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[IEEE 2018 IEEE International Students' Conference on Electrical, Electronics and Computer Science (SCEECS) - Bhopal, India (2018.2.24-2018.2.25)] 2018 IEEE International Students' Conference on Electrical, Electronics and Computer Science (SCEECS) - A Five –level PWM Inverter for Hybrid PV/Fuel Cell/Battery Standalone power System
摘要： Renewable energy sources (RES) based generation has emerged as one of the best option due to global environmental concerns, especially for off-grid load locations like islands, mountains, etc., where diesel generators are main source of power generation. This paper presents a case study of an efficient photovoltaic (PV) generation integrated with multilevel inverter to ensure regulated power at user end. Perturb and observe (PO) algorithm based maximum power point tracking (MPPT) has been used to track maximum power for PV applications. However in PV based power generation, control problem arises due to large variation of irradiance round the clock. This problem can be overcome by hybrid PV generation system, i.e., application of secondary power source as battery and fuel cell integrated with PV generation unit. The DC output of standalone hybrid PV-SOFC-Battery generation system is inverted by a single-phase multilevel converter. This output of developed standalone hybrid PV-SOFC-Battery generation system is used to supply the single-phase load. This inverter offers less THD which is compared with three level inverter.
关键词： Battery,Hybrid Power System,Photovoltaic system,Fuel cell,MPPT
更新于2025-09-23 15:23:52
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Optimization of X-ray image acquisition and reconstruction for a C-arm CBCT system with a flat-panel detector
摘要： A modern cone-beam computed tomography (CBCT) system with a C-arm gantry incorporating a large-area flat-panel detector is an important imaging tool widely used for diagnosis and image-guidance in spine surgery, orthopedic and interventional suite, and image-guided radiation therapy. In this study, the experimental prototype CBCT imaging platform consists of a benchtop system that is integrated with a cone-beam X-ray tube, a collimator, an anti-scatter grid, and a large-area TFT-based flat-panel detector. The different projection images in the C-arm CT system were usually acquired at short scanning angles with a constant interval for various exposure conditions. The performance of CT imaging quality was performed using the Feldkamp, Davis and Kress (FDK) reconstruction algorithm through acquired two-dimensional projection images at different scanning angles and projection numbers. Quantitative analysis of the image quality was performed by using the cone-beam CT phantom for spatial resolution, low-contrast resolution, noise, and two different phantoms, such as the head and pelvis.
关键词： Flat-panel X-ray detector,3D image reconstruction,Cone-beam CT system,C-arm CT system
更新于2025-09-23 15:23:52
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Integrated sizing of hybrid PV-wind-battery system for remote island considering the saturation of each renewable energy resource
摘要： The proliferation of renewable energy particularly the combination of solar-wind power and storage bank, is likely to be occupied throughout the world, to mitigate the local energy concerns, improve the energy supply opportunities for off-grid communities and vitiate environmental pollution concerns as well as ease the intensity of energy consumption. To mitigate the disharmony between renewable energy (RE) generation and supply, a cost-optimal autonomous hybrid renewable energy system is developed and comparatively analyzed, considering the saturation level of each involved RE source based on various technical and economic key indicators. This study proposes a mathematical model to comprehensively analyze the effect of varying saturation, i.e. increasing the saturation of one resource meanwhile decreasing the ratio of other resource, on battery bank size, state of charge (SOC), loss of power supply, excess energy, net present cost, levelized cost of energy (COE) and payback time. A saturation factor is introduced, from 0 to 1 value with step size 0.02, where zero represents the wind-only system and one represents the solar-only system. Three different systems are considered, with different wind turbine sizes (total 150 configurations), to comparatively analyze the different energy systems and the result reveals that smaller wind turbine size (2 kW) with 90% saturation of wind energy is the most cost-effective system for the proposed remote island. In addition, the solar-alone and wind-alone systems are compared, showing that the wind-only system can provide good performance as compare to solar-only. Furthermore, the effects of the saturation factor on COE, battery bank size, SOC, excess energy, system reliability and different load demands are analyzed. Energy balance analysis of whole year and simulation performance of the system is accomplished to verify the system reliability. Sensitivity analysis reveals that wind energy, battery cost and load has a significant impact on COE than other factors.
关键词： Hybrid Renewable system reliability,Cost of energy,Net present cost,Renewable energy saturation,Energy balance,Solar-wind-battery system
更新于2025-09-23 15:23:52
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[IEEE 2018 7th International Conference on Renewable Energy Research and Applications (ICRERA) - Paris, France (2018.10.14-2018.10.17)] 2018 7th International Conference on Renewable Energy Research and Applications (ICRERA) - Performance-Improved Maximum Power Point Tracking Control for PV System
摘要： Dc distribution systems are gaining attracted because of expanding the utilization of solar photovoltaic (PV) power. In such a situation, the design of the maximum power point tracking (MPPT) controllers should consider not only varying solar irradiance but also the dc bus voltage fluctuation. The purpose of this paper is to present a performance-improved MPPT controller using a derivative control to a PV panel voltage. The proposed method provides better performances than an existing reported method which uses the derivative control to a reactor current of a dc-dc converter. It is verified that the proposed method obtains quick responses to the rapid change of solar irradiance and dc bus voltage compared to conventional methods.
关键词： dc distribution system,dynamic response,PV system,maximum power point tracking (MPPT),dc-dc converter
更新于2025-09-23 15:23:52
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[IEEE 2018 2nd International Symposium on Multidisciplinary Studies and Innovative Technologies (ISMSIT) - Ankara, Turkey (2018.10.19-2018.10.21)] 2018 2nd International Symposium on Multidisciplinary Studies and Innovative Technologies (ISMSIT) - The setup cost payback times of 1 kW fixed and dual axis tracking solar energy systems
摘要： In this paper an 80 W optimally tilted fixed solar energy system and an 80 W azimuth-altitude dual solar axis tracking system are designed and analyzed. The systems are mounted on the roof an industrial building in Sakarya, Turkey. The fixed solar energy system is tilted at the yearly optimum tilt angle for the city. The tracking system is designed to follow the Sun’s position by means of solar mathematics. The electrical behavior of the systems are observed for six months and the obtained results are used to evaluate the setup cost payback times of 1 kW applications. In conclusion it is determined that the fixed solar energy system pay back its setup cost in 7.18 years and the tracking solar energy system in 10.73 years.
关键词： solar tracking system,fixed solar energy system,optimally tilted,setup cost payback time
更新于2025-09-23 15:23:52
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Design and analysis of a multigeneration system with concentrating photovoltaic thermal (CPV/T) and hydrogen storage
摘要： Concentrated photovoltaics (CPV) is an auspicious technology to overcome the high cost problem of highly efficient multi-junction solar cells. However, due to huge concentration of light energy, high heat flux dissipation from a confined space is a challenge. The proposed system here is first of its type to apply and thermodynamically analyze the Nucleate Pool Boiling Heat Transfer (NBHT) for thermal management of CPV. In order to increase overall efficiency of CPV system, a multigeneration system using concentrated photovoltaic thermal (CPV/T) and hydrogen storage is designed and thermodynamically analyzed to fulfill electricity, hot and cold water, heating ventilation and cooling (HVAC) requirement of a residential community with continuous operation. A part of the generated electricity from CPV is used to power the electrolyzer to produce hydrogen and oxygen. The produced gases are stored, and reused by proton exchange membrane fuel cell (PEMFC) to fulfill the system's electrical energy requirement during night time and unfavourable energy conditions in day time. The resultant thermal energy from CPV/T is used for the heating, hot water and cooling requirement of the buildings by employing lithium bromide absorption chiller (AbC). A humidity harvesting system is connected, at the outlet of the absorption chiller, to convert humid air into water and ventilation air requirement of the building. The designed system performs at 67.52% overall energy efficiency, 34.89% of overall exergy efficiency and up to 1862 times concentration ratio at designed steady-state conditions. The results show that with an increase in boiling temperature of NBHT from 353 K to 373 K, the maximum concentration ratio ability increases significantly from 1392 to 2400 times due to increase in critical heat flux, while the electrical efficiency of the CPV system decreases from 28.65% to 27.09% because of increase in cell temperature. To verify the performance of the designed system for different locations, operating conditions and capacities, the effects of Direct Normal Irradiance (IDNI), ambient temperature, relative humidity ratio and the installed capacity are also analyzed by the parametric studies.
关键词： Concentrated photovoltaics,Multigeneration system,Hydrogen storage,Exergy,Solar photovoltaics/thermal system,Electrolyzer and fuel cell
更新于2025-09-23 15:23:52
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[IEEE 2018 IEEE 7th Data Driven Control and Learning Systems Conference (DDCLS) - Enshi (2018.5.25-2018.5.27)] 2018 IEEE 7th Data Driven Control and Learning Systems Conference (DDCLS) - Quantum Noise Protection via Weak Measurement for Quantum Mixed States
摘要： Due to the interaction with the environment, a quantum state is often affected by the different types of noises which becomes to one of the biggest problems for practical quantum computation. We study the possibility of protecting the mixed state of a quantum system that goes through noise by weak measurements and control operations. The aim is to find the optimal measurement strength and control operations and make the input and output states as close as possible. We show that our scheme can effectively protect arbitrary mixed states against typical types of noise sources: amplitude damping, phase damping and amplitude-phase damping. The optimal measurement and control operators are deduced in different bases of the Bloch sphere to find the best control scheme for each type of noise. The effectiveness of our control scheme is demonstrated by simulation results.
关键词： quantum system control,Open quantum system,optimal noise protection,weak measurement
更新于2025-09-23 15:23:52
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A heterobimetallic Au(III)?Pt(II) photocatalyst for water reduction to hydrogen
摘要： A supramolecular complex, [Au(C^N^C)(C≡CC6H4C≡C)Pt(terpy)]+, has been synthesized as a photocatalyst for water reduction. This compound consists of a cyclometalated alkyngold(III) photosensitizer and a platinum(II) terpyridine complex bridged through a central phenylethynyl group.
关键词： heterobimetallic system,hydrogen evolution,photocatalyst
更新于2025-09-23 15:23:52
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Soliton slow light for closed loop quantum systems
摘要： This paper describes the dynamics of solitonic pulse propagation in a closed loop quantum system comprised of five atomic energy levels. Although the propagation of an intense probe pulse suffers losses and broadening in linear regime, there exist specific conditions where the probe pulse is found to become robust during its propagation. We attribute this regime to the formation of an optical soliton with a slow group velocity because of the balance between the dispersion and Kerr optical nonlinearity. Results obtained are based on the theoretical model using the coupled Maxwell-Bloch equations for the nonlinear propagation.
关键词： Optical solitons,Kerr nonlinearity,Nonlinear pulse propagation,Closed-loop quantum system
更新于2025-09-23 15:23:52
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Noise-Free Rule-Based Fuzzy Image Enhancement
摘要： Different kinds of noises have considerable effects on most of image sensing systems. Suitable image contrast enhancement algorithms can improve contrast or retain detail information while reducing noises as well. Fuzzy representation of an image provides a reliable analysis when inexactness occurred at the gray level values. This paper presents a fuzzy-based novel image contrast enhancement method. Several image quality indices, such as similarity, naturalness, and mean brightness preserving examined and experimentally show the effectiveness of the proposed technique in comparison with well-known image enhancement methods such as histogram equalization and contrast limited adaptive histogram equalization methods.
关键词： Image Robustness and Naturalness,Image Quality Index,Image Enhancement,Fuzzy System
更新于2025-09-23 15:23:52