Search results for: mutliloop fractional order PID controller

Authors: Eun-Ji Lee, Hye-Sung Park, Chan-Jung Lee, Won-Sik Kong

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We analyzed the DNA sequence of the ITS (Internal Transcribed Spacer) region of the 18S ribosomal gene and compared it with the gene sequence of T. fuciformis and Hypoxylon sp. in the BLAST database. The sequences of collected T. fuciformis and Hypoxylon sp. have over 99% homology in the T. fuciformis and Hypoxylon sp. sequence BLAST database. In order to select the optimal medium for T. fuciformis, five kinds of a medium such as Potato Dextrose Agar (PDA), Mushroom Complete Medium (MCM), Malt Extract Agar (MEA), Yeast extract (YM), and Compost Extract Dextrose Agar (CDA) were used. T. fuciformis showed the best growth on PDA medium, and Hypoxylon sp. showed the best growth on MCM. So as to investigate the optimum pH and temperature, the pH range was set to pH4 to pH8 and the temperature range was set to 15℃ to 35℃ (5℃ degree intervals). Optimum culture conditions for the T. fuciformis growth were pH5 at 25℃. Hypoxylon sp. were pH6 at 25°C. In order to confirm the most suitable carbon source, we used fructose, galactose, saccharose, soluble starch, inositol, glycerol, xylose, dextrose, lactose, dextrin, Na-CMC, adonitol. Mannitol, mannose, maltose, raffinose, cellobiose, ethanol, salicine, glucose, arabinose. In the optimum carbon source, T. fuciformis is xylose and Hypoxylon sp. is arabinose. Using the column test, we confirmed sawdust a suitable for T. fuciformis, since the composition of sawdust affects the growth of fruiting bodies of T. fuciformis. The sawdust we used is oak tree, pine tree, poplar, birch, cottonseed meal, cottonseed hull. In artificial cultivation of T. fuciformis with sawdust medium, T. fuciformis and Hypoxylon sp. showed fast mycelial growth on mixture of oak tree sawdust, cottonseed hull, and wheat bran.

Keywords: cultivation, optimal condition, tremella fuciformis, nutritional source

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Authors: Priyanwada I. Singhapathirana

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The public land ownership is a common phenomenon in many countries in the world however, the development approaches and the institutional structures are greatly diverse. The existing scholarship around public land development has been greatly limited to Europe and advanced Asian economies. Inferences of such studies seem to be inadequate and inappropriate to comprehend the peculiarities of public land development in developing Asian economies. The absence of critical inquiry on the public land ownership and the long-established institutional structures which govern the development has restrained these countries from institutional innovations. In this context, this research investigates the issues related to public land development and the institutional responses in Sri Lanka. This study introduces the concept of ‘Institutional Responsiveness’ in Public land development, which is conceptualized as the ability of the institutions to respond to the spatial, market and fiscal stimulus. The inquiry was carried out through in-depth interviews with five key informants from apex public agencies in order to explore the responsiveness of land institutions form decision-makers' perspectives. Further, the analysis of grey literature and recent media reports are used to supplement the analysis. As per the findings, long term abandonment of public lands and high transaction costs are some of the key issues in relation to public land development. The inability of the institutions to respond to the market and fiscal stimulus has left many potential public lands underutilized. As a result, the public sector itself and urban citizens have not been able to relish the benefits of the public lands in cities. Spatial analysis at the local scale is suggested for future studies in order to capture the multiple dimensions of the responsiveness of institutions to the development stimulus.

Keywords: institutions, public land, responsiveness, under-utilization

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Authors: Piotr Kunecki, Magdalena Wdowin

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The fly ash produced as waste in the process of conventional coal combustion was utilized in the hybrid synthesis of zeolites X and A from Faujasite (FAU) and Linde Type A (LTA) frameworks, respectively. The applied synthesis method included modification together with the crystallization stage. The sorbent modification was performed by introducing metals into the zeolite structure in order to create an ability to form stable bonds with elemental mercury (Hg0). The use of waste in the form of fly ash as a source of silicon and aluminum, as well as the proposed method of zeolite synthesis, fits the circular economy idea. The effect of zeolite modification on Hg0 removal from a simulated gas stream was studied empirically using prototype installation designed to test the effectiveness of sorption by solid-state sorbents. Both derived zeolites X and A modified with silver nitrate revealed significant mercury uptake during a 150-minute sorption experiment. The amount of elemental mercury removed in the experiment ranged from 5.69 to 6.01 µg Hg0/1g of sorbent for zeolites X and from 4.47 to 4.86 µg Hg0/1g of sorbent for zeolites A. In order to confirm the effectiveness of the sorbents towards mercury bonding, the possible re-emission effect was tested as well. Derived zeolites X and A did not show mercury re-emission after the sorption process, which confirms the stable bonding of Hg0 in the structure of synthesized zeolites. The proposed hybrid synthesis method possesses the potential to be implemented for both fly ash utilization as well as the time and energy-saving production of aluminosilicate, porous materials with high Hg0 removal efficiency. This research was supported by National Science Centre, Poland, grant no 2021/41/N/ST5/03214.

Keywords: fly ash, synthetic zeolites, elemental mercury removal, sorption, simulated gas stream

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Authors: Rachel K. Cremona

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Forty years ago, Vila Autodromo was a small fishing settlement in southwest Rio de Janeiro. By 2012, Vila Autodromo had established itself into a working class neighborhood – certainly not a slum, but nonetheless designated as a ‘favela’ as a consequence of its history as an illegal settlement that was thus never provided with public services. Vila Autodromo sits on a large lagoon, adjacent to the Olympic Park being constructed for the 2016 Olympic Games to be held in Rio, and looks out over the expensive high rise condominiums that have sprouted across the water. In 2009, when Rio submitted their bid for the Olympic games, there were approximately 900 families that called Vila Autodromo home, and the original plans for the games clearly show their homes remaining in place. Today, only a handful of these homes remain. This paper will utilize the case study of Vila Autodromo to examine the broader issue of Favelas in 21st century Rio de Janeiro. While race and poverty have become synonymous with Brazil’s inegalitarian social order – and personified by the thousands of favelas scattered in and around large cities like Rio and Sao Paulo – much less attention has been given to the political status of the nation’s invisible majority. In particular, this research will examine the question of citizenship and argue that the most fundamental problem of inequality in Brazil is not simply a product of history, race and social order, but more specifically a problem of ‘personhood’. The political marginalization of Brazil’s poor does not simply reinforce their social marginalization, it institutionalizes it in a way that makes it almost impossible to escape. The story of Vila Autodromo captures this problem in a way that not only illustrates the clear (though ambiguous) role of the state in the perpetuation of Brazil’s underclass, but also the human resilience that it has fostered.

Keywords: citizenship, poverty, displacement, favela

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Authors: Ana Julia C. Kfouri

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A prerequisite of any building design is to provide security to the users, taking the climate and its physical and physical-geometrical variables into account. It is also important to highlight the relevance of the right material elements, which arise between the person and the agent, and must provide improved thermal comfort conditions and low environmental impact. Furthermore, technology is constantly advancing, as well as computational simulations for projects, and they should be used to develop sustainable building and to provide higher quality of life for its users. In relation to comfort, the more satisfied the building users are, the better their intellectual performance will be. Based on that, the study of thermal comfort in educational buildings is of relative relevance, since the thermal characteristics in these environments are of vital importance to all users. Moreover, educational buildings are large constructions and when they are poorly planned and executed they have negative impacts to the surrounding environment, as well as to the user satisfaction, throughout its whole life cycle. In this line of thought, to evaluate university classroom conditions, it was accomplished a detailed case study on the thermal comfort situation at Federal University of Parana (UFPR). The main goal of the study is to perform a thermal analysis in three classrooms at UFPR, in order to address the subjective and physical variables that influence thermal comfort inside the classroom. For the assessment of the subjective components, a questionnaire was applied in order to evaluate the reference for the local thermal conditions. Regarding the physical variables, it was carried out on-site measurements, which consist of performing measurements of air temperature and air humidity, both inside and outside the building, as well as meteorological variables, such as wind speed and direction, solar radiation and rainfall, collected from a weather station. Then, a computer simulation based on results from the EnergyPlus software to reproduce air temperature and air humidity values of the three classrooms studied was conducted. The EnergyPlus outputs were analyzed and compared with the on-site measurement results to be possible to come out with a conclusion related to the local thermal conditions. The methodological approach included in the study allowed a distinct perspective in an educational building to better understand the classroom thermal performance, as well as the reason of such behavior. Finally, the study induces a reflection about the importance of thermal comfort for educational buildings and propose thermal alternatives for future projects, as well as a discussion about the significant impact of using computer simulation on engineering solutions, in order to improve the thermal performance of UFPR’s buildings.

Keywords: computer simulation, educational buildings, EnergyPlus, humidity, temperature, thermal comfort

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Authors: I. Nitoi, P. Oancea, M. Raileanu, M. Crisan, L. Constantin, I. Cristea

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Hazardous organic compounds like nitroaromatics are frequently found in chemical and petroleum industries discharged effluents. Due to their bio-refractory character and high chemical stability cannot be efficiently removed by classical biological or physical-chemical treatment processes. In the past decades, semiconductor photocatalysis has been frequently applied for the advanced degradation of toxic pollutants. Among various semiconductors titania was a widely studied photocatalyst, due to its chemical inertness, low cost, photostability and nontoxicity. In order to improve optical absorption and photocatalytic activity of TiO2 many attempts have been made, one feasible approach consists of doping oxide semiconductor with metal. The degradation of dinitrobenzene (DNB) and dinitrotoluene (DNT) from aqueous solution under UVA-VIS irradiation using heavy metal (0.5% Fe, 1%Co, 1%Ni ) doped titania was investigated. The photodegradation experiments were carried out using a Heraeus laboratory scale UV-VIS reactor equipped with a medium-pressure mercury lamp which emits in the range: 320-500 nm. Solutions with (0.34-3.14) x 10-4 M pollutant content were photo-oxidized in the following working conditions: pH = 5-9; photocatalyst dose = 200 mg/L; irradiation time = 30 – 240 minutes. Prior to irradiation, the photocatalyst powder was added to the samples, and solutions were bubbled with air (50 L/hour), in the dark, for 30 min. Dopant type, pH, structure and initial pollutant concentration influence on the degradation efficiency were evaluated in order to set up the optimal working conditions which assure substrate advanced degradation. The kinetics of nitroaromatics degradation and organic nitrogen mineralization was assessed and pseudo-first order rate constants were calculated. Fe doped photocatalyst with lowest metal content (0.5 wt.%) showed a considerable better behaviour in respect to pollutant degradation than Co and Ni (1wt.%) doped titania catalysts. For the same working conditions, degradation efficiency was higher for DNT than DNB in accordance with their calculated adsobance constants (Kad), taking into account that degradation process occurs on catalyst surface following a Langmuir-Hinshalwood model. The presence of methyl group in the structure of DNT allows its degradation by oxidative and reductive pathways, while DNB is converted only by reductive route, which also explain the highest DNT degradation efficiency. For highest pollutant concentration tested (3 x 10-4 M), optimum working conditions (0.5 wt.% Fe doped –TiO2 loading of 200 mg/L, pH=7 and 240 min. irradiation time) assures advanced nitroaromatics degradation (ηDNB=89%, ηDNT=94%) and organic nitrogen mineralization (ηDNB=44%, ηDNT=47%).

Keywords: hazardous organic compounds, irradiation, nitroaromatics, photocatalysis

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Authors: Sarada Prasad Pradhan, Vikram Vishal, Tariq Siddique

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With a vast area of India comprising of hilly terrain and road cut slopes, landslides and rockfalls are a common phenomenon. However, while landslide studies have received much attention in the past in India, very little literature and analysis is available regarding rockfall hazard of many rockfall prone areas, specifically in Uttarakhand Himalaya, India. The subsequent lack of knowledge and understanding of the rockfall phenomenon as well as frequent incidences of rockfall led fatalities urge the necessity of conducting site-specific rockfall studies to highlight the importance of addressing this issue as well as to provide data for safe design of preventive structures. The present study has been conducted across 10 rockfall prone road cut slopes for a distance of 15 km starting from Devprayag, India along National Highway 58 (NH-58). In order to make a qualitative assessment of Rockfall Hazard posed by these slopes, Rockfall Hazard Rating using standards for Indian Rockmass has been conducted at 10 locations under different slope conditions. Moreover, to accurately predict the characteristics of the possible rockfall phenomenon, numerical simulation was carried out to calculate the maximum bounce heights, total kinetic energies, translational velocities and trajectories of the falling rockmass blocks when simulated on each of these slopes according to real-life conditions. As it was observed that varying slope geometry had more fatal impacts on Rockfall hazard than size of rock masses, several optimizations have been suggested for each slope regarding location of barriers and modification of slope geometries in order to minimize damage by falling rocks. This study can be extremely useful in emphasizing the significance of rockfall studies and construction of mitigative barriers and structures along NH-58 around Devprayag.

Keywords: rockfall, slope stability, rockmass, hazard

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Authors: Mohammad Saif

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In the post-Westphalianworld order, the concept of sovereignty has been a fundamental area of inquiry in Political Science, International Relations, and International Law. Modern Islamic political thought has also dedicated a fair share of debate on the subject. The debate fundamentally revolves around the ‘ontological differentiation’ between western and Islamic political thought. While the centrality of the individual in western political thought regards the individual as the center of universe, Islamic Political thought provides that space to God. The modern liberal democratic principles suggest sovereignty as one of the major attributes of modern nation state; Islamists regard sovereignty as an attribute of God. However, the position regarding God’ssovereignty in Islamic political thought is not coherent in conception. Some scholars regard such a position as ‘the political interpretation of Islam’. This paper is an attempt to first analyze the fundamental discord between two rival political ideologies (western and Islamic), and then forward a debate on the subject of sovereignty in South Asian Islamic Political thought, particularly between Syed Abul Ala Maududi (ideological father of modern islamist movements) andHifzurrahmanSeoharvi (lesser known in Academia but highly influential in shaping Deobandi position of principles related to political nature of Islamic theology). Maududi regardssovereignty as an attribute of God and the rulers as subservient to Gods will, Seoharvi suggests that God's sovereignty does not entail that the caliph or amir cannot be a ruler or hakim, nor can his command or hukum be an order. Certain references have also been made to contemporary scholars like Sayidd Qutub, Rashid al Ghanouchi, who in one way or the other have contributed to the debate on ‘sovereignty in Islamic thought’.

Keywords: nation state, sovereigty, sovereignty of God (Hakimmiyah), deoband

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Authors: S. M. Amin Hosseini, Oriol Pons, Albert de la Fuente

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An earthquake hit the Kermanshah province, which is located in the west of Iran, on 12th November 2017 at 18:18 UTC (21:48 Iran Standard Time). This earthquake caused several deaths and injured people. In this disaster, substantial homes were destroyed and many homes were damaged. The Iranian government, local authorities, and several non-governmental organizations responded to affected populations’ needs, such as foods, blanket, water, a tent as a temporary shelter, etc. Considerable national groups, including governmental, non-governmental organizations, and people from non-organized groups, directly and indirectly, tried to bring donated goods to the affected populations. However, some of these aids could not satisfy all the affected populations. Moreover, these impossibilities led to waste extensive resources. In this regard, this research study aims to assess the problems of the Kermanshah disaster responses. At the same time, this project searches possible solutions in order to increase emergency management efficiencies for encountering future events. To this end, this study assesses the problem from all beneficiaries´ point of views. In this regard, a survey and a questionnaire were designed for statistical analyses of the responses of people, who were involved in the Kermanshah earthquake recovery program. Additionally, this research study takes into account diverse strategies, which have been applied in other recovery programs, with the Kermanshah case in order to determine similarities and differences. Finally, this study presents possible solutions taken from other recovery programs that could be applied for the Kermanshah emergency responses. However, the results demonstrate that it is required to customize applied strategies based on local conditions and requirements.

Keywords: disaster response, Kermanshah earthquake, natural disasters, NGOs

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Authors: Usharani Rathinam

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Although policies directing inclusion of marginalized were in effect, majority of chronically impoverished in India belonged to schedule caste and schedule tribes. Also, taking into account that poverty is gendered; destitute women belonged to lower social order whose need is not largely highlighted at policy level. This paper discusses on social relations poverty which highlights on how social order that existed structurally in the society can perpetuate chronic poverty, followed by a critical review on social inclusion policies of India, its merits and demerits in addressing chronic poverty. Multiple case study design is utilized to address this concern in four districts of India; Jhansi, Tikamgarh, Cuddalore and Anantapur. These four districts were selected by purposive sampling based on the criteria; the district should either be categorized as a backward district or should have a history of high poverty rate. Qualitative methods including eighty in-depth interviews, six focus group discussions, six social mapping procedures and three key informant interviews were conducted in 2011, at each of the locations. Analysis of the data revealed that irrespective of gender, schedule castes and schedule tribe participants were found to be chronically poor in all districts. Caste based discrimination is exhibited at both micro and macro levels; village and institutional levels. At village level, lower caste respondents had lesser access to public resources. Also, within institutional settings, due to confiscation, unequal access to resources is noticed, especially in fund distribution. This study found that half of the budget intended for schedule caste and schedule tribes were confiscated by upper caste administrative staffs. This implies that power based on social hierarchy marginalize lower caste participants from accessing better economic, social, and political benefits, that had led them to suffer long term poverty. This study also explored the traditional ties between caste, social structure and bonded labour as a cause of long-term poverty. Though equal access is being emphasized in constitutional rights, issues at micro level have not been reflected in formulation of these rights. Therefore, it is significant for a policy to consider the structural complexity and then focus on issues such as equal distribution of assets and infrastructural facilities that will reduce exclusion and foster long-term security in areas such as employment, markets and public distribution.

Keywords: caste, inclusion policies, India, social order

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Authors: H. E. M. W. G. M. K. Ekanayake, J. Dharmasena

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Natural Landscape fragmentation and habitat loss are emerging issues in Sri Lanka, which is due to rapid urban development and inadequate concern of managing Landscape connectivity. Urban Wetlands are the most vulnerable ecosystem effects from the fragmentation. Therefore, management of landscape connectivity with proper analysis and understanding has become a most important measure for urban wetland habitats. This study aimed to introduce spatial planning strategy to identify and locate landscape developments appropriately in order to restore landscape connectivity. Therefore, the study focuses on understanding the relationship between habitat patch metrics and landscape connectivity with reference to Colombo wetlands. Geographic Information Systems (GIS) was used to measure the wetland patch metrics; Patch area, Total edge, Perimeter-area ratio, Core area index and Inter-patch distances. Further, GIS-enabled least-cost path tool was used to measure the Landscape connectivity and calculate the number of species flow paths per wetland patch. According to the research findings; increasing the patch area, maintaining a mean perimeter-area ratio and core area index also reducing the inter-patch distances could enhance the landscape connectivity. Further, this study introduces three patch typologies; ‘active patches,' ‘open patches’ and ‘closed patches’ that severs to landscape connectivity in different levels. In the end, the study proposes a strategy for Landscape Architects to select most suitable locations to implement ecological based landscape developments with adjacent to the existing urban habitat in order to enhance habitat patch metrics and to restore the landscape connectivity.

Keywords: landscape fragmentation, urban wetlands, landscape connectivity, patch metrics

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Authors: Chrysovalanto Sofia Karatosidi, Dimitra Iordanoglou

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The overlap of leadership skills with personality traits, beliefs, values, and the integration of cognitive abilities, analytical and critical thinking skills into leadership competencies raises the need to segregate further and investigate them. Hence, the domains of cognitive functions that contribute to leadership effectiveness should also be identified. Organizational cognitive neuroscience and neuroleadership can shed light on the study of these critical leadership skills. As the first part of our research, this pilot study aims to explore the relationships between higher-order cognitive functions (executive functions), trait emotional intelligence (EI), personality, and general cognitive ability in leadership. Twenty-six graduate and postgraduate students were assessed on neuropsychological tests that measure important aspects of executive functions (EF) and completed self-reported questionnaires about trait EI, personality, leadership styles, and leadership effectiveness. Specifically, we examined four core EF—fluency (phonemic and semantic), information updating and monitoring, working memory, and inhibition of prepotent responses. Leadership effectiveness was positively associated with phonemic fluency (PF), which involves mental flexibility, in turn, an increasingly important ability for future leaders in this rapidly changing world. Transformational leadership was positively associated with trait EI, extraversion, and openness to experience, a result that is following previous findings. The relationship between specific EF constructs and leadership effectiveness emphasizes the role of higher-order cognitive functions in the field of leadership as an individual difference. EF brings a new perspective into leadership literature by providing a direct, non-invasive, scientifically-valid connection between brain function and leadership behavior.

Keywords: cognitive neuroscience, emotional intelligence, executive functions, leadership

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Authors: Yangwon Hyun

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Nowadays, business settings are becoming increasingly multilingual and multicultural under the conditions of globalization. When people from different linguistic and cultural background interact, their divergent cultural conceptualizations may result in communicative problems. Even though intercultural business communication between Thais and South Koreans has become increasingly significant along with the development of international trade relations, there have been very few attempts to conduct research on interactional problems in that context. Based on a Cultural Linguistics perspective, this study analyzes Thai cultural conceptualizations that underly interactional problems with Koreans at Korean business organizations where were located in Thailand. The data was gathered through in-depth interviews with ten Korean and ten Thai employees as well as through six months of field observations. The results indicate that there are three cultural pragmatic schemas that underly problems of interaction between the two groups; (1) the schema of kreng-jai as a communicative strategy of withholding one’s intentions in order to not hurt another’s emotion, (2) the schema of mai-pen-rai as a linguistic strategy of inducing interlocutors to not be concerned about substantial matters so as to avoid confrontations, and (3) the schema of jai-yen as a linguistic expression used for persuading interlocutors to maintain a calm state of mind in order to avoid conflicts. The linguistic behaviors of Thai employees in relation to these three cultural schemas had led to misunderstandings and interpersonal conflicts with Korean supervisors and co-workers. These interactional problems were caused not only because Koreans were unfamiliar with Thai cultural conceptualizations, but also because these conceptualizations were incompatible with goal-oriented Korean business discourse. The findings of this study can enhance mutual understandings between Thai and Korean employees. Thus, it contributes to the promotion of smooth intercultural communication in the workplace.

Keywords: business context, cultural conceptualizations, cultural linguistics, intercultural communication, thai culture

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Authors: Daniel Zarzo Montes, Manuel Zarzo Castelló

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Proteins play a fundamental role in biology, but their structure is complex, and it is a challenge for teachers to conceptually explain the differences between their primary, secondary, tertiary, and quaternary structures. On the other hand, there are currently many computer programs to visualize the 3D structure of proteins, but they require advanced training and knowledge. Moreover, it becomes difficult to visualize the sequence of amino acids in these models, and how the protein conformation is reached. Given this drawback, a simple and instructive procedure is proposed in order to teach the protein structure to undergraduate and graduate students. For this purpose, insulin has been chosen because it is a protein that consists of 51 amino acids, a relatively small number. The methodology has consisted of the use of plastic atom models, which are frequently used in organic chemistry and biochemistry to explain the chirality of biomolecules. For didactic purposes, when the aim is to teach the biochemical foundations of proteins, a manipulative system seems convenient, starting from the chemical structure of amino acids. It has the advantage that the bonds between amino acids can be conveniently rotated, following the pattern marked by the 3D models. First, the 51 amino acids were modeled, and then they were linked according to the sequence of this protein. Next, the three disulfide bonds that characterize the stability of insulin have been established, and then the alpha-helix structure has been formed. In order to reach the tertiary 3D conformation of this protein, different interactive models available on the Internet have been visualized. In conclusion, the proposed methodology seems very suitable for biology and biochemistry students because they can learn the fundamentals of protein modeling by means of a manipulative procedure as a basis for understanding the functionality of proteins. This methodology would be conveniently useful for a biology or biochemistry laboratory practice, either at the pre-graduate or university level.

Keywords: protein structure, 3D model, insulin, biomolecule

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Authors: Omar Concepcion, Osvaldo De Melo, Arturo Escobosa

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Topological insulator (TI) materials are insulating in the bulk and conducting in the surface. The unique electronic properties associated with these surface states make them strong candidates for exploring innovative quantum phenomena and as practical applications for quantum computing, spintronic and nanodevices. Many materials, including Bi₂Te₃, have been proposed as TIs and, in some cases, it has been demonstrated experimentally by angle-resolved photoemission spectroscopy (ARPES), scanning tunneling spectroscopy (STM) and/or magnetotransport measurements. A clean surface is necessary in order to make any of this measurements. Several techniques have been used to produce films and different kinds of nanostructures. Growth and characterization in situ is usually the best option although cleaving the films can be an alternative to have a suitable surface. In the present work, we report a comparison of Bi₂Te₃ grown by physical vapor transport (PVT) and molecular beam epitaxy (MBE). The samples were characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM), Atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and ARPES. The Bi₂Te₃ samples grown by PVT, were cleaved in the ultra-high vacuum in order to obtain a surface free of contaminants. In both cases, the XRD shows a c-axis orientation and the pole diagrams proved the epitaxial relationship between film and substrate. The ARPES image shows the linear dispersion characteristic of the surface states of the TI materials. The samples grown by PVT, a relatively simple and cost-effective technique shows the same high quality and TI properties than the grown by MBE.

Keywords: Bismuth telluride, molecular beam epitaxy, physical vapor transport, topological insulator

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Authors: Chiyoung Kim, Jaegeol Yim

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Bus service is often either main or the only public transportation available in cities. In metropolitan areas, both subways and buses are available whereas in the medium sized cities buses are usually the only type of public transportation available. Bus Information Systems (BIS) provide current locations of running buses, efficient routes to travel from one place to another, points of interests around a given bus stop, a series of bus stops consisting of a given bus route, and so on to users. Thanks to BIS, people do not have to waste time at a bus stop waiting for a bus because BIS provides exact information on bus arrival times at a given bus stop. Therefore, BIS does a lot to promote the use of buses contributing to pollution reduction and saving natural resources. BIS implementation costs a huge amount of budget as it requires a lot of special equipment such as road side equipment, automatic vehicle identification and location systems, trunked radio systems, and so on. Consequently, medium and small sized cities with a low budget cannot afford to install BIS even though people in these cities need BIS service more desperately than people in metropolitan areas. It is possible to provide BIS service at virtually no cost under the assumption that everybody carries a smartphone and there is at least one person with a smartphone in a running bus who is willing to reveal his/her location details while he/she is sitting in a bus. This assumption is usually true in the real world. The smartphone penetration rate is greater than 100% in the developed countries and there is no reason for a bus driver to refuse to reveal his/her location details while driving. We have developed a mobile app that periodically reads values of sensors including GPS and sends GPS data to the server when the bus stops or when the elapsed time from the last send attempt is greater than a threshold. This app detects the bus stop state by investigating the sensor values. The server that receives GPS data from this app has also been developed. Under the assumption that the current locations of all running buses collected by the mobile app are recorded in a database, we have also developed a web site that provides all kinds of information that most BISs provide to users through the Internet. The development environment is: OS: Windows 7 64bit, IDE: Eclipse Luna 4.4.1, Spring IDE 3.7.0, Database: MySQL 5.1.7, Web Server: Apache Tomcat 7.0, Programming Language: Java 1.7.0_79. Given a start and a destination bus stop, it finds a shortest path from the start to the destination using the Dijkstra algorithm. Then, it finds a convenient route considering number of transits. For the user interface, we use the Google map. Template classes that are used by the Controller, DAO, Service and Utils classes include BUS, BusStop, BusListInfo, BusStopOrder, RouteResult, WalkingDist, Location, and so on. We are now integrating the mobile app system and the web app system.

Keywords: bus information system, GPS, mobile app, web site

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Authors: Sila K. Sari, Betty J.L. Laglbauer, Muhammad G. Salim, Irianies C. Gozali, Iqbal Herwata, Fahmi Fahmi, Selvia Oktaviyani, Isabel Ender, Sarah Lewis, Abraham Sianipar, Mark Erdmann

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Taking strides towards the sustainable use of marine stocks requires science-based management of target fish populations and reduction of bycatch in non-selective fisheries. Among elasmobranchs, mobulid rays are faced with high extinction risk due to intrinsic vulnerability to fishing and their conservation has been recognized as a strong priority both in Indonesia and worldwide. Despite their common vulnerabilities to fishing pressure due to slow growth, late maturation and low fecundity, only manta rays, but not devil rays, are protected in Indonesian waters. However, both manta and devil rays are captured in non-selective fisheries, in particular drift gillnets, since their habitat overlaps with fishing grounds for primary target species (e.g. marlin, swordfish and bullet tuna off the coast of Muncar). For this reason, mobulid populations are being heavily impacted, and while national-level protections are crucial to help conservation, they may not suffice alone to insure populations sustainability. In order to assess the potential of applying live-release management measures to conserve mobulids captured as bycatch in drift gillnets, we deployed pop-up survival archival transmitters to assess post-release mortality in Indonesian mobulid rays. We also assessed which fishing practices, in particular, soak duration, affected post-release mortality in order to draw relevant conclusions for management.

Keywords: Mobulid, Devil ray, Manta ray, Bycatch

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Authors: A. Llopis Alvarez, D. Muller-Eie

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Participatory GIS (geographic information systems) are designed for community mapping exercises in order to produce spatial representations of local knowledge. Ideally, participatory GIS caters to public participation through the use of spatial data in order to increase community-led policy-and decision-making. Having defined a spatial object, such as a neighborhood, subjective mapping involves attaining a description of the spatial, physical, social and psychological characteristics of that spatial object. This paper highlights an emerging appreciation of the subjective component, particularly in spatial analyses. The beliefs, feelings, and behaviors associated with an urban area reflect its sense of place for an individual or a group. It is important therefore to understand what types of beliefs, emotions, and behavioral patterns are relevant to particular resident, groups and urban scales. In this sense, resident’s emotional attachment to their urban areas motivates civic engagement and facilitates awareness of its strengths and its problems. Similarly, subjective perceptions act in complex ways to influence the formation and maintenance of social identity and quality of life. This paper reports on findings from a case study of immigrant population in Norwegian cities, their residential conditions and their relationship to quality of urban life. Cognitive mapping methodologies are used in this study to understand local perceptions of urban qualities. Thus, measures to alleviate disadvantages and improve quality of urban life are more likely to be effective when they are informed by an understanding of a place as constructed by those who live in it, meaning their subjective perceptions about it.

Keywords: mapping methodologies, participatory GIS, perceptual maps, public participation, spatial analysis, subjective perceptions

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Authors: Papitchaya Papangkorn

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Matching the expectations of teachers and learners is significant for successful language learning. Moreover, teachers should discover what their learners think and feel about what and how they want to learn. Therefore, this study investigates International College, Suan Sunandha Rajabhat University students’ preferences toward error corrections in order to help SSRUIC teachers match their expectations and their learners because it is important for successful language learning. This study examined the learners’ attitude and preference toward error correction through 50 first year SSRUIC students both male (25) and female (25) in Bangkok, Thailand. The data were collected from a questionnaire and interviews to investigate the necessity and frequency, timing, type of errors, method of corrective feedback, and person who gives error correction in order to answer the overall research question and sub-questions. The findings indicate five suggestions regarding the overall research question. Firstly, errors should be treated, and always be treated. Secondly, treating errors after finish speaking is the most appropriate time. Thirdly, “errors that may cause problems in an understanding of listener” and “frequent spoken errors” should be treated. Fourthly, repetition and explicit feedback were the most popular types of feedback among males, whereas metalinguistic feedback was the most favoured types amongst females. Finally, teachers were the most preferred person to deliver corrective feedback for the learners. Although the results of the study are difficult to generalize to a larger population, which are Thai EFL learners because of the small sample, the findings provide useful information that may contribute to understanding of SSRUIC learners’ preferences toward error corrections and it might reduce the gap between what teachers employ and what students expect when receiving corrective feedback. The reduction of this gap may be useful for the learning process and could enhance the efforts of both teachers and learners in a Thai context.

Keywords: attitude, corrective feedback, error, preference

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Authors: Saliha Ozcan

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Technology has become an integral part of our lives, aiding individuals in accessing higher order competencies, such as global awareness, creativity, collaborative problem solving, and self-directed learning. Students need to acquire these competencies, often referred to as 21st century skills, in order to adapt to a fast changing world. Today, an ever-increasing number of schools are exploring how engagement through telecollaboration can support language learning and promote 21st century skill development in classrooms. However, little is known regarding how telecollaboration may influence the way students acquire 21st century skills. In this paper, we aim to shed light to the potential implications of telecollaborative practices in acquisition of 21st century skills. In our context, telecollaboration, which might be carried out in a variety of settings both synchronously or asynchronously, is considered as the process of communicating and working together with other people or groups from different locations through online digital tools or offline activities to co-produce a desired work output. The study presented here will describe and analyse the implementation of a telecollaborative project between two high school classes, one in Spain and the other in Sweden. The students in these classes were asked to carry out some joint activities, including creating an online platform, aimed at raising awareness of the situation of the Syrian refugees. We conduct a qualitative study in order to explore how language, culture, communication, and technology merge into the co-construction of knowledge, as well as supporting the attainment of the 21st century skills needed for network-mediated communication. To this end, we collected a significant amount of audio-visual data, including video recordings of classroom interaction and external Skype meetings. By analysing this data, we verify whether the initial pedagogical design and intended objectives of the telecollaborative project coincide with what emerges from the actual implementation of the tasks. Our findings indicate that, as well as planned activities, unplanned classroom interactions may lead to acquisition of certain 21st century skills, such as collaborative problem solving and self-directed learning. This work is part of a wider project (KONECT, EDU2013-43932-P; Spanish Ministry of Economy and Finance), which aims to explore innovative, cross-competency based teaching that can address the current gaps between today’s educational practices and the needs of informed citizens in tomorrow’s interconnected, globalised world.

Keywords: 21st century skills, telecollaboration, language learning, network mediated communication

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Authors: Judith Partouche-Sebban, Saeedeh Rezaee Vessal

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Because of the rising number of new cases of cancer, especially among women, it is more than essential to better understand how women experience cancer in order to bring them adapted to support and care and enhance their well-being and patient experience. Cancer stands for a traumatic experience in which the diagnosis, its medical treatments, and the related side effects lead to deep physical and psychological changes that may arouse considerable stress and anxiety. In order to reduce these negative emotions, women tend to use various defense mechanisms, among which denial has been defined as the most frequent mechanism used by breast cancer patients. This study aims to better understand the consequences of the experience of cancer and their link with the adoption of a denial strategy. The empirical research was done among female cancer survivors in France. Since the topic of this study is relatively unexplored, a qualitative methodology and open-ended interviews were employed. In total, 25 semi-directive interviews were conducted with a female with different cancers, different stages of treatment, and different ages. A systematic inductive method was performed to analyze data. The content analysis enabled to highlight three different denial-related behaviors among women with cancer, which serve a self-protective function. First, women who expressed high levels of anxiety confessed they tended to completely deny the existence of their cancer immediately after the diagnosis of their illness. These women mainly exhibit many fears and a deep distrust toward the medical context and professionals. This coping mechanism is defined by the patient as being unconscious. Second, other women deliberately decided to deny partial information about their cancer, whether this information is related to the stages of the illness, the emotional consequences, or the behavioral consequences of the illness. These women use this strategy as a way to avoid the reality of the illness and its impact on the different aspects of their life as if cancer does not exist. Third, some women tend to reinterpret and give meaning to their cancer as a way to reduce its impact on their life. To this end, they may use magical thinking or positive reframing, or reinterpretation. Because denial may lead to delays in medical treatments, this topic deserves a deep investigation, especially in the context of oncology. As denial is defined as a specific defense mechanism, this study contributes to the existing literature in service marketing which focuses on emotions and emotional regulation in healthcare services which is a crucial issue. Moreover, this study has several managerial implications for healthcare professionals who interact with patients in order to implement better care and support for the patients.

Keywords: cancer, coping mechanisms, denial, healthcare services

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Authors: Seong Woon Lee, Soo Min Lim, Sung Sik Jeong, Jung Hoon Park

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The atmospheric concentration of greenhouse gas (GHG, Green House Gas) is increasing continuously as a result of the combustion of fossil fuels and industrial development. In response to this trend, many researches have been conducted on the reduction of GHG. Landfill gas (LFG, Land Fill Gas) is one of largest sources of GHG emissions containing the methane (CH₄) as a major constituent and can be considered renewable energy sources as well. In order to use LFG by connecting to the city pipe network, it required a process for removing impurities. In particular, oxygen must be removed because it can cause corrosion of pipes and engines. In this study, methane oxidation was used to eliminate oxygen from LFG and perovskite-type ceramic catalysts of La-Sr-Co-Fe-O composition was selected as a catalyst. Hollow fiber catalysts (HFC, Hollow Fiber Catalysts) have attracted attention as a new concept alternative because they have high specific surface area and mechanical strength compared to other types of catalysts. HFC was prepared by a phase-inversion/sintering technique using commercial La-Sr-Co-Fe-O powder. In order to measure the catalysts' activity, simulated LFG was used for feed gas and complete oxidation reaction of methane was confirmed. Pore structure of the HFC was confirmed by SEM image and perovskite structure of single phase was analyzed by XRD. In addition, TPR analysis was performed to verify the oxygen adsorption mechanism of the HFC. Acknowledgement—The project is supported by the ‘Global Top Environment R&D Program’ in the ‘R&D Center for reduction of Non-CO₂ Greenhouse gases’ (Development and demonstration of oxygen removal technology of landfill gas) funded by Korea Ministry of Environment (ME).

Keywords: complete oxidation, greenhouse gas, hollow fiber catalyst, land fill gas, oxygen removal, perovskite catalyst

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Authors: Vijaya Dixit Aasheesh Dixit

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Shipbuilding industry operates in Engineer Procure Construct (EPC) context. Product mix of a shipyard comprises of various types of ships like bulk carriers, tankers, barges, coast guard vessels, sub-marines etc. Each order is unique based on the type of ship and customized requirements, which are engineered into the product right from design stage. Thus, to execute every new project, a shipyard needs to upgrade its production expertise. As a result, over the long run, holistic learning occurs across different types of projects which contributes to the knowledge base of the shipyard. Simultaneously, in the short term, during execution of a project comprising of multiple sister ships, repetition of similar tasks leads to learning at activity level. This research aims to capture above learnings of a shipyard and incorporate learning curve effect in project scheduling and materials procurement to improve project performance. Extant literature provides support for the existence of such learnings in an organization. In shipbuilding, there are sequences of similar activities which are expected to exhibit learning curve behavior. For example, the nearly identical structural sub-blocks which are successively fabricated, erected, and outfitted with piping and electrical systems. Learning curve representation can model not only a decrease in mean completion time of an activity, but also a decrease in uncertainty of activity duration. Sister ships have similar material requirements. The same supplier base supplies materials for all the sister ships within a project. On one hand, this provides an opportunity to reduce transportation cost by batching the order quantities of multiple ships. On the other hand, it increases the inventory holding cost at shipyard and the risk of obsolescence. Further, due to learning curve effect the production scheduled of each consequent ship gets compressed. Thus, the material requirement schedule of every next ship differs from its previous ship. As more and more ships get constructed, compressed production schedules increase the possibility of batching the orders of sister ships. This work aims at integrating materials management with project scheduling of long duration projects for manufacturing of multiple sister ships. It incorporates the learning curve effect on progressively compressing material requirement schedules and addresses the above trade-off of transportation cost and inventory holding and shortage costs while satisfying budget constraints of various stages of the project. The activity durations and lead time of items are not crisp and are available in the form of probabilistic distribution. A Stochastic Mixed Integer Programming (SMIP) model is formulated which is solved using evolutionary algorithm. Its output provides ordering dates of items and degree of order batching for all types of items. Sensitivity analysis determines the threshold number of sister ships required in a project to leverage the advantage of learning curve effect in materials management decisions. This analysis will help materials managers to gain insights about the scenarios: when and to what degree is it beneficial to treat a multiple ship project as an integrated one by batching the order quantities and when and to what degree to practice distinctive procurement for individual ship.

Keywords: learning curve, materials management, shipbuilding, sister ships

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Authors: Janell Jayamohan

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A pilot project based on the Theory of Planned Behavior was completed at a single sex female international high school in order to improve the quality of comprehensive sex education in a 12th grade classroom. The student sample is representative of a growing phenomenon of “Third Culture Kids” or global nomads; often in today’s world, culture transcends any one dominant influence and blends values from multiple sources. The Objective was to improve intentions of condom use during the students’ first or next intercourse. A peer-education session which focused on condom attitudes, social norms, and self-efficacy - central tenets of the Theory of Planned Behavior - was added to an existing curriculum in order to achieve this objective. Peer educators were given liberty of creating and executing the lesson to their homeroom, a sample of 23 senior students, with minimal intervention from faculty, the desired outcome being that the students themselves would be the best judge of what is culturally relevant and important to their peers. The school nurse and school counselor acted as faculty facilitators but did not assist in the creation or delivery of the lesson, only checked for medical accuracy. The participating sample of students completed a pre and post-test with validated questions assessing changes in attitudes and overall satisfaction with the peer education lesson. As this intervention was completed during the Covid-19 pandemic, the peer education session was completed in a virtual classroom environment, limiting the modes of information delivery available to the peer educators, but is planned to be replicated in an in-person environment in subsequent cycles.

Keywords: adolescents, condoms, peer education, sex education, theory of planned behavior, third culture kids

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Authors: Behrang Tavousi Tehrani, Mohammad-Zaman Kabir

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Shape memory alloys (SMA) are often implemented in smart structures as the active components. Their ability to recover large displacements has been used in many applications, including structural stability/response enhancement and active structural acoustic control. SMA wires or fibers can be embedded with composite cylinders to increase their critical buckling load, improve their load-deflection behavior, and reduce the radial deflections under various thermo-mechanical loadings. This paper presents a semi-analytical investigation on the non-linear load-deflection response of SMA-reinforced composite circular cylindrical shells. The cylinder shells are under uniform external pressure load. Based on first-order shear deformation shell theory (FSDT), the equilibrium equations of the structure are derived. One-dimensional simplified Brinson’s model is used for determining the SMA recovery force due to its simplicity and accuracy. Airy stress function and Galerkin technique are used to obtain non-linear load-deflection curves. The results are verified by comparing them with those in the literature. Several parametric studies are conducted in order to investigate the effect of SMA volume fraction, SMA pre-strain value, and SMA activation temperature on the response of the structure. It is shown that suitable usage of SMA wires results in a considerable enhancement in the load-deflection response of the shell due to the generation of the SMA tensile recovery force.

Keywords: airy stress function, cylindrical shell, Galerkin technique, load-deflection curve, recovery stress, shape memory alloy

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Authors: Vânia Graça, Paula Quadros-Flores, Altina Ramos

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The use of Digital Technologies in teaching and learning processes is currently a reality, namely in initial teacher training. This study aims at knowing the digital reality of students in initial teacher training in order to improve training in the educational use of ICT and to promote digital technology integration strategies in an educational context. It is part of the IFITIC Project "Innovate with ICT in Initial Teacher Training to Promote Methodological Renewal in Pre-school Education and in the 1st and 2nd Basic Education Cycle" which involves the School of Education, Polytechnic of Porto and Institute of Education, University of Minho. The Project aims at rethinking educational practice with ICT in the initial training of future teachers in order to promote methodological innovation in Pre-school Education and in the 1st and 2nd Cycles of Basic Education. A qualitative methodology was used, in which a questionnaire survey was applied to teachers in initial training. For data analysis, the techniques of content analysis with the support of NVivo software were used. The results point to the following aspects: a) future teachers recognize that they have more technical knowledge about ICT than pedagogical knowledge. This result makes sense if we consider the objective of Basic Education, so that the gaps can be filled in the Master's Course by students who wish to follow the teaching; b) the respondents are aware that the integration of digital resources contributes positively to students' learning and to the life of children and young people, which also promotes preparation in life; c) to be a teacher in the digital age there is a need for the development of digital literacy, lifelong learning and the adoption of new ways of teaching how to learn. Thus, this study aims to contribute to a reflection on the teaching profession in the digital age.

Keywords: digital technologies, initial teacher training, pedagogical use of ICT, skills

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Authors: Caroline S. Dutra, Tatiana C. Squeff

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It is well known that the history between South Korea and Japan influences their international relations; thus, also encompassing their economic relations. In this sense, it is impossible to analyze the latter without understanding the development of the former, which is known for episodes of hostility, like on Japanese colonization, but also had moments of cultural and trade interexchange. Indeed, since 1965, with the establishment of diplomatic relations between both countries, their trade relations have improved, especially after both nations have signed the General Agreement on Tariffs and Trade (GATT). Thereafter, with the establishment of the World Trade Organization (WTO) in 1995, another chapter of their diplomatic and economic relations have been inaugurated. Hence, bearing in mind this history between both nations, this research intends to examine their relations through the analysis of the WTO panels they have engaged in between each other, which are, in chronological order, “DS323: Japan – Import Quotas on Dried Laver and Seasoned Laver”, “DS336: Japan - Countervailing Duties on Dynamic Random Access Memories from Korea”, “DS495: Korea - Import Band, and Testing and Certification Requirements for Radionuclides”, “DS553: Korea - Sunset Review of Anti-Dumping Duties on Stainless Steel Bars” and “DS571: Korea - Measures Affecting Trade in Commercial Vessels”. The objective of this case analysis is to point out what are the areas that are more conflictual between Japan and South Korea in regard to their economic relations so that it is possible to assert on their future (economic) relations and other possible outcomes. And in order to do so, bibliographic and documental research will be made, particularly those involving the WTO and the nations under consideration. Regarding the methods used, it is important to highlight that this is applied research in the field of international economic relations and international law, which follows a hypothetic-deductive model.

Keywords: international economic relations, Japan, South Korea, World Trade Organization

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Authors: Nidal Ali

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Consider an algebraic number field K of degree n, A0 K is its ring of integers and a prime number p inert in K. Let F(u1, . . . , un, x) be the generic polynomial of integers of K. We will study in advance the stability of this polynomial and then, we will apply it in order to obtain all the monic irreducible polynomials in Fp[x] of degree d dividing n.

Keywords: generic polynomial, irreducibility, iteration, stability, inert prime, totally ramified

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Authors: V. Samulionis, J. Banys, A. Sánchez-Ferrer

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Inorganic nanoparticles are used for fabrication of various composites based on polymer materials because they exhibit a good homogeneity and solubility of the composite material. Multifunctional materials based on composites of a polymer containing inorganic nanotubes are expected to have a great impact on industrial applications in the future. An emerging family of such composites are polyurea elastomers with inorganic MoS2 nanotubes or MoSI nanowires. Polyurea elastomers are a new kind of materials with higher performance than polyurethanes. The improvement of mechanical, chemical and thermal properties is due to the presence of hydrogen bonds between the urea motives which can be erased at high temperature softening the elastomeric network. Such materials are the combination of amorphous polymers above glass transition and crosslinkers which keep the chains into a single macromolecule. Polyurea exhibits a phase separated structure with rigid urea domains (hard domains) embedded in a matrix of flexible polymer chains (soft domains). The elastic properties of polyurea can be tuned over a broad range by varying the molecular weight of the components, the relative amount of hard and soft domains, and concentration of nanoparticles. Ultrasonic methods as non-destructive techniques can be used for elastomer composites characterization. In this manner, we have studied the temperature dependencies of the longitudinal ultrasonic velocity and ultrasonic attenuation of these new polyurea elastomers and composites with inorganic nanoparticles. It was shown that in these polyurea elastomers large ultrasonic attenuation peak and corresponding velocity dispersion exists at 10 MHz frequency below room temperature and this behaviour is related to glass transition Tg of the soft segments in the polymer matrix. The relaxation parameters and Tg depend on the segmental molecular weight of the polymer chains between crosslinking points, the nature of the crosslinkers in the network and content of MoS2 nanotubes or MoSI nanowires. The increase of ultrasonic velocity in composites modified by nanoparticles has been observed, showing the reinforcement of the elastomer. In semicrystalline polyurea elastomer matrices, above glass transition, the first order phase transition from quasi-crystalline to the amorphous state has been observed. In this case, the sharp ultrasonic velocity and attenuation anomalies were observed near the transition temperature TC. Ultrasonic attenuation maximum related to glass transition was reduced in quasicrystalline polyureas indicating less influence of soft domains below TC. The first order phase transition in semicrystalline polyurea elastomer samples has large temperature hysteresis (> 10 K). The impact of inorganic MoS2 nanotubes resulted in the decrease of the first order phase transition temperature in semicrystalline composites.

Keywords: inorganic nanotubes, polyurea elastomer composites, ultrasonic velocity, ultrasonic attenuation

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Authors: Jacob Medupe

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Life as we know it has changed since the global outbreak of Coronavirus Disease 2019 (COVID-19) and business as usual will not continue. The human impact of the COVID-19 crisis is already immeasurable. Moreover, COVID-19 has already negatively impacted economies, livelihoods and disrupted food systems around the world. The disruptive nature of the Corona virus has affected every sphere of life including the culture and teaching and learning. Right now the majority of education research is based around classroom management techniques that are no longer necessary with digital delivery. Instead there is a great need for new data about how to make the best use of the one-on-one attention that is now becoming possible (Diamandis & Kotler, 2014). The COVID-19 pandemic has necessitated an environment where the South African learners are focused to adhere to social distancing in order to minimise the wild spread of the Corona virus. This arrangement forces the student to utilise the online classroom technologies to continue with the lessons. The historical reality is that the country has not made much strides on the closing of the digital divide and this is particularly a common status quo in the deep rural areas. This will prove to be a toll order for most of the learners affected by the Corona Virus to be able to have a seamless access to the online learning facilities. The paper will seek to look deeply into this reality and how the Corona virus has brought us to the reality that South Africa remains a deeply unequal society in every sphere of life. The study will also explore the state of readiness for education system around the online classroom environment.

Keywords: virtual learning, virtual classroom, COVID-19, Corona virus, internet connectivity, blended learning, online learning, distance education, e-learning, self-regulated Learning, pedagogy, digital literacy

Procedia PDF Downloads 114