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951.
An Internet-based negotiation server for e-commerce 总被引:6,自引:0,他引:6
Stanley Y.W. Su Chunbo Huang Joachim Hammer Yihua Huang Haifei Li Liu Wang Youzhong Liu Charnyote Pluempitiwiriyawej Minsoo Lee Herman Lam 《The VLDB Journal The International Journal on Very Large Data Bases》2001,10(1):72-90
This paper describes the design and implementation of a replicable, Internet-based negotiation server for conducting bargaining-type
negotiations between enterprises involved in e-commerce and e-business. Enterprises can be buyers and sellers of products/services
or participants of a complex supply chain engaged in purchasing, planning, and scheduling. Multiple copies of our server can
be installed to complement the services of Web servers. Each enterprise can install or select a trusted negotiation server
to represent his/her interests. Web-based GUI tools are used during the build-time registration process to specify the requirements,
constraints, and rules that represent negotiation policies and strategies, preference scoring of different data conditions,
and aggregation methods for deriving a global cost-benefit score for the item(s) under negotiation. The registration information
is used by the negotiation servers to automatically conduct bargaining type negotiations on behalf of their clients. In this
paper, we present the architecture of our implementation as well as a framework for automated negotiations, and describe a
number of communication primitives which are used in the underlying negotiation protocol. A constraint satisfaction processor
(CSP) is used to evaluate a negotiation proposal or counterproposal against the registered requirements and constraints of
a client company. In case of a constraint violation, an event is posted to trigger the execution of negotiation strategic
rules, which either automatically relax the violated constraint, ask for human intervention, invoke an application, or perform
other remedial operations. An Event-Trigger-Rule (ETR) server is used to manage events, triggers, and rules. Negotiation strategic
rules can be added or modified at run-time. A cost-benefit analysis component is used to perform quantitative analysis of
alternatives. The use of negotiation servers to conduct automated negotiation has been demonstrated in the context of an integrated
supply chain scenario.
Received: 30 October 2000 / Accepted: 12 January 2001 Published online: 2 August 2001 相似文献
952.
Formal approaches to the design of interactive systems rely on reasoning about properties of the system at a very high level
of abstraction. Specifications to support such an approach typically provide little scope for reasoning about presentations
and the representation of information in the presentation. In contrast, psychological theories such as distributed cognition place a strong emphasis
on the role of representations, and their perception by the user, in the cognitive process. However, the post-hoc techniques
for the observation and analysis of existing systems which have developed out of the theory do not help us in addressing such
issues at the design stage. Mn this paper we show how a formalisation can be used to investigate the representational aspects
of an interface. Our goal is to provide a framework to help identify and resolve potential problems with the representation
of information, and to support understanding of representational issues in design. We present a model for linking properties
at the abstract and perceptual levels, and illustrate its use in a case study of a ight deck instrument. There is a widespread
consensus that proper tool support is a prerequisite for the adoption of formal techniques, but the use of such tools can
have a profound effect on the process itself. In order to explore this issue, we apply a higher-order logic theorem prover
to the analysis.
Received May 1999 / Accepted in revised form July 2000 相似文献
953.
Caches impose a major problem for predicting execution times of real-time systems since the cache behavior depends on the history of previous memory references. Too pessimistic assumptions on cache hits can obtain worst-case execution time estimates that are prohibitive for real-time systems. This paper presents a novel approach for deriving a highly accurate analytical cache hit function for C-programs at compile-time based on the assumption that no external cache interference (e.g. process dispatching or DMA activity) occurs. First, a symbolic tracefile of an instrumented C-program is generated based on symbolic evaluation, which is a static technique to determine the dynamic behavior of programs. All memory references of a program are described by symbolic expressions and recurrences and stored in chronological order in the symbolic tracefile. Second, a cache hit function for several cache architectures is computed based on a cache evaluation technique. Our approach goes beyond previous work by precisely modelling program control flow and program unknowns, modelling large classes of cache architectures, and providing very accurate cache hit predictions. Examples for the SPARC architecture are used to illustrate the accuracy and effectiveness of our symbolic cache prediction. 相似文献
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956.
教师专业化发展已成为国际教师教育改革的趋势,受到许多国家的重视,也是当下教育改革实践提出的一个具有重大理论意义的课题。而评价是促进教师专业化发展的重要组成部分。本文就传统评价的弊端和建构性评价的优势,提出运用建构性评价来促进教师的专业化发展。 相似文献
957.
该文主要讨论了《计算机一级考试模拟系统》的开发的相关问题。文章首先从实际应用角度出发,论述了开发本系统的意义,接着讨论了该软件系统的结构及开发中应用到的相关技术。最后对本系统在实际应用过程总体情况进行了小结。 相似文献
958.
SUN Feng 《数字社区&智能家居》2008,(30)
系统采用Oracle数据库作为开发平台,VB.net为开发工具研制而成。系统借鉴银行和电力企业信用等级评价的规则,结合水司水费收缴的历史纪录及各客户的实际情况,运用自动采集程序,从原有的营销系统和财务系统自动录入数据,再通过优化的模糊概率、神经网络程序,对用户进行交纳水费信用等级评定,建立客户交纳水费风险预警机制。 相似文献
959.
刘凌 《数字社区&智能家居》2008,(3):1207-1208
为了提供更具可信度的搜索结果以及更高的用户满意度,一个可行的方案是在现行的搜索;引擎的架构上引入用户评价系统。经过改良后的搜索引擎在对搜索结果进行排序时应该不仅仅考虑网址指向因素。同时应该考虑用户评价因素。采用的用户评价系统应该对所有使用者开放,界面应该尽量简单,同时应该对不同的评价给予不同的权重。 相似文献
960.
E. Zhulkova N. Ilyasova A. Kupriyanov A. Plastinin 《Optical Memory & Neural Networks》2008,17(2):152-156
The presented technology of leukocytes determination upon blood preparation images uses the image representation in HSL (Hue,
Saturation, Lightness) color space. The results of experimental research of the technology quality depending on various distortions
on model and real images are described.
The text was submitted by the authors in English. 相似文献