基于基因表达式编程的频繁函数集挖掘

函数挖掘旨在从观测数据中发现有效的函数关系，传统的函数挖掘以发现单个函数为挖掘目标，难以处理复杂数据集．为解决上述问题，作者做了如下工作：（1）提出了描述能力更强的频繁函数集FFS概念；（2）提出并实现了基于基因表达式编程的频繁函数集挖掘算法FFSM（3）在GEP中采用了精度阈值队列策略PTQ，有效地提高了FFSM的成功率；（4）用实验证实了FFS更强的描述能力和PTQ的有效性，其中，在挖掘高精度复杂函数时PTQ使FFSM的成功率提高了55倍．     

基于动态种群的GEP函数挖掘算法研究

对样本数据进行函数挖掘是GEP研究的一个重要内容.传统的GEP算法往往容易陷入局部最优,为了解决这个问题,本文在动态种群生成策略的基础上,提出了基于动态种群的GEP函数挖掘算法(FMGEP-DP).实验表明,无论是在噪声数据不大的情况下,还是对于函数类型未知且复杂的数据,与传统的GEP和GP相比,FMGEP-DP的收敛速度要快,函数挖掘成功率要高.     

基于网格服务的GEP分布式函数挖掘算法

提出了一种基于网格服务的GEP分布式函数挖掘算法(DFMGEP-GS),它将网格服务与GEP算法相结合,既成功地实现了在网格平台下的GEP函数挖掘,又提高了每个网格节点上GEP算法的全局寻优性;同时证明了在网格环境下由局部数据模型生成全局数据模型的方法.仿真实验结果表明,对于函数类型已知的数据,随着数据集的增大,在成功挖掘到目标函数的情况下,DFMGEP-GS算法的平均耗时最少,而且随着网格节点的增加,DFMGEP-GS的收敛速度最大提高了约17倍;对于函数类型未知的复杂数据集,DFMGEP-GS算法挖掘所得到的模型的误差最小.     

基于GEP的多因子曲线拟合

本文融合了基于数据点拟合的公式发现和因式分解技术,提出并实现了基于基因表达式编程(Gene Expression Programming ,GEP)的多因子曲线拟合MFF（Multiple Factor Fitting）。利用MFF算法能够直接由客观数据挖掘出多个多项式乘积形式的函数关系公式以拟合原始数据集所表示的曲线。MFF中采用了有特色的概率相关系数对GEP中的适应度函数进行优化,使得精度提高了27%。同时采用阈值递减序列TDQ（Threshold Degression Queue）使得GEP成功率比传统技术提高了最大58倍。     

基于基因表达式编程的信用评估模型挖掘方法

提出了一种基于基因表达式编程(GEP)的信用评估模型挖掘方法GEP-CREDIT。该方法基于客户信贷数据，利用GEP算法自动进行属性筛选，并进行属性融合，在此基础上训练和建立信用评估模型。在德国信用数据库真实数据集上做的实验和性能分析表明,基于GEP的信用评估模型挖掘方法较Nave Bayes算法的预测精度提高了3%；较SVM算法的预测精度提高了1.6%；较KNN(K=17)算法的预测精度提高了6.83%。     

新型ε-不敏感损失函数支持向量诱导回归算法及售后服务数据模型预测系统

对含有噪声的数据序列根据预测置信度进行去噪处理，将训练集和测试集及预测数据共同作为训练向量集，以此建立新型支持向量诱导回归算法。本文利用该算法对实时售后服务的“千车故障数”进行了时间序列分析，并建立了新型的ε-不敏感损失函数小样本模型预测系统。预测显示误差小于5．3％的值占了总体的98．1％，其预测置信度达到0．983，与二次和Huber损失函数相比其MAPE值只有2．3％。用计算机模拟仿真单批次预测显，当时间参量t→＋∞，“千车故障数”将收敛于定值74．0601，这和实际相当吻合，表明所建预测模型的有效性。文章最后还和传统神经网络模型作了比较，说明新型SVM机比神经网络处理小样本能力更强。     

基于基因表达式编程的知识发现--沿革、成果和发展方向

综述了基于基因表达式编程(Gene Expression Programming，GEP)的知识发现技术的沿革、特色和成果。剖析了GEP中通过简单编码解决复杂问题的关键技术。特别介绍了在这一领域的工作成果，如基于GEP的多项式因式分解，频繁函数挖掘，抗噪声数据的函数挖掘，太阳黑子预测等。对进一步开展基于GEP的知识发现技术的发展策略提出了自己的见解。     

一个保护隐私信息挖掘算法的错误率分析

对文献[1]中影响保护隐私挖掘算法准确率的变换概率进行分析，并给出变换概率与挖掘算法准确性之间的关系式。计算表明，从10000个事务的数据集中，选取样本的数据量超过数据集10％所产生的关系式，其相对误差，即用该关系式算出变换概率代人基于随机响应技术的挖掘算法产生的误差与希望达到的误差相比，不超过6％；并通过计笋表明关系式的相对误差，随数据集规模的增加而减少。因此，该挖掘算法能适用于实际问题的需要。     

四维飞行轨迹预测方法的研究

通过对空中交通运输管理中目前常用的轨迹预测算法的研究比较和分析,提出了利用遗传算法的从历史数据中进行函数挖掘的思想.针对四维轨迹数据特征的分析和传统的单一函数挖掘的局限性,提出了基于基因表达式编程的频繁函数集挖掘的建模方法.该模型方法通过对历史飞行数据进行遗传算法的操作挖掘出数据集中对应的函数关系集合,用较好的函数模型预测未来航迹.以某一航班雷达数据为训练集做实验,结果表明了应用该方法的准确性和可用性.     

DC-GEP:基因表达式编程早熟预警——多样性贡献策略

基因表达式编程(gene expression programming,GEP)是函数发现的有力工具,但传统的GEP存在早熟缺陷,为了解决这一问题,已有的研究方法均是在早熟发生后采取补救的措施,导致效率的降低。采用了预警思路来防止GEP早熟现象的发生。主要工作如下:(1)通过对种群个体多样性的评价,提出基于多样性贡献的最优个体选择机制,设计了基于融合适应度和多样性贡献的GEP进化算法diversity contribution-GEP(DC-GEP);(2)提出了一种进化辈数自动确定的方法,实现了自适应的DC-GEP进化算法;(3)实验表明,DC-GEP对于复杂函数挖掘的算法性能比标准GEP在进化效率上平均提高了70%。     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

View-based model-driven architecture for enhancing maintainability of data access services

In modern service-oriented architectures, database access is done by a special type of services, the so-called data access services (DAS). Though, particularly in data-intensive applications, using and developing DAS are very common today, the link between the DAS and their implementation, e.g. a layer of data access objects (DAOs) encapsulating the database queries, still is not sufficiently elaborated, yet. As a result, as the number of DAS grows, finding the desired DAS for reuse and/or associated documentation can become an impossible task. In this paper we focus on bridging this gap between the DAS and their implementation by presenting a view-based, model-driven data access architecture (VMDA) managing models of the DAS, DAOs and database queries in a queryable manner. Our models support tailored views of different stakeholders and are scalable with all types of DAS implementations. In this paper we show that our view-based and model driven architecture approach can enhance software development productivity and maintainability by improving DAS documentation. Moreover, our VMDA opens a wide range of applications such as evaluating DAS usage for DAS performance optimization. Furthermore, we provide tool support and illustrate the applicability of our VMDA in a large-scale case study. Finally, we quantitatively prove that our approach performs with acceptable response times.     

A pragmatic multi-method investigation of discrepant technological events: Coping,attributions, and ‘accidental’ learning

Discrepant technological events or situations that entail a problem, a misunderstanding or a difficulty with the Information Technology (IT) being employed, are common in the workplace, and can lead to frustration and avoidance behaviors. Little is known, however, about how individuals cope with these events. This paper examines these events by using a multi-method pragmatic approach informed by coping theory. The results of two studies – a critical incident study and an experiment – serve to build and test, respectively, a theoretical model that posits that individuals use a variety of strategies when dealing with these events: they experience negative emotions, make external attributions, and adopt engagement coping strategies directed at solving the event, eventually switching to a disengagement coping strategy when they feel they have no control over the situation. Furthermore, users’ efforts may result in ‘accidental’ learning as they try to overcome the discrepant IT events through engagement coping. The paper ends with a discussion of the results in light of existing literature, future opportunities for research, and implications for practice.     

Call for Papers The 6^th International Conference on Grid and Cooperative Computing

Recent years have seen rapid advances in various grid-related technologies, middleware, and applications. The GCC conference has become one of the largest scientific events worldwide in grid and cooperative computing. The 6th international conference on grid and cooperative computing (GCC2007) Sponsored by China Computer Federation (CCF),Institute of Computing Technology, Chinese Academy of Sciences (ICT) and Xinjiang University ,and in Cooperation with IEEE Computer Soceity ,is to be held from August 16 to 18, 2007 in Urumchi, Xinjiang, China.     

The Distributed Time-Triggered Simulation Scheme: Core Principles and Supporting Execution Engine

Distributed real-time simulation is a young technology field but its practice is under increasing demands. In recent years the author and his collaborators have been establishing a new approach called the distributed time-triggered simulation (DTS) scheme which is conceptually simple and easy to use but widely applicable. The concept was initiated in the course of developing a new-generation object-oriented real-time programming scheme called the time-triggered message-triggered object (TMO) programming scheme. Some fundamental issues inherent in distributed real-time simulation that were learned during recent experimental studies are discussed along with some approaches for resolving the issues. An execution engine developed to support both the TMOs engaged in control computation and the TMOs engaged in DTS is also discussed along with its possible extensions that will enable significantly larger-scale DTSs.     

Software-Konfigurationsmanagement in großen Softwareprojekten

Zusammenfassung Mit zunehmender Größe der Softwaresysteme verschärfen sich die für die Software-Herstellung typischen Probleme: Beherrschen großer Objektmengen, Erhalten der Systemkonsistenz, Kontrolle der ständigen Änderungseinflüsse und Gewährleisten einer langen Lebensdauer. Die Disziplin Konfigurationsmanagement bildet den methodischen Ansatz, diese Probleme besser zu beherrschen. Software-Konfigurationsmanagement faßt die Herstellung von Softwaresystemen als eine Abfolge von kontrollierten Änderungen an gesicherten Zwischen- und Endergebnissen auf. Dargestellt werden die Objekte und Funktionen des Software-Konfigurationsmanagements sowie die hierfür in großen Software-Projekten benötigten Methoden, Instanzen und Hilfsmittel.     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and     

Editorial:Brain-machine interface(BMI) and cyborg intelligence

正Brain-machine interfaces(BMIs)aim at building a direct communication pathway between the brain and an external device,and represent an area of research where significant progress has been made during the past decade.Based on BMIs,mind information can be read out by neural signals to control     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and overseas to the world’s scientific circles,especially to stimulate     

SCIENCE CHINA Information Sciences SUBJECT INDEX TO VOLUME 57(2014)

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