期刊文献+
共找到10篇文章
< 1 >
每页显示 20 50 100
Realization and Analysis of Good Fuel Economy and Kinetic Performance of a Low-cost Hybrid Electric Vehicle 被引量:7
1
作者 WANG Lei ZHANG Jianlong YIN Chengliang ZHANG Yong WU Zhiwei 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第5期774-789,共16页
By using high-power and high-efficiency propulsion systems,current hybrid electric vehicles(HEVs) in market can achieve excellent fuel economy and kinetic performance.However,it is the cost of current HEVs that hind... By using high-power and high-efficiency propulsion systems,current hybrid electric vehicles(HEVs) in market can achieve excellent fuel economy and kinetic performance.However,it is the cost of current HEVs that hinders HEVs coming into widespread use.A novel hybrid electric propulsion system is designed to balance HEV cost and performance for developing markets.A battery/supercapacitor-based hybrid energy storage system(HESS) is used to improve energy conversion efficiency and reduce battery size and cost.An all-in-one-controller(AIOC) which integrates engine electronic control unit(ECU),motor ECU,and HESS management system is developed to save materials and energy,and reduce the influence of distribution parameters on circuit.As for the powertrain configuration,four schemes are presented:belt-driven starter generator(BSG) scheme,four-wheel drive HEV scheme,full HEV scheme,and ranger-extender electric vehicle(EV) scheme.Component selection and parameter matching for the propulsion system are performed,and an energy management strategy is developed based on powertrain configuration and selected components.Forward-facing simulation models are built,comprehending the control strategy based on the optimal engine torque for the low-cost hybrid electric propulsion system.Co-simulation of AVL CRUISE and Matlab/Simulink is presented and the best scheme is selected.The simulation results indicate that,for the best design,fuel consumption in urban driving condition is 4.11 L/(100 km) and 0-50 km/h accelerating time is 10.95 s.The proposed research can realize low-cost concept for HEV while achieving satisfactory fuel economy and kinetic performance,and help to improve commercialization of HEVs. 展开更多
关键词 low-cost hybrid electric vehicle hybrid energy storage system(HESS) fuel economy kinetic performance co-simulation cost and performance tradeoff
下载PDF
A novel model for cost performance evaluation of pulverized coal injected into blast furnace based on effective calorific value 被引量:4
2
作者 徐润生 张建良 +3 位作者 左海滨 李克江 宋腾飞 邵久刚 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第10期3990-3998,共9页
The combustion process of pulverized coal injected into blast furnace involves a lot of physical and chemical reactions. Based on the combustion behaviors of pulverized coal, the conception of coal effective calorific... The combustion process of pulverized coal injected into blast furnace involves a lot of physical and chemical reactions. Based on the combustion behaviors of pulverized coal, the conception of coal effective calorific value representing the actual thermal energy provided for blast furnace was proposed. A cost performance evaluation model of coal injection was built up for the optimal selection of various kinds of coal based on effective calorific value. The model contains two indicators: coal effective calorific value which has eight sub-indicators and coal injection cost which includes four sub-indicators. In addition, the calculation principle and application of cost performance evaluation model in a Chinese large-scale iron and steel company were comprehensively introduced. The evaluation results finally confirm that this novel model is of great significance to the optimal selection of blast furnace pulverized coal. 展开更多
关键词 blast furnace pulverized coal injection effective calorific value cost performance evaluation model
下载PDF
Integrated Control Model for Time and Cost Risk in Project Management
3
作者 程铁信 张伟波 张勇 《Transactions of Tianjin University》 EI CAS 2002年第2期99-105,共7页
Time, cost and quality are the three main targets to be controled in project management. However, the control and management of time and cost risk are usually carried out respectively, which will bring such problems a... Time, cost and quality are the three main targets to be controled in project management. However, the control and management of time and cost risk are usually carried out respectively, which will bring such problems as the delay of schedule by reason of the impracticability of cash flow, the money difficulties caused by delay of schedule and so on. In order to control and manage the time and cost risk effectively and simultaneously, a time & cost risk control model based on schedule programme was established with the use of the quantitativemodels of BCWS, BCWP and ACWP in this paper. Subsequently, the analysis of variance for the whole project and the single activity was introduced on the basis of BCWS, BCWP and ACWP so that the project can be controlled and managed effectively. Furthermore, an example given behind in detail expressly illustrated that the model set up above was practicableto project management. However, the method of optimizing the cash flow based on time and cost risk to obtain BCWS should be considered properlyand carefully with respect to the different circumstances of the project, and an efficient and adequate interval report system should be set up on the site of the project. 展开更多
关键词 project management budgeted cost of work performed (BCWP) actual cost work performed (ACWP) budget cost of workscheduled (BCWS)
下载PDF
A FAST SEAMLESS HANDOVER SCHEME AND ITS CDT OPTIMIZATION FOR PING-PONG TYPE OF MOVEMENT 被引量:3
4
作者 Wang Yumlng Yang Zongkai +2 位作者 Zhao Dasheng He Jianhua Fu Xiaoming 《Journal of Electronics(China)》 2006年第2期298-303,共6页
In mobile IPv6 networks, the ping-pong type of movement brings about frequent handovers and thus increases signaling burden. This letter proposes a fast seamless handover scheme where the access router keeps the mobil... In mobile IPv6 networks, the ping-pong type of movement brings about frequent handovers and thus increases signaling burden. This letter proposes a fast seamless handover scheme where the access router keeps the mobile node's old reservation till the offline Count Down Timer (CDT) expires in order to reduce handover signaling and delay while the mobile node returns in a very short period of time. Based upon a pois son mobility model, an simple expression for CDT optimization is given out for the scheme to achieve the best cost performance of resource reservation. 展开更多
关键词 Mobile IPv6 Ping-pong type of movement QoS signaling Handover delay Cost performance.
下载PDF
Optimal use of mobile cooling units in a deep-level gold mine 被引量:1
5
作者 H.J.van Staden J.F.van Rensburg H.J.Groenewald 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2020年第4期547-553,共7页
The South African gold mining sector remains a significant contributor to the country’s economy.Facing several challenges that hinder the realisation of South Africa’s full mineral potential,the sector’s sustainabi... The South African gold mining sector remains a significant contributor to the country’s economy.Facing several challenges that hinder the realisation of South Africa’s full mineral potential,the sector’s sustainability and profitability can be enhanced through implementing operational improvement measures.Mobile cooling units(MCUs)were identified as a potential focus area for operational improvement.MCUs are used as tertiary or in-stope cooling in hot underground workings.In this paper,a method was presented to characterise the performance of existing MCUs based on three key performance indicators(KPIs),namely,the wet-bulb temperature ratio(WTR),efficiency and position.Optimisation strategies were then elected and implemented based on these KPIs.The implementation of this method in a South African gold mine attained a reduction in pumped water volumes,reduced operating costs through electricity cost savings and improvements in underground ventilation air temperatures. 展开更多
关键词 Mobile cooling units Optimisation Mine cooling performance Electricity cost savings Spot cooling
下载PDF
Performance of seven highway construction contracting methods analyzed by project size 被引量:1
6
作者 Yuanxin ZHANG Abdol CHINI +2 位作者 R.Edward MINCHIN Jr. Lourdes PTSCHELINZEW Dev SHAH 《Frontiers of Engineering Management》 2018年第2期240-250,共11页
The conventional Design-Bid-Build(DBB)construction contracting method has had various drawbacks exposed in highway construction practice, including lack of communication, inefficient design, antagonizing relationships... The conventional Design-Bid-Build(DBB)construction contracting method has had various drawbacks exposed in highway construction practice, including lack of communication, inefficient design, antagonizing relationships, and increased disputes. To mitigate the negative aspects of DBB, several alternative contracting methods and alternative project delivery systems have been devised and introduced to the industry over the past30 years. Five such innovations were tested by a research team from the University of Florida under the sponsorship of the Florida Department of Transportation(FDOT). To perform a realistic assessment, this study categorized FDOT projects built between 2006 and 2015 into groups according to current contract amounts. Both absolute and relative metrics were defined and employed. For comparison purposes, a collective analysis on all gathered data was performed. Additionally, the influence of outliers on the results was examined. The results showed that analyses based on individual cost categories are more convincing because large projects tend to impose stronger influence on the analyses. In addition, outliers must be identified and screened to reach realistic and reliable conclusions. With regard to the actual performance of the contracting methods, each performs differently within different cost categories. 展开更多
关键词 alternative contracting methods time cost performance evaluation
原文传递
Single-shot incoherent optical processing of microwave signals: opening the path to low cost high performance analog photonics
7
作者 Jose Capmany 《Science Bulletin》 SCIE EI CAS CSCD 2017年第9期652-653,共2页
Incoherent optical processing of microwave signals,where low-coherence broadband light sources are employed instead of costly mode locked lasers,has attracted great interest thanks to its wide applications in microwav... Incoherent optical processing of microwave signals,where low-coherence broadband light sources are employed instead of costly mode locked lasers,has attracted great interest thanks to its wide applications in microwave photonics filtering[1–3],arbitrary generation[4–6]and analog to digital conversion[7]。 展开更多
关键词 Single-shot incoherent optical processing of microwave signals:opening the path to low cost high performance analog photonics high MZM SNR mode SLD
原文传递
Study of Multi-objective Fuzzy Optimization for Path Planning 被引量:12
8
作者 WANG Yanyang WEI Tietao QU Xiangju 《Chinese Journal of Aeronautics》 SCIE EI CSCD 2012年第1期51-56,共6页
During path planning, it is necessary to satisfy the requirements of multiple objectives. Multi-objective synthesis is based on the need of flight mission and subjectivity inclination of decision-maker. The decision-m... During path planning, it is necessary to satisfy the requirements of multiple objectives. Multi-objective synthesis is based on the need of flight mission and subjectivity inclination of decision-maker. The decision-maker, however, has illegibility for under- standing the requirements of multiple objectives and the subjectivity inclination. It is important to develop a reasonable cost performance index for describing the illegibility of the decision-maker in multi-objective path planning. Based on Voronoi dia- gram method for the path planning, this paper studies the synthesis method of the multi-objective cost performance index. Ac- cording to the application of the cost performance index to the path planning based on Voronoi diagram method, this paper ana- lyzes the cost performance index which has been referred to at present. The analysis shows the insufficiency of the cost per- formance index at present, i.e., it is difficult to synthesize sub-objective flmctions because of the great disparity of the sub-objective fimctions. Thus, a new approach is developed to optimize the cost performance index with the multi-objective fuzzy optimization strategy, and an improved performance index is established, which could coordinate the weight conflict of the sub-objective functions. Finally, the experimental result shows the effectiveness of the proposed approach. 展开更多
关键词 flight paths path planning cost performance index synthesis of multi-objective fuzzy inference Voronoi diagram
原文传递
Development of New Type Mn-Series Bainitic Steels in China 被引量:1
9
作者 BAI Bing-zhe,GAO Gu-hui,ZHENG Yan-kang,YANG Zhi-gang (Key Laboratory of Advanced Materials of Ministry of Education,Department of Material Science and Engineering,Tsinghua University,Beijing 100084,China) 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2011年第S1期112-120,共9页
The alloying design idea,strengthening-toughening mechanism,microstructure,mechanical performances,development and application in China of new type Mn-series bainitic steels are introduced.Mn-series air-cooling bainit... The alloying design idea,strengthening-toughening mechanism,microstructure,mechanical performances,development and application in China of new type Mn-series bainitic steels are introduced.Mn-series air-cooling bainitic steels including granular bainitic steels,FGBA /BG duplex steels,CFB/M duplex steels,medium carbon bainite/martensite steels,cast bainitic steels are presented.The invented idea mechanical performances,development and application of second generation of Mn-series bainitic steels,i.e.water quenching Mn-series bainitic steels invented by the authors newly are introduced.The water quenching Mn-series bainitic steels cover severe series steels containing ultra-low carbon,low-low carbon,medium-low carbon,and high-low carbon content etc,which can reduce the amount of alloying content,increase hardening capability and improve weldability.It should be pointed out that the application of both air cooling and water quenching Mn-series bainitic steels are complementary and mutually reinforcing,and the new type Mn-series bainitic steels can meet the performance requirements of most steels used in engineering structure.Some newest technologies of Mn-series bainitic steels in China are discussed in this paper.It is suggested that the significance of the development of the Mn-series bainitic steels can be summarized as:significantly reducing costs of both raw materials and production;good combination of strength and toughness;excellent weldability;simple procedure;large savings in energy resources and reduced environmental pollution. 展开更多
关键词 bainitic steels strengthening-toughening mechanism low cost high performances air cooling bainitic steel water quenching bainitic steel
原文传递
Study on the optimization of the water Cherenkov detector array of the LHAASO project for surveying VHE gamma ray sources
10
作者 李会财 陈明君 +6 位作者 贾焕玉 高博 吴含荣 姚志国 游晓浩 周斌 祝凤荣 《Chinese Physics C》 SCIE CAS CSCD 2014年第1期49-55,共7页
It is prpopsed that a water Cherenkov detector array, LHAASO-WCDA, is to be built at Shangri-la, Yunnan Province, China. As one of the major components of the LHAASO project, the main purpose of it is to survey the no... It is prpopsed that a water Cherenkov detector array, LHAASO-WCDA, is to be built at Shangri-la, Yunnan Province, China. As one of the major components of the LHAASO project, the main purpose of it is to survey the northern sky for gamma ray sources in the energy range of 100 GeV-30 TeV. In order to design the water Cherenkov array efficiently to economize the budget, a Monte Carlo simulation is carried out. With the help of the simulation, the cost performance of different configurations of the array are obtained and compared with each other, serving as a guide for the more detailed design of the experiment in the next step. 展开更多
关键词 LHAASO-WCDA gamma rays source cost performance OPTIMIZATION
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部