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CLINICAL VALUE OF SERUM TUMOR SUPPLIED GROUP OF FACTOR IN DIAGNOSIS OF EPITHELIAL OVARIAN CANCER 被引量:2
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作者 程琪辉 张喜平 曾小澜 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2003年第3期232-234,共3页
Objective: To evaluate the clinical value of serum tumor supplied group of factor (TSGF) in diagnosis of epithelial ovarian cancer. Methods: The serum TSGF was tested in 69 patients with epithelial ovarian cancer, 28... Objective: To evaluate the clinical value of serum tumor supplied group of factor (TSGF) in diagnosis of epithelial ovarian cancer. Methods: The serum TSGF was tested in 69 patients with epithelial ovarian cancer, 28 patients with benign ovarian lesion and 61 healthy women. The serum levels of vascular endothelial growth factor (VEGF) and CA125 were determined in patients with epithelial ovarian cancer and in those with benign ovarian lesion. The correlations of TSGF with VEGF and CA125 were investigated. Results: The serum level of TSGF in patients with epithelial ovarian cancer was obviously higher than in patients with benign ovarian lesion and in healthy women (P<0.01). The serum level of TSGF in patients with epithelial cancer was associated with stage and grade. TSGF was highest in stage III, followed by stage IV, and was lowest in stage I-II. The TSGF level was lower in well-differentiated tumors and was higher in poorly differentiated tumor. There were no significant difference among diagnostic value of TSGF, VEGF, and CA125 in differentiation between epithelial ovarian cancer and benign ovarian lesion (P>0.05). The serum level of TSGF and VEGF and CA125 in patients with epithelial ovarian cancer showed positive correlation (P<0.01, P<0.05, respectively). Conclusion: There is no marked difference in diagnostic value among TSGF, VEGF and CA125. TSGF has a certain value in diagnosis of epithelial ovarian cancer, and is helpful to distinguish epithelial ovarian cancer from benign ovarian lesion. 展开更多
关键词 Tumor supplied group of factor (TSGF) Ovarian cancer DIAGNOSIS
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Unit 4 of Guddu Thermal Power Plant in Pakistan operates successfully A unit supplied by China
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作者 Lu Pangen North China Electric Power Design Institute Zhang Enli 《Electricity》 1990年第2期48-50,共3页
The Guddu Thermal Power Plant of WAPDA is a main fossil powerplant in Pakistan,among which unit 4 with 210 MW in capacity suppliedby China,went into operation in 1986.Two 110 MW boiler-turbine-generator units and one ... The Guddu Thermal Power Plant of WAPDA is a main fossil powerplant in Pakistan,among which unit 4 with 210 MW in capacity suppliedby China,went into operation in 1986.Two 110 MW boiler-turbine-generator units and one 9 MW gas turbine-generator unit of phase Ⅰ projectof the power plant,provided by Skoda Export Co.of Czechoslovakia,wereput into operation in 1974,while one 210 MW boiler-turbine-generatorunit of phase Ⅱ,provided by the Technical Export Corporation of theSoviet Union,was put into operation in 1980.For the phase Ⅲ,one 210 MW boiler-turbine-generator unit,Which 展开更多
关键词 BOILER TURBINE Pakistan GENERATOR EXPORT FOSSIL supplied steam installed transformer
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Seismic performance evaluation of water supply pipes installed in a full-scale RC frame structure based on a shaking table test 被引量:1
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作者 Wu Houli Guo Endong +2 位作者 Wang Jingyi Dai Xin Dai Chenxi 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第1期163-178,共16页
As an important part of nonstructural components,the seismic response of indoor water supply pipes deserves much attention.This paper presents shaking table test research on water supply pipes installed in a full-scal... As an important part of nonstructural components,the seismic response of indoor water supply pipes deserves much attention.This paper presents shaking table test research on water supply pipes installed in a full-scale reinforced concrete(RC)frame structure.Different material pipes and different methods for penetrating the reinforced concrete floors are combined to evaluate the difference in seismic performance.Floor response spectra and pipe acceleration amplification factors based on test data are discussed and compared with code provisions.A seismic fragility study of displacement demand is conducted based on numerical simulation.The acceleration response and displacement response of different combinations are compared.The results show that the combination of different pipe materials and different passing-through methods can cause obvious differences in the seismic response of indoor riser pipes. 展开更多
关键词 water supply pipe different materials shaking table test amplification factor seismic fragility
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Traction power systems for electrified railways:evolution,state of the art,and future trends 被引量:1
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作者 Haitao Hu Yunjiang Liu +4 位作者 Yong Li Zhengyou He Shibin Gao Xiaojuan Zhu Haidong Tao 《Railway Engineering Science》 EI 2024年第1期1-19,共19页
Traction power systems(TPSs)play a vital role in the operation of electrified railways.The transformation of conventional railway TPSs to novel structures is not only a trend to promote the development of electrified ... Traction power systems(TPSs)play a vital role in the operation of electrified railways.The transformation of conventional railway TPSs to novel structures is not only a trend to promote the development of electrified railways toward high-efficiency and resilience but also an inevitable requirement to achieve carbon neutrality target.On the basis of sorting out the power supply structures of conventional AC and DC modes,this paper first reviews the characteristics of the existing TPSs,such as weak power supply flexibility and low-energy efficiency.Furthermore,the power supply structures of various TPSs for future electrified railways are described in detail,which satisfy longer distance,low-carbon,high-efficiency,high-reliability and high-quality power supply requirements.Meanwhile,the application prospects of different traction modes are discussed from both technical and economic aspects.Eventually,this paper introduces the research progress of mixed-system electrified railways and traction power supply technologies without catenary system,speculates on the future development trends and challenges of TPSs and predicts that TPSs will be based on the continuous power supply mode,employing power electronic equipment and intelligent information technology to construct a railway comprehensive energy system with renewable energy. 展开更多
关键词 Railway traction power system Future electrified railway Flexible continuous power supply Renewable energy Integrated energy system
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Analysis of faulting destruction and water supply pipeline damage from the first mainshock of the February 6,2023 Türkiye earthquake doublet 被引量:1
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作者 Xiaoqing Fan Libao Zhang +2 位作者 Juke Wang Yefei Ren Aiwen Liu 《Earthquake Science》 2024年第1期78-90,共13页
In 2023,two consecutive earthquakes exceeding a magnitude of 7 occurred in Türkiye,causing severe casualties and economic losses.The damage to critical urban infrastructure and building structures,including highw... In 2023,two consecutive earthquakes exceeding a magnitude of 7 occurred in Türkiye,causing severe casualties and economic losses.The damage to critical urban infrastructure and building structures,including highways,railroads,and water supply pipelines,was particularly severe in areas where these structures intersected the seismogenic fault.Critical infrastructure projects that traverse active faults are susceptible to the influence of fault movement,pulse velocity,and ground motions.In this study,we used a unique approach to analyze the acceleration records obtained from the seismic station array(9 strong ground motion stations)located along the East Anatolian Fault(the seismogenic fault of the MW7.8 mainshock of the 2023 Türkiye earthquake doublet).The acceleration records were filtered and integrated to obtain the velocity and displacement time histories.We used the results of an on-site investigation,jointly conducted by China Earthquake Administration and Türkiye’s AFAD,to analyze the distribution of PGA,PGV,and PGD recorded by the strong motion array of the East Anatolian Fault.We found that the maximum horizontal PGA in this earthquake was 3.0 g,and the maximum co-seismic surface displacement caused by the East Anatolian Fault rupture was 6.50 m.As the fault rupture propagated southwest,the velocity pulse caused by the directional effect of the rupture increased gradually,with the maximum PGA reaching 162.3 cm/s.We also discussed the seismic safety of critical infrastructure projects traversing active faults,using two case studies of water supply pipelines in Türkiye that were damaged by earthquakes.We used a three-dimensional finite element model of the PE(polyethylene)water pipeline at the Islahiye State Hospital and fault displacement observations obtained through on-site investigation to analyze pipeline failure mechanisms.We further investigated the effect of the fault-crossing angle on seismic safety of a pipeline,based on our analysis and the failure performance of the large-diameter Thames Water pipeline during the 1999 Kocaeli earthquake.The seismic method of buried pipelines crossing the fault was summarized. 展开更多
关键词 Türkiye earthquake fault displacement near-fault ground motion velocity pulse water supply pipeline
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Research on Alliance Decision of Dual-Channel Remanufacturing Supply Chain Considering Bidirectional Free-Riding and Cost-Sharing
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作者 Lina Dong Yeming Dai 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第9期2913-2956,共44页
This study delves into the formation dynamics of alliances within a closed-loop supply chain(CLSC)that encom-passes a manufacturer,a retailer,and an e-commerce platform.It leverages Stackelberg game for this explorati... This study delves into the formation dynamics of alliances within a closed-loop supply chain(CLSC)that encom-passes a manufacturer,a retailer,and an e-commerce platform.It leverages Stackelberg game for this exploration,contrasting the equilibrium outcomes of a non-alliance model with those of three differentiated alliance models.The non-alliance model acts as a crucial benchmark,enabling the evaluation of the motivations for various supply chain entities to engage in alliance formations.Our analysis is centered on identifying the most effective alliance strategies and establishing a coordination within these partnerships.We thoroughly investigate the consequences of diverse alliance behaviors,bidirectional free-riding and cost-sharing,and the resultant effects on the optimal decision-making among supply chain actors.The findings underscore several pivotal insights:(1)The behavior of alliances within the supply chain exerts variable impacts on the optimal pricing and demand of its members.In comparison to the non-alliance(D)model,the manufacturer-retailer(MR)and manufacturer-e-commerce platform(ME)alliances significantly lower both offline and online resale prices for new and remanufactured goods.This adjustment leads to an enhanced demand for products via the MR alliance’s offline outlets and the ME alliance’s online platforms,thereby augmenting the profits for those within the alliance.Conversely,retailer-e-commerce platform(ER)alliance tends to increase the optimal retail price and demand across both online and offline channels.Under specific conditions,alliance behavior can also increase the profits of non-alliance members,and the profits derived through alliance channels also exceed those from non-alliance channels.(2)The prevalence of bidirectional free-riding behavior largely remains constant across different alliance configurations.Across these models,bidirectional free-riding typically elevates the equilibrium prices in offline channel while negatively affecting the equilibrium prices in other channel.(3)The effect of cost-sharing shows relative uniformity across the various alliance models.Across all configurations,cost-sharing tends to reduce the manufacturer’s profits.Nonetheless,alliances initiated by the manufacturer can counteract these negative impacts,providing a strategic pathway to bolster CLSC profitability. 展开更多
关键词 Dual-channel remanufacturing supply chain ALLIANCE remanufactured products bidirectional free-riding cost-sharing
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Shaking table test study on performance and functionality of a typical telecommunication room after earthquakes
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作者 Li Bo Guo Endong +5 位作者 Sun Guoliang Ji Shuqiang Mao Chenxi Wang Tao Han Di Li Xiaofei 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第2期455-474,共20页
Large numbers of basic transceiver stations,where the telecommunication room is one of the main components,comprise an important part of the telecommunication system.After earthquakes,considerable economic loss from t... Large numbers of basic transceiver stations,where the telecommunication room is one of the main components,comprise an important part of the telecommunication system.After earthquakes,considerable economic loss from telecommunication systems is often associated with seismic damage and functional loss of the telecommunication room.However,research related to this has been limited.In this study,shaking table tests were conducted for a full-scale typical telecommunication room,including a light-steel house and the necessary communication and power supply equipment.The tests not only focused on the seismic damage to all the structures but also considered the functions of the communication and power supply of the equipment.The interactions between these facilities and their effects on communication function were also investigated.Compared with the damage to structures,the interruption of the power supply due to earthquakes is a weak link.Finally,the damage indexes,together with their threshold values of different damage states for the communication and power supply equipment,were derived from the test results.The results of this research can contribute to the literature gaps regarding seismic performance studies of telecommunication rooms,and can serve as a valuable reference for future research on its seismic fragility and economic losses evaluation. 展开更多
关键词 telecommunication light-steel house communication equipment power supply equipment seismic performance FUNCTIONALITY
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Application of Stork Optimization Algorithm for Solving Sustainable Lot Size Optimization
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作者 Tareq Hamadneh Khalid Kaabneh +6 位作者 Omar Alssayed Gulnara Bektemyssova Galymzhan Shaikemelev Dauren Umutkulov Zoubida Benmamoun Zeinab Monrazeri Mohammad Dehghani 《Computers, Materials & Continua》 SCIE EI 2024年第8期2005-2030,共26页
The efficiency of businesses is often hindered by the challenges encountered in traditional Supply Chain Manage-ment(SCM),which is characterized by elevated risks due to inadequate accountability and transparency.To a... The efficiency of businesses is often hindered by the challenges encountered in traditional Supply Chain Manage-ment(SCM),which is characterized by elevated risks due to inadequate accountability and transparency.To address these challenges and improve operations in green manufacturing,optimization algorithms play a crucial role in supporting decision-making processes.In this study,we propose a solution to the green lot size optimization issue by leveraging bio-inspired algorithms,notably the Stork Optimization Algorithm(SOA).The SOA draws inspiration from the hunting and winter migration strategies employed by storks in nature.The theoretical framework of SOA is elaborated and mathematically modeled through two distinct phases:exploration,based on migration simulation,and exploitation,based on hunting strategy simulation.To tackle the green lot size optimization issue,our methodology involved gathering real-world data,which was then transformed into a simplified function with multiple constraints aimed at optimizing total costs and minimizing CO_(2) emissions.This function served as input for the SOA model.Subsequently,the SOA model was applied to identify the optimal lot size that strikes a balance between cost-effectiveness and sustainability.Through extensive experimentation,we compared the performance of SOA with twelve established metaheuristic algorithms,consistently demonstrating that SOA outperformed the others.This study’s contribution lies in providing an effective solution to the sustainable lot-size optimization dilemma,thereby reducing environmental impact and enhancing supply chain efficiency.The simulation findings underscore that SOA consistently achieves superior outcomes compared to existing optimization methodologies,making it a promising approach for green manufacturing and sustainable supply chain management. 展开更多
关键词 OPTIMIZATION supply chain management sustainable lot size optimization BIO-INSPIRED METAHEURISTIC STORK
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Influences of the Fresh Air Volume on the Removal of Cough-Released Droplets in a Passenger Car of a High-Speed Train Using CFD
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作者 Jun Xu Kai Bi +7 位作者 Yibin Lu TiantianWang Hang Zhang Zeyuan Zheng Fushan Shi Yaxin Zheng Xiaoying Li Jingping Yang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2727-2748,共22页
The spread and removal of pollution sources,namely,cough-released droplets in three different areas(front,middle,and rear areas)of a fully-loaded passenger car in a high-speed train under different fresh air flow volu... The spread and removal of pollution sources,namely,cough-released droplets in three different areas(front,middle,and rear areas)of a fully-loaded passenger car in a high-speed train under different fresh air flow volume were studied using computational fluid dynamics(CFD)method.In addition,the structure of indoor flow fields was also analysed.The results show that the large eddies are more stable and flow faster in the air supply under Mode 2(fresh air volume:2200m3/h)compared to Mode 1(fresh air volume:1100m3/h).By analysing the spreading process of droplets sprayed at different locations in the passenger car and with different particle sizes,the removal trends for droplets are found to be similar under the two air supply modes.However,when increasing the fresh air flow volume,the droplets in the middle and front areas of the passenger car are removed faster.When the droplets had dispersed for 60s,Mode 2 exhibited a removal rate approximately 1%–3%higher than Mode 1 for small and medium-sized droplets with diameters of 10 and 50μm.While those in the rear area,the situation is reversed,with Mode 1 slightly surpassing Mode 2 by 1%–3%.For large droplets with a diameter of 100μm,both modes achieved a removal rate of over 96%in all three regions at the 60 s.The results can provide guidance for air supply modes of passenger cars of high-speed trains,thus suppressing the spread of virus-carrying droplets and reducing the risk of viral infection among passengers. 展开更多
关键词 Cough-released pollutants CFD ventilation inside trains supply air volume
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A Proposed Feature Selection Particle Swarm Optimization Adaptation for Intelligent Logistics--A Supply Chain Backlog Elimination Framework
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作者 Yasser Hachaichi Ayman E.Khedr Amira M.Idrees 《Computers, Materials & Continua》 SCIE EI 2024年第6期4081-4105,共25页
The diversity of data sources resulted in seeking effective manipulation and dissemination.The challenge that arises from the increasing dimensionality has a negative effect on the computation performance,efficiency,a... The diversity of data sources resulted in seeking effective manipulation and dissemination.The challenge that arises from the increasing dimensionality has a negative effect on the computation performance,efficiency,and stability of computing.One of the most successful optimization algorithms is Particle Swarm Optimization(PSO)which has proved its effectiveness in exploring the highest influencing features in the search space based on its fast convergence and the ability to utilize a small set of parameters in the search task.This research proposes an effective enhancement of PSO that tackles the challenge of randomness search which directly enhances PSO performance.On the other hand,this research proposes a generic intelligent framework for early prediction of orders delay and eliminate orders backlogs which could be considered as an efficient potential solution for raising the supply chain performance.The proposed adapted algorithm has been applied to a supply chain dataset which minimized the features set from twenty-one features to ten significant features.To confirm the proposed algorithm results,the updated data has been examined by eight of the well-known classification algorithms which reached a minimum accuracy percentage equal to 94.3%for random forest and a maximum of 99.0 for Naïve Bayes.Moreover,the proposed algorithm adaptation has been compared with other proposed adaptations of PSO from the literature over different datasets.The proposed PSO adaptation reached a higher accuracy compared with the literature ranging from 97.8 to 99.36 which also proved the advancement of the current research. 展开更多
关键词 Optimization particle swarm optimization algorithm feature selection LOGISTICS supply chain management backlogs
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Assessing the Impact of Catastrophic Electricity Loss on the Food Supply Chain
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作者 Simon Blouin Alexander Herwix +2 位作者 Morgan Rivers Ross J.Tieman David C.Denkenberger 《International Journal of Disaster Risk Science》 SCIE CSCD 2024年第4期481-493,共13页
The food supply chain’s heavy reliance on electricity poses signifcant vulnerabilities in the event of prolonged and widespread power disruptions.This study introduces a system-dynamics model that integrates fve crit... The food supply chain’s heavy reliance on electricity poses signifcant vulnerabilities in the event of prolonged and widespread power disruptions.This study introduces a system-dynamics model that integrates fve critical infrastructures-electric grid,liquid fossil fuels,Internet,transportation,and human workforce-to evaluate the resilience of food supply chains to major power outages.We validated the model using the 2019 Venezuelan blackouts as a case study,demonstrating its predictive validity.We then explored how more extreme electricity losses would disrupt the supply chain.More specifcally,we modeled the impact of a large-scale cyberattack on the US electric grid and a high-altitude electromagnetic pulse(HEMP)event.A cyberattack severely damaging the US electric grid and allowing for recovery within a few weeks or months would lead to substantial drops in food consumption.However,it would likely still be possible to provide adequate calories to everyone,assuming that food is equitably distributed.In contrast,a year-long recovery from a HEMP event afecting most of the continental United States could precipitate a state of famine.Our analysis represents a frst attempt at quantifying how food availability progressively worsens as power outages extend over time.Our open-source model is made publicly available,and we encourage its application to other catastrophic scenarios beyond those specifcally considered in this work(for example,extreme solar storms,high-lethality pandemics). 展开更多
关键词 Cyberattack ELECTRICITY Food supply chains Global catastrophic risk High-altitude electromagnetic pulse System dynamics
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Evaluation of the Impact of Refined Quality Control Management Model on the Qualified Rate of Disinfection and Sterilization of Surgical Instruments in the Sterilization Supply Center 被引量:1
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作者 Qin Liu 《Journal of Clinical and Nursing Research》 2024年第1期168-173,共6页
Objective:To evaluate the application value of a refined quality control management model for a sterilization supply center.Methods:A retrospective analysis was conducted on the work situation of the sterilization sup... Objective:To evaluate the application value of a refined quality control management model for a sterilization supply center.Methods:A retrospective analysis was conducted on the work situation of the sterilization supply center from January 2021 to January 2023.The work situation before January 31,2022,was classified as the control group;a routine quality control management model was implemented,and the work situation after January 31,2022,was classified as the observation group.The quality of medical device management and department satisfaction between the two groups were compared.Results:The timely recovery and supply rate,classification and cleaning pass rate,disinfection pass rate,packaging pass rate,sterilization pass rate,and department satisfaction score in the observation group were all higher than those of the control group(P<0.05).Conclusion:Implementing a refined quality control management model in the sterilization supply center can improve the quality management level of medical devices and department satisfaction and is worthy of promotion. 展开更多
关键词 Refined quality control management model Sterilization supply center Disinfection and sterilization pass rate
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赛德西港用于船舶减排的陆上可再生能源供电评估
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作者 Merna Makram Ameen M.Bassam +1 位作者 Adel A.Tawfik Waleed Yehia 《哈尔滨工程大学学报(英文版)》 CSCD 2024年第2期506-524,共19页
Air pollution from shipping is becoming a critical issue,particularly in dense hub port cities.One proposed solution to minimize ship-based emissions at ports is the implementation of an Onshore Power Supply(OPS)syste... Air pollution from shipping is becoming a critical issue,particularly in dense hub port cities.One proposed solution to minimize ship-based emissions at ports is the implementation of an Onshore Power Supply(OPS)system.OPS allows ships to shut off their auxiliary engines and instead connect to the port grid.While there have been numerous studies conducted on ports in Europe and the United States,little research has been done on Egyptian ports.Therefore,this paper aims to investigate the feasibility of implementing OPS at Port Said West Port in Egypt,aligning with Egypt Vision 2030’s goals for addressing climate change.The research primarily focuses on analyzing data collected from calling ships to generate socio-economic and cost-effectiveness analyses of OPS.To further enhance the environmental benefits of OPS,the paper proposes the use of solar energy as the OPS electricity source.The findings of the study revealed that by relying on the national grid,emissions can be reduced by 28%.Moreover,it is predicted that this reduction could reach 100%if electricity generation is solely based on solar energy.Additionally,the economic analysis demonstrates promising profitability,with a payback period of approximately two years. 展开更多
关键词 Onshore power supply Port sustainability Shipping emissions inventory Solar energy Photovoltaic systems
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Low-frequency oscillation of train-network system considering traction power supply mode
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作者 Yuchen Liu Xiaoqin Lyu +1 位作者 Mingyuan Chang Qiqi Yang 《Railway Engineering Science》 EI 2024年第2期244-256,共13页
The low-frequency oscillation(LFO)has occurred in the train-network system due to the introduction of the power electronics of the trains.The modeling and analyzing method in current researches based on electrified ra... The low-frequency oscillation(LFO)has occurred in the train-network system due to the introduction of the power electronics of the trains.The modeling and analyzing method in current researches based on electrified railway unilateral power supply system are not suitable for the LFO analysis in a bilateral power supply system,where the trains are supplied by two traction substations.In this work,based on the single-input and single-output impedance model of China CRH5 trains,the node admittance matrices of the train-network system both in unilateral and bilateral power supply modes are established,including three-phase power grid,traction transformers and traction network.Then the modal analysis is used to study the oscillation modes and propagation characteristics of the unilateral and bilateral power supply systems.Moreover,the influence of the equivalent inductance of the power grid,the length of the transmission line,and the length of the traction network are analyzed on the critical oscillation mode of the bilateral power supply system.Finally,the theoretical analysis results are verified by the time-domain simulation model in MATLAB/Simulink. 展开更多
关键词 Low-frequency oscillation Train-network system Modal analysis Bilateral power supply Participation factor
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Study on green power supply modes for heavy load in Remote Areas
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作者 Yu Li Yixi Cuomu +4 位作者 Yiming Gao Guoqin Lv Weiwei Lin Sirui Li Changchun Zhou 《Global Energy Interconnection》 EI CSCD 2024年第4期475-485,共11页
In this study,the present situation and characteristics of power supply in remote areas are summarized.By studying the cases of power supply projects in remote areas,the experience is analyzed and described,and the ap... In this study,the present situation and characteristics of power supply in remote areas are summarized.By studying the cases of power supply projects in remote areas,the experience is analyzed and described,and the applicability of related technologies,such as grid-forming storage and power load management,is studied,including grid-connection technologies,such as grid-forming converters and power load management.On this basis,three power-supply modes were proposed.The application scenarios and advantages of the three modes were compared and analyzed.Based on the local development situation,the temporal sequences of the three schemes are described,and a case study was conducted.The study of the heavy-load power supply mode in remote areas contributes to solving the problem of heavy-load green power consumption in remote areas and promoting the further development of renewable energy. 展开更多
关键词 Remote area Renewable energy Grid-forming storage Power load management Power supply mode
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Legume green manure can intensify the function of chemical nitrogen fertilizer substitution via increasing nitrogen supply and uptake of wheat
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作者 Jingui Wei Zhilong Fan +5 位作者 Falong Hu Shoufa Mao Fang Yin Qiming Wang Qiang Chai Wen Yin 《The Crop Journal》 SCIE CSCD 2024年第4期1222-1232,共11页
Achieving the green development of agriculture requires the reduction of chemical nitrogen(N)fertilizer input.Previous studies have confirmed that returning green manure to the field is an effective measure to improve... Achieving the green development of agriculture requires the reduction of chemical nitrogen(N)fertilizer input.Previous studies have confirmed that returning green manure to the field is an effective measure to improve crop yields while substituting partial chemical N fertilizer.However,it remains unclear how to further intensify the substituting function of green manure and elucidate its underlying agronomic mechanism.In a split-plot field experiment in spring wheat,different green manures returned to the field under reduced chemical N supply was established in an oasis area since 2018,in order to investigate the effect of green manure and reduced N on grain yield,N uptake,N use efficiency(NUE),N nutrition index,soil organic matter,and soil N of wheat in 2020-2022.Our results showed that mixed sown common vetch and hairy vetch can substitute 40%of chemical N fertilizer without reducing grain yield or N accumulation.Noteworthily,mixed sown common vetch and hairy vetch under reduced N by 20%showed the highest N agronomy efficiency and recovery efficiency,which were 92.0%and 46.0%higher than fallow after wheat harvest and conventional N application rate,respectively.The increase in NUE of wheat was mainly attributed to mixed sown common vetch and hairy vetch,which increased N transportation quantity and transportation rate at pre-anthesis,enhanced N harvest index,optimized N nutrition index,and increased activities of nitrate reductase and glutamine synthetase of leaf,respectively.Meanwhile,mixed sown common vetch and hairy vetch under reduced N by 20%improved soil organic matter and N contents.Therefore,mixed sown common vetch and hairy vetch can substitute 40%of chemical N fertilizer while maintaining grain yield and N accumulation,and it combined with reduced chemical N by 20%or 40%improved NUE of wheat via enhancing N supply and uptake. 展开更多
关键词 Legume green manure Reduced N input WHEAT N uptake and supply Agronomic mechanism
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Consideration of the influence of supports in modeling the electromagnetic fields of 25 kV traction networks under emergency conditions
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作者 Konstantin Suslov Andrey Kryukov +1 位作者 Ekaterina Voronina Pavel Ilyushin 《Global Energy Interconnection》 EI CSCD 2024年第4期528-540,共13页
Single-phase 25 kV traction networks of electrified alternating current(AC)railways create electromagnetic fields(EMFs)with significant levels of intensity.The most intense magnetic fields occur when short circuits ex... Single-phase 25 kV traction networks of electrified alternating current(AC)railways create electromagnetic fields(EMFs)with significant levels of intensity.The most intense magnetic fields occur when short circuits exist between the contact wire and rails or ground.Despite the short duration of exposure,they can adversely affect electronic devices and induce significant voltages in adjacent power lines,which is dangerous for operating personnel.Although numerous investigations have focused on modeling the EMF of traction networks and power lines,the challenge of determining the three-dimensional electromagnetic fields near metal supports during the flow of a short-circuit current through them is yet to be resolved.In this case,the field has a complex spatial structure that significantly complicates the calculations of intensities.This study proposes a methodology,algorithms,software,and digital models for determining the EMF in the described emergency scenarios.During the modeling process,the objects being studied were represented by segments of thin wires to analyze the distribution of the electric charge and calculate the intensities of the electric and magnetic fields.This approach was implemented in the Fazonord software,and the modeling results show a substantial increase in EMF levels close to the support,with a noticeable decrease in the levels as the distance from it increases.The procedure implemented in the commercial software Fazonord is universal and can be used to determine electromagnetic fields at any electrical power facility that includes live parts of limited length.Based on the proposed procedure,the EMF near the supports of overhead power lines and traction networks of various designs could be determined,the EMF levels at substations can be calculated,and the influence of metal structures located near traction networks,such as pedestrian crossings at railway stations,can be considered. 展开更多
关键词 Power supply systems AC railways Emergency conditions Electromagnetic fields near supports MODELING Electromagnetic safety
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Wireless Power Supply Based on MNG-MNZ Metamaterial for Cardiac Pacemakers
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作者 Weihua Chen Jingtao Jia +2 位作者 Xiaoheng Yan Yuhang Song Jiayi Li 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第1期103-112,共10页
To solve the low power transfer efficiency and magnetic field leakage problems of cardiac pacemaker wireless powering, we proposed a wireless power supply system suitable for implanted cardiac pacemaker based on mu-ne... To solve the low power transfer efficiency and magnetic field leakage problems of cardiac pacemaker wireless powering, we proposed a wireless power supply system suitable for implanted cardiac pacemaker based on mu-negative(MNG) and mu-nearzero(MNZ) metamaterials. First, a hybrid metamaterial consisted of central MNG unit for magnetic field concentration and surrounding MNZ units for magnetic leakage shielding was established by theoretical calculation. Afterwards, the magnetic field distribution of wireless power supply system with MNG-MNZ metamaterial slab was acquired via finite element simulation and verified to be better than the distribution with conventional MNG slab deployed. Finally, an experimental platform of wireless power supply system was established with which power transfer experiment and system temperature rise experiment were conducted.Simulation and experimental results showed that the power transfer efficiency was improved from 44.44%,19.42%, 8.63% and 6.19% to 55.77%, 62.39%, 20.81%and 14.52% at 9.6 mm, 20 mm, 30 mm and 50 mm,respectively. The maximum SAR acquired by SAR simulation under human body environment was-7.14 dbm and maximum reduction of the magnetic field strength around the receiving coil was 2.82 A/m. The maximum temperature rise during 30min charging test was 3.85℃,and the safety requirements of human bodies were met. 展开更多
关键词 Cardiac pacemaker MNG metamaterial MNZ metamaterial Wireless power supply system
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Integrated design and performance optimization of three-electrode sliding discharge plasma power supply
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作者 Borui ZHENG Linwu WANG +4 位作者 Jianbo ZHANG Shaojie QI Yuhong CHEN Haodong LIU Dongliang BIAN 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第11期152-161,共10页
The three-electrode sliding dielectric barrier discharge(TES-DBD) plasma actuator significantly enhances the ionization rate and momentum exchange between charged particles and neutral particles by incorporating a par... The three-electrode sliding dielectric barrier discharge(TES-DBD) plasma actuator significantly enhances the ionization rate and momentum exchange between charged particles and neutral particles by incorporating a parallel DC electrode into the standard DBD design. This design improves the body force and induced jet velocity while allowing flexible control of the induced jet angle, overcoming the limitations of discharge extension and uncontrollable direction in traditional DBD plasma actuators. An integrated plasma power supply has been designed specifically for TES-DBD plasma actuators, streamlining the power supply management. The methodology involves designing the circuit topology for the TES-DBD power supply, followed by simulating and validating its operating principles using Multisim software. The operational performance of the power supply is evaluated through a comprehensive analysis of its electrical,thermal, and aerodynamic properties specific to TES-DBD plasma actuation. 展开更多
关键词 plasma flow control dielectric barrier discharge three-electrode sliding discharge plasma power supply
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Research on the longitudinal protection of a through-type cophase traction direct power supply system based on the empirical wavelet transform
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作者 Lu Li Zeduan Zhang +5 位作者 Wang Cai Qikang Zhuang Guihong Bi Jian Deng Shilong Chen Xiaorui Kan 《Global Energy Interconnection》 EI CSCD 2024年第2期206-216,共11页
This paper proposes a longitudinal protection scheme utilizing empirical wavelet transform(EWT)for a through-type cophase traction direct power supply system,where both sides of a traction network line exhibit a disti... This paper proposes a longitudinal protection scheme utilizing empirical wavelet transform(EWT)for a through-type cophase traction direct power supply system,where both sides of a traction network line exhibit a distinctive boundary structure.This approach capitalizes on the boundary’s capacity to attenuate the high-frequency component of fault signals,resulting in a variation in the high-frequency transient energy ratio when faults occur inside or outside the line.During internal line faults,the high-frequency transient energy at the checkpoints located at both ends surpasses that of its neighboring lines.Conversely,for faults external to the line,the energy is lower compared to adjacent lines.EWT is employed to decompose the collected fault current signals,allowing access to the high-frequency transient energy.The longitudinal protection for the traction network line is established based on disparities between both ends of the traction network line and the high-frequency transient energy on either side of the boundary.Moreover,simulation verification through experimental results demonstrates the effectiveness of the proposed protection scheme across various initial fault angles,distances to faults,and fault transition resistances. 展开更多
关键词 Through-type Cophase traction direct power supply system Traction network Empirical wavelet transform(EWT) Longitudinal protection
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