DSC study on the motor protein myosin in fibre system

We have examined by DSC the complexes of myosin with actin in fibre system in the absence of nucleotides and the intermediate state of ATP hydrolysis by mimicking stable complex with myosin and ADP and beryllium fluoride in muscle fibres. Comparing the DSC results with other structural analogues of phosphate P_i leads the conclusion that the AM.ADP.BeF_x complex favours the AM.ADP.P_i complex in fibre system. The deconvolution of DSC scans resulted in four transitions, the first three transition temperatures were almost independent of the intermediate state of the muscle, the last transition temperature was shifted to higher temperature, depending on the actual intermediate states of ATP hydrolysis. In AM.ADP.V_i state the transition temperature at the second and third transitions (actin binding domain and myosin rod) varied only slightly, whereas the last one (the fourth transition) shifted markedly to higher temperature depending on the ternary complex, e.g. in case of ADP plus BeF_x it was 77.7 °C, the highest value in weakly binding state of myosin to actin. The sum of calorimetric enthalpies of the first and last curves was practically constant, but their fractions depended on the state of the muscle. In strongly binding state of myosin to actin (rigor, ADP state) the fraction of the first transition was much larger, than the last one, whereas in weakly binding state of myosin to actin, the fraction of the first transition decreased at the expense of the last one. It supports also the view that these transitions are parts of the same portion of the myosin molecule.     

摩托车起动齿轮精密冷锻模具设计

端面带棘齿的起动齿轮是摩托车行业通用的发动机起动机构零件 ,该件原由组合件经机加工后组合而成 ,工艺复杂。本文介绍了精密冷锻新工艺在该零件加工中的应用 ,重点介绍了模具结构及特点 ,为延长模具使用寿命 ,模具设计成组合结构 ,凸模采用过盈配合 ,不仅能够降低制造成本 ,而且提高了模具寿命 ,生产应用表明该模具平均使用寿命可达 1万件左右。     

隐极迭片转子同步电动机启动特性计算机仿真

本文提出了用多回路法来计算隐极迭片转子同步电动机的启动特性,包括各回路的电流;导出了用于似稳态和动态分析的数学模型;提出了用转子电阻分布系数来描述转子不对称性的方法.文中以一台22kW电动机为例,对不同阻尼绕组情况下的不同电阻分布系数γ进行了计算和分析,结果表明当γ接近零时,其启动特性接近于异步电动机的启动特性.实验还表明,计算结果与实验结果吻合较好.     

功率谱估计方法在SR电机转矩脉动控制中的应用

本文介绍了一种用功率谱估计来测量气隙磁通密度的方法，分析了该方法实现的理论可行性、具体的控制策略，并给出了原理框图和仿真结果。表明本方法能有效减小SR电机的转矩脉动，具有一定的应用价值。     

基于公路交通流量的中原城市群网络结构特征

研究了中原城市群各城市之间的高速公路流量、四级公路流量以及城际公交客流量，借助ArcMap的可视化空间分析工具，我们发现，中原城市群呈现出以郑州市为一级中心城市，新乡市、焦作市和许昌市为二级中心城市，洛阳市、开封市为三级中心城市的多中心枢纽网络空间发展格局。     

Matlab在《电机与拖动》教学中的应用

提出了利用Madab／Simulink设计电机与拖动实验的思想，介绍了Simulink的特点和仿真方法，并举例进行了说明。教学实践表明，《电机与拖动》课程中利用Madab仿真工具，不仅可以提高教学效果和教学质量，更能帮助学生对课程难点的深入理解和掌握。     

Worker deployment in dual resource constrained systems with a task-type factor

This paper investigates worker learning and forgetting phenomenon in a dual resource constrained system (DRC) setting. Worker learning and forgetting in two and three stage DRC systems are modeled according to the dual-phase learning and forgetting model (DPLFM), which is based on the theory that a task has separate cognitive and motor requirements. Results show that the task-type (with respect to its learning rate and proportion of cognitive and motor requirements) affects the performance of training and deployment policies in DRC systems, and as such it should be included in future DRC research.     

Network hub location problems: The state of the art

Hubs are special facilities that serve as switching, transshipment and sorting points in many-to-many distribution systems. The hub location problem is concerned with locating hub facilities and allocating demand nodes to hubs in order to route the traffic between origin–destination pairs. In this paper we classify and survey network hub location models. We also include some recent trends on hub location and provide a synthesis of the literature.     

运动技能学习的理论模型综述

从认知心理学角度综述了国外学者关于运动技能学习的理论模型方面的研究进展，旨在揭示运动学习获得和发展的内在规律，以提高体育教学和训练效果提供理论依据和实践指导．