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41.
The method and principle of the parameter design for the power train of EV is explored and discussed,then the parametersof EV. based on SC7101 are reasonably selected.The method of calculating the SOC of Lead_acid battery is provided and the relation among the electromotive force,the interior resistance, the polarized resistance and the SOC are analyzed. The capacity is compensated according to the relation between the capacity and the temperature, which is the basis on which the energy management system is designed and improved. The dynamic model which reflects the dynamic characteristics of the power train is established,then the dynamic performance of the EV based on SC7101 is simulated, and the factors that affect the continuous mileage of EV are analyzed,the measures to increase the continuous mileage are provided.The result shows that the analysis of the electric characteristics of battery and the dynamic model are correct,and the dynamic performance perfectly meets the need of the design target. 相似文献
42.
It is important for enterprises' inventory management to find out the optimal production cycle and the length of shortage time,so that the total cost of inventory system can be reduced and the service level can be raised.Based on the classical EPQ model,this paper develops an EPQ model for deterioration items with different lost sale factor relative to the inventory level during shortage period.The existence of unique optimal solution is discussed by mathematic analysis and a numeric example.The sensitivity analysis shows that the parameter of losing sale has different impact on the costs of inventory system.The factors must be considered for the production inventory system to make management decision. 相似文献
43.
In the course of searching immunodulators from natural herbal sources,the polysaccharide has been isolated from the water extract of duckweed(Herba Spirodelae seu Lemnae).The authors aim at investigating the methods that determine the content of total saccharides in the mixture,accordingly,to be used as a quality control in the procedure of producing polysaccharides from duckweed.The contents of saccharides in the extraction were mensurated by spertrophotometry of sulphuric acid-phenol and sulphuric acid-anthrone.And the validitiy of methods was evaluated through some indexes such as linearity and range,precision,stability,and accuracy.The results reveal the methods are convenient,rapid,accurate,and high sensitive,thereby leading to a wide and effective use in determining the saccharides contents in polysaccharides extraction from Herba Spirodelae seu Lemnae. 相似文献
44.
The author introduces a method and experimental procedures that determine dn/dc,molecular weight and its distribution of the hyroxyethyl starch(HES) by means of Gel Permeation Chromatography-Refractive index-Multi-angle laser light scattering detection(GPC-RI-MALLS)techniques.The key experimental technique and results are discussed.The method takes CH3COOH/CH3COONa as mobile phase and solvent.The experiment gets satisfactory results.It can be used as a routine method to determine the hyroxyethyl starch(HES) molecular weight and its distribution. 相似文献
45.
In this paper,the axisymmetrical shells of suspension crosssection is studied by means of integral equation in initial parameter form.An example of the shells under uniformly distributed load is calculated. 相似文献
46.
Zhang Jisheng He Kangyu 《保鲜与加工》1992,(6):25-30
A new mechanical model on impact system with non-linear element is presented and the practical method for measuring and identifying the parameters is also studied. The results of the experimental analysis and theoretical calculations are satistactory. And we hope to provide more acurate theorecical model for the study and design of impact dampers. 相似文献
47.
He Enqi Liu Xirong 《保鲜与加工》1988,(2)
In this paper,we have studied the change law of the structural parameter of coal in Nan Tong Coal Mine with the increasing the temperature. At the same time, we explore the cause of the changes with the electron microscope and of infrared spectrum. 相似文献
48.
主要利用计算机CAD/CAE/CAM技术,针对钢圈产品的结构特点,使用Solid Edge软件建立钢圈的三维模型。并基于Solid Edge数据库开发技术利用vb语言对钢圈产品进行参数化设计,开发了相应的参数化设计软件。重点介绍了钢圈产品参数化设计过程、系统功能及其实现。通过参数化软件的建立,提高产品的可定制性和设计速度,减少大量的重复的绘图工作,为钢圈的结构优化提供了有利的工具。 相似文献
49.
概述了配气机构凸轮型线的设计方法。根据配气机构振动特征数ε确定了两种型线函数(组合式和高次方式),对4108型高速柴油机凸轮型线进行了设计计算,并对配气机构进行了动力特性计算。在相同的初始条件下,比较了两种型线的各种性能参数的差别,对两种凸轮型线的优劣作出了评判。 相似文献
50.
BY-150型种子包衣机检测控制系统设计 总被引:1,自引:0,他引:1
包衣机在批量加工流程中需要针对供种量和进液量等重要参数进行检测,否则无法保证良好的包衣效果。为此,设计了一种包衣机检测控制系统,可实现对供种量和进液量参数信息的检测和控制。同时,需在供种量检测模块的硬件选型和电路设计中采用尽可能多的抗干扰措施保证种子质量的检测精度,在进液量检测模块的设计中通过采用主板信号控制动作启动、传感器检测电路直接控制动作结束的方式保证进液控制的稳定性,并通过液晶触摸屏为用户提供一个简单直观的人机交互方式。整个系统稳定可靠、抗干扰性好,满足预期的精度要求,包衣效果良好。 相似文献