Search results for: high performance polypropylene fibre
26221 Effects of Voltage Pulse Characteristics on Some Performance Parameters of LiₓCoO₂-based Resistive Switching Memory Devices
Authors: Van Son Nguyen, Van Huy Mai, Alec Moradpour, Pascale Auban Senzier, Claude Pasquier, Kang Wang, Pierre-Antoine Albouy, Marcelo J. Rozenberg, John Giapintzakis, Christian N. Mihailescu, Charis M. Orfanidou, Thomas Maroutian, Philippe Lecoeur, Guillaume Agnus, Pascal Aubert, Sylvain Franger, Raphaël Salot, Nathalie Brun, Katia March, David Alamarguy, Pascal ChréTien, Olivier Schneegans
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In the field of Nanoelectronics, a major research activity is being developed towards non-volatile memories. To face the limitations of existing Flash memory cells (endurance, downscaling, rapidity…), new approaches are emerging, among them resistive switching memories (Re-RAM). In this work, we analysed the behaviour of LixCoO2 oxide thin films in electrode/film/electrode devices. Preliminary results have been obtained concerning the influence of bias pulses characteristics (duration, value) on some performance parameters, such as endurance and resistance ratio (ROFF/RON). Besides, Conducting Probe Atomic Force Microscopy (CP-AFM) characterizations of the devices have been carried out to better understand some causes of performance failure, and thus help optimizing the switching performance of such devices.Keywords: non volatile resistive memories, resistive switching, thin films, endurance
Procedia PDF Downloads 61126220 Modelling and Simulation of Cascaded H-Bridge Multilevel Single Source Inverter Using PSIM
Authors: Gaddafi Sani Shehu, Tankut Yalcınoz, Abdullahi Bala Kunya
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Multilevel inverters such as flying capacitor, diode-clamped, and cascaded H-bridge inverters are very popular particularly in medium and high power applications. This paper focuses on a cascaded H-bridge module using a single direct current (DC) source in order to generate an 11-level output voltage. The noble approach reduces the number of switches and gate drivers, in comparison with a conventional method. The anticipated topology produces more accurate result with an isolation transformer at high switching frequency. Different modulation techniques can be used for the multilevel inverter, but this work features modulation techniques known as selective harmonic elimination (SHE).This modulation approach reduces the number of carriers with reduction in Switching Losses, Total Harmonic Distortion (THD), and thereby increasing Power Quality (PQ). Based on the simulation result obtained, it appears SHE has the ability to eliminate selected harmonics by chopping off the fundamental output component. The performance evaluation of the proposed cascaded multilevel inverter is performed using PSIM simulation package and THD of 0.94% is obtained.Keywords: cascaded H-bridge multilevel inverter, power quality, selective harmonic elimination
Procedia PDF Downloads 41926219 Effect of Project Control Practices on the Performance of Building Construction Companies in Uganda: A Case Study of Kampala City
Authors: Tukundane Hillary
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This research paper analytically evaluates the project control practice levels used by the building construction companies within Kampala, Uganda. The research also assesses the outcome of project control practices on the productivity of the companies. The research was performed to ascertain the current control practices among 160 respondents from various construction companies registered with the Uganda Registration Services Bureau. This research used amalgamation from multiple literature to obtain the variables. The research adopts 34 standard control practices from four vital project control duties: planning, monitoring, analyzing, and reporting. These project control tasks were organized using mean response ratings grounded on their relevance to the construction companies. Results showed that evaluating performance with the use of curves (4.32), timely access to information and encouragement (4.55), report representation using quantitative tools 4.75, and cost value comparison application during analysis (4.76) were rated least among the control practices. On the other hand, the top project control practices included formulation of the project schedule (8.88), Project feasibility validation (8.86), Budgeting for each activity (8.84), Key project route definition (8.81), Team awareness of the budget (8.77), Setting realistic targets for projects (8.50) and Consultation from subcontractors (8.74). From the results obtained by the sample respondents specified, it can be concluded that planning is the most vital project control task practiced in the building construction industry in Uganda. In addition, this research ascertained a substantial relationship between project control practices and the performance of building construction companies. Accordingly, this research recommends that project control practices be effectively observed by both contracting and consulting companies to enhance their overall performance and governance.Keywords: cost value, project control, cost control, time control, project performance, control practices
Procedia PDF Downloads 7426218 Novel Approach to Design of a Class-EJ Power Amplifier Using High Power Technology
Authors: F. Rahmani, F. Razaghian, A. R. Kashaninia
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This article proposes a new method for application in communication circuit systems that increase efficiency, PAE, output power and gain in the circuit. The proposed method is based on a combination of switching class-E and class-J and has been termed class-EJ. This method was investigated using both theory and simulation to confirm ~72% PAE and output power of > 39 dBm. The combination and design of the proposed power amplifier accrues gain of over 15dB in the 2.9 to 3.5 GHz frequency bandwidth. This circuit was designed using MOSFET and high power transistors. The load- and source-pull method achieved the best input and output networks using lumped elements. The proposed technique was investigated for fundamental and second harmonics having desirable amplitudes for the output signal.Keywords: power amplifier (PA), high power, class-J and class-E, high efficiency
Procedia PDF Downloads 49226217 Multi Objective Optimization for Two-Sided Assembly Line Balancing
Authors: Srushti Bhatt, M. B. Kiran
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Two-sided assembly line balancing problem is yet to be addressed simply to compete for the global market for manufacturers. The task assigned in an ordered sequence to get optimum performance of the system is known as assembly line balancing problem mainly classified as single and two sided. It is very challenging in manufacturing industries to balance two-sided assembly line, wherein the set of sequential workstations the task operations are performed in two sides of the line. The conflicting major objective in two-sided assembly line balancing problem is either to maximize /minimize the performance parameters. The present study emphases on combining different evolutionary algorithm; ant colony, Tabu search and petri net method; and compares their results of an algorithm for solving two-sided assembly line balancing problem. The concept of multi objective optimization of performance parameters is now a day adopted to make a decision involving more than one objective function to be simultaneously optimized. The optimum result can be expected among the selected methods using multi-objective optimization. The performance parameters considered in the present study are a number of workstation, slickness and smoothness index. The simulation of the assembly line balancing problem provides optimal results of classical and practical problems.Keywords: Ant colony, petri net, tabu search, two sided ALBP
Procedia PDF Downloads 27826216 Physical Exertion and Fatigue: A Breakthrough in Choking Sphere
Authors: R. Maher, D. Marchant, F. Fazel
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Choking in sport has been defined as ‘an acute performance breakdown’, and is generally explained through a range of contributory antecedents, factors, and explanatory theories. The influence of mental antecedents on an athlete’s performance under pressure has been widely examined through numerous studies. Researchers have only recently begun to investigate the influence of physical effort and associated residual fatigue as a potential contributor to choking in sport. Consequently, the initial aim of the present study was to examine the extent to which both physical exertion and pressure affect free-throw shooting performance. It was hypothesized that the free-throw shooting scores would decline under manipulated conditions. Design and Methods: Using a within-subjects design, 50 student-athletes were assigned to four manipulated conditions: (a) higher pressure-running, (b) higher pressure-no running, (c) lower pressure-running, and (d) lower pressure-no running. The physical exertion was manipulated by including a 56 meter shuttle-run in two of the running conditions. The pressure was manipulated with the presence of an audience, video-recording, performance contingent rewards, and weighting successful shots in the higher pressure conditions. A repeated measure analysis of variance was used to analyse the data. Results: The free-throw performance significantly deteriorated under manipulated physical exertion F (1, 49) = 10.13, p = .003, ηp 2 = .17 and pressure conditions F (1, 49) = 5.25, p = .02, ηp 2 = .09. The lowest free-throw scores were observed in the higher pressure-running condition, whereas the highest free-throw scores were reported in the lower pressure-no running condition. Conclusions: Physical exertion and the associated residual fatigue were contributors to choking. The results of the present study herald a new concept in choking research and yield a practical platform for use by athletes, coaches, and sport psychologists to better manage the psychological and physiological aspects of performance under pressure.Keywords: anxiety, basketball, choking, fatigue, free-throw shooting, physical exertion
Procedia PDF Downloads 28626215 Dietary Supplementation of Betaine and Response to Warm Weather in Broiler Chicken: A Review
Authors: Hassan Nabipour Afrouzi, Naser Mahmoudnia
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Broiler production has increased rapidly in tropical and subtropical regions in the past and sustained growth is forecast for the future. One of the greatest challenges to efficient production in these regions is reduced performance from warm and hot weather conditions. There are many ways to decrease these detrimental effects of heat on broiler chickens. One way is to supplement broiler diet with betaine added to feed or drinking water. A review of the results of this study suggest that betaine supplement was effective to significantly improve body weight and feed conversion ratio at the initial stages of growth but not in the finisher stages (P<0/05). It was also demonstrated that the use of betaine significantly reduced the percentage of abdominal meat and the percentage of breast meat (P<0/05), but had no effect on other carcass compositions. Betaine may improve the digestibility of specific nutrients. Betaine, as a methyl donor provides labile methyl groups for the synthesis of several metabolically active substances such as creatine and carnitine. Oil in a broiler diet is known to promote a response to dietary betaine supplements, that is, chicks have a higher demand for betaine with a high fat diet. This study implies that betaine supplement may stimulate protection of intestinal epithelium against osmotic disturbance, improve digestion and absorption conditions of the gastrointestinal tract and promote amended use of nutrients.Keywords: heat stress, betaine, performance, broiler‚ growth
Procedia PDF Downloads 59226214 An Investigation of Prior Educational Achievement on Engineering Student Performance
Authors: Jovanca Smith, Derek Gay
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All universities possess a standard by which students are assessed and administered into their programs. This paper considers the effect of the educational history of students, as measured by specific subject grades in Caribbean examinations, on overall performance in introductory engineering math and mechanics courses. Results reflect a correlation between the highest grade in the Caribbean examinations with a higher probability of successful advancement in the university courses. Alternatively, lower entrance grades are commensurate with underperformance in the university courses. Results also demonstrate that students matriculating with the Caribbean examinations will not necessarily possess a significant advantage over students entering through an alternative route, and while previous educational background of students is a significant indicator of tentative performance in the University level math and mechanics courses, it is not the sole factor.Keywords: bimodal distribution, differential learning, engineering education, entrance qualification
Procedia PDF Downloads 36226213 Exfoliation of Functionalized High Structural Integrity Graphene Nanoplatelets at Extremely Low Temperature
Authors: Mohannad N. H. Al-Malichi
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Because of its exceptional properties, graphene has become the most promising nanomaterial for the development of a new generation of advanced materials from battery electrodes to structural composites. However, current methods to meet requirements for the mass production of high-quality graphene are limited by harsh oxidation, high temperatures, and tedious processing steps. To extend the scope of the bulk production of graphene, herein, a facile, reproducible and cost-effective approach has been developed. This involved heating a specific mixture of chemical materials at an extremely low temperature (70 C) for a short period (7 minutes) to exfoliate functionalized graphene platelets with high structural integrity. The obtained graphene platelets have an average thickness of 3.86±0.71 nm and a lateral size less than ~2 µm with a low defect intensity ID/IG ~0.06. The thin film (~2 µm thick) exhibited a low surface resistance of ~0.63 Ω/sq⁻¹, confirming its high electrical conductivity. Additionally, these nanoplatelets were decorated with polar functional groups (epoxy and carboxyl groups), thus have the potential to toughen and provide multifunctional polymer nanocomposites. Moreover, such a simple method can be further exploited for the novel exfoliation of other layered two-dimensional materials such as MXenes.Keywords: functionalized graphene nanoplatelets, high structural integrity graphene, low temperature exfoliation of graphene, functional graphene platelets
Procedia PDF Downloads 12026212 Analysis on the Building Energy Performance of a Retrofitted Residential Building with RETScreen Expert Software
Authors: Abdulhameed Babatunde Owolabi, Benyoh Emmanuel Kigha Nsafon, Jeung-Soo Huh
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Energy efficiency measures for residential buildings in South Korea is a national issue because most of the apartments built in the last decades were constructed without proper energy efficiency measures making the energy performance of old buildings to be very poor when compared with new buildings. However, the adoption of advanced building technologies and regulatory building codes are effective energy efficiency strategies for new construction. There is a need to retrofits the existing building using energy conservation measures (ECMs) equipment’s in order to conserve energy and reduce GHGs emissions. To achieve this, the Institute for Global Climate Change and Energy (IGCCE), Kyungpook National University (KNU), Daegu, South Korea employed RETScreen Expert software to carry out measurement and verification (M&V) analysis on an existing building in Korea by using six years gas consumption data collected from Daesung Energy Co., Ltd in order to determine the building energy performance after the introduction of ECM. Through the M&V, energy efficiency is attained, and the resident doubt was reduced. From the analysis, a total of 657 Giga Joules (GJ) of liquefied natural gas (LNG) was consumed at the rate of 0.34 GJ/day having a peak in the year 2015, which cost the occupant the sum of $10,821.Keywords: energy efficiency, measurement and verification, performance analysis, RETScreen experts
Procedia PDF Downloads 13926211 A Mixed-Method Exploration of the Interrelationship between Corporate Governance and Firm Performance
Authors: Chen Xiatong
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The study aims to explore the interrelationship between corporate governance factors and firm performance in Mainland China using a mixed-method approach. To clarify the current effectiveness of corporate governance, uncover the complex interrelationships between governance factors and firm performance, and enhance understanding of corporate governance strategies in Mainland China. The research involves quantitative methods like statistical analysis of governance factors and firm performance data, as well as qualitative approaches including policy research, case studies, and interviews with staff members. The study aims to reveal the current effectiveness of corporate governance in Mainland China, identify complex interrelationships between governance factors and firm performance, and provide suggestions for companies to enhance their governance practices. The research contributes to enriching the literature on corporate governance by providing insights into the effectiveness of governance practices in Mainland China and offering suggestions for improvement. Quantitative data will be gathered through surveys and sampling methods, focusing on governance factors and firm performance indicators. Qualitative data will be collected through policy research, case studies, and interviews with staff members. Quantitative data will be analyzed using statistical, mathematical, and computational techniques. Qualitative data will be analyzed through thematic analysis and interpretation of policy documents, case study findings, and interview responses. The study addresses the effectiveness of corporate governance in Mainland China, the interrelationship between governance factors and firm performance, and staff members' perceptions of corporate governance strategies. The research aims to enhance understanding of corporate governance effectiveness, enrich the literature on governance practices, and contribute to the field of business management and human resources management in Mainland China.Keywords: corporate governance, business management, human resources management, board of directors
Procedia PDF Downloads 5526210 High Temperature Properties of Diffusion Brazed Joints of in 939 Ni-Base Superalloy
Authors: Hyunki Kang, Hi Won Jeong
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The gas turbine operates for a long period of time under harsh, cyclic conditions of high temperature and pressure, where high turbine inlet temperature (TIT) can range from 1273 to 1873K. Therefore, Ni-base superalloys such as IN738, IN939, Rene 45, Rene 71, Rene 80, Mar M 247, CM 247, and CMSX-4 with excellent mechanical properties and resistance to creep, corrosion and oxidation at high temperatures are indeed used. Among the alloying additions for these alloys, aluminum (Al) and titanium (Ti) form gamma prime and enhance the high-temperature properties. However, when crack-damaged high-temperature turbine components such as blade and vane are repaired by fusion welding, they cause cracks. For example, when arc welding is applied to certain superalloys that contain Al and Ti with more than 3 wt.% and T3.5 wt%, respectively, such as IN738, IN939, Rene 80, Mar M 247, and CM 247, aging cracks occur. Therefore, repair technologies using diffusion brazing, which has less heat input into the base material, are being developed. Analysis of microstructural evolution of the brazed joints with a base metal of IN 939 Ni-base superalloy using brazing different filler metals was also carried out using X-ray diffraction, OEM, SEM-EDS, and EPMA. Stress rupture and high-temperature tensile strength properties were also measured to analyze the effects of different brazing heat cycles. The boron amount in the diffusion-affected zone (DAZ) was decreased towards the base metal and the formation of borides at grain boundaries was detected through EPMA.Keywords: gas turbine, diffusion brazing, superalloy, gas turbine repair
Procedia PDF Downloads 4026209 Effect of Media Reputation on Financial Performance and Abnormal Returns of Corporate Social Responsibility Winner
Authors: Yu-Chen Wei, Dan-Leng Wang
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This study examines whether the reputation from media press affect the financial performance and market abnormal returns around the announcement of corporate social responsibility (CSR) award in the Taiwan Stock Market. The differences between this study and prior literatures are that the media reputation of media coverage and net optimism are constructed by using content analyses. The empirical results show the corporation which won CSR awards could promote financial performance next year. The media coverage and net optimism related to CSR winner are higher than the non-CSR companies prior and after the CSR award is announced, and the differences are significant, but the difference would decrease when the day was closing to announcement. We propose that non-CSR companies may try to manipulate media press to increase the coverage and positive image received by investors compared to the CSR winners. The cumulative real returns and abnormal returns of CSR winners did not significantly higher than the non-CSR samples however the leading returns of CSR winners would higher after the award announcement two months. The comparisons of performances between CSR and non-CSR companies could be the consideration of portfolio management for mutual funds and investors.Keywords: corporate social responsibility, financial performance, abnormal returns, media, reputation management
Procedia PDF Downloads 43426208 Induced Affectivity and Impact on Creativity: Personal Growth and Perceived Adjustment when Narrating an Intense Emotional Experience
Authors: S. Da Costa, D. Páez, F. Sánchez
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We examine the causal role of positive affect on creativity, the association of creativity or innovation in the ideation phase with functional emotional regulation, successful adjustment to stress and dispositional emotional creativity, as well as the predictive role of creativity for positive emotions and social adjustment. The study examines the effects of modification of positive affect on creativity. Participants write three poems, narrate an infatuation episode, answer a scale of personal growth after this episode and perform a creativity task, answer a flow scale after creativity task and fill a dispositional emotional creativity scale. High and low positive effect was induced by asking subjects to write three poems about high and low positive connotation stimuli. In a neutral condition, tasks were performed without previous affect induction. Subjects on the condition of high positive affect report more positive and less negative emotions, more personal growth (effect size r = .24) and their last poem was rated as more original by judges (effect size r = .33). Mediational analysis showed that positive emotions explain the influence of the manipulation on personal growth - positive affect correlates r = .33 to personal growth. The emotional creativity scale correlated to creativity scores of the creative task (r = .14), to the creativity of the narration of the infatuation episode (r = .21). Emotional creativity was also associated, during performing the creativity task, with flow (r = .27) and with affect balance (r = .26). The mediational analysis showed that emotional creativity predicts flow through positive affect. Results suggest that innovation in the phase of ideation is associated with a positive affect balance and satisfactory performance, as well as dispositional emotional creativity is adaptive.Keywords: affectivity, creativity, induction, innovation, psychological factors
Procedia PDF Downloads 11026207 Performance Evaluation of Hierarchical Location-Based Services Coupled to the Greedy Perimeter Stateless Routing Protocol for Wireless Sensor Networks
Authors: Rania Khadim, Mohammed Erritali, Abdelhakim Maaden
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Nowadays Wireless Sensor Networks have attracted worldwide research and industrial interest, because they can be applied in various areas. Geographic routing protocols are very suitable to those networks because they use location information when they need to route packets. Obviously, location information is maintained by Location-Based Services provided by network nodes in a distributed way. In this paper we choose to evaluate the performance of two hierarchical rendezvous location based-services, GLS (Grid Location Service) and HLS (Hierarchical Location Service) coupled to the GPSR routing protocol (Greedy Perimeter Stateless Routing) for Wireless Sensor Network. The simulations were performed using NS2 simulator to evaluate the performance and power of the two services in term of location overhead, the request travel time (RTT) and the query Success ratio (QSR). This work presents also a new scalability performance study of both GLS and HLS, specifically, what happens if the number of nodes N increases. The study will focus on three qualitative metrics: The location maintenance cost, the location query cost and the storage cost.Keywords: location based-services, routing protocols, scalability, wireless sensor networks
Procedia PDF Downloads 37226206 Corruption and Economic Performance in Nigeria: The Role of Forensic Accounting
Authors: Jamila Garba Audu, Peter Adamu
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This study investigates the role of forensic accounting in the fight against corruption in Nigeria for better utilization of public funds and economic growth and development of the Country. We adopted a trend analysis to show the performance of the Nigerian economy as well as the quality of institutions which government economic and political activities in the country. It is an established fact that Nigeria has performed badly since the 1960s to date in terms of institutional quality and economic development despite large amount of money obtained from the export of crude oil. It was revealed also that the fight against corruption has not been very successful in recent times because experts in the field of forensic accounting have not been utilized. With the successes recorded in dealing with fraud and embezzlement using forensic accounting, it has become imperative for the EFCC to use forensic accountants in the fight against corruption in the country. Also, there is the need to introduce very seriously, the teaching of forensic accounting in Nigerian Universities to train experts.Keywords: corruption, economic performance, forensic accounting, Nigeria
Procedia PDF Downloads 37626205 Design-Analysis and Optimization of 10 MW Permanent Magnet Surface Mounted Off-Shore Wind Generator
Authors: Mamidi Ramakrishna Rao, Jagdish Mamidi
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With advancing technology, the market environment for wind power generation systems has become highly competitive. The industry has been moving towards higher wind generator power ratings, in particular, off-shore generator ratings. Current off-shore wind turbine generators are in the power range of 10 to 12 MW. Unlike traditional induction motors, slow-speed permanent magnet surface mounted (PMSM) high-power generators are relatively challenging and designed differently. In this paper, PMSM generator design features have been discussed and analysed. The focus attention is on armature windings, harmonics, and permanent magnet. For the power ratings under consideration, the generator air-gap diameters are in the range of 8 to 10 meters, and active material weigh ~60 tons and above. Therefore, material weight becomes one of the critical parameters. Particle Swarm Optimization (PSO) technique is used for weight reduction and performance improvement. Four independent variables have been considered, which are air gap diameter, stack length, magnet thickness, and winding current density. To account for core and teeth saturation, preventing demagnetization effects due to short circuit armature currents, and maintaining minimum efficiency, suitable penalty functions have been applied. To check for performance satisfaction, a detailed analysis and 2D flux plotting are done for the optimized design.Keywords: offshore wind generator, PMSM, PSO optimization, design optimization
Procedia PDF Downloads 15526204 Effects of Dietary Synbiotics on Growth Performance, Antioxidant Capacity, Digestibility and Intestinal Health of Nile Tilapia (Oreochromis Niloticus)
Authors: Addise Kerebih Chekol
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Current aquaculture practice is sustainable, environment friendly and produces safe products to end users. However, the disease becomes a limitation to the above-mentioned aquaculture practices. Excessive use of antibiotics and chemotherapeutics is practiced in aquaculture health management. The implication of excessive use of antibiotics leads to increasing antibiotic resistance cases among pathogenic bacteria from aquaculture sites and seeping into the food chain. Last but not least, cost is another key determinant for the applicability of the product. In fact, animal feed is one of the main expenditures in aquaculture, which typically accounts for more than 60% of the total expenditure in a fish farm. The intricate production method and the extensive research needed to validate treatment efficacy require sufficient funding. Therefore, the production of cost-effective yet high-quality feed has been a primary agenda for the industry. Therefore, plant herbal could be promising supplements added to fortify the existing animal feed attributed to their multiple potentials in promoting growth, strengthening immunity, and increasing the resistance of animals towards diseases and stresses. Thus, alternative methods in aquaculture species health management should be applied instantly. So, the aim of this study is to determine the effects of dietary synbiotics on growth performance, immunity, and intestinal health of aquatic animals.Keywords: synbiotics, probiotics, prebiotics, Nile Tilapia
Procedia PDF Downloads 1026203 Impact of Legs Geometry on the Efficiency of Thermoelectric Devices
Authors: Angel Fabian Mijangos, Jaime Alvarez Quintana
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Key concepts like waste heat recycling or waste heat recovery are the basic ideas in thermoelectricity so as to the design the newest solid state sources of energy for a stable supply of electricity and environmental protection. According to several theoretical predictions; at device level, the geometry and configuration of the thermoelectric legs are crucial in the thermoelectric performance of the thermoelectric modules. Thus, in this work, it has studied the geometry effect of legs on the thermoelectric figure of merit ZT of the device. First, asymmetrical legs are proposed in order to reduce the overall thermal conductance of the device so as to increase the temperature gradient in the legs, as well as by harnessing the Thomson effect, which is generally neglected in conventional symmetrical thermoelectric legs. It has been developed a novel design of a thermoelectric module having asymmetrical legs, and by first time it has been validated experimentally its thermoelectric performance by realizing a proof-of-concept device which shows to have almost twofold the thermoelectric figure of merit as compared to conventional one. Moreover, it has been also varied the length of thermoelectric legs in order to analyze its effect on the thermoelectric performance of the device. Along with this, it has studied the impact of contact resistance in these systems. Experimental results show that device architecture can improve up to twofold the thermoelectric performance of the device.Keywords: asymmetrical legs, heat recovery, heat recycling, thermoelectric module, Thompson effect
Procedia PDF Downloads 24126202 Development and Characterization of Biscuits Incorporated with Jackfruit (Artocarpus heterophyllus) Seeds and Cassava (Manihot esculenta)
Authors: Elina Brahma Hazarika, Jeuti Basumatary, Deepanka Saikia, Jaydeep Das, Micky Moni D'mary, Fungkha Basumatary
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This study includes development of two varieties of biscuits incorporated with: the seeds of Jack fruit (Artocarpus heterophyllus), which post-consumption of it’s pulp, is discarded as a waste, and Cassava (Manihot esculenta) tubers.The jack fruit seeds and cassava were first ground into flour and its proximate and physiochemical properties were studied. The biscuits that were developed incorporating them had 50% wheat flour and 50% jackfruit seed flour and 50% cassava flours as the major composition, apart from the other general ingredients use in making biscuits. Various trials of compositions were made for baking to get the overall desirable acceptability in biscuits through sensory evaluation. Finally, the best composition of ingredients was selected to make the biscuits, and hence studies were done accordingly to compare it with the properties of their respective raw flours. The results showed that the proximate composition of the biscuits fared better than that of their respective flours: There was a decrease in the Moisture content of both Jackfruit Seed Biscuits and Cassava Biscuits to 4.5% and 6.7% than that of their respective raw flours (8 and 12%). Post-baking, there is increase in the percentages of ash, protein, and fibre contents in both Jackfruit Seed Biscuits and Cassava Biscuits; the values being 3% and 3.8%, 13.2% and 3.3%, and 3.2 and 4.1% respectively. Also the total carbohydrate content in Jackfruit Seed Biscuits and Cassava Biscuits were 66.7% and 71.7% respectively. Their sensory evaluation and texture study also yielded a clear review that they have an overall good acceptability.Keywords: baking, proximate, sensory, texture
Procedia PDF Downloads 32026201 Wrist Pain, Technological Device Used, and Perceived Academic Performance Among the College of Computer Studies Students
Authors: Maquiling Jhuvie Jane R., Ojastro Regine B., Peroja Loreille Marie B., Pinili Joy Angela., Salve Genial Gail M., Villavicencio Marielle Irene B., Yap Alther Francis Garth B.
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Introduction: This study investigated the impact of prolonged device usage on wrist pain and perceived academic performance among college students in Computer Studies. The research aims to explore the correlation between the frequency of technological device use and the incidence of wrist pain, as well as how this pain affects students' academic performance. The study seeks to provide insights that could inform interventions to promote better musculoskeletal health among students engaged in intensive technology use to further improve their academic performance. Method: The study utilized descriptive-correlational and comparative design, focusing on bona fide students from Silliman University’s College of Computer Studies during the second semester of 2023-2024. Participants were recruited through a survey sent via school email, with responses collected until March 30, 2024. Data was gathered using a password-protected device and Google Forms, ensuring restricted access to raw data. The demographic profile was summarized, and the prevalence of wrist pain and device usage were analyzed using percentages and weighted means. Statistical analyses included Spearman’s rank correlation coefficient to assess the relationship between wrist pain and device usage and an Independent T-test to evaluate differences in academic performance based on wrist pain presence. Alpha was set at 0.05. Results: The study revealed that 40% of College of Computer Studies students experience wrist pain, with 2 out of every 5 students affected. Laptops and desktops were the most frequently used devices for academic work, achieving a weighted mean of 4.511, while mobile phones and tablets received lower means of 4.183 and 1.911, respectively. The average academic performance score among students was 29.7, classified as ‘Good Performance.’ Notably, there was no significant relationship between the frequency of device usage and wrist pain, as indicated by p-values exceeding 0.05. However, a significant difference in perceived academic performance was observed, with students without wrist pain scoring an average of 30.39 compared to 28.72 for those with wrist pain and a p-value of 0.0134 confirming this distinction. Conclusion: The study revealed that about 40% of students in the College of Computer Studies experience wrist pain, but there is no significant link between device usage and pain occurrence. However, students without wrist pain demonstrated better academic performance than those with pain, suggesting that wrist health may impact academic success. These findings imply that physical therapy practices in the Philippines should focus on preventive strategies and ergonomic education to improve student health and performance.Keywords: wrist pain, frequency of use of technological devices, perceived academic performance, physical therapy
Procedia PDF Downloads 1426200 Implication of Attention Deficit and Task Avoidance on the Mathematics Performance of Pupils with Intellectual Disabilities
Authors: Matthew Bamidele Ojuawo
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To some parents, task avoidance implies the time when argument ensues between parents and their children in order to get certain things done correctly without being forced. However, some children avoid certain task because of the fears that it is too hard or cannot be done without parental help. Laziness plays a role in task avoidance when children do not want to do something because they do not feel like it is easy enough or if they just want their parent help them get it over with more quickly. Children with attention deficit disorder more often have difficulties with social skills, such as social interaction and forming and maintaining friendships. The focus of this study is how task avoidance and attention deficit have effect on the mathematics performance of pupils in the lower basic classroom. Mathematics performance of pupils with learning disabilities has been seriously low due to avoidance of task and attention deficit posed as carried out in the previous researches, but the research has not been carried out in the lower basic classroom in Oyo, Oyo state, Nigeria.Keywords: task avoidance, parents, children with attention deficit, mathematics
Procedia PDF Downloads 14326199 A Method for Quantifying Arsenolipids in Sea Water by HPLC-High Resolution Mass Spectrometry
Authors: Muslim Khan, Kenneth B. Jensen, Kevin A. Francesconi
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Trace amounts (ca 1 µg/L, 13 nM) of arsenic are present in sea water mostly as the oxyanion arsenate. In contrast, arsenic is present in marine biota (animals and algae) at very high levels (up to100,000 µg/kg) a significant portion of which is present as lipid-soluble compounds collectively termed arsenolipids. The complex nature of sea water presents an analytical challenge to detect trace compounds and monitor their environmental path. We developed a simple method using liquid-liquid extraction combined with HPLC-High Resolution Mass Spectrometer capable of detecting trace of arsenolipids (99 % of the sample matrix while recovering > 80 % of the six target arsenolipids with limit of detection of 0.003 µg/L.)Keywords: arsenolipids, sea water, HPLC-high resolution mass spectrometry
Procedia PDF Downloads 36626198 Performance of an Optical Readout Gas Chamber for Charged Particle Track
Authors: Jing Hu, Xiaoping Ouyang
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We develop an optical readout gas chamber based on avalanche-induced scintillation for energetic charged particles track. The gas chamber is equipped with a Single Anode Wires (SAW) structure to produce intensive electric field when the measured particles are of low yield or even single. In the presence of an intensive electric field around the single anode, primary electrons, resulting from the incident charged particles when depositing the energy along the track, accelerate to the anode effectively and rapidly. For scintillation gasses, this avalanche of electrons induces multiplying photons comparing with the primary scintillation excited directly from particle energy loss. The electric field distribution for different shape of the SAW structure is analyzed, and finally, an optimal one is used to study the optical readout performance. Using CF4 gas and its mixture with the noble gas, the results indicate that the optical readout characteristics of the chamber are attractive for imaging. Moreover, images of particles track including single particle track from 5.485MeV alpha particles are successfully acquired. The track resolution is quite well for the reason that the electrons undergo less diffusion in the intensive electric field. With the simple and ingenious design, the optical readout gas chamber has a high sensitivity. Since neutrons can be converted to charged particles when scattering, this optical readout gas chamber can be applied to neutron measurement for dark matter, fusion research, and others.Keywords: optical readout, gas chamber, charged particle track, avalanche-induced scintillation, neutron measurement
Procedia PDF Downloads 27226197 Green Intellectual Capital and Green Supply Chain Performance
Authors: Mohammed Ibrahim Bu Haya, Abdelmoneim Bahyeldin Mohamed Metwally
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This paper examines the impact of Green Intellectual Capital (GIC) on Green Supply Chain Performance (GSCP). Further, the study examines the moderating role of external pressures (EP) on the relationship between GIC and GSCP. Data were collected from employees working in Egyptian hotels and tourism companies (N= 366). The collected data were analyzed using smart partial least squares (Smart-PLS) software. The current research indicated that there is a positive and significant impact of all GIC components on GSCP. The results also revealed that EP were found to moderate the relationship between GIC and GSCP. The study model was able to explain 63.1% of the variance in GSCP. The findings of this study serve as a pivotal yardstick for guiding corporate policy formulation, offering valuable insights to drive continuous improvements in supply chain management and performance. Furthermore, the research holds substantial implications for managerial strategies by shedding light on the potential of GIC and EP to elevate GSCP. Positioned as one of the initial studies to delve into the moderating role of EP in the relationship between GIC and GSCP, this research offers insights within an emerging market context.Keywords: green intellectual capital, green supply chain, supply chain performance, external pressures, emerging economy, Egypt
Procedia PDF Downloads 5626196 Supply Chain Logistics Integration in Bahrain's Construction Industry
Authors: Randolf Von N. Salindo
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The study was conducted to measure the logistics integration capabilities of selected companies in the Bahrain construction industry using the Supply Chain 2000 framework; and, determine the extent and direction of influence of these logistics capabilities and integration competencies on the supply chain performance of the firm. A total of 50 executive respondents (from supervisor to managing director level) from 22 construction and construction supplier firms participated in the study from September to November 2014. The results reveal that respondent Bahraini construction firms have significantly lower levels of logistics capabilities, but higher levels of logistics integration competencies compared to international benchmarks. Using stepwise multiple regression analysis, eight logistics capabilities of Bahraini constructions firms were identified to be positively associated with firm performance; with comprehensive metrics as the most positively dominant influential logistics capability. Activity based and total cost methodology is found to be the most negatively dominant influential logistics capability. In terms of logistics integration competencies, the study revealed that that customer integration, internal integration, and, measurement integration are negatively associated with firm performance. There was no logistics integration competency found to be positively associated with the supply chain performance among the companies who participated in the study. The research reveals that there are areas for improvement in supply chain capabilities and logistics integration competencies of the construction firms in the Kingdom of Bahrain to improve their supply chain performance to a global level.Keywords: comprehensive metrics, customer integration, logistics integration capabilities, logistics integration competencies
Procedia PDF Downloads 64226195 Application of Water Soluble Polymers in Chemical Enhanced Oil Recovery
Authors: M. Shahzad Kamal, Abdullah S. Sultan, Usamah A. Al-Mubaiyedh, Ibnelwaleed A. Hussein
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Oil recovery from reservoirs using conventional oil recovery techniques like water flooding is less than 20%. Enhanced oil recovery (EOR) techniques are applied to recover additional oil. Surfactant-polymer flooding is a promising EOR technique used to recover residual oil from reservoirs. Water soluble polymers are used to increase the viscosity of displacing fluids. Surfactants increase the capillary number by reducing the interfacial tension between oil and displacing fluid. Hydrolyzed polyacrylamide (HPAM) is widely used in polymer flooding applications due to its low cost and other desirable properties. HPAM works well in low-temperature and low salinity-environment. In the presence of salts HPAM viscosity decrease due to charge screening effect and it can precipitate at high temperatures in the presence of salts. Various strategies have been adopted to extend the application of water soluble polymers to high-temperature high-salinity (HTHS) reservoir. These include addition of monomers to acrylamide chain that can protect it against thermal hydrolysis. In this work, rheological properties of various water soluble polymers were investigated to find out suitable polymer and surfactant-polymer systems for HTHS reservoirs. Polymer concentration ranged from 0.1 to 1 % (w/v). Effect of temperature, salinity and polymer concentration was investigated using both steady shear and dynamic measurements. Acrylamido tertiary butyl sulfonate based copolymer showed better performance under HTHS conditions compared to HPAM. Moreover, thermoviscosifying polymer showed excellent rheological properties and increase in the viscosity was observed with increase temperature. This property is highly desirable for EOR application.Keywords: rheology, polyacrylamide, salinity, enhanced oil recovery, polymer flooding
Procedia PDF Downloads 41126194 An Experimental Study on the Thermal Properties of Concrete Aggregates in Relation to Their Mineral Composition
Authors: Kyung Suk Cho, Heung Youl Kim
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The analysis of the petrologic characteristics and thermal properties of crushed aggregates for concrete such as granite, gneiss, dolomite, shale and andesite found that rock-forming minerals decided the thermal properties of the aggregates. The thermal expansion coefficients of aggregates containing lots of quartz increased rapidly at 573 degrees due to quartz transition. The mass of aggregate containing carbonate minerals decreased rapidly at 750 degrees due to decarboxylation, while its specific heat capacity increased relatively. The mass of aggregates containing hydrated silicate minerals decreased more significantly, and their specific heat capacities were greater when compared with aggregates containing feldspar or quartz. It is deduced that the hydroxyl group (OH) in hydrated silicate dissolved as its bond became loose at high temperatures. Aggregates containing mafic minerals turned red at high temperatures due to oxidation response. Moreover, the comparison of cooling methods showed that rapid cooling using water resulted in more reduction in aggregate mass than slow cooling at room temperatures. In order to observe the fire resistance performance of concrete composed of the identical but coarse aggregate, mass loss and compressive strength reduction factor at 200, 400, 600 and 800 degrees were measured. It was found from the analysis of granite and gneiss that the difference in thermal expansion coefficients between cement paste and aggregates caused by quartz transit at 573 degrees resulted in thermal stress inside the concrete and thus triggered concrete cracking. The ferromagnesian hydrated silicate in andesite and shale caused greater reduction in both initial stiffness and mass compared with other aggregates. However, the thermal expansion coefficient of andesite and shale was similar to that of cement paste. Since they were low in thermal conductivity and high in specific heat capacity, concrete cracking was relatively less severe. Being slow in heat transfer, they were judged to be materials of high heat capacity.Keywords: crush-aggregates, fire resistance, thermal expansion, heat transfer
Procedia PDF Downloads 22826193 Impact of National Institutions on Corporate Social Performance
Authors: Debdatta Mukherjee, Abhiman Das, Amit Garg
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In recent years, there is a growing interest about corporate social responsibility of firms in both academic literature and business world. Since business forms a part of society incorporating socio-environment concerns into its value chain, activities are vital for ensuring mutual sustainability and prosperity. But, until now most of the works have been either descriptive or normative rather than positivist in tone. Even the few ones with a positivist approach have mostly studied the link between corporate financial performance and corporate social performance. However, these studies have been severely criticized by many eminent authors on grounds that they lack a theoretical basis for their findings. They have also argued that apart from corporate financial performance, there must be certain other crucial influences that are likely to determine corporate social performance of firms. In fact, several studies have indicated that firms operating in distinct national institutions show significant variations in the corporate social responsibility practices that they undertake. This clearly suggests that the institutional context of a country in which the firms operate is a key determinant of corporate social performance of firms. Therefore, this paper uses an institutional framework to understand why corporate social performance of firms vary across countries. It examines the impact of country level institutions on corporate social performance using a sample of 3240 global publicly-held firms across 33 countries covering the period 2010-2015. The country level institutions include public institutions, private institutions, markets and capacity to innovate. Econometric Analysis has been mainly used to assess this impact. A three way panel data analysis using fixed effects has been used to test and validate appropriate hypotheses. Most of the empirical findings confirm our hypotheses and the economic significance indicates the specific impact of each variable and their importance relative to others. The results suggest that institutional determinants like ethical behavior of private institutions, goods market, labor market and innovation capacity of a country are significantly related to the corporate social performance of firms. Based on our findings, few implications for policy makers from across the world have also been suggested. The institutions in a country should promote competition. The government should use policy levers for upgrading home demands, like setting challenging yet flexible safety, quality and environment standards, and framing policies governing buyer information, providing innovative recourses to low quality goods and services and promoting early adoption of new and technologically advanced products. Moreover, the institution building in a country should be such that they facilitate and improve the capacity of firms to innovate. Therefore, the proposed study argues that country level institutions impact corporate social performance of firms, empirically validates the same, suggest policy implications and attempts to contribute to an extended understanding of corporate social responsibility and corporate social performance in a multinational context.Keywords: corporate social performance, corporate social responsibility, institutions, markets
Procedia PDF Downloads 16626192 Color Conversion Films with CuInS2/ZnS Quantum Dots Embedded Polystyrene Nanofibers by Electrospinning Process
Authors: Wonkyung Na, Namhun Kim, Heeyeop Chae
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Quantum dots (QDs) are getting attentions due to their excellent optical properties in display, solar cell, biomolecule detection and lighting applications. Energy band gap can be easilty controlled by controlling their size and QDs are proper to apply in light-emitting-diode(LED) and lighting application, especially. Typically cadmium (Cd) containing QDs show a narrow photoluminescence (PL) spectrum and high quantum yield. However, Cd is classified as a hazardous materials and the use of Cd is being tightly regulated under 100ppm level in many countries.InP and CuInS2 (CIS) are being investigated as Cd-free QD materials and it is recently demonstrated that the performance of those Cd-free QDs is comparable to their Cd-based rivals.Due to a broad emission spectrum, CuInS2 QDs are also proper to be applied to white LED.4 For the lighting applications, the QD should be made in forms of color conversion films. Various film processes are reported with QDs in polymer matrixes. In this work, we synthesized the CuInS2 (CIS) QDs and QD embedded polystyrene color conversion films were fabricated for white color emission with electro-spinning process. As a result, blue light from blue LED is converted to white light with high color rendering index (CRI) of 72 by the color conversion films.Keywords: CuInS2/ZnS, electro-spinning, color conversion films, white light emitting diodes
Procedia PDF Downloads 813