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Fuzzy multi-criteria decision-making method-based operational assessment of Chinese electricity markets
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作者 Weijie Wu Dongwei Li +2 位作者 Hui Sun Yixin Li Yining Zhang 《Global Energy Interconnection》 EI CSCD 2024年第6期733-748,共16页
The evaluation of the electricity market is crucial for fostering market construction and development.An accurate assessment of the electricity market reveals developmental trends,identifies operational issues,and con... The evaluation of the electricity market is crucial for fostering market construction and development.An accurate assessment of the electricity market reveals developmental trends,identifies operational issues,and contributes to stable and healthy market growth.This study investigated the characteristics of electricity markets in different provinces and synthesized a comprehensive set of evaluation indicators to assess market effectiveness.The evaluation framework,comprising nine indicators organized into two tiers,was constructed based on three aspects:market design,market efficiency,and developmental coordination.Furthermore,a novel fuzzy multi-criteria decision-making evaluation model for electricity market performance was developed based on the Fuzzy-BWM and fuzzy COPRAS methodologies.This model aimed to ensure both accuracy and comprehensiveness in market operation assessment.Subsequently,empirical analyses were conducted on four typical provincial-level electricity markets in China.The results indicate that Guangdong’s electricity market performed best because of its effective balance of stakeholder interests and adherence to contractual integrity principles.Zhejiang and Shandong ranked second and third,respectively,whereas Sichuan exhibited the poorest market performance.Sichuan’s electricity market must be improved in terms of market design,such that market players can obtain a fairly competitive environment.The sensitivity analysis of the constructed indicators verified the effectiveness of the evaluation model proposed in this study.Finally,policy recommendations were proposed to facilitate the sustainable development of China’s electricity markets with the objective of transforming them into efficient and secure markets adaptable to the evolution of novel power systems. 展开更多
关键词 Electricity market operational assessment Fuzzy best-worst method Fuzzy complex proportional assessment Fuzzy multi-criteria decision making
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Observation of the Effect of Video Assessment Method on the Operation Skills of Individual Nurses
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作者 Jianhua Qin Xiaolu Wan Nannan Ma 《Journal of Clinical and Nursing Research》 2024年第8期122-128,共7页
Objective:To explore the application effect of video assessment method in clinical nurses’nursing operation skills.Method:To select 58 nurses who participated in the individual soldier standard in the children’s hos... Objective:To explore the application effect of video assessment method in clinical nurses’nursing operation skills.Method:To select 58 nurses who participated in the individual soldier standard in the children’s hospital in 2019 and 2020 as the research objects,among which the nurses who participated in the individual soldier standard in 2019 were the nurses who participated in the individual soldier standard in 2019 and 2020.A total of 29 people in the first batch were set as the control group,using traditional assessment methods.In 2020,the second batch of 29 nurses who participated in the individual soldier standard reached the experimental group.Using the video assessment method,there was no significant difference in general information between the two groups(P>0.05).After the assessment,the scores,coping with work pressure,and proactiveness of the two groups of research subjects were compared.Results:The experimental group’s nursing operation assessment scores,coping with work pressure,and proactiveness were significantly better than those of the control group,the difference was statistically significant(P<0.05).Conclusion:The application of the video assessment method improves the passing rate of nurses’operational skills examination,enhances nurses’initiative in learning,reduces examination pressure,and can be accurately,timely,and safely applied to clinical nursing work,which is worthy of study and promotion. 展开更多
关键词 Video assessment method NURSE operation skills Effect observation
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Research and Practice of the Blended Teaching Model of BOPPPS Teaching Method Under the Background of Digital Education: Taking Operations Research Course as an Example
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作者 Yan Wu 《Journal of Contemporary Educational Research》 2024年第6期155-160,共6页
The rapid development of digital education provides new opportunities and challenges for teaching model innovation.This study aims to explore the application of the BOPPPS(Bridge-in,Objective,Pre-assessment,Participat... The rapid development of digital education provides new opportunities and challenges for teaching model innovation.This study aims to explore the application of the BOPPPS(Bridge-in,Objective,Pre-assessment,Participatory learning,Post-assessment,Summary)teaching method in the development of a blended teaching model for the Operations Research course under the background of digital education.In response to the characteristics of the course and the needs of the student group,the teaching design is reconstructed with a student-centered approach,increasing practical teaching links,improving the assessment and evaluation system,and effectively implementing it in conjunction with digital educational technology.This teaching model has shown significant effectiveness in the context of digital education,providing valuable experience and insights for the innovation of the Operations Research course. 展开更多
关键词 Digital education BOPPPS teaching method Blended teaching model operations research
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EFFECT OF DIFFERENT OPERATION METHODS ON METHANE HYDRATE FORMATION 被引量:3
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作者 HAO Wenfeng~(1,2), FAN Shuanshi~2 and WANG Jinqu~1 (~1 Institute of Adsorption and Inorganic Membrane, Dalian University of Technology, Dalian 116012, Liaoning, China ~2 Guangzhou Institute of Energy Canversion, The Chinese Academy of Sciences, Guangzhou 510070, Guangdong, China) 《化工学报》 EI CAS CSCD 北大核心 2003年第z1期33-36,共4页
Three experiments of static state storage method, low-temperature and constant-pressure storage method and low-temperature and constant-pressure storage method were carried out to investigate which method was best in ... Three experiments of static state storage method, low-temperature and constant-pressure storage method and low-temperature and constant-pressure storage method were carried out to investigate which method was best in gas hydrate. The relationships of hydrate rate, capacity and liquid temperature versus time were derived and three results were contrasted. The experimental results show lowtemperature and constant-pressure method is better than the other two methods because it's operation period is shorter and storage capacity is larger than the other two. Low-temperature and constant-pressure method is the best method. So new method will be new research objective. 展开更多
关键词 effect operation method methane hydrate FORMATION
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Euler’s First-Order Explicit Method–Peridynamic Differential Operator for Solving Population Balance Equations of the Crystallization Process
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作者 Chunlei Ruan Cengceng Dong +2 位作者 Kunfeng Liang Zhijun Liu Xinru Bao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期3033-3049,共17页
Using Euler’s first-order explicit(EE)method and the peridynamic differential operator(PDDO)to discretize the time and internal crystal-size derivatives,respectively,the Euler’s first-order explicit method–peridyna... Using Euler’s first-order explicit(EE)method and the peridynamic differential operator(PDDO)to discretize the time and internal crystal-size derivatives,respectively,the Euler’s first-order explicit method–peridynamic differential operator(EE–PDDO)was obtained for solving the one-dimensional population balance equation in crystallization.Four different conditions during crystallization were studied:size-independent growth,sizedependent growth in a batch process,nucleation and size-independent growth,and nucleation and size-dependent growth in a continuous process.The high accuracy of the EE–PDDO method was confirmed by comparing it with the numerical results obtained using the second-order upwind and HR-van methods.The method is characterized by non-oscillation and high accuracy,especially in the discontinuous and sharp crystal size distribution.The stability of the EE–PDDO method,choice of weight function in the PDDO method,and optimal time step are also discussed. 展开更多
关键词 Population balance equation CRYSTALLIZATION peridynamic differential operator Euler’s first-order explicit method
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Satellite remote sensing of sea-ice and its operational monitoring method along the coast of China 被引量:3
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作者 Gong Jialong National Marine Environment Forecasting Center, SOA, Beijing. China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1989年第3期379-390,共12页
Sea-ice is an important operational item for real timely monitoring and forecasting marine environment of China. This paper introduces an operational method of satellite remote sensing to monitor sea- ice using quanti... Sea-ice is an important operational item for real timely monitoring and forecasting marine environment of China. This paper introduces an operational method of satellite remote sensing to monitor sea- ice using quantitative data of NOAA, and its contents include computer processing of AVHRR sounding data of NOAA and its program design, imagery processing of sea-ice imagery from satellite and their thematic analysis. The sea-ice satellite colour imageries processed via this software system are able to interpret sea-ice pattern, characterizing it by thickness, maximum position of ice boundary, floe concentration and dynamic process of ice changing. At the same time, analyses of the ice condition of the Bohai Sea for the two-year period (1986-1988) as monitored by satellite have been summarized. 展开更多
关键词 In Satellite remote sensing of sea-ice and its operational monitoring method along the coast of China
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From Knowledge Transfer to Capability Development:The Future of PBL+CBL Teaching Method in Operating Room Nursing Education
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作者 Kun Zhu Jiao Zhou +3 位作者 Yaqing Cui Zhengyan Shi Juntao Li Jia Li 《Journal of Contemporary Educational Research》 2024年第10期185-191,共7页
Concomitant with the advancement of contemporary medical technology,the significance of perioperative nursing has been increasingly accentuated,necessitating elevated standards for the pedagogy of perioperative nursin... Concomitant with the advancement of contemporary medical technology,the significance of perioperative nursing has been increasingly accentuated,necessitating elevated standards for the pedagogy of perioperative nursing.Presently,the PBL(problem-based learning)pedagogical approach,when integrated with CBL(case-based learning),has garnered considerable interest.An extensive literature review has been conducted to analyze the application of the PBL-CBL fusion in the education of perioperative nursing.Findings indicate that this integrative teaching methodology not only enhances students’theoretical knowledge,practical competencies,and collaborative skills but also contributes to the elevation of teaching quality.In conclusion,the PBL-CBL teaching approach holds immense potential for broader application in perioperative nursing education.Nevertheless,it is imperative to continually refine this combined pedagogical strategy to further enhance the caliber of perioperative nursing instruction and to cultivate a greater number of exceptional nursing professionals in the operating room setting. 展开更多
关键词 Knowledge transfer Capability development PBL+CBL teaching method operating room nursing EDUCATION
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Research on Controlled Volume Operation Method of Large-scale Water Transfer Canal
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作者 DING Zhiliang WANG Changde +1 位作者 XU Duo XIAO Hua 《Journal of Northeast Agricultural University(English Edition)》 CAS 2011年第3期47-59,共13页
The controlled volume method of operation is especially suitable for large-scale water delivery canal system with complex operation requirements. An operating simulation model based on the storage volume control metho... The controlled volume method of operation is especially suitable for large-scale water delivery canal system with complex operation requirements. An operating simulation model based on the storage volume control method for multi-reach canal system in series was established. In allusion to the deficiency of existing controlled volume algorithm, the improved controlled volume algorithm of the whole canal pools was proposed, and the simulation results indicated that the storage volume and water level of each canal pool could be accurately controlled after the improved algorithm had been adopted. However, for some typical discharge demand operating conditions, if the previously mentioned algorithm was adopted, then it certainly would cause some unnecessary gate adjustments, and consequently the disturbed canal pools would be increased. Therefore, the idea of controlled volume operation method of continuous canal pools was proposed, and corresponding algorithm was designed. Through simulating practical project, the results indicated that the new controlled volume algorithm proposed for typical operating conditions could comparatively and obviously reduce the number of regulated check gates and disturb canal pools for some typical discharge demand operating conditions, thus the control efficiency of canal system could be improved. 展开更多
关键词 canal operation controlled volume method of operation control algorithm SIMULATION
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Tide forecasting method based on dynamic weight distribution for operational evaluation
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作者 Shao-wei QIU Zeng-chuan DONG +2 位作者 Fen XU Li SUN Sheng CHEN 《Water Science and Engineering》 EI CAS 2009年第1期25-31,共7页
Through analysis of operational evaluation factors for tide forecasting, the relationship between the evaluation factors and the weights of forecasters was examined. A tide forecasting method based on dynamic weight d... Through analysis of operational evaluation factors for tide forecasting, the relationship between the evaluation factors and the weights of forecasters was examined. A tide forecasting method based on dynamic weight distribution for operational evaluation was developed, and multiple-forecaster synchronous forecasting was realized while avoiding the instability cased by only one forecaster. Weights were distributed to the forecasters according to each one's forecast precision. An evaluation criterion for the professional level of the forecasters was also built. The eligibility rates of forecast results demonstrate the skill of the forecasters and the stability of their forecasts. With the developed tide forecasting method, the precision and reasonableness of tide forecasting are improved. The application of the present method to tide forecasting at the Huangpu Park tidal station demonstrates the validity of the method. 展开更多
关键词 tide forecasting method operational evaluation dynamic weight distribution evaluation factor
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Research on resonance parameters matching based on partitioned operation method of atmospheric pressure plasma reactor array
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作者 Zhe YU Jialin ZHAO +3 位作者 Rui LIU Huijuan CAO Pu LIU Zhitao ZHANG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第5期34-42,共9页
Matching optimization of resonant parameters among the high power inverters,low power transformers and plasma reactors have significant effects on the performance and output of the reactor array when applying the part... Matching optimization of resonant parameters among the high power inverters,low power transformers and plasma reactors have significant effects on the performance and output of the reactor array when applying the partitioned operation method.In this paper,the Matlab/Simulink electrical model was established based on the method of partitioned operation.The matching relation between resonant parameters is analyzed on the basis of experimental result.As a consequence,transformer leakage inductance and working frequency are the important parameters influencing the operational efficiency of system,leakage inductance of transformer should be adjusted based on the equivalent capacitance of plasma reactor to realize the matching optimization of resonant parameters. 展开更多
关键词 ATMOSPHERIC pressure plasma reactor dielectric BARRIER DISCHARGE MATLAB/SIMULINK RESONANCE parameters partitioned operation method
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An Operational Test Method for VSC-HVDC Valves Based on Modular Multi-level Converters 被引量:12
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作者 WU Yanan LU Tianguang +2 位作者 TANG Guangfu ZHA Kunpeng GAO Chong 《中国电机工程学报》 EI CSCD 北大核心 2012年第30期I0002-I0002,4,共1页
为给基于模块化多电平换流器(modular multi-levelconverter,MMC)的电压源换流器高压直流输电(voltagesourced converter HVDC,VSC-HVDC)换流阀提供有效的检验手段,以验证其设计的正确性及其运行可靠性,对换流阀的运行特性和关键应... 为给基于模块化多电平换流器(modular multi-levelconverter,MMC)的电压源换流器高压直流输电(voltagesourced converter HVDC,VSC-HVDC)换流阀提供有效的检验手段,以验证其设计的正确性及其运行可靠性,对换流阀的运行特性和关键应力进行分析,提出基于原理等效的MMC阀运行试验方法,设计试验电路并阐明其运行机理。搭建的PSCAD电磁暂态仿真模型和实际的试验验证证明了试验方法的正确性和有效性。 展开更多
关键词 运行测试 多电平变换器 模块化 阀门 试验方法 高压直流输电 电平转换器 AC-DC
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Operational Methods for Ships in Waves From Perspectives of Structure Health and Maneuvering Convenience
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作者 ZHOU Feng ZHOU Junwei +1 位作者 CHEN Yuli WANG Deling 《Journal of Shipping and Ocean Engineering》 2017年第3期100-107,共8页
Based on the stress-strain data collected by a CSSMAS (container ship structure monitoring and analyzing system) onboard a container vessel, stress-strain responses of the ship's structure in high wave were analyze... Based on the stress-strain data collected by a CSSMAS (container ship structure monitoring and analyzing system) onboard a container vessel, stress-strain responses of the ship's structure in high wave were analyzed and illustrated for the identification of reasonable safe course sections. Besides the ship's structure safety, the maneuvering convenience is also deemed as a main concern which influences the safety of vessels in heavy waves. In order to develop a comprehensive guidance in adverse weather condition, the basic requirements on maneuvering convenience for vessels in storm were further discussed. In combination of the two requirements, namely structure health and maneuvering convenience, a proposed operational method was thus developed, which was an amendment to the traditional navigational method for ship in extreme weather. At the end of this paper, an example of optimal course planning in bad weather was illustrated by using the operational method proposed. 展开更多
关键词 Structural health maneuvering convenience extreme weather operational method
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Study on Growing Enterprise Operation Profit Management Method
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作者 Wu Xiukui 《International Journal of Technology Management》 2014年第7期56-57,共2页
With the rapid development of economy and constant improvement of social market economy system, the trade between countries is becoming more frequent and the competition is more intensified. As the main body of econom... With the rapid development of economy and constant improvement of social market economy system, the trade between countries is becoming more frequent and the competition is more intensified. As the main body of economy market, enterprises' competition is also expanding and strengthening, and fierce competition makes the disadvantaged enterprise withdrawal and also promotes the new enterprise. But the growing enterprise wants to grow sturdily, which is affected by many factors. It needs to face many challenges and cope with various problems. Some problems may not be in place, and they can not find any guidance examples, and this needs enterprise to analyze and choose. Slightly careless, emerging enterprises will be nipped in the cradle. This paper analyzes the operation management mode for the growing enterprise, based on this, it finds out the operation concept and proper operation mode suitable for the long-term development of enterprise, inorder to provide help for relevant stat^t: 展开更多
关键词 growing enterprise operation profit management method RESEARCH
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Arithmetic Operations of Generalized Trapezoidal Picture Fuzzy Numbers by Vertex Method
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作者 Mohammad Kamrul Hasan Abeda Sultana Nirmal Kanti Mitra 《American Journal of Computational Mathematics》 2023年第1期99-121,共23页
In this article, we define the arithmetic operations of generalized trapezoidal picture fuzzy numbers by vertex method which is assembled on a combination of the (α, γ, β)-cut concept and standard interval analysis... In this article, we define the arithmetic operations of generalized trapezoidal picture fuzzy numbers by vertex method which is assembled on a combination of the (α, γ, β)-cut concept and standard interval analysis. Various related properties are explored. Finally, some computations of picture fuzzy functions over generalized picture fuzzy variables are illustrated by using our proposed technique. 展开更多
关键词 Picture Fuzzy Set Generalized Trapezoidal Picture Fuzzy Number γ β)-Cut Arithmetic operations Vertex method
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Symplectic partitioned Runge-Kutta method based onthe eighth-order nearly analytic discrete operator and its wavefield simulations 被引量:3
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作者 张朝元 马啸 +1 位作者 杨磊 宋国杰 《Applied Geophysics》 SCIE CSCD 2014年第1期89-106,117,118,共20页
We propose a symplectic partitioned Runge-Kutta (SPRK) method with eighth-order spatial accuracy based on the extended Hamiltonian system of the acoustic waveequation. Known as the eighth-order NSPRK method, this te... We propose a symplectic partitioned Runge-Kutta (SPRK) method with eighth-order spatial accuracy based on the extended Hamiltonian system of the acoustic waveequation. Known as the eighth-order NSPRK method, this technique uses an eighth-orderaccurate nearly analytic discrete (NAD) operator to discretize high-order spatial differentialoperators and employs a second-order SPRK method to discretize temporal derivatives.The stability criteria and numerical dispersion relations of the eighth-order NSPRK methodare given by a semi-analytical method and are tested by numerical experiments. We alsoshow the differences of the numerical dispersions between the eighth-order NSPRK methodand conventional numerical methods such as the fourth-order NSPRK method, the eighth-order Lax-Wendroff correction (LWC) method and the eighth-order staggered-grid (SG)method. The result shows that the ability of the eighth-order NSPRK method to suppress thenumerical dispersion is obviously superior to that of the conventional numerical methods. Inthe same computational environment, to eliminate visible numerical dispersions, the eighth-order NSPRK is approximately 2.5 times faster than the fourth-order NSPRK and 3.4 timesfaster than the fourth-order SPRK, and the memory requirement is only approximately47.17% of the fourth-order NSPRK method and 49.41% of the fourth-order SPRK method,which indicates the highest computational efficiency. Modeling examples for the two-layermodels such as the heterogeneous and Marmousi models show that the wavefields generatedby the eighth-order NSPRK method are very clear with no visible numerical dispersion.These numerical experiments illustrate that the eighth-order NSPRK method can effectivelysuppress numerical dispersion when coarse grids are adopted. Therefore, this methodcan greatly decrease computer memory requirement and accelerate the forward modelingproductivity. In general, the eighth-order NSPRK method has tremendous potential value forseismic exploration and seismology research. 展开更多
关键词 SYMPLECTIC partitioned RUNGE-KUTTA method NEARLY ANALYTIC DISCRETE operATOR Numerical dispersion Wavefield simulation
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A Nonlocal Operator Method for Partial Differential Equations with Application to Electromagnetic Waveguide Problem 被引量:38
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作者 Timon Rabczuk Huilong Ren Xiaoying Zhuang 《Computers, Materials & Continua》 SCIE EI 2019年第4期31-55,共25页
A novel nonlocal operator theory based on the variational principle is proposed for the solution of partial differential equations.Common differential operators as well as the variational forms are defined within the ... A novel nonlocal operator theory based on the variational principle is proposed for the solution of partial differential equations.Common differential operators as well as the variational forms are defined within the context of nonlocal operators.The present nonlocal formulation allows the assembling of the tangent stiffness matrix with ease and simplicity,which is necessary for the eigenvalue analysis such as the waveguide problem.The present formulation is applied to solve the differential electromagnetic vector wave equations based on electric fields.The governing equations are converted into nonlocal integral form.An hourglass energy functional is introduced for the elimination of zeroenergy modes.Finally,the proposed method is validated by testing three classical benchmark problems. 展开更多
关键词 Nonlocal operator method Variational principle Nonlocal operators Hourglass mode
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Lifetime Evaluating and the Effects of Operation Conditions on Automotive Fuel Cells 被引量:3
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作者 PEI Pucheng YUAN Xing +2 位作者 LI Pengcheng CHAO Pengxiang CHANG Qianfei 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2010年第1期66-71,共6页
Lifetime isone of the important indicators of automotive proton exchange membrane fuel cells. People used to evaluate the lifetime of vehicular fuel cells by laboratory tests or road tests that usually take thousands ... Lifetime isone of the important indicators of automotive proton exchange membrane fuel cells. People used to evaluate the lifetime of vehicular fuel cells by laboratory tests or road tests that usually take thousands hours even years. In order to achieve a rapid evaluation technique and to seek lifetime extension methods, a lifetime calculation formation was drawn out in consideration of the vehicle driving cycle and the working condition factors. Bench experiments were individually carried out on two fuel-cell stacks same as ones applied on vehicle, and the performance decay rates of the two stacks were obtained under four operation conditions of changing load cycle, start-stop cycle, idling and heavy load. As a result, the predicted lifetimes rather conform to the actual running status in road test. And the research on the fuel cell performance decay rates under different load conditions was also done. Consequently, an unexpected finding was discovered that operating under micro-current has an effect on recovering fuel cell performance. The vehicle fuel cell rapid assessment method only requires four laboratory tests of driving cycle, load cycle, idle operating conditions and heavy load conditions, and the whole process merely lasts less than 250 h. These experimental results can be used to predict the vehicular fuel cell lifetimes on various utility models or driving cycles, therefore to optimize the application model to prolong the fuel cell lifetime. Actually in the experiment, it has already been proved successfully that the fuel cell lifetime could be extended from 1 100 h to 2 600 h by optimizing operating mode. The quick evaluation method is helpful to develop extended life fuel cell and to deplete fuel cell for a longer time. 展开更多
关键词 Proton exchange membrane fuel cell fuel cell durability lifetime evaluating method operation conditions melioration.
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ITERATIVE REGULARIZATION METHODS FOR NONLINEAR ILL-POSED OPERATOR EQUATIONS WITH M-ACCRETIVE MAPPINGS IN BANACH SPACES 被引量:2
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作者 Ioannis K.ARGYROS Santhosh GEORGE 《Acta Mathematica Scientia》 SCIE CSCD 2015年第6期1318-1324,共7页
In this paper, a modified Newton type iterative method is considered for ap- proximately solving ill-posed nonlinear operator equations involving m-accretive mappings in Banach space. Convergence rate of the method is... In this paper, a modified Newton type iterative method is considered for ap- proximately solving ill-posed nonlinear operator equations involving m-accretive mappings in Banach space. Convergence rate of the method is obtained based on an a priori choice of the regularization parameter. Our analysis is not based on the sequential continuity of the normalized duality mapping. 展开更多
关键词 nonlinear ill-posed equations iterative regularization m-accretive operator Newton type method
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Backfill support's backfill and operation properties and evaluation 被引量:4
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作者 ZHANG Qiang DU Chang-long +3 位作者 ZHANG Ji-xiong WANG Jia-qi LI Meng QI Wen-yue 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第6期1524-1534,共11页
To ensure compacted backfilling, it is essential to ensure the reliability of the performance of a solid backfill support, key equipment for integrating backfilling and mining. To evaluate the backfilling performance ... To ensure compacted backfilling, it is essential to ensure the reliability of the performance of a solid backfill support, key equipment for integrating backfilling and mining. To evaluate the backfilling performance of a backfill support, the concept of backfill and operation properties is proposed in this study. Moreover, it is elaborated in terms of five aspects, namely, structural property, supporting property, tamping property, mechanical response property, and geological adaptation property, which are specifically reflected by 14 indexes including the supporting intensity and vertical roof gap. Seven separate evaluation indexes are selected to build a backfill and operation properties based system for evaluating the design schemes of the backfill support via a multi-index comprehensive evaluation method; then, the evaluation method and process together with measures to control the backfill and operation properties are proposed. By using this system, 11 schemes for optimizing the ZC5200/14.5/3 backfill support at Zhaizhen Coal Mine are evaluated, and scheme #10 is found to show superior vertical roof gap and other backfill and operation properties, thus demonstrating the reasonability of the evaluation system. On this basis, the backfill support research framework of designing initial scheme, optimizing design scheme, selecting the best evaluation indexes, evaluating optimizing scheme, and evaluating operation properties is built; this should serve as an important reference for further studies on the roof controlling performance of a backfill support. 展开更多
关键词 backfilling coal mining backfill and operation properties tamping force vertical roof gap horizontal roofgap evaluation method
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Operational impacts to residual stands following ground-based skidding in Hyrcanian Forest, northern Iran 被引量:1
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作者 Meghdad Jourgholami 《Journal of Forestry Research》 SCIE CAS CSCD 2012年第2期333-337,共5页
Hyrcanian (Caspian) Forest in northern Iran has a richness of biological diversity, with endemic and endangered species. The usage of ground-based skidding is well accepted practice for the extraction of timber from... Hyrcanian (Caspian) Forest in northern Iran has a richness of biological diversity, with endemic and endangered species. The usage of ground-based skidding is well accepted practice for the extraction of timber from the forest, but this operation has tended to cause the greatest environmental problems. The aims of the study were to evaluate and comparison of operational impacts, residual stand damage, regeneration, and to quantify these effects such as: the extent of the damage, wounding patterns, size and distribution after logging operations that utilized two different methods: short log and long log. A Timbetjack cable skidder was used and the study location was in the Kheyrud Forest. Post harvesting assessment of damage to the residual stand was compared along skid trail by 100% inventory method and also for the assessment of regeneration damage along winching strips. The results show that along winching strips the percentage of damage to the regeneration was 44% and 36%, while the tree damages along skid trails reached 2.3% and 4.1% in the short log and long log methods, respectively. The greatest average amount of damage to a bole occurred along the first 1 m up from the ground (97%) and also within 4 m of the skidder centerline (80%). These results show that the short log method causes less damage to the residual stand than the longog method. Tree location to skidder trail appears to have a significant effect on the number and height of scars on a tree. Well designed and constructed trails should be wide enough to allow wood extraction from the forest. Damage to the residual stand might be reduced by proper planning and training of logging crews. 展开更多
关键词 operational impacts forest harvesting method residual stand damage regeneration
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