Performing permutations on interconnection networks by regularlychanging switch states

In this paper, we present an algorithm for performing permutations of messages on multistage interconnection networks. Permutations of messages are needed in many parallel algorithms. The proposed algorithm is feasible for any networks that can connect each input to each output using a set of N nonblocking connections, where N is the number of ports on the network. Messages are segmented into N submessages that are sent independently in each time step. For any permutation, the settings of switches are changed with fixed patterns. Partitioning of the network into independent subnetworks is also supported, each capable of simultaneously routing a different permutation     

Repeated Price Search

Consumers check few sites in online purchases. Previous research and experiments we perform demonstrate that consumers can not calculate the optimal strategy for price search. They use heuristics whose performance is better than random and less than optimal. To investigate online price search performance we survey student online textbook purchases. Students achieve good performance because they start with a good strategy and online market organization of marketplace and meta-search sites. An important factor is that algorithms at sites searched perform calculations that reduce the computational complexity of the search.     

湖泊湿地利用阶段演变的经济学分析——以太湖为例

人类对太湖湿地利用存在多种形式,但是在特定经济发展阶段的主导地位不同,存在太湖湿地利用阶段的演变,这个演变过程是在人类需求和湖泊湿地资源比较优势的共同作用下实现的,是实现丰富的自然资源对相对稀缺的自然资源的替代,是人造资本对自然资本和自然生产力进行替代的过程,是人类对太湖湿地依附性利用向和谐性利用转变的过程。     

Effect of dy on structure and magnetic properties of CoPt alloys

The effects of Dy on the microstructure and magnetic properties of Dy _x Co_50?x Pt₅₀ alloys were investigated. The XRD results indicate that all the alloys homogenized at 1000 °C contain only a single A1 (fcc) phase, while the alloys annealed at 675 °C consist of a hard-magnetic face-centered-tetragonal (fct) phase and a magnetically soft face-centered-cube (fcc) phase. Maximum values for the coercivity H _c and remanence ratio m _r were achieved in Dy_0.4Co_49.6Pt₅₀ alloys annealed at 675 °C for 80 min. For the series of Dy _x Co_50?x Pt₅₀ alloys annealed at 675 °C for 60 min, H _c decreases monotonically with increasing Dy concentration, but m _r is first enhanced and then weakened.     

Grigorii Valentinovich Samsonov

Obituaries

Grigorii Valentinovich Samsonov     

基于单片机的电脑弹簧机按键板的设计与实现

电脑弹簧机是用来生产弹簧的专用设备,按键板则是实现对弹簧机控制的一个人机交互的操作界面。本文介绍了电脑弹簧机按键板的设计及实现方法。该按键板采用薄膜面板开关的形式,用PS/2协议作为按键板和主机的通信手段,以单片机AT89S51作为处理芯片,设计灵活,使用方便可靠,具有锁键的功能,很好地满足了工业现场需求。它具有的通用性使得其能广泛应用于以PC机为主机的控制系统中。     

协同办公平台项目实施的解决方案

软件实施活动的目的是生产可执行的软件单，该文将软件工程的相关知识应用到项目实施中，提出了一套标准化的软件项目实施过程，实践性较强。     

空间信息处理技术与农田地理信息系统的研究

为了满足实施精细农业定位作物管理中数据管理与分析的需要,在对空间信息处理技术研究的基础上设计开发了一个农田地理信息系统。系统除了具有农田信息管理与数据处理的功能以外,还提供了处理GPS数据与RS图像的功能,方便了3S(GIS、GPS、RS)技术的集成应用。文章介绍了系统中GPS数据的制图与平滑处理、地图坐标转换、RS图像的几何校正与坐标配准、空间插值分析以及农田信息统计和查询等主要的功能及其实现方法。在北京精准农业示范区的应用表明系统可以作为一种用于精细农业研究的数据分析与信息管理的工具。     

面粉质量指标体系的聚类分析

引进聚类分析方法对面粉质量指标体系进行研究讨论。借助对一组测试数据的分析处理，介绍了用聚类分析方法研究面粉质量指标体系的详尽过程，并证实了这种方法的适用性。其中得到的重要结论为：与面粉烘焙品质极为相关的物理指标是３项“时间”指标，成份指标是“剩余蛋白含量     

开发连续平压机动向预测的研究

介绍了我国林业资源的现状和人造板工业产业政策的特点，对国内外人造板机械的发展趋势，节能与保护环境以及引进产品国产化的需要作了论述，对有关背影材料分析研究结果表明：因为符合“可持续发展”这个国民经济的总原则，我国开发连续平压机是可行的，还提出了开发连续平压机及生产线的基本思路。