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Intelligent modeling and optimization on time-sharing power dispatching system for electrolytic zinc process 被引量:2
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作者 王雅琳 桂卫华 +1 位作者 阳春华 黄泰松 《中国有色金属学会会刊:英文版》 CSCD 2000年第4期561-565,共5页
Based on real time price counting of electric power, an optimization model of time sharing power for electrolytic zinc process(EZP) was established by means of an incremental fuzzy neural network(FNN), which is adopte... Based on real time price counting of electric power, an optimization model of time sharing power for electrolytic zinc process(EZP) was established by means of an incremental fuzzy neural network(FNN), which is adopted to approximate the relationship of current efficiency, current density and acidity. Penalty function introduced and optimal objective function reconstructed, a single loop simulated annealing algorithm(SAA) by using mutation and extending searching spaces was used to obtain optimal time sharing power scheme. Industrial practical results show that the whole system can greatly decrease the power consumption of EZP and increase the time sharing profits. 展开更多
关键词 FUZZY NEURAL network optimization model of time sharing POWER SIMULATED ANNEALING algorithm
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Share Time活动的开展与学生的主体发展
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作者 魏惠 《基础教育外语教学研究》 2008年第4期55-57,共3页
依据新课程确立学生主体地位的理念,针对本地中小学英语教学实际,笔者提出在Share Time活动中发展学生技能的英语学习方式。活动以话题为主要媒体,以个人、对子或小组为活动呈现方式,通过倾听、交流、协作、分享,从体验、表现、发... 依据新课程确立学生主体地位的理念,针对本地中小学英语教学实际,笔者提出在Share Time活动中发展学生技能的英语学习方式。活动以话题为主要媒体,以个人、对子或小组为活动呈现方式,通过倾听、交流、协作、分享,从体验、表现、发展的角度,在常规授课之外,让学生最大限度地发展自己的学习空间,展示学习、生活和心智特征的活动过程。 展开更多
关键词 SHARE time活动 学生 主体发展
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A time-sharing multi-channel pulse amplitude analyzer 被引量:2
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作者 Lian-Jun Jiang Xiang Zhou +1 位作者 Tong-Yu Wu Ze-Jie Yin 《Nuclear Science and Techniques》 SCIE CAS CSCD 2017年第4期91-96,共6页
A conventional multi-channel pulse amplitude analyzer acquires single energy spectrum,but provides no information on its tendency with time.To address the limitation,we propose a scheme of time-sharing multichannel pu... A conventional multi-channel pulse amplitude analyzer acquires single energy spectrum,but provides no information on its tendency with time.To address the limitation,we propose a scheme of time-sharing multichannel pulse amplitude analyzer(TSMCA).A dual-port random access memory is divided into two storage spaces,one for current energy spectrum data acquisition and another for previous energy spectrum data storage.The two tasks can be performed simultaneously,and the time-related variation tendency of energy spectrum can be obtained.A prototype system of TSMCA is designed.It performs nicely,with maximum channel number of 4096 in capacity of 2^(32)/Ch,minimal time-sharing slice of 25 ms,the differential nonlinearity of <1.5%,and the integral nonlinearity of <0.3%. 展开更多
关键词 MULTI-CHANNEL pulse AMPLITUDE ANALYZER MCA time-sharing ADC DUAL-PORT RAM
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Driving Mechanism of Cotton Comber's Detaching Roller Based on Time-Sharing Unidirectional Drive 被引量:3
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作者 李新荣 蒋秀明 +1 位作者 王生泽 王晓维 《Journal of Donghua University(English Edition)》 EI CAS 2014年第4期429-432,共4页
The high-speed reciprocating motion of a detaching roller limits the velocity of a cotton comber and affects the quality of comber slivers. The article has proposed a controllable time-sharing unidirectional hybrid dr... The high-speed reciprocating motion of a detaching roller limits the velocity of a cotton comber and affects the quality of comber slivers. The article has proposed a controllable time-sharing unidirectional hybrid drive mechanism after analyzing detaching roller's current numerical control drive method. The analysis focuses on the detaching roller motion required according to cotton comber's velocity and process. The double-servo motors of the mechanism consists of differential gear trains. The mechanism addresses the problem of increased servo motor power,and failure of promptly responded to the positive inversion process of mechanism driven by servo motors. A velocity calculation model of the detaching roller controllable drive mechanism will be generated by using superposition method and design of differential gear trains. The accuracy of the model will be verified using the test platform. This study has presented a reliable and practical high-speed drive mechanism and can be a reference to future studies on high-speed reciprocating motion drive. 展开更多
关键词 cotton comber detaching roller time-sharing unidirectional drive hybrid drive differential gear train
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Timed Petri Net Models of Shared-Memory Bus-Based Multiprocessors 被引量:1
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作者 Wlodek M. Zuberek 《Journal of Computer and Communications》 2018年第10期1-14,共14页
In shared-memory bus-based multiprocessors, when the number of processors grows, the processors spend an increasing amount of time waiting for access to the bus (and shared memory). This contention reduces the perform... In shared-memory bus-based multiprocessors, when the number of processors grows, the processors spend an increasing amount of time waiting for access to the bus (and shared memory). This contention reduces the performance of processors and imposes a limitation of the number of processors that can be used efficiently in bus-based systems. Since the multi-processor’s performance depends upon many parameters which affect the performance in different ways, timed Petri nets are used to model shared-memory bus-based multiprocessors at the instruction execution level, and the developed models are used to study how the performance of processors changes with the number of processors in the system. The results illustrate very well the restriction on the number of processors imposed by the shared bus. All performance characteristics presented in this paper are obtained by discrete-event simulation of Petri net models. 展开更多
关键词 SHARED-MEMORY MULTIPROCESSORS BUS-BASED MULTIPROCESSORS timeD PETRI NETS Discrete-Event Simulation
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Research on Real-time Data Sharing in Power Integrated Automation System
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作者 Zhaodong Wang Xiangjun Liu Qianqian Wu 《Energy and Power Engineering》 2013年第4期474-478,共5页
The Power Integrated Automation System has a large amount of the real-time data, it needs to achieve data sharing in different modules in its own system, sometimes even needs to be shared with the other systems. The t... The Power Integrated Automation System has a large amount of the real-time data, it needs to achieve data sharing in different modules in its own system, sometimes even needs to be shared with the other systems. The thesis discusses the characteristics and the ways of the real-time data sharing in the first place. Then, it compares the merits and drawbacks in different ways. Besides, it gives a viable resolution in different aspects, such as the design of the real-time database, the framework of the communication system and the design of the communication software, as well as the real-time data sharing in different systems. 展开更多
关键词 POWER Integrated Automotive STYLE sharing REAL-time DATABASE DCOM
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利用 TIMER 函数实现微机的分时控制
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作者 高丽佳 曹爱国 《沈阳建筑工程学院学报》 1997年第2期157-159,共3页
阐述如何利用QuickBASIC的TIMER函数实现微机的分时控制及在实际应用中应注意的几个问题
关键词 分时控制 A/D转换 脱机打印 事件 微机
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Optimal Energy-Efficient Transmission for Hybrid Spectrum Sharing in Cooperative Cognitive Radio Networks 被引量:9
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作者 Linna Hu Rui Shi +3 位作者 Minghe Mao Zhiyu Chen Hongxi Zhou Weiliang Li 《China Communications》 SCIE CSCD 2019年第6期150-161,共12页
In order to improve the energy efficiency(EE)in cognitive radio(CR),this paper investigates the joint design of cooperative spectrum sensing time and the power control optimization problem for the secondary user syste... In order to improve the energy efficiency(EE)in cognitive radio(CR),this paper investigates the joint design of cooperative spectrum sensing time and the power control optimization problem for the secondary user systems to achieve the maximum energy efficiency in a cognitive network based on hybrid spectrum sharing,meanwhile considering the maximum transmit power,user quality of service(QoS)requirements,interference limitations,and primary user protection.The optimization of energy efficient sensing time and power allocation is formulated as a non-convex optimization problem.The Dinkelbach’s method is adopted to solve this problem and to transform the non-convex optimization problem in fractional form into an equivalent optimization problem in the form of subtraction.Then,an iterative power allocation algorithm is proposed to solve the optimization problem.The simulation results show the effectiveness of the proposed algorithms for energy-efficient resource allocation in the cognitive network. 展开更多
关键词 cognitive radio networks COOPERATIVE SPECTRUM SENSING ENERGY-EFFICIENCY HYBRID SPECTRUM sharing power control SENSING time optimization
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Linux 2.6内核的Fair-Share调度算法研究
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作者 熊政 杨光友 《湖北工业大学学报》 2008年第5期18-20,共3页
分析了Linux 2.6内核的调度策略以及Fair-Share调度算法,通过修改Linux 2.6内核源码实现Fair-Share算法,实验表明,修改的算法具有较好的应用效果.
关键词 LINUX 进程调度 时间片 Fair-Share
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A Subsection Shared Restoration Method for Long-Haul WDM Networks
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作者 贺辉 范戈 《Journal of Shanghai Jiaotong university(Science)》 EI 2005年第1期44-47,共4页
A novel restoration scheme, Parted Path Shared Restoration (PPSR), was proposed. The major idea of PPSR is the strategy of ‘parted disposal’. PPSR keeps the advantage of Path Based Shared Restoration (PBSR) in utili... A novel restoration scheme, Parted Path Shared Restoration (PPSR), was proposed. The major idea of PPSR is the strategy of ‘parted disposal’. PPSR keeps the advantage of Path Based Shared Restoration (PBSR) in utilization of capacity. In addition, the restoration time of PPSR is much less than that of PBSR. Furthermore, a satisfaction function was proposed to estimate the performance of PPSR. This function takes the utilization of capacity and restoration time into a harmonious and uniform frame. Through theoretical analysis and computer simulation, the performance of PPSR was demonstrated. 展开更多
关键词 WDM networks parted shared restoration restoration time reserved capacity
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RELIABILITY ANALYSIS FOR A REPAIRABLE PARALLEL SYSTEM WITH TIME-VARYING FAILURE RATES 被引量:1
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作者 TangShengdao WangFengquan 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2005年第1期85-90,共6页
To solve a real problem:how to calculate the reliability of a system with time-varying failure rates in industry systems,this paper studies a model for the load-sharing parallel system with time-varying failure rates,... To solve a real problem:how to calculate the reliability of a system with time-varying failure rates in industry systems,this paper studies a model for the load-sharing parallel system with time-varying failure rates,and obtains calculating formulas of reliability and availability of the system by solving differential equations.In this paper,the failure rates are expressed in polynomial configuration.The constant,linear and Weibull failure rate are in their special form.The polynomial failure rates provide flexibility in modeling the practical time-varying failure rates. 展开更多
关键词 time-varying failure rates repairable parallel system Markov chain reliability and availability of system load-sharing.
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A Residual Time Based Scheduling: Performance Modeling in M/G/C Queueing Applications
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作者 Sarah Tasneem Lester Lipsky +1 位作者 Reda Ammar Howard Sholl 《Journal of Software Engineering and Applications》 2010年第8期746-755,共10页
It is well known, in queueing theory, that the system performance is greatly influenced by scheduling policy. No universal optimum scheduling strategy exists in systems where individual customer service demands are no... It is well known, in queueing theory, that the system performance is greatly influenced by scheduling policy. No universal optimum scheduling strategy exists in systems where individual customer service demands are not known a priori. However, if the distribution of job times is known, then the residual time (expected time remaining for a job), based on the service it has already received, can be calculated. Our particular research contribution is in exploring the use of this function to enhance system performance by increasing the probability that a job will meet its deadline. In a detailed discrete event simulation, we have tested many different distributions with a wide range of C2 and shapes, as well as for single and dual processor system. Results of four distributions are reported here. We compare with RR and FCFS, and find that in all distributions studied our algorithm performs best. In the study of the use of two slow servers versus one fast server, we have discovered that they provide comparable performance, and in a few cases the double server system does better. 展开更多
关键词 Simulation Residual time SCHEDULING Coefficient of Variation M/G/C QUEUE PROCESSOR sharing
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On Some Issues of Assessing the Efficiency of Renewable Energy Power Plants and the Share of Renewables in the World's Electricity Generation
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作者 Pavel Pavlovith Bezrukikh 《Journal of Electrical Engineering》 2018年第2期85-89,共5页
The paper considers some issues related to the evaluation of power plants using renewable energy sources: energy efficiency, economic efficiency, the share of renewable energy in the world's electricity generation. ... The paper considers some issues related to the evaluation of power plants using renewable energy sources: energy efficiency, economic efficiency, the share of renewable energy in the world's electricity generation. At one time in the world there was a myth that more energy is expended on the construction of wind and photoelectric power stations, than they produce for the service life. Adherents of this myth are still found in Russia. In response to this myth, numerous studies have been carried out for the manufacturers of wind turbines and photovoltaic modules. It was proved that these power plants spent energy on them are produced within a period of less than a year and the energy consumed by them cannot be taken into account, since it is renewable. The author showed that power plants on organic fuel and existing nuclear plants using depleted fuel with a coefficient less than unity fundamentally cannot compensate for the energy used during their construction. In the world, the concept of the LEC (Levelized Energy Cost) produced by any power plant is widely used to estimate economic efficiency. However, the formula for determining it, in the author's opinion, contains an inaccuracy, which is proposed to be eliminated. At present, there are different opinions on the role of RES (Renewable Energy Sources) in the production of electricity. A summary indicator is the share of renewable energy in the world's electricity generation. The determination of the actual share of RES and the forecast of its growth is of significant importance for the development of the world economy. The author shows the differences in the estimates and suggests an approach for establishing agreed estimates. 展开更多
关键词 Energy efficiency EPBT (energy payback time LEC growth rate weighted capacity factor share of RES in electricity production.
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M/S Controller Area Network(CAN) System Using Shared-Clock Scheduler
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作者 LIU Jianxin1,TAN Ping2,LIU Yu1 (1.School of Mechanical Engineering & Automation,Xihua University,Chengdu 610039,China 2.School of Mathematical & Computer Science,Xihua University,ChengDu 610039,China) 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S1期284-288,共5页
The Controller Area Network (CAN) is a well established control network for automotive and automation control applications. Time-Triggered Controller Area Network (TTCAN) is a recent development which introduces a ses... The Controller Area Network (CAN) is a well established control network for automotive and automation control applications. Time-Triggered Controller Area Network (TTCAN) is a recent development which introduces a session layer,for message scheduling,to the existing CAN standard,which is a two layer standard comprising of a physical layer and a data link layer. TTCAN facilitates network communication in a time-triggered fashion,by introducing a Time Division Multiple Access style communication scheme. This allows deterministic network behavior,where maximum message latency times can be quantified and guaranteed. In order to solve the problem of determinate time latency and synchronization among several districted units in one auto panel CAN systems,this paper proposed a prototype design implementation for a shared-clock scheduler based on PIC18F458 MCU. This leads to improved CAN system performance and avoid the latency jitters and guarantee a deterministic communication pattern on the bus. The real runtime performance is satisfied. 展开更多
关键词 time-TRIGGERED controller area network auto PANEL shared-clock SCHEDULER embedded SYSTEM
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人类命运共同体理念的建构历程及理论价值 被引量:2
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作者 于洋 《西北师大学报(社会科学版)》 CSSCI 北大核心 2024年第2期14-22,共9页
人类命运共同体理念是中国站在世界全局视角提出的顶层设计,是应对百年未有之大变局中全球性问题的中国答卷。中国对共同体的认识和发展根植于伟大的社会主义实践,深刻反映了中国革命、改革和建设中的诸多重大理论问题和现实问题,是对... 人类命运共同体理念是中国站在世界全局视角提出的顶层设计,是应对百年未有之大变局中全球性问题的中国答卷。中国对共同体的认识和发展根植于伟大的社会主义实践,深刻反映了中国革命、改革和建设中的诸多重大理论问题和现实问题,是对中国历年发展成果的经验总结,呈现出从实践到理论、再从理论到实践的辩证发展过程。人类命运共同体理念开辟了马克思主义中国化时代化新境界,是马克思主义立场、观点和方法的当代运用,凸显了马克思主义“实践是理论的源泉”的理论特质,是马克思“人的自由全面发展”思想的逻辑延续。人类命运共同体理念具有世界性,在继承中国优秀传统文化基因的基础上,凝聚人类文明新共识、形塑人类文明新形态。 展开更多
关键词 人类命运共同体 马克思主义中国化时代化 新型国际关系 全人类共同价值
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考虑健康信念的游客分时预约行为分析
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作者 韩艳 晋翎钰 +1 位作者 韩佳乔 关宏志 《北京工业大学学报》 CAS CSCD 北大核心 2024年第7期845-853,共9页
为探索新冠肺炎疫情背景下景区分时预约策略、游客健康信念和风险预防行为之间的关系,需考虑健康信念,分析疫情防控期间游客分时预约行为机理。采用意愿调查法获取旅游信息、健康信念、分时预约行为意向数据,分析各预约时段余票比例和... 为探索新冠肺炎疫情背景下景区分时预约策略、游客健康信念和风险预防行为之间的关系,需考虑健康信念,分析疫情防控期间游客分时预约行为机理。采用意愿调查法获取旅游信息、健康信念、分时预约行为意向数据,分析各预约时段余票比例和门票预售期等信息对游客分时预约行为的影响。基于Nested Logit(NL)模型,建立考虑健康信念的游客游玩日期-时段预约选择联合模型,并进行敏感性分析。结果表明:预约信息、健康信念对游客预约节假日或非节假日游玩有显著影响;票价、各预约时段余票比例和健康信念对游客游玩时段预约选择行为有显著影响。游客感知新冠的严重性由1上升至5时,选择节假日出行的概率由30.46%下降至12.28%。研究可为景区分时预约策略的制定提供参考依据。 展开更多
关键词 交通工程 分时预约选择联合模型 健康信念 Nested Logit(NL)模型 分时预约 敏感性分析
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考虑综合经济性的风光配电网储能优化配置 被引量:2
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作者 闫群民 李召 +2 位作者 马永翔 张芮华 张翔 《科学技术与工程》 北大核心 2024年第12期5014-5022,共9页
在配电网中配置储能系统可以有效缓解风光接入对配电网产生的影响,提升对风光的消纳能力、减少电压偏差等,而储能接入的位置和容量不同会对配电网产生不同的影响。首先分析储能建设过程中的主要费用,考虑基于分时电价下的网损成本和峰... 在配电网中配置储能系统可以有效缓解风光接入对配电网产生的影响,提升对风光的消纳能力、减少电压偏差等,而储能接入的位置和容量不同会对配电网产生不同的影响。首先分析储能建设过程中的主要费用,考虑基于分时电价下的网损成本和峰谷差收益,以年综合成本、配电网的日节点电压偏差和最小为目标,建立配电网储能选址定容模型,采用改进多目标遗传二代算法(improved multi-objective nondominated sorting genetic Ⅱ algorithm, INSGA-Ⅱ)对模型进行求解,利用改进理想点决策法(improved ideal point based decision, IIPBD)来选取最优配置方案,最后在IEEE-33节点模型中对方案进行验证。仿真结果表明:使用INSGA-Ⅱ算法进行求解时最终决策出的储能配置方案实现了成本最小,并且显著提升了电压的稳定性,验证了改进后算法的优良性和所提出的储能优化配置方案的有效性。 展开更多
关键词 配电网 储能系统 分时电价 改进多目标遗传二代算法(INSGA-Ⅱ) 改进理想点决策法(IIPBD)
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基于DE10_Lite的简易计算器实验
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作者 傅晓程 林平 张德华 《电气电子教学学报》 2024年第2期195-198,共4页
利用台湾友晶科技公司的DE10-Lite开发板上的资源,设计简易计算器,来实现4位10进制的加法、减法、乘法运算。利用开发板上十个拨动开关,两个按键开关,六个静态数码管,50 MHz信号,通过分层设计,顶层底层相结合、元件调用、实现简易计算... 利用台湾友晶科技公司的DE10-Lite开发板上的资源,设计简易计算器,来实现4位10进制的加法、减法、乘法运算。利用开发板上十个拨动开关,两个按键开关,六个静态数码管,50 MHz信号,通过分层设计,顶层底层相结合、元件调用、实现简易计算的分时显示,有利于学生自主设计能力培养。 展开更多
关键词 操作数 分时 状态机 调用
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面向质量和交货期的产能分享平台审核策略研究
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作者 赵道致 薛洋 韩红帅 《管理学报》 CSSCI 北大核心 2024年第8期1227-1236,共10页
通过构建双边市场模型探索产能分享平台的审核策略。研究表明:当产能需求方仅对质量敏感,排除低质量产能供应方比仅根据质量对产能供应方分级更利于平台盈利;当产能需求方对质量和交货期均敏感,设置两个维度的审核门槛能使平台获得更高... 通过构建双边市场模型探索产能分享平台的审核策略。研究表明:当产能需求方仅对质量敏感,排除低质量产能供应方比仅根据质量对产能供应方分级更利于平台盈利;当产能需求方对质量和交货期均敏感,设置两个维度的审核门槛能使平台获得更高利润;平台利润与双边用户交叉网络外部性、产能需求方对质量的敏感性正相关,与产能需求方对交货期的敏感性负相关;质量和交货期审核门槛受产能需求方对这两个维度的敏感性、双边用户网络外部性、平台审核成本系数相互作用影响。 展开更多
关键词 产能分享 平台审核 质量敏感 交货期敏感 交叉网络外部性
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含准Z源的双永磁电机驱动系统的研究及仿真
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作者 李军军 易吉良 李中启 《计算机仿真》 2024年第7期195-199,206,共6页
由于九开关逆变器通过共享模式,可减少电力电子器件数量,减小驱动装置的体积与重量,适用于双机驱动的应用场合。针对九开关逆变器双机驱动系统中单台电机电压利用率低的问题,研究了一种含准Z源的双永磁同步电机驱动系统。为了实现双机... 由于九开关逆变器通过共享模式,可减少电力电子器件数量,减小驱动装置的体积与重量,适用于双机驱动的应用场合。针对九开关逆变器双机驱动系统中单台电机电压利用率低的问题,研究了一种含准Z源的双永磁同步电机驱动系统。为了实现双机驱动系统中每台电机的独立可控,研究了基于SVPWM调制的双机分时控制原理。为满足不同的工况,研究了永磁同步电机的恒转矩-弱磁控制策略,利用间接电压法对Z源电压进行控制,以维持Z源电压的稳定。搭建了含准Z源的双永磁同步驱动系统仿真模型,仿真结果表明,永磁同步电机和准Z源的控制策略行之有效,分时控制可实现双机驱动系统的独立可控,可满足工程应用的需求。 展开更多
关键词 九开关逆变器 分时控制 永磁同步电机
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