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1.
本文对如何构建一个全新的解析智能系统进行了描述。该系统的特点是把基于化学计量学的解析算法和专家系统柔性集成到一起,并把数据库知识发现(KDD)技术和专家数据库(ED)技术作为构建专家系统知识库的核心工具。利用解析算法可使复杂化学体系简化,结合改进的专家系统可实现化学体系定性定量及结构解析的智能化。  相似文献   

2.
为了提高蚁群化学聚类算法的聚类效果,通过引入径向基核函数改进蚁群化学聚类算法的相似度度量式,提出了核蚁群化学聚类算法。将核蚁群化学聚类算法用于三个标准数据集合,计算结果表明与蚁群化学聚类算法相比,核蚁群化学聚类算法聚类效果提升显著。将核蚁群化学聚类算法、核自组织神经网络映射算法和基于多项式核的结构化有向树数据聚类算法同时用于Iris数据集合,结果显示三种核聚类算法聚类效果相当。  相似文献   

3.
蚁群法是继遗传法、模拟退火法和禁忌搜索法之外的又一种新兴,启发式随机搜索算法,该算法是模拟蚂蚁在觅食过程中,能发现蚁巢到食物的最短路径搜索机制而发展起来的,已成功地应用于一系列复杂组合问题的优化。本文主要综述蚁群法的基本原理,以及近5年来在化学化工中的应用情况。首先概述算法的特点,再详尽讨论建立蚁群法模型的有关抽象与近似,指出蚁群法的实现过程;从化学化工过程的优化、化学计量学的研究和催化剂的开发、化学反应动力学参数估算等方面,讨论了算法在化学化工领域中应用情况;最后展望算法在化学化工领域中的应用可能。  相似文献   

4.
VF算法在化学结构检索中的应用   总被引:5,自引:3,他引:2  
实现了一种基于属性关系图的二维子结构匹配算法 (VF算法),该算法运行时所需的存储空间较小,适合于处 理大批量数据。算法程序用Java语言实现,在NCI开放数据库中经过了3DFS程序的检验,并在已建立的化学结构数 据库中作为子结构检索的工具得到了应用。  相似文献   

5.
介绍了神经网络技术的研究现状,特别是在化学领域的应用情况,以及反向传播人工神经网络(BP-ANN)的基本原理和算法.结合波谱解析和化学传感器阵列两个方面对神经网络模式识别技术在化学毒剂侦检领域的应用特点进行了分析.指明了ANN模式识别技术在应用中存在的问题,并对该方向今后的发展提出了建议.  相似文献   

6.
提出了一种基于知识库及自动推理机制的化学反应系统,详细阐述了该自动推理系统的技术架构与算法实现.主要收集了无机化学知识,分析并提取相关化学反应规则,建立了相应的化学知识库,实现了由添加反应物到化学反应生成物的一系列自动推理过程.通过稀硫酸和铁反应实例表明,该系统对开发智能的虚拟实验平台,以及学生运用软件自主学习化学知识,掌握化学规律与现象,具有重要作用.  相似文献   

7.
针对化学数据分类的问题,提出一种用于挖掘化学模式分类提取规则的遗传算法.该算法以样本属性值为条件,采用实值编码方式,将化学分类提取规则演绎成种群进化规则,适应度函数与各参数的设置也以离散型化学数据和连续型化学数据的规则提取为依据.实验结果表明,设计的遗传算法在解决化学模式分类问题上性能良好,易于专业分析.  相似文献   

8.
研究化学智能解题的前提是研究各类符号的录入、识别、理解,这是多媒体教育软件中的一个技术难点。文章讨论了化学学科中特殊符号的录入,并设计出一些算法,这些算法能够从记录一个分子式的数据结构中识别出全部的反应物分子工、生成物分子式、反应条件等,从而能将用户录入的答案与标准答案比较和智能配平。  相似文献   

9.
在化学化工研究中,Markush结构越来越多地用于申请专利保护和报告新发明成果。随着化学化工专利数目的大量增加,对化学化工专利文献的存储和检索的需求日益殷切。为了建立可检索的化学化工专利数据库,迫切需要有效地解决化学化工专利文献中所涉及的Markush结构和其他非确定结构的计算机表示与检索问题。而检索算法是与结构表达紧密联系的。本文在总结前人工作基础上,提出了广义的非确定性化学结构(包括Markush结构)的计算机表达方法。与之相对应的非确定结构的结构识别算法已经实现并在优化中。  相似文献   

10.
大规模化合物子结构检索的并行实现与优化   总被引:3,自引:1,他引:2  
化合物的子结构检索在计算机辅助药物设计、波普学、化学数据库等领域是不可或缺的工具.然而由于子结构检索是一个NP完备性的问题,获得用户可接受的平均检索时间一直是研究人员十分关注的问题,其方法主要有改进算法和提升硬件条件2个方面.当化学结构数据库的规模达到百万乃至千万级别时,尽管改进算法的方式能够获得一定的检索效率提升,但其提升的空间有限,因而,集群并行方式是大规模化合物子结构检索应用的必然选择.本文以Chem D B Portal的化学子结构检索系统为基础,实现了基于集群并行的化学子结构检索系统,并进行了任务均分、多线程并行等优化.在包含800万个化合物结构的化学结构数据库中,利用5个节点的小型集群,选取10个较为典型的提问结构进行子结构检索测试.测试结果为基于集群的化学子结构检索的平均检索时间由初始单节点时的34.1 min降低为2.75 min,检索效率平均提高12.4倍,表明在大规模乃至超大规模的数据条件下,集群并行化方式能够显著地提高子结构检索系统的执行效率.  相似文献   

11.
2006年2月28日,网络安全及电源管理芯片供应商凹凸科技(O2Micro)向中国用户隆重推介凹凸科技在网络安全领域的独特理念和全新方案.此举标志着凹凸科技已正式进军网络安全领域.特别在ASIC防火墙和SSL VPN技术和产品的竞争中,凹凸科技已经担负了不可或缺的重要角色.而其在模拟与数字集成电路方面拥有的强大设计和制造能力,无疑将为其最终成为全球网络安全领域的主要供应商增加关键筹码.凹凸科技在评述中国安全市场发展趋势的同时,还将携两款最具代表性的成熟产品--ASIC防火墙SifoWorks和SSL VPN产品Succendo一起亮相.  相似文献   

12.
继成功举办2005年Sun JAVA中国开发者大会之后,Sun一年一度全球规模的开发者大会——2006Sun科技日又分别于今年9月23~24日和27~28日相继在中国上海和北京两大都市举行“。Java之父”James Gosling再次来到中国,与中国的开发者讨论软件开发者所关心的问题,讲述Sun的软件发展策略、介绍Solaris10操作系统的独特的特性和新的Java开发工具、展望Java技术发展前景,特别是阐明Sun实施Java技术开源的策略。Sun科技日是Sun公司最重要的全球开发者的大会,它针对Java技术、Solaris10OS、NetBeans、OpenSolaris、开源技术、开发工具和Web…  相似文献   

13.
2006年3月15日,“陕西省第一届国防科工系统内网信息安全建设专题研讨会”在西安市隆重召开。此次会议的议题是,在当前的信息安全形势下,陕西省国防科工系统内网面临的信息安全问题,以及如何采取有效的解决方案进一步提高国家机要部门内部网络的安全保护等级,以适应形势发展的需要。此次会议由陕西省国防科工委主办,陕西省国防科工委信息中心和北京榕基网安科技有限公司、北京理工先河科技发展有限公司、陕西金叶西工大共同承办,国家保密局和陕西省国防科工委的有关领导出席会议并发表了重要讲话。在为期两天的会议中,共有100多名国防科工系…  相似文献   

14.
Abstract This paper outlines the consensual approach to the formulation of curriculum policy in general, and in relation to information technology (IT) in particular, in Scotland. It outlines the approaches to IT that have emerged as a result. These are founded on the premises that all children should develop knowledge and understanding about IT and skills in using IT; that IT should influence both content and delivery of the curriculum; and that IT (computing studies in Scotland) should be an elective for secondary school pupils. Against this background, the paper describes the evolution of policy and practice relating to IT in teacher education. It appraises the strategies which institutes are using for developing the professional skills necessary to deliver IT in the Scottish curriculum. It notes significant progress but highlights the need to develop strategies which integrate IT more deeply with other professional studies so that student teachers develop deeper, more reflective approaches to IT.  相似文献   

15.
Abstract This paper charts the developments in information technology (IT) policies in education in Japan over the past decade with particular emphasis on the impacts on teacher education. Beginning with the work of the National Council on Educational Reform in 1985, the Japanese education system initiated a thorough analysis of the role of information technology in all aspects of education from kindergarten through to high school, vocational education and pre- and in-service teacher education. The various approaches culminated in guidelines and statutory requirements relating to both schools' curricula and teacher training, published in the period 1990–1992. More recently other ministries have contributed to developments including the Ministry for International Trade and Industry which has categorized the different types of information engineers and among these is the new Educational Engineer. The paper reports the processes leading to these developments.  相似文献   

16.
Abstract To understand what is going on in France at the moment in the domain of computers and related communication technologies in teacher training, there are two major developments that have to be kept in mind. Firstly, the ways of becoming a teacher in France underwent major changes in 1991. It is therefore too early to come to general conclusions about the effects of this reform in the field of new information technologies. Secondly, French IT in schools policy has shifted from a large-scale centralized equipment operation, which provided microcomputers in each school from 1985 to 1987, to a more regional management of equipment funding, with less national piloting in the field. This paper describes what happened during the previous period and what is taking place now. With matters still evolving the paper represents a snapshot rather than an exhaustive survey; such a survey remains to be done.  相似文献   

17.
Abstract In 1988 the eleven West-German Kultusminister , with responsibility for the school systems in their respective Bundeslaender , reached agreement with the Federal Ministry of Education and Science on the broad concept of 'Information and Communications Technology', ITG. After four years of discussion it was agreed that ITG should be introduced into the secondary level of the general schools. In spite of strong disagreements about the ways and speed of implementation, and after several years of experiments, important parts of the concept have become a reality in practically all of the old Bundeslaender. While acknowledging the complexity of the German educational system the paper attempts to outline the development of the concept of Information and Communications Technology and its consequences in teacher education. The development in the eastern part of Germany, the former GDR, has been completely different to that in the western part and this is also commented upon in the paper.  相似文献   

18.
Abstract As with many European countries Denmark is experiencing change in teacher education and most notably in the wake of an act of government in 1992 which was designed to set out common aims for teacher education. Prior to that the content and structure of teacher education had been highly specified including, for example, the requirement that student teachers should take a course of 42 hours IT-related lessons. This paper provides a brief history of the background to the changes in teacher education and focuses on the implications that the more flexible aims for teacher education have for the future integration of IT in teacher education.  相似文献   

19.
在网络层实现安全传输通道技术的研究   总被引:3,自引:0,他引:3  
安全传输通道是对传输的原始信息进行加密和协议封装处理,从而实现安全传输的技术,本文在TCP/IP的网络层上提出了实现安全传输通道的技术和解决方案。并对网络层的安全传输通道技术提出了实现机制。  相似文献   

20.
《Ergonomics》2012,55(7):853-865
Ergonomic thought and practice were introduced in ancient China in relation to modern developments in Chinese ergonomics. Despite the ten-year interruption of the 'cultural revolution’ in the late 1960s and 1970s, ergonomics has made great progress in China in the last decade. In this paper some general developments in recent ergonomics’ teaching and in professional organizations are described. Four major areas of ergonomics research are illustrated: (1) Visual displays and signal design; (2) Human-computer interface with Chinese computers; (3) Cognitive strategies and decision support; (4) Mental workload and occupational stress. The main characteristics of Chinese ergonomics are discussed and new directions are highlighted, based on recent developments and progress.  相似文献   

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