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水下栅格化恒流远供系统可靠性分析方法
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作者 周学军 刘柯欣 +1 位作者 王希晨 张政 《海军工程大学学报》 CAS 北大核心 2022年第4期59-67,共9页
远程供电系统的可靠性问题是制约缆系海底观测网络大规模体系建设的瓶颈之一。因此,首先构建了基于恒流供电制式的栅格化远程供电系统可靠性基础模型,按照电流流通路径及各水下单元相互关系,将系统细分为不同的供电链路和链路段;然后,... 远程供电系统的可靠性问题是制约缆系海底观测网络大规模体系建设的瓶颈之一。因此,首先构建了基于恒流供电制式的栅格化远程供电系统可靠性基础模型,按照电流流通路径及各水下单元相互关系,将系统细分为不同的供电链路和链路段;然后,详细分析了各水下单元开路、短路故障状态对系统、供电链路以及观测设备的影响,有针对性地提出了系统基本可靠性、链路可靠性及观测设备供电可靠性的分析方法;最后,通过算例分析,验证了该可靠性分析方法,印证了水下恒流供电制式的优势,提出了水下恒流供电系统可靠性问题分析的建议。该研究结果能够为缆系海底观测网的建设规划与工程设计提供理论支撑。 展开更多
关键词 系统 栅格化电拓扑结构 可靠性分析
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7A52合金中化合物的形成及防止 被引量:4
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作者 刘丹超 唐剑 +3 位作者 韦志宏 李成利 牟大强 史贵山 《铝加工》 CAS 2005年第3期53-56,共4页
通过对7A52合金中的主要元素Mn等进行控制,辅以专门的供流系统,合理控制冷却强度等三大工艺参数,可以使7A52合金中的化合物不影响制品的加工性能,对提高制品的成材率有明显效果。
关键词 化合物 供流系统 冷却强度
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Influence of soil resistivity on stray current in power supply system of urban rail transit 被引量:2
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作者 CHEN Wanglong LI Yaning WANG Ye 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2022年第3期261-266,共6页
In order to explore the influence of soil resistivity on stray current in power supply system of urban rail transit,we establish an equivalent circuit model of the rail-to-ground structure based on resistance network ... In order to explore the influence of soil resistivity on stray current in power supply system of urban rail transit,we establish an equivalent circuit model of the rail-to-ground structure based on resistance network method first.After measuring the soil resistivity of a real subway system,a simulation model is established in Matlab to obtain the stray currents at different soil resistivities.Then the influence of soil resistivity on stray current is analyzed.Afterwards,to verify the rationality and reliability of the simulation model,we design a test circuit to measure the stray current and rail-to-ground voltage in a real subway system,and a comparison of the experimentally measured results and simulation results is presented.The results show that the stray current is the maximum when the soil resistivity is 211.57Ω·m;when the soil resistivity is 768.47Ω·m,the stray current is the minimum,that is,the smaller the soil resistivity,the greater the stray current.Therefore,the resistivity should be increased as much as possible when ramming the track foundation in urban rail transit system. 展开更多
关键词 urban rail transit power supply system stray current soil resistivity four-electrode method
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An integrated operation mode for green logistics of enterprises 被引量:1
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作者 Yu Chengxue Wu Chunyou Fan Yu 《Ecological Economy》 2006年第4期348-356,共9页
The integrated operation mode of green logistics is a new enterprise's logistics operation and management mode concerning, environment issues based on the traditional integrated mode. Through comparative study on the... The integrated operation mode of green logistics is a new enterprise's logistics operation and management mode concerning, environment issues based on the traditional integrated mode. Through comparative study on the integrated operation mode of logistics based on self.operation, the operation mode of an integrated logistics of enterprises based on TPL the green-supply chain management, and the operation mode of eco-iadustrial park (EIP), a relatively complete objective system structure is put forward for the integrated operation mode of green logistics of enterprises. Furthermore, the correspondent practical mode is also set up to help enterprises, especially for the manufacturing companies, not only improve the environment effectively, but support the technological framework for the enterprise's economic performance and social benefits in order to realize economic, social and environmental benefits are concerned. 展开更多
关键词 ENVIRONMENT Green logistics INTEGRATION Operational mode
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Modeling and Analysis of Data Dependencies in Business Process for Data-Intensive Services 被引量:1
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作者 yuze huang jiwei huang +1 位作者 budan wu junliang chen 《China Communications》 SCIE CSCD 2017年第10期151-163,共13页
With the growing popularity of data-intensive services on the Internet, the traditional process-centric model for business process meets challenges due to the lack of abilities to describe data semantics and dependenc... With the growing popularity of data-intensive services on the Internet, the traditional process-centric model for business process meets challenges due to the lack of abilities to describe data semantics and dependencies, resulting in the inflexibility of the design and implement for the processes. This paper proposes a novel data-aware business process model which is able to describe both explicit control flow and implicit data flow. Data model with dependencies which are formulated by Linear-time Temporal Logic(LTL) is presented, and their satisfiability is validated by an automaton-based model checking algorithm. Data dependencies are fully considered in modeling phase, which helps to improve the efficiency and reliability of programming during developing phase. Finally, a prototype system based on j BPM for data-aware workflow is designed using such model, and has been deployed to Beijing Kingfore heating management system to validate the flexibility, efficacy and convenience of our approach for massive coding and large-scale system management in reality. 展开更多
关键词 data-aware business process data-intensive services data dependency linear-time temporal logic(LTL) services computing
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Coupled Seepage and Heat Transfer Intake Model
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作者 吴君华 由世俊 +1 位作者 张欢 李海山 《Transactions of Tianjin University》 EI CAS 2009年第6期446-451,共6页
In the beach well intake system, heat is transferred from soil to fluid when seawater is filtered through the aquifer, providing higher temperature source water to the seawater source heat pump (SWHP) system in winter... In the beach well intake system, heat is transferred from soil to fluid when seawater is filtered through the aquifer, providing higher temperature source water to the seawater source heat pump (SWHP) system in winter. A 3-D coupled seepage and heat transfer model for studying beach well intake system is established by adopting the computer code FLUENT. Numerical results of this model are compared with the experimental results under the same conditions. Based on the experiment-verified coupled model, numerical simulation of the supply water tem-perature is studied over a heating season. Results show that the minimum temperature of supply water is 275.2 K when this intake system continuously provides seawater with flow rate of 35 m3/h to SWHP. Results also indicate that the supply water temperature is higher than seawater, and that the minimum temperature of supply water lags behind seawater, ensuring effective and reliable operation of SWHP. 展开更多
关键词 seawater source heat pump renewable energy seawater intake beach well
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Information System Functions for SmartGrid Management
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作者 Mila llieva-Obretenova 《Sociology Study》 2016年第2期96-103,共8页
The violently penetration of renewables in power supply network leads to situations, by which the offer exceeds the demand. Therefore, it is necessary to include a system for processes' management. SmartGrid is a pla... The violently penetration of renewables in power supply network leads to situations, by which the offer exceeds the demand. Therefore, it is necessary to include a system for processes' management. SmartGrid is a platform over the power supply network. It is represented with its network and services, which also have to be managed. The paper aims to show the second stage of SmartGrid management modeling. It meets heterogeneous requirements of the actors--subscriber without photovoltaics, subscriber with photovoltaics, service provider, network operator, and network elements operator--to service and network management and is oriented to functional areas, covering the life cycle of power supply service: Design, Planning, Installation, Provision, Configuration, Maintenance, Performance, Accounting, Buying Up, Security and Subscriber Control. Functional models for existing networks--telecommunications--are used and they are adapted to power supply. The results are illustrated with three functional areas for service management: Accounting, Buying Up, and Performance. The synthesis of network management functions and network element management functions are similar. 展开更多
关键词 SmartGrid functional areas service management network management network element management
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Overview of the Power Supply System on the HL-2A Tokamak
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《Southwestern Institute of Physics Annual Report》 2006年第1期86-89,共4页
This paper shows the R&D results of the power supply system in 2006, including the application of speed control assemblies of two 80 MVA MG sets, the modification of the exciting field system, the development of the ... This paper shows the R&D results of the power supply system in 2006, including the application of speed control assemblies of two 80 MVA MG sets, the modification of the exciting field system, the development of the new HV modulators in ECRH system, the update of several poloidal power supplies. It also presents the status of the power suppIy system in HL-2A experimental operation and foresees the power and energy requirements for new power supply system at HL-2M device. 展开更多
关键词 Speed control HV modulator DC convertor
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Research on logistics management system based on supply chain management
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作者 Yi Shi 《International Journal of Technology Management》 2013年第6期71-74,共4页
Generally, supply chain logistics is the unification of logistics, information flow and capital flow, logistics runs through the whole process of the supply chain. Logistics connects the individual enterprise in the s... Generally, supply chain logistics is the unification of logistics, information flow and capital flow, logistics runs through the whole process of the supply chain. Logistics connects the individual enterprise in the supply chain and it is the bond of mutual cooperation between enterprises. In that way, the logistics management becomes an important part of the supply chain management system naturally. However, it is not so long since the theory of supply chain management and logistics management put forward so they are still being refined. Besides, it is lack of green philosophy in the logistics management of the supply chain and effect of logistics on the environment and resource efficiency do not be considered synthetically. Yet, methods to solve the problem that customers return items and waste materials have been excluded from the enterprises and business strategy. With the awareness that people should protect the environment and conserve resources enhanced and governments increase the intensity of environmental regulations constraints, the theory and practice of green logistics management are valued by the foreign supply chain management and logistics management theory community and the business community gradually. 展开更多
关键词 logistics management system supply chain management product manufacturing.
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Research on Enterprise Logistics Management System based on Internet of Things
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作者 Liqiang Tang 《International Journal of Technology Management》 2014年第8期76-78,共3页
Through the analysis of the feasibility of using network technology and network technology in supply chain management system, the paper puts forward the design framework of supply chain management system based on the ... Through the analysis of the feasibility of using network technology and network technology in supply chain management system, the paper puts forward the design framework of supply chain management system based on the lntemet of things, describes the key technology of the system. The application of Intemet of things in the supply chain management system, that will realize the effective management of the whole supply chain; enhance the competitiveness of enterprises and the whole supply chain. 展开更多
关键词 The lntemet of things enterprise logistics ERP OPTIMIZATION
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Research on the Influence of RFID Technique on Modem Retail Logistics System under the Intemet of Things Background
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作者 Chert Limin 《International Journal of Technology Management》 2015年第11期43-45,共3页
In this paper, we conduct research on the influence of RFID technique on modern retail logistics system under the Internet of things background. The application of Intemet of things make its and related enterprises in... In this paper, we conduct research on the influence of RFID technique on modern retail logistics system under the Internet of things background. The application of Intemet of things make its and related enterprises in the supply chain synchronization integration in the process, timely access to relevant information, understand the real needs of the market, the effective control of each link of the supply chain inventory quantity and effectively reduce the supply chain inventory and capital takes up between cooperative enterprises. Thus, in effectively improve the efficiency of the original system at the same time also save the cost of the supply chain management. With the combination of the RFID technique, we finalize the implementation of the logistics information and automation, automatic identification and inspection of finished goods inspection, greatly reduce the human capital, simplify the acceptance of goods and reduce the cost of handling times and human factors caused losses. In the final part, we conclude the work and propose our prospect. 展开更多
关键词 RFID Technique Modern Retail Logistics System Internet of Things Optimization.
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Experimental Study of Operation Performance for Hydrocarbon Fuel Pump with Low Specific Speed 被引量:1
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作者 WU Xianyu YANG Jun JIN Xuan 《Journal of Thermal Science》 SCIE EI CAS CSCD 2017年第5期440-447,共8页
In this paper, a small flow rate hydrocarbon turbine pump was used to pressurize the fuel supply system of scramjet engine. Some experiments were carried out to investigate the characteristics of turbine pump driven b... In this paper, a small flow rate hydrocarbon turbine pump was used to pressurize the fuel supply system of scramjet engine. Some experiments were carried out to investigate the characteristics of turbine pump driven by nitrogen or combustion gas under different operating conditions. A experimental database with regard to the curves of the rotational speed, mass flow rate and net head with regard to centrifugal pump were plotted. These curves were represented as functions of the pressure and temperature at turbine inlet/outlet and the throttle diameter at downstream of centrifugal pump. A sensitivity study has been carried out based on design of experiments. The experimental was employed to analyze net head of centrifugal and throttle characteristics. The research results can accumulate foundations for the close loop control system of turbine pump. 展开更多
关键词 expansion cycle scram jet hydrocarbon fuel turbo-pump operation performance
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Identification of Key Ecosystem Services That Can Be Delivered by Water or Wind from Zhangjiakou-Chengde Region to Beijing 被引量:1
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作者 LI Qingxu ZHANG Biao +1 位作者 XIE Gaodi WANG Shuang 《Journal of Resources and Ecology》 CSCD 2018年第6期632-641,共10页
Rapid urbanization causing serious air pollution and ecological risks in the Beijing–Tianjin–Hebei region in North China has attracted worldwide attention. This study estimates the key ecosystem services of land cov... Rapid urbanization causing serious air pollution and ecological risks in the Beijing–Tianjin–Hebei region in North China has attracted worldwide attention. This study estimates the key ecosystem services of land covers in Zhangjiakou and Chengde, and analyzes their main contributions and the effects of ecosystem service flows to Beijing. Results indicated that the total economic value of key ecosystem services in the Zhangjiakou–Chengde region was CNY 189.5 billion in 2013, and that these services were generated mainly from the forestlands, grasslands, and farmlands of Chengde and the eastern region of Zhangjiakou. However, nearly half of land covers provided low ecosystem service values and thus should be enhanced. In addition, approximately 21% of key ecosystem services were delivered from the Zhangjiakou–Chengde region into Beijing, and the flow feasibilities of ecosystem services delivered by water and wind reached 34% and 12%, respectively. Chicheng, Zhuolu, Chongli, Huailai, Xuanhua and Guyuan counties contributed 61% of the ecosystem services flowing into Beijing, and each service showed high regional relationships with Beijing(flow index ≥ 40%). Thus, these services should be prioritized in terms of ecological compensation funds and policies from Beijing. 展开更多
关键词 key ecosystem service supply and flow land cover Beijing-Tianjin-Hebei region Zhangjiakou-Chengde region
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Multi-reservoir joint operating rule in inter-basin water transfer-supply project 被引量:9
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作者 PENG AnBang PENG Yong +1 位作者 ZHOU HuiCheng ZHANG Chi 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2015年第1期123-137,共15页
The joint operation of inter-basin water transfer-supply(IBWTS)project can be more complex when there is joint water demand in multi-reservoir system and multi-importing reservoirs simultaneously transferring water fr... The joint operation of inter-basin water transfer-supply(IBWTS)project can be more complex when there is joint water demand in multi-reservoir system and multi-importing reservoirs simultaneously transferring water from exporting reservoir.In this study,a joint operating rule is proposed for the purpose of solving such complex operation problem.This rule is composed of a set of sub-rules,including hedging rule curves of virtual aggregation reservoir(i.e.equivalent reservoir)and other individual reservoirs,water-transfer rule curves of each individual reservoir,as well as some of important assisted rules.These assisted rules refer to allocation models for water transfer-supply.In the proposed rule,an equivalent reservoir is established to determine under what condition the water supply should be reduced and specify the total supplied water for joint water demand(i.e.aggregation method).Allocation models are developed to distribute the total transferred water into each importing reservoir and determine the water releases for joint water demand by each member reservoir of the aggregation system(i.e.decomposition method).And these models are integrated with a set of influence factors such as hydrologic characteristics,reservoir storage or vacant storage,regulating ability,water-supply pressure,and so on.The aggregation of multi-reservoirs and the disaggregation of water quantities are taken into a whole consideration to reduce the complexity in reallocation of water target storage or water release.Finally,the proposed rule is applied to the North-line IBWTS Project in Liaoning Province,China.The results indicate that the proposed rule can take full advantage of hydrologic compensation in basins and capacity compensation in reservoirs.Thus it can improve the utilization efficiency of water resources in system. 展开更多
关键词 inter-basin water transfer joint operating rule equivalent reservoir water-transfer allocation water-supply allocation
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