The Properties of Sulfur Rubber Concrete （SRC）

The mix designs and specimen preparation for the dry process and wet process of sulfur rubber conerete （ SRC ） were investigated. The compressive strength, corrosion-resistance and toughness were studied and discussed. The results show that SRC is corrosion-resistanet. Although the compressive strength of SRC decreases with inereasing rubber content, the toughness increases instead . Adding micro-filler will improve the compressive strength of SRC . There is a threshold value for the sulfur content, at which the compressive strength and the workability of SRC reach an optimum balance . The bond between rubber particles and surrounding sulfur is strong due to the vulcanization process that generates cross-link through S-C bonds.     

综合负荷动静比例对电网传输功率的影响分析

电力系统仿真计算中,综合负荷的动态和静态成分所占比例对电网的暂态极限有着重要的影响。文章根据湖南电网的实际特点和电网结构以及运行情况,研究了综合负荷模型中不同感应电动机比例对湖南电网南北断面南送功率传输极限的影响,分析了综合负荷模型与恒阻抗加恒功率的静态负荷模型应用于湖南电网对断面南送功率极限的不同影响,并在此基础上分析了综合负荷模型和参数变化对电力系统稳定水平影响的机理,最后对湖南电网负荷模型和参数的选取提出了建议。     

模糊控制在空调清洗系统中的应用

描述了烘干罐温度模糊控制器的设计原理及控制系统的软硬件组成,由AT89C52实现的空调烘干控制系统,实现了空调清洗烘干自动化.实际运行表明,烘干系统具有控制精度高、动态响应好、可靠性高、抗干扰能力和鲁棒性强等特点.     

材料浓缩技术温度测控方法的研究

针对机械式蒸汽再压缩浓缩技术对二次蒸汽温度不能进行实时监控,产生能源浪费的问题,采用西门子S7 200PLC控制器为核心元件搭建一套实时监控系统对二次蒸汽温度进行监控.该系统在计算机软件驱动下,运用比例积分微分指令模块构建闭环反馈调节系统对二次蒸汽温度进行调控,并用仿真软件对闭环反馈调节系统进行模拟.针对压缩机能耗问题,在电动机上串联变频器,通过可编程逻辑控制器控制变频器,改变电动机的转速降低能耗。研究表明,闭环反馈调节系统能够实现对二次蒸汽温度的实时控制,且人机界面可以直接监控系统的运转状况,并通过变频器改变电动机的工作频率可以降低能耗.该系统组建简单方便,适合对机械式蒸汽再压缩浓缩系统进行实时监控.     

以拔头油(液态轻烃)为原料生产城市管道煤气的技术及其应用

本文介绍了以低成本的拔头油(液态轻烃)替代液化石油气作为原料生产城市人工煤气的原理、技术方案及实施效果,分析了该项技术的市场应用前景,为科学利用炼油厂重整拔头油找到了一条理想的途径,对煤气生产企业降低成本、提高效益有一定帮助。     

Radial Clearance Control and Internal Leakage Analysis of a Tri-Proportion Controller

The tri-propellant thermal propulsion system is one of the hottest subjects in the field of underwater vehicles recently.To improve efficiency of underwater vehicles,a method of radial clearance control of the tri-proportion has been proposed.Based on analyzing the factors which influence the pressure decrease and leakage of the tri-proportion controller,a method is used for precision analysis and proportion adjustment by using the median optimizing theory.Analysis results show that accuracy of the proporti...     

大型装置起竖过程的电液比例控制研究

以机动导弹发射架为例,研究了大型液压驱动机械装置起竖过程的控制问题,分析了起竖过程中液压缸的载荷情况,给出了进入多级缸油液的压力、流量与起竖角度间的关系曲线,提出了基于电液比例技术的起竖过程控制方案,实现了对液压油源和起竖速度的灵活控制,仿真结果表明该方案可以用于快速起竖系统设计。     

卡拉胶与魔芋粉复配生产果冻粉的研究

文章对卡拉胶及魔芋粉复配生产果冻粉进行研究,在不同的配制比例,不同的pH环境,不同的酸化浓度,不同温度下加酸和不同的KCl浓度下形成凝胶。从果冻凝胶强度、粘弹性、持水性、透明性、口感方面确定卡拉胶、魔芋粉及KCl三种配料在果冻中的最佳配方,并对所得结果进行初步的解释、探讨和推测。     

A column‐generation‐based approach to fleet design problems mixing owned and hired vehicles

We look at the problem of choosing a fleet of vehicles to carry out delivery tasks across a long time horizon. The delivery quantities may vary significantly from day to day, and from season to season, and the underlying routing problem may have rich constraints, for example, time windows, multiple compartments, multiple commodities, and compatibility constraints. We consider the option of hiring extra vehicles from external carriers in order to efficiently carry out the day‐to‐day operations while containing the costs of owning the fleet. The goal is to design a fleet so as to minimize the sum of costs of routing the fleet every day of the horizon, the acquisition costs, the maintenance costs, and the costs of hiring external vehicles. In the literature, there is no previous work on fleet design for a long time horizon, which also considers the hiring options. We propose to tackle the problem using column generation and develop three different heuristics. The methods proposed are tested and compared on a set of real‐world problems. It is also shown how introducing the possibility of hiring helps reducing the overall cost and the number of idle vehicles over the planning horizon.     

功能性酸乳中每种益生菌的单独计数方法及其混合发酵工艺的研究

通过研究分析功能性酸乳中双歧杆菌和各种乳酸菌在BBL平板培养基上的菌落特征及菌体形态,提出了一种可同时准确对每种益生菌单独计数的新方法,从而可直观地观察到各种益生菌的生长活度,免除了传统方法计数不同有益菌数要用不同培养基的繁琐,为生产和检测提供了依据;还对功能性酸乳的混合发酵生产工艺进行了研究,确定了最佳的菌种比例,按嗜热链球菌3%、保加利亚乳杆菌2%、嗜酸乳杆菌4%、双歧杆菌10%接种,39℃发酵11~13h,酸乳产品既保持了普通酸乳的良好口感和风味,又保证了双歧杆菌和乳酸菌活菌数在贮存期内均大于108cfu/mL,增强了酸乳的保健功能。