基于最小均方插值的码元同步算法研究

从软—硬件协同设计的角度出发 ,提出了软件无线电系统中码元同步的一种实现方案。该方案以信号插值为理论基础 ,用软件实现整个码元同步过程。其特点是以估计性能更佳的最小均方滤波器替代传统的多项式插值滤波器 ,并利用软件实现时可以进行大批量数据缓存的优势 ,提出能量检测算法 ,以克服半码元周期传输延迟时出现的高误码率问题     

危险的致癌物质——亚硝胺

环境中的有毒的致癌物质越来越多 ,亚硝胺就是其中一种。虽然它在环境中含量并不大 ,但由于它来源的广泛性和致癌机理的特殊性 ,已引起了人们的高度重视。本文对亚硝胺的来源、形成条件、致癌机理及控制方法作了探索性研究     

标记VLAN技术及其应用

介绍标记VLAN的技术及其应用于局域网和武警学院校园网中的解决方案.     

近红外光谱技术快速测定汽油中芳烃、稀烃含量

对近红外光谱法预测汽油中的稀烃、芳烃含量进行了研究,用全交互验证法对36个不同油库、加油站汽油样品中的稀烃、芳烃含量进行了预测。研究结果表明,近红外光谱法预测汽油中的稀烃、芳烃含量方法可靠,预测结果能够满足国家标准对稀烃、芳烃含量分析的误差要求。     

Optimal policies for M/M/m queue with two different kinds of (N,T)‐policies

In this paper, two different kinds of (N, T)‐policies for an M/M/m queueing system are studied. The system operates only intermittently and is shut down when no customers are present any more. A fixed setup cost of K > 0 is incurred each time the system is reopened. Also, a holding cost of h > 0 per unit time is incurred for each customer present. The two (N, T)‐policies studied for this queueing system with cost structures are as follows: (1) The system is reactivated as soon as N customers are present or the waiting time of the leading customer reaches a predefined time T, and (2) the system is reactivated as soon as N customers are present or the time units after the end of the last busy period reaches a predefined time T. The equations satisfied by the optimal policy (N*, T*) for minimizing the long‐run average cost per unit time in both cases are obtained. Particularly, we obtain the explicit optimal joint policy (N*, T*) and optimal objective value for the case of a single server, the explicit optimal policy N* and optimal objective value for the case of multiple servers when only predefined customers number N is measured, and the explicit optimal policy T* and optimal objective value for the case of multiple servers when only predefined time units T is measured, respectively. These results partly extend (1) the classic N or T policy to a more practical (N, T)‐policy and (2) the conclusions obtained for single server system to a system consisting of m (m ≥ 1) servers. © 2000 John Wiley & Sons, Inc. Naval Research Logistics 47: 240–258, 2000     

基于PC机对多总线导航计算机软件开发方法的研究

对基于多总线结构的计算机传统软件开发方式的局限性进行了分析 ,对一种基于IBM PC机为开发平台 ,采用 C语言开发的软件开发方法进行了研究和探讨 .文章对这一方法在使用中所存在的主要问题和解决的主要技术手段作了介绍 .在实际开发过程中 ,该方法已被证明简便、可行、有效 ,这对于类似基于多总线结构的导航计算机的许多计算机的软件开发均有一定的借鉴作用     

化学危险品运输车辆应防火灾爆炸事故

本文通过具体案例分析了化学危险品运输车辆可能发生火灾爆炸事故的原因,并提出了应采取的安全措施。     

Scheduling to minimize the total compression and late costs

We consider a single-machine scheduling model in which the job processing times are controllable variables with linear costs. The objective is to minimize the sum of the cost incurred in compressing job processing times and the cost associated with the number of late jobs. The problem is shown to be NP-hard even when the due dates of all jobs are identical. We present a dynamic programming solution algorithm and a fully polynomial approximation scheme for the problem. Several efficient heuristics are proposed for solving the problem. Computational experiments demonstrate that the heuristics are capable of producing near-optimal solutions quickly. © 1998 John Wiley & Sons, Inc. Naval Research Logistics 45: 67–82, 1998     

大型柔性空间结构的多级分散化振动控制

文中直接以结构的动力学变量作为系统状态,从理论上推导出了反馈和状态变量的解析表达式。基于该表达式,对一空间站模型进行了仿真。结果表明,该方法具有计算量小、稳定性好的优点,便于在线控制。     

扭轮摩擦驱动系统研究

扭轮摩擦驱动是集摩擦传动和螺旋传动为一体的传动系统,它既具有摩擦传动动态特性好,同时又有螺旋传动导程小的特点。本文介绍一种扭轮摩擦驱动系统,它的导程小于０．２ｍｍ,行程为２５０ｍｍ,运动分辨率可达纳米级水平。它由扭轮摩擦传动机构、气体静压导轨及相关部件组成,是一种大行程高分辨率的新型驱动系统。