Search results for: class dynamics
1778 Intentionality and Context in the Paradox of Reward and Punishment in the Meccan Surahs
Authors: Asmaa Fathy Mohamed Desoky
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The subject of this research is the inference of intentionality and context from the verses of the Meccan surahs, which include the paradox of reward and punishment, applied to the duality of disbelief and faith; The Holy Quran is the most important sacred linguistic reference in the Arabic language because it is rich in all the rules of the language in addition to the linguistic miracle. the Quranic text is a first-class intentional text, sent down to convey something to the recipient (Muhammad first and then communicates it to Muslims) and influence and convince him, which opens the door to many Ijtihad; a desire to reach the will of Allah and his intention from his words Almighty. Intentionality as a term is one of the most important deliberative terms, but it will be modified to suit the Quranic discourse, especially since intentionality is related to intention-as it turned out earlier - that is, it turns the reader or recipient into a predictor of the unseen, and this does not correspond to the Quranic discourse. Hence, in this research, a set of dualities will be identified that will be studied in order to clarify the meaning of them according to the opinions of previous interpreters in accordance with the sanctity of the Quranic discourse, which is intentionally related to the dualities of reward and punishment, such as: the duality of disbelief and faith, noting that it is a duality that combines opposites and Paradox on one level, because it may be an external paradox between action and reaction, and may be an internal paradox in matters related to faith, and may be a situational paradox in a specific event or a certain fact. It should be noted that the intention of the Qur'anic text is fully realized in form and content, in whole and in part, and this research includes a presentation of some applied models of the issues of intention and context that appear in the verses of the paradox of reward and punishment in the Meccan surahs in Quraan.Keywords: intentionality, context, the paradox, reward, punishment, Meccan surahs
Procedia PDF Downloads 791777 A Finite Element/Finite Volume Method for Dam-Break Flows over Deformable Beds
Authors: Alia Alghosoun, Ashraf Osman, Mohammed Seaid
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A coupled two-layer finite volume/finite element method was proposed for solving dam-break flow problem over deformable beds. The governing equations consist of the well-balanced two-layer shallow water equations for the water flow and a linear elastic model for the bed deformations. Deformations in the topography can be caused by a brutal localized force or simply by a class of sliding displacements on the bathymetry. This deformation in the bed is a source of perturbations, on the water surface generating water waves which propagate with different amplitudes and frequencies. Coupling conditions at the interface are also investigated in the current study and two mesh procedure is proposed for the transfer of information through the interface. In the present work a new procedure is implemented at the soil-water interface using the finite element and two-layer finite volume meshes with a conservative distribution of the forces at their intersections. The finite element method employs quadratic elements in an unstructured triangular mesh and the finite volume method uses the Rusanove to reconstruct the numerical fluxes. The numerical coupled method is highly efficient, accurate, well balanced, and it can handle complex geometries as well as rapidly varying flows. Numerical results are presented for several test examples of dam-break flows over deformable beds. Mesh convergence study is performed for both methods, the overall model provides new insight into the problems at minimal computational cost.Keywords: dam-break flows, deformable beds, finite element method, finite volume method, hybrid techniques, linear elasticity, shallow water equations
Procedia PDF Downloads 1811776 Survey of Free-Range inhabitants of Federal University of Agriculture Abeokuta Zoological Park
Authors: Matthew Olanrewaju Ibiyomi
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The study examined the abundance of free-range natural inhabitants of the Federal University of Agriculture, Abeokuta (FUNAAB) Zoo Park. A baseline data of free-ranging inhabitants of the Park is essential to monitor trends and institute conservation plans through unsustainable natural resources exploitation and habitat destruction. Four transects were selected across the study area. Each transect was traversed for a period of four months and observations was carried out twice a day. The Four existing tracks explored during the study were the aviary, reptile, carnivore and primate tracks. Data were analyzed using descriptive statistics. The findings from this study revealed that 8 species of natural inhabitants were identified, which were the Vervet monkey (Chlorocebuspygerythrus), Maxwell duiker(Philantombamaxwellii), Mongoose (Herpestidaespp), Bushbuck(Tragelaphusscriptus), Cobra (Najanaja), Ground squirrel (Marmotinispp), Senegal coucal(Centropus senegalensis), Black kite (Milvus migrans). The result further showed that a total of 115 animals were encountered in the primate transect, 77 animals in the carnivores transect, 46 animals in the aviary transect and 34 animals in the ungulates transect by the representative of 43.3%, 28.3%, 15.8% and 12.5% respectively. Human activities and level of disturbance were observed to have affected the abundance and distribution of animals at Funaab Zoo Park. Continuous field inventory is recommended to ascertain the dynamics of animals observed as free-range inhabitants in this study.Keywords: abundance, ecosystem, extinction, free-range
Procedia PDF Downloads 911775 Bimetallic Cu/Au Nanostructures and Bio-Application
Authors: Si Yin Tee
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Bimetallic nanostructures have received tremendous interests as a new class of nanomaterials which may have better technological usefulness with distinct properties from those of individual atoms and molecules or bulk matter. They excelled over the monometallic counterparts because of their improved electronic, optical and catalytic performances. The properties and the applicability of these bimetallic nanostructures not only depend on their size and shape, but also on the composition and their fine structure. These bimetallic nanostructures are potential candidates for bio-applications such as biosensing, bioimaging, biodiagnostics, drug delivery, targeted therapeutics, and tissue engineering. Herein, gold-incorporated copper (Cu/Au) nanostructures were synthesized through the controlled disproportionation of Cu⁺-oleylamine complex at 220 ºC to form copper nanowires and the subsequent reaction with Au³⁺ at different temperatures of 140, 220 and 300 ºC. This is to achieve their synergistic effect through the combined use of the merits of low-cost transition and high-stability noble metals. Of these Cu/Au nanostructures, Cu/Au nanotubes display the best performance towards electrochemical non-enzymatic glucose sensing, originating from the high conductivity of gold and the high aspect ratio copper nanotubes with high surface area so as to optimise the electroactive sites and facilitate mass transport. In addition to high sensitivity and fast response, the Cu/Au nanotubes possess high selectivity against interferences from other potential interfering species and excellent reproducibility with long-term stability. By introducing gold into copper nanostructures at a low level of 3, 1 and 0.1 mol% relative to initial copper precursor, a significant electrocatalytic enhancement of the resulting bimetallic Cu/Au nanostructures starts to occur at 1 mol%. Overall, the present fabrication of stable Cu/Au nanostructures offers a promising low-cost platform for sensitive, selective, reproducible and reusable electrochemical sensing of glucose.Keywords: bimetallic, electrochemical sensing, glucose oxidation, gold-incorporated copper nanostructures
Procedia PDF Downloads 5211774 Analyzing of the Urban Landscape Configurations and Expansion of Dire Dawa City, Ethiopia Using Satellite Data and Landscape Metrics Approaches
Authors: Berhanu Keno Terfa
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To realize the consequences of urbanization, accurate, and up-to-date representation of the urban landscape patterns is critical for urban planners and policymakers. Thus, the study quantitatively characterized the spatiotemporal composition and configuration of the urban landscape and urban expansion process in Dire Dawa City, Ethiopia, form the year 2006 to 2018. The integrated approaches of various sensors satellite data, Spot (2006) and Sentinel 2 (2018) combined with landscape metrics analysis was employed to explore the pattern, process, and overall growth status in the city. The result showed that the built-up area had increased by 62% between 2006 and 2018, at an average annual increment of 3.6%, while the other land covers were lost significantly due to urban expansion. The highest urban expansion has occurred in the northwest direction, whereas the most fragmented landscape pattern was recorded in the west direction. Overall, the analysis showed that Dire Dawa City experienced accelerated urban expansion with a fragmented and complicated spatiotemporal urban landscape patterns, suggesting a strong tendency towards sprawl over the past 12 years. The findings in the study could help planners and policy developers to insight the historical dynamics of the urban region for sustainable development.Keywords: zonal metrics, multi-temporal, multi-resolution, urban growth, remote sensing data
Procedia PDF Downloads 2001773 Numerical Investigation of the Bio-fouling Roughness Effect on Tidal Turbine
Authors: O. Afshar
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Unlike other renewable energy sources, tidal current energy is an extremely reliable, predictable and continuous energy source as the current pattern and speed can be predicted throughout the year. A key concern associated with tidal turbines is their long-term reliability when operating in the hostile marine environment. Bio-fouling changes the physical shape and roughness of turbine components, hence altering the overall turbine performance. This paper seeks to employ Computational Fluid Dynamics (CFD) method to quantify the effects of this problem based on the obtained flow field information. The simulation is carried out on a NACA 63-618 aerofoil. The Reynolds Averaged Navier-Stokes (RANS) equations with Shear Stress Transport (SST) turbulent model are used to simulate the flow around the model. Different levels of fouling are studied on 2D aerofoil surface with quantified fouling height and density. In terms of lift and drag coefficient results, numerical results show good agreement with the experiment which was carried out in wind tunnel. Numerical results of research indicate that an increase in fouling thickness causes an increase in drag coefficient and a reduction in lift coefficient. Moreover, pressure gradient gradually becomes adverse as height of fouling increases. In addition, result by turbulent kinetic energy contour reveals it increases with fouling height and it extends into wake due to flow separation.Keywords: tidal energy, lift coefficient, drag coefficient, roughness
Procedia PDF Downloads 3821772 Influence of Instructional Supervision on Teachers Performance in Secondary Schools in Otukpo LGA of Benue State
Authors: A. Aloga, A. S. Aloga
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The study examined the influence of instructional supervision on teachers’ performance in secondary schools in Otukpo LGA of Benue State. The study was guided by four research questions and four hypotheses. The study employed a descriptive research design. The population of the study comprised of 579 teachers in 26 public secondary schools out of which 236 respondents were sampled and used as the studied population. The instrument used for data collection was a structured questionnaire, titled ‘Instructional Supervision and Teachers Performance Questionnaire (ISTPQ)’ The data was analyzed using descriptive statistics of mean and standard deviation to answer the research questions. And Chi-Square Statistics was used to test the hypotheses at 0.05 level of significance. The study found that instructional supervision has a significant influence on teachers’ lesson planning, effective teaching, teachers’ class attendance and teachers’ classroom management. The study concluded that instructional supervision influences teachers’ performance. It was recommended that; instructional supervisors should always give useful suggestions as regards the best instructional practices needed by teachers in enhancing lesson planning. The government should recruit more trained and qualified instructional supervisors to be able to meet the intending demands of instructional supervision. This will relieve the existing few qualified instructional supervisors from work overload which may result to ineffectiveness and poor performance of their duties. Conferences and seminars should be organized for instructional supervisors from time to time to cater for the professional assistance needed by teachers. The state government should always provide adequate funding for these conferences and seminars since it provides an avenue for acquiring new knowledge in educational development by teachers among others.Keywords: influence, instructional supervision, teachers’ performance, secondary schools
Procedia PDF Downloads 1411771 Exploring Factors That May Contribute to the Underdiagnosis of Hereditary Transthyretin Amyloidosis in African American Patients
Authors: Kelsi Hagerty, Ami Rosen, Aaliyah Heyward, Nadia Ali, Emily Brown, Erin Demo, Yue Guan, Modele Ogunniyi, Brianna McDaniels, Alanna Morris, Kunal Bhatt
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Hereditary transthyretin amyloidosis (hATTR) is a progressive, multi-systemic, and life-threatening disease caused by a disruption in the TTR protein that delivers thyroxine and retinol to the liver. This disruption causes the protein to misfold into amyloid fibrils, leading to the accumulation of the amyloid fibrils in the heart, nerves, and GI tract. Over 130 variants in the TTR gene are known to cause hATTR. The Val122Ile variant is the most common in the United States and is seen almost exclusively in people of African descent. TTR variants are inherited in an autosomal dominant fashion and have incomplete penetrance and variable expressivity. Individuals with hATTR may exhibit symptoms from as early as 30 years to as late as 80 years of age. hATTR is characterized by a wide range of clinical symptoms such as cardiomyopathy, neuropathy, carpal tunnel syndrome, and GI complications. Without treatment, hATTR leads to progressive disease and can ultimately lead to heart failure. hATTR disproportionately affects individuals of African descent; the estimated prevalence of hATTR among Black individuals in the US is 3.4%. Unfortunately, hATTR is often underdiagnosed and misdiagnosed because many symptoms of the disease overlap with other cardiac conditions. Due to the progressive nature of the disease, multi-systemic manifestations that can lead to a shortened lifespan, and the availability of free genetic testing and promising FDA-approved therapies that enhance treatability, early identification of individuals with a pathogenic hATTR variant is important, as this can significantly impact medical management for patients and their relatives. Furthermore, recent literature suggests that TTR genetic testing should be performed in all patients with suspicion of TTR-related cardiomyopathy, regardless of age, and that follow-up with genetic counseling services is recommended. Relatives of patients with hATTR benefit from genetic testing because testing can identify carriers early and allow relatives to receive regular screening and management. Despite the striking prevalence of hATTR among Black individuals, hATTR remains underdiagnosed in this patient population, and germline genetic testing for hATTR in Black individuals seems to be underrepresented, though the reasons for this have not yet been brought to light. Historically, Black patients experience a number of barriers to seeking healthcare that has been hypothesized to perpetuate the underdiagnosis of hATTR, such as lack of access and mistrust of healthcare professionals. Prior research has described a myriad of factors that shape an individual’s decision about whether to pursue presymptomatic genetic testing for a familial pathogenic variant, such as family closeness and communication, family dynamics, and a desire to inform other family members about potential health risks. This study explores these factors through 10 in-depth interviews with patients with hATTR about what factors may be contributing to the underdiagnosis of hATTR in the Black population. Participants were selected from the Emory University Amyloidosis clinic based on having a molecular diagnosis of hATTR. Interviews were recorded and transcribed verbatim, then coded using MAXQDA software. Thematic analysis was completed to draw commonalities between participants. Upon preliminary analysis, several themes have emerged. Barriers identified include i) Misdiagnosis and a prolonged diagnostic odyssey, ii) Family communication and dynamics surrounding health issues, iii) Perceptions of healthcare and one’s own health risks, and iv) The need for more intimate provider-patient relationships and communication. Overall, this study gleaned valuable insight from members of the Black community about possible factors contributing to the underdiagnosis of hATTR, as well as potential solutions to go about resolving this issue.Keywords: cardiac amyloidosis, heart failure, TTR, genetic testing
Procedia PDF Downloads 981770 Consequential Investigations on the Impact of Zakat Towards the Promotion of Socio-Economic Development in Morocco: A Theoretical Framework
Authors: Mennani Maha, Attak El Houssain
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Under the massive effect of the Covid-19 health crisis, marked by a loss of competitiveness, a slowdown in growth and an accumulation of the repercussions of socio-economic inequalities, a considerable effort must be combined, in Morocco, to put into perspective macro-political, macro-economic and social opportunities. The development of a new economic and social approach is essential in order to respond to the authenticity of the new development model that will be used by the country. The appropriation of strategies of solidarity and social cohesion constitutes a participatory, competitive and inclusive approach to support the functionalities of the economic, social and political system. Therefore, the search for alternative financial resources has become a necessity to achieve the objectives of sustainable socio-economic growth on the one hand; and to promote, on the other hands, the dynamics, of large scale, social investments. The zakat remains a site of the Islamic economy dedicated to stimulating the bases of a collective adhesion of the population on the economic, as well as on the social level, thanks to a fair and equitable distribution of the zakat funds. However, Morocco is one of the few Muslim countries that has not yet had an institution for collecting and distributing this Islamic duty, which makes it difficult to measure the socio-economic impact of zakat. This theoretical document essentially ensures the development of the crucial utility of institutionalizing zakat in order to reinforce the objectives of social solidarity in Morocco in line with the process of conceptualizing a new development model.Keywords: zakat, socio-economic development, solidarity, social investment
Procedia PDF Downloads 1411769 Haiti and Power Symbolic: An Analysis Understanding of the Impact of the Presidential Political Speeches
Authors: Marc Arthur Bien Aimé, Julio da Silveira Moreira
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This study examines the political speech in Haiti over the course of the decade 2011-2021, focusing on the speeches of the presidents Michel J. Martelly and Jovenel Moïse and their impacts on their awareness collective. In using a qualitative approach, we have analyzed the speech of the president pronounced in response to the political instability of countries, as well as interviews with a group of 20 Haitians living in Port- Au-Prince. Our results put in evidence their complex relationship between politics, awareness collective, and the influence of the powers imperialists. We show that the situation in Haiti's disastrous social and political situation is driven by personal political interests and the absence of a state political project. Moreover, the speeches of the president’s analysis are meaningless, transforming concepts such as social progress and justice in simple words. This political rhetoric contributes to the domination symbolic of the population of Haitian. This study is also linked to the theme “Constitutions, processes democratic and critical of the state in Latin America,” emphasizing the importance of analysis of political speech to understand the complexities of the democratic process and criticism of the State in their Latin American region. We suggest future research to deepen our understanding of these political dynamics and their impact on public policies and developments of the constitutions throughout Latin America.Keywords: political discourse, conscience collective, inequality social, democratic processes, constitutions, Haiti
Procedia PDF Downloads 611768 Optical Board as an Artificial Technology for a Peer Teaching Class in a Nigerian University
Authors: Azidah Abu Ziden, Adu Ifedayo Emmanuel
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This study investigated the optical board as an artificial technology for peer teaching in a Nigerian university. A design and development research (DDR) design was adopted, which entailed the planning and testing of instructional design models adopted to produce the optical board. This research population involved twenty-five (25) peer-teaching students at a Nigerian university consisting of theatre arts, religion, and language education-related disciplines. Also, using a random sampling technique, this study selected eight (8) students to work on the optical board. Besides, this study introduced a research instrument titled lecturer assessment rubric containing 30-mark metrics for evaluating students’ teaching with the optical board. In this study, it was discovered that the optical board affords students acquisition of self-employment skills through their exposure to the peer teaching course, which is a teacher training module in Nigerian universities. It is evident in this study that students were able to coordinate their design and effectively develop the optical board without lecturer’s interference. This kind of achievement in this research shows that the Nigerian university curriculum had been designed with contents meant to spur students to create jobs after graduation, and effective implementation of the readily available curriculum contents is enough to imbue students with the needed entrepreneurial skills. It was recommended that the Federal Government of Nigeria (FGN) must discourage the poor implementation of Nigerian university curriculum and invest more in the betterment of the readily available curriculum instead of considering a synonymously acclaimed new curriculum for regurgitated teaching and learning process.Keywords: optical board, artificial technology, peer teaching, educational technology, Nigeria, Malaysia, university, glass, wood, electrical, improvisation
Procedia PDF Downloads 681767 Role of Inflammatory Markers in Arthritic Rats Treated with Ethanolic Bark Extract of Albizia procera
Authors: M. Sangeetha, D. Chamundeeswari, C. Saravanababu, C. Rose, V. Gopal
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Rheumatoid arthritis (RA) is a chronic, progressive, systemic inflammatory disorder affecting the synovial joints and typically producing symmetrical arthritis that leads to joint destruction, which is responsible for the deformity and disability. Despite improvements in the treatment of RA over the past decade, there still is a need for new therapeutic agents that are efficacious, less expensive, and free of severe adverse reactions. The present study aimed to investigate role of inflammatory markers in arthritic rats treated with ethanolic bark extract of Albizia procera. The protective effect of ethanolic bark extract of Albizia procera against complete Freund’s adjuvant (CFA) induced arthritis in rats. Arthritis was induced by an intradermal injection of 0.1 ml FCA in the foot pad of left hind limb of rats. ETBE (100 and 200 mg/kg b.wt./p.o) and the reference drug diclofenac (25 mg/kg b.wt./p.o) were administered to arthritic rats. Paw volume was measured for all the animals before inducing arthritis and thereafter once in seven days by using plethysmometer for 42 days. Gene expression of inflammatory markers such as IL-1β and IL-10 were investigated in paw tissues. Up regulation of IL-1β and Down regulation IL-10 were observed in CFA injected rats when compared to normal rats. ETBE attenuated these alterations dose dependently when compared to the vehicle treated rats. These results provide insights into the mechanism of anti-arthritic activity, and unravel potential therapeutic use of Albizia procera in arthritis.
Keywords: CFA-Complete Freund’s adjuvant, ETBE – ethanolic bark extract, IL- interleukins, RA-rheumatoid arthritis
Procedia PDF Downloads 2851766 Assessing the Impact of Human Behaviour on Water Resource Systems Performance: A Conceptual Framework
Authors: N. J. Shanono, J. G. Ndiritu
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The poor performance of water resource systems (WRS) has been reportedly linked to not only climate variability and the water demand dynamics but also human behaviour-driven unlawful activities. Some of these unlawful activities that have been adversely affecting water sector include unauthorized water abstractions, water wastage behaviour, refusal of water re‐use measures, excessive operational losses, discharging untreated or improperly treated wastewater, over‐application of chemicals by agricultural users and fraudulent WRS operation. Despite advances in WRS planning, operation, and analysis incorporating such undesirable human activities to quantitatively assess their impact on WRS performance remain elusive. This study was then inspired by the need to develop a methodological framework for WRS performance assessment that integrates the impact of human behaviour with WRS performance assessment analysis. We, therefore, proposed a conceptual framework for assessing the impact of human behaviour on WRS performance using the concept of socio-hydrology. The framework identifies and couples four major sources of WRS-related values (water values, water systems, water managers, and water users) using three missing links between human and water in the management of WRS (interactions, outcomes, and feedbacks). The framework is to serve as a database for choosing relevant social and hydrological variables and to understand the intrinsic relations between the selected variables to study a specific human-water problem in the context of WRS management.Keywords: conceptual framework, human behaviour; socio-hydrology; water resource systems
Procedia PDF Downloads 1351765 Contribution of Spatial Teledetection to the Geological Mapping of the Imiter Buttonhole: Application to the Mineralized Structures of the Principal Corps B3 (CPB3) of the Imiter Mine (Anti-atlas, Morocco)
Authors: Bouayachi Ali, Alikouss Saida, Baroudi Zouhir, Zerhouni Youssef, Zouhair Mohammed, El Idrissi Assia, Essalhi Mourad
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The world-class Imiter silver deposit is located on the northern flank of the Precambrian Imiter buttonhole. This deposit is formed by epithermal veins hosted in the sandstone-pelite formations of the lower complex and in the basic conglomerates of the upper complex, these veins are controlled by a regional scale fault cluster, oriented N70°E to N90°E. The present work on the contribution of remote sensing on the geological mapping of the Imiter buttonhole and application to the mineralized structures of the Principal Corps B3. Mapping on satellite images is a very important tool in mineral prospecting. It allows the localization of the zones of interest in order to orientate the field missions by helping the localization of the major structures which facilitates the interpretation, the programming and the orientation of the mining works. The predictive map also allows for the correction of field mapping work, especially the direction and dimensions of structures such as dykes, corridors or scrapings. The use of a series of processing such as SAM, PCA, MNF and unsupervised and supervised classification on a Landsat 8 satellite image of the study area allowed us to highlight the main facies of the Imite area. To improve the exploration research, we used another processing that allows to realize a spatial distribution of the alteration mineral indices, and the application of several filters on the different bands to have lineament maps.Keywords: principal corps B3, teledetection, Landsat 8, Imiter II, silver mineralization, lineaments
Procedia PDF Downloads 951764 Effect of Experience on Evacuation of Mice in Emergency Conditions
Authors: Teng Zhang, Shenshi Huang, Gang Xu, Xuelin Zhang, Shouxiang Lu
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With the acceleration of urbanization and the increasing of the population in the city, the evacuation of pedestrians suffering from disaster environments such as fire in a room or other limited space becomes a vital issue in modern society. Mice have been used in experimental crowd evacuation in recent years for its good similarities to human in physical structure and stress reaction. In this study, the effect of experience or memory on the collective behavior of mice was explored. To help mice familiarize themselves with the design of the space and the stimulus caused by smoke, we trained them repeatedly for 2 days so that they can escape from the emergency conditions as soon as possible. The escape pattern, trajectories, walking speed, turning angle and mean individual escape time of mice in each training trail were analyzed. We found that mice can build memory quickly after the first trial on the first day. On the second day, the evacuation of mice was maintained in a stable and efficient state. Meanwhile, the group with size of 30 (G30) had a shorter mean individual escape time compared with G12. Furthermore, we tested the experience of evacuation skill of mice after several days. The results showed that the mice can hold the experience or memory over 3 weeks. We proposed the importance of experience of evacuation skill and the research of training methods in experimental evacuation of mice. The results can deepen our understanding of collective behavior of mice and conduce to the establishment of animal models in the study of pedestrian crowd dynamics in emergency conditions.Keywords: experience, evacuation, mice, group size, behavior
Procedia PDF Downloads 2681763 Computational Fluid Dynamics Simulation of a Nanofluid-Based Annular Solar Collector with Different Metallic Nano-Particles
Authors: Sireetorn Kuharat, Anwar Beg
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Motivation- Solar energy constitutes the most promising renewable energy source on earth. Nanofluids are a very successful family of engineered fluids, which contain well-dispersed nanoparticles suspended in a stable base fluid. The presence of metallic nanoparticles (e.g. gold, silver, copper, aluminum etc) significantly improves the thermo-physical properties of the host fluid and generally results in a considerable boost in thermal conductivity, density, and viscosity of nanofluid compared with the original base (host) fluid. This modification in fundamental thermal properties has profound implications in influencing the convective heat transfer process in solar collectors. The potential for improving solar collector direct absorber efficiency is immense and to gain a deeper insight into the impact of different metallic nanoparticles on efficiency and temperature enhancement, in the present work, we describe recent computational fluid dynamics simulations of an annular solar collector system. The present work studies several different metallic nano-particles and compares their performance. Methodologies- A numerical study of convective heat transfer in an annular pipe solar collector system is conducted. The inner tube contains pure water and the annular region contains nanofluid. Three-dimensional steady-state incompressible laminar flow comprising water- (and other) based nanofluid containing a variety of metallic nanoparticles (copper oxide, aluminum oxide, and titanium oxide nanoparticles) is examined. The Tiwari-Das model is deployed for which thermal conductivity, specific heat capacity and viscosity of the nanofluid suspensions is evaluated as a function of solid nano-particle volume fraction. Radiative heat transfer is also incorporated using the ANSYS solar flux and Rosseland radiative models. The ANSYS FLUENT finite volume code (version 18.1) is employed to simulate the thermo-fluid characteristics via the SIMPLE algorithm. Mesh-independence tests are conducted. Validation of the simulations is also performed with a computational Harlow-Welch MAC (Marker and Cell) finite difference method and excellent correlation achieved. The influence of volume fraction on temperature, velocity, pressure contours is computed and visualized. Main findings- The best overall performance is achieved with copper oxide nanoparticles. Thermal enhancement is generally maximized when water is utilized as the base fluid, although in certain cases ethylene glycol also performs very efficiently. Increasing nanoparticle solid volume fraction elevates temperatures although the effects are less prominent in aluminum and titanium oxide nanofluids. Significant improvement in temperature distributions is achieved with copper oxide nanofluid and this is attributed to the superior thermal conductivity of copper compared to other metallic nano-particles studied. Important fluid dynamic characteristics are also visualized including circulation and temperature shoots near the upper region of the annulus. Radiative flux is observed to enhance temperatures significantly via energization of the nanofluid although again the best elevation in performance is attained consistently with copper oxide. Conclusions-The current study generalizes previous investigations by considering multiple metallic nano-particles and furthermore provides a good benchmark against which to calibrate experimental tests on a new solar collector configuration currently being designed at Salford University. Important insights into the thermal conductivity and viscosity with metallic nano-particles is also provided in detail. The analysis is also extendable to other metallic nano-particles including gold and zinc.Keywords: heat transfer, annular nanofluid solar collector, ANSYS FLUENT, metallic nanoparticles
Procedia PDF Downloads 1431762 Hydrodynamics and Heat Transfer Characteristics of a Solar Thermochemical Fluidized Bed Reactor
Authors: Selvan Bellan, Koji Matsubara, Nobuyuki Gokon, Tatsuya Kodama, Hyun Seok-Cho
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In concentrated solar thermal industry, fluidized-bed technology has been used to produce hydrogen by thermochemical two step water splitting cycles, and synthetic gas by gasification of coal coke. Recently, couple of fluidized bed reactors have been developed and tested at Niigata University, Japan, for two-step thermochemical water splitting cycles and coal coke gasification using Xe light, solar simulator. The hydrodynamic behavior of the gas-solid flow plays a vital role in the aforementioned fluidized bed reactors. Thus, in order to study the dynamics of dense gas-solid flow, a CFD-DEM model has been developed; in which the contact forces between the particles have been calculated by the spring-dashpot model, based on the soft-sphere method. Heat transfer and hydrodynamics of a solar thermochemical fluidized bed reactor filled with ceria particles have been studied numerically and experimentally for beam-down solar concentrating system. An experimental visualization of particles circulation pattern and mixing of two-tower fluidized bed system has been presented. Simulation results have been compared with experimental data to validate the CFD-DEM model. Results indicate that the model can predict the particle-fluid flow of the two-tower fluidized bed reactor. Using this model, the key operating parameters can be optimized.Keywords: solar reactor, CFD-DEM modeling, fluidized bed, beam-down solar concentrating system
Procedia PDF Downloads 1971761 Assessing the Empowerment of Muslim Women in Malawi: A Case Study of the Muslim Women Organisation
Authors: Ulemu Maseko
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This research is a critical assessment of the empowerment of Muslim women in Malawi. The study assessed, evaluated, and analyzed how the Muslim Women Organization (MWO) has influenced gender equality and women empowerment in different Islamic communities. In analyzing the data collected for this research, the study has examined the following topics: The way MWO has interpreted Islamic women’s rights, the various stereotypes Muslim women face, and lastly, the factors contributing to the limitation of Muslim women’s rights in Malawi. Towards this analysis, the study revealed that women groups such as MWO are crucial in understanding Muslim women and the different dynamics related to their empowerment. Therefore, it is necessary to understand how Muslim women comprehend various Islamic sources and how they link religion to their position and participation in society. To achieve the scope of this study, relevant works of literature that best described Islam in Malawi, Muslim women groups, and women empowerment in Malawi were used, coupled with a qualitative research approach that involved interviews, focus group discussions, and participant observations. In addition, phenomenology and feminist theoretical frameworks were used to examine and analyze the findings. Based on the findings, it can be concluded that MWO is a significant body for gender equality and women empowerment initiatives in the Malawian Islamic community. Since its establishment in 1985 till the time of this study, MWO has been an imperative driving force towards an Islamic women’s discourse that uses Islamic teachings, faith, policies, and practices to justify the role of the Muslim woman in society. This has been enlightening for their platform and has given them more confidence to justify the empowerment of Muslim women and support different initiatives towards social change.Keywords: Islam, women, empowerment, Malawi
Procedia PDF Downloads 821760 Correlations between Wear Rate and Energy Dissipation Mechanisms in a Ti6Al4V–WC/Co Sliding Pair
Authors: J. S. Rudas, J. M. Gutiérrez Cabeza, A. Corz Rodríguez, L. M. Gómez, A. O. Toro
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The prediction of the wear rate of rubbing pairs has attracted the interest of many researchers for years. It has been recently proposed that the sliding wear rate can be inferred from the calculation of the energy rate dissipated by the tribological pair. In this paper some of the dissipative mechanisms present in a pin-on-disc configuration are discussed and both analytical and numerical calculations are carried out. Three dissipative mechanisms were studied: First, the energy release due to temperature gradients within the solid; second, the heat flow from the solid to the environment, and third, the energy loss due to abrasive damage of the surface. The Finite Element Method was used to calculate the dynamics of heat transfer within the solid, with the aid of commercial software. Validation the FEM model was assisted by virtual and laboratory experimentation using different operating points (sliding velocity and geometry contact). The materials for the experiments were Ti6Al4V alloy and Tungsten Carbide (WC-Co). The results showed that the sliding wear rate has a linear relationship with the energy dissipation flow. It was also found that energy loss due to micro-cutting is relevant for the system. This mechanism changes if the sliding velocity and pin geometry are modified though the degradation coefficient continues to present a linear behavior. We found that the less relevant dissipation mechanism for all the cases studied is the energy release by temperature gradients in the solid.Keywords: degradation, dissipative mechanism, dry sliding, entropy, friction, wear
Procedia PDF Downloads 5021759 Cross-Cultural Adaptation and Validation of the Child Engagement in Daily Life in Greek
Authors: Rigas Dimakopoulos, Marianna Papadopoulou, Roser Pons
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Background: Participation in family, recreational activities and self-care is an integral part of health. It is also the main outcome of rehabilitation services for children and adolescents with motor disabilities. There are currently no tools in Greek to assess participation in young children. Purpose: To culturally adapt and validate the Greek version of the Child Engagement in Daily Living (CEDL). Method: The CEDL was cross-culturally translated into Greek using forward-backward translation, review by the expert committee, pretest application and final review. Internal consistency was evaluated using the Cronbach alpha and test-retest reliability using the intra-class correlation coefficient (ICC). Parents of children aged 18 months to 5 years and with motor disabilities were recruited. Participants completed the CEDL and the children’s gross motor function was classified using the Gross Motor Function Classification System (GMFCS). Results: Eighty-three children were included, GMFCS I-V. Mean ± standard deviation of the CEDL domains “frequency of participation” “enjoyment of participation” and “self-care” were 58.4±14.0, 3.8±1.0 and 49.9±24, respectively. Internal consistency of all domains was high; Cronbach alpha for “frequency of participation” was 0.83, for “enjoyment of participation” was 0.76 and for “self-care” was 0.92. Test-retest reliability (ICC) was excellent for the “self-care” (0.95) and good for “frequency of participation” and “enjoyment of participation” domains (0.90 and 0.88, respectively). Conclusion: The Greek CEDL has good reliability. It can be used to evaluate participation in Greek young children with motor disabilities GMFCS levels I-V.Keywords: participation, child, disabilities, child engagement in daily living
Procedia PDF Downloads 1751758 Examining Awareness, Foresight and Expectations about Fatih Project Increasing the Occasions and Normalizing the Technology Movement
Authors: Agah Tugrul Korucu, Mustafa Mucahit Gundogdu, Tarık Gencturk, Ahmet Yucel
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Countries are developing big projects and supplying financial resource for developing technological substructure and integrating technology into the education. In Turkey, the Ministry of Education, with the aim of integrating ICT into learning and teaching processes, created a project named increasing occasions and normalizing the technology movement. FATIH Project with this project, the aim is to create teaching environments which are enriched with technology. In orientating people with the technology and integrating technology into the education, teacher and teacher candidates have a big responsibility. While teachers are using technology in lesson, the devices in class and the methods developed are important factors. The aim of this research is to examine awareness, and foresight about FATIH Project in different aspects. This study was conducted during the practice period of the second semester in the 2014-2015 academic years. The working group of the research was created from 209 teacher candidates which are from different teaching departments in the Ahmet Kelesoglu Education Faculty of Necmettin Erbakan University. Scanning model was used in this research. In research, as a getting data tool evaluation of “opinion about FATIH Project: awareness, foresight and expectation scale” which was developed by Karal et. al.; personal information form which was developed by researchers were used. Cronbach coefficient which is the reliability of the scale is 0.91. In analyzing the data, statistical package program average, standard deviation, percentage, correlation, t-test and variance analysis test were used.Keywords: Fatih Project, information and communication technologies, information technology integration, views on the Fatih Project, technology integration in education
Procedia PDF Downloads 4661757 Analysis of Network Connectivity for Ship-To-Ship Maritime Communication Using IEEE 802.11 on Maritime Environment of Tanjung Perak, Indonesia
Authors: Ahmad Fauzi Makarim, Okkie Puspitorini, Hani'ah Mahmudah, Nur Adi Siswandari, Ari Wijayanti
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As a maritime country, Indonesia needs a solution in maritime connectivity which can assist the maritime communication system which including communication from harbor to the ship or ship to ship. The needs of many application services for maritime communication, whether for safety reasons until voyage service to help the process of voyage activity needs connection with a high bandwith. To support the government efforts in handling that kind of problem, a research is conducted in maritime communication issue by applying the new developed technology in Indonesia, namely IEEE 802.11. In this research, 3 outdoor WiFi devices are used in which have a frequency of 5.8 GHz. Maritime of Tanjung Perak harbor in Surabaya until Karang Jamuang Island are used as the location of the research with defining permission of ship node spreading by Navigation District Class 1. That maritime area formed by state 1 and state 2 areas which are the narrow area with average wave height of 0.7 meter based on the data from BMKG S urabaya. After that, wave height used as one of the parameters which are used in analyzing characteristic of signal propagation at sea surface, so it can be determined on the coverage area of transmitter system. In this research has been used three samples of outdoor wifi, there is the coverage of device A can be determined about 2256 meter, device B 4000 meter, and device C 1174 meter. Then to analyze of network connectivity for the ship to ship is used AODV routing algorithm system based on the value of the power transmit was smallest of all nodes within the transmitter coverage.Keywords: maritime of Indonesia, maritime communications, outdoor wifi, coverage, AODV
Procedia PDF Downloads 3511756 Distribution Pattern of Faecal Egg output and Herbage Larval Populations of Gastrointestinal Nematodes in Naturally Infected Scottish Blackface Lambs in East Scotland
Authors: M. Benothman, M. Stear, S. Mitchel, O. Abuargob, R. Vijayan, Sateesh Kumar
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Parasitic gastroenteritis caused by gastrointestinal nematodes (GIN) is a serious pathological complication in lambs. The dispersion pattern of GIN influences their transmission dynamics. There is no proper study on this aspect in Scottish Blackface lambs in Scotland. This study undertaken on 758 naturally infected, weaned, straight bred Scottish Blackface lambs in high land pasture in East Scotland extending over three months (August, September and October) in a year, and for three successive years demonstrated that the distribution of faecal egg counts (FEC) followed negative binomial distribution, with the exception of a few samples. The inverse index of dispersion (k) ranged between 0.19 ± 0.51 and 1.09 ± 0.08. Expression of low k values resulting from aggregation in a few individuals, suggested that a small proportion of animals with heavy parasitic influx significantly influenced the level of pasture contamination and parasite transmission. There was no discernible trend in the mean faecal egg count (FEC) and mean herbage larval population (HLP) in different months and in different years. Teladorsagia was the highest pasture contaminant (85.14±14.30 L3/kdh) followed by Nematodirus (53.00±13.96), Ostertagia (28.21±10.18) and Cooperia (11.43±5.55). The results of this study would be useful in instituting gastrointestinal nematode control strategies for sheep in cool temperate agro-ecological zones.Keywords: blackface lamb, faecal egg count, Gastrointestinal nematodes, herbage larval population, Scotland
Procedia PDF Downloads 4291755 Developing a Model of Teaching Writing Based On Reading Approach through Reflection Strategy for EFL Students of STKIP YPUP
Authors: Eny Syatriana, Ardiansyah
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The purpose of recent study was to develop a learning model on writing, based on the reading texts which will be read by the students using reflection strategy. The strategy would allow the students to read the text and then they would write back the main idea and to develop the text by using their own sentences. So, the writing practice was begun by reading an interesting text, then the students would develop the text which has been read into their writing. The problem questions are (1) what kind of learning model that can develop the students writing ability? (2) what is the achievement of the students of STKIP YPUP through reflection strategy? (3) is the using of the strategy effective to develop students competence In writing? (4) in what level are the students interest toward the using of a strategy In writing subject? This development research consisted of some steps, they are (1) need analysis (2) model design (3) implementation (4) model evaluation. The need analysis was applied through discussion among the writing lecturers to create a learning model for writing subject. To see the effectiveness of the model, an experiment would be delivered for one class. The instrument and learning material would be validated by the experts. In every steps of material development, there was a learning process, where would be validated by an expert. The research used development design. These Principles and procedures or research design and development .This study, researcher would do need analysis, creating prototype, content validation, and limited empiric experiment to the sample. In each steps, there should be an assessment and revision to the drafts before continue to the next steps. The second year, the prototype would be tested empirically to four classes in STKIP YPUP for English department. Implementing the test greatly was done through the action research and followed by evaluation and validation from the experts.Keywords: learning model, reflection, strategy, reading, writing, development
Procedia PDF Downloads 3651754 CFD modelling of Microdrops Manipulation by Microfluidic Oscillator
Authors: Tawfiq Chekifi, Brahim Dennai, Rachid Khelfaoui
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Over the last few decades, modeling immiscible fluids such as oil and water have been a classical research topic. Droplet-based microfluidics presents a unique platform for mixing, reaction, separation, dispersion of drops, and numerous other functions. For this purpose, several devices were studied, as well as microfluidic oscillator. The latter was obtained from wall attachment microfluidic amplifiers using a feedback loop from the outputs to the control inputs, nevertheless this device have not well used for microdrops applications. In this paper, we suggest a numerical CFD study of a microfluidic oscillator with two different lengths of feedback loop. In order to produce simultaneous microdrops of gasoil on water, a typical geometry that includes double T-junction is connected to the fluidic oscillator. The generation of microdrops is computed by volume-of-fluid method (VOF). Flow oscillations of microdrops were triggered by the Coanda effect of jet flow. The aim of work is to obtain a high oscillation frequency in output of this passive device, the influence of hydrodynamics and physics parameters on the microdrops frequency in the output of our microsystem is also analyzed, The computational results show that, the length of feedback loop, applied pressure on T-junction and interfacial tension have a significant effect on the dispersion of microdrops and its oscillation frequency. Across the range of low Reynold number, the microdrops generation and its dynamics have been accurately controlled by adjusting applying pressure ratio of two phases.Keywords: fluidic oscillator, microdrops manipulation, VOF (volume of fluid method), microfluidic oscillator
Procedia PDF Downloads 3971753 Types of School Aggression Amongst Bulgarian Students in the Age Group of 12–18 Years-Old
Authors: Yolanda Zografova, Ekaterina Dimitrova, Tsvetelina Panchelieva, Victoria Nedeva-Atanasova
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Aggression and violence amongst school-aged children are widely spread phenomenon, which is expanding both on a global level and in Bulgaria. The purpose of the paper is to reveal the overall range of different types and manifestations of school aggression in a specific age group (12 to 18 years old students) from the 5th to the 12th grade according to the Bulgarian education system. In addition, the research investigates the dynamics of aggressive behaviour in two parallel lines – a horizontal one (with students from the same age) and a vertical one (with students from different grade). In the current study based on the original authors’ inventory (School Aggression Questionnaire), the three main types of aggression are measured – physical, verbal and indirect. The sample consists of 300 students from schools in a big metropolitan city, a mid-sized town, and a small town. Results show that the predominant aggression type is the verbal one, but this is the predominant type for the girls in the sample, not for the boys. Another result is that the higher the school grade, the lower levels of overall aggression is shown by the students. The study of such a multi-dimensional phenomenon as the aggression will provide up-to-date scientific knowledge, important both for the development of science on these topics, and useful for public interests in relation to the balanced development of children and adolescents at school. The results provide an excellent base for the development of prevention and intervention programs in order to reduce school aggression.Keywords: educational psychology, School aggression, interpersonal relations, school aggression questionnaire, types of aggression
Procedia PDF Downloads 1271752 Statistical Assessment of Models for Determination of Soil–Water Characteristic Curves of Sand Soils
Authors: S. J. Matlan, M. Mukhlisin, M. R. Taha
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Characterization of the engineering behavior of unsaturated soil is dependent on the soil-water characteristic curve (SWCC), a graphical representation of the relationship between water content or degree of saturation and soil suction. A reasonable description of the SWCC is thus important for the accurate prediction of unsaturated soil parameters. The measurement procedures for determining the SWCC, however, are difficult, expensive, and time-consuming. During the past few decades, researchers have laid a major focus on developing empirical equations for predicting the SWCC, with a large number of empirical models suggested. One of the most crucial questions is how precisely existing equations can represent the SWCC. As different models have different ranges of capability, it is essential to evaluate the precision of the SWCC models used for each particular soil type for better SWCC estimation. It is expected that better estimation of SWCC would be achieved via a thorough statistical analysis of its distribution within a particular soil class. With this in view, a statistical analysis was conducted in order to evaluate the reliability of the SWCC prediction models against laboratory measurement. Optimization techniques were used to obtain the best-fit of the model parameters in four forms of SWCC equation, using laboratory data for relatively coarse-textured (i.e., sandy) soil. The four most prominent SWCCs were evaluated and computed for each sample. The result shows that the Brooks and Corey model is the most consistent in describing the SWCC for sand soil type. The Brooks and Corey model prediction also exhibit compatibility with samples ranging from low to high soil water content in which subjected to the samples that evaluated in this study.Keywords: soil-water characteristic curve (SWCC), statistical analysis, unsaturated soil, geotechnical engineering
Procedia PDF Downloads 3381751 Relative Effectiveness of Inquiry: Approach and Expository Instructional Methods in Fostering Students’ Retention in Chemistry
Authors: Joy Johnbest Egbo
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The study was designed to investigate the relative effectiveness of inquiry role approach and expository instructional methods in fostering students’ retention in chemistry. Two research questions were answered and three null hypotheses were formulated and tested at 0.05 level of significance. A quasi-experimental (the non-equivalent pretest, posttest control group) design was adopted for the study. The population for the study comprised all senior secondary school class two (SS II) students who were offering Chemistry in single sex schools in Enugu Education Zone. The instrument for data collection was a self-developed Chemistry Retention Test (CRT). Relevant data were collected from a sample of one hundred and forty–one (141) students drawn from two secondary schools (1 male and 1 female schools) using simple random sampling technique. A reliability co-efficient of 0.82 was obtained for the instrument using Kuder Richardson formular20 (K-R20). Mean and Standard deviation scores were used to answer the research questions while two–way analysis of covariance (ANCOVA) was used to test the hypotheses. The findings showed that the students taught with Inquiry role approach retained the chemistry concept significantly higher than their counterparts taught with expository method. Female students retained slightly higher than their male counterparts. There is significant interaction between instructional packages and gender on Chemistry students’ retention. It was recommended, among others, that teachers should be encouraged to employ the use of Inquiry-role approach more in the teaching of chemistry and other subjects in general. By so doing, students’ retention of the subject could be increased.Keywords: inquiry role approach, retention, exposition method, chemistry
Procedia PDF Downloads 5131750 Sib-Care and Attachment in Zambia and the Netherlands
Authors: Haatembo Mooya
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Cross-culturally, exclusive maternal care of infants is an exception, rather than a rule. In most traditional non-Western societies, child care is shared within the family while in most middle class Western societies parents tend to rely more on ‘hired hands’ for support. In both contexts however, a common caregiver is the sibling. Despite this, the phenomenon of sib-care has remained relatively understudied. Cultural and gender differences in sib-care and attachment were explored using a retrospective survey instrument comparing Zambian and Dutch college students. The total study sample (N = 394) comprised of 200 Zambian students from the University of Zambia and 194 Dutch students from Leiden University, the Netherlands. We tested four main hypotheses. Firstly, we hypothesized that the Zambian subjects performed more sib-care than Dutch subjects. Secondly we hypothesized that female participants performed more sib-care than males participants, both among the Zambian and Dutch subjects, especially when parents are not at home. Thirdly, we hypothesized that larger family size was associated with more sib-care. Finally, we hypothesized that securely attached participants performed more sib-care than their less securely attached peers. Results indicated that sib-care was prevalent in both Zambian and Dutch samples. Zambian subjects performed more sib-care than Dutch subjects, with females performing more sib-care than males, both when parents were at home (F(2, 244) = 62.09, p < .01) and when parents were not at home (F(2, 237) = 51.28, p < .01). We also found that family size and attachment related avoidance and anxiety were not significant predictors of sib-care. It is concluded that sib-care is understudied, not only in Africa but also in Western societies and that females perform more sib-care than males, especially when the parents are not at home. In addition, attachment related avoidance and anxiety appear to be more related to the quality than the quantity of sib-care provided.Keywords: sibling, sib-care, attachment, Africa, Zambia, the Netherlands
Procedia PDF Downloads 6501749 Numerical Simulation of Two-Dimensional Flow over a Stationary Circular Cylinder Using Feedback Forcing Scheme Based Immersed Boundary Finite Volume Method
Authors: Ranjith Maniyeri, Ahamed C. Saleel
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Two-dimensional fluid flow over a stationary circular cylinder is one of the bench mark problem in the field of fluid-structure interaction in computational fluid dynamics (CFD). Motivated by this, in the present work, a two-dimensional computational model is developed using an improved version of immersed boundary method which combines the feedback forcing scheme of the virtual boundary method with Peskin’s regularized delta function approach. Lagrangian coordinates are used to represent the cylinder and Eulerian coordinates are used to describe the fluid flow. A two-dimensional Dirac delta function is used to transfer the quantities between the sold to fluid domain. Further, continuity and momentum equations governing the fluid flow are solved using fractional step based finite volume method on a staggered Cartesian grid system. The developed code is validated by comparing the values of drag coefficient obtained for different Reynolds numbers with that of other researcher’s results. Also, through numerical simulations for different Reynolds numbers flow behavior is well captured. The stability analysis of the improved version of immersed boundary method is tested for different values of feedback forcing coefficients.Keywords: Feedback Forcing Scheme, Finite Volume Method, Immersed Boundary Method, Navier-Stokes Equations
Procedia PDF Downloads 305