDS for NSCs with 5% damping directly from 5% damped UHS in each spectral region. The generated FDS is a powerful, practical, and accurate tool for seismic design and assessment of acceleration-sensitive NSCs particularly in existing post-critical buildings which have to remain functional even after the earthquake and cannot tolerate any damage to NSCs.

Keywords: earthquake engineering, operational and functional components (OFCs), operational modal analysis (OMA), seismic assessment and design

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Authors: Priyanka Gupta, Nilanjana Bairagi, Deepti Gupta

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New pathogenic strains of microbes are continually emerging and resistance of bacteria to antibiotics is growing. Hospitals in India have a high burden of infections in their intensive care units and general wards. Rising incidence of hospital infections is a matter of great concern in India. This growth is often attributed to the absence of effective infection control strategies in healthcare facilities. Government, therefore, is looking for cost effective strategies that are effective against HAIs. One possible method is by application of an antimicrobial finish on the uniform. But there are limited studies to show the effect of antimicrobial activity of antimicrobial finish treated nurses’ uniforms in a real hospital set up. This paper proposes a prospective non-destructive sampling technique, based on the use of a detachable fabric patch, to assess the effectiveness of silver based antimicrobial agent across five wards in a tertiary care government hospital in Delhi, India. Fabrics like polyester and polyester cotton blend fabric which are more prevalent for making coats were selected for the study. Polyester and polyester cotton blend fabric was treated with silver based antimicrobial (AM) finish. At the beginning of shift, a composite patch of untreated and treated fabric respectively was stitched on the abdominal region on the left and right side of the washed white coat of participating nurse. At the end of the shift, the patch was removed and taken for bacterial sampling on Brain Heart Infusion (BHI) plates. Microbial contamination on polyester and blend fabrics after 6 hours shift was compared in Brain Heart Infusion broth (BHI). All patches treated with silver based antimicrobial agent showed decreased bacterial counts. Percent reduction in the bacterial colonies after the antimicrobial treatment in both fabrics was 81.0 %. Antimicrobial finish was equally effective in reducing microbial adhesion on both fabric types. White coats of nurses become progressively contaminated during clinical care. Type of fabric used to make the coat can affect the extent of contamination which is higher on polyester cotton blend as compared to 100% polyester. The study highlights the importance of silver based antimicrobial finish in the area of uniform hygiene. Bacterial load can be reduced by using antimicrobial finish on hospital uniforms. Hospital staff uniforms endowed with antimicrobial properties may be of great help in reducing the occurrence and spread of infections.

Keywords: antimicrobial finish, bacteria, infection control, silver, white coat

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Authors: Stanley Fore, Gaetan Ngabonziza

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In spite of the need for skilled labour in South Africa, tertiary education graduates are increasingly faced with unemployment, which poses a serious obstacle to the economic growth of the country. This paper is an outcome of the study that investigated students’ perceptions on the role of entrepreneurship education in enhancing graduates’ self-employment. The study was descriptive in nature and used a survey questionnaire to answer questions pertaining to the extent to which entrepreneurship education is important in enhancing self-employment endeavours. Collected data were analysed using of the statistical software for social science (SPSS) for descriptive statistics in the form of tables and charts. The study found that entrepreneurship education is critical in providing knowledge and skills that are required to succeed in self-employment. As one module of entrepreneurship does not ensure self-employment orientation or more positive expectations about entrepreneurial abilities and careers, this study suggests that students, irrespective of their field of study, should be given entrepreneurship modules in every academic year. This will help in reminding them that their success does not solely rely on their ability to find a better-paying employment but also on their ability to employ themselves.

Keywords: entrepreneurship, education, self-employment, students

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Authors: Sehrish Khan

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The present study investigated the attitude of university students towards semester system and teachers with a specific objective of finding problems faced by students in semester system. 10 focus group discussions were conducted among students in five Universities of Hazara Division of KPK regarding their knowledge and attitudes about semester system and problems they faced due to this system and teacher’s attitude. The key findings were the problems like favoritism, gender biased ness, racial biased ness, biased ness in marking, relative marking, harassment, using students for personal tasks and authoritarian attitude from teachers’ side and the heavy tasks in less time which are causing stress among students. It was recommended that proper training and monitoring system should be maintained for evaluation of teachers to minimize the corruption in this sacred profession and maximize the optimal functioning. The information gathered in this research can be used to develop training modules for University teachers.

Keywords: university teachers, favoritism, biasedness, harassment

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Authors: B. Bouktif, M. Gaidi, M. Benrabha

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Metal-nano particle-assisted chemical etching is an extraordinary developed wet etching method of producing uniform semiconductor nanostructure (nanowires) from the patterned metallic film on the crystalline silicon surface. The metal films facilitate the etching in HF and H2O2 solution and produce silicon nanowires (SiNWs). Creation of different SiNWs morphologies by changing the etching time and its effects on optical and optoelectronic properties was investigated. Combination effect of formed SiNWs and stain etching treatment in acid (HF/HNO3/H2O) solution on the surface morphology of Si wafers as well as on the optical and optoelectronic properties are presented in this paper.

Keywords: semiconductor nanostructure, chemical etching, optoelectronic property, silicon surface

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Authors: Tokuei Sako

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Laser-induced current in a quasi-one-dimensional nanostructure has been studied by a model of a few electrons confined in a 1D electrostatic potential coupled to electrodes at both ends and subjected to a pulsed laser field. The time-propagation of the one- and two-electron wave packets has been calculated by integrating the time-dependent Schrödinger equation directly by the symplectic integrator method with uniform Fourier grid. The temporal behavior of the resultant light-induced current in the studied systems has been discussed with respect to the lifetime of the quasi-bound states formed when the static bias voltage is applied.

Keywords: pulsed laser field, nanowire, electron wave packet, quantum dots, time-dependent Schrödinger equation

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Authors: Hamed Sarbazy, Zohre Gholipour Haftkhani, Ali Safari, Pejman Hosseiniun

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Scientific and industrial progress in the past two decades has resulted in energy distribution systems based on power electronics, as an enabling technology in various industries and building management systems can be considered. Grading and standardization module power electronics systems and its use in a distributed control system, a strategy for overcoming the limitations of using this system. The purpose of this paper is to investigate strategies for scheduling and control structure of standard modules is a power electronic systems. This paper introduces the classical control methods and disadvantages of these methods will be discussed, The hierarchical control as a mechanism for distributed control structure of the classification module explains. The different levels of control and communication between these levels are fully introduced. Also continue to standardize software distribution system control structure is discussed. Finally, as an example, the control structure will be presented in a DC distribution system.

Keywords: application management, hardware management, power electronics, building blocks

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Authors: Raksit Nanthatanti, Jarruwat Charoensuk, S. Hirai, Manop Masomtop

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In this study, the effect of channel geometry and operating circumstances on a liquid cooling plate for Lithium-ion Battery modules has been investigated Inlet temperature, water velocity, and channel count were the main factors. According to the passage, enhancing the number of cooling channels[2,3,4,6channelperbases] will affect water flow distribution caused by varying the velocity inlet inside the cooling block[0.5,1.0,1.5,2.0 m/sec] and intake temperatures[25,30,35,40oC], The findings indicate that the battery’s temperature drops as the number of channels increases. The maximum battery's operating temperature [45 oC] rises, but ∆t is needed to be less than 5 oC [v≤1m/sec]. Maximum temperature and local temperature difference of the battery change significantly with the change of the velocity inlet in the cooling channel and its thermal conductivity. The results of the simulation will help to increase cooling efficiency on the cooling system for Li-ion Battery based on a Mini channel in a liquid-cooling configuration

Keywords: cooling efficiency, channel count, lithium-ion battery, operating

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Authors: Z. Aziz, S. Terkhi, Y. Sefir, R. Djelti, S. Bentata

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The effect of a uniform electric field across multi-barrier systems (InAs/InxGa1-xAs) is exhaustively explored by a computational model using exact Airy function formalism and the transfer-matrix technique. In the case of biased DFHBSL structure a strong reduction in transmission properties was observed and the width of the mini-band structure linearly decreases with the increase of the applied bias. This is due to the confinement of the states in the mini-band structure, which becomes increasingly important (Wannier-Stark Effect).

Keywords: dimer fibonacci height barrier superlattices, singular extended state, exact Airy function and transfer matrix formalism, bioinformatics

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Authors: Aziz Zoubir, Sefir Yamina, Djelti Redouan, Bentata Samir

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The effect of a uniform electric field across multibarrier systems (GaAs/AlxGa1-xAs) is exhaustively explored by a computational model using exact Airy function formalism and the transfer-matrix technique. In the case of biased Dimer Fibonacci Height Barrier superlattices (DFHBSL) structure a strong reduction in transmission properties was observed and the width of the miniband structure linearly decreases with the increase of the applied bias. This is due to the confinement of the states in the miniband structure, which becomes increasingly important (Wannier-Stark effect).

Keywords: Dimer Fibonacci Height Barrier superlattices, singular extended states, exact Airy function, transfer matrix formalism

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Authors: A. Lovascio, A. D’Orazio, V. Centonze

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From several years till now the aerospace industry is developing more and more small satellites for Low-Earth Orbit (LEO) missions. Such satellites have a low cost of making and launching since they have a size and weight smaller than other types of satellites. However, because of size limitations, small satellites need integrated electronic equipment based on digital logic. Moreover, the LEOs require telecommunication modules with high throughput to transmit to earth a big amount of data in a short time. In order to meet such requirements, in this paper we propose a Telemetry, Tracking & Command module optimized through the use of the Commercial Off-The-Shelf components. The proposed approach exploits the major flexibility offered by these components in reducing costs and optimizing the performance. The method has been applied in detail for the design of the front-end receiver, which has a low noise figure (1.5 dB) and DC power consumption (smaller than 2 W). Such a performance is particularly attractive since it allows fulfilling the energy budget stringent constraints that are typical for LEO small platforms.

Keywords: COTS, LEO, small-satellite, TT&C

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Authors: Hamed Bagheri, Seyd Javid Shariati

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The effects of type and amount of solvent on lubricant which is used in disposable medical devices are investigated in this article. Two kinds of common solvent, n-Hexane and n-Heptane, are used. The mechanical behavior of syringe has shown that n-Heptane has better mixing ratio and also more effective spray process in the barrel of syringe than n-Hexane because of similar solubility parameter to silicon oil. The results revealed that movement of plunger in the barrel increases when pure silicone is used because non-uniform film is created on the surface of barrel, and also, it seems that the form of silicon is converted from oil to gel due to sterilization process. The results showed that the convenient mixing ratio of solvent/lubricant oil is 80/20.

Keywords: disposal medical devices, lubricant oil, solvent effect, solubility parameter

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