Search results for: critical energy level
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 24049

Search results for: critical energy level

20149 Advanced Energy Absorbers Used in Blast Resistant Systems

Authors: Martina Drdlová, Michal Frank, Radek Řídký, Jaroslav Buchar, Josef Krátký

Abstract:

The main aim of the presented experiments is to improve behaviour of sandwich structures under dynamic loading, such as crash or explosion. This paper describes experimental investigation on the response of new advanced materials to low and high velocity load. Blast wave energy absorbers were designed using two types of porous lightweight raw particle materials based on expanded glass and ceramics with dimensions of 0.5-1 mm, combined with polymeric binder. The effect of binder amount on the static and dynamic properties of designed materials was observed. Prism shaped specimens were prepared and loaded to obtain physico-mechanical parameters – bulk density, compressive and flexural strength under quasistatic load, the dynamic response was determined using Split Hopkinson Pressure bar apparatus. Numerical investigation of the material behaviour in sandwich structure was performed using implicit/explicit solver LS-Dyna. As the last step, the developed material was used as the interlayer of blast resistant litter bin, and it´s functionality was verified by real field blast tests.

Keywords: blast energy absorber, SHPB, expanded glass, expanded ceramics

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20148 Molecular Characterization of Arginine Sensing Response in Unravelling Host-Pathogen Interactions in Leishmania

Authors: Evanka Madan, Madhu Puri, Dan Zilberstein, Rohini Muthuswami, Rentala Madhubala

Abstract:

The extensive interaction between the host and pathogen metabolic networks decidedly shapes the outcome of infection. Utilization of arginine by the host and pathogen is critical for determining the outcome of pathogenic infection. Infections with L. donovani, an intracellular parasite, will lead to an extensive competition of arginine between the host and the parasite donovani infection. One of the major amino acid (AA) sensing signaling pathways in mammalian cells are the mammalian target of rapamycin complex I (mTORC1) pathway. mTORC1, as a sensor of nutrient, controls numerous metabolic pathways. Arginine is critical for mTORC1 activation. SLC38A9 is the arginine sensor for the mTORC1, being activated during arginine sufficiency. L. donovani transport arginine via a high-affinity transporter (LdAAP3) that is rapidly up-regulated by arginine deficiency response (ADR) in intracellular amastigotes. This study, to author’s best knowledge, investigates the interaction between two arginine sensing systems that act in the same compartment, the lysosome. One is important for macrophage defense, and the other is essential for pathogen virulence. We hypothesize that the latter modulates lysosome arginine to prevent host defense response. The work presented here identifies an upstream regulatory role of LdAAP3 in regulating the expression of SLC38A9-mTORC1 pathway, and consequently, their function in L. donovani infected THP-1 cells cultured in 0.1 mM and 1.5 mM arginine. It was found that in physiological levels of arginine (0.1 mM), infecting THP-1 with Leishmania leads to increased levels of SLC38A9 and mTORC1 via an increase in the expression of RagA. However, the reversal was observed with LdAAP3 mutants, reflecting the positive regulatory role of LdAAP3 on the host SLC38A9. At the molecular level, upon infection, mTORC1 and RagA were found to be activated at the surface of phagolysosomes which was found to form a complex with phagolysosomal localized SLC38A9. To reveal the relevance of SLC38A9 under physiological levels of arginine, endogenous SLC38A9 was depleted and a substantial reduction in the expression of host mTORC1, its downstream active substrate, p-P70S6K1 and parasite LdAAP3, was observed, thereby showing that silencing SLC38A9 suppresses ADR. In brief, to author’s best knowledge, these results reveal an upstream regulatory role of LdAAP3 in manipulating SLC38A9 arginine sensing in host macrophages. Our study indicates that intra-macrophage survival of L. donovani depends on the availability and transport of extracellular arginine. An understanding of the sensing pathway of both parasite and host will open a new perspective on the molecular mechanism of host-parasite interaction and consequently, as a treatment for Leishmaniasis.

Keywords: arginine sensing, LdAAP3, L. donovani, mTORC1, SLC38A9, THP-1

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20147 Polymer Nanostructures Based Catalytic Materials for Energy and Environmental Applications

Authors: S. Ghosh, L. Ramos, A. N. Kouamé, A.-L. Teillout, H. Remita

Abstract:

Catalytic materials have attracted continuous attention due to their promising applications in a variety of energy and environmental applications including clean energy, energy conversion and storage, purification and separation, degradation of pollutants and electrochemical reactions etc. With the advanced synthetic technologies, polymer nanostructures and nanocomposites can be directly synthesized through soft template mediated approach using swollen hexagonal mesophases and modulate the size, morphology, and structure of polymer nanostructures. As an alternative to conventional catalytic materials, one-dimensional PDPB polymer nanostructures shows high photocatalytic activity under visible light for the degradation of pollutants. These photocatalysts are very stable with cycling. Transmission electron microscopy (TEM), and AFM-IR characterizations reveal that the morphology and structure of the polymer nanostructures do not change after photocatalysis. These stable and cheap polymer nanofibers and metal polymer nanocomposites are easy to process and can be reused without appreciable loss of activity. The polymer nanocomposites formed via one pot chemical redox reaction with 3.4 nm Pd nanoparticles on poly(diphenylbutadiyne) (PDPB) nanofibers (30 nm). The reduction of Pd (II) ions is accompanied by oxidative polymerization leading to composites materials. Hybrid Pd/PDPB nanocomposites used as electrode materials for the electrocatalytic oxidation of ethanol without using support of proton exchange Nafion membrane. Hence, these conducting polymer nanofibers and nanocomposites offer the perspective of developing a new generation of efficient photocatalysts for environmental protection and in electrocatalysis for fuel cell applications.

Keywords: conducting polymer, swollen hexagonal mesophases, solar photocatalysis, electrocatalysis, water depollution

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20146 Adaptive Approach Towards Comprehensive Urban Development Simulation in Coastal Regions: Case Study of New Alamein City, Egypt

Authors: Nada Mohamed, Abdel Aziz Mohamed

Abstract:

Climate change in coastal areas is a global issue that can be felt on local scale and will be around for decades and centuries to come to an end; it also has critical risks on the city’s economy, communities, and the natural environment. One of these changes that cause a huge risk on coastal cities is the sea level rise (SLR). SLR is a result of scarcity and reduction in global environmental system. The main cause of climate change and global warming is the countries with high development index (HDI) as Japan and Germany while the medium and low HDI countries as Egypt does not have enough awareness and advanced tactics to adapt with this changes that destroy urban areas and cause loss in land and economy. This is why Climate Resilience is one of the UN sustainable development goals 2030, which is calling for actions to strengthen climate change resilience through mitigation and adaptation. For many reasons, adaptation has received less attention than mitigation and it is only recently that adaptation has become a focal global point of attention. This adaption can be achieved through some actions such as upgrading the use and the design of the land, adjusting business and activities of people, and increasing community understanding of climate risks. To reach the adaption goals, and we have to apply a strategic pathway to Climate Resilience, which is the Urban Bioregionalism Paradigm. Resiliency has been framed as persistence, adaptation, and transformation. Climate Resilience decision support system includes a visualization platform where ecological, social, and economic information can be viewed alongside with specific geographies that's why Urban Bioregionalism is a socio-ecological system which is defined as a paradigm that has potential to help move social attitudes toward environmental understanding and deepen human-environment connections within ecological development. The research aim is to achieve an adaptive integrated urban development model throughout the analyses of tactics and strategies that can be used to adapt urban areas and coastal communities to the challenges of climate changes especially SLR and also simulation model using advanced technological software for a coastal city corridor to elaborates the suitable strategy to apply.

Keywords: climate resilience, sea level rise, SLR, coastal resilience, adaptive development simulation

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20145 Antidiabetic Effect of Aqueous Extract of Cedrus deodara Roxb. Heartwood in Alloxan-Induced Diabetic Rats

Authors: Sourabh Jain, Vikas Jain, Dharmendar Kumar

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The present study investigated the antidiabetic potential of Cedrus deodara heart wood aqueous extract. Aqueous extract of Cedrus deodara was found to reduce blood sugar level in alloxan induced diabetic rats. Reduction in blood sugar could be seen from 5th day after continuous administration of the extract and on 21st day sugar levels were found to be reduced by 40.20%. Oxidative stress produced by alloxan was found to be significantly lowered by the administration of Cedrus deodara aqueous extract (500 mg/kg). This was evident from a significant decrease in lipid per oxidation level in liver induced by alloxan. The level of Glutathione, Catalase, Superoxide dismutase and Glutathione-S-Transferase in liver, kidney and pancreas tissue were found to be increased significantly after drug administration. The results obtained in the present study suggest that the Cedrus deodara aqueous extract effectively and significantly reduced the oxidative stress induced by alloxan and produced a reduction in blood sugar level.

Keywords: Cedrus deodara, heartwood, antioxidant, anti-diabetic, anti-inflammatory

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20144 An Investigation of the University Council’s Image: A Case of Suan Sunandha Rajabhat University

Authors: Phitsanu Phunphetchphan

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The purposes of this research was to investigate opinions of Rajabhat University staff towards performance of the university council committee by focusing on (1) personal characteristics of the committees; (2) duties designated by the university council; and (3) relationship between university council and staff. The population of this study included all high level of management from Suan Sunandha Rajabhat University which made a total of 200 respondents. Data analysis included frequency, percentage, mean and standard deviation. The findings revealed that the majority of staff rated the performance of university council at a high level. The 'overall appropriate qualification of the university council' was rated as the highest score while 'good governance' was rated as the lowest mean score. Moreover, the findings also revealed that the relationship between university council’s members and the staff was rated at a high level while 'the integrity of policy implementation' was rated as the lowest score.

Keywords: investigation, performance, university council, management

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20143 Unveiling the Mystery of Innovation in Higher Education Institutions

Authors: Ana Martins, Isabel Martins

Abstract:

The purpose of this research is to ascertain whether students at HEIs cultivate distributed leadership and higher-level skills to inspire knowledge creation. Critical reflection of extant literature illustrates the need for a culture of innovation in organizational sustainability. New age leadership behaviors harmonize innovation. The leadership self-efficacy construct supports organizational learning. This exploratory study applies the pragmatic paradigm methodology using the survey research method for primary data collection. A questionnaire was distributed to a sample of university students based in the Southern Anatolian region of Turkey, from both under and postgraduate Business degree programs. An analysis of the findings reveals a greater connection in influencing behavior relying more on the task-centered perspective rather than with the people perspective. These results reveal the need for HEIs to instill a humanistic perspective in curricula enabling graduates to be capable leaders with the awareness soft skills to energize creativity and innovation. A limitation of this research is that one university makes it difficult to generalize to a broader population. This study is of added value for scholars and organizations in the current knowledge and innovation economy.

Keywords: distributed leadership, exploration, higher education institutions, innovation, knowledge creation, learning, self-efficacy

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20142 Resource Allocation of Small Agribusinesses and Entrepreneurship Development In Nigeria

Authors: Festus M. Epetimehin

Abstract:

Resources are essential materials required for production of goods and services. Effective allocation of these resources can engender the success of current business activities and its sustainability for future generation. The study examined effect of resource allocation of small agribusinesses on entrepreneurship development in Southwest Nigeria. Sample size of 385 was determined using Cochran’s formula. 350 valid copies of questionnaire were used in the analysis. In order to achieve the objective, research design (descriptive and cross sectional designs) was used to gather data for the study through the administration of questionnaire to respondents. Both descriptive and inferential statistics were used to investigate the objective of the study. The result obtained indicated that resource allocation by small agribusinesses had a substantial positive effect on entrepreneurship development with the p-value of (0.0000) which was less than the 5.0% critical value with a positive regression coefficient of 0.53. The implication of this is that the ability of the entrepreneurs to deploy their resources efficiently through adequate realization of better gross margin could enhance business activities and development. The study recommends that business owners still need some level of serious training and exposure on how to manage modern small agribusiness resources to enhance business performance. The intervention of Agricultural Development Programme (ADP) and other Agricultural institutions are needed in this regard.

Keywords: resource, resource allocation, small businesses, agriculture, entrepreneurship development

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20141 Water and Sanitation Challenges: A Case of King Sabatha Dalindyebo Municipality

Authors: Masibulele Fiko, Sanjay Balkara, Beauty Makiwane, Samson Asoba

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Several municipalities in the Eastern Cape Province of South Africa suffer from severe infrastructure dilapidation and a backlog in repairs and replacement. This scourge is most critical in black dominated areas, such as the rural communities and townships. Several critical service delivery activities have been impaired consequent to the deteriorating facilities and a lot of human endeavors impacted adversely. As such, this study investigated the water and sanitation challenges in King Sabatha Dalindyebo municipality, Eastern Cape Province of South Africa. Questionnaires were distributed to the communities and interviews were conducted with the communities’ leaders. The Participants mentioned that their main sources of water supply were a dam, streams, springs and wells; and the distances to the water sources were thought to be too long and women were often attacked and sometimes raped. South African local authorities are facing problems of insufficient funds to meet their daily operations. The municipality should provide street taps. The alternative way for government to supply financial aid to local authorities is to introduce the private sector in the service rendering process.

Keywords: communities, sanitation, managers, municipality

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20140 Evaluating Reliability Indices in 3 Critical Feeders at Lorestan Electric Power Distribution Company

Authors: Atefeh Pourshafie, Homayoun Bakhtiari

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The main task of power distribution companies is to supply the power required by customers in an acceptable level of quality and reliability. Some key performance indicators for electric power distribution companies are those evaluating the continuity of supply within the network. More than other problems, power outages (due to lightning, flood, fire, earthquake, etc.) challenge economy and business. In addition, end users expect a reliable power supply. Reliability indices are evaluated on an annual basis by the specialized holding company of Tavanir (Power Produce, Transmission& distribution company of Iran) . Evaluation of reliability indices is essential for distribution companies, and with regard to the privatization of distribution companies, it will be of particular importance to evaluate these indices and to plan for their improvement in a not too distant future. According to IEEE-1366 standard, there are too many indices; however, the most common reliability indices include SAIFI, SAIDI and CAIDI. These indices describe the period and frequency of blackouts in the reporting period (annual or any desired timeframe). This paper calculates reliability indices for three sample feeders in Lorestan Electric Power Distribution Company and defines the threshold values in a ten-month period. At the end, strategies are introduced to reach the threshold values in order to increase customers' satisfaction.

Keywords: power, distribution network, reliability, outage

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20139 Advancing Net Zero Showcase in Subtropical High-Rise Commercial Building

Authors: Melody Wong

Abstract:

Taikoo Green Ribbon is the winning scheme of International Advancing Net Zero ANZ Ideas Competition 2021 and shortlisted as a finalist of top Architectural Award “AJ100 Sustainability Initiative of the Year, 2022, demonstrating city's aspirations to reach carbon neutrality by 2050. The project showcases total design solutions to blend technology and nature to create a futuristic workplace achieving net zero within a decade. The net zero building design featured with extremely low embodied carbon emission (<250 kgCO2/sqm), significant surplus in renewable energy generation (130% of energy consumption) and various carbon capture technology. The project leverages aesthetics, user-experience, sustainability, and technology to develop over 40 design features. Utilizing AI-controlled Smart Envelope system, the possibility of naturally ventilation was maximized to adjust the microclimate to foster behavourial change. The design principle – healthy and collaborative working environment is realized with a landscaped sky-track with kinetic energy pads, natural ventilated open space with edible plants across floors, and 500-seat open-space rooftop theatre to reshape and redefine the new generation of workplaces.

Keywords: NetZero, zero carbon, green, sustainability

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20138 Patronage Network and Ideological Manipulations in Translation of Literary Texts: A Case Study of George Orwell's “1984” in Persian Translation in the Period 1980 to 2015

Authors: Masoud Hassanzade Novin, Bahloul Salmani

Abstract:

The process of the translation is not merely the linguistic aspects. It is also considered in the cultural framework of both the source and target text cultures. The translation process and translated texts are confronted the new aspect in 20th century which is considered mostly in the patronage framework and ideological grillwork of the target language. To have these factors scrutinized in the process of the translation both micro-element factors and macro-element factors can be taken into consideration. For the purpose of this study through a qualitative type of research based on critical discourse analysis approach, the case study of the novel “1984” written by George Orwell was chosen as the corpus of the study to have the contrastive analysis by its Persian translated texts. Results of the study revealed some distortions embedded in the target texts which were overshadowed by ideological aspect and patronage network. The outcomes of the manipulated terms were different in various categories which revealed the manipulation aspects in the texts translated.

Keywords: critical discourse analysis, ideology, patronage network, translated texts

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20137 Chairussyuhur Arman, Totti Tjiptosumirat, Muhammad Gunawan, Mastur, Joko Priyono, Baiq Tri Ratna Erawati

Authors: Maria M. Giannakou, Athanasios K. Ziliaskopoulos

Abstract:

Transmission pipelines carrying natural gas are often routed through populated cities, industrial and environmentally sensitive areas. While the need for these networks is unquestionable, there are serious concerns about the risk these lifeline networks pose to the people, to their habitat and to the critical infrastructures, especially in view of natural disasters such as earthquakes. This work presents an Integrated Pipeline Risk Management methodology (IPRM) for assessing the hazard associated with a natural gas pipeline failure due to natural or manmade disasters. IPRM aims to optimize the allocation of the available resources to countermeasures in order to minimize the impacts of pipeline failure to humans, the environment, the infrastructure and the economic activity. A proposed knapsack mathematical programming formulation is introduced that optimally selects the proper mitigation policies based on the estimated cost – benefit ratios. The proposed model is demonstrated with a small numerical example. The vulnerability analysis of these pipelines and the quantification of consequences from such failures can be useful for natural gas industries on deciding which mitigation measures to implement on the existing pipeline networks with the minimum cost in an acceptable level of hazard.

Keywords: cost benefit analysis, knapsack problem, natural gas distribution network, risk management, risk mitigation

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20136 Performances Analysis and Optimization of an Adsorption Solar Cooling System

Authors: Nadia Allouache

Abstract:

The use of solar energy in cooling systems is an interesting alternative to the increasing demand of energy in the world and more specifically in southern countries where the needs of refrigeration and air conditioning are tremendous. This technique is even more attractive with regards to environmental issues. This study focuses on performances analysis and optimization of solar reactor of an adsorption cooling machine working with activated carbon-methanol pair. The modeling of the adsorption cooling machine requires the resolution of the equation describing the energy and mass transfer in the tubular adsorber that is the most important component of the machine. The results show the poor heat conduction inside the porous medium and the resistance between the metallic wall and the bed engender the important temperature gradient and a great difference between the metallic wall and the bed temperature; this is considered as the essential causes decreasing the performances of the machine. For fixed conditions of functioning, the total desorbed mass presents a maximum for an optimal value of the height of the adsorber; this implies the existence of an optimal dimensioning of the adsorber.

Keywords: solar cooling system, performances Analysis, optimization, heat and mass transfer, activated carbon-methanol pair, numerical modeling

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20135 Photovoltaic-Driven Thermochemical Storage for Cooling Applications to Be Integrated in Polynesian Microgrids: Concept and Efficiency Study

Authors: Franco Ferrucci, Driss Stitou, Pascal Ortega, Franck Lucas

Abstract:

The energy situation in tropical insular regions, as found in the French Polynesian islands, presents a number of challenges, such as high dependence on imported fuel, high transport costs from the mainland and weak electricity grids. Alternatively, these regions have a variety of renewable energy resources, which favor the exploitation of smart microgrids and energy storage technologies. With regards to the electrical energy demand, the high temperatures in these regions during the entire year implies that a large proportion of consumption is used for cooling buildings, even during the evening hours. In this context, this paper presents an air conditioning system driven by photovoltaic (PV) electricity that combines a refrigeration system and a thermochemical storage process. Thermochemical processes are able to store energy in the form of chemical potential with virtually no losses, and this energy can be used to produce cooling during the evening hours without the need to run a compressor (thus no electricity is required). Such storage processes implement thermochemical reactors in which a reversible chemical reaction between a solid compound and a gas takes place. The solid/gas pair used in this study is BaCl2 reacting with ammonia (NH3), which is also the coolant fluid in the refrigeration circuit. In the proposed system, the PV-driven electric compressor is used during the daytime either to run the refrigeration circuit when a cooling demand occurs or to decompose the ammonia-charged salt and remove the gas from thermochemical reactor when no cooling is needed. During the evening, when there is no electricity from solar source, the system changes its configuration and the reactor reabsorbs the ammonia gas from the evaporator and produces the cooling effect. In comparison to classical PV-driven air conditioning units equipped with electrochemical batteries (e.g. Pb, Li-ion), the proposed system has the advantage of having a novel storage technology with a much longer charge/discharge life cycle, and no self-discharge. It also allows a continuous operation of the electric compressor during the daytime, thus avoiding the problems associated with the on-off cycling. This work focuses on the system concept and on the efficiency study of its main components. It also compares the thermochemical with electrochemical storage as well as with other forms of thermal storage, such as latent (ice) and sensible heat (chilled water). The preliminary results show that the system seems to be a promising alternative to simultaneously fulfill cooling and energy storage needs in tropical insular regions.

Keywords: microgrid, solar air-conditioning, solid/gas sorption, thermochemical storage, tropical and insular regions

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20134 Quality Assurance Comparison of Map Check 2, Epid, and Gafchromic® EBT3 Film for IMRT Treatment Planning

Authors: Khalid Iqbal, Saima Altaf, M. Akram, Muhammad Abdur Rafaye, Saeed Ahmad Buzdar

Abstract:

Objective: Verification of patient-specific intensity modulated radiation therapy (IMRT) plans using different 2-D detectors has become increasingly popular due to their ease of use and immediate readout of the results. The purpose of this study was to test and compare various 2-D detectors for dosimetric quality assurance (QA) of intensity-modulated radiotherapy (IMRT) with the vision to find alternative QA methods. Material and Methods: Twenty IMRT patients (12 of brain and 8 of the prostate) were planned on Eclipse treatment planning system using Varian Clinac DHX on both energies 6MV and 15MV. Verification plans of all such patients were also made and delivered to Map check2, EPID (Electronic portal imaging device) and Gafchromic EBT3. Gamma index analyses were performed using different criteria to evaluate and compare the dosimetric results. Results: Statistical analysis shows the passing rate of 99.55%, 97.23% and 92.9% for 6MV and 99.53%, 98.3% and 94.85% for 15 MV energy using a criteria of ±5% of 3mm, ±3% of 3mm and ±3% of 2mm respectively for brain, whereas using ±5% of 3mm and ±3% of 3mm gamma evaluation criteria, the passing rate is 94.55% and 90.45% for 6MV and 95.25%9 and 95% for 15 MV energy for the case of prostate using EBT3 film. Map check 2 results shows the passing rates of 98.17%, 97.68% and 86.78% for 6MV energy and 94.87%,97.46% and 88.31% for 15 MV energy respectively for brain using a criteria of ±5% of 3mm, ±3% of 3mm and ±3% of 2mm, whereas using ±5% of 3mm and ±3% of 3mm gamma evaluation criteria gives the passing rate of 97.7% and 96.4% for 6MV and 98.75%9 and 98.05% for 15 MV energy for the case of prostate. EPID 6 MV and gamma analysis shows the passing rate of 99.56%, 98.63% and 98.4% for the brain, 100% and 99.9% for prostate using the same criteria as for map check 2 and EBT 3 film. Conclusion: The results demonstrate excellent passing rates were obtained for all dosimeter when compared with the planar dose distributions for 6 MV IMRT fields as well as for 15 MV. EPID results are better than EBT3 films and map check 2 because it is likely that part of this difference is real, and part is due to manhandling and different treatment set up verification which contributes dose distribution difference. Overall all three dosimeter exhibits results within limits according to AAPM report.120.

Keywords: gafchromic EBT3, radiochromic film dosimetry, IMRT verification, EPID

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20133 Adaptive Nonlinear Control of a Variable Speed Horizontal Axis Wind Turbine: Controller for Optimal Power Capture

Authors: Rana M. Mostafa, Nouby M. Ghazaly, Ahmed S. Ali

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This article introduces a solution for increasing the wind energy extracted from turbines to overcome the more electric power required. This objective provides a new science discipline; wind turbine control. This field depends on the development in power electronics to provide new control strategies for turbines. Those strategies should deal with all turbine operating modes. Here there are two control strategies developed for variable speed horizontal axis wind turbine for rated and over rated wind speed regions. These strategies will support wind energy validation, decrease manufacturing overhead cost. Here nonlinear adaptive method was used to design speed controllers to a scheme for ‘Aeolos50 kw’ wind turbine connected to permanent magnet generator via a gear box which was built on MATLAB/Simulink. These controllers apply maximum power point tracking concept to guarantee goal achievement. Procedures were carried to test both controllers efficiency. The results had been shown that the developed controllers are acceptable and this can be easily declared from simulation results.

Keywords: adaptive method, pitch controller, wind energy, nonlinear control

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20132 Approaches to Reduce the Complexity of Mathematical Models for the Operational Optimization of Large-Scale Virtual Power Plants in Public Energy Supply

Authors: Thomas Weber, Nina Strobel, Thomas Kohne, Eberhard Abele

Abstract:

In context of the energy transition in Germany, the importance of so-called virtual power plants in the energy supply continues to increase. The progressive dismantling of the large power plants and the ongoing construction of many new decentralized plants result in great potential for optimization through synergies between the individual plants. These potentials can be exploited by mathematical optimization algorithms to calculate the optimal application planning of decentralized power and heat generators and storage systems. This also includes linear or linear mixed integer optimization. In this paper, procedures for reducing the number of decision variables to be calculated are explained and validated. On the one hand, this includes combining n similar installation types into one aggregated unit. This aggregated unit is described by the same constraints and target function terms as a single plant. This reduces the number of decision variables per time step and the complexity of the problem to be solved by a factor of n. The exact operating mode of the individual plants can then be calculated in a second optimization in such a way that the output of the individual plants corresponds to the calculated output of the aggregated unit. Another way to reduce the number of decision variables in an optimization problem is to reduce the number of time steps to be calculated. This is useful if a high temporal resolution is not necessary for all time steps. For example, the volatility or the forecast quality of environmental parameters may justify a high or low temporal resolution of the optimization. Both approaches are examined for the resulting calculation time as well as for optimality. Several optimization models for virtual power plants (combined heat and power plants, heat storage, power storage, gas turbine) with different numbers of plants are used as a reference for the investigation of both processes with regard to calculation duration and optimality.

Keywords: CHP, Energy 4.0, energy storage, MILP, optimization, virtual power plant

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20131 Robust Quantum Image Encryption Algorithm Leveraging 3D-BNM Chaotic Maps and Controlled Qubit-Level Operations

Authors: Vivek Verma, Sanjeev Kumar

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This study presents a novel quantum image encryption algorithm, using a 3D chaotic map and controlled qubit-level scrambling operations. The newly proposed 3D-BNM chaotic map effectively reduces the degradation of chaotic dynamics resulting from the finite word length effect. It facilitates the generation of highly unpredictable random sequences and enhances chaotic performance. The system’s efficacy is additionally enhanced by the inclusion of a SHA-256 hash function. Initially, classical plain images are converted into their quantum equivalents using the Novel Enhanced Quantum Representation (NEQR) model. The Generalized Quantum Arnold Transformation (GQAT) is then applied to disrupt the coordinate information of the quantum image. Subsequently, to diffuse the pixel values of the scrambled image, XOR operations are performed using pseudorandom sequences generated by the 3D-BNM chaotic map. Furthermore, to enhance the randomness and reduce the correlation among the pixels in the resulting cipher image, a controlled qubit-level scrambling operation is employed. The encryption process utilizes fundamental quantum gates such as C-NOT and CCNOT. Both theoretical and numerical simulations validate the effectiveness of the proposed algorithm against various statistical and differential attacks. Moreover, the proposed encryption algorithm operates with low computational complexity.

Keywords: 3D Chaotic map, SHA-256, quantum image encryption, Qubit level scrambling, NEQR

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20130 A Near Ambient Pressure X-Ray Photoelectron Spectroscopy Study on Platinum Nanoparticles Supported on Zr-Based Metal Organic Frameworks

Authors: Reza Vakili, Xiaolei Fan, Alex Walton

Abstract:

The first near ambient pressure (NAP)-XPS study of CO oxidation over Pt nanoparticles (NPs) incorporated into Zr-based UiO (UiO for Universitetet i Oslo) MOFs was carried out. For this purpose, the MOF-based Catalysts were prepared by wetness impregnation (WI-PtNPs@UiO-67) and linker design (LD-PtNPs@UiO-67) methods along with PtNPs@ZrO₂ as the control catalyst. Firstly, the as-synthesized catalysts were reduced in situ prior to the operando XPS analysis. The existence of Pt(II) species was proved in UiO-67 by observing Pt 4f core level peaks at a high binding energy of 72.6 ± 0.1 eV. However, by heating the WI-PtNPs@UiO-67 catalyst in situ to 200 °C under vacuum, the higher BE components disappear, leaving only the metallic Pt 4f doublet, confirming the formation of Pt NPs. The complete reduction of LD-PtNPs@UiO-67 is achieved at 250 °C and 1 mbar H₂. To understand the chemical state of Pt NPs in UiO-67 during catalytic turnover, we analyzed the Pt 4f region using operando NAP-XPS in the temperature-programmed measurements (100-260 °C) with reference to PtNPs@ZrO₂ catalyst. CO conversion during NAP-XPS experiments with the stoichiometric mixture shows that LD-PtNPs@UiO-67 has a better CO turnover frequency (TOF, 0.066 s⁻¹ at 260 °C) than the other two (ca. 0.055 s⁻¹). Pt 4f peaks only show one chemical species present at all temperatures, but the core level BE shifts change as a function of reaction temperature, i.e., Pt 4f peak from 71.8 eV at T < 200 °C to 71.2 eV at T > 200 °C. As this higher BE state of 71.8 eV was not observed after in situ reductions of the catalysts and only once the CO/O₂ mixture was introduced, we attribute it to the surface saturation of Pt NPs with adsorbed CO. In general, the quantitative analysis of Pt 4f data from the operando NAP-XPS experiments shows that the surface chemistry of the Pt active phase in the two PtNPs@UiO-67 catalysts is the same, comparable to that of PtNPs@ZrO₂. The observed difference in the catalytic activity can be attributed to the particle sizes of Pt NPs, as well as the dispersion of active phase in the support, which are different in the three catalysts.

Keywords: CO oxidation, heterogeneous catalysis, MOFs, Metal Organic Frameworks, NAP-XPS, Near Ambient Pressure X-ray Photoelectron Spectroscopy

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20129 Determination of Myocardial Function Using Heart Accumulated Radiopharmaceuticals

Authors: C. C .D. Kulathilake, M. Jayatilake, T. Takahashi

Abstract:

The myocardium is composed of specialized muscle which relies mainly on fatty acid and sugar metabolism and it is widely contribute to the heart functioning. The changes of the cardiac energy-producing system during heart failure have been proved using autoradiography techniques. This study focused on evaluating sugar and fatty acid metabolism in myocardium as cardiac energy getting system using heart-accumulated radiopharmaceuticals. Two sets of autoradiographs of heart cross sections of Lewis male rats were analyzed and the time- accumulation curve obtained with use of the MATLAB image processing software to evaluate fatty acid and sugar metabolic functions.

Keywords: autoradiographs, fatty acid, radiopharmaceuticals, sugar

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20128 The Effect of Occupational Calling and Social Support on the Anxiety of Navies Who Are Sent Overseas

Authors: Yonguk L. Park, Jeonghoon Seol

Abstract:

The Republic of Korea is facing a special situation as it is the only divided country in the world. Even though Korea is facing such unstable circumstances in terms of a foreign diplomacy situation, Korea is one of the countries who, in concern for world peace, have been sending troops overseas. The troops spend more than a year at sea and may suffer from different types of psychological disorders. The purpose of this study is to try to find factors that promote psychological well-being of troops and improve their psychological health. We investigated the effect of dispatch sailors’ occupational calling and social support on anxiety before they are sent overseas and also examined the interaction between occupational calling and social support on anxiety. One hundred thirty-eight dispatched sailors participated in this study, wherein they completed the Korean calling scale, multifaceted social support scale, and anxiety scale –Y form. We analyzed the data using hierarchical regression. The results showed that after controlling gender, marital status, and the previous experiences of dispatch, those who have a higher level of occupational calling and perceived social support experienced a low level of anxiety before they are sent (β = -.276, β = -.395). Furthermore, we examined the interaction effect. If the troops’ perceived social support is high, they experience a low level of anxiety—even if they have a low level of occupational calling. This study confirms that both occupational calling and social support reduce the level of anxiety of the troops. The research provides meaningful information in understanding those who serve in the Navy’s distinctive situations and contributes to improving their psychological well-being. We suggest that sailors undergo training to have a higher occupational calling and healthy relationships with friends, families, and co-workers who provide emotional and social support.

Keywords: navy, occupational calling, social support, anxiety

Procedia PDF Downloads 255
20127 Identifying Barriers of Implementing Building Information Modelling in Construction

Authors: Kasra HosseinMostofi, Mohamadamin Oyar Hossein, Reza Mehdizadeh Anvigh

Abstract:

BIM is an innovative concept for the majority of firms operating in industry. BIM offers a new paradigm to design, construct, operate, and maintain a facility. However, even with the most conscientious use, stakeholders can run into trouble during its implementation on a project or within an organization. At times, project stakeholders are unaware of the challenges that they can face with the implementation at the project level or an organizational level. Therefore, the study aimed to identify and compile barriers associated with the BIM implementation at the project and organizational level, as per the literature. Despite the fact that innumerable advantageous involved in exploiting BIM, there are some barriers to implement it properly. These barriers have been proved as impediments for academicians and members of construction team project to take the maximum advantage of its utilization. Although some research has been conducted to identify these barriers regarding BIM implementation in construction industry, more research is needed to be carried out among academicians to identify these barriers in institutions, and most importantly, to make suggestions for eliminating these obstacles.

Keywords: building information modelling, construction, design and construction, designers

Procedia PDF Downloads 184
20126 Critical Evaluation of Groundwater Monitoring Networks for Machine Learning Applications

Authors: Pedro Martinez-Santos, Víctor Gómez-Escalonilla, Silvia Díaz-Alcaide, Esperanza Montero, Miguel Martín-Loeches

Abstract:

Groundwater monitoring networks are critical in evaluating the vulnerability of groundwater resources to depletion and contamination, both in space and time. Groundwater monitoring networks typically grow over decades, often in organic fashion, with relatively little overall planning. The groundwater monitoring networks in the Madrid area, Spain, were reviewed for the purpose of identifying gaps and opportunities for improvement. Spatial analysis reveals the presence of various monitoring networks belonging to different institutions, with several hundred observation wells in an area of approximately 4000 km2. This represents several thousand individual data entries, some going back to the early 1970s. Major issues included overlap between the networks, unknown screen depth/vertical distribution for many observation boreholes, uneven time series, uneven monitored species, and potentially suboptimal locations. Results also reveal there is sufficient information to carry out a spatial and temporal analysis of groundwater vulnerability based on machine learning applications. These can contribute to improve the overall planning of monitoring networks’ expansion into the future.

Keywords: groundwater monitoring, observation networks, machine learning, madrid

Procedia PDF Downloads 78
20125 Oscillating Water Column Wave Energy Converter with Deep Water Reactance

Authors: William C. Alexander

Abstract:

The oscillating water column (OSC) wave energy converter (WEC) with deep water reactance (DWR) consists of a large hollow sphere filled with seawater at the base, referred to as the ‘stabilizer’, a hollow cylinder at the top of the device, with a said cylinder having a bottom open to the sea and a sealed top save for an orifice which leads to an air turbine, and a long, narrow rod connecting said stabilizer with said cylinder. A small amount of ballast at the bottom of the stabilizer and a small amount of floatation in the cylinder keeps the device upright in the sea. The floatation is set such that the mean water level is nominally halfway up the cylinder. The entire device is loosely moored to the seabed to keep it from drifting away. In the presence of ocean waves, seawater will move up and down within the cylinder, producing the ‘oscillating water column’. This gives rise to air pressure within the cylinder alternating between positive and negative gauge pressure, which in turn causes air to alternately leave and enter the cylinder through said top-cover situated orifice. An air turbine situated within or immediately adjacent to said orifice converts the oscillating airflow into electric power for transport to shore or elsewhere by electric power cable. Said oscillating air pressure produces large up and down forces on the cylinder. Said large forces are opposed through the rod to the large mass of water retained within the stabilizer, which is located deep enough to be mostly free of any wave influence and which provides the deepwater reactance. The cylinder and stabilizer form a spring-mass system which has a vertical (heave) resonant frequency. The diameter of the cylinder largely determines the power rating of the device, while the size (and water mass within) of the stabilizer determines said resonant frequency. Said frequency is chosen to be on the lower end of the wave frequency spectrum to maximize the average power output of the device over a large span of time (such as a year). The upper portion of the device (the cylinder) moves laterally (surge) with the waves. This motion is accommodated with minimal loading on the said rod by having the stabilizer shaped like a sphere, allowing the entire device to rotate about the center of the stabilizer without rotating the seawater within the stabilizer. A full-scale device of this type may have the following dimensions. The cylinder may be 16 meters in diameter and 30 meters high, the stabilizer 25 meters in diameter, and the rod 55 meters long. Simulations predict that this will produce 1,400 kW in waves of 3.5-meter height and 12 second period, with a relatively flat power curve between 5 and 16 second wave periods, as will be suitable for an open-ocean location. This is nominally 10 times higher power than similar-sized WEC spar buoys as reported in the literature, and the device is projected to have only 5% of the mass per unit power of other OWC converters.

Keywords: oscillating water column, wave energy converter, spar bouy, stabilizer

Procedia PDF Downloads 107
20124 Hydrological Response of the Glacierised Catchment: Himalayan Perspective

Authors: Sonu Khanal, Mandira Shrestha

Abstract:

Snow and Glaciers are the largest dependable reserved sources of water for the river system originating from the Himalayas so an accurate estimate of the volume of water contained in the snowpack and the rate of release of water from snow and glaciers are, therefore, needed for efficient management of the water resources. This research assess the fusion of energy exchanges between the snowpack, air above and soil below according to mass and energy balance which makes it apposite than the models using simple temperature index for the snow and glacier melt computation. UEBGrid a Distributed energy based model is used to calculate the melt which is then routed by Geo-SFM. The model robustness is maintained by incorporating the albedo generated from the Landsat-7 ETM images on a seasonal basis for the year 2002-2003 and substrate map derived from TM. The Substrate file includes predominantly the 4 major thematic layers viz Snow, clean ice, Glaciers and Barren land. This approach makes use of CPC RFE-2 and MERRA gridded data sets as the source of precipitation and climatic variables. The subsequent model run for the year between 2002-2008 shows a total annual melt of 17.15 meter is generate from the Marshyangdi Basin of which 71% is contributed by the glaciers , 18% by the rain and rest being from the snow melt. The albedo file is decisive in governing the melt dynamics as 30% increase in the generated surface albedo results in the 10% decrease in the simulated discharge. The melt routed with the land cover and soil variables using Geo-SFM shows Nash-Sutcliffe Efficiency of 0.60 with observed discharge for the study period.

Keywords: Glacier, Glacier melt, Snowmelt, Energy balance

Procedia PDF Downloads 455
20123 Theoretical Investigations and Simulation of Electromagnetic Ion Cyclotron Waves in the Earth’s Magnetosphere Through Magnetospheric Multiscale Mission

Authors: A. A. Abid

Abstract:

Wave-particle interactions are considered to be the paramount in the transmission of energy in collisionless space plasmas, where electromagnetic fields confined the charged particles movement. One of the distinct features of energy transfer in collisionless plasma is wave-particle interaction which is ubiquitous in space plasmas. The three essential populations of the inner magnetosphere are cold plasmaspheric plasmas, ring-currents, and radiation belts high energy particles. The transition region amid such populations initiates wave-particle interactions among distinct plasmas and the wave mode perceived in the magnetosphere is the electromagnetic ion cyclotron (EMIC) wave. These waves can interact with numerous particle species resonantly, accompanied by plasma particle heating is still in debate. In this work we paid particular attention to how EMIC waves impact plasma species, specifically how they affect the heating of electrons and ions during storm and substorm in the Magnetosphere. Using Magnetospheric Multiscale (MMS) mission and electromagnetic hybrid simulation, this project will investigate the energy transfer mechanism (e.g., Landau interactions, bounce resonance interaction, cyclotron resonance interaction, etc.) between EMIC waves and cold-warm plasma populations. Other features such as the production of EMIC waves and the importance of cold plasma particles in EMIC wave-particle interactions will also be worth exploring. Wave particle interactions, electromagnetic hybrid simulation, electromagnetic ion cyclotron (EMIC) waves, Magnetospheric Multiscale (MMS) mission, space plasmas, inner magnetosphere

Keywords: MMS, magnetosphere, wave particle interraction, non-maxwellian distribution

Procedia PDF Downloads 62
20122 Metal-Semiconductor Transition in Ultra-Thin Titanium Oxynitride Films Deposited by ALD

Authors: Farzan Gity, Lida Ansari, Ian M. Povey, Roger E. Nagle, James C. Greer

Abstract:

Titanium nitride (TiN) films have been widely used in variety of fields, due to its unique electrical, chemical, physical and mechanical properties, including low electrical resistivity, chemical stability, and high thermal conductivity. In microelectronic devices, thin continuous TiN films are commonly used as diffusion barrier and metal gate material. However, as the film thickness decreases below a few nanometers, electrical properties of the film alter considerably. In this study, the physical and electrical characteristics of 1.5nm to 22nm thin films deposited by Plasma-Enhanced Atomic Layer Deposition (PE-ALD) using Tetrakis(dimethylamino)titanium(IV), (TDMAT) chemistry and Ar/N2 plasma on 80nm SiO2 capped in-situ by 2nm Al2O3 are investigated. ALD technique allows uniformly-thick films at monolayer level in a highly controlled manner. The chemistry incorporates low level of oxygen into the TiN films forming titanium oxynitride (TiON). Thickness of the films is characterized by Transmission Electron Microscopy (TEM) which confirms the uniformity of the films. Surface morphology of the films is investigated by Atomic Force Microscopy (AFM) indicating sub-nanometer surface roughness. Hall measurements are performed to determine the parameters such as carrier mobility, type and concentration, as well as resistivity. The >5nm-thick films exhibit metallic behavior; however, we have observed that thin film resistivity is modulated significantly by film thickness such that there are more than 5 orders of magnitude increment in the sheet resistance at room temperature when comparing 5nm and 1.5nm films. Scattering effects at interfaces and grain boundaries could play a role in thickness-dependent resistivity in addition to quantum confinement effect that could occur at ultra-thin films: based on our measurements the carrier concentration is decreased from 1.5E22 1/cm3 to 5.5E17 1/cm3, while the mobility is increased from < 0.1 cm2/V.s to ~4 cm2/V.s for the 5nm and 1.5nm films, respectively. Also, measurements at different temperatures indicate that the resistivity is relatively constant for the 5nm film, while for the 1.5nm film more than 2 orders of magnitude reduction has been observed over the range of 220K to 400K. The activation energy of the 2.5nm and 1.5nm films is 30meV and 125meV, respectively, indicating that the TiON ultra-thin films are exhibiting semiconducting behaviour attributing this effect to a metal-semiconductor transition. By the same token, the contact is no longer Ohmic for the thinnest film (i.e., 1.5nm-thick film); hence, a modified lift-off process was developed to selectively deposit thicker films allowing us to perform electrical measurements with low contact resistance on the raised contact regions. Our atomic scale simulations based on molecular dynamic-generated amorphous TiON structures with low oxygen content confirm our experimental observations indicating highly n-type thin films.

Keywords: activation energy, ALD, metal-semiconductor transition, resistivity, titanium oxynitride, ultra-thin film

Procedia PDF Downloads 294
20121 Experimental and Computational Fluid Dynamics Analysis of Horizontal Axis Wind Turbine

Authors: Saim Iftikhar Awan, Farhan Ali

Abstract:

Wind power has now become one of the most important resources of renewable energy. The machine which extracts kinetic energy from wind is wind turbine. This work is all about the electrical power analysis of horizontal axis wind turbine to check the efficiency of different configurations of wind turbines to get maximum output and comparison of experimental and Computational Fluid Dynamics (CFD) results. Different experiments have been performed to obtain that configuration with the help of which we can get the maximum electrical power output by changing the different parameters like the number of blades, blade shape, wind speed, etc. in first step experimentation is done, and then the similar configuration is designed in 3D CAD software. After a series of experiments, it has been found that the turbine with four blades at an angle of 75° gives maximum power output and increase in wind speed increases the power output. The models designed on CAD software are imported on ANSYS-FLUENT to predict mechanical power. This mechanical power is then converted into electrical power, and the results were approximately the same in both cases. In the end, a comparison has been done to compare the results of experiments and ANSYS-FLUENT.

Keywords: computational analysis, power efficiency, wind energy, wind turbine

Procedia PDF Downloads 159
20120 Failure Analysis and Verification Using an Integrated Method for Automotive Electric/Electronic Systems

Authors: Lei Chen, Jian Jiao, Tingdi Zhao

Abstract:

Failures of automotive electric/electronic systems, which are universally considered to be safety-critical and software-intensive, may cause catastrophic accidents. Analysis and verification of failures in these kinds of systems is a big challenge with increasing system complexity. Model-checking is often employed to allow formal verification by ensuring that the system model conforms to specified safety properties. The system-level effects of failures are established, and the effects on system behavior are observed through the formal verification. A hazard analysis technique, called Systems-Theoretic Process Analysis, is capable of identifying design flaws which may cause potential failure hazardous, including software and system design errors and unsafe interactions among multiple system components. This paper provides a concept on how to use model-checking integrated with Systems-Theoretic Process Analysis to perform failure analysis and verification of automotive electric/electronic systems. As a result, safety requirements are optimized, and failure propagation paths are found. Finally, an automotive electric/electronic system case study is used to verify the effectiveness and practicability of the method.

Keywords: failure analysis and verification, model checking, system-theoretic process analysis, automotive electric/electronic system

Procedia PDF Downloads 121