Recombinant Landscapes in the American City

How are urban actors, such as landscape designers, community groups, developers and local politicians, actively restructuring their environments to meet the challenges of the American city in the new global context? Grahame Shane outlines the approaches to landscape that have been emerging since the mid-20th century and are set to recombine urban assemblages whether they are located in historic city centres, postindustrial waterfronts or suburban sprawl. Copyright © 2007 John Wiley & Sons, Ltd.     

Experimental analysis of a mass storage system

Mass storage systems (MSSs) play a key role in data‐intensive parallel computing. Most contemporary MSSs are implemented as redundant arrays of independent/inexpensive disks (RAID) in which commodity disks are tied together with proprietary controller hardware. The performance of such systems can be difficult to predict because most internal details of the controller behavior are not public. We present a systematic method for empirically evaluating MSS performance by obtaining measurements on a series of RAID configurations of increasing size and complexity. We apply this methodology to a large MSS at Ohio Supercomputer Center that has 16 input/output processors, each connected to four 8 + 1 RAID5 units and provides 128 TB of storage (of which 116.8 TB are usable when formatted). Our methodology permits storage‐system designers to evaluate empirically the performance of their systems with considerable confidence. Although we have carried out our experiments in the context of a specific system, our methodology is applicable to all large MSSs. The measurements obtained using our methods permit application programmers to be aware of the limits to the performance of their codes. Copyright © 2006 John Wiley & Sons, Ltd.     

两种数据存储格式之间的互相转换

石油地震采集的数据一般均采用SEGY（Society of Exploration Geophysicists Y）格式中的IBM32（International Business Machines）格式存储,商业化石油地震数据处理软件可以直接读取。而在PC机上开发特殊处理模块时,通常要读的数据文件要求是按IEEE（Institute for Electrical and Electronic Engineers）格式存储方式的数据。如果不进行数据格式转换,读取的数据会面目全非。为了适应两种地震数据处理软件之间的数据通讯,必须弄清楚两种数据存储方式的特征,并编制相应的互相转换程序。本文提供了两种数据存储方式之间互相转换的源程序。     

基于IBM Cell多核平台的OpenMP数组私有化技术研究

数组私有化是并行化编译中的重要技术之一,IBM Cell是异构多核处理器,SPMD代表实现OpenMP数组私有化的重要手段,但是SPMD形式的OpenMP程序却不能直接通过IBM XLC(适用于IBM Cell多核平台的编译器)的编译.为了解决该问题,并充分利用IBM Cell本地存储器中的静态缓冲区以减少DMA通信,提出一种IBM Cell多核平台的OpenMP数组私有化技术.旨在充分利用本地存储器、减少DMA通信,集中处理可重用数据的私有化.主要包括:数组私有化分析、数组私有化转换、同步消除与非阻塞DMA操作,从而扩大数据的可重用作用域.转换后的Jacobi迭代代码进行实际测试表明,这种基于IBM Cell多核平台的数组私有化技术能够平均提高3%左右的执行性能,尤其对于小规模计算来说性能提高还会更多.     

面向统计机器翻译的重对齐方法研究

词对齐是统计机器翻译中的重要技术之一。该文提出了一种重对齐方法,它在IBM models获得的正反双向词对齐的基础上,确定出正反双向对齐不一致的部分。之后,对双向词对齐不一致的部分进行重新对齐以得到更好的对称化的词对齐结果。此外,该文提出的方法还可以利用大规模单语语料来强化对齐结果。实验结果表明,相比在统计机器翻译中广泛使用的基于启发信息的词对齐对称化方法,该文提出的方法可以使统计机器翻译系统得到更高的翻译准确率。     

基于IBM RFID中间件的图书管理系统构建

IBM RFID中间件具有屏蔽RFID硬件设备差异和应用系统差异的特征,这一特征使RFID技术与现有的图书管理系统实现无缝链接的同时,保证了两者的独立性。本文在介绍IBM RFID中间件的基础上,给出了基于IBM RFID中间件的图书馆管理系统,并阐述了系统的工作过程。     

First results with a parallelized 3D weather prediction code

A survey on the parallelization of the 2D model of the Integrated Forecasting System (IFS), the weather prediction code of the ECMWF, is given in this issue [4]. In this short note, we present first results of the parallelization of the corresponding 3D version.     

IBM计算机网络管理策略的研究

本文介绍计算机网络管理的体系结构和协议，分析了ＩＢＭ的计算机网络技术，着重论述了ＩＢＭ的网络管理策略并给出了一个它在某ＣＩＭＳ重点应用工厂的具体应用例。     

8088 development system programmed in C

An 8088 development system is described which combines the advantages of a personal computer (IBM PC), with high-level language support in the form of a c compiler, and a rack-based system. A suite of programs has been developed to enable the c compiler output to be converted into a form suitable for execution on the rack-based target as either ROM- or RAM-resident applications.     

IBM PC／XT外逸电子计数接口电路的设计与实现

外逸电子数目准确检测是智能型外逸电子传感器的关键所在。本文介绍一种ＩＢＭＰＣ／ＸＴ外逸电子计数接口电路的原理和设计方法，并给出了在中断方式下进行数据处理的硬件和软件框图。