Search results for: high temperatures
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 21093

Search results for: high temperatures

17583 A New Resonance Solution to Suppress the Voltage Stresses in the Forward Topology Used in a Switch Mode Power Supply

Authors: Maamar Latroch, Mohamed Bourahla

Abstract:

Forward topology used in switch mode power supply (SMPS) is one of the most famous configuration feeding DC systems such as telecommunication systems and other specific applications where the galvanic isolation is required. This configuration benefits of the high frequency feature of the transformer to provide a small size and light weight of the over all system. However, the stresses existing on the power switch during an ON/OFF commutation limit the transmitted power to the DC load. This paper investigates the main causes of the stresses in voltage existing during a commutation cycle and suggest a low cost solution that eliminates the overvoltage. As a result, this configuration will yield the possibility of the use of this configuration in higher power applications. Simulation results will show the efficiency of the presented method.

Keywords: switch mode power supply, forward topology, resonance topology, high frequency commutation

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17582 Contribution of PALB2 and BLM Mutations to Familial Breast Cancer Risk in BRCA1/2 Negative South African Breast Cancer Patients Detected Using High-Resolution Melting Analysis

Authors: N. C. van der Merwe, J. Oosthuizen, M. F. Makhetha, J. Adams, B. K. Dajee, S-R. Schneider

Abstract:

Women representing high-risk breast cancer families, who tested negative for pathogenic mutations in BRCA1 and BRCA2, are four times more likely to develop breast cancer compared to women in the general population. Sequencing of genes involved in genomic stability and DNA repair led to the identification of novel contributors to familial breast cancer risk. These include BLM and PALB2. Bloom's syndrome is a rare homozygous autosomal recessive chromosomal instability disorder with a high incidence of various types of neoplasia and is associated with breast cancer when in a heterozygous state. PALB2, on the other hand, binds to BRCA2 and together, they partake actively in DNA damage repair. Archived DNA samples of 66 BRCA1/2 negative high-risk breast cancer patients were retrospectively selected based on the presence of an extensive family history of the disease ( > 3 affecteds per family). All coding regions and splice-site boundaries of both genes were screened using High-Resolution Melting Analysis. Samples exhibiting variation were bi-directionally automated Sanger sequenced. The clinical significance of each variant was assessed using various in silico and splice site prediction algorithms. Comprehensive screening identified a total of 11 BLM and 26 PALB2 variants. The variants detected ranged from global to rare and included three novel mutations. Three BLM and two PALB2 likely pathogenic mutations were identified that could account for the disease in these extensive breast cancer families in the absence of BRCA mutations (BLM c.11T > A, p.V4D; BLM c.2603C > T, p.P868L; BLM c.3961G > A, p.V1321I; PALB2 c.421C > T, p.Gln141Ter; PALB2 c.508A > T, p.Arg170Ter). Conclusion: The study confirmed the contribution of pathogenic mutations in BLM and PALB2 to the familial breast cancer burden in South Africa. It explained the presence of the disease in 7.5% of the BRCA1/2 negative families with an extensive family history of breast cancer. Segregation analysis will be performed to confirm the clinical impact of these mutations for each of these families. These results justify the inclusion of both these genes in a comprehensive breast and ovarian next generation sequencing cancer panel and should be screened simultaneously with BRCA1 and BRCA2 as it might explain a significant percentage of familial breast and ovarian cancer in South Africa.

Keywords: Bloom Syndrome, familial breast cancer, PALB2, South Africa

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17581 Examining the Decision-Making Process of Hong Kong High School Students Regarding University Choices after 2019

Authors: Yuanyuan Song

Abstract:

Following the 2019 protests in Hong Kong, significant shifts occurred within society. This study aims to explore whether these events have had an impact on the university preferences of high school students. To delve into these questions, this research immerses itself in the forefront of Hong Kong's educational landscape. It encompasses field studies, interviews, and questionnaires administered to a diverse range of Hong Kong students, as well as their parents and teachers. The findings uncover that the majority of local Hong Kong students and parents possess a limited understanding of mainland China, and this perception has further soured since 2019. Interestingly, the inclination towards pursuing overseas education, particularly in countries like the UK and Australia, has experienced a steady rise. This trend persists despite the fact that esteemed Chinese universities extend preferential admissions policies to Hong Kong students.

Keywords: higher education, university choices, educational sociology, education in Hongkong

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17580 A CMOS-Integrated Hall Plate with High Sensitivity

Authors: Jin Sup Kim, Min Seo

Abstract:

An improved cross-shaped hall plate with high sensitivity is described in this paper. Among different geometries that have been simulated and measured using Helmholtz coil. The paper describes the physical hall plate design and implementation in a 0.18-µm CMOS technology. In this paper, the biasing is a constant voltage mode. In the voltage mode, magnetic field is converted into an output voltage. The output voltage is typically in the order of micro- to millivolt and therefore, it must be amplified before being transmitted to the outside world. The study, design and performance optimization of hall plate has been carried out with the COMSOL Multiphysics. It is used to estimate the voltage distribution in the hall plate with and without magnetic field and to optimize the geometry. The simulation uses the nominal bias current of 1mA. The applied magnetic field is in the range from 0 mT to 20 mT. Measured results of the one structure over the 10 available samples show for the best sensitivity of 2.5 %/T at 20mT.

Keywords: cross-shaped hall plate, sensitivity, CMOS technology, Helmholtz coil

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17579 Healthcare Social Entrepreneurship: A Positive Theory Applied to the Case of YOU Foundation in Nepal

Authors: Simone Rondelli, Damiano Rondelli, Bishesh Poudyal, Juan Jose Cabrera-Lazarini

Abstract:

One of the main obstacles for Social Entrepreneurship is to find a business model that is financially sustainable. In other words, the captured value generates enough cash flow to ensure business continuity and reinvestment for growth. Providing Health Services in poor countries for the uninsured population affected by a high-cost chronical disease is not the exception for this challenge. As a prime example, cancer has become a high impact on a global disease not only because of the high morbidity but also of the financial impact on both the patient family and health services in underdeveloped countries. Therefore, it is relevant to find a Social Entrepreneurship Model that provides affordable treatment for this disease while maintaining healthy finances not only for the patient but also for the organization providing the treatment. Using the methodology of Constructive Research, this paper applied a Positive Theory and four business models of Social Entrepreneurship to a case of a Private Foundation model whose mission is to address the challenge previously described. It was found that the Foundation analyzed, in this case, is organized as an Embedded Business Model and complies with the four propositions of the Positive Theory considered. It is recommended for this Private Foundation to explore implementing the Integrated Business Model to ensure more robust sustainability in the long term. It evolves as a scalable model that can attract investors interested in contributing to expanding this initiative globally.

Keywords: affordable treatment, global healthcare, social entrepreneurship theory, sustainable business model

Procedia PDF Downloads 148
17578 Solar Radiation Studies and Performance of Solar Panels for Three Cities of Sindh, Pakistan

Authors: M. A. Ahmed, Sidra A. Shaikh, M. W. Akhtar

Abstract:

Solar radiation on horizontal surface over three southern cities of Sindh, namely Karachi, Hyderabad and Nawabshah has been investigated to asses the feasibility of solar energy application for power generation. In the present work, measured data of bright sunshine hour of the region have been used to estimate the global and diffuse solar radiation. The regression coefficient 'a' and 'b' have been calculated using first order Angstrom type co-relation. The result obtained shows that the contribution of direct solar radiation is low and diffuse radiation is high during the monsoon months July and August for Karachi and Hyderabad. The sky remains clear from September to June, whereas for Nawabshah the global radiation remains high throughout the year. The potential of grid quality solar photovoltaic power in Karachi is estimated for 10 square meter area of solar panel.

Keywords: solar potential over Sindh, global and diffuse solar radiation, radiation over three cities of Sindh, solar panels

Procedia PDF Downloads 450
17577 Development of Flipped Classroom in Chemistry on 'Acid-Base' for Enrichment Science Classroom Students

Authors: Waratthaya Maneerattana, Piyarat Dornbundit

Abstract:

The study aimed to develop flipped classroom in Chemistry on ‘acid-base’ for high school students and study efficiency of students on academic achievement and problem-solving skills. The evaluating result from the experts showed that developed flipped classroom was ranked in high score level. The flipped classroom efficiency E1/E2 was higher than the criteria of 70/70. The flipped classroom was used by 24 students in grade 11 in the second semester of the academic year 2016 at Bodindecha (Sing Singhaseni) School. Sampling group was chosen using a purposive sampling approach. The results revealed that academic achievement and problem solving skills of students after studying flipped classroom was significantly higher at .05 level.

Keywords: flipped classroom, acid-base, academic achievement, problem solving skill

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17576 Computational Fluid Dynamics Simulation of a Boiler Outlet Header Constructed of Inconel Alloy 740H

Authors: Sherman Ho, Ahmed Cherif Megri

Abstract:

Headers play a critical role in conveying steam to regulate heating system temperatures. While various materials like steel grades 91 and 92 have been traditionally used for pipes, this research proposes the use of a robust and innovative material, INCONEL Alloy 740H. Boilers in power plant configurations are exposed to cycling conditions due to factors such as daily, seasonal, and yearly variations in weather. These cycling conditions can lead to the deterioration of headers, which are vital components with intricate geometries. Header failures result in substantial financial losses from repair costs and power plant shutdowns, along with significant public inconveniences such as the loss of heating and hot water. To address this issue and seek solutions, a mechanical analysis, as well as a structural analysis, are recommended. Transient analysis to predict heat transfer conditions is of paramount importance, as the direction of heat transfer within the header walls and the passing steam can vary based on the location of interest, load, and operating conditions. The geometry and material of the header are also crucial design factors, and the choice of pipe material depends on its usage. In this context, the heat transfer coefficient plays a vital role in header design and analysis. This research employs ANSYS Fluent, a numerical simulation program, to understand header behavior, predict heat transfer, and analyze mechanical phenomena within the header. Transient simulations are conducted to investigate parameters like heat transfer coefficient, pressure loss coefficients, and heat flux, with the results used to optimize header design.

Keywords: CFD, header, power plant, heat transfer coefficient, simulation using experimental data

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17575 Perceived Ethnic Discrimination, Aggression, and School Connectedness among Adolescents in Finland

Authors: Isik Z. Ulubas, Kaj Bjorkqvist

Abstract:

The relationships between perceived ethnic discrimination, peer aggression and school connectedness are being examined among 1,000 adolescents in Ostrobothnia, Finland with an online questionnaire. The study aims at investigating perceived ethnic discrimination in school environment by peers and teachers, and within society in general. Six types of aggressive behavior are measured: physical, verbal, indirect, and cyber aggression, in addition to both verbal and physical sexual harassment. High perceived ethnic discrimination is expected to be related with high aggression and low school connectedness. Adolescents who have special diet and clothing because of their cultural or religious background are expected to score higher on perceived ethnic discrimination and lower school connectedness. Adolescents who have lower domestic language skills (Finnish/Swedish) are expected to show lower school connectedness and higher perceived ethnic discrimination.

Keywords: adolescents, aggression, ethnic discrimination, school connectedness

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17574 Effect of Superabsorbent for the Improvement of Car Seat's Thermal Comfort

Authors: Funda Buyuk Mazari, Adnan Mazari, Antonin Havelka, Jakub Wiener, Jawad Naeem

Abstract:

The use of super absorbent polymers (SAP) for moisture absorption and comfort is still unexplored. In this research the efficiency of different SAP fibrous webs are determined under different moisture percentage to examine the sorption and desorption efficiency. The SAP fibrous web with low thickness and high moisture absorption are tested with multilayer sandwich structure of car seat cover to determine the moisture absorption through cover material. Sweating guarded hot plate (SGHP) from company Atlas is used to determine the moisture permeability of different car seat cover with superabsorbent layer closed with impermeable polyurethane foam. It is observed that the SAP fibrous layers are very effective in absorbing and desorbing water vapor under extreme high and low moisture percentages respectively. In extreme humid condition (95 %RH) the 20g of SAP layer absorbs nearly 3g of water vapor per hour and reaches the maximum absorption capacity in 6 hours.

Keywords: car seat, comfort, SAF, superabsorbent

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17573 Prevalence of Extended Spectrum of Beta Lactamase Producers among Gram Negative Uropathogens

Authors: Y. V. S. Annapurna, V. V. Lakshmi

Abstract:

Urinary tract infection (UTI) is one of the most common infectious diseases at the community level with a high rate of morbidity . This is further augmented by increase in the number of resistant and multi resistant strains of bacteria particularly by those producing Extended spectrum of beta lactamases. The present study was aimed at analysis of antibiograms of E.coli and Klebsiella sp causing urinary tract infections. Between November 2011 and April 2013, a total of 1120 urine samples were analyzed,. Antibiotic sensitivity testing was done with 542(48%) isolates of E.coli and 446(39%) of Klebsiella sp using the standard disc diffusion method against eleven commonly used antibiotics .Organisms showed high susceptibility to Amikacin and Netilimicin and low susceptibility to Cephalosporins. MAR index was calculated for the multidrug resistant strains. Maximum MAR index detected among the isolates was 0.9. Phenotypic identification for ESBL production was confirmed by double disk synergy test (DDST) according to CLSI guidelines. Plasmid profile of the isolates was carried out using alkaline hydrolysis method. Agarose-gel electrophoresis showed presence of high-molecular weight plasmid DNA among the ESBL strains. This study emphasizes the importance of indiscriminate use of antibiotics which if discontinued, in turn would prevent further development of bacterial drug resistance. For this, a proper knowledge of susceptibility pattern of uropathogens is necessary before prescribing empirical antibiotic therapy and it should be made mandatory.

Keywords: escherichia coli, extended spectrum of beta lactamase, Klebsiella spp, Uropathogens

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17572 Wildfire-Related Debris-Flow and Flooding Using 2-D Hydrologic Model

Authors: Cheong Hyeon Oh, Dongho Nam, Byungsik Kim

Abstract:

Due to the recent climate change, flood damage caused by local floods and typhoons has frequently occurred, the incidence rate and intensity of wildfires are greatly increased due to increased temperatures and changes in precipitation patterns. Wildfires cause primary damage, such as loss of forest resources, as well as secondary disasters, such as landslides, floods, and debris flow. In many countries around the world, damage and economic losses from secondary damage are occurring as well as the direct effects of forest fires. Therefore, in this study, the Rainfall-Runoff model(S-RAT) was used for the wildfire affected areas in Gangneung and Goseong, which occurred on April 2019, when the stability of vegetation and soil were destroyed by wildfires. Rainfall data from Typhoon Rusa were used in the S-RAT model, and flood discharge was calculated according to changes in land cover before and after wildfire damage. The results of the calculation showed that flood discharge increased significantly due to changes in land cover, as the increase in flood discharge increases the possibility of the occurrence of the debris flow and the extent of the damage, the debris flow height and range were calculated before and after forest fire using RAMMS. The analysis results showed that the height and extent of damage increased after wildfire, but the result value was underestimated due to the characteristics that using DEM and maximum flood discharge of the RAMMS model. This research was supported by a grant(2017-MOIS31-004) from Fundamental Technology Development Program for Extreme Disaster Response funded by Korean Ministry of Interior and Safety (MOIS). This paper work (or document) was financially supported by Ministry of the Interior and Safety as 'Human resoure development Project in Disaster management'.

Keywords: wildfire, debris flow, land cover, rainfall-runoff meodel S-RAT, RAMMS, height

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17571 Pattern of Bacterial Isolates and Antimicrobial Resistance at Ayder Comprehensive Specialized Referral Hospital in Northern Ethiopia: A Retrospective Study

Authors: Solomon Gebremariam, Mulugeta Naizigi, Aregawi Haileselassie

Abstract:

Background: Knowledge of the pattern of bacterial isolates and their antimicrobial susceptibility is crucial for guiding empirical treatment and infection prevention and control measures. Objective: The aim of this study was to analyze the pattern of bacterial isolates and their susceptibility patterns from various specimens. Methods: Retrospectively, a total of 1067 microbiological culture results that were isolated, characterized, and identified by standard microbiological methods and whose antibiotic susceptibility was determined using CLSI guidelines between 2017 and 2019 were retrieved and analyzed. Data were entered and analyzed using the Stata release 10.1 statistical package. Result: The positivity rate of culture was 26.04% (419/1609). The most common bacteria isolated were S. aureus 23.8% (94), E. coli 15.1% (60), Klebsiella pneumonia 14.1% (56), Pseudomonas aeruginosa 8.5% (34), and CONS 7.3% (29). S. aureus and CONS showed a high (58.1% - 96.2%) rate of resistance to most antibiotics tested. They were less resistant to Vancomycin which is 18.6% (13/70) and 11.8% (2/17), respectively. Similarly, the resistance of E. coli, Klebsella pneumonia, and Pseudomonas aeruginosa was high (69.4% - 100%) to most antibiotics. They were less resistant to Ciprofloxacilin, which is 41.1% (23/56), 19.2% (10/52), and 16.1% (5/31), respectively. Conclusion: This study has shown that there is a high rate of antibiotic resistance among bacterial isolates in this hospital. A combination of Vancomycin and Ciprofloxacin should be considered in the choice of antibiotics for empirical treatment of suspected infections due to S. aureus, CONS, E. coli, Klebsiella pneumonia, Pseudomonas such as in infections within hospital setup.

Keywords: antimicrobial, resistance, bacteria, hospital

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17570 Simulation of Welded Steel Tube Subjected to Internal Pressure

Authors: H. Zedira, M. T. Hannachi, H. Djebaili, B. Daheche

Abstract:

The rapid pace of technology development and strong competition in the market, prompted us to consider the field of manufacturing of steel pipes by a process complies fully with the requirements of industrial induction welding is high frequency (HF), this technique is better known today in Algeria, more precisely for the manufacture of tubes diameters Single Annabib TG Tebessa. The aim of our study is based on the characterization of processes controlling the mechanical behavior of steel pipes (type E24-2), welded by high frequency induction, considering the different tests and among the most destructive known test internal pressure. The internal pressure test is performed according to the application area of welded pipes, or as leak test, either as a test of strength (bursting). All tubes are subjected to a hydraulic test pressure of 50 bar kept at room temperature for a period of 6 seconds. This study provides information that helps optimize the design and implementation to predict the behavior of the tubes during operation.

Keywords: castem, pressure, stress, tubes, thickness

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17569 Ground Surface Temperature History Prediction Using Long-Short Term Memory Neural Network Architecture

Authors: Venkat S. Somayajula

Abstract:

Ground surface temperature history prediction model plays a vital role in determining standards for international nuclear waste management. International standards for borehole based nuclear waste disposal require paleoclimate cycle predictions on scale of a million forward years for the place of waste disposal. This research focuses on developing a paleoclimate cycle prediction model using Bayesian long-short term memory (LSTM) neural architecture operated on accumulated borehole temperature history data. Bayesian models have been previously used for paleoclimate cycle prediction based on Monte-Carlo weight method, but due to limitations pertaining model coupling with certain other prediction networks, Bayesian models in past couldn’t accommodate prediction cycle’s over 1000 years. LSTM has provided frontier to couple developed models with other prediction networks with ease. Paleoclimate cycle developed using this process will be trained on existing borehole data and then will be coupled to surface temperature history prediction networks which give endpoints for backpropagation of LSTM network and optimize the cycle of prediction for larger prediction time scales. Trained LSTM will be tested on past data for validation and then propagated for forward prediction of temperatures at borehole locations. This research will be beneficial for study pertaining to nuclear waste management, anthropological cycle predictions and geophysical features

Keywords: Bayesian long-short term memory neural network, borehole temperature, ground surface temperature history, paleoclimate cycle

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17568 Stability of Concrete Moment Resisting Frames in View of Current Codes Requirements

Authors: Mahmoud A. Mahmoud, Ashraf Osman

Abstract:

In this study, the different approaches currently followed by design codes to assess the stability of buildings utilizing concrete moment resisting frames structural system are evaluated. For such purpose, a parametric study was performed. It involved analyzing group of concrete moment resisting frames having different slenderness ratios (height/width ratios), designed for different lateral loads to vertical loads ratios and constructed using ordinary reinforced concrete and high strength concrete for stability check and overall buckling using code approaches and computer buckling analysis. The objectives were to examine the influence of such parameters that directly linked to frames’ lateral stiffness on the buildings’ stability and evaluates the code approach in view of buckling analysis results. Based on this study, it was concluded that, the most susceptible buildings to instability and magnification of second order effects are buildings having high aspect ratios (height/width ratio), having low lateral to vertical loads ratio and utilizing construction materials of high strength. In addition, the study showed that the instability limits imposed by codes are mainly mathematical to ensure reliable analysis not a physical ones and that they are in general conservative. Also, it has been shown that the upper limit set by one of the codes that second order moment for structural elements should be limited to 1.4 the first order moment is not justified, instead, the overall story check is more reliable.

Keywords: buckling, lateral stability, p-delta, second order

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17567 Prevalence and Associated Factors of Protein-Energy Malnutrition Among Children Aged 6-59 Months in Babile Town from April to June 2016

Authors: Tajudin Ahmed

Abstract:

Malnutrition is a significant problem in developing countries, particularly among children, due to inadequate diets, lack of proper care, and unequal distribution of food within households. High rates of malnutrition have been shown in Ethiopia, including stunting, underweight, and wasting. This study aims to assess the prevalence and associated factors of Protein-Energy Malnutrition (PEM) among children aged 6-59 months in Babile Town. The study utilized a community-based cross-sectional design conducted in Babile Town, Eastern Ethiopia. Two kebeles were randomly selected, and a census was conducted to identify eligible households. A total of 391 households with children aged 6-59 months were included in the study. Data was collected using structured questionnaires, and anthropometric measurements were taken to assess the weight and height of the children. The study found that a majority of the mothers (72.34%) and fathers (43%) had no formal education. Among the mothers who could read and write, a small percentage had completed primary (14%) or secondary (14%) education, and even fewer had higher education (2.7%). Similarly, among the fathers who could read and write, a majority had completed primary (46.15%) or secondary (27.22%) education, with smaller percentages completing preparatory (8.4%) or higher education (6.29%). The prevalence of malnutrition in the study area was high, with 38.85% of children experiencing stunting (8.2% severely stunted), 50.13% wasting (9% severely wasted), and 41.43% underweight (6.65% severely underweight). These findings indicate a significant burden of malnutrition in Babile Town, likely exacerbated by the high prevalence of infectious diseases such as diarrhea. The study concludes that the prevalence of malnutrition, particularly stunting, wasting, and underweight, is high in Babile Town. The findings indicate the urgent need for interventions to address malnutrition and improve nutrition and healthcare practices in the study area. These results can serve as a baseline for future studies and inform policymakers and healthcare providers in their efforts to combat childhood malnutrition.

Keywords: protein-energy malnutrition, children 6-59 month age babble town, Marasmus

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17566 BI- And Tri-Metallic Catalysts for Hydrogen Production from Hydrogen Iodide Decomposition

Authors: Sony, Ashok N. Bhaskarwar

Abstract:

Production of hydrogen from a renewable raw material without any co-synthesis of harmful greenhouse gases is the current need for sustainable energy solutions. The sulfur-iodine (SI) thermochemical cycle, using intermediate chemicals, is an efficient process for producing hydrogen at a much lower temperature than that required for the direct splitting of water. No net byproduct forms in the cycle. Hydrogen iodide (HI) decomposition is a crucial reaction in this cycle, as the product, hydrogen, forms only in this step. It is an endothermic, reversible, and equilibrium-limited reaction. The theoretical equilibrium conversion at 550°C is just a meagre of 24%. There is a growing interest, therefore, in enhancing the HI conversion to near-equilibrium values at lower reaction temperatures and by possibly improving the rate. The reaction is relatively slow without a catalyst, and hence catalytic decomposition of HI has gained much significance. Bi-metallic Ni-Co, Ni-Mn, Co-Mn, and tri-metallic Ni-Co-Mn catalysts over zirconia support were tested for HI decomposition reaction. The catalysts were synthesized via a sol-gel process wherein Ni was 3wt% in all the samples, and Co and Mn had equal weight ratios in the Co-Mn catalyst. Powdered X-ray diffraction and Brunauer-Emmett-Teller surface area characterizations indicated the polycrystalline nature and well-developed mesoporous structure of all the samples. The experiments were performed in a vertical laboratory-scale packed bed reactor made of quartz, and HI (55 wt%) was fed along with nitrogen at a WHSV of 12.9 hr⁻¹. Blank experiments at 500°C for HI decomposition suggested conversion of less than 5%. The activities of all the different catalysts were checked at 550°C, and the highest conversion of 23.9% was obtained with the tri-metallic 3Ni-Co-Mn-ZrO₂ catalyst. The decreasing order of the performance of catalysts could be expressed as: 3Ni-Co-Mn-ZrO₂ > 3Ni-2Co-ZrO₂ > 3Ni-2Mn-ZrO₂ > 2.5Co-2.5Mn-ZrO₂. The tri-metallic catalyst remained active till 360 mins at 550°C without any observable drop in its activity/stability. Among the explored catalyst compositions, the tri-metallic catalyst certainly has a better performance for HI conversion when compared to the bi-metallic ones. Owing to their low costs and ease of preparation, these trimetallic catalysts could be used for large-scale hydrogen production.

Keywords: sulfur-iodine cycle, hydrogen production, hydrogen iodide decomposition, bi-, and tri-metallic catalysts

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17565 Experimental Investigation and Constitutive Modeling of Volume Strain under Uniaxial Strain Rate Jump Test in HDPE

Authors: Rida B. Arieby, Hameed N. Hameed

Abstract:

In this work, tensile tests on high density polyethylene have been carried out under various constant strain rate and strain rate jump tests. The dependency of the true stress and specially the variation of volume strain have been investigated, the volume strain due to the phenomena of damage was determined in real time during the tests by an optical extensometer called Videotraction. A modified constitutive equations, including strain rate and damage effects, are proposed, such a model is based on a non-equilibrium thermodynamic approach called (DNLR). The ability of the model to predict the complex nonlinear response of this polymer is examined by comparing the model simulation with the available experimental data, which demonstrate that this model can represent the deformation behavior of the polymer reasonably well.

Keywords: strain rate jump tests, volume strain, high density polyethylene, large strain, thermodynamics approach

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17564 High Culture or Low Culture: The Propagation and Popularization of the Classic of Poetry in Modern China

Authors: Fang Tang

Abstract:

A major Confucian masterpiece and the earliest-known poetry anthology (composed approximately 1046-771 BCE), The Classic of Poetry, reflects different cultures in ancient China. It is regarded as a Chinese classic and one of the world’s most significant written works, an essential part of our global cultural heritage. This paper explores how the ancient Chinese classic became transformed into part of popular culture, found in folk songs circulated in Fangxian county, a mountainous location in Hubei province in central mainland China. It is the hometown of one of the most well-known authors of The Classic of Poetry, whose name is Yin Jifu. Local villagers process, refine, and recreate these poems into popular folk songs, which have been handed down from generation to generation. The folk songs based on The Classic of Poetry vividly reflect local customs, life styles, and various cultural activities. After thousands of years of singing these traditional songs, the region has become an important area to maintain part of Chinese cultural heritages; here, the original high culture is converted into a popular culture that is absorbed into people’s daily life. Based on a year’s field research and many interviews with local singers, this paper explores the ways in which locals have transformed the contents of The Classic of Poetry. It examines how today these popular folk songs become part of much-treasured culture heritage, illustrating the transformation of traditional high culture into popular culture. The paper argues that the modern adaptations of the traditional poems of The Classic of Poetry combine both oral and written cultural heritage and reflects the interaction between ancient Chinese official literature and folk literature. The paper also explores the reasons why the folk songs of The Classic of Poetry are so popular in the area, including the influences of its author Yin Jifu, the impact of ancient diasporic culture from the political centre to remote rural areas, and the interactions of local cultures (famous as Chu culture) and Chinese mainstream cultural policies.

Keywords: high/low culture, The Classic of Poetry, the functions of media, cultural policy

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17563 Growth and Development of Membranes in Gas Sequestration

Authors: Sreevalli Bokka

Abstract:

The process of reducing the intensity of the carbon from a process or stream into the atmosphere is termed Decarbonization. Of the various technologies that are emerging to capture or reduce carbon intensity, membranes are emerging as a key player in separating carbon from a gas stream, such as industrial effluent air and others. Due to the advantage of high surface area and low flow resistance, fiber membranes are emerging widely for gas separation applications. A fiber membrane is a semipermeable barrier that is increasingly used for filtration and separation applications needing high packing density. A few of the many applications are in water desalination, medical applications, bioreactors, and gas separations applications. Only a few polymeric membranes were studied for fabricating fiber membranes such as cellulose acetate, Polysulfone, and Polyvinylidene fluoride. A few of the challenges of using fiber membranes are fouling and weak mechanical properties, leading to the breakage of membranes. In this work, the growth of fiber membranes and challenges for future developments in the filtration and gas separation applications are presented.

Keywords: membranes, filtration, separations, polymers, carbon capture

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17562 Women Unemployment in India: Comparative Analysis of Indian States Having Low and High Women Participation in Labour Force

Authors: Anesha Atul Shende

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When we are aiming at high goals for economic development, such as sustainable growth and development of the economy, poverty reduction, reduction in inequality, etc., we must not forget to include each and everyone in the society in the process of achieving these goals. This study particularly talks about women participation in economic activities. The analysis is primarily done with a special focus on Indian states. The study analyses the female labour force participation rate in all many states in India. It makes a comparison between the states having low female Labour force participation with the states that have comparatively high female Labour population. In the beginning, data has been provided to know the current state of gender biases in employment. It has been found that the male workforce is dominant all across India. Further, the study highlights the major reasons for low women participation in economic activities in some of the backward states in India like Bihar, etc. These reasons basically talk about economic, cultural, and social factors that are responsible for women unemployment. Afterward, it analyses the reasons behind comparatively higher women participation in all other states in India. The case of the north-eastern state of Telangana and Tamil Nadu have been analysed in brief. These states show the improvements in female Labour participation over a few decades. This is because of government policies that have been adopted, women-friendly workplaces, availability of quality jobs for women, etc. Organization like women UN has recognized the social and economic benefits of having active women Labour force in the country. If women unemployment declines, it will improve the growth rate of the nation as well as the welfare of the society. The study discusses the reasons why an economy must try to increase women workforce participation. It further provides suggestions to improve the conditions in backward states in India, where the female unemployment rate is high. One must understand that policy interventions and government schemes are a few of the ways to recognize this issue and work on it. However, the conditions will improve only when the changes would happen from the ground level with social and moral support to the women.

Keywords: women unemployment, labour force participation, women empowerment, economic growth and development, gender disparity

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17561 Preparation of Fe3Si/Ferrite Micro-and Nano-Powder Composite

Authors: Radovan Bures, Madgalena Streckova, Maria Faberova, Pavel Kurek

Abstract:

Composite material based on Fe3Si micro-particles and Mn-Zn nano-ferrite was prepared using powder metallurgy technology. The sol-gel followed by autocombustion process was used for synthesis of Mn0.8Zn0.2Fe2O4 ferrite. 3 wt.% of mechanically milled ferrite was mixed with Fe3Si powder alloy. Mixed micro-nano powder system was homogenized by the Resonant Acoustic Mixing using ResodynLabRAM Mixer. This non-invasive homogenization technique was used to preserve spherical morphology of Fe3Si powder particles. Uniaxial cold pressing in the closed die at pressure 600 MPa was applied to obtain a compact sample. Microwave sintering of green compact was realized at 800°C, 20 minutes, in air. Density of the powders and composite was measured by Hepycnometry. Impulse excitation method was used to measure elastic properties of sintered composite. Mechanical properties were evaluated by measurement of transverse rupture strength (TRS) and Vickers hardness (HV). Resistivity was measured by 4 point probe method. Ferrite phase distribution in volume of the composite was documented by metallographic analysis. It has been found that nano-ferrite particle distributed among micro- particles of Fe3Si powder alloy led to high relative density (~93%) and suitable mechanical properties (TRS >100 MPa, HV ~1GPa, E-modulus ~140 GPa) of the composite. High electric resistivity (R~6.7 ohm.cm) of prepared composite indicate their potential application as soft magnetic material at medium and high frequencies.

Keywords: micro- and nano-composite, soft magnetic materials, microwave sintering, mechanical and electric properties

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17560 Bending Behaviour of Fiber Reinforced Polymer Composite Stiffened Panel Subjected to Transverse Loading

Authors: S. Kumar, Rajesh Kumar, S. Mandal

Abstract:

Fiber Reinforced Polymer (FRP) is gaining popularity in many branch of engineering and various applications due to their light weight, specific strength per unit weight and high stiffness in particular direction. As the strength of material is high it can be used in thin walled structure as industrial roof sheds satisfying the strength constraint with comparatively lesser thickness. Analysis of bending behavior of FRP panel has been done here with variation in oriented angle of stiffener panels, fiber orientation, aspect ratio and boundary conditions subjected to transverse loading by using Finite Element Method. The effect of fiber orientation and thickness of ply has also been studied to determine the minimum thickness of ply for optimized section of stiffened FRP panel.

Keywords: bending behavior, fiber reinforced polymer, finite element method, orientation of stiffeners

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17559 Different Data-Driven Bivariate Statistical Approaches to Landslide Susceptibility Mapping (Uzundere, Erzurum, Turkey)

Authors: Azimollah Aleshzadeh, Enver Vural Yavuz

Abstract:

The main goal of this study is to produce landslide susceptibility maps using different data-driven bivariate statistical approaches; namely, entropy weight method (EWM), evidence belief function (EBF), and information content model (ICM), at Uzundere county, Erzurum province, in the north-eastern part of Turkey. Past landslide occurrences were identified and mapped from an interpretation of high-resolution satellite images, and earlier reports as well as by carrying out field surveys. In total, 42 landslide incidence polygons were mapped using ArcGIS 10.4.1 software and randomly split into a construction dataset 70 % (30 landslide incidences) for building the EWM, EBF, and ICM models and the remaining 30 % (12 landslides incidences) were used for verification purposes. Twelve layers of landslide-predisposing parameters were prepared, including total surface radiation, maximum relief, soil groups, standard curvature, distance to stream/river sites, distance to the road network, surface roughness, land use pattern, engineering geological rock group, topographical elevation, the orientation of slope, and terrain slope gradient. The relationships between the landslide-predisposing parameters and the landslide inventory map were determined using different statistical models (EWM, EBF, and ICM). The model results were validated with landslide incidences, which were not used during the model construction. In addition, receiver operating characteristic curves were applied, and the area under the curve (AUC) was determined for the different susceptibility maps using the success (construction data) and prediction (verification data) rate curves. The results revealed that the AUC for success rates are 0.7055, 0.7221, and 0.7368, while the prediction rates are 0.6811, 0.6997, and 0.7105 for EWM, EBF, and ICM models, respectively. Consequently, landslide susceptibility maps were classified into five susceptibility classes, including very low, low, moderate, high, and very high. Additionally, the portion of construction and verification landslides incidences in high and very high landslide susceptibility classes in each map was determined. The results showed that the EWM, EBF, and ICM models produced satisfactory accuracy. The obtained landslide susceptibility maps may be useful for future natural hazard mitigation studies and planning purposes for environmental protection.

Keywords: entropy weight method, evidence belief function, information content model, landslide susceptibility mapping

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17558 Development of Composition and Technology of Vincristine Nanoparticles Using High-Molecular Carbohydrates of Plant Origin

Authors: L. Ebralidze, A. Tsertsvadze, D. Berashvili, A. Bakuridze

Abstract:

Current cancer therapy strategies are based on surgery, radiotherapy and chemotherapy. The problems associated with chemotherapy are one of the biggest challenges for clinical medicine. These include: low specificity, broad spectrum of side effects, toxicity and development of cellular resistance. Therefore, anti-cance drugs need to be develop urgently. Particularly, in order to increase efficiency of anti-cancer drugs and reduce their side effects, scientists work on formulation of nano-drugs. The objective of this study was to develop composition and technology of vincristine nanoparticles using high-molecular carbohydrates of plant origin. Plant polysacharides, particularly, soy bean seed polysaccharides, flaxseed polysaccharides, citrus pectin, gum arabic, sodium alginate were used as objects. Based on biopharmaceutical research, vincristine containing nanoparticle formulations were prepared. High-energy emulsification and solvent evaporation methods were used for preparation of nanosystems. Polysorbat 80, polysorbat 60, sodium dodecyl sulfate, glycerol, polyvinyl alcohol were used in formulation as emulsifying agent and stabilizer of the system. The ratio of API and polysacharides, also the type of the stabilizing and emulsifying agents are very effective on the particle size of the final product. The influence of preparation technology, type and concentration of stabilizing agents on the properties of nanoparticles were evaluated. For the next stage of research, nanosystems were characterized. Physiochemical characterization of nanoparticles: their size, shape, distribution was performed using Atomic force microscope and Scanning electron microscope. The present study explored the possibility of production of NPs using plant polysaccharides. Optimal ratio of active pharmaceutical ingredient and plant polysacharids, the best stabilizer and emulsifying agent was determined. The average range of nanoparticles size and shape was visualized by SEM.

Keywords: nanoparticles, target delivery, natural high molecule carbohydrates, surfactants

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17557 Prevalence and Antimicrobial Resistance of Salmonella spp. Isolated from Pigs at Slaughterhouses in Northeast of Thailand

Authors: Sunpetch Angkititrakul, Seree Klaengair, Dusadee Phongaran, Arunee Ritthipanun

Abstract:

The objective of this study is to determine the prevalence and antimicrobial resistance pattern of Salmonella spp. isolated from pigs at slaughterhouses in the northeast of Thailand. During 2015-2016, all samples were isolated and identified by ISO 6579:2002. A total of 699 samples of rectal swab were collected and isolated for the presence of Salmonella. Salmonella was detected in 275 of 699 (39.34%) samples. 24 serovars were identified in the 275 isolates. The most prevalent serovars were rissen (36.97%), S. enterica ser.4,5,12:i: (25.35%) and typhimurium (21.33%). In this study, 76.30% of the isolates were resistant to at least one antimicrobial drug and 38.39% were multidrug resistant. The highest resistances were found in ampicillin (69.20%), tetracycline (66.35%), sulfamethoxazole/trimethoprim (35.55%) and chloramphenicol (9.00%) The results showed high prevalence of Salmonella spp. in pigs and high antimicrobial resistance among the isolates, and indicated the need for monitoring program to control Salmonella contamination and reduce the dissemination of antimicrobial resistance in pig supply chain.

Keywords: prevalence, antimicrobial resistance, Salmonella spp., pig

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17556 Evidence of Climate Change from Statistical Analysis of Temperature and Rainfall Data of Kaduna State, Nigeria

Authors: Iliya Bitrus Abaje

Abstract:

This study examines the evidence of climate change scenario in Kaduna State from the analysis of temperature and rainfall data (1976-2015) from three meteorological stations along a geographic transect from the southern part to the northern part of the State. Different statistical methods were used in determining the changes in both the temperature and rainfall series. The result of the linear trend lines revealed a mean increase in average temperature of 0.73oC for the 40 years period of study in the State. The plotted standard deviation for the temperature anomalies generally revealed that years of temperatures above the mean standard deviation (hotter than the normal conditions) in the last two decades (1996-2005 and 2006-2015) were more than those below (colder than the normal condition). The Cramer’s test and student’s t-test generally revealed an increasing temperature trend in the recent decades. The increased in temperature is an evidence that the earth’s atmosphere is getting warmer in recent years. The linear trend line equation of the annual rainfall for the period of study showed a mean increase of 316.25 mm for the State. Findings also revealed that the plotted standard deviation for the rainfall anomalies, and the 10-year non-overlapping and 30-year overlapping sub-periods analysis in all the three stations generally showed an increasing trend from the beginning of the data to the recent years. This is an evidence that the study area is now experiencing wetter conditions in recent years and hence climate change. The study recommends diversification of the economic base of the populace with emphasis on moving away from activities that are sensitive to temperature and rainfall extremes Also, appropriate strategies to ameliorate the scourge of climate change at all levels/sectors should always take into account the recent changes in temperature and rainfall amount in the area.

Keywords: anomalies, linear trend, rainfall, temperature

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17555 Literature Review on the Barriers to Access Credit for Small Agricultural Producers and Policies to Mitigate Them in Developing Countries

Authors: Margarita Gáfaro, Karelys Guzmán, Paola Poveda

Abstract:

This paper establishes the theoretical aspects that explain the barriers to accessing credit for small agricultural producers in developing countries and identifies successful policy experiences to mitigate them. We will test two hypotheses. The first one is that information asymmetries, high transaction costs and high-risk exposure limit the supply of credit to small agricultural producers in developing countries. The second hypothesis is that low levels of financial education and productivity and high uncertainty about the returns of agricultural activity limit the demand for credit. To test these hypotheses, a review of the theoretical and empirical literature on access to rural credit in developing countries will be carried out. The first part of this review focuses on theoretical models that incorporate information asymmetries in the credit market and analyzes the interaction between these asymmetries and the characteristics of the agricultural sector in developing countries. Some of the characteristics we will focus on are the absence of collateral, the underdevelopment of the judicial systems and insurance markets, and the high dependence on climatic factors of production technologies. The second part of this review focuses on the determinants of credit demand by small agricultural producers, including the profitability of productive projects, security conditions, risk aversion or loss, financial education, and cognitive biases, among others. There are policies that focus on resolving these supply and demand constraints and managing to improve credit access. Therefore, another objective of this paper is to present a review of effective policies that have promoted access to credit for smallholders in the world. For this, information available in policy documents will be collected. This information will be complemented by interviews with officials in charge of the design and execution of these policies in a subset of selected countries. The information collected will be analyzed in light of the conceptual framework proposed in the first two parts of this section. The barriers to access to credit that each policy attempts to resolve and the factors that could explain its effectiveness will be identified.

Keywords: agricultural economics, credit access, smallholder, developing countries

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17554 Influence of Copper-Methionine on Hematological and Biochemical Changes and Ascites Incidence in Cold-Stressed Broilers

Authors: M. Bagheri Varzaneh, H. R. Rahmani, R. Jahanian

Abstract:

The present study aimed to investigate the effects of copper-methionine on ascites incidence and hematological, morphological and enzymatic responses in broiler chickens. A total of 480 one-day-old Ross 308 broiler chicks were used in a completely randomized design in a 2×3 factorial arrangement of treatments including two ambient temperatures (thermoneutral and cold stress) and three copper levels (0, 100, and 200 mg/kg as copper-methionine) with 4 replicates (20 birds in each replicate). Broilers were kept in an environmentally-controlled room from 1 to 28 days; then, half of them exposed to cold temperature from 28 to 45 days of age. The birds were sacrificed at days 38 and 45 of age. Heparinized blood samples were collected to measure hematocrit, hemoglobin concentration, red blood cell (RBC) count, alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Heart, lungs, liver, and spleen were collected and weighed separately on a sensitive digital scale. At d 38 of age, none of hematological variables, enzymatic parameters, and relative weights of organs were affected by treatments. Ascitic broilers were observed in group subjected to cold temperature and control diet (without supplemental copper) at d 45 of age. Relative weight of lungs and relative weight of heart in broilers fed on copper-methionine supplemented diets in cold temperature were lower compared with other groups. Relative liver weight, ALT, AST activities, and hematological parameters such as hematocrit, hemoglobin concentration, red blood cell count in ascitic broilers were significantly increased. In contrast, a significant decrease of the relative weight of spleen was shown in these chickens. The results showed that dietary supplementation with copper–methionine can decrease probability of ascites incidence in broilers chicks, especially under cold condition.

Keywords: ascites, cold temperature, copper-methionine, cold-stressed broiler

Procedia PDF Downloads 640