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基于驱力系统障碍的企业组织创新风险分析 被引量:3
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作者 肖东生 《经济与管理研究》 CSSCI 北大核心 2002年第3期37-40,共4页
一、企业组织创新驱力要素回顾与审视 驱力源于需要,促使企业组织创新需要主要是追求规模经济,追求剩余权力和节省组织费用. 1.规模经济驱动论.指把追求规模扩大作为组织创新的驱力.最早涉及企业组织创新与规模经济关系这一命题的是马歇... 一、企业组织创新驱力要素回顾与审视 驱力源于需要,促使企业组织创新需要主要是追求规模经济,追求剩余权力和节省组织费用. 1.规模经济驱动论.指把追求规模扩大作为组织创新的驱力.最早涉及企业组织创新与规模经济关系这一命题的是马歇尔.他在1890年就认为改进组织可以导致规模效益的提高,"劳动和资本的增加,一般导致组织的改进,而组织的改进增大劳动和资本的使用效率"①. 展开更多
关键词 规模经济 核心竞争 委托代理关系 组织费用 驱力系统 企业 组织创新 风险分析
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Driving Forces and Their Effects on Water Conservation Services in Forest Ecosystems in China 被引量:11
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作者 GONG Shihan XIAO Yang +2 位作者 XIAO Yi ZHANG Lu OUYANG Zhiyun 《Chinese Geographical Science》 SCIE CSCD 2017年第2期216-228,共13页
Identifying the driving forces that cause changes in forest ecosystem services related to water conservation is essential for the design of interventions that could enhance positive impacts as well as minimizing negat... Identifying the driving forces that cause changes in forest ecosystem services related to water conservation is essential for the design of interventions that could enhance positive impacts as well as minimizing negative impacts. In this study, we propose an assessment concept framework model for indirect-direct-ecosystem service (IN-DI-ESS) driving forces within this context and method for index construction that considers the selection of a robust and parsimonious variable set. Factor analysis was integrated into two-stage data envelopment analysis (TS-DEA) to determine the driving forces and their effects on water conservation services in forest ecosystems at the provincial scale in China. The results showed the following. 1) Ten indicators with factor scores more than 0.8 were selected as the minimum data set. Four indicators comprising population density, per capita gross domestic product, irrigation efficiency, and per capita food consumption were the indirect driving factors, and six indicators comprising precipitation, farmland into forestry or pasture, forest cover, habitat area, water footprint, and wood extraction were the direct driving forces. 2) Spearman's rank correlation test was performed to compare the overall effectiveness in two periods: stage 1 and stage 2. The calculated coefficients were 0.245, 0.136, and 0.579, respectively, whereas the tabulated value was 0.562. This indicates that the driving forces obviously differed in terms of their contribution to the overall effectiveness and they caused changes in water conservation services in different stages. In terms of the variations in different driving force effects in the years 2000 and 2010, the overall, stage 1, and stage 2 variances were 0.020, 0.065, and 0.079 in 2000, respectively, and 0.018, 0.063, and 0.071 in 2010. This also indicates that heterogeneous driving force effects were obvious in the process during the same period. Identifying the driving forces that affect service changes and evaluating their efficiency have significant policy implications for the management of forest ecosystem services. Advanced effectiveness measures for weak regions could be improved in an appropriate manner. In this study, we showed that factor analysis coupled with TS-DEA based on the IN-D1-ESS framework can increase the parsimony of driving force indicators, as well as interpreting the interactions among indirect and direct driving forces with forest ecosystem water conservation services, and reducing the uncertainty related to the internal consistency during data selection. 展开更多
关键词 driving effectiveness driving force factor analysis forest ecosystem two-stage data envelopment analysis water conservation service
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The design analyze of new hybrid drive concept
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作者 Szumanowski Antoni Chang Yuhua 《High Technology Letters》 EI CAS 2010年第1期45-51,共7页
This paper presents the design method of hybrid drive system for the minibus with some limited conditions. The approach of design hybrid drive system is based on the dynamic modeling and simulation of the hybrid minib... This paper presents the design method of hybrid drive system for the minibus with some limited conditions. The approach of design hybrid drive system is based on the dynamic modeling and simulation of the hybrid minibus with planetary gear system. The main target of the design is to obtain the optimal design with the proper hybrid drive configuration and control for a given set of design constraints. In oder to meet the design target, it's necessary to adjust some parameters such as mechanical ratios and parameters of battery pack as well as control by simulation. During simulation the transient operating process can be studied in details with the dynamic model in Matlab/Simulink. The control strategy can be optimized by running the simulation and monitoring the operation of each components: the operating area of internal combustion engine (ICE), fuel consumption (energy consumption), the power distribution, the torque and rotary speed of ICE and motor, the operating efficiency of motor, the aheration of battery state of charge (SOC), current and voltage. 展开更多
关键词 hybrid drive vehicle POWERTRAIN SIMULATION vehicle performance energy consumption
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The dynamic running law study on driving system of hydraulic winder
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作者 彭佑多 刘德顺 +2 位作者 郭迎福 张永忠 文西芹 《Journal of Coal Science & Engineering(China)》 2002年第1期73-78,共6页
Dynamic running law of the hydraulic driving system decides the hoisting cage velocity curve in a hoisting cycle and is decided by the characteristic of the hydraulic driving system and by the operating speed of hoist... Dynamic running law of the hydraulic driving system decides the hoisting cage velocity curve in a hoisting cycle and is decided by the characteristic of the hydraulic driving system and by the operating speed of hoist driver. The paper studies the dynamic running law of hydraulic driving system, analyses the influence of driver operating speed on the dynamic running characteristic, and points out the reasonable driver operating speed to control the dynamic stress in rope and to reduce the oscillation of rope system. 展开更多
关键词 hydraulic winder driving system hoisting cage dynamic running characteristic driver operating speed
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Modern Multilevel Control Technique Used in Electric and Hybrid Drive System with Induction Motors
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作者 Zygmunt Szymanski 《Computer Technology and Application》 2012年第12期789-796,共8页
The mathematical model of the modem induction traction motor (TRIM and cutting magnetic circuit traction motor), supplied with IPM inverter with different control technique is presented in the paper. In electric and... The mathematical model of the modem induction traction motor (TRIM and cutting magnetic circuit traction motor), supplied with IPM inverter with different control technique is presented in the paper. In electric and hybrid vehicle are applied: FLMC (Fuzzy Logic Mode Control), SLMC (Sliding Mode Control), NRMC (Neural Regulator Control), and Direct Power and Torque Control for Space Vector Modulated inverter (DPTC SVM). In the special solution of the electric and hybrid vehicle are also applied a Random Switching Frequency Modulation. The control of hybrid vehicle should assure the realization of established transport-assignments in the definite time, at the optimum of energy consumption. One can this realize using. The multi criteria control system. Some results of the computer simulations are presented in the paper. Results of numerical calculation were verified for laboratory model of the electric and hybrid wheel vehicles traction motor. 展开更多
关键词 Induction motor multilevel control system hybrid drive system random control system.
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Quasi Dynamic Model of Wheel Vehicle with Electric and Hybrid Drive System
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作者 Zygmunt Szymanski 《Computer Technology and Application》 2013年第11期606-614,共9页
The paper presents physical and mathematical models of kinetic system, drive system (electric and combustion traction motors), and also wheel and rails traction vehicle supply system (car, special vehicle, modern t... The paper presents physical and mathematical models of kinetic system, drive system (electric and combustion traction motors), and also wheel and rails traction vehicle supply system (car, special vehicle, modern tram vehicle). Selected predictive and quasi dynamic control system algorithms of traction vehicle are presented in the paper. For selected constructions of traction vehicle drive system are presented in simulation models and are results of calculations of different exploitations work state of wheel vehicle with hybrid drive system. Results of computer calculations are verified with laboratory measurement and suitable corrections coefficient to simulations models of vehicles is introduced. 展开更多
关键词 Hybrid drive predictive control computer calculation.
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Basic Characteristics of the Hydraulic-Driven Forceps for Force Feedback
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作者 Tohru Sasaki Yasuyuki Mito +1 位作者 Mitsuru Jindai Yusuke Ikemoto 《Journal of Mechanics Engineering and Automation》 2015年第9期519-524,共6页
A surgical manipulator has widely been used for laparoscopic surgery. It has been chosen mainly for the use in supporting human operations and in robot systems like the da Vinci surgical system. These manipulator syst... A surgical manipulator has widely been used for laparoscopic surgery. It has been chosen mainly for the use in supporting human operations and in robot systems like the da Vinci surgical system. These manipulator systems are suitable for careful work, but they have a few problems. One of the problems is that the manipulator is not equipped with haptic sensing functions. Therefore, the operator must know the advanced techniques for visually detecting the physical contact state during surgical operations. These haptic sensing functions thus need to be incorporated into a surgical manipulator. We have developed hydraulic-driven forceps with a micro bearing and a bellows tube that can convey haptic sense to the operator. This system can measure the small forces acting on the tips of the forceps using Pascal's principle. A model of the system is provided from the relationship between the internal pressure of the bellows tube and the refraction angles of the forceps. It was confirmed using this model that the developed system makes it possible to estimate both the strength and the direction of the external force applied to the forceps by measuring the internal pressure of the bellows tube. An operator using a three-dimensional haptic device was able to feel the force response during an experiment in which they used the forceps to hold a blood vessel. This report describes the most appropriate method for letting the operator feel the force conveyed by using our system. 展开更多
关键词 Hydraulic-driven FORCEPS force feedback surgical manipulator.
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Modeling and Analysis of Electrostatically Actuated MEMS under Combined Nonlinearities, Lorentz Force, and Mechanical Shock
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作者 Emran Khoshrouye Ghiasi 《Journal of Control Science and Engineering》 2016年第2期82-89,共8页
This paper shows an analysis ofMEM S (micro electro mechanical systems) due to Lorentz force and mechanical shock. The formulation is based on a modified couple stress theory, the von Karman geometric nonlinearity a... This paper shows an analysis ofMEM S (micro electro mechanical systems) due to Lorentz force and mechanical shock. The formulation is based on a modified couple stress theory, the von Karman geometric nonlinearity and Reynolds equation as well. The model contains a silicon microbeam, which is encircled by a stationary plate. The non-dimensional governing equations and associated boundary conditions are then solved iteratively through the Galerkin weighted method. The results show that pull-in voltage is dependent on the geometry nonlinearity. It is also demonstrated that by increasing voltage between the silicon microbeam and stationary plate, the pull-in instability happens. 展开更多
关键词 M EM S mechanical shock NONLINEARITY PULL-IN Galerkin weighted method dimensionless parameters.
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Practical Performance of High Bulk Modulus Oil
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作者 Toshiyuki Tsubouchi Jitsuo Shinoda 《Journal of Mechanics Engineering and Automation》 2012年第2期119-123,共5页
Although hydraulic drives have an advantage of high power density, volumetric shrinkage of hydraulic fluids due to pressure causes various disadvantages such as delay of hydraulic response and compression energy loss.... Although hydraulic drives have an advantage of high power density, volumetric shrinkage of hydraulic fluids due to pressure causes various disadvantages such as delay of hydraulic response and compression energy loss. Hydraulic fluids of new concept, high bulk modulus oils, have been developed as a new approach to improve the performance of a hydraulic servo system and verified. In this paper, practical performances of high bulk modulus oil, such as oil temperature rise during pump test, air bubbles generation by ultrasonic wave vibration, oxidation stability and anti-wear property, were studied. And the new oil was confirmed to have excellent practical performances besides advantages in pressure response and volumetric efficiency of pumps. Various new applications of the new oil are promising. 展开更多
关键词 Bulk modulus hydraulic fluid volumetric efficiency air bubble anti-wear.
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Electromechanical coupling driving control for single-shaft parallel hybrid powertrain 被引量:17
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作者 YANG Chao JIAO XiaoHong +3 位作者 LI Liang ZHANG YaHui ZHANG LiPeng SONG Jian 《Science China(Technological Sciences)》 SCIE EI CAS 2014年第3期541-549,共9页
The single-shaft parallel hybrid powertrain with the automatic mechanical transmission(AMT)is an efficient hybrid driving system in the hybrid electric bus(HEB),while the electromechanical coupling driving control bec... The single-shaft parallel hybrid powertrain with the automatic mechanical transmission(AMT)is an efficient hybrid driving system in the hybrid electric bus(HEB),while the electromechanical coupling driving control becomes a complicated question to find a transient optimal control method to distribute the power between the engine and the electric machine(EM).This paper proposes an innovative control method to deal with the complicated transient coupling driving process of the electromechanical coupling driving system,considering the accelerating condition and the cruising condition mostly in the city driving cycle of HEB.The EM might be operated at driving mode or generating mode to assist the diesel engine to work in its high-efficiency area.Therefore,the adaptive torque tracking controller has been brought forward to ensure that the EM implements the demand torque as well as compensate the torque fluctuation of diesel engine.The d?q axis mathematical model and back stepping method are employed to deduce the adaptive controller and its adaptive laws.Simulation results demonstrate that the proposed control scheme can make the output torque of two power sources respond rapidly to the demand torque from the powertrain in the given driving condition.The proposed method could be adopted in the real control of HEB to improve the efficiency of the hybrid driving system. 展开更多
关键词 single-shaft parallel hybrid powertrain coupling driving control adaptive control torque tracking
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Powertrain design and energy management of a novel coaxial series-parallel plug-in hybrid electric vehicle 被引量:7
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作者 ZHANG LiPeng QI BingNan +2 位作者 ZHANG RunSheng LIU JingChao WANG LiQiang 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2016年第4期618-630,共13页
For a series plug-in hybrid electric vehicle,higher working efficiency can be achieved by the drive system with two small motors in parallel than that with one big motor alone.However,the overly complex structure will... For a series plug-in hybrid electric vehicle,higher working efficiency can be achieved by the drive system with two small motors in parallel than that with one big motor alone.However,the overly complex structure will inevitably lead to a substantial increase in the development cost.To improve the system price-performance ratio,a new kind of series-parallel hybrid system evolved from the series plug-in hybrid system is designed.According to the technical parameters of the selected components,the system model is established,and the vehicle dynamic property and pure electric drive economy are evaluated.Based on the dynamic programming,the energy management strategy for the drive system under the city driving cycle is developed,and the superiority validation of the system is completed.For the studied vehicle driven by the designed series-parallel plug-in hybrid system,compared with the one driven by the described series plug-in hybrid system,the dynamic property is significantly improved because of the multi-power coupling,and the fuel consumption is reduced by 11.4%with 10 city driving cycles.In a word,with the flexible configuration of the designed hybrid system and the optimized control strategy of the energy management,the vehicle performance can be obviously improved. 展开更多
关键词 plug-in hybrid electric vehicle series-parallel hybrid system multi-power coupling dynamic programming energymanagement
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Coherent Destruction of Tunneling of Bosons with Effective Three-Body Interactions
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作者 牛真霞 鱼自发 薛具奎 《Communications in Theoretical Physics》 SCIE CAS CSCD 2015年第6期695-700,共6页
The tunneling dynamics of dilute boson gases with three-body interactions in a periodically driven double wells are investigated both theoretically and numerieally. In our findings, when the system is with only repuls... The tunneling dynamics of dilute boson gases with three-body interactions in a periodically driven double wells are investigated both theoretically and numerieally. In our findings, when the system is with only repulsive twobody interactions or only three-body interactions, the tunneling will be suppressed; while in the case of the coupling between two- and three-body interactions, the tunneling can be either suppressed or enhanced. Particularly, when attractive three-body interactions are twice large as repulsive two-body interactions, CDT occurs at isolated points of driving force, which is similar to the linear case. Considering different interaction, the system can experience different transformation from coherent tunneling to coherent destruction of tunneling (CDT). The quasi-energy of the system as the function of the periodicaJ1y driving force shows a triangular structure, which provides a deep insight into the tunneling dynamics of the system. 展开更多
关键词 Boson gases coherent destruction of tunneling three-body interactions
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