Search results for: higher order inertia
21475 The Asia-European Union (EU) Traffic Safety Benchmarking
Authors: Ghazwan Al-Haji
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Traffic safety has become a major concern in Southeast Asia due to the increasing number of road accidents resulting in fatalities and injuries. Southeast Asia has one of the highest road traffic fatality rates in the world, in terms of both population and number of cars, nearly six times higher than the EU region. One of the reasons for this concerning trend is the increasing share of motorcycles as a form of transportation throughout Southeast Asia. The purpose of this study is to benchmark traffic safety situations and statistics in six countries in Asia and the EU, which Indonesia, Malaysia, Vietnam, Italy, Portugal and Sweden. The research will assess the priorities and causes of road accidents in the target nations. Further, the study will analyze the existing practices and promote best practices that can be implemented toward safer roads in Asian target countries. In order to achieve this goal, the study categorizes various factors contributing to traffic accidents and best practices into 4 pillars (Safer Behavior, Safer Roads, Safer Vehicles and Road Safety Management). The result of the study consists of a list of recommendations that can be applied by policymakers to promote safer roads in Asia towards 2030. The study is co-financed by the EU project ASIASAFE.Keywords: traffic safety, ASIASAFE, Southeast Asia, EU project
Procedia PDF Downloads 7221474 Antioxidant Activity of Some Important Indigenous Plant Foods of the North Eastern Region of India
Authors: L. Bidyalakshmi, R. Ananthan, T. Longvah
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Antioxidants are substances that can prevent or delay oxidative damage of lipids, proteins and nucleic acids by reactive oxygen species. These help in lowering incidence of degenerative diseases such as cancer, arthritis, atherosclerosis, heart disease, inflammation, brain dysfunction and acceleration of the ageing process. The north eastern part of India falls among the global hotspots of biodiversity. Over the years, the local communities in the region have developed ingenious uses of many wild plants within their environment as food sources. Many of these less familiar foods form an integral part of the diet of these communities, and some are traditionally valued for its therapeutic effects. So the study was carried to estimate the antioxidant activity of some of these indigenous foods. Twenty-eight indigenous plant foods were studied for their antioxidant activity. Antioxidant activities were determined by using DPPH (2, 2-diphenyl-1-picrylhydrazyl) assay, FRAP (Ferric Reducing Antioxidant Power) assay and SOSA (Super Oxide Scavenging Assay). Out of the twenty-eight plant foods, there were thirteen leafy vegetables, four fruits, five roots and tubers, four spices and two mushrooms. Water extract and methanol extract of the samples were used for the analysis. The leafy vegetable samples exhibited antioxidant capacity with IC50 ranging from 8-1414 mg/ml for lipid extract and 34-37878 mg/ml for aqueous extract in DPPH assay. Total FRAP value ranging from 58-1005 mmol FeSO4 Eq/100g of the sample, which is comparatively higher than the antioxidant capacity of some commonly consumed leafy vegetables. In SOSA, water extract of leafy vegetables show a range of 0.05-193.68 µmol ascorbic acid equivalent/g of the samples. While the methanol extract of the samples show 0.20-21.94 µmol Trolox equivalent/g of the samples. Polygonum barbatum, Wendlandia glabrata and Polygonum posumbu have higher antioxidant activity among the leafy vegetables analysed. Among the fruits, Rhus hookerii showed the highest antioxidant activities in both FRAP and SOSA methods while Spondias magnifera exhibited higher antioxidant activity in DPPH method. Alocasia cucullata exhibited higher antioxidant activity in DPPH and FRAP assays while Alpinia galanga showed higher antioxidant activity in SOSA assay when compared to the other samples of roots and tubers. Elsholtzia communis showed high antioxidant activity in all the three parameters among the spices. For the mushrooms, Pleurotus ostreatus exhibited higher antioxidant activity than Auricularia delicate in DPPH and SOSA. The samples analysed exhibited antioxidant activity at varying levels and some exhibited higher antioxidant activity than the commonly consumed foods. So consumption of these less familiar foods may play a role in preventing human disease in which free radicals are involved. Further studies on these food samples on phytonutrients and its contribution to the antioxidant activities are required.Keywords: antioxidant activity, DPPH, FRAP, SOSA
Procedia PDF Downloads 28021473 Developing a Decision-Making Tool for Prioritizing Green Building Initiatives
Authors: Tayyab Ahmad, Gerard Healey
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Sustainability in built environment sector is subject to many development constraints. Building projects are developed under different requirements of deliverables which makes each project unique. For an owner organization, i.e., a higher-education institution, involved in a significant building stock, it is important to prioritize some of the sustainability initiatives over the others in order to align the sustainable building development with organizational goals. The point-based green building rating tools i.e. Green Star, LEED, BREEAM are becoming increasingly popular and are well-acknowledged worldwide for verifying a sustainable development. It is imperative to synthesize a multi-criteria decision-making tool that can capitalize on the point-based methodology of rating systems while customizing the sustainable development of building projects according to the individual requirements and constraints of the client organization. A multi-criteria decision-making tool for the University of Melbourne is developed that builds on the action-learning and experience of implementing Green Buildings at the University of Melbourne. The tool evaluates the different sustainable building initiatives based on the framework of Green Star rating tool of Green Building Council of Australia. For each different sustainability initiative the decision-making tool makes an assessment based on at least five performance criteria including the ease with which a sustainability initiative can be achieved and the potential of a sustainability initiative to enhance project objectives, reduce life-cycle costs, enhance University’s reputation, and increase the confidence in quality construction. The use of a weighted aggregation mathematical model in the proposed tool can have a considerable role in the decision-making process of a Green Building project by indexing the Green Building initiatives in terms of organizational priorities. The index value of each initiative will be based on its alignment with some of the key performance criteria. The usefulness of the decision-making tool is validated by conducting structured interviews with some of the key stakeholders involved in the development of sustainable building projects at the University of Melbourne. The proposed tool is realized to help a client organization in deciding that within limited resources which sustainability initiatives and practices are more important to be pursued than others.Keywords: higher education institution, multi-criteria decision-making tool, organizational values, prioritizing sustainability initiatives, weighted aggregation model
Procedia PDF Downloads 23421472 The Design of Intelligent Classroom Management System with Raspberry PI
Authors: Sathapath Kilaso
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Attendance checking in the classroom for student is object to record the student’s attendance in order to support the learning activities in the classroom. Despite the teaching trend in the 21st century is the student-center learning and the lecturer duty is to mentor and give an advice, the classroom learning is still important in order to let the student interact with the classmate and the lecturer or for a specific subject which the in-class learning is needed. The development of the system prototype by applied the microcontroller technology and embedded system with the “internet of thing” trend and the web socket technique will allow the lecturer to be alerted immediately whenever the data is updated.Keywords: arduino, embedded system, classroom, raspberry PI
Procedia PDF Downloads 37621471 Improvement of Central Composite Design in Modeling and Optimization of Simulation Experiments
Authors: A. Nuchitprasittichai, N. Lerdritsirikoon, T. Khamsing
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Simulation modeling can be used to solve real world problems. It provides an understanding of a complex system. To develop a simplified model of process simulation, a suitable experimental design is required to be able to capture surface characteristics. This paper presents the experimental design and algorithm used to model the process simulation for optimization problem. The CO2 liquefaction based on external refrigeration with two refrigeration circuits was used as a simulation case study. Latin Hypercube Sampling (LHS) was purposed to combine with existing Central Composite Design (CCD) samples to improve the performance of CCD in generating the second order model of the system. The second order model was then used as the objective function of the optimization problem. The results showed that adding LHS samples to CCD samples can help capture surface curvature characteristics. Suitable number of LHS sample points should be considered in order to get an accurate nonlinear model with minimum number of simulation experiments.Keywords: central composite design, CO2 liquefaction, latin hypercube sampling, simulation-based optimization
Procedia PDF Downloads 16921470 Student Participation in Higher Education Quality Assurance Processes
Authors: Tomasz Zarebski
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A very important element of the education system is its evaluation procedure. Each education system should be systematically evaluated and improved. Among the criteria subject to evaluation, attention should be paid to the following: structure of the study programme, implementation of the study programme, admission to studies, verification of learning outcomes achievement by students, giving credit for individual semesters and years, and awarding diplomas, competence, experience, qualifications and the number of staff providing education, staff development, and in-service training, education infrastructure, cooperation with social and economic stakeholders on the development, conditions for and methods of improving the internationalisation of education provided as part of the degree programme, supporting learning, social, academic or professional development of students and their entry on the labour market, public access to information about the study programme and quality assurance policy. Concerning the assessment process and the individual assessment indicators, the participation of students in these processes is essential. The purpose of this paper is to analyse the rules of student participation in accreditation processes on the example of individual countries in Europe. The rules of students' participation in the work of accreditation committees and their influence on the final grade of the committee were analysed. Most of the higher education institutions follow similar rules for accreditation. The general model gives the individual institution freedom to organize its own quality assurance, as long as the system lives up to the criteria for quality and relevance laid down in the particular provisions. This point also applies to students. The regulations of the following countries were examined in the legal-comparative aspect: Poland (Polish Accreditation Committee), Denmark (The Danish Accreditation Institution), France (High Council for the Evaluation of Research and Higher Education), Germany (Agency for Quality Assurance through Accreditation of Study Programmes) and Italy (National Agency for the Evaluation of Universities and Research Institutes).Keywords: accreditation, student, study programme, quality assurance in higher education
Procedia PDF Downloads 17321469 A Research on Glass Ceiling Syndrome: Career Barriers of Women Academics
Authors: Serdar Öge, Alpay Karasoy, Özlem Kara
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Although women have merit in their jobs, they still are located very few in the top management in many sectors. There are many causes of such situation. Such a situation creates obstacles; especially invisible ones are called “glass ceiling syndrome”. Also, studies which handle this subject in academic community are very few. The aim of this research is to reach the results about glass ceiling obstacles in terms of female teaching staff (academics) working in higher education institutions. To this end, our study was performed on female academics working at Selcuk University, Konya / Turkey. Our study's main aim can be expressed as to determine whether there are glass ceiling obstacles for female academics working at the higher education institution in question, to measure their glass ceiling perceptions and, thus, to identify what the glass ceiling barrier components for them to promotion to senior management positions are.Keywords: career, career barriers, glass ceiling syndrome, academics
Procedia PDF Downloads 33721468 Meta-Magnetic Properties of LaFe₁₂B₆ Type Compounds
Authors: Baptiste Vallet-Simond, Léopold V. B. Diop, Olivier Isnard
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The antiferromagnetic itinerant-electron compound LaFe₁₂B₆ occupies a special place among rare-earth iron-rich intermetallic; it presents exotic magnetic and physical properties. The unusual amplitude-modulated spin configuration defined by a propagation vector k = (¼, ¼, ¼), remarkably weak Fe magnetic moment (0.43 μB) in the antiferromagnetic ground state, especially low magnetic ordering temperature TN = 36 K for an Fe-rich phase, a multicritical point in the complex magnetic phase diagram, both normal and inverse magnetocaloric effects, and huge hydrostatic pressure effects can be highlighted as the most relevant. Both antiferromagnetic (AFM) and paramagnetic (PM) states can be transformed into the ferromagnetic (FM) state via a field-induced first-order metamagnetic transition. Of particular interest is the low-temperature magnetization process. This process is discontinuous and evolves unexpected huge metamagnetic transitions consisting of a succession of steep magnetization jumps separated by plateaus, giving rise to an unusual avalanche-like behavior. The metamagnetic transition is accompanied by giant magnetoresistance and large magnetostriction. In the present work, we report on the intrinsic magnetic properties of the La₁₋ₓPrₓFe₁₂B₆ series of compounds exhibiting sharp metamagnetic transitions. The study of the structural, magnetic, magneto-transport, and magnetostrictive properties of the La₁₋ₓPrₓFe₁₂B₆ system was performed by combining a wide variety of measurement techniques. Magnetic measurements were performed up to µ0H = 10 T. It was found that the proportion of Pr had a strong influence on the magnetic properties of this series of compounds. At x=0.05, the ground state at 2K is that of an antiferromagnet, but the critical transition field Hc has been lowered from Hc = 6T at x = 0 to Hc = 2.5 Tat x=0.05. And starting from x=0.10, the ground state of this series of compounds is a coexistence of AFM and FM parts. At x=0.30, the AFM order has completely vanished, and only the FM part is left. However, we still observe meta-magnetic transitions at higher temperatures (above 100 K for x=0.30) from the paramagnetic (P) state to a forced FM state. And, of course, such transitions are accompanied by strong magneto-caloric, magnetostrictive, and magnetoresistance effects. The Curie temperatures for the probed compositions going from x=0.05 to x=0.30 were spread over the temperature range of 40 K up to 100 K.Keywords: metamagnetism, RMB intermetallic, magneto-transport effect, metamagnetic transitions
Procedia PDF Downloads 7221467 A Nuclear Negotiation Qualitative Case Study with Force Field Analysis
Authors: Onur Yuksel
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In today’s complex foreign relations between countries, the nuclear enrichment and nuclear weapon have become a threat for all states in the world. There are couple isolated states which have capacity to produce nuclear weapons such as Iran and North Korea. In this article, Iran nuclear negotiation was analyzed in terms of its relations especially with The United States in order to find the important factors that affect the course of the ongoing nuclear negotiation. In this sense, the Force Field Analysis was used by determining and setting forth Driving and Restraining Forces of the nuclear negotiations in order to see the big picture and to develop strategies that may improve the long-term ongoing Iran nuclear negotiations. It is found that Iran nuclear negotiation heavily depends on breaking down the idea of Iran’s supporting terrorist organizations and being more transparent about nuclear and uranium enrichment. Also, it was found that Iran has to rebuild its relations with Western countries, especially with the United States. In addition, the counties— who contribute to Iran nuclear negotiations— will need to work on the dynamics and drivers of the Israel and Iran relations in order to peacefully transform the conflict between the two states.Keywords: driving force, Iran nuclear negotiation, restraining force, the force field analysis
Procedia PDF Downloads 16021466 Peculiarities of Comprehending the Subjective Well-Being by Student with High and Low Level of Emotional Intelligent
Authors: Veronika Pivkina, Alla Kim, Khon Nataliya
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Actuality of the present study is defined first of all the role of subjective well-being problem in modern psychology and the comprehending of subjective well-being by current students. Purpose of this research is to educe peculiarities of comprehending of subjective well-being by students with various levels of emotional intelligent. Methods of research are adapted Russian-Language questionnaire of K. Riff 'The scales of psychological well-being'; emotional intelligent questionnaire of D. V. Lusin. The research involved 72 student from different universities and disciplines aged between 18 and 24. Analyzing the results of the studies, it can be concluded that the understanding of happiness in different groups of students with high and low levels of overall emotional intelligence is different, as well as differentiated by gender. Students with higher level of happiness possess more capacity and higher need to control their emotions, to cause and maintain the desired emotions and control something undesirable.Keywords: subjective well-being, emotional intelligent, psychology of comprehending, students
Procedia PDF Downloads 37721465 Kinetic and Thermodynamic Modified Pectin with Chitosan by Forming Polyelectrolyte Complex Adsorbent to Remediate of Pb(II)
Authors: Budi Hastuti, Mudasir, Dwi Siswanta, Triyono
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Biosorbent, such as pectin and chitosan, are usually produced with low physical stability, thus the materials need to be modified. In this research, the physical characteristic of adsorbent was increased by grafting chitosan using acetate carboxymetyl chitosan (CC). Further, CC and Pectin (Pec) were crosslinked using cross-linking agent BADGE (bis phenol A diglycidyl ether) to get CC-Pec-BADGE (CPB) adsorbent. The cross-linking processes aim to form stable structure and resistance on acidic media. Furthermore, in order to increase the adsorption capacity in removing Pb(II), the adsorbent was added with NaCl to form macroporous adsorbent named CCPec-BADGE-Na (CPB-Na). The physical and chemical characteristics of the porogenic adsorbent structure were characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR). The adsorption parameter of CPB-Na to adsorb Pb(II) ion was determined. The kinetics and thermodynamics of the bath sorption of Pb(II) on CPB-Na adsorbent and using chitosan and pectin as a comparison were also studied. The results showed that the CPB-Na biosorbent was stable on acidic media. It had a rough and porous surface area, increased and gave higher sorption capacity for removal of Pb(II) ion. The CPB-Na 1/1 and 1/3 adsorbent adsorbed Pb(II) with adsorption capacity of 45.48 mg/g and 45.97 mg/g respectively, whereas pectin and chitosan were of 39.20 mg /g and 24.67 mg /g respectively.Keywords: porogen, Pectin, Carboxymethyl Chitosan (CC), CC- Pec-BADGE-Na
Procedia PDF Downloads 16121464 Do Clawback Provisions Increase the Demand for Audit Service?
Authors: Yu-Chun Lin
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This study examines whether the adoption of clawback provisions increases the demand for audit service. We use abnormal audit fees to proxy for the demand for audit service. Because firms’ voluntary adoption of the clawback provisions is endogenously determined, this study controls for this bias using the propensity-score matching technique. Based on 1,247 U.S. firms that voluntarily adopt clawback provisions during 2003-2013 and a matched sample, the empirical results show that clawback provisions adoption is associated with abnormal audit fees, especially by firms with higher likelihood of misstatements. When firm executives are overconfident, abnormal audit fees increase subsequent to clawback provisions adoption. Since regulators require listed firms to adopt recoupment policy after 2015 in U.S., the evidence about higher demand for audit service might provide political implications for mandatory clawback provisions.Keywords: clawback provisions, audit service, audit fees, overconfidence
Procedia PDF Downloads 38421463 Inverse Mode Shape Problem of Hand-Arm Vibration (Humerus Bone) for Bio-Dynamic Response Using Varying Boundary Conditions
Authors: Ajay R, Rammohan B, Sridhar K S S, Gurusharan N
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The objective of the work is to develop a numerical method to solve the inverse mode shape problem by determining the cross-sectional area of a structure for the desired mode shape via the vibration response study of the humerus bone, which is in the form of a cantilever beam with anisotropic material properties. The humerus bone is the long bone in the arm that connects the shoulder to the elbow. The mode shape is assumed to be a higher-order polynomial satisfying a prescribed set of boundary conditions to converge the numerical algorithm. The natural frequency and the mode shapes are calculated for different boundary conditions to find the cross-sectional area of humerus bone from Eigenmode shape with the aid of the inverse mode shape algorithm. The cross-sectional area of humerus bone validates the mode shapes of specific boundary conditions. The numerical method to solve the inverse mode shape problem is validated in the biomedical application by finding the cross-sectional area of a humerus bone in the human arm.Keywords: Cross-sectional area, Humerus bone, Inverse mode shape problem, Mode shape
Procedia PDF Downloads 13021462 Impact of Information and Communication Technology on Achievement of Technical Students and Perspective Teachers: A Study of Haryana State
Authors: Anu Malhotra, Rahul Malhotra
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This review paper is focused on achievement ability analysis of perspective teachers and students of technical education of Haryana. It is well known that women have higher verbal achievement, while men have higher achievement in non-verbal and scientific achievement. Chi-square analyses were performed to evaluate the effect of information and communication technology tools on the scientific, verbal and non-verbal achievement of the controlled and uncontrolled group of 204 students of Haryana. The computed value of expected count, which is more than 5, shows that there is a significant improvement in achievement ability of students of the controlled group when compared to the uncontrolled group. The research analyzes that the Information and communication technology tools play an important role in enhancing student’s achievement.Keywords: achievement, ICT, perspective teacher, verbal achievement
Procedia PDF Downloads 17821461 Elucidation of the Photoreactivity of 2-Hydroxychalcones and the Effect of Continuous Photoflow Method on the Photoreactivity
Authors: Sobiya George, Anna Dora Gudmundsdottir
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The 2-hydroxychalcones form an important group of organic compounds not only because of their pharmacological properties but also because they are intermediates in the biosynthesis of flavanones. We studied the photoreactivity of 2-hydroxychalcone derivatives in aprotic solvent acetonitrile and found that their photochemistry is concentration-dependent. Irradiation of 2-hydroxychalcone derivatives with 365 nm light emitting diode (LED) in dilute concentration selectively forms flavanones, whereas, at higher concentrations, an additional photoproduct is observed. However, the application of the continuous photo-flow method resulted in the selective formation of flavanones even at higher concentrations. To understand the reaction mechanism and explain the concentration-dependent photoreactivity of 2-hydroxychalcones, we preformed trapping studies with tris(trimethylsilyl)silane, nanosecond laser flash photolysis, and time dependent-density functional theory (TD-DFT) calculations.Keywords: flavanones, hydroxychalcones, laser flash photolysis, TD-DFT calculations
Procedia PDF Downloads 15121460 Pattern and Risk Factors of Menstrual Regulation Service Use among Ever-married Women in Bangladesh: Evidence from a Nationally Representative Cross-sectional Study
Authors: Md. Rashed Aalm, Md. Nuruzzaman Khan, Yothin Sawangdee
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Background: Around 47% of the total pregnancies are unintended in Bangladesh, which lead to several adverse consequences, including maternal and child mortality. Use of menstrual regulation (MR) can help women to reduce unintended pregnancy related adverse consequences. We explored the prevalence and determinants of MR services among ever-married women in Bangladesh. Methods: Total of 14,346 ever-married women data were analysed from the 2017 Bangladesh Demographic and Health Survey. Our study variable was use or non-use of MR services. Individual, household, and community level factors were the explanatory factors. Multilevel mixed-effect Poisson regression model was used to determine the factors associated with MR services in Bangladesh. Results: Nearly 7% of the total women in Bangladesh use MR services. Use of MR services was found higher among women who were aged 20-30 ages (IRR 1.60, 95% CI: 1.17–2.17), who were overweight (IRR 1.43, 95% CI: 1.13–1.81), had at least 1 child (IRR 2.97, 95% CI: 2.34– 3.77) or > 2 children (IRR 3.22, 95% CI: 2.45–4.20), and the birth preceding birth interval was(2 – 4) years (IRR 1.56, 95% CI: 1.13–2.15). Around 1.39 times (95% CI: 1.11–1.73) higher likelihood of MR was found among women whose husbands were engage with business. At the community level, MR service was found lower among the women who resided in the community with higherilliteracy (IRR 0.67, 95% CI: 0.42–0.96) and the Mymensingh division (IRR 0.39, 95% CI: 0.31–0.91). Conclusion: Use of MR service is comparatively low, which indicate a significant proportion of unintended pregnancy continued toward life-birth. This could be responsible for higher adverse maternal and child health outcomes in Bangladesh. Initiatives should be taken to ensure MR services is available when women need this service.Keywords: menstrual regulation, pattern, risk, maternal health, Bangladesh
Procedia PDF Downloads 16421459 Evaluation of Teaching Performance in Higher Education: From the Students' Responsibility to Their Evaluative Competence
Authors: Natacha Jesus-Silva, Carla S. Pereira, Natercia Durao, Maria Das Dores Formosinho, Cristina Costa-Lobo
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Any assessment process, by its very nature, raises a wide range of doubts, uncertainties, and insecurities of all kinds. The evaluation process should be ethically irreproachable, treating each and every one of the evaluated according to a conduct that ensures that the process is fair, contributing to all recognize and feel well with the processes and results of the evaluation. This is a very important starting point and implies that positive and constructive conceptions and attitudes are developed regarding the evaluation of teaching performance, where students' responsibility is desired. It is not uncommon to find teachers feeling threatened at various levels, in particular as regards their autonomy and their professional dignity. Evaluation must be useful in that it should enable decisions to be taken to improve teacher performance, the quality of teaching or the learning climate of the school. This study is part of a research project whose main objective is to identify, select, evaluate and synthesize the available evidence on Quality Indicators in Higher Education. In this work, the 01 parameters resulting from pedagogical surveys in a Portuguese higher education institution in the north of the country will be presented, surveys for the 2015/2016 school year, presented to 1751 students, in a total of 11 degrees and 18 master's degrees. It has analyzed the evaluation made by students with respect to the performance of a group of 68 teachers working full time. This paper presents the lessons learned in the last three academic years, allowing for the identification of the effects on the following areas: teaching strategies and methodologies, capacity of systematization, learning climate, creation of conditions for active student participation. This paper describes the procedures resulting from the descriptive analysis (frequency analysis, descriptive measures and association measures) and inferential analysis (ANOVA one-way, MANOVA one-way, MANOVA two-way and correlation analysis).Keywords: teaching performance, higher education, students responsibility, indicators of teaching management
Procedia PDF Downloads 27921458 Transducers for Measuring Displacements of Rotating Blades in Turbomachines
Authors: Pavel Prochazka
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The study deals with transducers for measuring vibration displacements of rotating blade tips in turbomachines. In order to prevent major accidents with extensive economic consequences, it shows an urgent need for every low-pressure steam turbine stage being equipped with modern non-contact measuring system providing information on blade loading, damage and residual lifetime under operation. The requirement of measuring vibration and static characteristics of steam turbine blades, therefore, calls for the development and operational verification of both new types of sensors and measuring principles and methods. The task is really demanding: to measure displacements of blade tips with a resolution of the order of 10 μm by speeds up to 750 m/s, humidity 100% and temperatures up to 200 °C. While in gas turbines are used primarily capacitive and optical transducers, these transducers cannot be used in steam turbines. The reason is moisture vapor, droplets of condensing water and dirt, which disable the function of sensors. Therefore, the most feasible approach was to focus on research of electromagnetic sensors featuring promising characteristics for given blade materials in a steam environment. Following types of sensors have been developed and both experimentally and theoretically studied in the Institute of Thermodynamics, Academy of Sciences of the Czech Republic: eddy-current, Hall effect, inductive and magnetoresistive. Eddy-current transducers demand a small distance of 1 to 2 mm and change properties in the harsh environment of steam turbines. Hall effect sensors have relatively low sensitivity, high values of offset, drift, and especially noise. Induction sensors do not require any supply current and have a simple construction. The magnitude of the sensors output voltage is dependent on the velocity of the measured body and concurrently on the varying magnetic induction, and they cannot be used statically. Magnetoresistive sensors are formed by magnetoresistors arranged into a Wheatstone bridge. Supplying the sensor from a current source provides better linearity. The MR sensors can be used permanently for temperatures up to 200 °C at lower values of the supply current of about 1 mA. The frequency range of 0 to 300 kHz is by an order higher comparing to the Hall effect and induction sensors. The frequency band starts at zero frequency, which is very important because the sensors can be calibrated statically. The MR sensors feature high sensitivity and low noise. The symmetry of the bridge arrangement leads to a high common mode rejection ratio and suppressing disturbances, which is important, especially in industrial applications. The MR sensors feature high sensitivity, high common mode rejection ratio, and low noise, which is important, especially in industrial applications. Magnetoresistive transducers provide a range of excellent properties indicating their priority for displacement measurements of rotating blades in turbomachines.Keywords: turbines, blade vibration, blade tip timing, non-contact sensors, magnetoresistive sensors
Procedia PDF Downloads 13021457 Evaluation of the Boiling Liquid Expanding Vapor Explosion Thermal Effects in Hassi R'Mel Gas Processing Plant Using Fire Dynamics Simulator
Authors: Brady Manescau, Ilyas Sellami, Khaled Chetehouna, Charles De Izarra, Rachid Nait-Said, Fati Zidani
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During a fire in an oil and gas refinery, several thermal accidents can occur and cause serious damage to people and environment. Among these accidents, the BLEVE (Boiling Liquid Expanding Vapor Explosion) is most observed and remains a major concern for risk decision-makers. It corresponds to a violent vaporization of explosive nature following the rupture of a vessel containing a liquid at a temperature significantly higher than its normal boiling point at atmospheric pressure. Their effects on the environment generally appear in three ways: blast overpressure, radiation from the fireball if the liquid involved is flammable and fragment hazards. In order to estimate the potential damage that would be caused by such an explosion, risk decision-makers often use quantitative risk analysis (QRA). This analysis is a rigorous and advanced approach that requires a reliable data in order to obtain a good estimate and control of risks. However, in most cases, the data used in QRA are obtained from the empirical correlations. These empirical correlations generally overestimate BLEVE effects because they are based on simplifications and do not take into account real parameters like the geometry effect. Considering that these risk analyses are based on an assessment of BLEVE effects on human life and plant equipment, more precise and reliable data should be provided. From this point of view, the CFD modeling of BLEVE effects appears as a solution to the empirical law limitations. In this context, the main objective is to develop a numerical tool in order to predict BLEVE thermal effects using the CFD code FDS version 6. Simulations are carried out with a mesh size of 1 m. The fireball source is modeled as a vertical release of hot fuel in a short time. The modeling of fireball dynamics is based on a single step combustion using an EDC model coupled with the default LES turbulence model. Fireball characteristics (diameter, height, heat flux and lifetime) issued from the large scale BAM experiment are used to demonstrate the ability of FDS to simulate the various steps of the BLEVE phenomenon from ignition up to total burnout. The influence of release parameters such as the injection rate and the radiative fraction on the fireball heat flux is also presented. Predictions are very encouraging and show good agreement in comparison with BAM experiment data. In addition, a numerical study is carried out on an operational propane accumulator in an Algerian gas processing plant of SONATRACH company located in the Hassi R’Mel Gas Field (the largest gas field in Algeria).Keywords: BLEVE effects, CFD, FDS, fireball, LES, QRA
Procedia PDF Downloads 18721456 Questionnaire for the Evaluation of Entrepreneurship Project Psychopedagogical Practices: Construction Proceedings and Validation
Authors: Cristina Costa-Lobo, Sandra Fernandes, Miguel Magalhães, José Dinis-Carvalho, Alfredo Regueiro, Ana Carvalho
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This paper is a report on the findings of the construction and the validation of a questionnaire monetized in a portuguese higher education context with undergraduate students. The Questionnaire for the Evaluation of Entrepreneurship Project Psychopedagogical Practices consists of six scales: Critical appraisal of the project, Developed Learning and Skills, Teamwork, Teacher and Tutor Roles, Evaluation of Student Performance, and Project Effectiveness as a Teaching-Learning Methodology. The proceedings of its construction are analyzed, and the validity and internal consistency analysis are described. Findings indicate good indicators of validity, good fidelity and an interpretable factorial structure.Keywords: entrepreneurship project, higher education, psychopedagogical practices, teacher and tutor roles
Procedia PDF Downloads 38321455 Effect of Pressure and Glue Spread on the Bonding Properties of CLT Panels Made from Low-Grade Hardwood
Authors: Sumanta Das, Miroslav Gašparík, Tomáš Kytka, Anil Kumar Sethy
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In this modern century, Cross-laminated timber (CLT) evolved as an excellent material for building and high load-bearing structural applications worldwide. CLT is produced mainly from softwoods such as Norway spruce, White fir, Scots pine, European larch, Douglas fir, and Swiss stone pine. The use of hardwoods in CLT production is still at an early stage, and the utilization of hardwoods is expected to provide the opportunity for obtaining higher bending stiffness and shear resistance to CLT panels. In load-bearing structures like CLT, bonding is an important character that is needed to evaluate. One particular issue with using hardwood lumber in CLT panels is that it is often more challenging to achieve a strong, durable adhesive bond. Several researches in the past years have already evaluated the bonding properties of CLT panels from hardwood both from higher and lower densities. This research aims to identify the effect of pressure and glue spread and evaluate which poplar lumber characteristics affect adhesive bond quality. Three-layered CLT panels were prepared from poplar wood with one-component polyurethane (PUR) adhesive by applying pressure of 0.6 N/mm2 and 1 N/mm2 with a glue spread rate of 160 and 180 g/m2. The delamination and block shear tests were carried out as per EN 16351:2015, and the wood failure percentage was also evaluated. The results revealed that glue spread rate and applied pressure significantly influenced both the shear bond strength and wood failure percentage of the CLT. However, samples with lower pressure 0.6 N/mm2 and less glue spread rate showed delamination, and in samples with higher pressure 1 N/mm2 and higher glue spread rate, no delamination was observed. All the properties determined by this study met the minimum requirement mentioned in EN 16351:2015 standard.Keywords: cross-laminated timber, delamination, glue spread rate, poplar, pressure, PUR, shear strength, wood failure percentage
Procedia PDF Downloads 16521454 Investigation of Processing Conditions on Rheological Features of Emulsion Gels and Oleogels Stabilized by Biopolymers
Authors: M. Sarraf, J. E. Moros, M. C. Sánchez
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Oleogels are self-standing systems that are able to trap edible liquid oil into a tridimensional network and also help to use less fat by forming crystallization oleogelators. There are different ways to generate oleogelation and oil structuring, including direct dispersion, structured biphasic systems, oil sorption, and indirect method (emulsion-template). The selection of processing conditions as well as the composition of the oleogels is essential to obtain a stable oleogel with characteristics suitable for its purpose. In this sense, one of the ingredients widely used in food products to produce oleogels and emulsions is polysaccharides. Basil seed gum (BSG), with the scientific name Ocimum basilicum, is a new native polysaccharide with high viscosity and pseudoplastic behavior because of its high molecular weight in the food industry. Also, proteins can stabilize oil in water due to the presence of amino and carboxyl moieties that result in surface activity. Whey proteins are widely used in the food industry due to available, cheap ingredients, nutritional and functional characteristics such as emulsifier and a gelling agent, thickening, and water-binding capacity. In general, the interaction of protein and polysaccharides has a significant effect on the food structures and their stability, like the texture of dairy products, by controlling the interactions in macromolecular systems. Using edible oleogels as oil structuring helps for targeted delivery of a component trapped in a structural network. Therefore, the development of efficient oleogel is essential in the food industry. A complete understanding of the important points, such as the ratio oil phase, processing conditions, and concentrations of biopolymers that affect the formation and stability of the emulsion, can result in crucial information in the production of a suitable oleogel. In this research, the effects of oil concentration and pressure used in the manufacture of the emulsion prior to obtaining the oleogel have been evaluated through the analysis of droplet size and rheological properties of obtained emulsions and oleogels. The results show that the emulsion prepared in the high-pressure homogenizer (HPH) at higher pressure values has smaller droplet sizes and a higher uniformity in the size distribution curve. On the other hand, in relation to the rheological characteristics of the emulsions and oleogels obtained, the predominantly elastic character of the systems must be noted, as they present values of the storage modulus higher than those of losses, also showing an important plateau zone, typical of structured systems. In the same way, if steady-state viscous flow tests have been analyzed on both emulsions and oleogels, the result is that, once again, the pressure used in the homogenizer is an important factor for obtaining emulsions with adequate droplet size and the subsequent oleogel. Thus, various routes for trapping oil inside a biopolymer matrix with adjustable mechanical properties could be applied for the creation of the three-dimensional network in order to the oil absorption and creating oleogel.Keywords: basil seed gum, particle size, viscoelastic properties, whey protein
Procedia PDF Downloads 6721453 Numerical Investigation of Turbulent Flow Control by Suction and Injection on a Subsonic NACA23012 Airfoil by Proper Orthogonal Decomposition Analysis and Perturbed Reynolds Averaged Navier‐Stokes Equations
Authors: Azam Zare
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Separation flow control for performance enhancement over airfoils at high incidence angle has become an increasingly important topic. This work details the characteristics of an efficient feedback control of the turbulent subsonic flow over NACA23012 airfoil using forced reduced‐order model based on the proper orthogonal decomposition/Galerkin projection and perturbation method on the compressible Reynolds Averaged Navier‐Stokes equations. The forced reduced‐order model is used in the optimal control of the turbulent separated flow over a NACA23012 airfoil at Mach number of 0.2, Reynolds number of 5×106, and high incidence angle of 24° using blowing/suction controlling jets. The Spallart-Almaras turbulence model is implemented for high Reynolds number calculations. The main shortcoming of the POD/Galerkin projection on flow equations for controlling purposes is that the blowing/suction controlling jet velocity does not show up explicitly in the resulting reduced order model. Combining perturbation method and POD/Galerkin projection on flow equations introduce a forced reduced‐order model that can predict the time-varying influence of the blowing/suction controlling jet velocity. An optimal control theory based on forced reduced‐order system is used to design a control law for a nonlinear reduced‐order model, which attempts to minimize the vorticity content in the turbulent flow field over NACA23012 airfoil. Numerical simulations were performed to help understand the behavior of the controlled suction jet at 12% to 18% chord from leading edge and a pair of blowing/suction jets at 15% to 18% and 24% to 30% chord from leading edge, respectively. Analysis of streamline profiles indicates that the blowing/suction jets are efficient in removing separation bubbles and increasing the lift coefficient up to 22%, while the perturbation method can predict the flow field in an accurate Manner.Keywords: flow control, POD, Galerkin projection, separation
Procedia PDF Downloads 15621452 Scope of Samarium Content on Microstructural and Structural Properties of Potassium-Sodium Niobate (KNN) Based Ceramics
Authors: Geraldine Giraldo
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In the research of advanced materials, ceramics based on KNN are an important topic, especially for multifunctional applications. In this work, the physical, structural, and microstructural properties of the (KNN-CaLi-xSm) system were analyzed by varying the concentration of samarium, which was prepared using the conventional solid-state reaction method by mixing oxides. It was found that the increase in Sm+3 concentration led to higher porosity in the sample and, consequently, a decrease in density, which is attributed to the structural vacancies at the A-sites of the perovskite-type structure of the ceramic system. In the structural analysis, a coexistence of Tetragonal (T) and Orthorhombic (O) phases were observed at different rare-earth ion contents, with a higher content of the T phase at xSm=0.010. Furthermore, the structural changes in the calcined powders at different temperatures were studied using the results of DTA-TG, which allowed for the analysis of the system's composition. It was found that the lowest total decomposition temperature occurred when xSm=0.010 at 770°C.Keywords: perovskite, piezoelectric, multifunctional, Structure, ceramic
Procedia PDF Downloads 7221451 An Evaluation on the Methodology of Manufacturing High Performance Organophilic Clay at the Most Efficient and Cost Effective Process
Authors: Siti Nur Izati Azmi, Zatil Afifah Omar, Kathi Swaran, Navin Kumar
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Organophilic Clays, also known as Organoclays, is used as a viscosifier in Oil based Drilling fluids. Most often, Organophilic clay are produced from modified Sodium and Calcium based Bentonite. Many studies and data show that Organophilic Clay using Hectorite based clays provide the best yield and good fluid loss properties in an oil-based drilling fluid at a higher cost. In terms of the manufacturing process, the two common methods of manufacturing organophilic clays are a Wet Process and a Dry Process. Wet process is known to produce better performance product at a higher cost while Dry Process shorten the production time. Hence, the purpose of this study is to evaluate the various formulation of an organophilic clay and its performance vs. the cost, as well as to determine the most efficient and cost-effective method of manufacturing organophilic clays.Keywords: organophilic clay, viscosifier, wet process, dry process
Procedia PDF Downloads 23121450 Salinity Effects on Germination of Malaysian Rice Varieties and Weedy Rice Biotypes
Authors: M. Kamal Uddin, H. Mohd Dandan, Ame H. Alidin
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Germination and seedling growth of plant species are reduced in saline due to an external osmotic potential. An experiment was conducted at the laboratory, Faculty of Sustainable Agriculture, Universiti Malaysia Sabah, to compare the salt effect on seed germination and growth of weedy rice and cultivated rice. Seeds (10 in each) were placed in petri dishes. Five salinity levels 0 (distilled water), 4, 8, 12 and 16 dSm-1 (NaCl) were applied. The number of germinated seeds was recorded daily. The final germination percentage, germination index (GI), seedling vigour index (SVI) mean germination time (MGT), shoot and root dry weight were estimated. At highest salinity (16 dSm-1) germination percentage was higher (100%) in weedy rice awn and weedy rice compact. Lowest germination percentage was in MR219 and TQR-8 (50-60%). Mean germination time (MGT) was found higher in all weedy rice biotypes compared to cultivated rice. At highest salinity (16dSm-1) weedy rice open produced the highest MGT (9.92) followed by weedy rice compact (9.73) while lowest MGT was in MR219 (9.48). At highest salinity (16dSm-1) germination index was higher in weedy rice awn (11.71) and compact type (9.62). Lowest germination index was in MR219 (5.90) and TQR-8 (8.94). At the highest salinity (16 dSm−1), seedling vigor index was highest in weedy rice awn (6.06) followed by weedy rice compact (5.26); while lowest was in MR219 (2.11) followed by MR269 (3.82).On the basis of Germination index, seedling vigor index and growth related results it could be concluded that weedy rice awn, compact and open biotypes were more salt tolerant compared to other cultivated rice MR219, MR269, and TQR-8.Keywords: germination, salinity, rice and weedy rice, sustainable agriculture
Procedia PDF Downloads 49321449 Comparative Analysis of Soil Enzyme Activities between Laurel-Leaved and Cryptomeria japonica Forests
Authors: Ayuko Itsuki, Sachiyo Aburatani
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Soil enzyme activities in Kasuga-yama Hill Primeval Forest (Nara, Japan) were examined to determine levels of mineralization and metabolism. Samples were selected from the soil surrounding laurel-leaved (BB-1) and Carpinus japonica (BB-2 and Pw) trees for analysis. Cellulase, β-xylosidase, and protease activities were higher in BB-1 samples those in BB-2 samples. These activity levels corresponded to the distribution of cellulose and hemicellulose in the soil horizons. Cellulase, β-xylosidase, and chymotrypsin activities were higher in soil from the Pw forest than in that from the BB-2 forest. The relationships between the soil enzymes calculated by Spearman’s rank correlation indicate that the interactions between enzymes in BB-2 samples were more complex than those in Pw samples.Keywords: comparative analysis, enzyme activities, forest soil, Spearman's rank correlation
Procedia PDF Downloads 59621448 Associations between Sleep Problems and Disordered Eating in Japanese Adolescents: A Cross-Sectional Study
Authors: Takaharu Hirai, Yuta Mitobe, Hiromi Hirai
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Introduction: Eating disorders (ED) are serious psychiatric disorders that affect individuals, especially adolescents. It has been suggested that nonclinical ED-like characteristics are related to sleep problems. However, studies exploring the association between potential ED and sleep disorders have primarily been conducted in Europe and the United States. We conducted a survey of Japanese adolescents to investigate this claim. Method: In this cross-sectional study, 398 school-aged adolescents, aged 12–18 years old, matched for gender ratio, responded to a self-administered questionnaire survey. We used the Eating Attitudes Test-26 (EAT-26) and the Athens Insomnia Scale (AIS) to measure potential ED and sleep problems, respectively. In this study, participants with an EAT-26 total score of 0–19 points were classified as non-ED, while those with scores of 20 points or higher were classified as potential ED. Result: Of the 398 participants, 17 (4.3%) had an EAT-26 total score of 20 or higher. Among boys, the rate was 6 of 199 participants (3%), and among girls, the rate was 11 of 182 participants (6%). There were 89 participants (22.4%) with an AIS score of 6 points or higher, of which 36 (17.6%) were boys, and 53 (27.5%) were girls. Adolescents with potential ED had significantly higher rates of daytime sleep problems than those without ED. Further, while examining the types of sleep problems, adolescents with potential ED had greater problems with a sense of well-being and physical and mental functioning during the day. In contrast, no significant associations were found between potential ED and sleep initiation, awakenings during the night, early morning awakening, total sleep duration, or overall quality of sleep. Finally, nocturnal and daytime sleep scores were significantly associated with dieting, bulimia, and oral control EAT-26 sub-scores. Discussion: While Japanese adolescents with possible ED do not experience nighttime sleep problems, they do experience problems related to well-being and mental and physical functioning, which are indicators of daytime sleep problems. This may assist with early detection of disordered eating in adolescents. The study suggested that professionals working towards adolescent mental health issues need an approach that comprehensively integrates both sleep problems and potential ED.Keywords: adolescents, potential eating disorders, sleep problems, eating attitudes test-26
Procedia PDF Downloads 17721447 Musculoskeletal Pain, Work Characteristics and Presenteeism among Hotel Employees
Authors: Ruey-Yu Chen, Yao-Tsung Chang, Ching-Ying Yeh, Yu-Ting Huang
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Musculoskeletal problems in the hotel sector have been little studied. The aim of this study was to examine relationships of musculoskeletal pain and work characteristics with presenteeism, i.e., feeling sick but going to work anyway. Data of a self-reported questionnaire were collected from 1,101 employees, who joined the study on a voluntary basis from four hotels in northern Taiwan. The results showed that respondents who were female, were younger, had a higher educational level, and worked in the real-service department had higher presenteeism. There were significant positive associations between presenteeism and heavy loads, frequent beatings or hits of hard objects, improper bench height, employees’ lower limb and lower back pain. Our study results imply that knowledge of work characteristics and employees' musculoskeletal problems could be advantageously used to reduce presenteeism in the workplace.Keywords: musculoskeletal pain, absenteeism, presenteeism, hotel employees
Procedia PDF Downloads 19721446 Carcinogenic Polycyclic Aromatic Hydrocarbons in Urban Air Particulate Matter
Authors: A. Szabó Nagy, J. Szabó, Zs. Csanádi, J. Erdős
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An assessment of the air quality of Győr (Hungary) was performed by determining the ambient concentrations of PM10-bound carcinogenic polycyclic aromatic hydrocarbons (cPAHs) in different seasons. A high volume sampler was used for the collection of ambient aerosol particles, and the associated cPAH compounds (benzo[a]pyrene (BaP), benzo[a]anthracene, benzofluoranthene isomers, indeno[123-cd]pyrene and dibenzo[ah]anthracene) were analyzed by a gas chromatographic method. Higher mean concentrations of total cPAHs were detected in samples collected in winter (9.62 ng/m3) and autumn (2.69 ng/m3) compared to spring (1.05 ng/m3) and summer (0.21 ng/m3). The calculated BaP toxic equivalent concentrations have also reflected that the local population appears to be exposed to significantly higher cancer risk in the heating seasons. Moreover, the concentration levels of cPAHs determined in this study were compared to other Hungarian urban sites.Keywords: air, carcinogenic, polycyclic aromatic hydrocarbons (PAH), PM10
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