Search results for: literature in foreign language studies

Authors: Paiboon Chuwatthanakij

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Each of the countries around the world has different ways of management and many of them depend on people to administrate their country. Thailand, for example, empowers the sovereignty of Thai people under constitution; however, our Thai voting system is not able to flow fast enough under the current Political management system. The sovereignty of Thai people is addressing this problem through representatives during current elections, in order to set a new policy for the countries ideology to change in the House and the Cabinet. This is particularly important in a democracy to be developed under our current political institution. The Organic Act on Political Parties 2007 is the establishment we have today that is causing confrontations within the establishment. There are many political parties that will soon be abolished. Many political parties have already been subsidized. This research study is to analyze the legal problems with the political party establishment under the Organic Act on Political Parties 2007. This will focus on the freedom of each political establishment compared to an effective political operation. Textbooks and academic papers will be referenced from studies home and abroad. The study revealed that Organic Act on Political Parties 2007 has strict provisions on the political structure over the number of members and the number of branches involved within political parties system. Such operations shall be completed within one year; but under the existing laws the small parties are not able to participate with the bigger parties. The cities are capable of fulfilling small political party requirements but fail to become coalesced because the current laws won't allow them to be united as one. It is important to allow all independent political parties to join our current political structure. Board members can’t help the smaller parties to become a large organization under the existing Thai laws. Creating a new establishment that functions efficiently throughout all branches would be one solution to these legal problems between all political parties. With this new operation, individual political parties can participate with the bigger parties during elections. Until current political institutions change their system to accommodate public opinion, these current Thai laws will continue to be a problem with all political parties in Thailand.

Keywords: coalesced, political party, sovereignty, elections

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Authors: Bolanle Deborah Motilewa, E. K. Rowland Worlu, Gbenga Mayowa Agboola, Ayodele Maxwell Olokundun

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Several studies have proposed a one-size fit all approach to Corporate Social Responsibility (CSR) practices, such that CSR as it applies to developed countries is adapted to developing countries, ignoring the differing institutional environments (such as the regulative, economic, social and political environments), which affects the profitability and practices of businesses operating in them. CSR as it applies to filling institutional gaps in developing countries, was categorized into four themes: environmental protection, product and service innovation, social innovation and local cluster development. Based on the four themes, the study employed a qualitative research approach through the use of interviews and review of available publications to study the influence of institutional environments on CSR practices engaged in by three renewable energy firms operating in Nigeria. Over the course of three 60-minutes sessions with the top management and selected workers of the firms, four propositions were made: regulatory environment influences environmental protection practice of Nigerian renewable firms, economic environment influences product and service innovation practice of Nigerian renewable energy firms, the social environment impacts on social innovation in Nigerian renewable energy firms, and political environment affects local cluster development practice of Nigerian renewable energy firms. It was also observed that beyond institutional environments, the international exposure of an organization’s managers reflected in their approach to CSR. This finding on the influence of international exposure on CSR practices creates an area for further study. Insights from this paper are set to help policy makers in developing countries, CSR managers, and future researchers.

Keywords: corporate social responsibility, renewable energy firms, institutional environment, social entrepreneurship

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Authors: Synthia A. Sari

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The transparent nomination and selection process is the first step to obtaining qualified members of board. It is believed as the representative (agent) of the owners, members of the board must consist of competent and professional people. However, the development of transparent and ideal nomination and selection process in Indonesian State-owned enterprises (SOEs) has been based on relatively little research. Considering the relative importance attached by boards to conduct their roles in their principal’s interest in a variety of governance tasks in state-owned enterprises, the primary aim of this paper is to shed light on the extent of nomination and selection process impact performance of the board in implementing good corporate governance in Indonesian SOEs. The exploratory nature of this study led to the adoption of a qualitative research methodology which uses semi-structured interviews and publically available documents to collect a range of data pertaining board nomination and selection and the work of boards. Interviews were conducted with four informants from three Indonesian SOEs and Ministry of SOEs. Findings in this study demonstrate unclear job description and expectations board members as a result of unclear functions of the board in Indonesian SOEs make transparent and accountable nomination and selection process hard to conduct. This situation is vulnerable to the influences from political interest and that even the process itself can degenerate into situations of political interference. In the end, it leads to choosing the wrong person for membership of the board. This study makes a significant contribution to several fields; the human resource management, corporate governance, and Southeast studies by addressing the basic research gaps of board selection process issues in Indonesian SOEs. The gap is addressed by providing a more coherent framework for effective nomination and selection system which reflects more clearly the real experiences of those actually involved at board level.

Keywords: board selection and nomination process, Indonesian stated-owned enterprises, good corporate governance, political influence

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Authors: Parinyaporn Thanaboonpuang, Siridej Sujiva, Shotiga Pasiphul

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The higher education reform that integration of nursing programmes into the higher education system. Learning outcomes represent one of the essential building blocks for transparency within higher education systems and qualifications. The purpose of this study is to develop a toolkit of undergraduate nursing student’desirable characteristics assessment on Thai Qualifications Framework for Higher education and to test psychometric property for this instrument. This toolkit seeks to improve on the Computer Multimedia test. There are three skills to be examined: Cognitive skill, Responsibility and Interpersonal Skill, and Information Technology Skill. The study was conduct in 4 phases. In Phase 1. Based on developed a measurement model and Computer Multimedia test. Phase 2 two round focus group were conducted, to determine the content validity of measurement model and the toolkit. In Phase 3, data were collected using a multistage random sampling of 1,156 senior undergraduate nursing student were recruited to test psychometric property. In Phase 4 data analysis was conducted by descriptive statistics, item analysis, inter-rater reliability, exploratory factor analysis and confirmatory factor analysis. The resulting TNDC consists of 74 items across the following four domains: Cognitive skill, Interpersonal Skill, Responsibility and Information Technology Skill. The value of Cronbach’ s alpha for the four domains were .781, 807, .831, and .865, respectively. The final model in confirmatory factor analysis fit quite well with empirical data. The TNDC was found to be appropriate, both theoretically and statistically. Due to these results, it is recommended that the toolkit could be used in future studies for Nursing Program in Thailand.

Keywords: toolkit, nursing student’ desirable characteristics, Thai qualifications framework

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Authors: Baha Eddine Aissou, Aichouche Belhadj Aissa

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Light detection and ranging (LiDAR) is an active remote sensing technology used for several applications. Airborne LiDAR is becoming an important technology for the acquisition of a highly accurate dense point cloud. A classification of airborne laser scanning (ALS) point cloud is a very important task that still remains a real challenge for many scientists. Support vector machine (SVM) is one of the most used statistical learning algorithms based on kernels. SVM is a non-parametric method, and it is recommended to be used in cases where the data distribution cannot be well modeled by a standard parametric probability density function. Using a kernel, it performs a robust non-linear classification of samples. Often, the data are rarely linearly separable. SVMs are able to map the data into a higher-dimensional space to become linearly separable, which allows performing all the computations in the original space. This is one of the main reasons that SVMs are well suited for high-dimensional classification problems. Only a few training samples, called support vectors, are required. SVM has also shown its potential to cope with uncertainty in data caused by noise and fluctuation, and it is computationally efficient as compared to several other methods. Such properties are particularly suited for remote sensing classification problems and explain their recent adoption. In this poster, the SVM classification of ALS LiDAR data is proposed. Firstly, connected component analysis is applied for clustering the point cloud. Secondly, the resulting clusters are incorporated in the SVM classifier. Radial basic function (RFB) kernel is used due to the few numbers of parameters (C and γ) that needs to be chosen, which decreases the computation time. In order to optimize the classification rates, the parameters selection is explored. It consists to find the parameters (C and γ) leading to the best overall accuracy using grid search and 5-fold cross-validation. The exploited LiDAR point cloud is provided by the German Society for Photogrammetry, Remote Sensing, and Geoinformation. The ALS data used is characterized by a low density (4-6 points/m²) and is covering an urban area located in residential parts of the city Vaihingen in southern Germany. The class ground and three other classes belonging to roof superstructures are considered, i.e., a total of 4 classes. The training and test sets are selected randomly several times. The obtained results demonstrated that a parameters selection can orient the selection in a restricted interval of (C and γ) that can be further explored but does not systematically lead to the optimal rates. The SVM classifier with hyper-parameters is compared with the most used classifiers in literature for LiDAR data, random forest, AdaBoost, and decision tree. The comparison showed the superiority of the SVM classifier using parameters selection for LiDAR data compared to other classifiers.

Keywords: classification, airborne LiDAR, parameters selection, support vector machine

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Authors: Tamaz Mdzinarashvili, Mariam Khvedelidze, Eka Shekiladze, Salome Chinchaladze, Mariam Mdzinarashvili

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The work is about the preparation of calcium-containing 1,2-Dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and 1,2-Dipalmitoyl-sn-glycero-3-phosphatidic acid (DPPA) and their calorimetric study. In order to prepare these complex liposomes, for the first stage it is necessary for ligands and lipids to directly interact, followed by the addition of pH-buffered water or solvent at temperatures slightly above the liposome phase transition temperature. The resulting mixture is briefly but vigorously shaken and then transformed into liposomes of the desired size using an extruder. Particle sizing and calorimetry were used to evaluate liposome formation. We determined the possible structure of calcium-containing liposomes made by our new technology and determined their thermostability. The paper provides calculations showing how many phospholipid molecules are required to make a 200 nm diameter liposome. Calculations showed that 33x10³ lipid molecules are needed to prepare one DPPA and DPPC liposome. Based on the calorimetric experiments, we determined that the structure of uncomplexed DPPA liposomes is unilaminar (one double layer), while DPPC liposome is a nanoparticle with a multilaminar (multilayer) structure. This was determined by the cooperativity of the heat absorption peak. Calorimetric studies of calcium liposomes made by our technology showed that calcium ions are placed in the multilaminar structure of the DPPC liposome. Calcium ions also formed a complex in the DPPA liposome structure, moreover, calcium made the DPPA liposome multilaminar, since the cooperative narrow heat absorption peak was transformed into a three-peak heat absorption peak. Since both types of liposomes in complex with calcium ions present a multilaminar structure, where the number of lipid heads in one particle is large, the number of calcium ions in one particle will also be increased. That makes it possible to use these nanoparticles as transporters of a large amount of calcium ions in a living organism.

Keywords: calcium, liposomes, thermodynamic parameters, calorimetry

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Authors: Jeff Chak-Fu Wong, Tony Chun Yin Yip

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The transition from secondary school to university seems exciting for many first-year students but can be more challenging than expected. Enabling instructors to know students’ learning habits and styles enhances their understanding of the students’ learning backgrounds, allows teachers to provide better support for their students, and has therefore high potential to improve teaching quality and learning, especially in any mathematics-related courses. The aim of this research is to collect students’ data using online surveys, to analyze students’ factors using learning analytics and educational data mining and to discover the characteristics of the students at risk of falling behind in their studies based on students’ previous academic backgrounds and collected data. In this paper, we use correlation-based distance methods and mutual information for measuring student factor relationships. We then develop a factor network using the Minimum Spanning Tree method and consider further study for analyzing the topological properties of these networks using social network analysis tools. Under the framework of mutual information, two graph-based feature filtering methods, i.e., unsupervised and supervised infinite feature selection algorithms, are used to analyze the results for students’ data to rank and select the appropriate subsets of features and yield effective results in identifying the factors affecting students at risk of failing. This discovered knowledge may help students as well as instructors enhance educational quality by finding out possible under-performers at the beginning of the first semester and applying more special attention to them in order to help in their learning process and improve their learning outcomes.

Keywords: students' academic performance, correlation-based distance method, social network analysis, feature selection, graph-based feature filtering method

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Authors: Tahani Amutairi, Paul May, Neil Allan

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Many properties of semiconductor materials (mechanical, electronic, magnetic, and optical) can be significantly modified by introducing a point defect. Diamond offers extraordinary properties as a semiconductor, and doping seems to be a viable method of solving the problem associated with the fabrication of diamond-based electronic devices in order to exploit those properties. The dopants are believed to play a significant role in reducing the energy barrier to conduction and controlling the mobility of the carriers and the resistivity of the film. Although it has been proven that the n-type diamond semiconductor can be obtained with phosphorus doping, the resulting ionisation energy and mobility are still inadequate for practical application. Theoretical studies have revealed that this is partly because the effects of the many phosphorus atoms incorporated in the diamond lattice are compensated by acceptor states. Using spin-polarised hybrid density functional theory and a supercell approach, we explored the effects of bonding one N atom to a P in adjacent substitutional sites in diamond. A range of hybrid functional, including HSE06, B3LYP, PBE0, PBEsol0, and PBE0-13, were used to calculate the formation, binding, and ionisation energies, in order to explore the solubility and stability of the point defect. The equilibrium geometry and the magnetic and electronic structures were analysed and presented in detail. The defect introduces a unique reconstruction in a diamond where one of the C atoms coordinated with the N atom involved in the elongated C-N bond and creates a new bond with the P atom. The simulated infrared spectra of phosphorus-nitrogen defects were investigated with different supercell sizes and found to contain two sharp peaks at the edges of the spectrum, one at a high frequency 1,379 cm⁻¹ and the second appearing at the end range, 234 cm⁻¹, as obtained with the largest supercell (216).

Keywords: DFT, HSE06, B3LYP, PBE0, PBEsol0, PBE0-13

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Authors: Atinder Pal Kaur

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A central characteristic of people is their apparent movement from one station to other for their sustenance. Human migration has become one of the most challenging issues faced by the world today. Migration represents an important dimension in world-wide setting; and remittances received by families constitute a major agent in integrating societies in the all over the world, both economically and socially. This paper is an attempt to explore the impact of male migration and remittances upon the family system. This paper brings out how the women play the role of head of the household and take all the economic decisions, but still faces discrimination in the family, that bring loneliness and emotional breakdown on their personal front. For the purpose of this study, data was collected using 30 interviews and 10 case studies in the Doaba region of Punjab. The respondents were classified into two age groups 20-35 years and above 40 years aged women whose husbands migrated abroad. The findings of this study revealed that even though the women were taking some of the economic decisions, but in majority of the cases the patriarchal structure still existed and power remained in the hands of their husbands or in-laws. It was found that women of different age groups reported differently in terms of authority that they have regarding remittances and its consequences in their emotional well-being. The distinction related to their participation in public and private spheres still exists and public spheres are mostly dominated by male members of the family. It can be concluded that freedom of women to take decision on their own is still restricted and they are subjugated to follow their husband or in-law’s opinion in matters related to both public and private spheres. However, old age group women enjoyed more independence and freedom to take decision in comparison to young age women. Loneliness and depression were more common in the young age respondent’s group than in old age women.

Keywords: gender discrimination, migration, patriarchal structure, remittances

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Authors: Alexander Kospach, Fabian Benezeder, Jürgen Abraham

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E-mobility poses new challenges for inverters (e.g., higher switching frequencies) in terms of thermal behavior and thermal management. Due to even higher switching frequencies, thermal losses become greater, and the cooling of critical components (like insulated gate bipolar transistor and diodes) comes into focus. New manufacturing methods, such as 3D printing, enable completely new pin-fin structures that can handle higher waste heat to meet the new thermal requirements. Based on the geometrical specifications of the industrial partner regarding the manufacturing possibilities for 3D printing, different and completely new pin-fin structures were numerically investigated for their hydraulic and thermal behavior in fundamental studies assuming an indirect liquid cooling. For the 3D computational fluid dynamics (CFD) thermal simulations OpenFOAM was used, which has as numerical method the finite volume method for solving the conjugate heat transfer problem. A steady-state solver for turbulent fluid flow and solid heat conduction with conjugate heat transfer between solid and fluid regions was used for the simulations. In total, up to fifty pinfin structures and arrangements, some of them completely new, were numerically investigated. On the basis of the results of the principal investigations, the best two pin-fin structures and arrangements for the complete module cooling of an automotive inverter were numerically investigated and compared. There are clear differences in the maximum temperatures for the critical components, such as IGTBs and diodes. In summary, it was shown that 3D pin fin structures can significantly contribute to the improvement of heat transfer and cooling of an automotive inverter. This enables in the future smaller cooling designs and a better lifetime of automotive inverter modules. The new pin fin structures and arrangements can also be applied to other cooling applications where 3D printing can be used.

Keywords: pin fin heat sink optimization, 3D printed pin fins, CFD simulation, power electronic cooling, thermal management

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Authors: Alina Smalinskiene Janina Petkeviciene, Jurate Klumbiene, Vilma Kriaucioniene, Vaiva Lesauskaite

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The worldwide prevalence of obesity has been increasing dramatically in the last few decades, and Lithuania is no exception. In 2012, every fifth adult (19% of men and 20.5 % of women) was obese and every third was overweight Association studies have highlighted the influence of SNPs in obesity, with particular focus on FTO rs9939609. Thus far, no data on the possible association of this SNP to obesity in the adult Lithuanian population has been reported. Here, for the first time, we demonstrate an association between the FTO rs9939609 homozygous AA genotype and increased BMI when compared to homozygous TT. Furthermore, a positive association was determined between the FTO rs9939609 variant and risk of metabolic syndrome. Background: This study aimed to examine the associations between the fat mass and obesity associated (FTO) gene rs9939609 variant with obesity and metabolic syndrome in Lithuanian adult population. Materials and Methods: A cross-sectional health survey was carried out in randomly selected municipalities of Lithuania. The random sample was obtained from lists of 25–64 year-old inhabitants. The data from 1020 subjects were analysed. The rs9939609 SNP of the FTO gene was assessed using TaqMan assays (Applied Biosystems, Foster City, CA, USA). The Applied Biosystems 7900HT Real-Time Polymerase Chain Reaction System was used for detecting the SNPs. Results: The carriers of the AA genotype had the highest mean values of BMI and waist circumference (WC) and the highest risk of obesity. Interactions ‘genotype x age’ and ‘genotype x physical activity’ in determining BMI and WC were shown. Neither lipid and glucose levels, nor blood pressure were associated with the rs9939609 independently of BMI. In the age group of 25-44 years, association between the FTO genotypes and metabolic syndrome was found. Conclusion: The FTO rs9939609 variant was significantly associated with BMI and WC, and with the risk of obesity in Lithuanian population. The FTO polymorphism might have a greater influence on weight status in younger individuals and in subjects with a low level of physical activity.

Keywords: obesity metabolic syndrome, FTO gene, polymorphism, Lithuania

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Authors: María González Alriols, Itziar Egües, María A. Andrés, Mirari Antxustegi

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Several collaborative learning proposals were prepared to be applied in the laboratory sessions of chemistry in the first course of engineering studies. The aim was to engage the students from the beginning and to avoid absenteeism as well as to reach a more homogeneous level in the class. The students, divided into small groups of four or five mates, were asked to do an exercise before having the practical session in the lab. Precisely, each one of the groups was asked to study the theoretical fundamentals and the practical aspects of one lab session and to prepare a didactical video with this content, including the materials, equipment and reactants required, and the detailed experimental procedure. Furthermore, they should include the performance of the experiment step by step, indicating the faced difficulties and the obtained results and conclusions. After watching the video of this precise activity, the other groups of students would go to the lab to put into practice the session following the commands explained in the video. The evaluation of the video activity that is worth the 50% of the total mark of the laboratory sessions, is done depending on the success that the other groups of students had while doing the practical session that was explained in the video. This means that the successful transmission of knowledge to the rest of the mates in the class through the video was compulsory to pass the practical sessions and the subject. The other 50% of the mark depended on the understanding of the other students’ explanations and the success in the corresponding practical sessions. The experience was found to be very positive, as the engagement level was considerably higher, the absenteeism lower and the attitude in the laboratory much more responsible. The materials, reactants and equipment were used carefully, and no incidents were registered. Furthermore, the fact of having peer experts was useful to encourage critical thinking in a more relaxed way, with the teacher figure in a secondary position. Finally, the academic achievements were satisfactory as well, with a high percentage of students over the level required for passing the subject.

Keywords: collaborative learning, engineering instruction, chemistry, laboratory sessions

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Authors: Sima Parvizi Omran, Rezvan Tavakoli, Mahnaz Safari, Mohammadreza Aghasadeghi, Abolfazl Fateh, Pooneh Rahimi

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Background: SARS-CoV-2, a single-stranded RNA betacoronavirus causes the global outbreak of coronavirus disease 2019 (COVID-19). Several clinical and scientific concerns are raised by this pandemic. Genetic factors can contribute to pathogenesis and disease susceptibility. There are single nucleotide polymorphisms (SNPs) in many of the genes in the immune system that affect the expression of specific genes or functions of some proteins related to immune responses against viral infections. In this study, we analyzed the impact of polymorphism in the interferon alpha and beta receptor subunit 2 (IFNAR2) and dipeptidyl peptidase 9 (Dpp9) genes and clinical parameters on the susceptibility and resistance to Coronavirus disease (COVID-19). Methods: A total of 330- SARS-CoV-2 positive patients (188 survivors and 142 nonsurvivors) were included in this study. All single-nucleotide polymorphisms (SNPs) on IFNAR2 (rs2236757) and Dpp9 (rs2109069) were genotyped by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Results: In survivor patients, the frequency of the favourable genotypes of IFNAR2 SNP (rs2236757 GC) was significantly higher than in nonsurvivor patients, and also Dpp9 (rs2109069 AT) genotypes were associated with the severity of COVID-19 infection. Conclusions: This study demonstrated that the severity of COVID- 19 patients was strongly associated with clinical parameters and unfavourable IFNAR2, Dpp9 SNP genotypes. In order to establish the relationship between host genetic factors and the severity of COVID-19 infection, further studies are needed in multiple parts of the world.

Keywords: SARS-CoV-2, COVID-19, interferon alpha and beta receptor subunit 2, dipeptidyl peptidase 9, single-nucleotide polymorphisms

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Authors: Ahmad Ammar, Umar Khan Khattak, Muhammad Majid

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Empirically based lumped hydrologic models have an extensive track record of use for various watershed managements and flood related studies. This study focuses on the impacts of LULC change for 10 year period on the discharge in watershed using lumped model HEC-HMS. The Indus above Tarbela region acts as a source of the main flood events in the middle and lower portions of Indus because of the amount of rainfall and topographic setting of the region. The discharge pattern of the region is influenced by the LULC associated with it. In this study the Landsat TM images were used to do LULC analysis of the watershed. Satellite daily precipitation TRMM data was used as input rainfall. The input variables for model building in HEC-HMS were then calculated based on the GIS data collected and pre-processed in HEC-GeoHMS. SCS-CN was used as transform model, SCS unit hydrograph method was used as loss model and Muskingum was used as routing model. For discharge simulation years 2000 and 2010 were taken. HEC-HMS was calibrated for the year 2000 and then validated for 2010.The performance of the model was assessed through calibration and validation process and resulted R2=0.92 during calibration and validation. Relative Bias for the years 2000 was -9% and for2010 was -14%. The result shows that in 10 years the impact of LULC change on discharge has been negligible in the study area overall. One reason is that, the proportion of built-up area in the watershed, which is the main causative factor of change in discharge, is less than 1% of the total area. However, locally, the impact of development was found significant in built up area of Mansehra city. The analysis was done on Mansehra city sub-watershed with an area of about 16 km2 and has more than 13% built up area in 2010. The results showed that with an increase of 40% built-up area in the city from 2000 to 2010 the discharge values increased about 33 percent, indicating the impact of LULC change on discharge value.

Keywords: LULC change, HEC-HMS, Indus Above Tarbela, SCS-CN

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Authors: Inga Badasyan

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Every year we do monitoring of water pollution of catchment basin of Debed River. Next, the Ministry of Nature Protection does modeling programme. Finely, we are managing the impact of water pollution in Debed river. Ecosystem technologies efficiency performance were estimated based on the physical, chemical, and macrobiological analyses of water on regular base between 2012 to 2015. Algae community composition was determined to assess the ecological status of Debed river, while vegetation was determined to assess biodiversity. Last time, experts werespeaking about global warming, which is having bad impact on the surface water, freshwater, etc. As, we know that global warming is caused by the current high levels of carbon dioxide in the water. Geochemical modelling is increasingly playing an important role in various areas of hydro sciences and earth sciences. Geochemical modelling of highly concentrated aqueous solutions represents an important topic in the study of many environments such as evaporation ponds, groundwater and soils in arid and semi-arid zones, costal aquifers, etc. The sampling time is important for benthic macroinvertebrates, for that reason we have chosen in the spring (abundant flow of the river, the beginning of the vegetation season) and autumn (the flow of river is scarce). The macroinvertebrates are good indicator for a chromic pollution and aquatic ecosystems. Results of our earlier investigations in the Debed river reservoirs clearly show that management problem of ecosystem reservoirs is topical. Research results can be applied to studies of monitoring water quality in the rivers and allow for rate changes and to predict possible future changes in the nature of the lake.

Keywords: ecohydrological monitoring, flood risk management, global warming, aquatic macroinvertebrates

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Authors: Riaz A. Agha, Ishani Barai, Shivanchan Rajmohan, Seon Lee, Mohammed O. Anwar, Alex J. Fowler, Dennis P. Orgill, Douglas G. Altman

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Introduction: Medical knowledge is growing fast. Evidence-based medicine works best if the evidence is reported well. Past studies have shown reporting quality to be lacking in the field of surgery. Reporting guidelines are an important tool for authors to optimize the reporting of their research. The objective of this study was to analyse the frequency and strength of recommendation for such reporting guidelines within surgical journals. Methods: A systematic review of the 198 journals within the Journal Citation Report 2014 (surgery category) published by Thomson Reuters was undertaken. The online guide for authors for each journal was screened by two independent groups and results were compared. Data regarding the presence and strength of recommendation to use reporting guidelines was extracted. Results: 193 journals were included (as five appeared twice having changed their name). These had a median impact factor of 1.526 (range 0.047 to 8.327), with a median of 145 articles published per journal (range 29-659), with 34,036 articles published in total over the two-year window 2012-2013. The majority (62%) of surgical journals made no mention of reporting guidelines within their guidelines for authors. Of the journals (38%) that did mention them, only 14% (10/73) required the use of all relevant reporting guidelines. The most frequently mentioned reporting guideline was CONSORT (46 journals). Conclusion: The mention of reporting guidelines within the guide for authors of surgical journals needs improvement. Authors, reviewers and editors should work to ensure that research is reported in line with the relevant reporting guidelines. Journals should consider hard-wiring adherence to them. This will allow peer-reviewers to focus on what is present, not what is missing, raising the level of scholarly discourse between authors and the scientific community and reducing frustration amongst readers.

Keywords: CONSORT, guide for authors, PRISMA, reporting guidelines, journal impact factor, citation analysis

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Authors: Michele Gattullo, Vito M. Manghisi, Alessandro Evangelista, Enricoandrea Laviola

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In this work, we explored the use of Augmented Reality (AR) to support students in laboratory lectures in Distance Learning (DL), designing an application that proved to be ready for use next semester. AR could help students in the understanding of complex concepts as well as increase their motivation in the learning process. However, despite many prototypes in the literature, it is still less used in schools and universities. This is mainly due to the perceived limited advantages to the investment costs, especially regarding changes needed in the teaching modalities. However, with the spread of epidemiological emergency due to SARS-CoV-2, schools and universities were forced to a very rapid redefinition of consolidated processes towards forms of Distance Learning. Despite its many advantages, it suffers from the impossibility to carry out practical activities that are of crucial importance in STEM ("Science, Technology, Engineering e Math") didactics. In this context, AR perceived advantages increased a lot since teachers are more prepared for new teaching modalities, exploiting AR that allows students to carry on practical activities on their own instead of being physically present in laboratories. In this work, we designed an AR application for the support of engineering students in the understanding of assembly drawings of complex machines. Traditionally, this skill is acquired in the first years of the bachelor's degree in industrial engineering, through laboratory activities where the teacher shows the corresponding components (e.g., bearings, screws, shafts) in a real machine and their representation in the assembly drawing. This research aims to explore the effectiveness of AR to allow students to acquire this skill on their own without physically being in the laboratory. In a preliminary phase, we interviewed students to understand the main issues in the learning of this subject. This survey revealed that students had difficulty identifying machine components in an assembly drawing, matching between the 2D representation of a component and its real shape, and understanding the functionality of a component within the machine. We developed a mobile application using Unity3D, aiming to solve the mentioned issues. We designed the application in collaboration with the course professors. Natural feature tracking was used to associate the 2D printed assembly drawing with the corresponding 3D virtual model. The application can be displayed on students’ tablets or smartphones. Users could interact with selecting a component from a part list on the device. Then, 3D representations of components appear on the printed drawing, coupled with 3D virtual labels for their location and identification. Users could also interact with watching a 3D animation to learn how components are assembled. Students evaluated the application through a questionnaire based on the System Usability Scale (SUS). The survey was provided to 15 students selected among those we participated in the preliminary interview. The mean SUS score was 83 (SD 12.9) over a maximum of 100, allowing teachers to use the AR application in their courses. Another important finding is that almost all the students revealed that this application would provide significant power for comprehension on their own.

Keywords: augmented reality, distance learning, STEM didactics, technology in education

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Authors: Yongquan Zhao, Bo Huang

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Spatial, Temporal, and Spectral Resolution (STSR) are three key characteristics of Earth observation satellite sensors; however, any single satellite sensor cannot provide Earth observations with high STSR simultaneously because of the hardware technology limitations of satellite sensors. On the other hand, a conflicting circumstance is that the demand for high STSR has been growing with the remote sensing application development. Although image fusion technology provides a feasible means to overcome the limitations of the current Earth observation data, the current fusion technologies cannot enhance all STSR simultaneously and provide high enough resolution improvement level. This study proposes a Hybrid Spatial-Temporal-Spectral image Fusion Model (HSTSFM) to generate synthetic satellite data with high STSR simultaneously, which blends the high spatial resolution from the panchromatic image of Landsat-8 Operational Land Imager (OLI), the high temporal resolution from the multi-spectral image of Moderate Resolution Imaging Spectroradiometer (MODIS), and the high spectral resolution from the hyper-spectral image of Hyperion to produce high STSR images. The proposed HSTSFM contains three fusion modules: (1) spatial-spectral image fusion; (2) spatial-temporal image fusion; (3) temporal-spectral image fusion. A set of test data with both phenological and land cover type changes in Beijing suburb area, China is adopted to demonstrate the performance of the proposed method. The experimental results indicate that HSTSFM can produce fused image that has good spatial and spectral fidelity to the reference image, which means it has the potential to generate synthetic data to support the studies that require high STSR satellite imagery.

Keywords: hybrid spatial-temporal-spectral fusion, high resolution synthetic imagery, least square regression, sparse representation, spectral transformation

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Authors: Chung Gun Lee

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Objectives: Certain life change events were shown to have strong effects on physical activity-related behavior, but more research is needed to investigate the longer-term effects of different life change events on physical activity-related behaviors. The purpose of this study is to examine the effect of experiencing physically or non-physically forced sexual activity on sports participation from adolescence to young adulthood. Methods: This study used the National Longitudinal Study of Adolescent Health (Add Health) data. Group-based trajectory modeling was utilized to examine the effect of experiencing sexual assault on trajectories of sports participation from adolescence to young adulthood. Results: Male participants were divided into three trajectory groups (i.e., Low-stable, High-decreasing, and High-stable) and female participants were divided into two trajectory groups (i.e., Low-stable and High-decreasing). The main finding of this study is that women who experienced non-physically forced sexual activity significantly decreases sports participation throughout the trajectory in ‘High-decreasing group.’ The effect of non-physically forced sexual activity on women’s sports participation was considerably weakened and became insignificant after including psychological depression in the model as a potential mediator. Discussion: Special attention should be paid to sport participation among women victims of non-physically forced sexual activity. Further studies are needed to examine other potential mediators in addition to psychological depression when examining the effect of non-physically forced sexual activity on sport participation in women.

Keywords: adolescent, group-based trajectory modeling, sexual assault, young adult

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Authors: Ibrahim M. Labouta, Gina N. Tageldin, Salwa M. Fahmy, Hayam M. Ashour, Mounir A. Khalil, Tamer M. Ibrahim, Nefertiti A. El-Nikhely

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Bruton’s tyrosine kinase (BTK) is a critical effector molecule in B cell antigen receptor (BCR) signaling transduction. It regulates B cell proliferation, development and survival. Since BTK is widely expressed in many B cell leukaemias and lymphomas, targeting BTK by small molecules inhibitors became an attractive idea as new treatment modalities for B cell mediated hematologic malignancies. Ibrutinib is the 1st generation BTK inhibitor, approved by FDA for treatment of relapsed mantle cell lymphoma (MCL) and chronic lymphocytic leukemia (CLL). It binds irreversibly to the unique cysteine (Cys481) within the ATP-binding pocket of BTK. Besides ibrutinib, many irreversible covalent BTK inhibitors comprising pyrimidine nucleus such as spebrutinib (phase IIb) showed high selectivity and potency when compared to it. In this study, the designed compounds were based on 5-cyano-2-methylsulfanyl pyrimidine core and decorated with electrophilic warheads which are essential for the optimal activity for targeted covalent inhibition (TCI). However, modifications at pyrimidine C4 or C6 were made by introduction of substituted amines which are provided to behave differently. The synthesized derivatives were evaluated for their anticancer activity in leukemia cell lines (e.g. THP-1). Results showed that, some derivatives exhibited antiproliferative activity with IC50 ranged from 5-50 μM, The in vitro enzymatic inhibitory assay for these compounds against BTK is still under investigation. Nevertheless, we could conclude from the initial biological screening that, the synthesized 4 or 6-subsitituted aminopyrimidines represent promising and novel antileukemic agents. Meanwhile, further studies are still needed to attribute this activity through targeting BTK enzyme and inhibition of BCR signaling pathway.

Keywords: BTK inhibitors, hematologic malignancies, structure based drug design (SBDD), targeted covalent inhibitors (TCI)

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Authors: Hamida Memon, Muhammad Sanan

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A 34-year-old male with no prior health issues presented with a wound in his left leg exhibiting active pus discharge, intense inflammation, pain radiating from the buttocks to the knee, foot drop, and skin darkening. Four years prior, he sustained an untreated dislocation of the hip joint and acetabulum from a road traffic accident. Initial nerve conduction studies (NCS) and electromyography (EMG) revealed severe axonotomesis of the left sciatic nerve and reduced compound muscle action potential in the left common peroneal nerve. Despite normal venous flow, edema and cellulitis were noted. Follow-up NCS/EMG in 2022 showed improvement, but in 2023, the patient experienced recurrent infection and underwent surgical intervention with tissue culture. Postoperative care included antibiotics and pain management. NCS/EMG in 2024 indicated decreased nerve amplitudes and conduction velocities, consistent with moderate axonotmesis and ongoing recovery, alongside incidental right S1 radiculopathy. General lab tests and abdominal imaging were normal. The patient was treated with Pregabalin and Neurobion for neuropathic pain and nerve support and is currently under observation by a tertiary sector hospital for treatment. This case underscores the critical importance of prompt treatment for hip dislocations to prevent long-term complications such as neuropathy and avascular necrosis. Delays in treatment significantly increase the risk of severe outcomes, highlighting the need for timely intervention. Overall, the case illustrates the challenges of managing complex nerve injuries and the importance of comprehensive care for optimal recovery.

Keywords: sciatic nerve neuropathy, hip dislocation, acetabular fracture, radiculopathy

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Authors: Kalsoom Rani

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Tobacco contains nicotine, which causes addiction to many toxic chemicals. In the world, people consume it in the form of smoke, chew, and sniffing, smoke of it is composed of almost 7000 active chemicals, which are very harmful to human health as well as for eye health, inhalation of tobacco smoke and fumes can accelerate and cause many blinding eye diseases. Dry eye and smoking have not been covered extensively in researches; more studies are required to unveil the relationship between smoking and dry eye. This study was conducted to determine the quantity and quality of tears in smokers. 60 subjects participated in the study, which was divided into two groups on the basis of consumption of cigarettes per day with age matched non smokers of 15-50 years. All participants have gone through a study based questioner, eye examination, and diagnostic 'Dry Eye Tests' for evaporative tears evaluation and measurement of basal tear secretion. Subjects were included in the criteria of 10 cigarettes per day with a minimum duration of 1 year; passive smokers for control groups were excluded. The study was carried out in a Medina Teaching Hospital, Faisalabad, Pakistan, ophthalmology department for the duration of 8 months. Mean values for tear break up time (TBUT), was reported 10sec with SD of +3.74 in controlled group, 5sec with SD + 2.32 in smokers and 4sec SD +3.77 heavy smokers in right eye (RE) and left eye (LE) 10.35sec with SD of +3.88 in controlled 5sec with SD + 2.3 in smokers and much reduced TBUT in heavy smokers was 3.85sec SD+2.20. Smoking has a very strong association with TRUT with a significance of P=.00 both eyes. Mean Schirmer-I value of the subjects was reported 12.6mm with SD + 8.37 in RE and 12.59mm with SD + 8.96 LE. The mean Schirmer-II test value was reported in the right, and left eye with a mean value for control was 20.23mm with SD + 8.93, 20.75mm with SD + 8.84 respectively, and in Smokers 9.90mm with SD + 5.74, and 10.07mm with SD + 6.98, and in heavy smokers 7.7mm, SD + 3.22 and 6.9, SD + 3.50 mm, association with smoking showed p=.001 in RE and .003 in LE. Smoking has deteriorated effect on both evaporative tear and aqueous tear secretion and causing symptoms of dry eye burning, itching, redness, and watering with epithelial cell damage.

Keywords: tear break-up time, basal tear secretion, smokers, dry eye

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Authors: Stehr Melanie

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The availability of apposite information is essential for the decision-making process of organizational buyers. Due to the constraints of the Covid-19 crisis, information channels that emphasize face-to-face contact (e.g. sales visits, trade shows) have been unavailable, and usage of digitally-driven information channels (e.g. videoconferencing, platforms) has skyrocketed. This paper explores the question in which areas the pandemic induced shift in the use of information channels could be sustainable and in which areas it is a temporary phenomenon. While information and buying behavior in B2C purchases has been regularly studied in the last decade, the last fundamental model of organizational buying behavior in B2B was introduced by Johnston and Lewin (1996) in times before the advent of the internet. Subsequently, research efforts in B2B marketing shifted from organizational buyers and their decision and information behavior to the business relationships between sellers and buyers. This study builds on the extensive literature on situational factors influencing organizational buying and information behavior and uses the economics of information theory as a theoretical framework. The research focuses on the German woodworking industry, which before the Covid-19 crisis was characterized by a rather low level of digitization of information channels. By focusing on an industry with traditional communication structures, a shift in information behavior induced by an exogenous shock is considered a ripe research setting. The study is exploratory in nature. The primary data source is 40 in-depth interviews based on the repertory-grid method. Thus, 120 typical buying situations in the woodworking industry and the information and channels relevant to them are identified. The results are combined into clusters, each of which shows similar information behavior in the procurement process. In the next step, the clusters are analyzed in terms of the post and pre-Covid-19 crisis’ behavior identifying stable and dynamic information behavior aspects. Initial results show that, for example, clusters representing search goods with low risk and complexity suggest a sustainable rise in the use of digitally-driven information channels. However, in clusters containing trust goods with high significance and novelty, an increased return to face-to-face information channels can be expected after the Covid-19 crisis. The results are interesting from both a scientific and a practical point of view. This study is one of the first to apply the economics of information theory to organizational buyers and their decision and information behavior in the digital information age. Especially the focus on the dynamic aspects of information behavior after an exogenous shock might contribute new impulses to theoretical debates related to the economics of information theory. For practitioners - especially suppliers’ marketing managers and intermediaries such as publishers or trade show organizers from the woodworking industry - the study shows wide-ranging starting points for a future-oriented segmentation of their marketing program by highlighting the dynamic and stable preferences of elaborated clusters in the choice of their information channels.

Keywords: B2B buying process, crisis, economics of information theory, information channel

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Authors: Ming-Chan Chung, Wen-Ming Huang, Yi-Chu Liu, Li-Hui Yang, Ming-Jyh Chen

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introduction: Hospital buildings require considerable energy, including air conditioning, lighting, elevators, heating, and medical equipment. Energy consumption in hospitals is expected to increase significantly due to innovative equipment and continuous development plans. Consequently, the environment and climate will be adversely affected. Hospitals should therefore consider transforming from their traditional role of saving lives to being at the forefront of global efforts to reduce carbon dioxide emissions. As healthcare providers, it is our responsibility to provide a high-quality environment while using as little energy as possible. Purpose / Methods: Compare the energy-saving benefits of solar photovoltaic systems and solar hot water systems. The proportion of electricity consumption effectively reduced after the installation of solar photovoltaic systems. To comprehensively assess the potential benefits of utilizing solar energy for both photovoltaic (PV) and solar thermal applications in hospitals, a solar PV system was installed covering a total area of 28.95 square meters in 2021. Approval was obtained from the Taiwan Power Company to integrate the system into the hospital's electrical infrastructure for self-use. To measure the performance of the system, a dedicated meter was installed to track monthly power generation, which was then converted into area output using an electric energy conversion factor. This research aims to compare the energy efficiency of solar PV systems and solar thermal systems. Results: Using the conversion formula between electrical and thermal energy, we can compare the energy output of solar heating systems and solar photovoltaic systems. The comparative study draws upon data from February 2021 to February 2023, wherein the solar heating system generated an average of 2.54 kWh of energy per panel per day, while the solar photovoltaic system produced 1.17 kWh of energy per panel per day, resulting in a difference of approximately 2.17 times between the two systems. Conclusions: After conducting statistical analysis and comparisons, it was found that solar thermal heating systems offer higher energy and greater benefits than solar photovoltaic systems. Furthermore, an examination of literature data and simulations of the energy and economic benefits of solar thermal water systems and solar-assisted heat pump systems revealed that solar thermal water systems have higher energy density values, shorter recovery periods, and lower power consumption than solar-assisted heat pump systems. Through monitoring and empirical research in this study, it has been concluded that a heat pump-assisted solar thermal water system represents a relatively superior energy-saving and carbon-reducing solution for medical institutions. Not only can this system help reduce overall electricity consumption and the use of fossil fuels, but it can also provide more effective heating solutions.

Keywords: sustainable development, energy conservation, carbon reduction, renewable energy, heat pump system

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Authors: Massimo Mozzon, Nadia Raffaelli

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Proteases from herbs, woody plants, and trees are exploited for cheesemaking in several countries, especially in South Europe and West Africa. Particularly, “thistles” belonging to several genera within the Asteraceae family (Cynara, Silybum, Centaurea, Carlina, Cirsium, Onopordum) are traditionally used in Mediterranean countries for clotting raw ewe’s and goat’s milk. For the first time, the clotting performance of an aqueous extract from flowers of Onopordum tauricum Willd. (Taurian thistle, bull cottonthistle) were tested in milk of different origin (cow, goat, ewe). The vegetable material was collected in the Central Apennines range, between the Marche and Umbria regions. A response surface methodology (RSM) approach was used to study the effect of the curdling variables (temperature, pH, amount of enzymatic extract) on the technological performance of the thistle extract. A three-step procedure for the purification of the enzyme (ammonium sulphate precipitation, gel filtration and ion-exchange chromatography) was also carried out. The milk clotting activity (MCA) of O. tauricum crude extracts was strongly affected by temperature, pH and by the interaction between these two variables, according to a second-order response surface model, while the milk/coagulant ratio did not affect in a significant way the clotting properties. Experimental data showed that the addition of 10 mM CaCl2 reduced the clotting time of ewe’s, goat’s, and cow’s milk by about 3-fold, 8-fold, and 14-fold, respectively, at 35°C and pH 6.7-6.8. After purification, an enzymatic preparation very close to homogeneity was obtained, which showed a major band at about 30 kDa when analyzed by SDS-PAGE. The identity of the enzyme as an aspartic protease was confirmed by inhibition studies. Cheese-making trials were carried out to check the scale-up (1 to 5 L of milk; 37 °C; 10 mM CaCl2 fortification) and set the recipe: 35-45% of curd yields were recorded, according to curd cutting and pressing.

Keywords: milk clotting activity, Onopordum tauricum, plant proteases, vegetable rennet

Procedia PDF Downloads 159

Authors: M. A. Wijewardane, S. A. N. C. Sudasinghe, H. K. G. Punchihewa, W. K. D. L. Wickramasinghe, S. A. Philip, M. R. S. U. Kumara

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Visual comfort is one of the major parameters that can be taken to measure the human comfort in any environment. If the provided illuminance level in a working environment does not meet the workers visual comfort, it will lead to eye-strain, fatigue, headache, stress, accidents and finally, poor productivity. However, improvements in lighting do not necessarily mean that the workplace requires more light. Unnecessarily higher illuminance levels will also cause poor visual comfort and health risks. In addition, more power consumption on lighting will also result in higher energy costs. So, during this study, visual comfort and the illuminance requirement for the workers in textile/apparel industry were studied to perform different tasks (i.e. cutting, sewing and knitting) at their workplace. Experimental studies were designed to identify the optimum illuminance requirement depending upon the varied fabric colour and type and finally, energy saving potentials due to controlled illuminance level depending on the workforce requirement were analysed. Visual performance of workers during the sewing operation was studied using the ‘landolt ring experiment’. It was revealed that around 36.3% of the workers would like to work if the illuminance level varies from 601 lux to 850 lux illuminance level and 45.9% of the workers are not happy to work if the illuminance level reduces less than 600 lux and greater than 850 lux. Moreover, more than 65% of the workers who do not satisfy with the existing illuminance levels of the production floors suggested that they have headache, eye diseases, or both diseases due to poor visual comfort. In addition, findings of the energy analysis revealed that the energy-saving potential of 5%, 10%, 24%, 8% and 16% can be anticipated for fabric colours, red, blue, yellow, black and white respectively, when the 800 lux is the prevailing illuminance level for sewing operation.

Keywords: Landolt Ring experiment, lighting energy consumption, illuminance, textile and apparel industry, visual comfort

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Authors: Fatema-Tuz-Zohra Khanam, Ali Al-Naji, Asanka G. Perera, Kim Gibson, Javaan Chahl

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Conventional contact-based vital signs monitoring sensors such as pulse oximeters or electrocardiogram (ECG) may cause discomfort, skin damage, and infections, particularly in neonates with fragile, sensitive skin. Therefore, remote monitoring of the vital sign is desired in both clinical and non-clinical settings to overcome these issues. Camera-based vital signs monitoring is a recent technology for these applications with many positive attributes. However, there are still limited camera-based studies on neonates in a clinical setting. In this study, the heart rate (HR) and respiratory rate (RR) of eight infants at the Neonatal Intensive Care Unit (NICU) in Flinders Medical Centre were remotely monitored using a digital camera applying color and motion-based computational methods. The region-of-interest (ROI) was efficiently selected by incorporating an image decomposition method. Furthermore, spatial averaging, spectral analysis, band-pass filtering, and peak detection were also used to extract both HR and RR. The experimental results were validated with the ground truth data obtained from an ECG monitor and showed a strong correlation using the Pearson correlation coefficient (PCC) 0.9794 and 0.9412 for HR and RR, respectively. The RMSE between camera-based data and ECG data for HR and RR were 2.84 beats/min and 2.91 breaths/min, respectively. A Bland Altman analysis of the data also showed a close correlation between both data sets with a mean bias of 0.60 beats/min and 1 breath/min, and the lower and upper limit of agreement -4.9 to + 6.1 beats/min and -4.4 to +6.4 breaths/min for both HR and RR, respectively. Therefore, video camera imaging may replace conventional contact-based monitoring in NICU and has potential applications in other contexts such as home health monitoring.

Keywords: neonates, NICU, digital camera, heart rate, respiratory rate, image decomposition

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Authors: M. Invigorito, G. Elia, M. Panelli

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Hybrid propulsion combines beneficial properties of both solid and liquid rockets, such as multiple restarts, throttability as well as simplicity and reduced costs. A nitrous oxide (N2O)/paraffin-based hybrid rocket engine demonstrator is currently under development at the Italian Aerospace Research Center (CIRA) within the national research program HYPROB, funded by the Italian Ministry of Research. Nitrous oxide belongs to the class of self-pressurizing propellants that exhibit a high vapor pressure at standard ambient temperature. This peculiar feature makes those fluids very attractive for space rocket applications because it avoids the use of complex pressurization systems, leading to great benefits in terms of weight savings and reliability. To avoid feed-system-coupled instabilities, the phase change is required to occur through the injectors. In this regard, the oxidizer is stored in liquid condition while target chamber pressures are designed to lie below vapor pressure. The consequent cavitation and flash vaporization constitute a remarkably complex phenomenology that arises great modelling challenges. Thus, it is clear that the design of the injection system is fundamental for the full exploitation of hybrid rocket engine throttability. The Analytical Hierarchy Process has been used to select the injection architecture as best compromise among different design criteria such as functionality, technology innovation and cost. The impossibility to use engineering simplified relations for the dimensioning of the injectors led to the needs of applying a numerical approach based on OpenFOAM®. The numerical tool has been validated with selected experimental data from literature. Quantitative, as well as qualitative comparisons are performed in terms of mass flow rate and pressure drop across the injector for several operating conditions. The results show satisfactory agreement with the experimental data. Modeling assumptions, together with their impact on numerical predictions are discussed in the paper. Once assessed the reliability of the numerical tool, the injection plate has been designed and sized to guarantee the required amount of oxidizer in the combustion chamber and therefore to assure high combustion efficiency. To this purpose, the plate has been designed with multiple injectors whose number and diameter have been selected in order to reach the requested mass flow rate for the two operating conditions of maximum and minimum thrust. The overall design has been finally verified through three-dimensional computations in cavitating non-reacting conditions and it has been verified that the proposed design solution is able to guarantee the requested values of mass flow rates.

Keywords: hybrid rocket, injection system design, OpenFOAM®, cavitation

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Authors: Md. Abdul Kader, Md. Akiz Uddin

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The Islamic banking system is based on the Islamic shariah principles. Islamic banking is set up to avoid riba (interest)--which is prohibited in Islam-- and to prevent unscrupulous practices and participate actively in achieving the welfare-oriented Islamic economy. In the process of offering Islamic banking services, practitioners have been facing several challenges. Out of many challenges, this paper particularly highlights the need for a centralized legal framework for Islamic banks that should be compliant with the shariah law. The researchers employed a qualitative method to collect case studies from high-profile Islamic Bankers and analyzed respective legal documents and policy papers to conduct the study. This study investigates the Shariah Governance Framework (SGF), amended Banking Companies Act, 1991 (Act No. 14 of 1991), and the Shariah Supervisory Board (SSB) of Islamic banks in Bangladesh to evaluate how legal framework supervise and/or monitor Islamic banking system under the jurisdiction of shariah law. The study reveals that the Shariah governance system in Bangladesh is mainly voluntary rather than regulatory, and there is an absence of full-fledged SGF. Though there is no complete Islamic Banking Act for controlling, guiding, and supervising the Islamic banks in Bangladesh, some Islamic banking provisions have already been incorporated in the amended Banking Companies Act, 1991 (Act No. 14 of 1991). Bangladesh Bank did not set up any separate Department at its Head Office to control, guide and supervise the operation of the Islamic banks. So, ensuring the implementation of Shariah principles concurrent with the legal framework of banking policies is recommended in this study. This study also prescribes that the government should enact a law or policy for the operations of Islamic banks in order to improve the Islamic Banking system of Bangladesh. In addition, the central bank can set up a Central Shariah Supervisory Board (CSSB) or authorize the existing Central Shariah Board for Islamic Banks of Bangladesh (CSBIB) to supervise and monitor overall activities of Islamic banks and resolve the disputes among the stakeholders concerning the Shariah issues of Islamic banks.

Keywords: islamic banking, shariah law, banking policies, shariah governance framework (SGF)

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Authors: Anjana R. Menon, Anjana Bhasi

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Development of highways and railways play crucial role in a nation’s economic growth. While rigid concrete pavements are durable with high load bearing characteristics, growing economies mostly rely on flexible pavements which are easier in construction and more economical. The strength of flexible pavement is based on the strength of subgrade and load distribution characteristics of intermediate granular layers. In this scenario, to simultaneously meet economy and strength criteria, it is imperative to strengthen and stabilize the load transferring layers, namely subbase and base. Geosynthetic reinforcement in planar and cellular forms have been proven effective in improving soil stiffness and providing a stable load transfer platform. Studies have proven the relative superiority of cellular form-geocells over planar geosynthetic forms like geogrid, owing to the additional confinement of infill material and pocket effect arising from vertical deformation. Hence, the present study investigates the efficiency of geocells over single/multiple layer geogrid reinforcements by a series of three-dimensional model analyses of a flexible pavement section under a standard repetitive wheel load. The stress transfer mechanism and deformation profiles under various reinforcement configurations are also studied. Geocell reinforcement is observed to take up a higher proportion of stress caused by the traffic loads compared to single and double-layer geogrid reinforcements. The efficiency of single geogrid reinforcement reduces with an increase in embedment depth. The contribution of lower geogrid is insignificant in the case of the double-geogrid reinforced system.

Keywords: Geocell, Geogrid, Flexible Pavement, Repetitive Wheel Load, Numerical Analysis

Procedia PDF Downloads 75