磁敏测速系统的数据采集平台实现

串口同步采集是工业控制应用的重要环节,为克服由于不准确的数据采集所带来的乘性误差,进而对多串口的同步采集进行了研究。利用VS2005编程环境,设计实现了多串口的上位机数据采集平台,该平台开辟线程对多个串口采取重叠读取方式,实现了对测速系统中大量的串口数据同步读取、保存并实现波形动态显示的功能,满足了智能测速系统的测速算法研究的需要。此平台可以广泛的应用在测速系统之中,也可辅助用于各种工业控制的高级要求。     

罗汉果体积的数字图像测量方法

为了提高检测效率,实现罗汉果体积自动精确测量,采用摄像机获取罗汉果个体俯视图和不同角度的4幅侧视图.通过二值化后的罗汉果俯视图计算罗汉果的圆度误差,再利用侧视图,采用有限元的方法计算罗汉果体积,并对体积进行修正.将图像测量结果与采用物理方法所测结果进行比较,结果证明此测量方法是有效可行的.这项技术可用于罗汉果及类似的农...     

Internetware: An Emerging Software Paradigm for Internet Computing

The Internet is undergoing a tremendous change towards the globalized computing environment.Due to the open,dynamic and uncontrollable natures of the Internet,software running in the Internet computing environment has some new features,which bring challenges to current software technologies in terms of software model,software operating platform,software engineering approaches and software quality.Researchers in China have proposed the term "Internetware" to present the emerging software paradigm.Sponsored by the National Basic Research 973 Program,several research practices have been done on the Internetware in the past decade.This paper summarizes the progress and status of the Internetware researches.A technical solution framework for the Internetware paradigm is proposed from four aspects:the Internetware software model defines what the Internetware is to be;the Internetware middleware determines how to run the Internetware applications;the engineering methodology determines how to develop the Internetware applications;the Internetware quality assurance determines how well the Internetware applications can perform.The paper also discusses the ongoing research issues and future trends of Internetware.     

A 1-Local Asymptotic 13/9-Competitive Algorithm for Multicoloring Hexagonal Graphs

In the frequency allocation problem, we are given a mobile telephone network, whose geographical coverage area is divided into cells, wherein phone calls are serviced by assigning frequencies to them so that no two calls emanating from the same or neighboring cells are assigned the same frequency. The problem is to use the frequencies efficiently, i.e., minimize the span of frequencies used. The frequency allocation problem can be regarded as a multicoloring problem on a weighted hexagonal graph. In this paper, we give a 1-local asymptotic 4/3-competitive distributed algorithm for multicoloring a triangle-free hexagonal graph, which is a special case of hexagonal graph. Based on this result, we then propose a 1-local asymptotic13/9-competitive algorithm for multicoloring the (general-case) hexagonal graph, thereby improving the previous 1-local 3/2-competitive algorithm. A preliminary version of this paper appeared in the Proceedings of the 13th Annual International Computing and Combinatorics Conference (COCOON 2007), LNCS 4598, pp. 526–536. Y. Zhang research was supported by European Regional Development Fund (ERDF). F.Y.L. Chin research was supported by Hong Kong RGC Grant HKU-7113/07E. H. Zhu research was supported by National Natural Science Fund (grant #60496321).     

STBC系统在非同分布Nakagami信道下的一种快速性能评估算法

针对非同分布的Nakagami信道,基于矩生成函数MGF(Moment Generation Function)的分析方法,提出正交空时分组码系统STBC(Space-Time Block Coding)的一种快速性能评估算法,不需要涉及超几何函数积分运算,可在中高信噪比时,快速准确地估计STBC系统的符号错误概率性能。在平坦瑞利衰落信道下的计算机仿真表明,该算法与已有的STBC系统的近似估计算法相比,具有较优的性能。     

A two-machine flowshop problem with processing time-dependent buffer constraints—An application in multimedia presentations

To have a quality multimedia presentation through networks, its presentation lag needs to be controlled. One way to reduce the lag is to prefetch the media objects before their due dates. This paper explores techniques for optimizing the object sequence in a prefetch-enabled TV-like presentation. An optimal solution is the one with which the presentation lag is minimized. We formulate the problem into a two-machine flowshop scheduling problem with a single chain precedence constraint and a player-side buffer constraint. The player-side buffer is “processing time-dependent” and distinguished from the conventional item-based intermediate buffer constraints discussed in previous flowshop studies. We prove the problem to be strongly NP-hard. A branch and bound algorithm equipped with four lower bounds and an NEH-based upper bound is developed. The simulation results show that the average gaps between the overall lower bounds and the NEH-based upper bound are less than 3% for problems with a large buffer size, and less than 13% for problems with a small buffer size and high density of precedence constraints. For applications where the media objects are delivered through extremely busy servers with which only very restricted CPU resources can be allocated for computation, the CDS-based algorithm provides better sequences than the NEH-based algorithm.     

On some new approximate factorization methods for block tridiagonal matrices suitable for vector and parallel processors

In this paper, to obtain an efficient parallel algorithm to solve sparse block-tridiagonal linear systems, stair matrices are used to construct some parallel polynomial approximate inverse preconditioners. These preconditioners are suitable when the desired goal is to maximize parallelism. Moreover, some theoretical results concerning these preconditioners are presented and how to construct preconditioners effectively for any nonsingular block tridiagonal H-matrices is also described. In addition, the validity of these preconditioners is illustrated with some numerical experiments arising from the second order elliptic partial differential equations and oil reservoir simulations.     

DCS系统常见故障排除经验

结合生产控制系统实际,提出处理DCS系统故障前应做的准备,介绍系统硬件故障判别方法,重点阐述DCS常见故障的经验查找和处理.     

中试装置JX-300XP DCS控制系统的调试

介绍中试装置JX-300XP DCS系统的建设和配置组成,并详细说明了调试的方法和步骤.