Search results for: computer- supported collaborative learning

Authors: Hamid Gholami

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During the years, the language teaching methods have been the offshoots of schools of thought in psychology. The methods were mainly influenced by their contemporary psychological approaches, as Audiolingualism was based on behaviorism and Communicative Language Teaching on constructivism. In 1950s, the text books were full of repetition exercises which were encouraged by Behaviorism. In 1980s they got filled with communicative exercises as suggested by constructivism. The trend went on to nowadays that sees no specific method as prevalent since none of the schools of thought seem to be illustrative of the complexity in human being learning. But some changes can be notable; some textbooks are giving more and more space to repetition exercises at least to enhance some aspects of language proficiency, namely collocations, rhythm and intonation, and conversation models. These changes may mark the reemergence of one of the once widely accepted schools of thought in psychology; behaviorism.

Keywords: language teaching methods, psychology, schools of thought, Behaviorism

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Authors: Laima Zakaraite, Vaidas Morkevicius

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The COVID-19 pandemic brought important and pressing challenges for politicians around the world. Governments, parliaments, and political leaders had to make quick decisions about containment of the pandemic, usually without clear knowledge about the factual spread of the virus, the possible expected speed of spread, and levels of mortality. Opinions of experts were also divided, as some advocated for ‘herd immunity’ without closing down the economy and public life, and others supported the idea of strict lockdown. The debates about measures of pandemic containment were heated and involved strong moral tensions with regard to the possible outcomes. This paper proposes to study the manifestations of moral imagination in the political debates regarding the COVID-19 pandemic. Importantly, moral imagination is associated with twofold abilities of a decision-making actor: the ability to discern the moral aspects embedded within a situation and the ability to envision a range of possibilities alternative solutions to the situation from a moral perspective. The concept was most thoroughly investigated in business management studies. However, its relevance for the study of political decision-making is also rather clear. The results of the study show to what extent politicians are able to discern the wide range of moral issues related to a situation (in this case, consequences of COVID-19 pandemic in a country) and how broad (especially, from a moral perspective) are discussions of the possible solutions proposed for solving the problem (situation). Arguably, political discussions and considerations are broader and affected by a wider and more varied range of actors and ideas compared to decision making in the business management sector. However, the debates and ensuing solutions may also be restricted by ideological maxims and advocacy of special interests. Therefore, empirical study of policy proposals and their debates might reveal the actual breadth of moral imagination in political discussions. For this purpose, we carried out the qualitative study of the parliamentary debates related to the COVID-19 pandemic in Lithuania during the first wave (containment of which was considered very successful) and at the beginning and consequent acceleration of the second wave (when the spread of the virus became uncontrollable).

Keywords: decision making, moral imagination, political debates, political decision

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Authors: M. Yaqoob, C. S. O’Neill, S. Faraj, C. L. O’Neill

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This paper presents the preliminary findings from a study exploring nurse’s contributions to end of life decisions and to the care of dying patients in ICU units in the Kingdom of Bahrain. The process of dying is complex as medical clinicians are frequently unable to say with certainty when death will occur. It is generally accepted that end of life care begins when it is possible to know that death is imminent. Nurses do not make medical treatment decisions when caring for a dying patient. There are, however, many other types of decisions made when a patient is approaching the end of life and nurses are either formally or informally part of these decision making processes. This study explored nurses care practices at the end of life, in two ICU units in large hospitals in the Kingdom of Bahrain. The research design was a grounded theory approach. Ten nurses participated, six of whom were Bahraini nationals and four were Indian. A core category death avoidance talk was supported by three major subcategories, degrees of involvement in decision making; signalling and creating an awareness of death; care shifting from dying patients to family. Despite nurses asserting that they carried out the orders of doctors and had no role in decision making processes at end of life this study showed that there were degrees of nurse involvement. Doctors frequently discussed the patient’s clinical condition with nurses and also sought information regarding the family. Information about the family was of particular relevance if the doctor was considering a DNR order, which the nurses equated with dying. Families were not always informed when a DNR decision was made. When families were not informed the nurses engaged in sophisticated rituals signalling and creating awareness to family members that the death of their loved one was near. This process also involved a subtle shifting of care from the dying patient to the family. This seminar paper will focus particularly on how nurses signal and create an awareness of death in an ICU setting. The findings suggest that despite the avoidance of death talk in the ICU nurses indirectly convey and create an awareness that death is near to family members.

Keywords: decision making, dying patients, end of life, intensive care unit

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Authors: Muhammad Abdul Basit Memon

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The importance of organizational knowledge sharing and knowledge management has been documented in numerous research studies in available literature, since knowledge sharing has been recognized as a founding pillar for superior organizational performance and a source of gaining competitive advantage. Built on this, most of the successful organizations perceive knowledge management and knowledge sharing as a concern of high strategic importance and spend huge amounts on the effective management and sharing of organizational knowledge. However, despite some very serious endeavors, many firms fail to capitalize on the benefits of knowledge sharing because of being unaware of the individual characteristics, interpersonal, organizational and contextual factors that influence knowledge sharing; simply the antecedent to knowledge sharing. The extant literature on antecedents to knowledge sharing, offers a range of antecedents mentioned in a number of research articles and research studies. Some of the previous studies about antecedents to knowledge sharing, studied antecedents to knowledge sharing regarding inter-organizational knowledge transfer; others focused on inter and intra organizational knowledge sharing and still others investigated organizational factors. Some of the organizational antecedents to KS can relate to the characteristics and underlying aspects of knowledge being shared e.g., specificity and complexity of the underlying knowledge to be transferred; others relate to specific organizational characteristics e.g., age and size of the organization, decentralization and absorptive capacity of the firm and still others relate to the social relations and networks of organizations such as social ties, trusting relationships, and value systems. In the same way some researchers have highlighted on only one aspect like organizational commitment, transformational leadership, knowledge-centred culture, learning and performance orientation and social network-based relationships in the organizations. A bulk of the existing research articles on antecedents to knowledge sharing has mainly discussed organizational or environmental factors affecting knowledge sharing. However, the focus, later on, shifted towards the analysis of individuals or personal determinants as antecedents for the individual’s engagement in knowledge sharing activities, like personality traits, attitude and self efficacy etc. For example, employees’ goal orientations (i.e. learning orientation or performance orientation is an important individual antecedent of knowledge sharing behaviour. While being consistent with the existing literature therefore, the antecedents to knowledge sharing can be classified as being individual and organizational. This paper is an endeavor to discuss a conceptual framework of the individual and organizational antecedents to knowledge sharing in the light of the available literature and empirical evidence. This model not only can help in getting familiarity and comprehension on the subject matter by presenting a holistic view of the antecedents to knowledge sharing as discussed in the literature, but can also help the business managers and especially human resource managers to find insights about the salient features of organizational knowledge sharing. Moreover, this paper can help provide a ground for research students and academicians to conduct both qualitative as well and quantitative research and design an instrument for conducting survey on the topic of individual and organizational antecedents to knowledge sharing.

Keywords: antecedents to knowledge sharing, knowledge management, individual and organizational, organizational knowledge sharing

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Authors: Pennapa Palapin

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This research sought to study the traditional local wisdom and study the promotion and dissemination of traditional local wisdom in order to find the forms of promotion and dissemination of traditional local wisdom to create occupations among the elderly at Nonmueng Community, Muang Sub-District, Baan Dung District, UdonThani Province. The criterion used to select the research sample group was, being a person having a role involved in the promotion and dissemination of traditional local wisdom to create occupations among the elderly at Nonmueng Community, Muang Sub-District, Baan Dung District, UdonThani Province; being an experienced person whom the residents of Nonmueng Community find trustworthy; and having lived in Nonmueng Community for a long time so as to be able to see the development and change that occurs. A total of 16 people were selected. Data was gathered as a qualitative study, through semi-structured in-depth interviews. The collected data was then summarised and discussed according to the research objectives. Finally, the data was presented in a narrative format. Results found that the identifying traditional local wisdom of the community (which grew from the residents’ experience and beneficial usage in daily life, passed down from generation to generation) was the weaving of cloth and basketry. As for the manner of promotion and dissemination of traditional local wisdom, the skills were passed down through teaching by example to family members, relatives and others in the community. This was done by the elders or elderly members of the community. For the promotion and dissemination of traditional local wisdom to create occupations among the elderly, the traditional local wisdom should be supported in every way through participation of the community members. For example, establish a museum of traditional local wisdom for the collection of traditional local wisdom in various fields, both in the past and at present. This would be a source of pride for the community, in order to make traditional local wisdom widely known and to create income for the community’s elderly. Additional ways include exhibitions of products made by traditional local wisdom, finding both domestic and international markets, as well as building both domestic and international networks aiming to find opportunities to market products made by traditional local wisdom.

Keywords: traditional local wisdom, occupation, elderly, community

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Authors: Suharni Mohamad Suharni Mohamad, Nurul Izzati Hamzan Nurul Izzati Hamzan, Norhayu Abdul Rahman Norhayu Abdul Rahman, Siti Suraiya Md Noor Siti Suraiya Md Noor

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Human papillomavirus (HPV) is an important risk factor for development of oral cancer. HPV16 is the most common type found in HPV-positive squamous cell carcinoma. In the present study, we established a real-time loop-mediated isothermal amplification (real-time LAMP) for detection of HPV16. A set of six primers was specially designed to recognize eight distinct sequences of HPV16-E6. Detection and quantification was achieved by real-time monitoring using a real-time turbidimeter based on threshold time required for turbidity in the LAMP reaction. LAMP reagents (MgSO4, dNTPs, Bst polymerase concentrations) and various incubation times and temperatures were optimized. The sensitivity was determined using 10-fold serial dilutions of HPV16 standard strain. The specificity of was evaluated using other HPV genotypes. The optimized method was established with specifically designed primers by real-time detection in approximately 30 min at 65°C. The limit of detection of HPV16 using the LAMP assay was 10 pg/ml that could be detected in 30 min. The LAMP assay was 10 times more sensitive than the conventional PCR in detecting HPV16. No cross-reactivity with other HPV genotypes was observed. This quantitative real-time LAMP assay may improve diagnostic potential for the detection and quantification of HPV16 in clinical samples and epidemiological studies due to its rapidity, simplicity, high sensitivity and specificity. This assay will be further evaluated with HPV DNAs of saliva from patients with oral squamous cell carcinoma. Acknowledgement: This study was financially supported by the ScienceFund Grant, Ministry of Science, Technology and Innovation (305/PPSG/6113219).

Keywords: Oral Squamous Cell Carcinoma (OSCC), Human Papillomavirus 16 (HPV16), Loop-Mediated Isothermal Amplification (LAMP), rapid detection

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Authors: Aikaterini Tavoulari, Mike Richardson

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Objective: This abstract presents a multisensory participatory design project, inspired by a deafblind PhD student's ambition to climb Mount Everest. The project aims to explore accessible routes for filmmaking and video content creation, catering to the needs of individuals with hearing and sight loss. By engaging participants from the Southwest area of England, recruited through multiple networks, the project seeks to gather qualitative data and insights to inform the development of inclusive media practices. Design: It will be a community-based participatory research design. The workshop will feature various stations that stimulate different senses, such as scent, touch, sight, hearing as well as movement. Participants will have the opportunity to engage with these multisensory experiences, providing valuable feedback on their effectiveness and potential for enhancing accessibility in filmmaking and video content. Methods: Brief semi-structured interviews will be conducted to collect qualitative data, allowing participants to share their perspectives, challenges, and suggestions for improvement. The participatory design approach emphasizes the importance of involving the target audience in the creative process. By actively engaging individuals with hearing and sight loss, the project aims to ensure that their needs and preferences are central to the development of accessible filmmaking techniques and video content. This collaborative effort seeks to bridge the gap between content creators and diverse audiences, fostering a more inclusive media landscape. Results: The findings from this study will contribute to the growing body of research on accessible filmmaking and video content creation. Via inductive thematic analysis of the qualitative data collected through interviews and observations, the researchers aim to identify key themes, challenges, and opportunities for creating engaging and inclusive media experiences for deafblind audiences. The insights will inform the development of best practices and guidelines for accessible filmmaking, empowering content creators to produce more inclusive and immersive video content. Conclusion: The abstract targets the hybrid International Conference for Disability and Diversity in Canada (January 2025), as this platform provides an excellent opportunity to share the outcomes of the project with a global audience of researchers, practitioners, and advocates working towards inclusivity and accessibility in various disability domains. By presenting this research at the conference in person, the authors aim to contribute to the ongoing discourse on disability and diversity, highlighting the importance of multisensory experiences and participatory design in creating accessible media content for the deafblind community and the community with sensory impairments more broadly.

Keywords: vision impairment, hearing impairment, deafblindness, accessibility, filmmaking

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Authors: Danilo López, Nelson Vera, Luis Pedraza

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This paper analyzes fundamental ideas and concepts related to neural networks, which provide the reader a theoretical explanation of Long Short-Term Memory (LSTM) networks operation classified as Deep Learning Systems, and to explicitly present the mathematical development of Backward Pass equations of the LSTM network model. This mathematical modeling associated with software development will provide the necessary tools to develop an intelligent system capable of predicting the behavior of licensed users in wireless cognitive radio networks.

Keywords: neural networks, multilayer perceptron, long short-term memory, recurrent neuronal network, mathematical analysis

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Authors: N. Smaoui, B. Chentouf

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The boundary stabilization problem of the rotating disk-beam system is a topic of interest in research studies. This system involves a flexible beam attached to the center of a disk, and the control and stabilization of this system have been extensively studied. This research focuses on the case where the center of mass is fixed in an inertial frame, and the rotation of the center is non-uniform. The system is represented by a set of nonlinear coupled partial differential equations and ordinary differential equations. The boundary stabilization problem of this system via a delayed boundary control is considered. We assume that the boundary control is either of a force type control or a moment type control and is subject to the presence of a constant time-delay. The aim of this research is threefold: First, we demonstrate that the rotating disk-beam system is well-posed in an appropriate functional space. Then, we establish the exponential stability property of the system. Finally, we provide numerical simulations that illustrate the theoretical findings. The research utilizes the semigroup theory to establish the well-posedness of the system. The resolvent method is then employed to prove the exponential stability property. Finally, the finite element method is used to demonstrate the theoretical results through numerical simulations. The research findings indicate that the rotating disk-beam system can be stabilized using a boundary control with a time delay. The proof of stability is based on the resolvent method and a variation of constants formula. The numerical simulations further illustrate the theoretical results. The findings have potential implications for the design and implementation of control strategies in similar systems. In conclusion, this research demonstrates that the rotating disk-beam system can be stabilized using a boundary control with time delay. The well-posedness and exponential stability properties are established through theoretical analysis, and these findings are further supported by numerical simulations. The research contributes to the understanding and practical application of control strategies for flexible structures, providing insights into the stability of rotating disk-beam systems.

Keywords: rotating disk-beam, delayed force control, delayed moment control, torque control, exponential stability

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Authors: Boris Bajer, Andrea Havranova, Miroslav Vlcek, Richard Imrich, Adela Penesova

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Lifestyle interventions can prevent the deterioration of impaired glucose tolerance to manifest type 2 diabetes, and also prevent cardiovascular diseases, as it showed many studies (the Finnish Diabetes Prevention Study, Diabetes Prevention Program (DPP), . the China Da Qing Diabetes Prevention Study, etc.) Therefore the aim of our study was to compare the effect of intensified lifestyle intervention on cardiometabolic parameters. Methods: It is an ongoing randomized interventional clinical study (NCT02325804) focused on the reduction of body weight/fat. Intervention: hypocaloric diet (30% restriction of calories) and physical activity 150 minutes/week. Before and after 8 weeks of intervention all patients underwent complete medical examination (measurement of physical fitness, resting metabolic rate (RMR), body composition analysis, oral glucose tolerance test, parameters of lipid metabolism, and other cardiometabolic risk factors. Results: So far 39 patients finished the intervention. The average reduction of body weight was 6,8 + 4,9 kg (0-15 kg; p=0,0006), accompanied with significant reduction of body fat percentage (p ≤ 0,0001), amount of fat mass (p=0,03), waist circumference (p=0.02). Amount of lean mass and RMR remained unchanged. Heart rate (p=0,02), systolic and diastolic blood pressure was reduced (p=0,01 p=0,02 resp.) as well as insulin sensitivity was improved. Lipid parameters also changed - cholesterol, LDL decreased (p=0,05, p=0,04 resp.), while triglycerides showed tendency to decrease (p=0,055). Liver function improved, alanine aminotrasnferase (ALT) were reduced (p=0,01). Physical fitness significantly improved (as measure VO2 max (p=0,02). Conclusion: Results of our study are in line with previous results about the beneficial effect of intensive lifestyle changes on the reduction of cardiometabolic risk factors and improvement of liver function. Supported by grants APVV 15-0228; VEGA 2/0161/16

Keywords: obesity, weight loss, diet lipids, blood pressure, liver enzymes

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Authors: Lee Jeong Min, Lee Mi Hee, Eo Yang Dam

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Geospatial feature extraction is a very important issue in the remote sensing research. In the meantime, the image classification based on statistical techniques, but, in recent years, data mining and machine learning techniques for automated image processing technology is being applied to remote sensing it has focused on improved results generated possibility. In this study, artificial neural network and decision tree technique is applied to classify the high-resolution satellite images, as compared to the MLC processing result is a statistical technique and an analysis of the pros and cons between each of the techniques.

Keywords: remote sensing, artificial neural network, decision tree, maximum likelihood classification

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Authors: Aline V. Arroteia, Gustavo G. Do Amaral, Simone Z. Kikuti, Norberto C. S. Moura, Silvio B. Melhado

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Despite the significant advances made by the construction industry in recent years, the crystalized absence of integration between the design and construction phases is still an evident and costly problem in building construction. Globally, the construction industry has sought to adopt collaborative practices through new technologies to mitigate impacts of this fragmented process and to optimize its production. In this new technological business environment, professionals are required to develop new methodologies based on the notion of collaboration and integration of information throughout the building lifecycle. This scenario also represents the industry’s reality in developing nations, and the increasing need for overall efficiency has demanded new educational alternatives at the undergraduate and post-graduate levels. In countries like Brazil, it is the common understanding that Architecture, Engineering and Building Construction educational programs are being required to review the traditional design pedagogical processes to promote a comprehensive notion about integration and simultaneity between the phases of the project. In this context, the coherent inclusion of computation design to all segments of the educational programs of construction related professionals represents a significant research topic that, in fact, can affect the industry practice. Thus, the main objective of the present study was to comparatively measure the effectiveness of the Building Information Modeling courses offered by the University of Sao Paulo, the most important academic institution in Brazil, at the Schools of Architecture and Civil Engineering and the courses offered in well recognized BIM research institutions, such as the School of Design in the College of Architecture of the Georgia Institute of Technology, USA, to evaluate the dissemination of BIM knowledge amongst students in post graduate level. The qualitative research methodology was developed based on the analysis of the program and activities proposed by two BIM courses offered in each of the above-mentioned institutions, which were used as case studies. The data collection instruments were a student questionnaire, semi-structured interviews, participatory evaluation and pedagogical practices. The found results have detected a broad heterogeneity of the students regarding their professional experience, hours dedicated to training, and especially in relation to their general knowledge of BIM technology and its applications. The research observed that BIM is mostly understood as an operational tool and not as methodological project development approach, relevant to the whole building life cycle. The present research offers in its conclusion an assessment about the importance of the incorporation of BIM, with efficiency and in its totality, as a teaching method in undergraduate and graduate courses in the Brazilian architecture, engineering and building construction schools.

Keywords: building information modeling (BIM), BIM education, BIM process, design teaching

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Authors: Firas M. Tuaimah

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This paper presents an Artificial Neural Network based approach for short-term load forecasting and exactly for two days ahead. Two seasons have been discussed for Iraqi power system, namely summer and winter; the hourly load demand is the most important input variables for ANN based load forecasting. The recorded daily load profile with a lead time of 1-48 hours for July and December of the year 2012 was obtained from the operation and control center that belongs to the Ministry of Iraqi electricity. The results of the comparison show that the neural network gives a good prediction for the load forecasting and for two days ahead.

Keywords: short-term load forecasting, artificial neural networks, back propagation learning, hourly load demand

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Authors: Amel Bouaziz, Seddik Khennouf, Mussa Abu Zarga, Shtayway Abdalla, Saliha Djidel, Assia Bentahar, Saliha Dahamna, Smain Amira

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The present study aimed to evaluate the hypotensive and the in vitro antioxidant activities of Crataegus azarolus L. (Rosaceae), a plant widely used as natural remedy for hypertension in folk medicine. The antioxidant potential of methanolic extract (ME)and its three fractions of Chloroform (CHE), ethyl acetate (EAE)and water (AqE) have been investigated using several assays, including the DPPH scavenging, ABTS scavenging, hydroxyl radical scavenging. Inhibition of lipid peroxidation was performed by the β-carotene bleaching assay, ferric thiocyanate method and thiobarburic acid method. Total phenolic and total flavonoid contents of the extracts were estimated using Folin-Chiocalteu reagent and AlCl3, respectively. EAE extract showed the highest polyphenolic and flavonoids contents (396,04±1.20 mg GAE/g of dry extract and 32,73 ± 0.03mg QE/g of dry extract) respectively. Similarly, this extract possessed the highest scavenging activity for DPPH radical (IC 50 = 0,006±0,0001mg /ml), ABTS radical (IC50=0.0035±0,0007 mg/ml) and hydroxyl radical(IC 50=0,283± 0.01 mg/ml). In addition, the EAE exhibited the highest antioxidant activity in the inhibition of linoleic acid/ß-carotene coupled oxidation (89,21%), lipid peroxidation in the ferric thiocyanate(FTC) method (90.13%), and thio-barbituric acid (TBA) method (74.23%). Intravenous administration of Me and EAE decreased mean arterial blood pressure, systolic and diastolic blood pressure in anesthetized rats dose-dependently, at the dose range of 0.4 to 12 mg/kg. The mean arterial blood pressure dropped by 27.58 and 39.37% for ME and EAE, respectively. In conclusion, The present study supported the significant potential to use C. azarolus by-products as a source of natural antioxidants and provides scientific justification for its traditional uses as cardio-protective and anti-hypertensive remedy.

Keywords: Crataegus azarolus, polyphenols, flavonoids, hypertension, antioxidant activity, free radicals, peroxidation

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Authors: Netasha Shaikh, Bryony Wood, Demitra Tsivos, Michael Knight, Risto Kauppinen, Elizabeth Coulthard

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Background: Effective treatment of dementia will require early diagnosis, before significant brain damage has accumulated. Memory loss is an early symptom of Alzheimer’s disease (AD). The hippocampus, a brain area critical for memory, degenerates early in the course of AD. The hippocampus comprises several subfields. In contrast to healthy aging where CA3 and dentate gyrus are the hippocampal subfields with most prominent atrophy, in AD the CA1 and subiculum are thought to be affected early. Conventional clinical structural neuroimaging is not sufficiently sensitive to identify preferential atrophy in individual subfields. Here, we will explore the sensitivity of new magnetic resonance imaging (MRI) sequences designed to interrogate medial temporal regions as an early marker of Alzheimer’s. As it is likely a combination of tests may predict early Alzheimer’s disease (AD) better than any single test, we look at the potential efficacy of such imaging alone and in combination with standard and novel cognitive tasks of hippocampal dependent memory. Methods: 20 patients with mild cognitive impairment (MCI), 20 with mild-moderate AD and 20 age-matched healthy elderly controls (HC) are being recruited to undergo 3T MRI (with sequences designed to allow volumetric analysis of hippocampal subfields) and a battery of cognitive tasks (including Paired Associative Learning from CANTAB, Hopkins Verbal Learning Test and a novel hippocampal-dependent abstract word memory task). AD participants and healthy controls are being tested just once whereas patients with MCI will be tested twice a year apart. We will compare subfield size between groups and correlate subfield size with cognitive performance on our tasks. In the MCI group, we will explore the relationship between subfield volume, cognitive test performance and deterioration in clinical condition over a year. Results: Preliminary data (currently on 16 participants: 2 AD; 4 MCI; 9 HC) have revealed subfield size differences between subject groups. Patients with AD perform with less accuracy on tasks of hippocampal-dependent memory, and MCI patient performance and reaction times also differ from healthy controls. With further testing, we hope to delineate how subfield-specific atrophy corresponds with changes in cognitive function, and characterise how this progresses over the time course of the disease. Conclusion: Novel sequences on a MRI scanner such as those in route in clinical use can be used to delineate hippocampal subfields in patients with and without dementia. Preliminary data suggest that such subfield analysis, perhaps in combination with cognitive tasks, may be an early marker of AD.

Keywords: Alzheimer's disease, dementia, memory, cognition, hippocampus

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Authors: E. Al Daoud

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In many cases, theoretical treatments are available for models for which there is no perfect physical realization. In this situation, the only possible test for an approximate theoretical solution is to compare with data generated from a computer simulation. In this paper, Monte Carlo tools are used to study and compare the elementary particles models. All the experiments are implemented using 10000 events, and the simulated energy is 13 TeV. The mean and the curves of several variables are calculated for each model using MadAnalysis 5. Anomalies in the results can be seen in the muons masses of the minimal supersymmetric standard model and the two Higgs doublet model.

Keywords: Feynman rules, hadrons, Lagrangian, Monte Carlo, simulation

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Authors: Murtaza Hassan Sheikh, Ahmed A. A. AlSaleh, Naser H. N. Jasem

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Kuwait has not yet made its mark in the world of technology and research. Therefore, advancements have been made to fill in this gap. Since Robotics covers a wide variety of fields and helps innovation, efforts have been made to promote its education. Despite of the efforts made in Kuwait, robotics education is still on hold. The paper discusses the issues and obstacles in the implementation of robotics education in Kuwait and how a robotics kit “E-Robot” is making an impact in the Kuwait’s future education and innovation. Problems such as robotics competitions rather than education, complexity of robot programming and lack of organized open source platform are being addressed by the introduction of the E-Robot Kit in Kuwait. Due to its success since 2012 a total of 15 schools have accepted the Kit as a core subject, with 200 teaching it as an extracurricular activity.

Keywords: robotics education, Kuwait's education, e-robot kit, research and development, innovation and creativity

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Authors: Dmitry Fedoseyev

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The ultimate success of unmanned aerial vehicles (UAVs) depends largely on the effective control of their flight, especially in variable wind conditions. This paper investigates different approaches to selecting the optimal flight level to maximize the range of UAVs. We propose to consider methods based on mathematical models of atmospheric conditions, as well as the use of sensor data and machine learning algorithms to automatically optimize the flight level in real-time. The proposed approaches promise to improve the efficiency and range of UAVs in various wind conditions, which may have significant implications for the application of these systems in various fields, including geodesy, environmental surveillance, and search and rescue operations.

Keywords: drone, UAV, flight trajectory, wind-searching, efficiency

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Authors: Justin Woulfe

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Siloed logistics and supply chain management systems throughout the Department of Defense (DOD) has led to disparate approaches to modeling and simulation (M&S), a lack of understanding of how one system impacts the whole, and issues with “optimal” solutions that are good for one organization but have dramatic negative impacts on another. Many different systems have evolved to try to understand and account for uncertainty and try to reduce the consequences of the unknown. As the DoD undertakes expansive digital transformation initiatives, there is an opportunity to fuse and leverage traditionally disparate data into a centrally hosted source of truth. With a streamlined process incorporating machine learning (ML) and artificial intelligence (AI), advanced M&S will enable informed decisions guiding program success via optimized operational readiness and improved mission success. One of the current challenges is to leverage the terabytes of data generated by monitored systems to provide actionable information for all levels of users. The implementation of a cloud-based application analyzing data transactions, learning and predicting future states from current and past states in real-time, and communicating those anticipated states is an appropriate solution for the purposes of reduced latency and improved confidence in decisions. Decisions made from an ML and AI application combined with advanced optimization algorithms will improve the mission success and performance of systems, which will improve the overall cost and effectiveness of any program. The Systecon team constructs and employs model-based simulations, cutting across traditional silos of data, aggregating maintenance, and supply data, incorporating sensor information, and applying optimization and simulation methods to an as-maintained digital twin with the ability to aggregate results across a system’s lifecycle and across logical and operational groupings of systems. This coupling of data throughout the enterprise enables tactical, operational, and strategic decision support, detachable and deployable logistics services, and configuration-based automated distribution of digital technical and product data to enhance supply and logistics operations. As a complete solution, this approach significantly reduces program risk by allowing flexible configuration of data, data relationships, business process workflows, and early test and evaluation, especially budget trade-off analyses. A true capability to tie resources (dollars) to weapon system readiness in alignment with the real-world scenarios a warfighter may experience has been an objective yet to be realized to date. By developing and solidifying an organic capability to directly relate dollars to readiness and to inform the digital twin, the decision-maker is now empowered through valuable insight and traceability. This type of educated decision-making provides an advantage over the adversaries who struggle with maintaining system readiness at an affordable cost. The M&S capability developed allows program managers to independently evaluate system design and support decisions by quantifying their impact on operational availability and operations and support cost resulting in the ability to simultaneously optimize readiness and cost. This will allow the stakeholders to make data-driven decisions when trading cost and readiness throughout the life of the program. Finally, sponsors are available to validate product deliverables with efficiency and much higher accuracy than in previous years.

Keywords: artificial intelligence, digital transformation, machine learning, predictive analytics

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Authors: Kyungsuk Cho, Seungun Chae, Jihun Choi

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Elevators are examined as one of evacuation methods in super-tall buildings. However, data on the use of elevators for evacuation at a fire are extremely scarce. Therefore, a test to measure delay time in using an evacuation elevator was conducted. In the test, time taken to get on and get off an elevator was measured and the case in which people gave up boarding when the capacity of the elevator was exceeded was also taken into consideration. 170 men and women participated in the test, 130 of whom were young people (20 ~ 50 years old) and 40 were senior citizens (over 60 years old). The capacity of the elevator was 25 people and it travelled between the 2nd and 4th floors. A video recording device was used to analyze the test. An elevator at an ordinary building, not a super-tall building, was used in the test to measure delay time in getting on and getting off an elevator. In order to minimize interference from other elements, elevator platforms on the 2nd and 4th floors were partitioned off. The elevator travelled between the 2nd and 4th floors where people got on and off. If less than 20 people got on the elevator which was empty, the data were excluded. If the elevator carrying 10 passengers stopped and less than 10 new passengers got on the elevator, the data were excluded. Getting-on an empty elevator was observed 49 times. The average number of passengers was 23.7, it took 14.98 seconds for the passengers to get on the empty elevator and the load factor was 1.67 N/s. It took the passengers, whose average number was 23.7, 10.84 seconds to get off the elevator and the unload factor was 2.33 N/s. When an elevator’s capacity is exceeded, the excessive number of people should get off. Time taken for it and the probability of the case were measure in the test. 37% of the times of boarding experienced excessive number of people. As the number of people who gave up boarding increased, the load factor of the ride decreased. When 1 person gave up boarding, the load factor was 1.55 N/s. The case was observed 10 times, which was 12.7% of the total. When 2 people gave up boarding, the load factor was 1.15 N/s. The case was observed 7 times, which was 8.9% of the total. When 3 people gave up boarding, the load factor was 1.26 N/s. The case was observed 4 times, which was 5.1% of the total. When 4 people gave up boarding, the load factor was 1.03 N/s. The case was observed 5 times, which was 6.3% of the total. Getting-on and getting-off time data for people who can walk freely were obtained from the test. In addition, quantitative results were obtained from the relation between the number of people giving up boarding and time taken for getting on. This work was supported by the National Research Council of Science & Technology (NST) grant by the Korea government (MSIP) (No. CRC-16-02-KICT).

Keywords: evacuation elevator, super tall buildings, evacuees, delay time

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Authors: Benmoussa Dennai, H. Benslimane, A. Helmaoui

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Photo voltaic conversion is the direct conversion of electromagnetic energy into electrical energy continuously. This electromagnetic energy is the most solar radiation. In this work we performed a computer modelling using AMPS 1D optimization of hetero-junction solar cells GaInP/GaAs configuration for p/ n. We studied the influence of the thickness the base layer in the cell offers on the open circuit voltage, the short circuit current and efficiency.

Keywords: optimization, photovoltaic cell, GaInP / GaAs AMPS-1D, hetetro-junction

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Authors: Yanyan Wang

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This paper on second language teaching and learning uses conversation analysis (CA) approach and focuses on how second language learners of Chinese do repair when making clarification requests. In order to demonstrate their behavior in interaction, a comparison was made to study the differences between native speakers of Chinese with non-native speakers of Chinese. The significance of the research is to make second language teachers and learners aware of repair and how to seek clarification. Utilizing the methodology of CA, the research involved two sets of naturally occurring recordings, one of native speaker students and the other of non-native speaker students. Both sets of recording were telephone talks between students and teachers. There were 50 native speaker students and 50 non-native speaker students. From multiple listening to the recordings, the parts with repairs for clarification were selected for analysis which included the moments in the talk when students had problems in understanding or hearing the speaker and had to seek clarification. For example, ‘Sorry, I do not understand ‘and ‘Can you repeat the question? ‘were the parts as repair to make clarification requests. In the data, there were 43 such cases from native speaker students and 88 cases from non-native speaker students. The non-native speaker students were more likely to use repair to seek clarification. Analysis on how the students make clarification requests during their conversation was carried out by investigating how the students initiated problems and how the teachers repaired the problems. In CA term, it is called other-initiated self-repair (OISR), which refers to student-initiated teacher-repair in this research. The findings show that, in initiating repair, native speaker students pay more attention to mutual understanding (inter-subjectivity) while non-native speaker students, due to their lack of language proficiency, pay more attention to their status of knowledge (epistemic) switch. There are three major differences: 1, native Chinese students more often initiate closed-class OISR (seeking specific information in the request) such as repeating a word or phrases from the previous turn while non-native students more frequently initiate open-class OISR (not specifying clarification) such as ‘sorry, I don’t understand ‘. 2, native speakers’ clarification requests are treated by the teacher as understanding of the content while non-native learners’ clarification requests are treated by teacher as language proficiency problem. 3, native speakers don’t see repair as knowledge issue and there is no third position in the repair sequences to close repair while non-native learners take repair sequence as a time to adjust their knowledge. There is clear closing third position token such as ‘oh ‘ to close repair sequence so that the topic can go back. In conclusion, this paper uses conversation analysis approach to compare differences between native Chinese speakers and non-native Chinese learners in their ways of conducting repair when making clarification requests. The findings are useful in future Chinese language teaching and learning, especially in teaching pragmatics such as requests.

Keywords: conversation analysis (CA), clarification request, second language (L2), teaching implication

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Authors: Ashir Ahmed

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Peacekeeping is a collective responsibility of governments, law enforcement agencies, communities, families, and individuals. Moreover, the complex nature of peacekeeping activities requires a holistic and collaborative approach where various community sectors work together to form collective strategies that are likely to be more effective than strategies designed and delivered in isolation. Similarly, it is important to learn from past programs to evaluate the initiatives that have worked well and the areas that need further improvement. Review of recent peacekeeping initiatives suggests that there have been tremendous efforts and resources put in place to deal with the emerging threat of terrorism, radicalization and violent extremism through number of de-radicalization programs. Despite various attempts in designing and delivering successful programs for deradicalization, the threat of people being radicalized is growing more than ever before. This research reviews the prominent de-radicalization programs to draw an understanding of their strengths and weaknesses. Some of the weaknesses in the existing programs include. Inaccessibility: Limited resources, geographical location of potential participants (for offline programs), inaccessibility or inability to use various technologies (for online programs) makes it difficult for people to participate in de-radicalization programs. Timeliness: People might need to wait for a program on a set date/time to get the required information and to get their questions answered. This is particularly true for offline programs. Lack of trust: The privacy issues and lack of trust between participants and program organizers are another hurdle in the success of de-radicalization programs. The fear of sharing participants information with organizations (such as law enforcement agencies) without their consent led them not to participate in these programs. Generalizability: Majority of these programs are very generic in nature and do not cater the specific needs of an individual. Participants in these programs may feel that the contents are irrelevant to their individual situations and hence feel disconnected with purpose of the programs. To address the above-mentioned weaknesses, this research developed a framework that recommends some improvements in de-radicalization programs. One of the recommendations is to offer 24/7, secure, private and online hotline (also referred as helpline) for the people who have any question, concern or situation to discuss with someone who is qualified (a counsellor) to deal with people who are vulnerable to be radicalized. To make these hotline services viable and sustainable, the existing organizations offering support for depression, anxiety or suicidal ideation could additionally host these services. These helplines should be available via phone, the internet, social media and in-person. Since these services will be embedded within existing and well-known services, they would likely to get more visibility and promotion. The anonymous and secure conversation between a person and a counsellor would ensure that a person can discuss the issues without being afraid of information sharing with any third party – without his/her consent. The next stage of this project would include the operationalization of the framework by collaborating with other organizations to host de-radicalization hotlines and would assess the effectiveness of such initiatives.

Keywords: de-radicalization, framework, hotlines, peacekeeping

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Authors: Wan-Lin Tsai

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Speech act of requests is an important issue in the field of language learning and teaching because we cannot avoid making requesting in our daily life. This study examined whether or not the subjects who were freshmen and majored in German at Wenzao University of Languages were able to use the linguistic forms which they had learned from their course book Schritte International to make appropriate requests through dialogue completed tasks (DCT). The results revealed that the majority of the subjects were unable to use the forms to make appropriate requests in German due to the lack of explicit instructions. Furthermore, Chinese interference was observed in students' productions. Explicit instructions in speech acts are strongly recommended.

Keywords: Chinese interference, German pragmatics, German teaching, make appropriate requests in German, speech act of requesting

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Authors: Zhi-Zhong Chen, Jun-Hao Lu, Jr., Shih-Ying Chueh

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Based on Unified Theory of Acceptance and Use of Technology (UTAUT), the study investigates people’s intention on using smart phones. The study additionally incorporates two new variables: 'self-efficacy' and 'attitude toward using'. Samples are collected by questionnaire survey, in which 240 are valid. After Correlation Analysis, Reliability Test, ANOVA, t-test and Multiple Regression Analysis, the study finds that social impact and self-efficacy have positive effect on use intentions, and the use intentions also have positive effect on use behavior.

Keywords: [1] Ajzen & Fishbein (1975), “Belief, attitude, intention and behavior: An introduction to theory and research”, Reading MA: Addison-Wesley. [2] Bandura (1977) Self-efficacy: toward a unifying theory of behavioural change. Psychological Review , 84, 191–215. [3] Bandura( 1986) A. Bandura, Social foundations of though and action, Prentice-Hall. Englewood Cliffs. [4] Ching-Hui Huang (2005). The effect of Regular Exercise on Elderly Optimism: The Self-efficacy and Theory of Reasoned Action Perspectives.(Master's dissertation, National Taiwan Sport University, 2005).National Digital Library of Theses and Dissertations in Taiwan。 [5] Chun-Mo Wu (2007).The Effects of Perceived Risk and Service Quality on Purchase Intention - an Example of Taipei City Long-Term Care Facilities. (Master's dissertation, Ming Chuan University, 2007).National Digital Library of Theses and Dissertations in Taiwan. [6] Compeau, D.R., and Higgins, C.A., (1995) “Application of social cognitive theory to training for computer skills.”, Information Systems Research, 6(2), pp.118-143. [7] computer-self-efficacy and mediators of the efficacy-performance relationship. International Journal of Human-Computer Studies, 62, 737-758. [8] Davis et al(1989), “User acceptance of computer technology: A comparison of two theoretical models ”, Management Science, 35(8), p.982-1003. [9] Davis et al(1989), “User acceptance of computer technology:A comparison of two theoretical models ”, Management Science, 35(8), p.982-1003. [10] Davis, F.D. (1989). Perceived Usefulness, Perceived Ease of Use and User Acceptance of Information Technology. MIS Quarterly, 13(3), 319-340。 [11] Davis. (1989). Perceived Usefulness, Perceived Ease of Use, and User Acceptance of Information Technology. MIS Quarterly, 13(3), 319–340. doi:10.2307/249008 [12] Johnson, R. D. (2005). An empirical investigation of sources of application-specific [13] Mei-yin Hsu (2010).The Study on Attitude and Satisfaction of Electronic Documents System for Administrators of Elementary Schools in Changhua County.(Master's dissertation , Feng Chia University, 2010).National Digital Library of Theses and Dissertations in Taiwan. [14] Ming-Chun Hsieh (2010). Research on Parents’ Attitudes Toward Electronic Toys： The case of Taichung City.(Master's dissertation, Chaoyang University of Technology，2010).National Digital Library of Theses and Dissertations in Taiwan. [15] Moon and Kim（2001）. Extending the TAM for a World-Wide-Web context, Information and Management, v.38 n.4, p.217-230. [16] Shang-Yi Hu (2010).The Impacts of Knowledge Management on Customer Relationship Management – Enterprise Characteristicsand Corporate Governance as a Moderator.(Master's dissertation, Leader University, 2010)。National Digital Library of Theses and Dissertations in Taiwan. [17] Sheng-Yi Hung (2013, September10).Worldwide sale of smartphones to hit one billion IDC：Android dominate the market. ETtoday. Retrieved data form the available protocol:2013/10/3. [18] Thompson, R.L., Higgins, C.A., and Howell, J.M.(1991), “Personal Computing: Toward a Conceptual Model of Utilization”, MIS Quarterly(15:1), pp. 125-143. [19] Venkatesh, V., M.G. Morris, G.B. Davis, and F. D. Davis (2003), “User acceptance of information technology: Toward a unified view, ” MIS Quarterly, 27, No. 3, pp.425-478. [20] Vijayasarathy, L. R. (2004), Predicting Consumer Intentions to Use On-Line Shopping： The Case for an Augmented Technology Acceptance Model, Information and Management, Vol.41, No.6, pp.747-762. [21] Wikipedia - smartphone (http://zh.wikipedia.org/zh-tw/%E6%99%BA%E8%83%BD%E6%89%8B%E6%9C%BA)。 [22] Wu-Minsan (2008).The impacts of self-efficacy, social support on work adjustment with hearing impaired. (Master's dissertation, Southern Taiwan University of Science and Technology, 2008).National Digital Library of Theses and Dissertations in Taiwan. [23] Yu-min Lin (2006). The Influence of Business Employee’s MSN Self-efficacy On Instant Messaging Usage Behavior and Communicaiton Satisfaction.(Master's dissertation, National Taiwan University of Science and Technology, 2006).National Digital Library of Theses and Dissertations in Taiwan.

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Authors: Maria R. A. R. Moreira, Francisco R. O. Da Silva, André O. A. Fontenele, Érick A. Ribeiro

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This article deals with the influence of technology in education showing educational robotics as pedagogical method of solution for knowledge building. We are proposing the development and implementation of four robot models that can be used for teaching purposes involving the areas of mechatronics, mechanics, electronics and computing, making it efficient for learning other sciences and theories. One of the main reasons for application of the developed educational kits is its low cost, allowing its applicability to a greater number of educational institutions. The technology will add to education dissemination of knowledge by means of experiments in such a way that the pedagogical robotics promotes understanding, practice, solution and criticism about classroom challenges. We also present the relationship between education, science, technology and society through educational robotics, treated as an incentive to technological careers.

Keywords: education, mecatronics, robotics, technology

Procedia PDF Downloads 389

Authors: Reda A. Elkhyat, Mahmoud Nasr, Amel A. Tammam, Mohamed A. Ghazy

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Pharmaceuticals and personal care products (PPCPs) are a unique group of emerging contaminants continuously introduced into the aquatic ecosystem at concentrations capable of inducing adverse effects on humans and aquatic organisms, even at trace levels ranging from ppt to ppm. Amongst the common pharmaceutical emerging pollutants detected in several aquatic environments, acetaminophen has been recognized for its high toxicity. Once released into the aquatic environment, acetaminophen could be degraded by the microbial community and adsorption/ uptake by the plants. Although many studies have investigated the hazard risks of acetaminophen pollutants on aquatic animals, the number of studies demonstrating its removal efficiency and effects on the aquatic plant still needs to be expanded. In this context, this study aims to apply the aquatic plant-based phytoremediation system to eliminate this emerging contaminant from domestic wastewater. The phytoremediation experiment was performed in a hydroponic system containing Eichhornia crassipes and operated under the natural environment at 25°C to 30°C. This system was subjected to synthetic domestic wastewater with the maximum initial chemical oxygen demand (COD) of 390 mg/L and three different acetaminophen concentrations of 25, 50, and 200 mg/L. After 17 d of operation, the phytoremediation system achieved removal efficiencies of about 100% and 85.6±4.2% for acetaminophen and COD, respectively.Moreover, the Eichhornia crassipes could withstand the toxicity associated with increasing the acetaminophen concentrations from 25 to 200 mg/L. This high treatment performance could be assigned to the well-adaptation of the water hyacinth to the phytoremediation factors. Moreover, it has been proposed that this phytoremediation system could be largely supported by phytodegradation and plant uptaking mechanisms; however, detecting the generated intermediates, metabolites, and degradation products are still under investigation. Applying this free-floating plant in wastewater treatment and reducing emerging contaminants would meet the targets of SDGs 3, 6, and. 14. The cost-benefit analysis was performed for the phytoremediation system. The phytoremediation system is financially viable as the net profit was 2921 US $/ y with a payback period of nine years.

Keywords: domestic wastewater, emerging pollutants, hydrophyte Eichhornia crassipes, paracetamol removal efficiency, sustainable development goals (SDGs)

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Authors: Ma. Cecilia D. Licuan

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The pandemic situation continues to affect the lives of many people, including children with disabilities and their families, globally, especially in developing countries like the Philippines. The operations of health programs, industries, and economic sectors, as well as academic training institutions, are still challenged in terms of operations and delivery of services. The academic community of the Physical Therapy program is not spared by this circumstance. The restriction posted by the quarantine policies nearly terminated the onsite delivery of training programs for the senior internship level, which challenged the academic institutions to implement flexible learning programs to ensure the continuity of the instructional and learning processes with full consideration of safety and compliance to health protocols. This study aimed to develop a benchmark model that can be used by tertiary-level health institutions in the implementation of the Pediatric Senior Clinical Internship Training Program using Telerehabilitation. It is a descriptive-qualitative paper that utilized documentary analysis and focused on explaining the design, development, and implementation processes used by De La Salle Medical and Health Sciences Institute – College of Rehabilitation Sciences (DLSMHSI-CRS) Physical Therapy Department in its Pediatric Cluster Senior Clinical Internship Training Program covering the pandemic years spanning from the academic year 2020- 2021 to present anchored on needs analysis based on documentary reviews. Results of the study yielded the determination of the Pediatric Telerehabilitation Model; declaration of developed training program outcomes and thrusts and content; explanation of the process integral to the training program’s pedagogy in implementation; and the evaluation procedures conducted for the program. Since the study did not involve human participants, ethical considerations on the use of documents for review were done upon the endorsement of the management of the DLSMHSI-CRS to conduct the study. This paper presents the big picture of how a tertiary-level health sciences institution in the Philippines embraced the senior clinical internship challenges through the operations of its telerehabilitation program. It specifically presents the design, development and implementation processes used by De La Salle Medical and Health Sciences Institute – College of Rehabilitation Sciences Physical Therapy Department in its Pediatric Cluster Senior Clinical Internship Training Program, which can serve as a benchmark model for other institutions as they continue to serve their stakeholders amidst the pandemic.

Keywords: pediatric physical therapy, telerehabilitation, clinical internship, pandemic

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Authors: Mark Ivan Roblas

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The Science Explorer is a mobile learning science facility in the Philippines. It is a bus that travels to different provinces in the country bringing interactive science modules facilitated by scientists from the industry and academe. The project aims to entice students to get into careers in science through interactive science modules and interaction with real-life scientists. This article looks into the effectiveness of its modules as a communication source and message to encourage high school students to get into careers in the future. The study revealed that as the Science Explorer modules are able to retain students to stay in science careers of their choice and even convert some to choose from non-science to a science degree, it still lacks in penetrating the belief system of the students and influencing them to take a scientific career path.

Keywords: informal science, mobile science, science careers, science education

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Authors: Jonghyuk Yoon, Jongil Yoon, Seong-Gyo Chung

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In many kinds of industries which usually need a large amount of power, an axial piston pump has been widely used as a main power source of a hydraulic system. The axial piston pump is a type of positive displacement pump that has several pistons in a circular array within a cylinder block. As the cylinder block and pistons start to rotate, since the exposed ends of the pistons are constrained to follow the surface of the swashed plate, the pistons are driven to reciprocate axially and then a hydraulic power is produced. In the present study, a numerical simulation which has three dimensional full model of the axial piston pump was carried out using a commercial CFD code (Ansys CFX 14.5). In order to take into consideration motion of compression and extension by the reciprocating pistons, the moving boundary conditions were applied as a function of the rotation angle to that region. In addition, this pump using hydraulic oil as working fluid is intentionally designed as a small amount of oil leaks out in order to lubricate moving parts. Since leakage could directly affect the pump efficiency, evaluation of effect of oil-leakage is very important. In order to predict the effect of the oil leakage on the pump efficiency, we considered the leakage between piston-shoe and swash-plate by modeling cylindrical shaped-feature at the end of the cylinder. In order to validate the numerical method used in this study, the numerical results of the flow rate at the discharge port are compared with the experimental data, and good agreement between them was shown. Using the validated numerical method, the effect of the discharge pressure was also investigated. The result of the present study can be useful information of small axial piston pump used in many different manufacturing industries. Acknowledgement: This research was financially supported by the “Next-generation construction machinery component specialization complex development program” through the Ministry of Trade, Industry and Energy (MOTIE) and Korea Institute for Advancement of Technology (KIAT).

Keywords: axial piston pump, CFD, discharge pressure, hydraulic system, moving boundary condition, oil leaks

Procedia PDF Downloads 251