Search results for: state equation
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 9103

Search results for: state equation

6793 Evaluation of Quasi-Newton Strategy for Algorithmic Acceleration

Authors: T. Martini, J. M. Martínez

Abstract:

An algorithmic acceleration strategy based on quasi-Newton (or secant) methods is displayed for address the practical problem of accelerating the convergence of the Newton-Lagrange method in the case of convergence to critical multipliers. Since the Newton-Lagrange iteration converges locally at a linear rate, it is natural to conjecture that quasi-Newton methods based on the so called secant equation and some minimal variation principle, could converge superlinearly, thus restoring the convergence properties of Newton's method. This strategy can also be applied to accelerate the convergence of algorithms applied to fixed-points problems. Computational experience is reported illustrating the efficiency of this strategy to solve fixed-point problems with linear convergence rate.

Keywords: algorithmic acceleration, fixed-point problems, nonlinear programming, quasi-newton method

Procedia PDF Downloads 485
6792 Accessibility of Youth-Friendly Sexual and Reproductive Health Services to Secondary School Adolescents in Southern Cross River, Nigeria

Authors: Rosemary I. Eneji, Stephen Adi Odey, Edem Carole, Eucharia Nwagbara

Abstract:

Sexual and reproductive health behaviors are the main causes of death, disability, and disease among adolescents in Nigeria. In this study, we determined the accessibility of youth-friendly sexual and reproductive health services to secondary school adolescents in southern Cross River state, Nigeria. Nineteen randomly selected public secondary schools across the seven local government areas in the zone were used. The respondents were four hundred senior secondary (classes SSI - SS3) students aged 15-19 years, comprising 63.7% females and 36.3% males. A 50-item structured questionnaire was used for the study. There was a strong influence of age and sex of adolescents, income and occupation of parents, knowledge and awareness of adolescents, and tradition on the accessibility and use of youth-friendly sexual and reproductive health services (YFSRHS) to the adolescents. The attitude of health workers towards accessibility was of little effect. Overall, youth-friendly sexual and reproductive health services were not easily accessible to adolescents in the study area. Thus, there is need to enforce adolescent reproductive health policies in the area. Training and use of trained caregivers and peer educators to attend to adolescents and the inclusion of adolescent reproductive health as a subject in the curriculum are strongly recommended.

Keywords: youth, reproductive health, cross river state, secondary schools, Nigeria

Procedia PDF Downloads 68
6791 Disability Prevalence and Health among 60+ Population in India

Authors: Surendra Kumar Patel

Abstract:

Disability is not just a health problem; it is a complex phenomenon, reflecting the interaction between features of a person’s age and physiology. Population ageing is a major demographic issue for India in the 21st century. Older population of India constituted 8% of total population, while 5.19% has affected by disability of older age group. Objective of the present research paper is to examine the state wise differential in disability among 60+ population and to access the health care of disabled population especially the 60+ disabled persons. The data sources of the present paper are census 2001 and 2011. For analyzing the state wise differentials by disability types and comparative advantage of data, rate, ratio, and percentage have been used. The Standardized Index of Diversity of Disability (SIDD) studies differential and diversity in disability. The results show that there are 5.19% persons have disability among 60+ population and sex differential not very significant, as it is 5.3 % of male and 5.05% in female in India but place of residence shows significant variation from 2001 to 2011 census. There is huge diversity in disability prevalence among 60+ in India, highest in Sikkim followed by Rajasthan, approximately, they comprise 11%, and the lowest found in Tamil Nadu as 2.53%. This huge gap in prevalence percentage shows the health care needs of highly prevailing states.

Keywords: disability, Standardized Index of Diversity of Disability (SIDD), differential and diversity in disability, 60+ population

Procedia PDF Downloads 378
6790 Study of Heat Transfer in the Absorber Plates of a Flat-Plate Solar Collector Using Dual-Phase-Lag Model

Authors: Yu-Ching Yang, Haw-Long Lee, Win-Jin Chang

Abstract:

The present work numerically analyzes the transient heat transfer in the absorber plates of a flat-plate solar collector based on the dual-phase-lag (DPL) heat conduction model. An efficient numerical scheme involving the hybrid application of the Laplace transform and control volume methods is used to solve the linear hyperbolic heat conduction equation. This work also examines the effect of different medium parameters on the behavior of heat transfer. Results show that, while the heat-flux phase lag induces thermal waves in the medium, the temperature-gradient phase lag smoothens the thermal waves by promoting non-Fourier diffusion-like conduction into the medium.

Keywords: absorber plates, dual-phase-lag, non-Fourier, solar collector

Procedia PDF Downloads 387
6789 Development of High Quality Refractory Bricks from Fireclays for Industrial Applications

Authors: David E. Esezobor, Friday I. Apeh, Harrison O. Onovo, Ademola A. Agbeleye

Abstract:

Available indigenous refractory bricks in Nigeria can only be used in the lining of furnaces for melting of cast iron operating at less than 1,400°C or in preheating furnaces due to their low refractoriness less than 1,500°C. The bricks crack and shatter on heating at 1350 to 1450°C. In this paper, a simple and adaptable technology of manufacturing high-quality refractory bricks from selected Nigerian clays for furnace linings was developed. Fireclays from Onibode, Owode-Ketu in Ogun State and Kwoi in Kaduna State were crushed, ground, and sieved into various grain sizes using standard techniques. The pulverized clays were blended with alumina in various mix ratios and indurated in the furnace at 900 – 16000C. Their chemical, microstructure and mineralogical properties were characterized using atomic absorption spectrophotometry, scanning electron microscopy and x-ray diffraction spectrometry respectively. The mineralogical and spectrochemical analyses suggested that the clays are of siliceous alumino-silicate and acidic in nature. The appropriate blending of fireclays with alumina provided the tremendous improvement in the refractoriness of the bricks and other acceptable service properties comparable with imported refractory bricks. The change in microstructure from pseudo-hexagonal grains to equiaxed grains of well – ordered sequence of structural layers could be responsible for the improved properties.

Keywords: alumina, furnace, industry, manufacturing, refractoriness

Procedia PDF Downloads 249
6788 Modeling Intention to Use 3PL Services: An Application of the Theory of Planned Behavior

Authors: Nasrin Akter, Prem Chhetri, Shams Rahman

Abstract:

The present study tested Ajzen’s Theory of Planned Behavior (TPB) model to explain the formation of business customers’ intention to use 3PL services in Bangladesh. The findings show that the TPB model has a good fit to the data. Based on theoretical support and suggested modification indices, a refined TPB model was developed afterwards which provides a better predictive power for intention. Consistent with the theory, the results of a structural equation analysis revealed that the intention to use 3PL services is predicted by attitude and subjective norms but not by perceived behavioral control. Further investigation indicated that the paths between (attitude and intention) and (subjective norms and intention) did not statistically differ between 3PL user and non-user. Findings of this research provide an evidence base to formulate business strategies to increase the use of 3PL services in Bangladesh to enhance productivity and to gain economic efficiency.

Keywords: Bangladesh, intention, third-party logistics, Theory of Planned Behavior

Procedia PDF Downloads 579
6787 From Cascade to Cluster School Model of Teachers’ Professional Development Training Programme: Nigerian Experience, Ondo State: A Case Study

Authors: Oloruntegbe Kunle Oke, Alake Ese Monica, Odutuyi Olubu Musili

Abstract:

This research explores the differing effectiveness of cascade and cluster models in professional development programs for educators in Ondo State, Nigeria. The cascade model emphasizes a top-down approach, where training is cascaded from expert trainers to lower levels of teachers. In contrast, the cluster model, a bottom-up approach, fosters collaborative learning among teachers within specific clusters. Through a review of the literature and empirical studies of the implementations of the former in two academic sessions followed by the cluster model in another two, the study examined their effectiveness on teacher development, productivity and students’ achievements. The study also drew a comparative analysis of the strengths and weaknesses associated with each model, considering factors such as scalability, cost-effectiveness, adaptability in various contexts, and sustainability. 2500 teachers from Ondo State Primary Schools participated in the cascade with intensive training in five zones for a week each in two academic sessions. On the other hand, 1,980 and 1,663 teachers in 52 and 34 clusters, respectively, were in the first and the following session. The programs were designed for one week of rigorous training of teachers by facilitators in the former while the latter was made up of four components: sit-in-observation, need-based assessment workshop, pre-cluster and the actual cluster meetings in addition to sensitization, and took place one day a week for ten weeks. Validated Cluster Impact Survey Instruments, CISI and Teacher’s Assessment Questionnaire (TAQ) were administered to ascertain the effectiveness of the models during and after implementation. The findings from the literature detailed specific effectiveness, strengths and limitations of each approach, especially the potential for inconsistencies and resistance to change. Findings from the data collected revealed the superiority of the cluster model. Response to TAQ equally showed content knowledge and skill update in both but were more sustained in the cluster model. Overall, the study contributes to the ongoing discourse on effective strategies for improving teacher training and enhancing student outcomes, offering practical recommendations for the development and implementation of future professional development projects.

Keywords: cascade model, cluster model, teachers’ development, productivity, students’ achievement

Procedia PDF Downloads 34
6786 Economic Analysis of Cassava Value Chain by Farmers in Ilesa West Local Government Area of Osun State

Authors: Maikasuwa Mohammed Abubakar, Okebiorun Ola, M. H. Sidi, Ala Ahmed Ladan, Ango Aabdullahi Kamba

Abstract:

The study examines the economic analysis of cassava value chain by farmers in Ilesa West Local Government Area of Osun State. Simple random sampling technique was used to collect data from 200 respondents from purposively selected wards in the L.G.A. The data collected were analyzed using budgetary analysis and value addition model. The result shows that an average total cost incurred by the input dealers was ₦9,062,127.74 while the average net profit realized was ₦1,038,102.40. Other actors such as producers, processors and marketers incurred an average total cost of ₦23,324.00, ₦130,177.00 and ₦523,755.00 per production season, respectively and the average net profit realized was ₦102,614.00 for cassava producers, ₦51,131.00 for cassava processors and ₦79,045.00 for cassava marketers during cassava production season. Further analysis shows the rate of investment for cassava input dealers was ₦0.1, for cassava producers was ₦4.4, for cassava processors were ₦0.40 and for cassava marketers was ₦0.20. This indicated that rate of return on cassava was higher in cassava production than in others corridors along the value chain of cassava. However, value added the cassava producers (₦102,536.16/season) was the highest when compared with value added by cassava processors (₦51,853.82/season) and cassava marketers (₦100,885.56/season).

Keywords: Cassava, value chain, Ilesa West, Nigeria

Procedia PDF Downloads 331
6785 Marketing–Operations Alignment: A Systematic Literature and Citation Network Analysis Review

Authors: Kedwadee Sombultawee, Sakun Boon-Itt

Abstract:

This research demonstrates a systematic literature review of 62 peer-reviewed articles published in academic journals from 2000-2016 focusing on the operation and marketing interface area. The findings show the three major clusters of recent research domains, which is a review of the alignment between operations and marketing, identification of variables that impact the company and analysis of the effect of interface. Moreover, the Main Path Analysis (MPA) is mapped to show the knowledge structure of the operation and marketing interface issue. Most of the empirical research focused on company performance and new product development then analyzed the data by the structural equation model or regression. Whereas, some scholars studied the conflict of these two functions and proposed the requirement or step for alignment. Finally, the gaps in the literature are provided for future research directions.

Keywords: operations management, marketing, interface, systematic literature review

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6784 Genetic Parameters as Indicators of Sustainability and Diversity of Schinus terebinthifolius Populations in the Riparian Area of the São Francisco River

Authors: Renata Silva-Mann, Sheila Valéria Álvares Carvalho, Robério Anastácio Ferreira, Laura Jane Gomes

Abstract:

There is growing interest in defining indicators of sustainability, which are important for monitoring the conservation of native forests, particularly in areas of permanent protection. These indicators are references for assessing the state of the forest and the status of the depredated area and its ability to maintain species populations. The aim of the present study was to select genetic parameters as indicators of sustainability for Schinus terebinthifolius Raddi. Fragments located in riparian areas between the Sergipe and Alagoas States in Brazil. This species has been exploited for traditional communities, which represent 20% of the incoming. This study was carried out using the indicators suggested by the Organization for Economic Cooperation and Development, which were identified as Driving-Pressure-State-Impact-Response (DPSIR) factors. The genetic parameters were obtained in five populations located on the shores and islands of the São Francisco River, one of the most important rivers in Brazil. The framework for Schinus conservation suggests seventeen indicators of sustainability. In accordance with genetic parameters, the populations are isolated, and these genetic parameters can be used to monitor the sustainability of those populations in riparian area with the aim of defining strategies for forest restoration.

Keywords: alleles, molecular markers, genetic diversity, biodiversity

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6783 Verification of the Supercavitation Phenomena: Investigation of the Cavity Parameters and Drag Coefficients for Different Types of Cavitator

Authors: Sezer Kefeli, Sertaç Arslan

Abstract:

Supercavitation is a pressure dependent process which gives opportunity to eliminate the wetted surface effects on the underwater vehicle due to the differences of viscosity and velocity effects between liquid (freestream) and gas phase. Cavitation process occurs depending on rapid pressure drop or temperature rising in liquid phase. In this paper, pressure based cavitation is investigated due to the fact that is encountered in the underwater world, generally. Basically, this vapor-filled pressure based cavities are unstable and harmful for any underwater vehicle because these cavities (bubbles or voids) lead to intense shock waves while collapsing. On the other hand, supercavitation is a desired and stabilized phenomena than general pressure based cavitation. Supercavitation phenomena offers the idea of minimizing form drag, and thus supercavitating vehicles are revived. When proper circumstances are set up, which are either increasing the operating speed of the underwater vehicle or decreasing the pressure difference between free stream and artificial pressure, the continuity of the supercavitation is obtainable. There are 2 types of supercavitation to obtain stable and continuous supercavitation, and these are called as natural and artificial supercavitation. In order to generate natural supercavitation, various mechanical structures are discovered, which are called as cavitators. In literature, a lot of cavitator types are studied either experimentally or numerically on a CFD platforms with intent to observe natural supercavitation since the 1900s. In this paper, firstly, experimental results are obtained, and trend lines are generated based on supercavitation parameters in terms of cavitation number (), form drag coefficientC_D, dimensionless cavity diameter (d_m/d_c), and length (L_c/d_c). After that, natural cavitation verification studies are carried out for disk and cone shape cavitators. In addition, supercavitation parameters are numerically analyzed at different operating conditions, and CFD results are fitted into trend lines of experimental results. The aims of this paper are to generate one generally accepted drag coefficient equation for disk and cone cavitators at different cavitator half angle and investigation of the supercavitation parameters with respect to cavitation number. Moreover, 165 CFD analysis are performed at different cavitation numbers on FLUENT version 21R2. Five different cavitator types are modeled on SCDM with respect tocavitator’s half angles. After that, CFD database is generated depending on numerical results, and new trend lines are generated based on supercavitation parameters. These trend lines are compared with experimental results. Finally, the generally accepted drag coefficient equation and equations of supercavitation parameters are generated.

Keywords: cavity envelope, CFD, high speed underwater vehicles, supercavitation, supercavitating flows, supercavitation parameters, drag reduction, viscous force elimination, natural cavitation verification

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6782 A Dual-Mode Infinite Horizon Predictive Control Algorithm for Load Tracking in PUSPATI TRIGA Reactor

Authors: Mohd Sabri Minhat, Nurul Adilla Mohd Subha

Abstract:

The PUSPATI TRIGA Reactor (RTP), Malaysia reached its first criticality on June 28, 1982, with power capacity 1MW thermal. The Feedback Control Algorithm (FCA) which is conventional Proportional-Integral (PI) controller, was used for present power control method to control fission process in RTP. It is important to ensure the core power always stable and follows load tracking within acceptable steady-state error and minimum settling time to reach steady-state power. At this time, the system could be considered not well-posed with power tracking performance. However, there is still potential to improve current performance by developing next generation of a novel design nuclear core power control. In this paper, the dual-mode predictions which are proposed in modelling Optimal Model Predictive Control (OMPC), is presented in a state-space model to control the core power. The model for core power control was based on mathematical models of the reactor core, OMPC, and control rods selection algorithm. The mathematical models of the reactor core were based on neutronic models, thermal hydraulic models, and reactivity models. The dual-mode prediction in OMPC for transient and terminal modes was based on the implementation of a Linear Quadratic Regulator (LQR) in designing the core power control. The combination of dual-mode prediction and Lyapunov which deal with summations in cost function over an infinite horizon is intended to eliminate some of the fundamental weaknesses related to MPC. This paper shows the behaviour of OMPC to deal with tracking, regulation problem, disturbance rejection and caters for parameter uncertainty. The comparison of both tracking and regulating performance is analysed between the conventional controller and OMPC by numerical simulations. In conclusion, the proposed OMPC has shown significant performance in load tracking and regulating core power for nuclear reactor with guarantee stabilising in the closed-loop.

Keywords: core power control, dual-mode prediction, load tracking, optimal model predictive control

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6781 Lyapunov Exponents in the Restricted Three Body Problem under the Influence of Perturbations

Authors: Ram Kishor

Abstract:

The Lyapunov characteristic exponent (LCE) is an important tool to describe behavior of a dynamical system, which measures the average rate of divergence (or convergence) of a trajectory emanating in the vicinity of initial point. To analyze the behavior of nearby trajectory emanating in the neighborhood of an equilibrium point in the restricted three-body problem under the influence of perturbations in the form of radiation pressure and oblateness, we compute LCEs of first order with the help of slandered method which is based on variational equation of the system. It is observed that trajectories are chaotic in nature due positive LCEs. Also, we analyze the effect of radiation pressure and oblateness on the LCEs. Results are applicable to study the behavior of more generalized RTBP in the presence of perturbations such as PR drag, solar wind drag etc.

Keywords: Lyapunov characteristic exponent, RTBP, radiation pressure, oblateness

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6780 JaCoText: A Pretrained Model for Java Code-Text Generation

Authors: Jessica Lopez Espejel, Mahaman Sanoussi Yahaya Alassan, Walid Dahhane, El Hassane Ettifouri

Abstract:

Pretrained transformer-based models have shown high performance in natural language generation tasks. However, a new wave of interest has surged: automatic programming language code generation. This task consists of translating natural language instructions to a source code. Despite the fact that well-known pre-trained models on language generation have achieved good performance in learning programming languages, effort is still needed in automatic code generation. In this paper, we introduce JaCoText, a model based on Transformer neural network. It aims to generate java source code from natural language text. JaCoText leverages the advantages of both natural language and code generation models. More specifically, we study some findings from state of the art and use them to (1) initialize our model from powerful pre-trained models, (2) explore additional pretraining on our java dataset, (3) lead experiments combining the unimodal and bimodal data in training, and (4) scale the input and output length during the fine-tuning of the model. Conducted experiments on CONCODE dataset show that JaCoText achieves new state-of-the-art results.

Keywords: java code generation, natural language processing, sequence-to-sequence models, transformer neural networks

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6779 Comparative Study of Various Wall Finishes in Buildings in Ondo State, Nigeria

Authors: Ayodele Oluwole Alejo

Abstract:

Wall finishes are the term to describe an application over a wall surface to provide a suitable surface. Wall finishes are smelt, touched and seen by building occupiers even colour and design affects the user psychology and the atmosphere of our building. Building users/owners seem not to recognize the function of various wall finishes in building and factors to be considered in selecting them suitable for the type and purpose of proposed buildings. Therefore, defects such as deterioration, dampness, and stain may occur when comparisons of wall finishes are not made before the selection of appropriate materials at the design stage with knowledge of the various factors that may hinder the performance or maintenance culture of proposed building of a particular location. This research work investigates and compares various wall finishes in building. Buildings in Ondo state, Nigeria were used as the target area to conduct the research works. The factors bearing on various wall finishes were analyzed to find out their individual and collective impact using suitable analytical tools. The findings revealed that paint with high percentage score was the most preferred wall finishes, whereas wall paper was ranked the least by the respondent findings, Factors considered most in the selection of wall finishes was durability with the highest ranking percentage and least was the cost. The study recommends that skilled worker should carry out operations, quality product should be used and all of wall finishes and materials should be considered before selection.

Keywords: building, construction, design, finishes, wall

Procedia PDF Downloads 134
6778 The Philippine Collegian and the Catalyst's Journalistic Presentation of the UP and PUP: A Content Analysis

Authors: Diana Mariz Catangay, Irish-Ann Montano, Frances Janine Suyat

Abstract:

As an active pedestal for student’s interaction with both issues happening inside the school and out; may it be political, societal, international, or other current events, a school paper should at least meet the standard of providing a representation of the school’s morals and values and help the institution uplift its image. The researchers seek to ascertain how the two student publications from the Philippines’ two prime state universities, the University of the Philippines’ Philippine Collegian, and the Polytechnic University of the Philippines’ the Catalyst, presents iii their school through balanced journalism and objective documentation. The objectives include determining the number of school-related articles published versus those articles that are concerned outside the school’s jurisdiction, analyzing the insight it provides on the image of the university, assessing the similarities and/or differences between the two publications, and, finally, coming up with the conclusion of how the two newspapers uses their medium to present their respective schools. The research used the quantitative method of research in order to further analyze the articles that will serve as bases in coming up with the right conclusion based on the objectives of the study. Coding sheets and coding guides are utilized for the chosen research method. The gathered findings will then be interpreted as fitting to the goal of the research.

Keywords: content analysis, journalistic presentation, student publications, state universities

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6777 Brand Extension and Customer WOM: Evidence from the Sports Industry

Authors: Jim Shih-Chiao Chin, Yu Ting Yeh, Shui Lien Chen, Yi-Fen Tsai

Abstract:

his study is taking Adidas Company as the object, explored the brand awareness directly or indirectly affects brand affect and word of mouth. First, explored the brand awareness on category fit and image fit, and examined the influence of category fit and image fit on extension attitude. This study then designates the effect of extension attitude on brand affect and word-of-mouth. The relationship of brand awareness on brand affect and word-of-mouth was also explored. The study participants are people who have purchased Adidas extension products. A total of 700 valid questionnaires were collected and statistical software AMOS 20.0 was used to examine the research hypotheses by using structural equation modeling (SEM). Finally, theoretical implications and research directions are provided for future studies.

Keywords: brand extension, brand awareness, product category fit, brand image fit, brand affect, word-of-mouth (WOM)

Procedia PDF Downloads 329
6776 Broadening the Public Sphere: Examining the Role of Community Radio in Fostering Participatory Democracy in Selected Communities in Ondo State, Nigeria

Authors: John Ibanga

Abstract:

Since May 1999, when Nigeria returned to uninterrupted democratic rule, there have been various attempts by successive governments at committing themselves to democratic ideals. Such efforts include a revision of communication policies after repeated calls by civil society organisations, development partners, researchers, and academics to allow not only the commencement of campus radio broadcasting but also the takeoff of community radio broadcasting. Thus, in 2015, operating licenses were granted to several communities spread across the six geopolitical zones in the country for the establishment of community radio stations culminating in the establishment of the first community radio in Nigeria on July 17, 2015. And, since citizens’ involvement in policy matters and governance is one of the tenets of participatory democracy, it becomes imperative to investigate how the emerging community radio sector in Nigeria is facilitating participatory democracy among Nigerians, even in the face of attempts by the present government to silence all dissenting voices. This study, therefore, examines how residents in Ondo State, Southwest Nigeria, are utilising programmes on Ejule Nen and Kakaaki community radio stations in Ondo State, Nigeria, to deepen participatory democracy. Much of the existing studies on the role of community radio in participatory democracy and citizens' engagement efforts miss out on Nigeria because of the delayed implementation of community radio policy in Nigeria being Africa’s most populous nation as well as a major player in the affairs of the African continent. While the participatory communication and communication infrastructure theories were used as framework, data were collected from in-depth interviews with staff of the community radio station and community leaders, focus group discussions with the community residents, and qualitative content analysis of programmes on the station. The residents used the community radio stations as platforms for demanding accountability from government, mobilising resources for the execution of a number of community projects, promoting credible electoral practices, and influencing the implementation of free education policy in their communities. Hence the community radio stations became the reliable and authoritative voices of residents for participating in the public sphere and, generally, the democratic process.

Keywords: community, community radio, democracy, participatory democracy

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6775 A Xenon Mass Gauging through Heat Transfer Modeling for Electric Propulsion Thrusters

Authors: A. Soria-Salinas, M.-P. Zorzano, J. Martín-Torres, J. Sánchez-García-Casarrubios, J.-L. Pérez-Díaz, A. Vakkada-Ramachandran

Abstract:

The current state-of-the-art methods of mass gauging of Electric Propulsion (EP) propellants in microgravity conditions rely on external measurements that are taken at the surface of the tank. The tanks are operated under a constant thermal duty cycle to store the propellant within a pre-defined temperature and pressure range. We demonstrate using computational fluid dynamics (CFD) simulations that the heat-transfer within the pressurized propellant generates temperature and density anisotropies. This challenges the standard mass gauging methods that rely on the use of time changing skin-temperatures and pressures. We observe that the domes of the tanks are prone to be overheated, and that a long time after the heaters of the thermal cycle are switched off, the system reaches a quasi-equilibrium state with a more uniform density. We propose a new gauging method, which we call the Improved PVT method, based on universal physics and thermodynamics principles, existing TRL-9 technology and telemetry data. This method only uses as inputs the temperature and pressure readings of sensors externally attached to the tank. These sensors can operate during the nominal thermal duty cycle. The improved PVT method shows little sensitivity to the pressure sensor drifts which are critical towards the end-of-life of the missions, as well as little sensitivity to systematic temperature errors. The retrieval method has been validated experimentally with CO2 in gas and fluid state in a chamber that operates up to 82 bar within a nominal thermal cycle of 38 °C to 42 °C. The mass gauging error is shown to be lower than 1% the mass at the beginning of life, assuming an initial tank load at 100 bar. In particular, for a pressure of about 70 bar, just below the critical pressure of CO2, the error of the mass gauging in gas phase goes down to 0.1% and for 77 bar, just above the critical point, the error of the mass gauging of the liquid phase is 0.6% of initial tank load. This gauging method improves by a factor of 8 the accuracy of the standard PVT retrievals using look-up tables with tabulated data from the National Institute of Standards and Technology.

Keywords: electric propulsion, mass gauging, propellant, PVT, xenon

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6774 Identification and Analysis of Supports Required for Teachers Moving to Remote Teaching and Learning during Disasters and Pandemics

Authors: Susan Catapano, Meredith Jones, Carol McNulty

Abstract:

Analysis of one state’s collaborative effort to support teachers, in both public and private schools, as they moved from face-to-face teaching to remote teaching during the Covid pandemic to identify lessons learned and materials put into place to support teachers and families. Surveys were created, distributed, and analyzed throughout the three months of remote teaching, documents and lesson plans were developed, and training materials were created. All data collected and materials developed were analyzed to identify supports teachers used and needed for successful remote teaching. Researchers found most teachers easily moved to online teaching; however, many families did not have access to technology, so teachers needed to develop non-technology-based access and support for remote teaching. Teachers also reported the need to prepare to teach remotely as part of their teaching training, so they were prepared in the future. Finally, data indicated teachers were able to establish stronger relationships with families than usual as a result of remote teaching. The lessons learned and support developed are part of the state’s ongoing policy for online teaching in the event of disasters and pandemics in the future.

Keywords: remote learning, teacher education, pandemic, families

Procedia PDF Downloads 159
6773 Identifying Strategies for Improving Railway Services in Bangladesh

Authors: Armana Sabiha Huq, Tahmina Rahman Chowdhury

Abstract:

In this paper, based on the stated preference experiment, the service quality of Bangladesh Railway has been assessed, and particular importance has been given to investigate if there exists a relationship between service quality and safety. For investigation purposes, environmental and organizational factors were assumed to determine the safety performance of the railway. Data collected from the survey has been analyzed by importance-performance analysis (IPA). In this paper, a modification of the well-known importance-performance analysis (IPA) has been done by adopting the importance of the weights determined through a structural equation modeling (SEM) approach and by plotting the gap between importance and performance on a visual graph. It has been found that there exists a relationship between safety and serviceability to some extent. Limited resources are an important factor to improve the safety and serviceability condition of the BD railway. Moreover, it is observed that the limited resources available to monitor and improve the safety performance of railway.

Keywords: importance-performance analysis, GAP-IPA, SEM, serviceability, safety, factor analysis

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6772 Socio-Economic Effects of Micro-Credit on Small-Scale Poultry Farmers’ Livelihood in Ado Odo-Ota Local Government Area of Ogun State, Nigeria

Authors: E. O. Fakoya, B. G. Abiona, W. O. Oyediran, A. M. Omoare

Abstract:

This study examined the socio-economic effects of micro-credit on small scale poultry farmers’ livelihood in Ado Odo-Ota Local Government area of Ogun State. Purposive sampling method was used to select eighty (80) small scale poultry farmers that benefited in micro credit. Interview guide was used to obtain information on the respondents’ socio-economic characteristic, sources of micro-credit and the effects of micro-credit on their livelihood. The results revealed that most of the respondents (77.50 %) were males while half (40.00%) of the respondents were between the ages of 31-40 years. A high proportion (72.50%) of the respondents had formal education. The major sources of micro credit to small scale poultry farmers were cooperative society (47.50%) and personal savings (20.00%). The findings also revealed that micro-credit had positive effect on the assets and livelihoods of small scale poultry farmers’ livelihood. Results of t-test analysis showed a significant difference between the effects before and after micro-credit on small-scale poultry farmers’ Livelihood at p < 0.05. The study recommends that formal lending institution should be given necessary support by government to enable poultry farmers have access to credit facilities in the study area.

Keywords: micro-credit, effects, livelihood, poultry farmers, socio-economic, small scale

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6771 Microbiological Examination and Antimicrobial Susceptibility of Microorganisms Isolated from Salt Mining Site in Ebonyi State

Authors: Anyimc, C. J. Aneke, J. O. Orji, O. Nworie, U. C. C. Egbule

Abstract:

The microbial examination and antimicrobial susceptibility profile of microorganism isolated from the salt mining site in Ebonyi state were evaluated in the present study using a standard microbiological technique. A total of 300 samples were randomly collected in three sample groups (A, B, and C) of 100 each. Isolation, Identification and characterization of organization present on the soil samples were determined by culturing, gram-staining and biochemical technique. The result showed the following organisms were isolated with their frequency as follow: Bacillus species (37.3%) and Staphylococcus species(23.5%) had the highest frequency in the whole Sample group A and B while Klebsiella specie (15.7%), Pseudomonas species(13.7%), and Erwinia species (9.8%) had the least. Rhizopus species (42.0%) and Aspergillus species (26.0%) were the highest fungi isolated, followed by Penicillum species (20.0%) while Mucor species (4.0%), and Fusarium species (8.0%) recorded the least. Sample group C showed high microbial population of all the microbial isolates when compared to sample group A and B. Disc diffusion method was used to determine the susceptibility of isolated bacteria to various antibiotics (oxfloxacin, pefloxacin, ciprorex, augumentin, gentamycin, ciproflox, septrin, ampicillin), while agar well diffusion method was used to determine the susceptibility of isolated fungi to some antifungal drugs (metronidazole, ketoconazole, itraconazole fluconazole). The antibacterial activity of the antibiotics used showed that ciproflux has the best inhibitory effect on all the test bacteria. Ketoconazole showed the highest inhibitory effect on the fungal isolates, followed by itraconazole, while metronidazole and fluconazole showed the least inhibitory effect on the entire test fungal isolates. Hence, the multiple drug resistance of most isolates to appropriate drugs of choice are of great public health concern and cells for periodic monitoring of antibiograms to detect possible changing patterns. Microbes isolated in the salt mining site can also be used as a source of gene(s) that can increase salt tolerance in different crop species through genetic engineering.

Keywords: microorganisms, antibacterial, antifungal, resistance, salt mining site, Ebonyi State

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6770 Women Entrepreneurial Skills in Maize Processing and Value Addition in Ogun State, Nigeria

Authors: Wasiu Oyeleke Oyediran

Abstract:

Maize is a common staple food for human consumption and livestock feeds. It provides employment and means of livelihood for women in both rural areas and urban centres in Nigeria. However, the entrepreneurial skills of women engaged in its processing and value addition has not been fully enhanced. This study was therefore carried out to investigate rural women entrepreneurial skills in maize processing and value addition in Ogun State, Nigeria. Snow ball sampling technique was used in the selection of 70 respondents for this study. Data were analyzed with descriptive statistics and chi-square. Results revealed that majority (50.0%) of the respondents were 31 - 40 years of age and 60% of the respondents had spent 6 – 10 years in maize processing. The respondents have great entrepreneurial skills in popcorn (85.7%), corn cake (80.0%), corn balls (64.3%) and kokoro (52.9%) making. The majority of the respondents accessed information and entrepreneurial skills through fellow processors (88.6%) and friends and neighbours (62.9%). Major constraints to maize processing and value addition were scarcity of raw materials during off season periods (95.7%), ineffective preservation methods (88.6%), lack of modern processing equipment (82.9%), and high cost of processing machines (72.9%). Result of chi-square showed that there is significant association between personal characteristics of the respondents and entrepreneurial skills of the women at p < 0.05. It is hereby recommended that subsidized processing equipment should be made available to the maize processors in the study area by the government and NGOs.

Keywords: women, entreprenuerial skills, maize prcessing, value addition

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6769 Controlling Interactions and Non-Equilibrium Steady State in Spinning Active Matter Monolayers

Authors: Joshua Paul Steimel, Michael Pappas, Ethan Hall

Abstract:

Particle-particle interactions are critical in determining the state of an active matter system. Unique and ubiquitous non-equilibrium behavior like swarming, vortexing, spiraling, and much more is governed by interactions between active units or particles. In hybrid active-passive matter systems, the attraction between spinning active units in a 2D monolayer of passive particles is controlled by the mechanical behavior of the passive monolayer. We demonstrate here that the range and dynamics of this attraction can be controlled by changing the composition of the passive monolayer by adding dopant passive particles. These dopant passive particles effectively pin the movement of dislocation motion in the passive media and reduce the probability of defect motion required to erode the bridge of passive particles between active spinners, thus reducing the range of attraction. Additionally, by adding an out of plane component to the magnetic moment and creating a top-like motion a short range repulsion emerges between the top-like particle. At inter-top distances less than four particle diameters apart, the tops repel but beyond that, distance attract up to 13 particle diameters apart. The tops were also able to locally and transiently anneal the passive monolayer. Thus we demonstrate that by tuning several parameters of the hybrid active matter system, one can observe very different emergent behavior.

Keywords: active matter, colloids, ferromagnetic, annealing

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6768 Modeling a Sustainable City in the Twenty-First Century: A Case Study of Ibadan Oyo State Nigeria

Authors: K. J. Jegede, O. O. Odekunle

Abstract:

The challenges facing government at all levels in the area of urban development are two folds, first is how to provide basic services for urban dwellers especially the urban poor and second, how to make cities and towns as model of good places for economic development. The key ingredients and catalysts for achieving these goals are strong and virile institutional capacity, urban infrastructure and a supportive urban policy framework. The government at all levels have been upgrading and expanding city infrastructure and services in Ibadan, the state capital to support sustainable economic development of the city, particularly in the areas of electricity, neighbourhood, solid waste management, transport, water supply, education, health facilities and markets developments to discourage street trading. This paper attempts to present Ibadan in the millennium as 'a model of a sustainable city'. A planned development strategy that had sustained the growth of the city from a war camp in the 19th century to a cosmopolitan city in the 21st century with the potential to become a megacity. The presentation examines, among others, the physical structure and population density of Ibadan city, the challenges of economic development, the development of urban infrastructure and services in Ibadan metropolitan area. The paper submitted by mapping out a strategy to achieve sustainable development of Ibadan city.

Keywords: megacity, physical structure, sustainable city, urban infrastructure

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6767 Maize Farmers’ Perception of Sharp Practices among Agro-Input Dealers in Ibadan/Ibarapa Agricultural Zone, Oyo State

Authors: Ademola A. Ladele, Peace I. Aburime

Abstract:

Fake and substandard agricultural inputs pose a serious stumbling block to farm productivity and subsequently improved livelihood. There is, therefore, a need to pave ways for sustainable agriculture and self-sufficiency in food production by proffering solutions to this challenge. Maize farmers' perception of sharp practices among agro-input dealers in Ibadan/Ibarapa agricultural zone in Oyo state was therefore investigated. A multi-stage random sampling technique was used to select registered maize farmers in the Ibadan/Ibarapa agricultural zone of the Oyo State Agricultural Development Programme (OYSADEP). A structured questionnaire was used to collect information on the perception of sharp practices and the effects of sharp practices. A total of seventy-five maize farmers were interviewed. A focus group discussion was organized to identify ways of curbing sharp practices to complement the survey. Data were analyzed using descriptive statistics, Chi-square, and Pearson Product Moment Correlation (PPMC). Forms of sharp practices indicated were sales of expired fertilizers, expired pesticides, expired herbicides, underweight fertilizers, adulterated fertilizers, adulterated herbicides, packs containing broken seeds, infested seeds, lack of truth in labeling/wrong labels, manipulation of measuring scales, and false declaration of hecterages covered by tractor operators. The majority had unfavorable perception of agro-input dealers on sharp practices. A significant relationship was observed between respondents’ level of education and their perception of sharp practices. There were no significant relationships between respondents’ sex, marital status and religion, and their perception of sharp practices. A significant correlation exists between the forms of sharp practices and the perceived effect on agricultural production. It is concluded that the perceived effect of sharp practices was critical and the endemic culture of sharp practices prevailed in agro-input in Ibadan/Ibarapa agricultural zone. A standard regulatory system that will certify and monitor the quality of inputs should be put in place.

Keywords: agricultural productivity, agro-input dealers, maize farmers, sharp practices

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6766 Increase of Energy Efficiency by Means of Application of Active Bearings

Authors: Alexander Babin, Leonid Savin

Abstract:

In the present paper, increasing of energy efficiency of a thrust hybrid bearing with a central feeding chamber is considered. The mathematical model was developed to determine the pressure distribution and the reaction forces, based on the Reynolds equation and static characteristics’ equations. The boundary problem of pressure distribution calculation was solved using the method of finite differences. For various types of lubricants, geometry and operational characteristics, axial gaps can be determined, where the minimal friction coefficient is provided. The next part of the study considers the application of servovalves in order to maintain the desired position of the rotor. The report features the calculation results and the analysis of the influence of the operational and geometric parameters on the energy efficiency of mechatronic fluid-film bearings.

Keywords: active bearings, energy efficiency, mathematical model, mechatronics, thrust multipad bearing

Procedia PDF Downloads 278
6765 Using Scilab® as New Introductory Method in Numerical Calculations and Programming for Computational Fluid Dynamics (CFD)

Authors: Nicoly Coelho, Eduardo Vieira Vilas Boas, Paulo Orestes Formigoni

Abstract:

Faced with the remarkable developments in the various segments of modern engineering, provided by the increasing technological development, professionals of all educational areas need to overcome the difficulties generated due to the good understanding of those who are starting their academic journey. Aiming to overcome these difficulties, this article aims at an introduction to the basic study of numerical methods applied to fluid mechanics and thermodynamics, demonstrating the modeling and simulations with its substance, and a detailed explanation of the fundamental numerical solution for the use of finite difference method, using SCILAB, a free software easily accessible as it is free and can be used for any research center or university, anywhere, both in developed and developing countries. It is known that the Computational Fluid Dynamics (CFD) is a necessary tool for engineers and professionals who study fluid mechanics, however, the teaching of this area of knowledge in undergraduate programs faced some difficulties due to software costs and the degree of difficulty of mathematical problems involved in this way the matter is treated only in postgraduate courses. This work aims to bring the use of DFC low cost in teaching Transport Phenomena for graduation analyzing a small classic case of fundamental thermodynamics with Scilab® program. The study starts from the basic theory involving the equation the partial differential equation governing heat transfer problem, implies the need for mastery of students, discretization processes that include the basic principles of series expansion Taylor responsible for generating a system capable of convergence check equations using the concepts of Sassenfeld, finally coming to be solved by Gauss-Seidel method. In this work we demonstrated processes involving both simple problems solved manually, as well as the complex problems that required computer implementation, for which we use a small algorithm with less than 200 lines in Scilab® in heat transfer study of a heated plate in rectangular shape on four sides with different temperatures on either side, producing a two-dimensional transport with colored graphic simulation. With the spread of computer technology, numerous programs have emerged requiring great researcher programming skills. Thinking that this ability to program DFC is the main problem to be overcome, both by students and by researchers, we present in this article a hint of use of programs with less complex interface, thus enabling less difficulty in producing graphical modeling and simulation for DFC with an extension of the programming area of experience for undergraduates.

Keywords: numerical methods, finite difference method, heat transfer, Scilab

Procedia PDF Downloads 382
6764 Financial Policies in the Process of Global Crisis: Case Study Kosovo, Case Kosovo

Authors: Shpetim Rezniqi

Abstract:

Financial Policies in the process of global crisis the current crisis has swept the world with special emphasis, most developed countries, those countries which have most gross -product world and you have a high level of living.Even those who are not experts can describe the consequences of the crisis to see the reality that is seen, but how far will it go this crisis is impossible to predict. Even the biggest experts have conjecture and large divergence, but agree on one thing: - The devastating effects of this crisis will be more severe than ever before and can not be predicted.Long time, the world was dominated economic theory of free market laws. With the belief that the market is the regulator of all economic problems. The market, as river water will flow to find the best and will find the necessary solution best. Therefore much less state market barriers, less state intervention and market itself is an economic self-regulation. Free market economy became the model of global economic development and progress, it transcends national barriers and became the law of the development of the entire world economy. Globalization and global market freedom were principles of development and international cooperation. All international organizations like the World Bank, states powerful economic, development and cooperation principles laid free market economy and the elimination of state intervention. The less state intervention much more freedom of action was this market- leading international principle. We live in an era of financial tragic. Financial markets and banking in particular economies are in a state of thy good, US stock markets fell about 40%, in other words, this time, was one of the darkest moments 5 since 1920. Prior to her rank can only "collapse" of the stock of Wall Street in 1929, technological collapse of 2000, the crisis of 1973 after the Yom Kippur war, while the price of oil quadrupled and famous collapse of 1937 / '38, when Europe was beginning World war II In 2000, even though it seems like the end of the world was the corner, the world economy survived almost intact. Of course, that was small recessions in the United States, Europe, or Japan. Much more difficult the situation was at crisis 30s, or 70s, however, succeeded the world. Regarding the recent financial crisis, it has all the signs to be much sharper and with more consequences. The decline in stock prices is more a byproduct of what is really happening. Financial markets began dance of death with the credit crisis, which came as a result of the large increase in real estate prices and household debt. It is these last two phenomena can be matched very well with the gains of the '20s, a period during which people spent fists as if there was no tomorrow. All is not away from the mouth of the word recession, that fact no longer a sudden and abrupt. But as much as the financial markets melt, the greater is the risk of a problematic economy for years to come. Thus, for example, the banking crisis in Japan proved to be much more severe than initially expected, partly because the assets which were based more loans had, especially the land that falling in value. The price of land in Japan is about 15 years that continues to fall. (ADRI Nurellari-Published in the newspaper "Classifieds"). At this moment, it is still difficult to çmosh to what extent the crisis has affected the economy and what would be the consequences of the crisis. What we know is that many banks will need more time to reduce the award of credit, but banks have this primary function, this means huge loss.

Keywords: globalisation, finance, crisis, recomandation, bank, credits

Procedia PDF Downloads 388