Search results for: dynamic power transmission system studies
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 32989

Search results for: dynamic power transmission system studies

23719 Detailed Degradation-Based Model for Solid Oxide Fuel Cells Long-Term Performance

Authors: Mina Naeini, Thomas A. Adams II

Abstract:

Solid Oxide Fuel Cells (SOFCs) feature high electrical efficiency and generate substantial amounts of waste heat that make them suitable for integrated community energy systems (ICEs). By harvesting and distributing the waste heat through hot water pipelines, SOFCs can meet thermal demand of the communities. Therefore, they can replace traditional gas boilers and reduce greenhouse gas (GHG) emissions. Despite these advantages of SOFCs over competing power generation units, this technology has not been successfully commercialized in large-scale to replace traditional generators in ICEs. One reason is that SOFC performance deteriorates over long-term operation, which makes it difficult to find the proper sizing of the cells for a particular ICE system. In order to find the optimal sizing and operating conditions of SOFCs in a community, a proper knowledge of degradation mechanisms and effects of operating conditions on SOFCs long-time performance is required. The simplified SOFC models that exist in the current literature usually do not provide realistic results since they usually underestimate rate of performance drop by making too many assumptions or generalizations. In addition, some of these models have been obtained from experimental data by curve-fitting methods. Although these models are valid for the range of operating conditions in which experiments were conducted, they cannot be generalized to other conditions and so have limited use for most ICEs. In the present study, a general, detailed degradation-based model is proposed that predicts the performance of conventional SOFCs over a long period of time at different operating conditions. Conventional SOFCs are composed of Yttria Stabilized Zirconia (YSZ) as electrolyte, Ni-cermet anodes, and LaSr₁₋ₓMnₓO₃ (LSM) cathodes. The following degradation processes are considered in this model: oxidation and coarsening of nickel particles in the Ni-cermet anodes, changes in the pore radius in anode, electrolyte, and anode electrical conductivity degradation, and sulfur poisoning of the anode compartment. This model helps decision makers discover the optimal sizing and operation of the cells for a stable, efficient performance with the fewest assumptions. It is suitable for a wide variety of applications. Sulfur contamination of the anode compartment is an important cause of performance drop in cells supplied with hydrocarbon-based fuel sources. H₂S, which is often added to hydrocarbon fuels as an odorant, can diminish catalytic behavior of Ni-based anodes by lowering their electrochemical activity and hydrocarbon conversion properties. Therefore, the existing models in the literature for H₂-supplied SOFCs cannot be applied to hydrocarbon-fueled SOFCs as they only account for the electrochemical activity reduction. A regression model is developed in the current work for sulfur contamination of the SOFCs fed with hydrocarbon fuel sources. The model is developed as a function of current density and H₂S concentration in the fuel. To the best of authors' knowledge, it is the first model that accounts for impact of current density on sulfur poisoning of cells supplied with hydrocarbon-based fuels. Proposed model has wide validity over a range of parameters and is consistent across multiple studies by different independent groups. Simulations using the degradation-based model illustrated that SOFCs voltage drops significantly in the first 1500 hours of operation. After that, cells exhibit a slower degradation rate. The present analysis allowed us to discover the reason for various degradation rate values reported in literature for conventional SOFCs. In fact, the reason why literature reports very different degradation rates, is that literature is inconsistent in definition of how degradation rate is calculated. In the literature, the degradation rate has been calculated as the slope of voltage versus time plot with the unit of voltage drop percentage per 1000 hours operation. Due to the nonlinear profile of voltage over time, degradation rate magnitude depends on the magnitude of time steps selected to calculate the curve's slope. To avoid this issue, instantaneous rate of performance drop is used in the present work. According to a sensitivity analysis, the current density has the highest impact on degradation rate compared to other operating factors, while temperature and hydrogen partial pressure affect SOFCs performance less. The findings demonstrated that a cell running at lower current density performs better in long-term in terms of total average energy delivered per year, even though initially it generates less power than if it had a higher current density. This is because of the dominant and devastating impact of large current densities on the long-term performance of SOFCs, as explained by the model.

Keywords: degradation rate, long-term performance, optimal operation, solid oxide fuel cells, SOFCs

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23718 Investigation of Heavy Metals and Nitrate Level in Drinking Water and the Side Effects on Public Health in the Capital City of Iran

Authors: Iman Nazari, Behrouz Shaabani, Ali Ramouz

Abstract:

Regarding to the dramatic rise of cancer prevalence of cancers in Iran and also base on the investigations around environmental factors which causes cancer, The air and water pollution is in high level in Iran’s capital city this issue motivated us to start an investigation on concentration of heavy metals and nitrate in Tehran’s Tap water, additionally we investigated the effects of this contaminations on public health, it is clear that heavy metals and also nitrate are causes cancers directly and indirectly, we divided the city to four districts: (1) North, (2) East, (3) West, (4) South and totally collected over 30 samples from noted districts, we obvious difference in concentrations, after a study we founded the reasons of this difference, the old distribution system, non-standard sewage disposal system, travel up from contaminated rains, releasing industrial wastes waters without any pretreatment, the most important one is the old distribution system, Tehran is an old city hence distribution system is old too we know that the old water pipes were built from alloys which containing several of this harmful heavy metals, releasing of this heavy metals from pipes to the tap water is one of the most Important reasons, as the result we presented the concentrations by districts and the alternatives to decreasing the level of this contaminations.

Keywords: water quality, heavy metals, drinking water, environmental toxinology

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23717 One-Step Synthesis of Titanium Dioxide Porous Microspheres by Picosecond Pulsed Laser Welding

Authors: Huiwu Yu, Xiangyou Li, Xiaoyan Zeng

Abstract:

Porous spheres have been widely used in many fields due to their attractive features. In this work, an approach for fabricating porous spheres of nanoparticles was presented, in which the nanoparticles were welded together to form micro spheres by simply irradiating the nanoparticles in liquid medium by a picosecond laser. As an example, anatase titanium dioxide was chosen as a typical material on account of its metastability. The structure and morphologies of the products were characterised by X-ray diffraction (XRD), scanning electron microscope (SEM), Raman, and high-resolution transmission electron microscopy (HRTEM), respectively. The results showed that, anatase titanium dioxide micro spheres (2-10 μm) with macroporous (10-100 nm) were prepared from nano-anatase titanium dioxide nanoparticles (10-100 nm). The formation process of polycrystalline anatase titanium dioxide microspheres was investigated with different liquid mediums and the input laser fluences. Thus, this facile laser irradiation approach might provide a way for the fabrication of porous microspheres without phase-transition.

Keywords: titanium dioxide, porous microspheres, picosecond laser, nano-welding

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23716 BIM Application Research Based on the Main Entrance and Garden Area Project of Shanghai Disneyland

Authors: Ying Yuken, Pengfei Wang, Zhang Qilin, Xiao Ben

Abstract:

Based on the main entrance and garden area (ME&G) project of Shanghai Disneyland, this paper introduces the application of BIM technology in this kind of low-rise comprehensive building with complex facade system, electromechanical system and decoration system. BIM technology is applied to the whole process of design, construction and completion of the whole project. With the construction of BIM application framework of the whole project, the key points of BIM modeling methods of different systems and the integration and coordination of BIM models are elaborated in detail. The specific application methods of BIM technology in similar complex low-rise building projects are sorted out. Finally, the paper summarizes the benefits of BIM technology application, and puts forward some suggestions for BIM management mode and practical application of similar projects in the future.

Keywords: BIM, complex low-rise building, BIM modeling, model integration and coordination, 3D scanning

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23715 Functioning of Public Distribution System and Calories Intake in the State of Maharashtra

Authors: Balasaheb Bansode, L. Ladusingh

Abstract:

The public distribution system is an important component of food security. It is a massive welfare program undertaken by Government of India and implemented by state government since India being a federal state; for achieving multiple objectives like eliminating hunger, reduction in malnutrition and making food consumption affordable. This program reaches at the community level through the various agencies of the government. The paper focuses on the accessibility of PDS at household level and how the present policy framework results in exclusion and inclusion errors. It tries to explore the sanctioned food grain quantity received by differentiated ration cards according to income criterion at household level, and also it has highlighted on the type of corruption in food distribution that is generated by the PDS system. The data used is of secondary nature from NSSO 68 round conducted in 2012. Bivariate and multivariate techniques have been used to understand the working and consumption of food for this paper.

Keywords: calories intake, entitle food quantity, poverty aliviation through PDS, target error

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23714 Design and Implementation of a Monitoring System Using Arduino and MATLAB

Authors: Jonas P. Reges, Jessyca A. Bessa, Auzuir R. Alexandria

Abstract:

The research came up with the need of monitoring them of temperature and relative moisture in past work that enveloped the study of a greenhouse located in the Research and Extension Unit(UEPE). This research brought several unknowns that were resolved from bibliographical research. Based on the studies performed were found some monitoring methods, including the serial communication between the arduino and matlab which showed a great option due to the low cost. The project was conducted in two stages, the first, an algorithm was developed to the Arduino and Matlab, and second, the circuits were assembled and performed the monitoring tests the following variables: moisture, temperature, and distance. During testing it was possible to momentarily observe the change in the levels of monitored variables. The project showed satisfactory results, such as: real-time verification of the change of state variables, the low cost of acquisition of the prototype, possibility of easy change of programming for the execution of monitoring of other variables. Therefore, the project showed the possibility of monitoring through software and hardware that have easy programming and can be used in several areas. However, it is observed also the possibility of improving the project from a remote monitoring via Bluetooth or web server and through the control of monitored variables.

Keywords: automation, monitoring, programming, arduino, matlab

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23713 Dynamics Pattern of Land Use and Land Cover Change and Its Driving Factors Based on a Cellular Automata Markov Model: A Case Study at Ibb Governorate, Yemen

Authors: Abdulkarem Qasem Dammag, Basema Qasim Dammag, Jian Dai

Abstract:

Change in Land use and Land cover (LU/LC) has a profound impact on the area's natural, economic, and ecological development, and the search for drivers of land cover change is one of the fundamental issues of LU/LC change. The study aimed to assess the temporal and Spatio-temporal dynamics of LU/LC in the past and to predict the future using Landsat images by exploring the characteristics of different LU/LC types. Spatio-temporal patterns of LU/LC change in Ibb Governorate, Yemen, were analyzed based on RS and GIS from 1990, 2005, and 2020. A socioeconomic survey and key informant interviews were used to assess potential drivers of LU/LC. The results showed that from 1990 to 2020, the total area of vegetation land decreased by 5.3%, while the area of barren land, grassland, built-up area, and waterbody increased by 2.7%, 1.6%, 1.04%, and 0.06%, respectively. Based on socio-economic surveys and key informant interviews, natural factors had a significant and long-term impact on land change. In contrast, site construction and socio-economic factors were the main driving forces affecting land change in a short time scale. The analysis results have been linked to the CA-Markov Land Use simulation and forecasting model for the years 2035 and 2050. The simulation results revealed from the period 2020 to 2050, the trend of dynamic changes in land use, where the total area of barren land decreased by 7.0% and grassland by 0.2%, while the vegetation land, built-up area, and waterbody increased by 4.6%, 2.6%, and 0.1 %, respectively. Overall, these findings provide LULC's past and future trends and identify drivers, which can play an important role in sustainable land use planning and management by balancing and coordinating urban growth and land use and can also be used at the regional level in different levels to provide as a reference. In addition, the results provide scientific guidance to government departments and local decision-makers in future land-use planning through dynamic monitoring of LU/LC change.

Keywords: LU/LC change, CA-Markov model, driving forces, change detection, LU/LC change simulation

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23712 Self-Education, Recognition and Well-Being Insights into Qualitative-Reconstructive Educational Research on the Value of Non-formal Education in the Adolescence

Authors: Sandra Biewers Grimm

Abstract:

International studies such as Pisa have shown an increasing social inequality in the education system, which is determined in particular by social origin and migration status. This is especially the case in the Luxembourg school system, which creates challenges for many young people due to the multilingualism in the country. While the international and also the national debate on education in the immediate aftermath of the publications of the Pisa results mainly focused on the further development of school-based learning venues and formal educational processes, it initially remained largely unclear what role exactly out-of-school learning venues and non-formal and informal learning processes could play in this further development. This has changed in the meantime. Both in the political discourses and in the scientific disciplines, those voices have become louder that draw attention to the important educational function and the enormous educational potential of out-of-school learning places as a response to the crisis of the formal education system and more than this. Youth work as an actor and approach of non-formal education is particularly in demand here. Due to its principles of self-education, participation and openness, it is considered to have a special potential in supporting the acquisition of important key competencies. In this context, the study "Educational experiences in non-formal settings" at CCY takes a differentiated look behind the scenes of education-oriented youth work and describes on the basis of empirical data what and how young people learn in youth centers and which significance they attach to these educational experiences for their subjective life situation. In this sense, the aim of the study is to reconstruct the subjective educational experiences of young people in Open Youth Work as well as to explore the value that these experiences have for young people. In doing so, it enables scientifically founded conclusions about the educational potential of youth work from the user's perspective. Initially, the study focuses on defining the concept of education in the context of non-formal education and thus sets a theoretical framework for the empirical analysis. This socio-educational term of education differs from the relevant conception of education in curricular, formal education as the acquisition of knowledge. It also differs from the operationalization of education as competence, or the differentiation into cultural, social and personal or into factual, social or methodological competence, which is often used in the European context and which has long been interpreted as a "social science reading of the question of education" (XX). Now the aim is to define a "broader" concept of education that goes beyond the normative and educational policy dimensions of a "non-formal education" and includes the classical socio-educational dimensions. Furthermore, the study works with different methods of empirical social research: In addition to ethnographic observation and an online survey, group discussions were conducted with the young people. The presentation gives an insight into the context, the methodology and the results of this study.

Keywords: non-formal education, youth research, qualitative research, educational theory

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23711 In vitro and in vivo Anticancer Activity of Nanosize Zinc Oxide Composites of Doxorubicin

Authors: Emma R. Arakelova, Stepan G. Grigoryan, Flora G. Arsenyan, Nelli S. Babayan, Ruzanna M. Grigoryan, Natalia K. Sarkisyan

Abstract:

Novel nanosize zinc oxide composites of doxorubicin obtained by deposition of 180 nm thick zinc oxide film on the drug surface using DC-magnetron sputtering of a zinc target in the form of gels (PEO+Dox+ZnO and Starch+NaCMC+Dox+ZnO) were studied for drug delivery applications. The cancer specificity was revealed both in in vitro and in vivo models. The cytotoxicity of the test compounds was analyzed against human cancer (HeLa) and normal (MRC5) cell lines using MTT colorimetric cell viability assay. IC50 values were determined and compared to reveal the cancer specificity of the test samples. The mechanistic study of the most active compound was investigated using Flow cytometry analyzing of the DNA content after PI (propidium iodide) staining. Data were analyzed with Tree Star FlowJo software using cell cycle analysis Dean-Jett-Fox module. The in vivo anticancer activity estimation experiments were carried out on mice with inoculated ascitic Ehrlich’s carcinoma at intraperitoneal introduction of doxorubicin and its zinc oxide compositions. It was shown that the nanosize zinc oxide film deposition on the drug surface leads to the selective anticancer activity of composites at the cellular level with the range of selectivity index (SI) from 4 (Starch+NaCMC+Dox+ZnO) to 200 (PEO(gel)+Dox+ZnO) which is higher than that of free Dox (SI = 56). The significant increase in vivo antitumor activity (by a factor of 2-2.5) and decrease of general toxicity of zinc oxide compositions of doxorubicin in the form of the above mentioned gels compared to free doxorubicin were shown on the model of inoculated Ehrlich's ascitic carcinoma. Mechanistic studies of anticancer activity revealed the cytostatic effect based on the high level of DNA biosynthesis inhibition at considerable low concentrations of zinc oxide compositions of doxorubicin. The results of studies in vitro and in vivo behavior of PEO+Dox+ZnO and Starch+NaCMC+Dox+ZnO composites confirm the high potential of the nanosize zinc oxide composites as a vector delivery system for future application in cancer chemotherapy.

Keywords: anticancer activity, cancer specificity, doxorubicin, zinc oxide

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23710 The Modified WBS Based on LEED Rating System in Decreasing Energy Consumption and Cost of Buildings

Authors: Mehrab Gholami Zangalani, Siavash Rajabpour

Abstract:

In compliance with the Statistical Centre of Iran (SCI)’s results, construction and housing section in Iran is consuming 40% of energy, which is 5 times more than the world average consumption. By considering the climate in Iran, the solutions in terms of design, construction and exploitation of the buildings by utilizing the LEED rating system (LRS) is presented, regarding to the reasons for the high levels of energy consumption during construction and housing in Iran. As a solution, innovative Work Break Structure (WBS) in accordance with LRS and Iranian construction’s methods is unveiled in this research. Also, by amending laws pertaining to the construction in Iran, the huge amount of energy and cost can be saved. Furthermore, with a scale-up of these results to the scale of big cities such as Tehran (one of the largest metropolitan areas in the middle east) in which the license to build more than two hundred and fifty units each day is issued, the amount of energy and cost that can be saved is estimated.

Keywords: costs reduction, energy statistics, leed rating system (LRS), work brake structure (WBS)

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23709 Convergence of Sinc Methods Applied to Kuramoto-Sivashinsky Equation

Authors: Kamel Al-Khaled

Abstract:

A comparative study of the Sinc-Galerkin and Sinc-Collocation methods for solving the Kuramoto-Sivashinsky equation is given. Both approaches depend on using Sinc basis functions. Firstly, a numerical scheme using Sinc-Galerkin method is developed to approximate the solution of Kuramoto-Sivashinsky equation. Sinc approximations to both derivatives and indefinite integrals reduces the solution to an explicit system of algebraic equations. The error in the solution is shown to converge to the exact solution at an exponential. The convergence proof of the solution for the discrete system is given using fixed-point iteration. Secondly, a combination of a Crank-Nicolson formula in the time direction, with the Sinc-collocation in the space direction is presented, where the derivatives in the space variable are replaced by the necessary matrices to produce a system of algebraic equations. The methods are tested on two examples. The demonstrated results show that both of the presented methods more or less have the same accuracy.

Keywords: Sinc-Collocation, nonlinear PDEs, numerical methods, fixed-point

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23708 A Two-Stage Adaptation towards Automatic Speech Recognition System for Malay-Speaking Children

Authors: Mumtaz Begum Mustafa, Siti Salwah Salim, Feizal Dani Rahman

Abstract:

Recently, Automatic Speech Recognition (ASR) systems were used to assist children in language acquisition as it has the ability to detect human speech signal. Despite the benefits offered by the ASR system, there is a lack of ASR systems for Malay-speaking children. One of the contributing factors for this is the lack of continuous speech database for the target users. Though cross-lingual adaptation is a common solution for developing ASR systems for under-resourced language, it is not viable for children as there are very limited speech databases as a source model. In this research, we propose a two-stage adaptation for the development of ASR system for Malay-speaking children using a very limited database. The two stage adaptation comprises the cross-lingual adaptation (first stage) and cross-age adaptation. For the first stage, a well-known speech database that is phonetically rich and balanced, is adapted to the medium-sized Malay adults using supervised MLLR. The second stage adaptation uses the speech acoustic model generated from the first adaptation, and the target database is a small-sized database of the target users. We have measured the performance of the proposed technique using word error rate, and then compare them with the conventional benchmark adaptation. The two stage adaptation proposed in this research has better recognition accuracy as compared to the benchmark adaptation in recognizing children’s speech.

Keywords: Automatic Speech Recognition System, children speech, adaptation, Malay

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23707 Enhancing Seismic Performance of Ductile Moment Frames with Delayed Wire-Rope Bracing Using Middle Steel Plate

Authors: Babak Dizangian, Mohammad Reza Ghasemi, Akram Ghalandari

Abstract:

Moment frames have considerable ductility against cyclic lateral loads and displacements; however, if this feature causes the relative displacement to exceed the permissible limit, it can impose unfavorable hysteretic behavior on the frame. Therefore, adding a bracing system with the capability of preserving the capacity of high energy absorption and controlling displacements without a considerable increase in the stiffness is quite important. This paper investigates the retrofitting of a single storey steel moment frame through a delayed wire-rope bracing system using a middle steel plate. In this model, the steel plate lies where the wire ropes meet, and the model geometry is such that the cables are continuously under tension so that they can take the most advantage of the inherent potential they have in tolerating tensile stress. Using the steel plate also reduces the system stiffness considerably compared to cross bracing systems and preserves the ductile frame’s energy absorption capacity. In this research, the software models of delayed wire-rope bracing system have been studied, validated, and compared with other researchers’ laboratory test results.

Keywords: cyclic loading, delayed wire rope bracing, ductile moment frame, energy absorption, hysteresis curve

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23706 Entry, Descent and Landing System Design and Analysis of a Small Platform in Mars Environment

Authors: Daniele Calvi, Loris Franchi, Sabrina Corpino

Abstract:

Thanks to the latest Mars mission, the planetary exploration has made enormous strides over the past ten years increasing the interest of the scientific community and beyond. These missions aim to fulfill many complex operations which are of paramount importance to mission success. Among these, a special mention goes to the Entry, Descent and Landing (EDL) functions which require a dedicated system to overcome all the obstacles of these critical phases. The general objective of the system is to safely bring the spacecraft from orbital conditions to rest on the planet surface, following the designed mission profile. For this reason, this work aims to develop a simulation tool integrating the re-entry trajectory algorithm in order to support the EDL design during the preliminary phase of the mission. This tool was used on a reference unmanned mission, whose objective is finding bio-evidence and bio-hazards on Martian (sub)surface in order to support the future manned mission. Regarding the concept of operations (CONOPS) of the mission, it concerns the use of Space Penetrator Systems (SPS) that will descend on Mars surface following a ballistic fall and will penetrate the ground after the impact with the surface (around 50 and 300 cm of depth). Each SPS shall contain all the instrumentation required to sample and make the required analyses. Respecting the low-cost and low-mass requirements, as result of the tool, an Entry Descent and Impact (EDI) system based on inflatable structure has been designed. Hence, a solution could be the one chosen by Finnish Meteorological Institute in the Mars Met-Net mission, using an inflatable Thermal Protection System (TPS) called Inflatable Braking Unit (IBU) and an additional inflatable decelerator. Consequently, there are three configurations during the EDI: at altitude of 125 km the IBU is inflated at speed 5.5 km/s; at altitude of 16 km the IBU is jettisoned and an Additional Inflatable Braking Unit (AIBU) is inflated; Lastly at about 13 km, the SPS is ejected from AIBU and it impacts on the Martian surface. Since all parameters are evaluated, it is possible to confirm that the chosen EDI system and strategy verify the requirements of the mission.

Keywords: EDL, Mars, mission, SPS, TPS

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23705 An Exploratory Research on Childhood Sexual Victimization and Its Psychological Impacts

Authors: Urwah Ali

Abstract:

The aim of this study is to carry out a meta-analysis in order to establish an overall international figure and to summarize the evidence relating to the possible relationship between child sexual abuse and subsequent mental and physical health outcomes. A systematic review was conducted using the HEC Digital Library, Pub Med, PsycINFO and SAHIL databases published after 2010 containing empirical data pertaining to CSA. Out of 124 articles assessed for eligibility, 32 studies provided evidence of a relationship between sexual child maltreatment and various health outcomes for use in subsequent meta-analyses. Statistical significance associations were observed between childhood sexual victimization and psychological problems in their adulthood [odds ratio (OR) = 1.5; 95%Cl 3.07–4.43]. For most studies included for meta-analysis, the odds ratio falls above 1.00, indicating that patients having history of childhood sexual victimization were more likely to develop psychological disorders.

Keywords: abuse, sexual abuse, childhood sexual abuse, mental health

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23704 Greek Teachers' Understandings of Typical Language Development and of Language Difficulties in Primary School Children and Their Approaches to Language Teaching

Authors: Konstantina Georgali

Abstract:

The present study explores Greek teachers’ understandings of typical language development and of language difficulties. Its core aim was to highlight that teachers need to have a thorough understanding of educational linguistics, that is of how language figures in education. They should also be aware of how language should be taught so as to promote language development for all students while at the same time support the needs of children with language difficulties in an inclusive ethos. The study, thus argued that language can be a dynamic learning mechanism in the minds of all children and a powerful teaching tool in the hands of teachers and provided current research evidence to show that structural and morphological particularities of native languages- in this case, of the Greek language- can be used by teachers to enhance children’s understanding of language and simultaneously improve oral language skills for children with typical language development and for those with language difficulties. The research was based on a Sequential Exploratory Mixed Methods Design deployed in three consecutive and integrative phases. The first phase involved 18 exploratory interviews with teachers. Its findings informed the second phase involving a questionnaire survey with 119 respondents. Contradictory questionnaire results were further investigated in a third phase employing a formal testing procedure with 60 children attending Y1, Y2 and Y3 of primary school (a research group of 30 language impaired children and a comparison group of 30 children with typical language development, both identified by their class teachers). Results showed both strengths and weaknesses in teachers’ awareness of educational linguistics and of language difficulties. They also provided a different perspective of children’s language needs and of language teaching approaches that reflected current advances and conceptualizations of language problems and opened a new window on how best they can be met in an inclusive ethos. However, teachers barely used teaching approaches that could capitalize on the particularities of the Greek language to improve language skills for all students in class. Although they seemed to realize the importance of oral language skills and their knowledge base on language related issues was adequate, their practices indicated that they did not see language as a dynamic teaching and learning mechanism that can promote children’s language development and in tandem, improve academic attainment. Important educational implications arose and clear indications of the generalization of findings beyond the Greek educational context.

Keywords: educational linguistics, inclusive ethos, language difficulties, typical language development

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23703 A Comparison of Videography Tools and Techniques in African and International Contexts

Authors: Enoch Ocran

Abstract:

Film Pertinence maintains consistency in storytelling by sustaining the natural flow of action while evoking a particular feeling or emotion from the viewers with selected motion pictures. This study presents a thorough investigation of "Film Pertinence" in videography that examines its influence in Africa and around the world. This research delves into the dynamic realm of visual storytelling through film, with a specific focus on the concept of Film Pertinence (FP). The study’s primary objectives are to conduct a comparative analysis of videography tools and techniques employed in both African and international contexts, examining how they contribute to the achievement of organizational goals and the enhancement of cultural awareness. The research methodology includes a comprehensive literature review, interviews with videographers from diverse backgrounds in Africa and the international arena, and the examination of pertinent case studies. The investigation aims to elucidate the multifaceted nature of videographic practices, with particular attention to equipment choices, visual storytelling techniques, cultural sensitivity, and adaptability. This study explores the impact of cultural differences on videography choices, aiming to promote understanding between African and foreign filmmakers and create more culturally sensitive films. It also explores the role of technology in advancing videography practices, resource allocation, and the influence of globalization on local filmmaking practices. The research also contributes to film studies by analyzing videography's impact on storytelling, guiding filmmakers to create more compelling narratives. The findings can inform film education, tailoring curricula to regional needs and opportunities. The study also encourages cross-cultural collaboration in the film industry by highlighting convergence and divergence in videography practices. At its core, this study seeks to explore the implications of film pertinence as a framework for videographic practice. It scrutinizes how cultural expression, education, and storytelling transcend geographical boundaries on a global scale. By analyzing the interplay between tools, techniques, and context, the research illuminates the ways in which videographers in Africa and worldwide apply film Pertinence principles to achieve cross-cultural communication and effectively capture the objectives of their clients. One notable focus of this paper is on the techniques employed by videographers in West Africa to emphasize storytelling and participant engagement, showcasing the relevance of FP in highlighting cultural awareness in visual storytelling. Additionally, the study highlights the prevalence of film pertinence in African agricultural documentaries produced for esteemed organizations such as the Roundtable on Sustainable Palm Oil (RSPO), Proforest, World Food Program, Fidelity Bank Ghana, Instituto BVRio, Aflatoun International, and the Solidaridad Network. These documentaries serve to promote prosperity, resilience, human rights, sustainable farming practices, community respect, and environmental preservation, underlining the vital role of film in conveying these critical messages. In summary, this research offers valuable insights into the evolving landscape of videography in different contexts, emphasizing the significance of film pertinence as a unifying principle in the pursuit of effective visual storytelling and cross-cultural communication.

Keywords: film pertinence, Africa, cultural awareness, videography tools

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23702 Numerical Optimization of Cooling System Parameters for Multilayer Lithium Ion Cell and Battery Packs

Authors: Mohammad Alipour, Ekin Esen, Riza Kizilel

Abstract:

Lithium-ion batteries are a commonly used type of rechargeable batteries because of their high specific energy and specific power. With the growing popularity of electric vehicles and hybrid electric vehicles, increasing attentions have been paid to rechargeable Lithium-ion batteries. However, safety problems, high cost and poor performance in low ambient temperatures and high current rates, are big obstacles for commercial utilization of these batteries. By proper thermal management, most of the mentioned limitations could be eliminated. Temperature profile of the Li-ion cells has a significant role in the performance, safety, and cycle life of the battery. That is why little temperature gradient can lead to great loss in the performances of the battery packs. In recent years, numerous researchers are working on new techniques to imply a better thermal management on Li-ion batteries. Keeping the battery cells within an optimum range is the main objective of battery thermal management. Commercial Li-ion cells are composed of several electrochemical layers each consisting negative-current collector, negative electrode, separator, positive electrode, and positive current collector. However, many researchers have adopted a single-layer cell to save in computing time. Their hypothesis is that thermal conductivity of the layer elements is so high and heat transfer rate is so fast. Therefore, instead of several thin layers, they model the cell as one thick layer unit. In previous work, we showed that single-layer model is insufficient to simulate the thermal behavior and temperature nonuniformity of the high-capacity Li-ion cells. We also studied the effects of the number of layers on thermal behavior of the Li-ion batteries. In this work, first thermal and electrochemical behavior of the LiFePO₄ battery is modeled with 3D multilayer cell. The model is validated with the experimental measurements at different current rates and ambient temperatures. Real time heat generation rate is also studied at different discharge rates. Results showed non-uniform temperature distribution along the cell which requires thermal management system. Therefore, aluminum plates with mini-channel system were designed to control the temperature uniformity. Design parameters such as channel number and widths, inlet flow rate, and cooling fluids are optimized. As cooling fluids, water and air are compared. Pressure drop and velocity profiles inside the channels are illustrated. Both surface and internal temperature profiles of single cell and battery packs are investigated with and without cooling systems. Our results show that using optimized Mini-channel cooling plates effectively controls the temperature rise and uniformity of the single cells and battery packs. With increasing the inlet flow rate, cooling efficiency could be reached up to 60%.

Keywords: lithium ion battery, 3D multilayer model, mini-channel cooling plates, thermal management

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23701 Fabrication of High Energy Hybrid Capacitors from Biomass Waste-Derived Activated Carbon

Authors: Makhan Maharjan, Mani Ulaganathan, Vanchiappan Aravindan, Srinivasan Madhavi, Jing-Yuan Wang, Tuti Mariana Lim

Abstract:

There is great interest to exploit sustainable, low-cost, renewable resources as carbon precursors for energy storage applications. Research on development of energy storage devices has been growing rapidly due to mismatch in power supply and demand from renewable energy sources This paper reported the synthesis of porous activated carbon from biomass waste and evaluated its performance in supercapicators. In this work, we employed orange peel (waste material) as the starting material and synthesized activated carbon by pyrolysis of KOH impregnated orange peel char at 800 °C in argon atmosphere. The resultant orange peel-derived activated carbon (OP-AC) exhibited a high BET surface area of 1,901 m2 g-1, which is the highest surface area so far reported for the orange peel. The pore size distribution (PSD) curve exhibits the pores centered at 11.26 Å pore width, suggesting dominant microporosity. The OP-AC was studied as positive electrode in combination with different negative electrode materials, such as pre-lithiated graphite (LiC6) and Li4Ti5O12 for making different hybrid capacitors. The lithium ion capacitor (LIC) fabricated using OP-AC with pre-lithiated graphite delivered a high energy density of ~106 Wh kg–1. The energy density for OP-AC||Li4Ti5O12 capacitor was ~35 Wh kg–1. For comparison purpose, configuration of OP-AC||OP-AC capacitors were studied in both aqueous (1M H2SO4) and organic (1M LiPF6 in EC-DMC) electrolytes, which delivered the energy density of 6.6 Wh kg-1 and 16.3 Wh kg-1, respectively. The cycling retentions obtained at current density of 1 A g–1 were ~85.8, ~87.0 ~82.2 and ~58.8% after 2500 cycles for OP-AC||OP-AC (aqueous), OP-AC||OP-AC (organic), OP-AC||Li4Ti5O12 and OP-AC||LiC6 configurations, respectively. In addition, characterization studies were performed by elemental and proximate composition, thermogravimetry, field emission-scanning electron microscopy, Raman spectra, X-ray diffraction (XRD) pattern, Fourier transform-infrared, X-ray photoelectron spectroscopy (XPS) and N2 sorption isotherms. The morphological features from FE-SEM exhibited well-developed porous structures. Two typical broad peaks observed in the XRD framework of the synthesized carbon implies amorphous graphitic structure. The ratio of 0.86 for ID/IG in Raman spectra infers high degree of graphitization in the sample. The band spectra of C 1s in XPS display the well resolved peaks related to carbon atoms in various chemical environments; for instances, the characteristics binding energies appeared at ~283.83, ~284.83, ~286.13, ~288.56, and ~290.70 eV which correspond to sp2 -graphitic C, sp3 -graphitic C, C-O, C=O and π-π*, respectively. Characterization studies revealed the synthesized carbon to be promising electrode material towards the application for energy storage devices. The findings opened up the possibility of developing high energy LICs from abundant, low-cost, renewable biomass waste.

Keywords: lithium-ion capacitors, orange peel, pre-lithiated graphite, supercapacitors

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23700 Advancing Healthcare Excellence in China: Crafting a Strategic Operational Evaluation Index System for Chinese Hospital Departments amid Payment Reform Initiatives

Authors: Jing Jiang, Yuguang Gao, Yang Yu

Abstract:

Facing increasingly challenging insurance payment pressures, the Chinese healthcare system is undergoing significant transformations, akin to the implementation of DRG payment models by the United States' Medicare. Consequently, there is a pressing need for Chinese hospitals to establish optimizations in departmental operations tailored to the ongoing healthcare payment reforms. This abstract delineates the meticulous construction of a scientifically rigorous and comprehensive index system at the departmental level in China strategically aligned with the evolving landscape of healthcare payment reforms. Methodologically, it integrates key process areas and maturity assessment theories, synthesizing relevant literature and industry standards to construct a robust framework and indicator pool. Employing the Delphi method, consultations with 21 experts were conducted, revealing a collective demonstration of high enthusiasm, authority, and coordination in designing the index system. The resulting model comprises four primary indicators -technical capabilities, cost-effectiveness, operational efficiency, and disciplinary potential- supported by 14 secondary indicators and 23 tertiary indicators with varied coefficient adjustment for department types (platform or surgical). The application of this evaluation system in a Chinese hospital within the northeastern region yielded results aligning seamlessly with the actual operational scenario. In conclusion, the index system comprehensively considers the integrity and effectiveness of structural, process, and outcome indicators and stands as a comprehensive reflection of the collective expertise of the engaged experts, manifesting in a model designed to elevate the operational management of hospital departments. Its strategic alignment with healthcare payment reforms holds practical significance in guiding departmental development positioning, brand cultivation, and talent development.

Keywords: Chinese healthcare system, Delphi method, departmental management, evaluation indicators, hospital operations, weight coefficients

Procedia PDF Downloads 44
23699 Electrochemical Biosensor for Rutin Detection with Multiwall Carbon Nanotubes and Cerium Dioxide Nanoparticles

Authors: Stephen Rathinaraj Benjamin, Flavio Colmati Junior, Maria Izabel Florindo Guedes, Rosa Amalia Fireman Dutra

Abstract:

A new enzymatic electrochemical biosensor based on multiwall carbon nanotubes and cerium oxide nanoparticles for the detection of rutin has been developed. The cerium oxide nanoparticles /HRP/ multiwall carbon nanotubes/ carbon paste electrode (HRP/ CeO2/MWCNTs/CPE) was prepared by ensuing addition of MWCNTs and HRP on the CPE, followed by the mixing with cerium oxide nanoparticles. Surface physical characteristics of the modified electrode and the electrochemical properties of the composite were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), cylic voltammetry (CV), differential pulse voltammetry (DPV) and square wave voltammetry (SWV). The HRP/ CeO2/MWCNTs/CPE showed good selectivity, stability and reproducibility, which was further applied to detect rutin tablet and capsule samples with satisfactory results.

Keywords: cerium dioxide nanoparticles, horseradish peroxidase, multiwall carbon nanotubes, rutin

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23698 Implementation of 4-Bit Direct Charge Transfer Switched Capacitor DAC with Mismatch Shaping Technique

Authors: Anuja Askhedkar, G. H. Agrawal, Madhu Gudgunti

Abstract:

Direct Charge Transfer Switched Capacitor (DCT-SC) DAC is the internal DAC used in Delta-Sigma (∆∑) DAC which works on Over-Sampling concept. The Switched Capacitor DAC mainly suffers from mismatch among capacitors. Mismatch among capacitors in DAC, causes non linearity between output and input. Dynamic Element Matching (DEM) technique is used to match the capacitors. According to element selection logic there are many types. In this paper, Data Weighted Averaging (DWA) technique is used for mismatch shaping. In this paper, the 4 bit DCT-SC-DAC with DWA-DEM technique is implemented using WINSPICE simulation software in 180nm CMOS technology. DNL for DAC with DWA is ±0.03 LSB and INL is ± 0.02LSB.

Keywords: ∑-Δ DAC, DCT-SC-DAC, mismatch shaping, DWA, DEM

Procedia PDF Downloads 338
23697 Integrating Renewable Energy Forecasting Systems with HEMS and Developing It with a Bottom-Up Approach

Authors: Punit Gandhi, J. C. Brezet, Tim Gorter, Uchechi Obinna

Abstract:

This paper introduces how weather forecasting could help in more efficient energy management for smart homes with the use of Home Energy Management Systems (HEMS). The paper also focuses on educating consumers and helping them make more informed decisions while using the HEMS. A combined approach of technical and user perspective has been selected to develop a novel HEMS-product-service combination in a more comprehensive manner. The current HEMS switches on/off the energy intensive appliances based on the fluctuating electricity tariffs, but with weather forecasting, it is possible to shift the time of use of energy intensive appliances to maximum electricity production from the renewable energy system installed in the house. Also, it is possible to estimate the heating/cooling load of the house for the day ahead demand. Hence, relevant insight is gained in the expected energy production and consumption load for the next day, facilitating better (more efficient, peak shaved, cheaper, etc.) energy management practices for smart homes. In literature, on the user perspective, it has been observed that consumers lose interest in using HEMS after three to four months. Therefore, to further help in better energy management practices, the new system had to be designed in a way that consumers would sustain their interaction with the system on a structural basis. It is hypothesized that, if consumers feel more comfortable with using such system, it would lead to a prolonged usage, including more energy savings and hence financial savings. To test the hypothesis, a survey for the HEMS is conducted, to which 59 valid responses were recorded. Analysis of the survey helped in designing a system which imparts better information about the energy production and consumption to the consumers. It is also found from the survey that, consumers like a variety of options and they do not like a constant reminder of what they should do. Hence, the final system is designed to encourage consumers to make an informed decision about their energy usage with a wide variety of behavioral options available. It is envisaged that the new system will be tested in several pioneering smart energy grid projects in both the Netherlands and India, with a continued ‘design thinking’ approach, combining the technical and user perspective, as the basis for further improvements.

Keywords: weather forecasting, smart grid, renewable energy forecasting, user defined HEMS

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23696 Image Based Landing Solutions for Large Passenger Aircraft

Authors: Thierry Sammour Sawaya, Heikki Deschacht

Abstract:

In commercial aircraft operations, almost half of the accidents happen during approach or landing phases. Automatic guidance and automatic landings have proven to bring significant safety value added for this challenging landing phase. This is why Airbus and ScioTeq have decided to work together to explore the capability of image-based landing solutions as additional landing aids to further expand the possibility to perform automatic approach and landing to runways where the current guiding systems are either not fitted or not optimum. Current systems for automated landing often depend on radio signals provided by airport ground infrastructure on the airport or satellite coverage. In addition, these radio signals may not always be available with the integrity and performance required for safe automatic landing. Being independent from these radio signals would widen the operations possibilities and increase the number of automated landings. Airbus and ScioTeq are joining their expertise in the field of Computer Vision in the European Program called Clean Sky 2 Large Passenger Aircraft, in which they are leading the IMBALS (IMage BAsed Landing Solutions) project. The ultimate goal of this project is to demonstrate, develop, validate and verify a certifiable automatic landing system guiding an airplane during the approach and landing phases based on an onboard camera system capturing images, enabling automatic landing independent from radio signals and without precision instrument for landing. In the frame of this project, ScioTeq is responsible for the development of the Image Processing Platform (IPP), while Airbus is responsible for defining the functional and system requirements as well as the testing and integration of the developed equipment in a Large Passenger Aircraft representative environment. The aim of this paper will be to describe the system as well as the associated methods and tools developed for validation and verification.

Keywords: aircraft landing system, aircraft safety, autoland, avionic system, computer vision, image processing

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23695 The Effect of Floor Impact Sound Insulation Performance Using Scrambled Thermoplastic Poly Urethane and Ethylene Vinyl Acetate

Authors: Bonsoo Koo, Seong Shin Hong, Byung Kwon Lee

Abstract:

Most of apartments in Korea have wall type structure that present poor performance regarding floor impact sound insulation. In order to minimize the transmission of floor impact sound, flooring structures are used in which an insulating material, 30 mm thickness pad of EPS or EVA, is sandwiched between a concrete slab and the finished mortar. Generally, a single-material pad used for insulation has a heavyweight impact sound level of 44~47 dB with 210 mm thickness slab. This study provides an analysis of the floor impact sound insulation performance using thermoplastic poly urethane (TPU), ethylene vinyl acetate (EVA), and expanded polystyrene (EPS) materials with buffering performance. Following mock-up tests the effect of lightweight impact sound turned out to be similar but heavyweight impact sound was decreased by 3 dB compared to conventional single material insulation pad.

Keywords: floor impact sound, thermoplastic poly urethane, ethylene vinyl acetate, heavyweight impact sound

Procedia PDF Downloads 386
23694 Multithreading/Multiprocessing Simulation of The International Space Station Multibody System Using A Divide and Conquer Dynamics Formulation with Flexible Bodies

Authors: Luong A. Nguyen, Elihu Deneke, Thomas L. Harman

Abstract:

This paper describes a multibody dynamics algorithm formulated for parallel implementation on multiprocessor computing platforms using the divide-and-conquer approach. The system of interest is a general topology of rigid and elastic articulated bodies with or without loops. The algorithm is an extension of Featherstone’s divide and conquer approach to include the flexible-body dynamics formulation. The equations of motion, configured for the International Space Station (ISS) with its robotic manipulator arm as a system of articulated flexible bodies, are implemented in separate computer processors. The performance of this divide-and-conquer algorithm implementation in multiple processors is compared with an existing method implemented on a single processor.

Keywords: multibody dynamics, multiple processors, multithreading, divide-and-conquer algorithm, computational efficiency, flexible body dynamics

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23693 Attitudes towards People with Disability and Career Interest in Disability Studies: A Study of Clinical Medical Students of a Tertiary Institution in Southeastern Nigeria

Authors: Ebele V. Okoli, Emmanuel Nwobi, Dozie Ezechukwu, Ijeoma Itanyi

Abstract:

One in seven people worldwide suffer from a disability. 80% of people with disabilities live in developing countries. Negative attitudes and misconceptions among health-care providers constitute barri¬ers to optimal health care for people with disabilities. This underscores the relevance of a study of the attitude of Nigerian medical students towards disability and their willingness to work in the disability sector. This was a descriptive cross-sectional study conducted among 254 penultimate and final year medical students of a university in southeastern Nigeria. The mean age of the students was 24.8 ± 3.12 years. Majority of the students were male (75.2%), single (96.9%), of the Igbo tribe (86.6%), Christian (97.6%) and grew up in urban areas (68.1%). Results indicated that the medical students had a predominantly positive attitude towards people with disability as 73.8% had a positive attitude and mean attitude score was 67.03 ± 0.14 (positive attitude = 61 – 120, negative attitude = 0 - 60). Chi-square analysis did not show any significant effect of demographic and social factors on the students’ attitude towards People with Disabilities. The students were mostly willing to work in areas that address the challenges of people with disability (70.4%) but a greater proportion had never heard about Disability Studies (67.5%). About a third of the students (33.2%) would like to travel abroad to practice in the disability sector. Conclusions: The students generally had a positive attitude towards people with disability and a greater percentage were willing to work in the disability sector in their future career. About two-thirds had however, never heard about disability studies. There was some potential for brain drain among the students as a third of the population intended to practice abroad on graduation.

Keywords: attitudes, career interest, disability, medical students

Procedia PDF Downloads 345
23692 Optimization of Urea Water Solution Injector for NH3 Uniformity Improvement in Urea-SCR System

Authors: Kyoungwoo Park, Gil Dong Kim, Seong Joon Moon, Ho Kil Lee

Abstract:

The Urea-SCR is one of the most efficient technologies to reduce NOx emissions in diesel engines. In the present work, the computational prediction of internal flow and spray characteristics in the Urea-SCR system was carried out by using 3D-CFD simulation to evaluate NH3 uniformity index (NH3 UI) and its activation time according to the official New European Driving Cycle (NEDC). The number of nozzle and its diameter, two types of injection directions, and penetration length were chosen as the design variables. The optimal solutions were obtained by coupling the CFD analysis with Taguchi method. The L16 orthogonal array and small-the-better characteristics of the Taguchi method were used, and the optimal values were confirmed to be valid with 95% confidence and 5% significance level through analysis of variance (ANOVA). The results show that the optimal solutions for the NH3 UI and activation time (NH3 UI 0.22) are obtained by 0.41 and 0,125 second, respectively, and their values are improved by 85.0% and 10.7%, respectively, compared with those of the base model.

Keywords: computational fluid dynamics, NH3 uniformity index, optimization, Taguchi method, Urea-SCR system, UWS injector

Procedia PDF Downloads 250
23691 Using Classifiers to Predict Student Outcome at Higher Institute of Telecommunication

Authors: Fuad M. Alkoot

Abstract:

We aim at highlighting the benefits of classifier systems especially in supporting educational management decisions. The paper aims at using classifiers in an educational application where an outcome is predicted based on given input parameters that represent various conditions at the institute. We present a classifier system that is designed using a limited training set with data for only one semester. The achieved system is able to reach at previously known outcomes accurately. It is also tested on new input parameters representing variations of input conditions to see its prediction on the possible outcome value. Given the supervised expectation of the outcome for the new input we find the system is able to predict the correct outcome. Experiments were conducted on one semester data from two departments only, Switching and Mathematics. Future work on other departments with larger training sets and wider input variations will show additional benefits of classifier systems in supporting the management decisions at an educational institute.

Keywords: machine learning, pattern recognition, classifier design, educational management, outcome estimation

Procedia PDF Downloads 264
23690 Experimental Performance of Vertical Diffusion Stills Utilizing Folded Sheets for Water Desalination

Authors: M. Mortada, A. Seleem, M. El-Morsi, M. Younan

Abstract:

The present study introduces the folding technology to be utilized for the first time in vertical diffusion stills. This work represents a model of the distillation process by utilizing chevron pattern of folded structure. An experimental setup has been constructed, to investigate the performance of the folded sheets in the vertical effect diffusion still for a specific range of operating conditions. An experimental comparison between the folded type and the flat type sheets has been carried out. The folded pattern showed a higher performance and there is an increase in the condensate to feed ratio that ranges from 20-30 % through the operating hot plate temperature that ranges through 60-90°C. In addition, a parametric analysis of the system using Design of Experiments statistical technique, has been developed using the experimental results to determine the effect of operating conditions on the system's performance and the best operating conditions of the system has been evaluated.

Keywords: chevron pattern, fold structure, solar distillation, vertical diffusion still

Procedia PDF Downloads 446