Search results for: electromagnetics fully-coupled dynamics

Authors: Baha-Aldeen S. Algmati, Ahmed R. Ballil

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Multiphase flows occur widely in many engineering and industrial processes as well as in the environment we live in. In particular, bubbly flows are considered to be crucial phenomena in fluid flow applications and can be studied and analyzed experimentally, analytically, and computationally. In the present paper, the dynamic motion of an air bubble rising within a column of liquid is numerically simulated using an open-source CFD modeling tool 'OpenFOAM'. An interface tracking numerical algorithm called MULES algorithm, which is built-in OpenFOAM, is chosen to solve an appropriate mathematical model based on the volume of fluid (VOF) numerical method. The bubbles initially have a spherical shape and starting from rest in the stagnant column of liquid. The algorithm is initially verified against numerical results and is also validated against available experimental data. The comparison revealed that this algorithm provides results that are in a very good agreement with the 2D numerical data of other CFD codes. Also, the results of the bubble shape and terminal velocity obtained from the 3D numerical simulation showed a very good qualitative and quantitative agreement with the experimental data. The simulated rising bubbles yield a very small percentage of error in the bubble terminal velocity compared with the experimental data. The obtained results prove the capability of OpenFOAM as a powerful tool to predict the behavior of rising characteristics of the spherical bubbles in the stagnant column of liquid. This will pave the way for a deeper understanding of the phenomenon of the rise of bubbles in liquids.

Keywords: CFD simulations, multiphase flows, OpenFOAM, rise of bubble, volume of fluid method, VOF

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Authors: Otu Otu Akanu

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The nexus between migration, national security, and human rights has become increasingly complex, particularly within Nigeria's geopolitical landscape. This study explores how Nigeria navigates the balance between safeguarding national security and upholding human rights amidst escalating regional crises, such as conflicts in the Lake Chad Basin and the Sahel. Through a comprehensive analysis of policy frameworks, security measures, and human rights protocols, this paper critically examines the challenges and opportunities in Nigeria's approach. The study employed a multidisciplinary methodology, integrating perspectives from International Relations, Human Security Studies, and Migration Law to provide a holistic understanding of the issue. Drawing on primary data from government reports, policy documents, and interviews with key stakeholders, alongside secondary literature, the study reveals a persistent tension between security imperatives and human rights obligations. While Nigeria has made strides in enhancing its security architecture, the findings highlight significant gaps in the protection of migrants' rights, often exacerbated by external pressures and domestic political dynamics. The paper argues that a recalibration of Nigeria's security and human rights policies is imperative for achieving sustainable peace and security in the region. By offering policy recommendations rooted in international best practices, this study contributes to the ongoing discourse on migration and security in West Africa and provides a framework for other nations grappling with similar challenges. This research underscores the need for an integrated approach that transcends traditional security paradigms, advocating a more inclusive and human-centered strategy in addressing the complexities of migration and national security.

Keywords: migration, national security, human rights, Nigeria, West Africa

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Authors: Alaa Sarhan, Rania Abd El Gelil, Hana Awad

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Through the last decades, the impact of thermal comfort on the working performance of users and occupants of an indoor space has been a concern. Research papers concluded that natural ventilation quality directly impacts the levels of thermal comfort. Natural ventilation must be put into account during the design process in order to improve the inhabitant's efficiency and productivity. One example of daily long-term occupancy spaces is educational facilities. Many individuals spend long times receiving a considerable amount of knowledge, and it takes additional time to apply this knowledge. Thus, this research is concerned with user's level of thermal comfort in design studios of educational facilities. The natural ventilation quality in spaces is affected by a number of parameters including orientation, opening design, and many other factors. This research aims to investigate the conscious manipulation of the physical parameters of the spaces and its impact on natural ventilation performance which subsequently affects thermal comfort of users. The current research uses inductive and deductive methods to define natural ventilation design considerations, which are used in a field study in a studio in the university building in Alexandria (AAST) to evaluate natural ventilation performance through analyzing and comparing the current case to the developed framework and conducting computational fluid dynamics simulation. Results have proved that natural ventilation performance is successful by only 50% of the natural ventilation design framework; these results are supported by CFD simulation.

Keywords: educational buildings, natural ventilation, , mediterranean climate, thermal comfort

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Authors: Claudia Ehrentraut, Osama Ibrahim, Hercules Dalianis

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Policy making situations are real-world problems that exhibit complexity in that they are composed of many interrelated problems and issues. To be effective, policies must holistically address the complexity of the situation rather than propose solutions to single problems. Formulating and understanding the situation and its complex dynamics, therefore, is a key to finding holistic solutions. Analysis of text based information on the policy problem, using Natural Language Processing (NLP) and Text analysis techniques, can support modelling of public policy problem situations in a more objective way based on domain experts knowledge and scientific evidence. The objective behind this study is to support modelling of public policy problem situations, using text analysis of verbal descriptions of the problem. We propose a formal methodology for analysis of qualitative data from multiple information sources on a policy problem to construct a causal diagram of the problem. The analysis process aims at identifying key variables, linking them by cause-effect relationships and mapping that structure into a graphical representation that is adequate for designing action alternatives, i.e., policy options. This study describes the outline of an algorithm used to automate the initial step of a larger methodological approach, which is so far done manually. In this initial step, inferences about key variables and their interrelationships are extracted from textual data to support a better problem structuring. A small prototype for this step is also presented.

Keywords: public policy, problem structuring, qualitative analysis, natural language processing, algorithm, inference extraction

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Authors: Tytus Tulwin, Ksenia Siadkowska, Rafał Sochaczewski

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A high power radial reciprocating engine is characterized by a large displacement volume of a combustion chamber. Choosing the right moment for ignition is important for a high performance or high reliability and ignition certainty. This work shows methods of simulating ignition process and its impact on engine parameters. For given conditions a flame speed is limited when a deflagration combustion takes place. Therefore, a larger length scale of the combustion chamber compared to a standard size automotive engine makes combustion take longer time to propagate. In order to speed up the mixture burn-up time the second spark is introduced. The transient Computational Fluid Dynamics model capable of simulating multicycle engine processes was developed. The CFD model consists of ECFM-3Z combustion and species transport models. A relative ignition timing difference for the both spark sources is constant. The temperature distribution on engine walls was calculated in the separate conjugate heat transfer simulation. The in-cylinder pressure validation was performed for take-off power flight conditions. The influence of ignition timing on parameters like in-cylinder temperature or rate of heat release was analyzed. The most advantageous spark timing for the highest power output was chosen. The conditions around the spark plug locations for the pre-ignition period were analyzed. This work has been financed by the Polish National Centre for Research and Development, INNOLOT, under Grant Agreement No. INNOLOT/I/1/NCBR/2013.

Keywords: CFD, combustion, ignition, simulation, timing

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Authors: Gianni Jacucci

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We present a retrospective on the development of a research group over the past 30+ years. We reflect on a change in observing the experience (1990-2024) of a university sociotechnical research group dedicated to instill change for innovation in client organisations and enterprises. Its cognitive and action trajectory is influenced by subjective factors: intention and interpretation. Continuity and change are both present: the trajectory of the group exhibits the dynamic interplay of two components of subjectivity, a change of focus in persistence of scheme, and a tension between stability and change. The paper illustrates the meanings the group gave to their practice while laying down mission-critical theoretical considerations – autopoiesis-. The aim of the work is to experience a fragment of phenomenological understanding (PU) of the cognitive dynamics of an STS-aware ICT uptake Laboratory during the digital revolution. PU is an intuitive going along the meaning, while staying close and present to the total situation of the phenomenon. Reading the codes that we observers invent in order to codify what nature is about, thus unveiling subconscious, autopoietic, reflexive feedback mechanisms of second order governance from work published over three decades by the ICT Lab, as if it were the narration of its cognitive autobiography. The paper brings points of discussion and insights of relevance for the STS community. It could be helpful in understanding the history of the community and in providing a platform for discussions on future developments. It can also serve as an inspiration and a historical capture for those entering the field.

Keywords: phenomenology, subjectivity, autopoiesis, interpretation schemes, change for innovation, socio technical research, social study of information systems

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Authors: Einav Srulovici, Michal Grinstein-Weiss, George Knafl, Linda Beeber, Shawn Kneipp, Barbara Mark

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Background: The asset-building theoretical framework (ABTF) is acknowledged as the most complete framework thus far for depicting the relationships between asset accumulation (the stock of a household’s saved resources available for future investment) and health outcomes. Although the ABTF takes into consideration the reciprocal relationship between asset accumulation and health, no ABTF based study has yet examined this relationship. Therefore, the purpose of this study was to test the ABTF and psychological distress, focusing on the reciprocal relationship between assets accumulation and psychological distress. Methods: The study employed longitudinal data from 6,295 families from the 2001 and 2007 Panel Study of Income Dynamics data sets. Structural equation modeling (SEM) was used to test the reciprocal relationship between asset accumulation and psychological distress. Results: In general, the data displayed a good fit to the model. The longitudinal SEM found that asset accumulation significantly increased with a decreased in psychological distress over time, while psychological distress significantly increased with an increase in asset accumulation over time, confirming the existence of the hypothesized reciprocal relationship. Conclusions: Individuals who are less psychological distressed might have more energy to engage in activities, such as furthering their education or obtaining better jobs that are in turn associated with greater asset accumulation, while those who have greater assets may invest those assets in riskier investments, resulting in increased psychological distress. The confirmation of this reciprocal relationship highlights the importance of conducting longitudinal studies and testing the reciprocal relationship between asset accumulation and other health outcomes.

Keywords: asset-building theoretical framework, psychological distress, structural equation modeling, reciprocal relationship

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Authors: Lanka Dinushke Weerasiri, Subrat Das, Daniel Fabijanic, William Yang

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Fluidization at vacuum pressure has been a topic that is of growing research interest. Several industrial applications (such as drying, extractive metallurgy, and chemical vapor deposition (CVD)) can potentially take advantage of vacuum pressure fluidization. Particularly, the fine chemical industry requires processing under safe conditions for thermolabile substances, and reduced pressure fluidized beds offer an alternative. Fluidized beds under vacuum conditions provide optimal conditions for treatment of granular materials where the reduced gas pressure maintains an operational environment outside of flammability conditions. The fluidization at low-pressure is markedly different from the usual gas flow patterns of atmospheric fluidization. The different flow regimes can be characterized by the dimensionless Knudsen number. Nevertheless, hydrodynamics of bubbling vacuum fluidized beds has not been investigated to author’s best knowledge. In this work, the two-fluid numerical method was used to determine the impact of reduced pressure on the fundamental properties of a fluidized bed. The slip flow model implemented by Ansys Fluent User Defined Functions (UDF) was used to determine the interphase momentum exchange coefficient. A wide range of operating pressures was investigated (1.01, 0.5, 0.25, 0.1 and 0.03 Bar). The gas was supplied by a uniform inlet at 1.5U_mf and 2U_mf. The predicted minimum fluidization velocity (U_mf) shows excellent agreement with the experimental data. The results show that the operating pressure has a notable impact on the bed properties and its hydrodynamics. Furthermore, it also shows that the existing Gorosko correlation that predicts bed expansion is not applicable under reduced pressure conditions.

Keywords: computational fluid dynamics, fluidized bed, gas-solid flow, vacuum pressure, slip flow, minimum fluidization velocity

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Authors: T. A. Rosy, M. R. I. Talukdar, N. S. Juyena, F. Y. Bari, M. N. Islam

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The ovarian follicular dynamics, vaginal electrical resistance (VER) and progesterone (P4) and estrogen (E2) profiles were investigated during estrus cycle in four indigenous ewes. Daily VER values were recorded with heat detector. The follicles were observed and measured by trans-rectal ultrasonography. Blood was collected daily for hormonal profiles. Results showed a significant variation in VER values (P<0.05) at estrus in regards to ewes and cycles. The day difference between two successive lower values in VER waves ranged from 13-17 days which might indicate the estrus cycle in indigenous ewes. Trans-rectal ultrasonography of ovaries revealed the presence of two to four waves of follicular growth during the study period. Results also showed that follicular diameter was negatively correlated with VER values. Study of hormonal profiles by ELISA revealed a positive correlation between E2 concentration and development of follicle and negative correlation between P4 concentration and development of follicle. The concentrations of estradiol increased at the time of estrus and then fall down in a basal level. Development of follicular size was accompanied by an increase in the concentration of serum estradiol. Inversely, when follicles heed to ovulation concentration of progesterone starts to fall down and after ovulation it turns its way to the zenith and remains at this state until next ovulatory follicle comes to its maximum diameter. This study could help scientists to set up a manipulative reproductive technique for improving genetic values of sheep in Bangladesh.

Keywords: ovarian follicle, hormonal profile, sheep, ultrasonography, vaginal electrical resistance

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Authors: A. Bensaid, T. Mostephaoui, R. Nedjai

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A considerable area of Algerian lands is threatened by the phenomenon of wind erosion. For a long time, wind erosion and its associated harmful effects on the natural environment have posed a serious threat, especially in the arid regions of the country. In recent years, as a result of increases in the irrational exploitation of natural resources (fodder) and extensive land clearing, wind erosion has particularly accentuated. The extent of degradation in the arid region of the Algerian Mecheria department generated a new situation characterized by the reduction of vegetation cover, the decrease of land productivity, as well as sand encroachment on urban development zones. In this study, we attempt to investigate the potential of remote sensing and geographic information systems for detecting the spatial dynamics of the ancient dune cords based on the numerical processing of LANDSAT images (5, 7, and 8) of three scenes 197/37, 198/36 and 198/37 for the year 2020. As a second step, we prospect the use of geospatial techniques to monitor the progression of sand dunes on developed (urban) lands as well as on the formation of sandy accumulations (dune, dunes fields, nebkha, barkhane, etc.). For this purpose, this study made use of the semi-automatic processing method for the dynamic segmentation of images with very high spatial resolution (SENTINEL-2 and Google Earth). This study was able to demonstrate that urban lands under current conditions are located in sand transit zones that are mobilized by the winds from the northwest and southwest directions.

Keywords: land development, GIS, segmentation, remote sensing

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Authors: Matjaz Prek

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Impact of three different combinations of cooling and ventilation systems on the indoor environmental quality (IEQ) has been studied. Comparison of chilled ceiling cooling in combination with displacement ventilation, cooling with fan coil unit and cooling with flat wall displacement outlets was performed. All three combinations were evaluated from the standpoint of whole-body and local thermal comfort criteria as well as from the standpoint of ventilation effectiveness. The comparison was made on the basis of numerical simulation with DesignBuilder and Fluent. Numerical simulations were carried out in two steps. Firstly the DesignBuilder software environment was used to model the buildings thermal performance and evaluation of the interaction between the environment and the building. Heat gains of the building and of the individual space, as well as the heat loss on the boundary surfaces in the room, were calculated. In the second step Fluent software environment was used to simulate the response of the indoor environment, evaluating the interaction between building and human, using the simulation results obtained in the first step. Among the systems presented, the ceiling cooling system in combination with displacement ventilation was found to be the most suitable as it offers a high level of thermal comfort with adequate ventilation efficiency. Fan coil cooling has proved inadequate from the standpoint of thermal comfort whereas flat wall displacement outlets were inadequate from the standpoint of ventilation effectiveness. The study showed the need in evaluating indoor environment not solely from the energy use point of view, but from the point of view of indoor environmental quality as well.

Keywords: cooling, ventilation, thermal comfort, ventilation effectiveness, indoor environmental quality, IEQ, computational fluid dynamics

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Authors: Ana C. V. Freitas, Luciana B. M. Pires, Joao P. Martins

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In recent years, fire dynamics in deforestation areas of tropical forests have received considerable attention because of their relationship to climate change. Climate models project great increases in the frequency and area of drought in the Amazon region, which may increase the occurrence of fires. This study analyzes the historical record number of fire outbreaks in 2017 using satellite-derived data sets of active fire detections, burned area, precipitation, and data of the Fire Program from the Center for Weather Forecasting and Climate Studies (CPTEC/INPE). A downward trend in the number of fire outbreaks occurred in the first half of 2017, in relation to the previous year. This decrease can be related to the fact that 2017 was not an El Niño year and, therefore, the observed rainfall and temperature in the Amazon region was close to normal conditions. Meanwhile, the worst period in history for fire outbreaks began with the subsequent arrival of the dry season. September of 2017 exceeded all monthly records for number of fire outbreaks per month in the entire series. This increase was mainly concentrated in Bolivia and in the states of Amazonas, northeastern Pará, northern Rondônia and Acre, regions with high densities of rural settlements, which strongly suggests that human action is the predominant factor, aggravated by the lack of precipitation during the dry season allowing the fires to spread and reach larger areas. Thus, deforestation in the Amazon is primarily a human-driven process: climate trends may be providing additional influences.

Keywords: Amazon forest, climate change, deforestation, human-driven process, fire outbreaks

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Authors: Rowena Clemino Alcoba

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Thailand is host to the largest number of refugees in the region. The country has been one of the most accessible points of entry to refugees around the world because it has relatively lenient visa requirements, enabling asylum seekers to enter the country and subsequently search for legal assistance. However, because Thailand is not a signatory to the 1951 Geneva Convention on Refugees which governs the refugee status determination and safeguards several rights of the refugees, there are no national laws or administrative framework on the protection of refugees. Refugees are considered as illegal migrants, and certain groups are permitted to stay temporarily only upon executive discretion. Aside from the documented group of refugees from the Myanmar border, there are many others who came from different parts of the world. They are known as urban refugees believed to be in the thousands and are scattered in the impoverished areas of Bangkok and the suburbs. This study aims to advance understanding of the role of civil society organizations in supporting refugees, with particular focus on urban refugees. Using the method of triangulation in qualitative research, the study investigates the life journey of a refugee family from Pakistan, their difficulties and struggles to survive in perilous situations. The study presents the dynamics of how civil society works and collaborates to fill the gap for much-needed social services. It also discusses the depth and scope of the role of faith actors in the protection and support of this vulnerable sector. The engagement of civil society reveals framework and structure that aims to create long-term impact. The help provided is not merely monetary or material dole-outs but a platform for refugees to integrate with community, develop skills and make productive use of their time.

Keywords: asylum seeker, civil society, faith actors, refugees

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Authors: Hossein Askarinejad, Manicka Dhanasekar

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In railway tracks, two adjacent rails are either welded or connected using bolted jointbars. In recent years the number of bolted rail joints is reduced by introduction of longer rail sections and by welding the rails at location of some joints. However, significant number of bolted rail joints remains in railways around the world as they are required to allow for rail thermal expansion or to provide electrical insulation in some sections of track. Regardless of the quality and integrity of the jointbar and bolt connections, the bending stiffness of jointbars is much lower than the rail generating large deflections under the train wheels. In addition, the gap or surface discontinuity on the rail running surface leads to generation of high wheel-rail impact force at the joint gap. These fundamental weaknesses have caused high rate of failure in track components at location of rail joints resulting in significant economic and safety issues in railways. The mechanical behavior of railway track at location of joints has not been fully understood due to various structural and material complexities. Although there have been some improvements in the methods for analysis of track at jointed rails in recent years, there are still uncertainties concerning the accuracy and reliability of the current methods. In this paper the current methods in analysis of track with a rail joint are critically evaluated and the new advances and recent research outcomes in this area are discussed. This research is part of a large granted project on rail joints which was defined by Cooperative Research Centre (CRC) for Rail Innovation with supports from Australian Rail Track Corporation (ARTC) and Queensland Rail (QR).

Keywords: jointed rails, railway mechanics, track dynamics, wheel-rail interaction

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Authors: Yogendra K. Karna, Lauren T. Bennett

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Fire-tolerant eucalypt forests are one of the major forest ecosystems of south-eastern Australia and thought to be highly resistant to frequent high severity wildfires. However, the impact of different severity wildfires on the canopy structure of fire-tolerant forest type is under-studied, and there are significant knowledge gaps in relation to the assessment of tree and stand level canopy structural dynamics and recovery after fire. Assessment of canopy structure is a complex task involving accurate measurements of the horizontal and vertical arrangement of the canopy in space and time. This study examined the utility of multitemporal, small-footprint lidar data to describe the changes in the horizontal and vertical canopy structure of fire-tolerant eucalypt forests seven years after wildfire of different severities from the tree to stand level. Extensive ground measurements were carried out in four severity classes to describe and validate canopy cover and height metrics as they change after wildfire. Several metrics such as crown height and width, crown base height and clumpiness of crown were assessed at tree and stand level using several individual tree top detection and measurement algorithm. Persistent effects of high severity fire 8 years after both on tree crowns and stand canopy were observed. High severity fire increased the crown depth but decreased the crown projective cover leading to more open canopy.

Keywords: canopy gaps, canopy structure, crown architecture, crown projective cover, multi-temporal lidar, wildfire severity

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Authors: Upasana Ranjib

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Sports psychology, as a niche area, has, since the last two decades, found for itself a space within the outer peripheries of the discipline of traditional psychology. It has aimed to understand the many variables that push athletes to enhance their performances. While sociological aspects have been duly represented in academia, little has been written about the role of culture in shaping the psyche of athletes. The impact that cultures of different communities and societies have towards specifics like gender, castes, religion and race and how that helps evolve an individual has not been fully addressed. In the case of Sport, culture has made itself felt in the form of stereotypes, traditional outlooks towards sects and its implication on the engagement with sports. Culture is an environment that an individual imbibes. It is what shapes him, physically as well as mentally. Their nurture and nature both stem from it and depend on it. To realize the linkages between their nurture, nature and sports efficiency, cultural studies must collaborate in scholarship with psychology and practical sports. Cultural sports psychology would allow sports psychologists, coaches and even athletes themselves to understand the behavioural variations that affect their performance. The variations in the performance of athletes from different cultures and countries could be attributed to their socio-political, economic and environmental differences. These cultural influences shape and impact the athlete's behaviour and might lead as a gateway to understanding their skill sets and internal motivational factors. With that knowledge in mind, this paper aims to understand and reflect on how, in the present times of heavy sporting competition, shifting cultural equations and changing world dynamics, it is mandatory to infuse Cultural Studies with Sports Psychology to understand how Sports Psychologists can help and augment the performances of athletes.

Keywords: sporting performance, Asian sports, sports psychology, cultural psychology, society

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Authors: Chong Zhang

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There is widespread debate about the nationalistic top-down approach to citizenship education. Employing the notion of cultural citizenship as a useful theoretical lens, citizenship education research tends to focus on the process of subjectivity construction among students’ citizenship learning process. As the Communist Party of China (CPC) plays a dominant role in cultivating citizens through ideological and political education (IaPE) in Chinese universities, the research problem herein focuses on the dynamics and complexity of how Chinese university students construct their subjectivities regarding citizenship learning through IaPE, mediated by the interaction between the state and university teachers. Drawing on questionnaire data from 212 students and interview data from 25 students in one university in China, this paper examines the ways in which students understand and respond to dominant discourses. Its findings reveal there is a deficit of citizenship learning in IaPE, and that students feel ideologically pressurized. From its analysis of social contexts’ influence, the article suggests Chinese higher education students act as either mild changemakers or active self-motivators to enact complex subjectivities, in that they must involve themselves in IaPE for personal academic and career development, yet adopt covert strategies to realise their self-conscious citizenship learning expectations. These strategies take the form of passive and active freedoms, ranging from obediently completing basic curriculum requirements and distancing themselves by studying abroad, to actively searching for learning opportunities from other courses and social media. This paper contributes to the research on citizenship education by recognizing the complexities of how subjectivities are formed in formal university settings.

Keywords: university students, citizenship learning, cultural citizenship, subjectivity, Chinese higher education

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Authors: Pratibha Biswal, Suyash Morchhale, Anshuman Singh Yadav, Shubham Sanjay Chobe

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Energy demands are increasing whereas energy sources, especially non-renewable sources are limited. Due to the intermittent nature of renewable energy sources, it has become the need of the hour to find new ways to store energy. Out of various energy storage methods, latent heat thermal storage devices are becoming popular due to their high energy density per unit mass and volume at nearly constant temperature. This work presents a computational fluid dynamics (CFD) model using ANSYS FLUENT 19.0 for energy storage characteristics of a phase change material (PCM) filled in a vertical triplex tube thermal energy storage system. A vertical triplex tube heat exchanger, just like its name consists of three concentric tubes (pipe sections) for parting the device into three fluid domains. The PCM is filled in the middle domain with heat transfer fluids flowing in the outer and innermost domains. To enhance the heat transfer inside the PCM, eight fins have been incorporated between the internal and external tubes. These fins run radially outwards from the outer-wall of innermost tube to the inner-wall of the middle tube dividing the middle domain (between innermost and middle tube) into eight sections. These eight sections are then filled with a PCM. The validation is carried with earlier work and a grid independence test is also presented. Further studies on freezing and melting process were carried out. The results are presented in terms of pictorial representation of isotherms and liquid fraction

Keywords: heat exchanger, thermal energy storage, phase change material, CFD, latent heat

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Authors: Mohammed Alanazi, Dimitrios Tsagdis

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Established Business Excellence Models (BEMs), like the Malcolm Baldrige National Quality Award (MBNQA) model and the European Foundation for Quality Management (EFQM) model, have been adopted by firms all over the world. They exist alongside more recent country-specific BEMs; e.g. the Australian, Canadian, China, New Zealand, Singapore, and Taiwan quality awards that although not as widespread as MBNQA and EFQM have nonetheless strong national followings. Regardless of any differences in their following or prestige, the emergence and development of all BEMs have been shaped both by their local context (e.g. underlying socio-economic dynamics) as well as by global best practices. Besides such similarities, that render them into objects (i.e. models) of the same class (i.e. BEMs), BEMs exhibit non-trivial differences in their criteria, relations, and emphasis. Given the evolution of BEMs (e.g. the MBNQA underwent seven evolutions since its inception in 1987 while the EFQM five since 1993), it is unsurprising that comparative studies of their validity are few and far in between. This poses challenges for practitioners and policy makers alike; as it is not always clear which BEM is to be preferred or better fitting to a particular context. Especially, in contexts that differ substantially from the original context of BEM development. This paper aims to fill this gap by presenting a research design and measurement model for comparing BEMs using quantitative methods (e.g. structural equations). Three BEMs will be focused upon in particular for illustration purposes; the MBNQA, the EFQM, and the King Abdul Aziz Quality Award (KAQA) model. They have been selected so to reflect the two established and widely spread traditions as well as a more recent context-specific arrival promising a better fit.

Keywords: Baldrige, business excellence, European Foundation for Quality Management, Structural Equation Model, total quality management

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Authors: Masoud Safdari, Jacob Fish

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Despite vast amount of existing theoretical knowledge, the implementation of a universal multiscale modeling, analysis, and simulation software framework remains challenging. Existing multiscale software and solutions are often domain-specific, closed-source and mandate a high-level of experience and skills in both multiscale analysis and programming. Furthermore, tools currently existing for Atomistic-to-Continuum (AtC) multiscaling are developed with the assumptions such as accessibility of high-performance computing facilities to the users. These issues mentioned plus many other challenges have reduced the adoption of multiscale in academia and especially industry. In the current work, we introduce Multiscale Hub (MsHub), an effort towards making AtC more accessible through cloud services. As a joint effort between academia and industry, MsHub provides a universal web-enabled framework for practical multiscaling. Developed on top of universally acclaimed scientific programming language Python, the package currently provides an open-source, comprehensive, easy-to-use framework for AtC coupling. MsHub offers an easy to use interface to prominent molecular dynamics and multiphysics continuum mechanics packages such as LAMMPS and MFEM (a free, lightweight, scalable C++ library for finite element methods). In this work, we first report on the design philosophy of MsHub, challenges identified and issues faced regarding its implementation. MsHub takes the advantage of a comprehensive set of tools and algorithms developed for AtC that can be used for a variety of governing physics. We then briefly report key AtC algorithms implemented in MsHub. Finally, we conclude with a few examples illustrating the capabilities of the package and its future directions.

Keywords: atomistic, continuum, coupling, multiscale

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Authors: Ivan D. Ortega, Juan D. Castro, Alberto Pertuz, Manuel Martinez

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One of the problems considered when scientists talk about climate change is the necessity of utilizing renewable sources of energy, on this category there are many approaches to the problem, one of them is wind energy and wind turbines whose designs have frequently changed along many years trying to achieve a better overall performance on different conditions. From that situation, we get the two main types known today: Vertical and Horizontal axis wind turbines, which have acronyms VAWT and HAWT, respectively. This research aims to understand how well suited a composite material, which is still in development, made with natural origin fibers is for its implementation on vertical axis wind turbines blades under certain wind loads. The study consisted on acquiring the mechanical properties of the materials to be used which where bactris guineenis, also known as pama de lata in Colombia, and adhesive that acts as the matrix which had not been previously studied to the point required for this project. Then, a simplified 3D model of the airfoil was developed and tested under some preliminary loads using finite element analysis (FEA), these loads were acquired in the Colombian Chicamocha Canyon. Afterwards, a more realistic pressure profile was obtained using computational fluid dynamics which took into account the 3D shape of the complete blade and its rotation. Finally, the blade model was subjected to the wind loads using what is known as one way fluidstructure interaction (FSI) and its behavior analyzed to draw conclusions. The observed overall results were positive since the material behaved fairly as expected. Data suggests the material would be really useful in this kind of applications in small to medium size turbines if it is given more attention and time to develop.

Keywords: CFD, FEA, FSI, natural fiber, VAWT

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Authors: Charles Deodat Otami

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This paper documents an ongoing investigation which seeks to explore the consequences of repeated science curriculum reforms at basic level of education in Ghana. Drawing upon data collected through document analysis, semi-structured interviews and classroom observations linked with a study of teaching practices in Junior High Schools of educational districts that are well served with teachers and yet, produce poor students’ achievements in science in the national Basic Education Certificate Examinations. The results emanating from the investigation highlight that the repeated science curriculum reforms at the basic level of education have led to the displacement of scientific knowledge in junior high schools in Ghana, a very critical level of education where the foundation for further science education to the highest level is laid. Furthermore, the results indicate that the enactment of centralised curriculum reforms in Ghana has produced some unpleasant repercussions. For instance, how the teachers interpret and implement the curriculum is directly related to their own values and practices as well as students feedback. This is contrary to the perception that external impetus received from donor agencies holds the key to strengthening reforms made. Thus, it is argued that without the right of localised management, curriculum reforms themselves are inadequate to ensure the realisation of the desired effects. This paper, therefore, draws the attention of stakeholders to the fact that the enactment of School Science Curriculum reform goes beyond just simple implementation to more complex dynamics which may change the original reform intents.

Keywords: basic education, basic education certificate examinations, curriculum reforms, junior high school, educational districts, teaching practices

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Authors: Jingjue Bao, Ye Li, Yujie Qi

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The explosive growth of ride-hailing has reshaped residents' travel behavior and plays a crucial role in urban mobility within the built environment. Contributing to the research of the spatial variation of ride-hailing demand and its relationship to the built environment and socioeconomic factors, this study utilizes multi-source data from Haikou, China, to construct a Multi-scale Geographically Weighted Regression model (MGWR), considering spatial scale heterogeneity. The regression results showed that MGWR model was demonstrated superior interpretability and reliability with an improvement of 3.4% on R2 and from 4853 to 4787 on AIC, compared with Geographically Weighted Regression model (GWR). Furthermore, to precisely identify the surrounding environment of sampling point, DeepLabv3+ model is employed to segment street-level images. Features extracted from these images are incorporated as variables in the regression model, further enhancing its rationality and accuracy by 7.78% improvement on R2 compared with the MGWR model only considered region-level variables. By integrating multi-scale geospatial data and utilizing advanced computer vision techniques, this study provides a comprehensive understanding of the spatial dynamics between ride-hailing demand and the urban built environment. The insights gained from this research are expected to contribute significantly to urban transportation planning and policy making, as well as ride-hailing platforms, facilitating the development of more efficient and effective mobility solutions in modern cities.

Keywords: travel behavior, ride-hailing, spatial relationship, built environment, street-level image

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Authors: Burak M. Gonultas

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Criminal investigation provides a practical contribution to this process while criminology provides a theoretical background in the apprehension of criminals arrest and clarification of crimes. However, studies on criminal investigation, which is a practical aspect of this process, are not sufficient. Every crime involves different dynamics in terms of investigation. But investigations of serious crimes are versatile and contains complex processes because of cases they are conducted. Therefore, professionals who conduct serious crime investigations differ in some aspects from others in the field. The most fundamental element of this differentiation is skills and abilities of these professionals. According to Eurostat data, Turkey is in an important position in terms of homicide rates. Therefore, in Turkey practice of serious crime investigation is specialized. The present study aims to research the skills and abilities expected from professionals in conducting an effective serious criminal investigation in Turkey and so aims to offer a number of suggestions. 25 emerged ability and skills collected from literature were asked to professionals (n=289) with semi-structured form according to 5 provinces with the highest and 2 provinces with the lowest number of serious crime cases. Three data categories were collected during experience: 1- Five most important skills and abilities, 2- The most important skills for knowledge and inquiry management and 3- Ability and skills that stand out for five stages of serious criminal investigation. The most rated skills and abilities are investigative skill (13%, n=134), planning/designing (9,2%, n=95) and interpersonal relations/communication (8,8%, n=91) in 1010 skills and abilities. While the 1st and 2nd suggest elections of these professionals, the 3rd also suggests how and what type of training will be given to these professionals. This practice differs from other studies in the area in terms of separately addressing the skills and abilities expected in stages of investigation and in terms of selected methodology.

Keywords: ability, criminal investigation, criminology, homicide, serious crimes, skill, Turkey

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Authors: Ehsan Alishahi, Chuang Deng

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Commercial applications of bulk metallic glasses (BMGs) were restricted due to the sudden brittle failure mode which was the main drawback in these new class of materials. Therefore, crystalline-amorphous (C-A) composites were introduced as a toughening strategy in BMGs. In spite of numerous researches in the area of metallic C-A composites, the fundamental structure-property relation in these composites that are not exactly known yet. In this study, it is aimed to investigate the fundamental properties of crystalline-amorphous interface in a model system of Cu/CuZr by using molecular dynamics simulations. Several parameters including interface energy and mechanical properties were investigated by means of atomic models and employing Embedded Atom Method (EAM) potential function. It is found that the crystalline-amorphous interfacial energy weakly depends on the orientation of the crystalline layer, which is in stark contrast to that in a regular crystalline grain boundary. Additionally, the results showed that the interface controls the yielding of the crystalline-amorphous composites during uniaxial tension either by serving as sources for dislocation nucleation in the crystalline layer or triggering local shear transformation zones in amorphous layer. The critical resolved shear stress required to nucleate the first dislocation is also found to strongly depend on the crystalline orientation. Furthermore, it is found that the interaction between dislocations and shear localization at the crystalline-amorphous interface oriented in different directions can lead to a change in the deformation mode. For instance, while the dislocation and shear banding are aligned to each other in {0 0 1} interface plane, the misorientation angle between these failure mechanisms causing more homogeneous deformation in {1 1 0} and {1 1 1} crystalline-amorphous interfaces. These results should help clarify the failure mechanism of crystalline-amorphous composites under various loading conditions.

Keywords: crystalline-amorphous, composites, orientation, plasticity

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Authors: Kai-Wei Ji, Dung-Ying Lin

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This study investigates the impact of transportation on housing prices in regions surrounding Taiwan's science parks. As these parks evolve into crucial economic and population growth centers, they attract an increasing number of residents and workers, significantly influencing local housing markets. This demographic shift raises important questions about the role of transportation in shaping real estate values. Our research examines four major science parks in Taiwan, providing a comparative analysis of how transportation conditions and population dynamics interact to affect housing price premiums. We employ an origin-destination (OD) matrix derived from pervasive traffic data to model travel patterns and their effects on real estate values. The methodology utilizes a bi-level framework: a genetic algorithm optimizes OD demand estimation at the upper level, while a user equilibrium (UE) model simulates traffic flow at the lower level. This approach enables a nuanced exploration of how population growth impacts transportation conditions and housing price premiums. By analyzing the interplay between travel costs based on OD demand estimation and housing prices, we offer valuable insights for urban planners and policymakers. These findings are crucial for informed decision-making in rapidly developing areas, where understanding the relationship between mobility and real estate values is essential for sustainable urban development.

Keywords: demand estimation, genetic algorithm, housing price, transportation

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Authors: Amina R. Issae, Godfrey C. Katusi, Beda J. Mwang’Onde, Ladslaus L. Mnyone, Allen L. Malisa

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Background: The fluctuating composition of mosquito species over time, driven by ecological changes in specific regions, plays a pivotal role in the transmission of malaria. Grasping these dynamics is fundamental for establishing a baseline understanding and is crucial for identifying transmission patterns. This knowledge is essential in devising effective strategies for managing and controlling vector populations. Our study focused on examining the species composition and Plasmodium infection rates of malaria vectors, aiming to enhance the health and well-being of communities affected by malaria. Methods: Species composition was determined through a cross-sectional collection of mosquitoes, conducted once in the village, in four selected villages of Kilosa district, Tanzania. Mosquitoes were collected indoors and outdoors using CDC light traps. A sub-sample of all collected mosquitoes was subjected to PCR identification and assayed for Plasmodium porozoites. Results: A total of 6493 female Anophelines mosquitoes were collected, of which eight species were identified as Anopheles gambiaes.l., An. funestus group, An. coustani, An. pharoensis, An. squamosus, and An. rufipes. The abundance of the Anopheles gambiaes.s.and An. funestuss.s. varied with location and village. A total of 5 sporozoite-positive mosquitoes were found, of which 4 were An. funestuss.s. and 1 was An. gambiaes.s. Conclusions: Anopheles gambiaes.s.and An. funestuss.s. were identified as the most abundant malaria vectors, respectively. Sporozoite analysis indicated this for An. funestuss.s. contribute to most of the malaria transmission in the area. Further studies are required to assess the role of seasonal shifts in vector abundance, insecticide resistance and malaria transmission of the vectors.

Keywords: mosquito, composition, malaria, sporozoites

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Authors: Nikolai David Blaskow

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Nietzsche's scholarship in the main has never quite resolved its deeply divided, at times self-contradictory responses to what Friedrich Nietzsche might have actually meant by his notion of the 'will to power'. Yet, in the context of the current global pandemic and climate change crisis, never has there been a more urgent need to investigate and resolve that contradiction. This paper argues for the 'will to power' as being a potentially irrational-rational psychopathology, one that can properly be understood only by means of Nietzsche's agonistic insights into another psychopathology—that of ressentiment. The argument also makes a case for the contention that amor fati (Nietzsche’s positive affirmation of life) may prove to be ressentiment's cure. In addition, as an integral part of the case’s methodology, the lens defined as the Mimetic and Scapegoat theory of Rene Girard (1923-2015) is brought to bear on resolving the contradiction. Ressentiment and Mimetic Theory will prove to be key players in the investigation, in as much as they expose the reasons for a modernity in crisis. The major finding of this study is that when the explanatory power of the two theories is applied, an understanding of the dynamics of the crisis in which we find ourselves emerges. The keys to that insight will include: (1) how these two psychopathologies closely resemble the contemporary neurologically defined 'borderline conditions' and their implications for culture (2) how identity politics stifle exemplary leadership, and so create toxic cultures (3) a critical assessment of Achille Mbembe's (2019) re-working of Frantz Fanon's 'ethics of the passerby' and its resonances with Nietzsche's amor fati.

Keywords: agon, amor fati, borderline conditions, ethics of the passer by, exemplary leadership, identity politics, mimesis, ressentiment, scapegoat mechanism

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Authors: Hasna Mekkaoui Alaoui, Mariem Mekkaoui Alaoui

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In a context marked by a growing and pressing demand for online training within Moroccan universities, massive open online courses (Moocs) are undergoing constant evolution, amplified by the widespread use of digital technology and accentuated by the Coronavirus pandemic. However, despite their growing popularity and expansion, these courses are still lacking in terms of tools, enabling teachers and researchers to carry out a fine-grained analysis of the learning processes taking place within them. What's more, the circulation and sharing of knowledge within these environments is becoming increasingly important. The crucial aspect of traceability emerges here, as MOOCs record and generate traces from the most minute to the most visible. This leads us to consider traceability as a valuable approach in the field of educational research, where the trace is envisaged as a research tool in its own right. In this exploratory research project, we are looking at aspects of community knowledge sharing based on traces observed in the "Communication des organisations" Mooc. Focusing in particular on the mediating trace and its impact in identifying knowledge circulation processes in this learning space, we have mobilized the traces of video capsules as an index of knowledge circulation in the Mooc device. Our study uses a methodological approach based on thematic analysis, and although the results show that learners reproduce knowledge from different video vignettes in almost identical ways, they do not limit themselves to the knowledge provided to them. This research offers concrete perspectives for improving the dynamics of online devices, with a potentially positive impact on the quality of online university teaching.

Keywords: circulation, index, digital environments, mediation., trace

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Authors: Andy Zhang, Awnik Roy, Trevor B. Chen, Bibik Oleksandar, Subodh Adhikari, Paul S. Hsu

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The durability of a combustor in gas-turbine engines is a strong function of its component temperatures and requires good control of these temperatures. Since the temperature of combustion gases frequently exceeds the melting point of the combustion liner walls, an efficient air-cooling system with optimized flow rates of cooling air is significantly important to elongate the lifetime of liner walls. To determine the effectiveness of the air-cooling system, accurate two-dimensional (2D) surface temperature measurement of combustor liner walls is crucial for advanced engine development. Traditional diagnostic techniques for temperature measurement in this application include the rmocouples, thermal wall paints, pyrometry, and phosphors. They have shown some disadvantages, including being intrusive and affecting local flame/flow dynamics, potential flame quenching, and physical damages to instrumentation due to harsh environments inside the combustor and strong optical interference from strong combustion emission in UV-Mid IR wavelength. To overcome these drawbacks, a compact and small borescope long-wave-infrared (LWIR) sensor is developed to achieve 2D high-spatial resolution, high-fidelity thermal imaging of 2D surface temperature in gas-turbine engines, providing the desired engine component temperature distribution. The compactLWIRborescope sensor makes it feasible to promote the durability of a combustor in gas-turbine engines and, furthermore, to develop more advanced gas-turbine engines.

Keywords: borescope, engine, low-wave-infrared, sensor

Procedia PDF Downloads 134