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81.
82.
The transfer of mass flow between ironmaking and steelmaking process at Baoshan Iron and Steel Co. Ltd. has been analyzed. The mathematic-physical models of transport scheduling for hot metal manufacturing have been researched combined with the practical problem in the metallurgical manufacture procedure. Taking into account these models, the scheduling software has been designed, programmed and tested on-line. The new automation system of production scheduling has been implemented successfully at Baosteel, which produces a great economic benefit. 相似文献
83.
DWT-Based Watermarking Scheme for Digital Images 总被引:2,自引:0,他引:2
A watermarking scheme for digital images is introduced. This method is based on discrete wavelet transform and spread spectrum technique. A discrete wavelet transformed binary signature image is expanded by an m-sequence and added to the large wavelet coefficients of a host image with a scale factor. Good balance be-tween transparency and robustness is achieved by the selection of the scale factor. In addition, the spread spec-trum technique is adopted to increase the robustness of this watermarking scheme. The experimental results show that the proposed method is of good performance and robustness for common image operations such as JPEG lossy compression, etc. 相似文献
84.
VPN构建的一种设计思想 总被引:1,自引:0,他引:1
Internet的发展对安全问题的要求越来越高,网络安全日益受到重视。文章以虚拟专用网为主要研究对象,结合软件工程的一些开发思想,对虚拟专用网的构建做出了理论上的设计。文章分析了虚拟专用网目前所涉及的主要几大模型,具体构建了一种可行的VPN设计方案,同时结合软件工程,对VPN构建给出自行设计的一种模块结构图,并对各个模块结构给出了具体解释,今后的工作在于将模块具体细化运用到实践中。 相似文献
85.
Software release management is the process through which software is made available to and obtained by its users. Until now, this process has been relatively straightforward. However, the emergence of component‐based software is complicating software release management. Increasingly, software is constructed via the assembly of pre‐existing, independently produced, and independently released components. Both developers and users of such software are affected by these complications. Developers need to accurately document the complex and changing dependencies among the components constituting the software. Users must be involved in locating, retrieving, and assembling components in order to appropriately bring the software into their particular environment. In this paper, we introduce the problem of release management for component‐based software and discuss SRM, a prototype software release management tool we have developed that supports both developers and users in the software release management process. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
86.
87.
E. Georgiadou 《Cybernetics and Systems Analysis》2003,39(1):125-142
In this paper, a historical overview of significant attempts to get over the software crisis is presented. In particular, we trace the development of lifecycle models and information systems development methodologies during the last four decades. Finally, we explore the role of measurements and outline current and future works leading to process and product improvement. 相似文献
88.
Artificial argument assistants for defeasible argumentation 总被引:3,自引:0,他引:3
The present paper discusses experimental argument assistance tools. In contrast with automated reasoning tools, the objective is not to replace reasoning, but to guide the user's production of arguments. Two systems are presented,
and
based on
. The focus is on defeasible argumentation with an eye on the law. Argument assistants for defeasible argumentation naturally correspond to a view of the application of law as dialectical theory construction. The experiments provide insights into the design of argument assistants, and show the pros and cons of different ways of representing argumentative data. The development of the argumentation theories underlying the systems has culminated in the logical system
that formalizes the interpretation of prima facie justified assumptions.
introduces an innovative use of conditionals expressing support and attack. This allows the expression of warrants for support and attack, making it a transparent and flexible system of defeasible argumentation. 相似文献
89.
基于数字电力系统的地区配电网络统一数据平台的研究 总被引:7,自引:1,他引:7
基于数字电力系统的思想 ,根据地区配电网络的特点 ,对数据进行分类 ,建立关系数据库的组织关系 ,提出了一种利用集合以及图论知识构建地区配电网络统一数据平台的方法 ,确保数据的共享性、一致性、唯一性 ,并符合数字电力系统的要求 ,具有普适性。同时结合实例 ,在该数据平台上 ,利用特征映射的方法 ,进行查询 ,效果令人满意。 相似文献
90.
The aim of magnetization transfer is to saturate the protons of the macromolecule pool with a radiofrequency (RF) pulse leading
to differences in free water pool signal. Magnetization transfer (MT) contrast is difficult to achieve with the echo planar
imaging (EPI) technique, although its short acquisition time would be most beneficial. Indeed, the RF saturation pulses can
only be applied once before sampling the whole k-space in a single-short sequence. A possible solution to improve the sensitivity
of EPI to magnetization transfer consists in applying a train of several saturation RF pulses before image acquisition. The
different parameters of a RF pulse train and their influence on the MT rate have been tested to optimize an EPI clinical sequence.
Our experimental procedure makes it possible to obtain a MT map in about 1 second. The technique is evaluated by multiple
sclerosis lesion characterization.
Supported by grants from the French research ministry and Siemens medical France. 相似文献