Search results for: Philippine folk literature
1450 Evaluating the Performance of Passive Direct Methanol Fuel Cell under Varying Operating and Structural Conditions
Authors: Rahul Saraswat
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More recently, a focus has been given to replacing machined stainless steel metal flow fields with inexpensive wire mesh current collectors. The flow fields are based on simple woven wire mesh screens of various stainless steels, which are sandwiched between a thin metal plate of the same material to create a bipolar plate/flow field configuration for use in a stack. Major advantages of using stainless steel wire screens include the elimination of expensive raw materials as well as machining and/or other special fabrication costs. The objective of the project is to improve the performance of the passive direct methanol fuel cell without increasing the cost of the cell and to make it as compact and light as possible. From the literature survey, it was found that very little is done in this direction, and the following methodology was used. 1. The passive direct methanol fuel cell (DMFC) can be made more compact, lighter, and less costly by changing the material used in its construction. 2. Controlling the fuel diffusion rate through the cell improves the performance of the cell. A passive liquid feed direct methanol fuel cell (DMFC) was fabricated using a given MEA (Membrane Electrode Assembly) and tested for different current collector structures. Mesh current collectors of different mesh densities along with different support structures, were used, and the performance was found to be better. Methanol concentration was also varied. Optimisation of mesh size, support structure, and fuel concentration was achieved. Cost analysis was also performed hereby. From the performance analysis study of DMFC, we can conclude with the following points: Area specific resistance (ASR) of wire mesh current collectors is lower than the ASR of stainless steel current collectors. Also, the power produced by wire mesh current collectors is always more than that produced by stainless steel current collectors. 1. Low or moderate methanol concentrations should be used for better and stable DMFC performance. 2. Wiremesh is a good substitute for stainless steel for current collector plates of passive DMFC because of its lower cost (by about 27 %), flexibility, and light in weight characteristics of wire mesh.Keywords: direct methanol fuel cell, membrane electrode assembly, mesh, mesh size, methanol concentration, support structure
Procedia PDF Downloads 801449 Anxiety and Self-Perceived L2 Proficiency: A Comparison of Which Can Better Predict L2 Pronunciation Performance
Authors: Jiexuan Lin, Huiyi Chen
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The development of L2 pronunciation competence remains understudied in the literature and it is not clear what may influence learners’ development of L2 pronunciation. The present study was an attempt to find out which of the two common factors in L2 acquisition, i.e., foreign language anxiety or self-perceived L2 proficiency, can better predict Chinese EFL learners’ pronunciation performance. 78 first-year English majors, who had received a three-month pronunciation training course, were asked to 1) fill out a questionnaire on foreign language classroom anxiety, 2) self-report their L2 proficiency in general, in speaking and in pronunciation, and 3) complete an oral and a written test on their L2 pronunciation (the score of the oral part indicates participants’ pronunciation proficiency in oral production, and the score of the written part indexes participants’ ability in applying pronunciation knowledge in comprehension.) Results showed that the pronunciation scores were negatively correlated with the anxiety scores, and were positively correlated with the self-perceived pronunciation proficiency. But only the written scores in the L2 pronunciation test, not the oral scores, were positively correlated with the L2 self-perceived general proficiency. Neither the oral nor the written scores in the L2 pronunciation test had a significant correlation with the self-perceived speaking proficiency. Given the fairly strong correlations, the anxiety scores and the self-perceived pronunciation proficiency were put in regression models to predict L2 pronunciation performance. The anxiety factor alone accounted for 13.9% of the variance and the self-perceived pronunciation proficiency alone explained 12.1% of the variance. But when both anxiety scores and self-perceived pronunciation proficiency were put in a stepwise regression model, only the anxiety scores had a significant and unique contribution to the L2 pronunciation performance (4.8%). Taken together, the results suggested that the learners’ anxiety level could better predict their L2 pronunciation performance, compared with the self-perceived proficiency levels. The obtained data have the following pedagogical implications. 1) Given the fairly strong correlation between anxiety and L2 pronunciation performance, the instructors who are interested in predicting learners’ L2 pronunciation proficiency may measure their anxiety level, instead of their proficiency, as the predicting variable. 2) The correlation of oral scores (in the pronunciation test) with pronunciation proficiency, rather than with speaking proficiency, indicates that a) learners after receiving some amounts of training are to some extent able to evaluate their own pronunciation ability, implying the feasibility of incorporating self-evaluation and peer comments in course instruction; b) the ‘proficiency’ measure used to predict pronunciation performance should be used with caution. The proficiency of specific skills seemingly highly related to pronunciation (i.e., speaking in this case) may not be taken for granted as an effective predictor for pronunciation performance. 3) The correlation between the written scores with general L2 proficiency is interesting.Keywords: anxiety, Chinese EFL learners, L2 pronunciation, self-perceived L2 proficiency
Procedia PDF Downloads 3621448 Rheometer Enabled Study of Tissue/biomaterial Frequency-Dependent Properties
Authors: Polina Prokopovich
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Despite the well-established dependence of cartilage mechanical properties on the frequency of the applied load, most research in the field is carried out in either load-free or constant load conditions because of the complexity of the equipment required for the determination of time-dependent properties. These simpler analyses provide a limited representation of cartilage properties thus greatly reducing the impact of the information gathered hindering the understanding of the mechanisms involved in this tissue replacement, development and pathology. More complex techniques could represent better investigative methods, but their uptake in cartilage research is limited by the highly specialised training required and cost of the equipment. There is, therefore, a clear need for alternative experimental approaches to cartilage testing to be deployed in research and clinical settings using more user-friendly and financial accessible devices. Frequency dependent material properties can be determined through rheometry that is an easy to use requiring a relatively inexpensive device; we present how a commercial rheometer can be adapted to determine the viscoelastic properties of articular cartilage. Frequency-sweep tests were run at various applied normal loads on immature, mature and trypsinased (as model of osteoarthritis) cartilage samples to determine the dynamic shear moduli (G*, G′ G″) of the tissues. Moduli increased with increasing frequency and applied load; mature cartilage had generally the highest moduli and GAG depleted samples the lowest. Hydraulic permeability (KH) was estimated from the rheological data and decreased with applied load; GAG depleted cartilage exhibited higher hydraulic permeability than either immature or mature tissues. The rheometer-based methodology developed was validated by the close comparison of the rheometer-obtained cartilage characteristics (G*, G′, G″, KH) with results obtained with more complex testing techniques available in literature. Rheometry is relatively simpler and does not require highly capital intensive machinery and staff training is more accessible; thus the use of a rheometer would represent a cost-effective approach for the determination of frequency-dependent properties of cartilage for more comprehensive and impactful results for both healthcare professional and R&D.Keywords: tissue, rheometer, biomaterial, cartilage
Procedia PDF Downloads 811447 Protection of Patients and Staff in External Beam Radiotherapy Using Linac in Kenya
Authors: Calvince Okome Odeny
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There is a current action to increase radiotherapy services in Kenya. The National government of Kenya, in collaboration with the county governments, has embarked on building radiotherapy centers in all 47 regions of the country. As these new centers are established in Kenya, it has to be ensured that minimum radiation safety standards are in place prior to operation. For full implementation of this, it is imperative that more Research and training for regulators are done on radiation protection, and safety and national regulatory infrastructure is geared towards ensuring radiation protection and safety in all aspects of the use of external radiotherapy practices. The present work aims at reviewing the level of protection and safety for patients and staff during external beam radiotherapy using Linac in Kenya and provides relevant guidance to improve protection and safety. A retrospective evaluation was done to verify whether those occupationally exposed workers and patients are adequately protected from the harmful effect of radiation exposure during the treatment procedures using Linac. The project was experimental Research, also including an analysis of resource documents obtained from the literature and international organizations. The critical findings of the work revealed that the key elements of protection of occupationally exposed workers and patients include a comprehensive quality Management system governing all planned activities from siting, safety, and design of the Facility, construction, acceptance testing, commissioning, operation, and decommissioning of the Facility; Government empowering the Regulatory Authority to license Medical Linear facilities and to enforce the applicable regulations to ensure adequate protection; A comprehensive Radiation Protection and Safety program must be established to ensure adequate safety and protection of workers and patients during treatment planning and treatment delivery of patients and categories of staff associated with the Facility must be well educated and trained to perform professionally with a commitment to sound safety culture. Relevant recommendations from the findings are shared with the Medical Linear Accelerator facilities and the regulatory authority to provide guidance and continuous improvement of protection and safety to improve regulatory oversight.Keywords: oncology, radiotherapy, protection, staff
Procedia PDF Downloads 751446 Institutional Quality and Tax Compliance: A Cross-Country Regression Evidence
Authors: Debi Konukcu Onal, Tarkan Cavusoglu
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In modern societies, the costs of public goods and services are shared through taxes paid by citizens. However, taxation has always been a frictional issue, as tax obligations are perceived to be a financial burden for taxpayers rather than being merit that fulfills the redistribution, regulation and stabilization functions of the welfare state. The tax compliance literature evolves into discussing why people still pay taxes in systems with low costs of legal enforcement. Related empirical and theoretical works show that a wide range of socially oriented behavioral factors can stimulate voluntary compliance and subversive effects as well. These behavioral motivations are argued to be driven by self-enforcing rules of informal institutions, either independently or through interactions with legal orders set by formal institutions. The main focus of this study is to investigate empirically whether institutional particularities have a significant role in explaining the cross-country differences in the tax noncompliance levels. A part of the controversy about the driving forces behind tax noncompliance may be attributed to the lack of empirical evidence. Thus, this study aims to fill this gap through regression estimates, which help to trace the link between institutional quality and noncompliance on a cross-country basis. Tax evasion estimates of Buehn and Schneider is used as the proxy measure for the tax noncompliance levels. Institutional quality is quantified by three different indicators (percentile ranks of Worldwide Governance Indicators, ratings of the International Country Risk Guide, and the country ratings of the Freedom in the World). Robust Least Squares and Threshold Regression estimates based on the sample of the Organization for Economic Co-operation and Development (OECD) countries imply that tax compliance increases with institutional quality. Moreover, a threshold-based asymmetry is detected in the effect of institutional quality on tax noncompliance. That is, the negative effects of tax burdens on compliance are found to be more pronounced in countries with institutional quality below a certain threshold. These findings are robust to all alternative indicators of institutional quality, supporting the significant interaction of societal values with the individual taxpayer decisions.Keywords: institutional quality, OECD economies, tax compliance, tax evasion
Procedia PDF Downloads 1341445 An Exploratory Study of Entrepreneurial Satisfaction among Older Founders
Authors: Catarina Seco Matos, Miguel Amaral
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The developed world is facing falling birth rates and rising life expectancies. As a result, the overall demographic structure of societies is becoming markedly older. This leads to an economic and political pressure towards the extension of individuals’ working lives. On the other hand, evidence shows that some older workers choose to stay in the labour force as employees, whereas others choose to pursue a more entrepreneurial occupational path. Thus, entrepreneurship or self-employment may be an option for socioeconomic participation of older individuals. Previous research on senior entrepreneurship is scarce and it focuses mainly on entrepreneurship determinants and individuals’ intentions. The fact that entrepreneurship is perceived as a voluntary or involuntary decision or as a positive or a negative outcome by older individuals is, to the best of our knowledge, still unexplored in the literature. In order to analyse the determinants of entrepreneurial satisfaction among older individuals, primary data were obtained from a unique questionnaire survey, which was sent to Portuguese senior entrepreneurs who have launched their company aged 50 and over (N=181). Portugal is one of the countries in the world with the with the largest ageing population and with a high proportion of older individuals who remain active after their official retirement age – which makes it an extremely relevant case study on senior entrepreneurship. Findings suggest that non pecuniary factors (rather than pecuniary) are the main driver for entrepreneurship at older ages. Specifically, results show that the will to remain active is the main motivation of older individuals to become entrepreneurs. This is line with the activity and continuity theories. Furthermore, senior entrepreneurs tend to have had an active working life (using their professional experience as a proxy) and, thus, want to keep the same lifestyle at an older age (in line with theory of continuity). Finally, results show that even though older individuals’ companies may not show the best financial performance that does not seem to affect their satisfaction with the company and with entrepreneurship in general. The present study aims at exploring, discussing and bring new research on senior entrepreneurship to the fore, rather than assuming purely deductive approach; hence, further confirmatory analyses with larger sets from different countries of data are required.Keywords: active ageing, entrepreneurship, older entrepreneur, Portugal, satisfaction, senior entrepreneur
Procedia PDF Downloads 2371444 Mobile Marketing Adoption in Pakistan
Authors: Manzoor Ahmad
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The rapid advancement of mobile technology has transformed the way businesses engage with consumers, making mobile marketing a crucial strategy for organizations worldwide. This paper presents a comprehensive study on the adoption of mobile marketing in Pakistan, aiming to provide valuable insights into the current landscape, challenges, and opportunities in this emerging market. To achieve this objective, a mixed-methods approach was employed, combining quantitative surveys and qualitative interviews with industry experts, marketers, and consumers. The study encompassed a diverse range of sectors, including retail, telecommunications, banking, and e-commerce, ensuring a comprehensive understanding of mobile marketing practices across different industries. The findings indicate that mobile marketing has gained significant traction in Pakistan, with a growing number of organizations recognizing its potential for reaching and engaging with consumers effectively. Factors such as increasing smartphone penetration, affordable data plans, and the rise of social media usage have contributed to the widespread adoption of mobile marketing strategies. However, several challenges and barriers to mobile marketing adoption were identified. These include issues related to data privacy and security, limited digital literacy among consumers, inadequate infrastructure, and cultural considerations. Additionally, the study highlights the need for tailored and localized mobile marketing strategies to address the diverse cultural and linguistic landscape of Pakistan. Based on the insights gained from the study, practical recommendations are provided to support organizations in optimizing their mobile marketing efforts in Pakistan. These recommendations encompass areas such as consumer targeting, content localization, mobile app development, personalized messaging, and measurement of mobile marketing effectiveness. This research contributes to the existing literature on mobile marketing adoption in developing countries and specifically sheds light on the unique dynamics of the Pakistani market. It serves as a valuable resource for marketers, practitioners, and policymakers seeking to leverage mobile marketing strategies in Pakistan, ultimately fostering the growth and success of businesses operating in this region.Keywords: mobile marketing, digital marketing, mobile advertising, adoption of mobile marketing
Procedia PDF Downloads 1091443 Effect of Simulation on Anxiety and Knowledge among Novice Nursing Students
Authors: Suja Karkada, Jayanthi Radhakrishnan, Jansi Natarajan, Gerald, Amandu Matua, Sujatha Shanmugasundaram
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Simulation-based learning is an educational strategy designed to simulate actual clinical situations in a safe environment. Globally, simulation is recognized by several landmark studies as an effective teaching-learning method. A systematic review of the literature on simulation revealed simulation as a useful strategy in creating a learning environment which contributes to knowledge, skills, safety, and confidence. However, to the best of the author's knowledge, there are no studies on assessing the anxiety of the students undergoing simulation. Hence the researchers undertook a study with the aim to evaluate the effectiveness of simulation on anxiety and knowledge among novice nursing students. This quasi-experimental study had a total sample of 69 students (35- Intervention group with simulation and 34- Control group with case scenario) consisting of all the students enrolled in the Fundamentals of Nursing Laboratory course during Spring 2016 and Fall 2016 semesters at a college of nursing in Oman. Ethical clearance was obtained from the Institutional Review Board (IRB) of the college of nursing. Informed consent was obtained from every participant. Study received the Dean’s fund for research. The data were collected regarding the demographic information, knowledge and anxiety levels before and after the use of simulation and case scenario for the procedure nasogastric tube feeding in intervention and control group respectively. The intervention was performed by four faculties who were the core team members of the course. Results were analyzed in SPSS using descriptive and inferential statistics. Majority of the students’ in intervention (82.9%) and control (89.9%) groups were equal to or below the age of 20 years, were females (71%), 76.8% of them were from rural areas and 65.2% had a GPA of more than 2.5. The selection of the samples to either the experimental or the control group was from a homogenous population (p > 0.05). There was a significant reduction of anxiety among the students of control group (t (67) = 2.418, p = 0.018) comparing to the experimental group, indicating that simulation creates anxiety among Novice nursing students. However, there was no significant difference in the mean scores of knowledge. In conclusion, the study was useful in that it will help the investigators better understand the implications of using simulation in teaching skills to novice students. Since previous studies with students indicate better knowledge acquisition; this study revealed that simulation can increase anxiety among novice students possibly it is the first time they are introduced to this method of teaching.Keywords: anxiety, knowledge, novice students, simulation
Procedia PDF Downloads 1591442 Knowledge, Attitudes and Practices of Female Students regarding Emergency Contraception at Midlands State University, Zimbabwe
Authors: P. Mambanga, T. G. Tshitangano, H. Akinsola
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Background: Unintended pregnancies constitute a most serious public health challenge to women to an extent that they sometimes end in illegal abortions resulting in adverse consequences. However, the introduction of emergency contraception has served as the last chance for women to avoid unintended pregnancies, though, in countries like Zimbabwe the cause for underutilisation of emergency contraception has been hardly investigated. Purpose: The main purpose of this study was to assess the knowledge, attitude and practice of female students regarding emergency contraception among in preventing unintended pregnancy. Methodology: A quantitative approach using descriptive cross-sectional survey design was conducted among 319 stratified random sampled female university students of Midland State University, Zimbabwe. Self-administered close-ended questionnaire was used to collect the data. To ensure validity, the development of the instrument was guided by a wide range of literature and the inputs of experts. The instrument was retested for reliability and the responses will be comparing using Cronbach’s alpha which yielded high reliability alpha (α) value of 0.84. Data was coded and entered into a computer using Microsoft Excel 2010 and analysed using Statistical Package for Social Scientists (SPSS) version 22.0. Descriptive statistics were used to analyse data in the form of cross tabulation and the results were presented in table, graphs and pie charts. Results: The results indicated that apart from all sources of information about EC, mass media has shown to be the most famous. Although female students knows about EC, the knowledge about effective level and correct use of EC poor. The attitudes of female students at MSU are unfavourable for EC as they gave reasons like EC promotes promiscuity and it can pose risk. The practice of EC at MSU is low with only 47% of respondents said they have once use EC. Conclusion and recommendation: The study concluded the lack of actual knowledge about EC which has directly influenced attitudes and practices. The study concluded that there MSU female students has fair knowledge about EC which has resulted in negative and attitudes towards EC with few EC practices. The study, therefore, recommends the adoption and use of Health Belief Model approach in promoting the young to use EC to prevent unwanted pregnancies.Keywords: emergency contraception, knowledge, attitude, practice, female students
Procedia PDF Downloads 2331441 Improving the Competency of Undergraduate Nursing Students in Addressing a Timely Public Health Issue
Authors: Tsu-Yin Wu, Jenni Hoffman, Lydia McMurrows, Sarah Lally
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Recent events of the Flint Water Crisis and elevated lead levels in Detroit public school water have highlighted a specific public health disparity and shown the need for better education of healthcare providers on lead education. Identifying children and pregnant women with a high risk for lead poisoning and ensuring lead testing is completed is critical. The purpose of this study is to explore the impact of an educational intervention on knowledge and confidence levels among nursing students enrolled in the prelicensure Bachelor of Science in Nursing (BSN) and Registered Nurse to BSN program (R2B). The study used both quantitative and qualitative research methods to assess the impact of multi-modal pedagogy on knowledge and confidence of lead screening and prevention among prelicensure and R2B nursing students. The students received lead poisoning and prevention content in addition to completing an e-learning module developed by the Pediatric Environmental Health Specialty Units. A total of 115 students completed the pre-and post-test instrument that consisted of demographic, lead knowledge, and confidence items. Despite the increase of total knowledge, three dimensions of lead poisoning, and confidence from pre- to post-test scores for both groups, there was no statistical significance on the increase between prelicensure and R2B students. Thematic analysis of qualitative data showed five themes from participants' learning experiences: lead exposure, signs and symptoms of lead poisoning, screening and diagnosis, prevention, and policy and statewide issues. The study is limited by a small sample and participants recalling some correct answers from the pretest, thus, scoring higher on the post-test. The results contribute to the minimally existent literature examining a critical public health concern regarding lead health exposure and prevention education of nursing students. Incorporating such content area into the nursing curriculum is essential in ensuring that such public health disparities are mitigated.Keywords: lead poisoning, emerging public health issue, community health, nursing edducation
Procedia PDF Downloads 1961440 Challenging the Standard 24 Equal Quarter Tones Theory in Arab Music: A Case Study of Tetrachords Bayyātī and ḤIjāz
Authors: Nabil Shair
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Arab music maqām (Arab modal framework) is founded, among other main characteristics, on microtonal intervals. Notwithstanding the importance and multifaceted nature of intonation in Arab music, there is a paucity of studies examining this subject based on scientific and quantitative approaches. The present-day theory concerning the Arab tone system is largely based on the pioneering treatise of Mīkhā’īl Mashāqah (1840), which proposes the theoretical division of the octave into 24 equal quarter tones. This kind of equal-tempered division is incompatible with the performance practice of Arab music, as many professional Arab musicians conceptualize additional pitches beyond the standard 24 notes per octave. In this paper, we refute the standard theory presenting the scale of well-tempered quarter tones by implementing a quantitative analysis of the performed intonation of two prominent tetrachords in Arab music, namely bayyātī and ḥijāz. This analysis was conducted with the help of advanced computer programs, such as Sonic Visualiser and Tony, by which we were able to obtain precise frequency data (Hz) of each tone every 0.01 second. As a result, the value (in cents) of all three intervals of each tetrachord was measured and accordingly compared to the theoretical intervals. As a result, a specific distribution of a range of deviation from the equal-tempered division of the octave was detected, especially the detection of a diminished first interval of bayyātí and diminished second interval of ḥijāz. These types of intonation entail a considerable amount of flexibility, mainly influenced by surrounding tones, direction and function of the measured tone, ornaments, text, personal style of the performer and interaction with the audience. This paper seeks to contribute to the existing literature dealing with intonation in Arab music, as it is a vital part of the performance practice of this musical tradition. In addition, the insights offered by this paper and its novel methodology might also contribute to the broadening of the existing pedagogic methods used to teach Arab music.Keywords: Arab music, intonation, performance practice, music theory, oral music, octave division, tetrachords, music of the middle east, music history, musical intervals
Procedia PDF Downloads 531439 Effect of Different Ground Motion Scaling Methods on Behavior of 40 Story RC Core Wall Building
Authors: Muhammad Usman, Munir Ahmed
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The demand of high-rise buildings has grown fast during the past decades. The design of these buildings by using RC core wall have been widespread nowadays in many countries. The RC core wall (RCCW) buildings encompasses central core wall and boundary columns joined through post tension slab at different floor levels. The core wall often provides greater stiffness as compared to the collective stiffness of the boundary columns. Hence, the core wall dominantly resists lateral loading i.e. wind or earthquake load. Non-linear response history analysis (NLRHA) procedure is the finest seismic design procedure of the times for designing high-rise buildings. The modern design tools for nonlinear response history analysis and performance based design has provided more confidence to design these structures for high-rise buildings. NLRHA requires selection and scaling of ground motions to match design spectrum for site specific conditions. Designers use several techniques for scaling ground motion records (time series). Time domain and frequency domain scaling are most commonly used which comprises their own benefits and drawbacks. Due to lengthy process of NLRHA, application of only one technique is conceivable. To the best of author’s knowledge, no consensus on the best procedures for the selection and scaling of the ground motions is available in literature. This research aims to provide the finest ground motion scaling technique specifically for designing 40 story high-rise RCCW buildings. Seismic response of 40 story RCCW building is checked by applying both the frequency domain and time domain scaling. Variable sites are selected in three critical seismic zones of Pakistan. The results indicates that there is extensive variation in seismic response of building for these scaling. There is still a need to build a consensus on the subjected research by investigating variable sites and buildings heights.Keywords: 40-storied RC core wall building, nonlinear response history analysis, ground motions, time domain scaling, frequency domain scaling
Procedia PDF Downloads 1311438 Experimental Study and Numerical Modelling of Failure of Rocks Typical for Kuzbass Coal Basin
Authors: Mikhail O. Eremin
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Present work is devoted to experimental study and numerical modelling of failure of rocks typical for Kuzbass coal basin (Russia). The main goal was to define strength and deformation characteristics of rocks on the base of uniaxial compression and three-point bending loadings and then to build a mathematical model of failure process for both types of loading. Depending on particular physical-mechanical characteristics typical rocks of Kuzbass coal basin (sandstones, siltstones, mudstones, etc. of different series – Kolchuginsk, Tarbagansk, Balohonsk) manifest brittle and quasi-brittle character of failure. The strength characteristics for both tension and compression are found. Other characteristics are also found from the experiment or taken from literature reviews. On the base of obtained characteristics and structure (obtained from microscopy) the mathematical and structural models are built and numerical modelling of failure under different types of loading is carried out. Effective characteristics obtained from modelling and character of failure correspond to experiment and thus, the mathematical model was verified. An Instron 1185 machine was used to carry out the experiments. Mathematical model includes fundamental conservation laws of solid mechanics – mass, impulse, energy. Each rock has a sufficiently anisotropic structure, however, each crystallite might be considered as isotropic and then a whole rock model has a quasi-isotropic structure. This idea gives an opportunity to use the Hooke’s law inside of each crystallite and thus explicitly accounting for the anisotropy of rocks and the stress-strain state at loading. Inelastic behavior is described in frameworks of two different models: von Mises yield criterion and modified Drucker-Prager yield criterion. The damage accumulation theory is also implemented in order to describe a failure process. Obtained effective characteristics of rocks are used then for modelling of rock mass evolution when mining is carried out both by an open-pit or underground opening.Keywords: damage accumulation, Drucker-Prager yield criterion, failure, mathematical modelling, three-point bending, uniaxial compression
Procedia PDF Downloads 1751437 Numerical Study Pile Installation Disturbance Zone Effects on Excess Pore Pressure Dissipation
Authors: Kang Liu, Meng Liu, Meng-Long Wu, Da-Chang Yue, Hong-Yi Pan
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The soil setup is an important factor affecting pile bearing capacity; there are many factors that influence it, all of which are closely related to pile construction disturbances. During pile installation in soil, a significant amount of excess pore pressure is generated, creating disturbance zones around the pile. The dissipation rate of excess pore pressure is an important factor influencing the pile setup. The paper aims to examine how alterations in parameters within disturbance zones affect the dissipation of excess pore pressure. An axisymmetric FE model is used to simulate pile installation in clay, subsequently consolidation using Plaxis 3D. The influence of disturbed zone on setup is verified, by comparing the parametric studies in uniform field and non-uniform field. Three types of consolidation are employed: consolidation in three directions, vertical consolidation, horizontal consolidation. The results of the parametric study show that the permeability coefficient decreases, soil stiffness decreases, and reference pressure increases in the disturbance zone, resulting in an increase in the dissipation time of excess pore pressure and exhibiting a noticeable threshold phenomenon, which has been commonly overlooked in previous literature. The research in this paper suggests that significant thresholds occur when the coefficient of permeability decreases to half of the original site's value for three-directional and horizontal consolidation within the disturbed zone. Similarly, the threshold for vertical consolidation is observed when the coefficient of permeability decreases to one-fourth of the original site's value. Especially in pile setup research, consolidation is assumed to be horizontal; the study findings suggest that horizontal consolidation has experienced notable alterations as a result of the presence of disturbed zones. Furthermore, the selection of pile installation methods proves to be critical. A nonlinearity excess pore pressure formula is proposed based on cavity expansion theory, which includes the distribution of soil profile modulus with depth.Keywords: pile setup, threshold value effect, installation effects, uniform field, non-uniform field
Procedia PDF Downloads 471436 Effect of Proteoliposome Concentration on Salt Rejection Rate of Polysulfone Membrane Prepared by Incorporation of Escherichia coli and Halomonas elongata Aquaporins
Authors: Aysenur Ozturk, Aysen Yildiz, Hilal Yilmaz, Pinar Ergenekon, Melek Ozkan
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Water scarcity is one of the most important environmental problems of the World today. Desalination process is regarded as a promising solution to solve drinking water problem of the countries facing with water shortages. Reverse osmosis membranes are widely used for desalination processes. Nano structured biomimetic membrane production is one of the most challenging research subject for improving water filtration efficiency of the membranes and for reducing the cost of desalination processes. There are several researches in the literature on the development of novel biomimetic nanofiltration membranes by incorporation of aquaporin Z molecules. Aquaporins are cell membrane proteins that allow the passage of water molecules and reject all other dissolved solutes. They are present in cell membranes of most of the living organisms and provide high water passage capacity. In this study, GST (Glutathione S-transferas) tagged E. coli aquaporinZ and H. elongate aquaporin proteins, which were previously cloned and characterized, were purified from E. coli BL21 cells and used for fabrication of modified Polysulphone Membrane (PS). Aquaporins were incorporated on the surface of the membrane by using 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) phospolipids as carrier liposomes. Aquaporin containing proteoliposomes were immobilized on the surface of the membrane with m-phenylene-diamine (MPD) and trimesoyl chloride (TMC) rejection layer. Water flux, salt rejection and glucose rejection performances of the thin film composite membranes were tested by using Dead-End Reactor Cell. In this study, effect of proteoliposome concentration, and filtration pressure on water flux and salt rejection rate of membranes were investigated. Type of aquaporin used for membrane fabrication, flux and pressure applied for filtration were found to be important parameters affecting rejection rates. Results suggested that optimization of concentration of aquaporin carriers (proteoliposomes) on the membrane surface is necessary for fabrication of effective composite membranes used for different purposes.Keywords: aquaporins, biomimmetic membranes, desalination, water treatment
Procedia PDF Downloads 1981435 Design, Construction and Evaluation of a Mechanical Vapor Compression Distillation System for Wastewater Treatment in a Poultry Company
Authors: Juan S. Vera, Miguel A. Gomez, Omar Gelvez
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Water is Earth's most valuable resource, and the lack of it is currently a critical problem in today’s society. Non-treated wastewaters contribute to this situation, especially those coming from industrial activities, as they reduce the quality of the water bodies, annihilating all kind of life and bringing disease to people in contact with them. An effective solution for this problem is distillation, which removes most contaminants. However, this approach must also be energetically efficient in order to appeal to the industry. In this endeavour, most water distillation treatments fail, with the exception of the Mechanical Vapor Compression (MVC) distillation system, which has a great efficiency due to energy input by a compressor and the latent heat exchange. This paper presents the process of design, construction, and evaluation of a Mechanical Vapor Compression (MVC) distillation system for the main Colombian poultry company Avidesa Macpollo SA. The system will be located in the principal slaughterhouse in the state of Santander, and it will work along with the Gas Energy Mixing system (GEM) to treat the wastewaters from the plant. The main goal of the MVC distiller, rarely used in this type of application, is to reduce the chlorides, Chemical Oxygen Demand (COD) and Biological Oxygen Demand (BOD) levels according to the state regulations since the GEM cannot decrease them enough. The MVC distillation system works with three components, the evaporator/condenser heat exchanger where the distillation takes place, a low-pressure compressor which gives the energy to create the temperature differential between the evaporator and condenser cavities and a preheater to save the remaining energy in the distillate. The model equations used to describe how the compressor power consumption, heat exchange area and distilled water are related is based on a thermodynamic balance and heat transfer analysis, with correlations taken from the literature. Finally, the design calculations and the measurements of the installation are compared, showing accordance with the predictions in distillate production and power consumption, changing the temperature difference of the evaporator/condenser.Keywords: mechanical vapor compression, distillation, wastewater, design, construction, evaluation
Procedia PDF Downloads 1591434 Dynamic Environmental Impact Study during the Construction of the French Nuclear Power Plants
Authors: A. Er-Raki, D. Hartmann, J. P. Belaud, S. Negny
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This paper has a double purpose: firstly, a literature review of the life cycle analysis (LCA) and secondly a comparison between conventional (static) LCA and multi-level dynamic LCA on the following items: (i) inventories evolution with time (ii) temporal evolution of the databases. The first part of the paper summarizes the state of the art of the static LCA approach. The different static LCA limits have been identified and especially the non-consideration of the spatial and temporal evolution in the inventory, for the characterization factors (FCs) and into the databases. Then a description of the different levels of integration of the notion of temporality in life cycle analysis studies was made. In the second part, the dynamic inventory has been evaluated firstly for a single nuclear plant and secondly for the entire French nuclear power fleet by taking into account the construction durations of all the plants. In addition, the databases have been adapted by integrating the temporal variability of the French energy mix. Several iterations were used to converge towards the real environmental impact of the energy mix. Another adaptation of the databases to take into account the temporal evolution of the market data of the raw material was made. An identification of the energy mix of the time studied was based on an extrapolation of the production reference values of each means of production. An application to the construction of the French nuclear power plants from 1971 to 2000 has been performed, in which a dynamic inventory of raw material has been evaluated. Then the impacts were characterized by the ILCD 2011 characterization method. In order to compare with a purely static approach, a static impact assessment was made with the V 3.4 Ecoinvent data sheets without adaptation and a static inventory considering that all the power stations would have been built at the same time. Finally, a comparison between static and dynamic LCA approaches was set up to determine the gap between them for each of the two levels of integration. The results were analyzed to identify the contribution of the evolving nuclear power fleet construction to the total environmental impacts of the French energy mix during the same period. An equivalent strategy using a dynamic approach will further be applied to identify the environmental impacts that different scenarios of the energy transition could bring, allowing to choose the best energy mix from an environmental viewpoint.Keywords: LCA, static, dynamic, inventory, construction, nuclear energy, energy mix, energy transition
Procedia PDF Downloads 1051433 A Study of Anthropometric Correlation between Upper and Lower Limb Dimensions in Sudanese Population
Authors: Altayeb Abdalla Ahmed
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Skeletal phenotype is a product of a balanced interaction between genetics and environmental factors throughout different life stages. Therefore, interlimb proportions are variable between populations. Although interlimb proportion indices have been used in anthropology in assessing the influence of various environmental factors on limbs, an extensive literature review revealed that there is a paucity of published research assessing interlimb part correlations and possibility of reconstruction. Hence, this study aims to assess the relationships between upper and lower limb parts and develop regression formulae to reconstruct the parts from one another. The left upper arm length, ulnar length, wrist breadth, hand length, hand breadth, tibial length, bimalleolar breadth, foot length, and foot breadth of 376 right-handed subjects, comprising 187 males and 189 females (aged 25-35 years), were measured. Initially, the data were analyzed using basic univariate analysis and independent t-tests; then sex-specific simple and multiple linear regression models were used to estimate upper limb parts from lower limb parts and vice-versa. The results of this study indicated significant sexual dimorphism for all variables. The results indicated a significant correlation between the upper and lower limbs parts (p < 0.01). Linear and multiple (stepwise) regression equations were developed to reconstruct the limb parts in the presence of a single or multiple dimension(s) from the other limb. Multiple stepwise regression equations generated better reconstructions than simple equations. These results are significant in forensics as it can aid in identification of multiple isolated limb parts particularly during mass disasters and criminal dismemberment. Although a DNA analysis is the most reliable tool for identification, its usage has multiple limitations in undeveloped countries, e.g., cost, facility availability, and trained personnel. Furthermore, it has important implication in plastic and orthopedic reconstructive surgeries. This study is the only reported study assessing the correlation and prediction capabilities between many of the upper and lower dimensions. The present study demonstrates a significant correlation between the interlimb parts in both sexes, which indicates a possibility to reconstruction using regression equations.Keywords: anthropometry, correlation, limb, Sudanese
Procedia PDF Downloads 2951432 Physicochemical Investigation of Caffeic Acid and Caffeinates with Chosen Metals (Na, Mg, Al, Fe, Ru, Os)
Authors: Włodzimierz Lewandowski, Renata Świsłocka, Aleksandra Golonko, Grzegorz Świderski, Monika Kalinowska
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Caffeic acid (3,4-dihydroxycinnamic) is distributed in a free form or as ester conjugates in many fruits, vegetables and seasonings including plants used for medical purpose. Caffeic acid is present in propolis – a substance with exceptional healing properties used in natural medicine since ancient times. The antioxidant, antibacterial, antiinflammatory and anticarcinogenic properties of caffeic acid are widely described in the literature. The biological activity of chemical compounds can be modified by the synthesis of their derivatives or metal complexes. The structure of the compounds determines their biological properties. This work is a continuation of the broader topic concerning the investigation of the correlation between the electronic charge distribution and biological (anticancer and antioxidant) activity of the chosen phenolic acids and their metal complexes. In the framework of this study the synthesis of new metal complexes of sodium, magnesium, aluminium, iron (III) ruthenium (III) and osmium (III) with caffeic acid was performed. The spectroscopic properties of these compounds were studied by means of FT-IR, FT-Raman, UV-Vis, ¹H and ¹³C NMR. The quantum-chemical calculations (at B3LYP/LAN L2DZ level) of caffeic acid and selected complexes were done. Moreover the antioxidant properties of synthesized complexes were studied in relation to selected stable radicals (method of reduction of DPPH and method of reduction of ABTS). On the basis of the differences in the number, intensity and locations of the bands from the IR, Raman, UV/Vis and NMR spectra of caffeic acid and its metal complexes the effect of metal cations on the electronic system of ligand was discussed. The geometry, theoretical spectra and electronic charge distribution were calculated by the use of Gaussian 09 programme. The geometric aromaticity indices (Aj – normalized function of the variance in bond lengths; BAC - bond alternation coefficient; HOMA – harmonic oscillator model of aromaticity and I₆ – Bird’s index) were calculated and the changes in the aromaticity of caffeic acid and its complexes was discussed. This work was financially supported by National Science Centre, Poland, under the research project number 2014/13/B/NZ7/02-352.Keywords: antioxidant properties, caffeic acid, metal complexes, spectroscopic methods
Procedia PDF Downloads 2161431 The Role of Counselling Psychology on Expatriate Adjustment in East Asia: A Systematic Review
Authors: Panagiotis Platanitis
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Purpose: This research paper seeks to review the empirical studies in the field of expatriate adjustment in East Asia in order to produce a thematic understanding of the current adjustment challenges, thus enabling practitioners to enrich their knowledge. Background: Learning to live, work, and function in a country and culture vastly different from that of one’s upbringing can pose some unique challenges in terms of adaptation and adjustment. This has led to a growing body of research about the adjustment of expatriate workers. Adjustment itself has been posited as a three-dimensional construct; work adjustment, interaction adjustment and general or cultural adjustment. Methodology: This qualitative systematic review has been conducted on all identified peer-reviewed empirical studies related to expatriate adjustment in East Asia. Five electronic databases (PsychInfo, Emerald, Scopus, EBSCO and JSTOR) were searched to December 2015. Out of 625 identified records, thorough evaluation for eligibility resulted in 15 relevant studies being subjected to data analysis. The quality of the identified research was assessed according to the Standard Quality Assessment Criteria for Evaluating Primary Research Papers from a Variety of Fields. The data were analysed by means of thematic synthesis for systematic reviews of qualitative research. Findings: Data analysis revealed five key themes. The themes developed were: (1) personality traits (2) types of adjustment, (3) language, (4) culture and (5) coping strategies. Types of adjustment included subthemes such as: Interaction, general, work, psychological, sociocultural and cross-cultural adjustment. Conclusion: The present review supported previous literature on the different themes of adjustment and it takes the focus from work and general adjustment to the psychological challenges and it introduces the psychological adjustment. It also gives a different perspective about the use of cross-cultural training and the coping strategies expatriates use when they are abroad. This review helps counselling psychologists to understand the importance of a multicultural approach when working with expatriates and also to be aware of what expatriates might face when working and living in East Asia.Keywords: adjustment, counselling psychology, East Asia, expatriates
Procedia PDF Downloads 2661430 The Impacts of Foreign Culture on Yoruba Crime Films
Authors: Alonge Isaac Olusola
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This paper focuses on the evolution and development of Yoruba theatre during the pre-colonial, colonial and post-colonial years and how Yoruba crime films have been influenced by foreign culture. It emphasizes on the transition of theatre from the ground to the stage and from the stage to the screen with emphasis on the contribution of late Chief Hubert Ogunde who is regarded as the doyen of Yoruba and the entire Nigerian theatre. Using the Theory of Post-colonialism, two modern Yoruba crime films are carefully selected from the numerous available ones to highlight and explain the various aspects of Yoruba films that have been greatly influenced by the foreign cultural practices. The questions to be answered here include 'Which attitudes or cultural practices are widely believed to be that of Yoruba?', 'To what extent are they projected in the selected Yoruba crime films?', 'Which attitudes or cultural practices are widely believed to be foreign among the Yoruba people?', 'To what extent are they projected in the selected Yoruba crime films?'. Although, the British colonial masters granted political independence to Nigeria on October 1, 1960, but a seed of multi-culture and counterculture had been sown into the lives of the Yoruba people. Under the literature review, there is an intensive illumination on some scholars’ ideas and views on what constitutes Yoruba culture, the evolution and development of drama, theatre and films in the Yoruba society and the nature of criminals and criminalities in the Yoruba society and the western world in the pre-colonial and post-colonial times. Furthermore, the processes of interaction between man, his values and his thoughts are also highlighted – a situation that procreates criminal or benevolent acts. Consequently, the paper dwells on how colonialism, despite its so-called merits put the gradual process of urbanization and civilization among the originally rustic, cohesive and moralistic Yoruba society on a supersonic speed that culminated in acquisition of attitudes that are alien to the Yoruba culture. Since a drama is nothing but the theatrical replication of what occurs in the real life, the paper then focuses on the submission that Yoruba crime films have experienced a serious foreign influence in form and content as a result of this encounter. In conclusion, the findings of the impact of foreign cultural practices on Yoruba crime films are highlighted and expatiated with a view to recommending a few steps that could be taken to retain the projection of the original Yoruba cultural practices in Yoruba films, especially the ones that have crime as a theme.Keywords: culture, films, theatre, Yoruba
Procedia PDF Downloads 3031429 Computational Study on Traumatic Brain Injury Using Magnetic Resonance Imaging-Based 3D Viscoelastic Model
Authors: Tanu Khanuja, Harikrishnan N. Unni
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Head is the most vulnerable part of human body and may cause severe life threatening injuries. As the in vivo brain response cannot be recorded during injury, computational investigation of the head model could be really helpful to understand the injury mechanism. Majority of the physical damage to living tissues are caused by relative motion within the tissue due to tensile and shearing structural failures. The present Finite Element study focuses on investigating intracranial pressure and stress/strain distributions resulting from impact loads on various sites of human head. This is performed by the development of the 3D model of a human head with major segments like cerebrum, cerebellum, brain stem, CSF (cerebrospinal fluid), and skull from patient specific MRI (magnetic resonance imaging). The semi-automatic segmentation of head is performed using AMIRA software to extract finer grooves of the brain. To maintain the accuracy high number of mesh elements are required followed by high computational time. Therefore, the mesh optimization has also been performed using tetrahedral elements. In addition, model validation with experimental literature is performed as well. Hard tissues like skull is modeled as elastic whereas soft tissues like brain is modeled with viscoelastic prony series material model. This paper intends to obtain insights into the severity of brain injury by analyzing impacts on frontal, top, back, and temporal sites of the head. Yield stress (based on von Mises stress criterion for tissues) and intracranial pressure distribution due to impact on different sites (frontal, parietal, etc.) are compared and the extent of damage to cerebral tissues is discussed in detail. This paper finds that how the back impact is more injurious to overall head than the other. The present work would be helpful to understand the injury mechanism of traumatic brain injury more effectively.Keywords: dynamic impact analysis, finite element analysis, intracranial pressure, MRI, traumatic brain injury, von Misses stress
Procedia PDF Downloads 1621428 Reflecting on Deafblindness: Recommendations for Implementing Effective Strategies
Authors: V. Argyropoulos, M. Nikolaraizi, K. Tanou
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There is little available information concerning the cognitive and communicative abilities of the people who are deaf-blind. This mainly stems from the general inadequacy of existing assessment instruments employed with deafblind individuals. Although considerable variability exists with regard to cognitive capacities of the deaf-blind, careful examination of the literature reveals that the majority of these persons suffer from significant deficits in cognitive and adaptive functioning. The few reports available primarily are case studies, narrative program descriptions, or position papers by workers in the field. Without the objective verification afforded by controlled research, specialists in psychology, education, and other rehabilitation services must rely on personal speculations or biases to guide their decisions in the planning, implementation, and evaluation of services to deaf-blind children and adults. This paper highlights the framework and discusses the results of an action research network. The aim of this study was twofold: a) to describe and analyse the different ways in which a student with deafblindness approached a number of developmental issues such as novel tasks, exploration and manipulation of objects, reactions to social stimuli, motor coordination, and quality of play and b) to map the appropriate functional approach for the specific student that could be used to develop strategies for classroom participation and socialization. The persons involved in this collaborative action research scheme were general teachers, a school counsellor, academic staff and student teachers. Rating scales and checklists were used to gather information in natural activities and settings, and additional data were also obtained through interviews with the educators of the student. The findings of this case study indicated that there is a great need to focus on the development of effective intervention strategies. The results showed that the identification of positive reinforcers for this population might represent an important and challenging aspect of behaviour programmes. Finally, the findings suggest that additional empirical work is needed to increase attention to methodological and social validity issues.Keywords: action research, cognitive and communicative abilities, deafblindness, effective strategies
Procedia PDF Downloads 1851427 Sustainable Manufacturing of Concentrated Latex and Ribbed Smoked Sheets in Sri Lanka
Authors: Pasan Dunuwila, V. H. L. Rodrigo, Naohiro Goto
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Sri Lanka is one the largest natural rubber (NR) producers of the world, where the NR industry is a major foreign exchange earner. Among the locally manufactured NR products, concentrated latex (CL) and ribbed smoked sheets (RSS) hold a significant position. Furthermore, these products become the foundation for many products utilized by the people all over the world (e.g. gloves, condoms, tires, etc.). Processing of CL and RSS costs a significant amount of material, energy, and workforce. With this background, both manufacturing lines have immensely challenged by waste, low productivity, lack of cost efficiency, rising cost of production, and many environmental issues. To face the above challenges, the adaptation of sustainable manufacturing measures that use less energy, water, materials, and produce less waste is imperative. However, these sectors lack comprehensive studies that shed light on such measures and thoroughly discuss their improvement potentials from both environmental and economic points of view. Therefore, based on a study of three CL and three RSS mills in Sri Lanka, this study deploys sustainable manufacturing techniques and tools to uncover the underlying potentials to improve performances in CL and RSS processing sectors. This study is comprised of three steps: 1. quantification of average material waste, economic losses, and greenhouse gas (GHG) emissions via material flow analysis (MFA), material flow cost accounting (MFCA), and life cycle assessment (LCA) in each manufacturing process, 2. identification of improvement options with the help of Pareto and What-if analyses, field interviews, and the existing literature; and 3. validation of the identified improvement options via the re-execution of MFA, MFCA, and LCA. With the help of this methodology, the economic and environmental hotspots, and the degrees of improvement in both systems could be identified. Results highlighted that each process could be improved to have less waste, monetary losses, manufacturing costs, and GHG emissions. Conclusively, study`s methodology and findings are believed to be beneficial for assuring the sustainable growth not only in Sri Lankan NR processing sector itself but also in NR or any other industry rooted in other developing countries.Keywords: concentrated latex, natural rubber, ribbed smoked sheets, Sri Lanka
Procedia PDF Downloads 2611426 From Madrassah to Elite Schools; The Political Economy of Pluralistic Educational Systems in Pakistan
Authors: Ahmad Zia
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This study problematizes the notion that the pluralistic educational system in Pakistan fosters equality. Instead, it argues that this system not only reflects but also sustains existing class divisions, with implications for the future economic and social mobility of children. The primary goal of this study is to explore unequal access to educational opportunities in Pakistan. By examining the intersection between education and socioeconomic status, it attempts to explore the implications of key disparities in different tiers of education systems in Pakistan like between madrassahs, public schools and private schools, with an emphasis on how these institutions contribute to the maintenance of class hierarchies. This is a primary data based case study and the most recent data has been directly gathered Qualitative methods have been used to collect data from the units of data collection (UDCs). it have used Bourdieu’s theory as a leading framework. Its application in the context of country like Pakistan is very productive. it choose the thematic analysis method to analyse the data. This process helped me to identify relevant main themes and subthemes emerging from my data, which could comprise my analysis. Findings reveal that the educational landscape in Pakistan is deeply divided having far-reaching implications for social mobility and access to opportunities. This study found profound disparities among various educational institutions with respect to widening socioeconomic divides. Every kind of educational institution operates in a distinct socio-cultural and economic environment. Therefore, access to quality education is highly stratified and remains a privilege for only those who can afford it. This widens the socioeconomic gap that already exists. There has not been an extensive investigation of the relationship between pluralistic educations with class stratification in the literature so far. This study adds to a multifaceted understanding of educational disparities in Pakistan by analysing the intersections between socioeconomic divisions and educational access. It offers valuable theoretical and practical insights into the subject. This study provides theoretical concepts and empirical data to enhance scholars' understanding of socioeconomic inequality, specifically in relation to education systems.Keywords: social inequality, pluralism, class divide, capitalism, globalisation, elitism, education
Procedia PDF Downloads 101425 Signal Processing Techniques for Adaptive Beamforming with Robustness
Authors: Ju-Hong Lee, Ching-Wei Liao
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Adaptive beamforming using antenna array of sensors is useful in the process of adaptively detecting and preserving the presence of the desired signal while suppressing the interference and the background noise. For conventional adaptive array beamforming, we require a prior information of either the impinging direction or the waveform of the desired signal to adapt the weights. The adaptive weights of an antenna array beamformer under a steered-beam constraint are calculated by minimizing the output power of the beamformer subject to the constraint that forces the beamformer to make a constant response in the steering direction. Hence, the performance of the beamformer is very sensitive to the accuracy of the steering operation. In the literature, it is well known that the performance of an adaptive beamformer will be deteriorated by any steering angle error encountered in many practical applications, e.g., the wireless communication systems with massive antennas deployed at the base station and user equipment. Hence, developing effective signal processing techniques to deal with the problem due to steering angle error for array beamforming systems has become an important research work. In this paper, we present an effective signal processing technique for constructing an adaptive beamformer against the steering angle error. The proposed array beamformer adaptively estimates the actual direction of the desired signal by using the presumed steering vector and the received array data snapshots. Based on the presumed steering vector and a preset angle range for steering mismatch tolerance, we first create a matrix related to the direction vector of signal sources. Two projection matrices are generated from the matrix. The projection matrix associated with the desired signal information and the received array data are utilized to iteratively estimate the actual direction vector of the desired signal. The estimated direction vector of the desired signal is then used for appropriately finding the quiescent weight vector. The other projection matrix is set to be the signal blocking matrix required for performing adaptive beamforming. Accordingly, the proposed beamformer consists of adaptive quiescent weights and partially adaptive weights. Several computer simulation examples are provided for evaluating and comparing the proposed technique with the existing robust techniques.Keywords: adaptive beamforming, robustness, signal blocking, steering angle error
Procedia PDF Downloads 1241424 Classroom Curriculum That Includes Wisdom Skills
Authors: Brian Fleischli, Shani Robins
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In recent years, the implementation of wisdom skills, including emotional intelligence, mindfulness, empathy, compassion, gratitude, realism (Cognitive-Behavioral Therapy), and humility, within K-12 educational settings has demonstrated significant benefits in reducing stress, anxiety, anger, and conflict among students. This study summarizes the findings of research conducted over several years, showcasing the positive outcomes associated with teaching these skills to elementary and high school students. Additionally, this overview includes an updated synthesis of current literature concerning the application and effectiveness of training these skill sets in K-12 schools. The research outcomes highlight substantial improvements in student well-being and behavior. Demonstrated with treatment group students exhibiting notable reductions in anger, anxiety, depression, and disruptive behaviors compared to control groups. For instance, fourth-grade students showed enhanced empathy, responsibility, and attention, particularly benefiting those with lower initial scores on these measures. Specific interaction effects suggest that older students and males particularly benefit from these interventions, showcasing the nuanced impact of wisdom skill training across different demographics. Furthermore, this presentation emphasizes the critical role of Social and Emotional Learning (SEL) programs in addressing the multifaceted challenges faced by children and adolescents, including mental health issues, academic performance, and social behaviors. The integration of wisdom skills into school curricula not only fosters individual growth and emotional regulation but also enhances overall school climate and academic achievement. In conclusion, the findings contribute to the growing body of empirical evidence supporting the efficacy of teaching wisdom skills in educational settings. The success of these interventions underscores the potential for widespread implementation of evidence-based programs to promote emotional well-being and academic success among students nationwide.Keywords: wisdom skills, CBT, cognitive behavioral training, mindfulness, empathy, anxiety
Procedia PDF Downloads 451423 A Comparative Analysis of Lexical Bundles in Academic Writing: Insights from Persian and Native English Writers in Applied Linguistics
Authors: Elham Shahrjooi Haghighi
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This research explores how lexical bundles are utilized in writing in the field of linguistics by comparing professional Persian writers with native English writers using corpus-based studies and advanced computational techniques to examine the occurrence and characteristics of lexical bundles in academic writings. The review of literature emphasizes how important lexical bundles are, in organizing discussions and conveying opinions in both spoken and written language contexts across genres and proficiency levels in fields of study. Previous research has indicated that native English writers tend to employ an array and diversity of bundles than non-native writers do; these bundles are essential elements in academic writing. In this study’s methodology section, the research utilizes a corpus-based method to analyze a collection of writings such as research papers and advanced theses at the doctoral and masters’ levels. The examination uncovers variances in the utilization of groupings between writers who are native speakers of Persian and those who are native English speakers with the latter group displaying a greater occurrence and variety, in types of groupings. Furthermore, the research delves into how these groupings contribute to aspects classifying them into categories based on their relevance to research text structure and individuals as outlined in Hyland’s framework. The results show that Persian authors employ phrases and demonstrate distinct structural and functional tendencies in comparison to native English writers. This variation is linked to differing language skills, levels, disciplinary norms and cultural factors. The study also highlights the pedagogical implications of these findings, suggesting that targeted instruction on the use of lexical bundles could enhance the academic writing skills of non-native speakers. In conclusion, this research contributes to the understanding of lexical bundles in academic writing by providing a detailed comparative analysis of their use by Persian and native English writers. The insights from this study have important implications for language education and the development of effective writing strategies for non-native English speakers in academic contexts.Keywords: lexical bundles, academic writing, comparative analysis, computational techniques
Procedia PDF Downloads 211422 A Proposal for Professional Development of Mathematics Teachers in the Kingdom of Saudi Arabia According to the Orientation of Science, Technology, Engineering and Mathematics (STEM)
Authors: Ali Taher Othman Ali
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The aim of this research is to provide a draft proposal for the professional development of mathematics teachers in accordance with the orientation of science, technology, engineering and mathematics which is known by the abbreviation STEM, as a modern and contemporary orientation in the teaching and learning of mathematics and in order to achieve the objective of the research, the researcher used the theoretical descriptive method through the induction of the literature of education and the previous studies and experiments related to the topic. The researcher concluded by providing the proposal according to five basic axes, the first axe: professional development as a system, and its requirements include: development of educational systems, and allocate sufficient budgets to support the requirements of teaching STEM, identifying mechanisms for incentives and rewards for teachers attending professional development programs based on STEM; the second: development of in-depth knowledge content and its requirements include: basic sciences content development for STEM, linking the scientific understanding of teachers with real-world issues and problems, to provide the necessary resources to expand teachers' knowledge in this area; the third: the necessary pedagogical skills of teachers in the field of STEM, and its requirements include: identification of the required training and development needs and the mechanism of determining these needs, the types of professional development programs and the mechanism of designing it, the mechanisms and places of execution, evaluation and follow-up; the fourth: professional development strategies and mechanisms in the field of STEM, and its requirements include: using a variety of strategies to enable teachers to design and transfer effective educational experiences which reflect their scientific mastery in the fields of STEM, provide learning opportunities, and developing the skills of procedural research to generate new knowledge about the STEM; the fifth: to support professional development in the area of STEM, and its requirements include: support leadership within the school, provide a clear and appropriate opportunities for professional development for teachers within the school through professional learning communities, building partnerships between the Ministry of education and the local and international community institutions. The proposal includes other factors that should be considered when implementing professional development programs for mathematics teachers in the field of STEM.Keywords: professional development, mathematics teachers, the orientation of science, technology, engineering and mathematics (STEM)
Procedia PDF Downloads 4081421 Designing Nanowire Based Honeycomb Photonic Crystal Surface Emitting Lasers
Authors: Balthazar Temu, Zhao Yan, Bogdan-Petrin Ratiu, Sang Soon Oh, Qiang Li
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Photonic Crystal Surface Emitting Lasers (PCSELs) are structures which are made up of a periodically repeating patterns with a unit cell consisting of changes in refractive index. The variation in refractive index can be achieved by etching air holes in a semiconductor material to get hole based PCSELs or by growing nanowires to get nanowire based PCSELs. As opposed to hole based PCSELs, nanowire based PCSELs can be integrated on silicon platform without threading dislocations, thanks to the small area of the nanowire that is in contact with silicon substrate that relaxes the strain. Nanowire based PCSELs reported in the literature have been designed using a triangular, square or honeycomb patterns. The triangular and square pattern PCSELs have limited degrees of freedom in tuning the design parameters which hinders the ability to design high quality factor (Q-factor) and/or variable wavelength devices. Nanowire based PCSELs designed using triangular and square patterns have been reported with the lasing thresholds of 130 kW/〖cm〗^2 and 7 kW/〖cm〗^2 respectively. On the other hand the honeycomb pattern gives more degrees of freedom in tuning the design parameters, which can allow one to design high Q-factor devices. A deformed honeycomb pattern device was reported with lasing threshold of 6.25 W/〖cm〗^2 corresponding to a simulated Q-factor of 5.84X〖10〗^5.Despite this achievement, the design principles which can lead to realization of even higher Q-factor honeycomb pattern PCSELs have not yet been investigated. In this work we study how the resonance wavelength and the Q-factor of three different resonance modes of the device vary when their design parameters are tuned. Through this study we establish the design and simulation of devices operating in 970nm wavelength band, O band and in the C band with quality factors up to 7X〖10〗^7 . We also investigate the quality factors of undeformed device and establish that the band edge close to 970nm can attain high quality factor when the device is undeformed and the quality factor degrades as the device is deformed.Keywords: honeycomb PCSEL, nanowire laser, photonic crystal laser, simulation of photonic crystal surface emitting laser
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