Optimal resource allocation for transmission diversity in multi-radio access networks： a coevolutionary genetic algorithm approach

The next generation wireless communication systems aim at supporting enhanced diversified network access and data transmission abilities via the cooperative integration and unified management of various radio access technologies(RATs).The resource allocation is the core component leading the network system and mobile terminals to the service robustness and performance maximization.In this paper,a numeric optimization model for optimizing terminals’transmission power and allocated RAT bandwidth for maximizing system capacity is proposed with the focal consideration of the multi-radio transmission diversity for parallel transmission through multiple links from diferent RATs,and diferent terminal characteristics on RAT supports.Also,we design a centralized and periodic scheduling algorithm including an improved coevolutionary genetic algorithm for efciently solving the optimization problem.Simulation results demonstrate that our propose algorithm can distinctly enhance the system performance and improve the computational efciency.     

Guaranteed transient performance based control with input saturation for near space vehicles

This paper describes the design of guaranteed transient performance based attitude control for the near space vehicle(NSV)with control input saturation using the backstepping method.To improve the robust controllability of the NSV,the parameter adaptive method is used to tackle the integrated effect of unknown time-varying disturbance and control input saturation.Based on the backstepping technique and parameter estimated outputs,a robust attitude control scheme is proposed for the NSV with input saturation.A novel robust attitude control scheme is then proposed based on a prescribed performance bound(PPB)which characterizes the convergence rate and maximum overshoot of the attitude tracking error.The closed-loop system stability under both the developed robust attitude control schemes is proved using Lyapunov’s method and uniformly asymptotical convergence of all closed-loop signals is guaranteed.Finally,simulation results are given to show the effectiveness of both the proposed robust constrained attitude control schemes.     

基于SITRANS料位计的监控系统设计

针对吕梁山木瓜煤矿原有料位计老化、测量不准确等问题,设计基于SITRANS LU 10超声波料位计的自动监控系统。系统采用S7-300系列PLC及组态软件作为控制核心,通过WinCC组态管理软件可直观地显示料位数据实时变化,实现煤仓料位的自动检测、超限报警、卸料小车运行与卸料控制等功能。     

干熄焦提升机控制系统的优化

从控制时序、系统拓扑结构、传动部分等方面介绍干熄焦提升控制系统。通过一起焦罐坠落事故,分析干熄焦提升控制系统存在的问题,并提出解决方案。     

阳离子交换树脂催化合成十三碳二元酸二乙酯

以强酸性阳离子交换树脂为催化剂,十三碳二元酸与乙醇为原料合成十三碳二元酸二乙酯,考察了影响反应的因素。结果表明:醇酸摩尔比为4∶1,催化剂用量为酸质量的2%,在3分子筛脱水的情况下反应7 h,酯化率达98.4%,并且催化剂可重复使用3次。     

稀土固体超强酸催化合成乙酸异戊酯的研究

制备出一系列稀土固体超强酸催化剂 ,用于催化以乙酸和异戊醇为原料合成乙酸异戊酯的反应。研究了稀土固体超强酸的催化性能 ,同时 ,考察了影响合成反应的因素。结果表明 ,稀土固体超强酸不仅具有一般超强酸的性能 ,而且催化活性更高 ,性能更稳定。     

气固错流移动颗粒床过滤器压降特性研究

研究了错流移动颗粒床过滤器操作压降与过滤介质特性、表现过滤气速、颗粒层移动速度和床层粉尘沉积量之间的关系。结果表明，无粉尘沉积时，床层压降可以用Ergun方程计算。颗粒层移动速度的变化并不会造成床层压降的显著变化。除尘过程中，床层内粉尘沉积量随气体中粉尘浓度的增大、颗粒层移动速度的减小而增加，同时将导致床层压降的显著增大。错流移动床除尘操作压降可以用带修正项的Ergun方程计算，其修正项为比沉积率和颗粒层空欧率的函数。在实验数据范围内，该方程的计算结果与实验数据最大偏差小于15％。     

影响磷酸浓缩工序运行的因素及对策

我公司 12 0ｋｔ/ａ(Ｐ2 Ｏ5计 )磷酸装置是 2 0世纪80年代末引进法国Ｒ -Ｐ二水物工艺建设的 ,其中的浓缩工序将ω(Ｐ2 Ｏ5)为 2 8%的磷酸通过强制循环真空浓缩到ω(Ｐ2 Ｏ5)为 5 0 %的浓磷酸 ,并副产ω(Ｈ2 ＳｉＦ6)为 2 3%的氟硅酸。本文主要介绍该装置浓缩工序的运行状况 ,     

气辅注射成型及设计要点

概述了气辅注射成型过程中材料的选择、气道及模具的设计     

论高校网络视频在思想政治教育中的作用

校园网络视频是高校开展思想政治工作的重要阵地,也是一种新型有效传播社会主义先进文化的重要载体,它具有发挥宣传和舆论导向、教书育人、素质教育等独特作用.