A Spot Price Model with Var Cost     

Chang Baobo Sun Hongbo 《保鲜与加工》1997,(6):16-22

This paper has applied the var cost to the theory of spot price.An augmented Lagrange method is employed to develop the exact model of spot price of active power and reactive power,and the physical means of Lagrange multipliers are explained.The numerical examples are given to demonstrate the validity of the proposed model.  相似文献   

Loads Equalization Based on Optimization Principle and the Hierarchical Model for Distribution Networks     

LIN Jing dong  CAO Chang xiu  ZHANG Bang li 《保鲜与加工》2002,(5):29-32

Loss reduction is important for distribution networks and it is available to reduce loss by loads equalization. With increasing numbers of vertexes in distribution networks, compounding of loads are rapid increasing. It is hard to achieve the global optimization for load balancing by traditional model of distribution networks. Base on analyzing character of loads equalization for distribution networks, this paper provides a new method which conjugate the optimization principle and the hierarchical model of the distribution networks, can transfer the optimization issues into multi stage decision making problems,and can also achieve the optimization equalization of the distribution networks loads.  相似文献   

Summarization of Current Research on Application of Durability of Structures     

LI Hong yi  CHEN Zhao hui  BAI Shao liang  XIANG Chang kui 《保鲜与加工》2001,(2):98-103

This paper summarized the recent research results about the durability of structures, introduced their current application in durability design, appraisal, estimation of rest life and strategy of maintenance and strengthening as well as in other fields.  相似文献   

Seismic Behavior of Asymmetric Building under Pushover Analysis     

LIU Chang  ZOU Yin-sheng 《保鲜与加工》2007,(3):61-65

Pushover analysis is a tool to study the inelastic behavior of structures under strong seismic action. The 3D-pushover analysis was performed to analyze the inelastic lateral-torsional coupled response of multistory asymmetric structures. The symmetric frame and frame-wall systems were studied in this paper, and the capability curve of the top displacement and base shear,the story drift and the position of rotation center were compared with reference to corresponding symmetric structures. The characters of inelastic response of multistory asymmetric structures were found. The conclusion provides reference for performance-based seismic design of asymmetric structures.  相似文献   

基于角位移控制的功率分流式自动变速器速比控制研究     

魏英俊  常思勤 《拖拉机与农用运输车》2005,(5):52-53

阐述了功率分流式自动变速器中电机控制式无级变速单元的速比控制原理。通过对速比控制电机目标角位移、角位移滑模变结构控制器的建模,来确定整个控制器的设计参数。在对角位移目标轨迹跟踪的仿真中,控制器能够较好地实现在有外在负载干扰下对角位移目标轨迹的跟踪。  相似文献   

装载机发动机与液力变矩器功率匹配优化   总被引：7，自引：0，他引：7  

常绿  王国强  唐新星  李春然  杨涛 《农业机械学报》2006,37(11):28-31

装载机发动机与液力变矩器之间的匹配对各自性能的发挥及整机牵引特性均有重要的影响。在拟合装载机发动机与液力变矩器有关特性曲线的基础上,以装载机的动力性为目标,建立发动机与液力变矩器匹配的优化模型,优化装载机发动机与液力变矩器的功率匹配,给出了算例并分析了优化结果。  相似文献   

神经网络方法在车内噪声信号预测中的应用   总被引：3，自引：1，他引：3  

常振臣  王登峰  周淑辉  卢延辉 《农业机械学报》2003,34(1):21-24

针对以往车内噪声有源控制过程中存在的次级声源在初级声场采样传声器上的声反馈问题，提出了车内噪声信号识别和预测的神经网络方法。对被试面包车在稳态和非稳态两种工况下的试验研究表明，利用车身悬置点和发动机的振动信号，通过BP神经网络来识别和预测车内驾驶员耳旁噪声是可行的，可以解决次级声源在初级声场采样传声器上的声反馈问题。  相似文献   

铰链密封式传动滚子链的道路试验研究     

金昌  孟繁忠  黄梅 《农业机械学报》2003,34(3):112-114

通过30000km道路行驶试验研究表明，密封滚子链的磨损形式，对销轴和套筒而言是以疲劳磨损为主,伴随有粘着磨损与磨粒磨损；对链板和O形圈而言主要是疲劳磨损，并且O形圈的磨损要比链板的磨损严重得多。销轴和套筒表层磨损后产生了循环硬化特性，有利于提高其铰链副的耐磨性。  相似文献   

棉田膜内与膜间土壤溶液含盐量的变化   总被引：1，自引：0，他引：1  

黄强  田长彦  赵正勇  汪宏年  张建军  陈春英 《灌溉排水学报》2001,20(3):37-40

用定期取表层土样测定其电导率和在不同深度埋设盐分传感器探头的方法 ,在作物生长季节内 ,监测了棉田膜内和膜间不同深度的土壤溶液含盐量变化。结果为 :1棉田膜内与膜间表层土壤和 1 0 cm、30 cm深土壤溶液含盐量变化较大 ,且规律相同。未灌水时上升 ,灌水后迅速下降。膜间未灌水期间的含盐量上升幅度大于膜内 ,灌水对膜内和膜间表土洗盐、1 0 cm、30 cm深土壤溶液含盐量的降低作用没有差别。降雨可引起膜内和膜间 1 0 cm深土壤溶液电导率的变化 ,这个影响也是膜间大于膜内。 2 60 cm深的土壤溶液不存在明显的盐分累积现象 ,灌水可使这里的土壤溶液含盐量缓慢降低 ,膜间的降低过程快于膜内  相似文献   

江苏省水稻节水灌溉技术推广模式     

俞双恩  张展羽  陶长生  王菊 《灌溉排水学报》2001,20(3):33-36,40

针对江苏省稻作区水资源、土壤、气候的特点 ,选择浅湿灌溉、浅湿调控灌溉、控制灌溉、水稻旱作灌溉等 4种技术因地制宜进行推广。在灌溉过程中 ,建立和完善了一整套的组织措施和技术措施 ,形成了江苏省水稻节水灌溉技术推广模式 ,取得了显著的效果 ,丰富了水稻节水灌溉技术推广的内容  相似文献