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Intrusion detection complements intrusion prevention mechanisms, such as firewalls, cryptography, and authentication, to capture intrusions into an information system while they are acting on the information system. We develop two multivariate quality control techniques based on chi‐square and Canberra distance metrics, respectively, to detect intrusions by building a long‐term profile of normal activities in the information system (norm profile) and using the norm profile to detect anomalies. We investigate the robustness of these two distance metrics by comparing their performance on a number of data sets involving different noise levels in data. The performance results indicate that the Chi‐square distance metric is much more robust to noises than the Canberra distance metric. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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Data mining techniques for customer relationship management 总被引:3,自引:0,他引:3
Advancements in technology have made relationship marketing a reality in recent years. Technologies such as data warehousing, data mining, and campaign management software have made customer relationship management a new area where firms can gain a competitive advantage. Particularly through data mining—the extraction of hidden predictive information from large databases—organizations can identify valuable customers, predict future behaviors, and enable firms to make proactive, knowledge-driven decisions. The automated, future-oriented analyses made possible by data mining move beyond the analyses of past events typically provided by history-oriented tools such as decision support systems. Data mining tools answer business questions that in the past were too time-consuming to pursue. Yet, it is the answers to these questions make customer relationship management possible. Various techniques exist among data mining software, each with their own advantages and challenges for different types of applications. A particular dichotomy exists between neural networks and chi-square automated interaction detection (CHAID). While differing approaches abound in the realm of data mining, the use of some type of data mining is necessary to accomplish the goals of today’s customer relationship management philosophy. 相似文献
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Amel Boudelaa Zohra Abdelhafidi Nasreddine Lagraa Chaker Abdelaziz Kerrache Muhammad Bilal Daehan Kwak Mohamed Bachir Yagoubi 《计算机、材料和连续体(英文)》2022,73(2):2495-2512
Vehicular Social Networks (VSNs) is the bridge of social networks and Vehicular Ad-Hoc Networks (VANETs). VSNs are promising as they allow the exchange of various types of contents in large-scale through Vehicle-to-Vehicle (V2V) and Vehicle-to-Infrastructure (V2I) communication protocols. Vehicular Named Data Networking (VNDN) is an auspicious communication paradigm for the challenging VSN environment since it can optimize content dissemination by decoupling contents from their physical locations. However, content dissemination and caching represent crucial challenges in VSNs due to short link lifetime and intermittent connectivity caused by vehicles’ high mobility. Our aim with this paper is to improve content delivery and cache hit ratio, as well as decrease the transmission delay between end-users. In this regard, we propose a novel hybrid VNDN-VSN forwarding technique based on social communities, which allows requester vehicles to easily find the most suitable forwarder or producer among the community members in their neighborhood area. Furthermore, we introduce an effective caching mechanism by dividing the content store into two parts, one for community private contents and the second one for public contents. Simulation results show that our proposed forwarding technique can achieve a favorable performance compared with traditional VNDN, in terms of data delivery ratio, average data delivery delay, and cache hit ratio. 相似文献
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三坐标测量机的数据处理和分析 总被引:4,自引:0,他引:4
数据处理和分析是三坐标测量机应用的核心工作,而基于统计过程控制的SPC技术,则是测量机应用的高级阶段,SPC技术应用的基础性工作是对大量数据的汇总处理。本文提出了一种利用程序方法对数据进行汇总的数学模型和编程思路,结合工作中的经验,对SPC技术的实际应用进行了一些粗浅的探讨。通过使用这些技术和方法,可以实现数据采集、数据处理和数据分析的全程自动化。 相似文献
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DEA cross-efficiency evaluation based on satisfaction degree: an application to technology selection
Data envelopment analysis (DEA) has been extended to cross-efficiency evaluation to provide better discrimination and ranking of decision-making units (DMUs). However, the non-uniqueness of optimal weights in the traditional DEA models (CCR and BCC models) has reduced the usefulness of the DEA cross-efficiency evaluation method. To solve this problem, we introduce the concept of the satisfaction degree of a DMU towards a set of optimal weights for another DMU. Then, a new DEA cross-efficiency evaluation approach, which contains a maxmin model and two algorithms, is proposed based on the satisfaction degrees of the DMUs. Our maxmin model and algorithm 1 can obtain for each DMU an optimal set of weights that maximises the least satisfaction degrees among all the other DMUs. Further, our algorithm 2 can then be used to guarantee the uniqueness of the optimal weights for each DMU. Finally, our approach is applied to a real-world case study of technology selection. 相似文献
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Jacob W. Ulvila John E. Gaffney Jr. 《Journal of research of the National Institute of Standards and Technology》2003,108(6):453-473
This paper presents a comprehensive method for evaluating intrusion detection systems (IDSs). It integrates and extends ROC (receiver operating characteristic) and cost analysis methods to provide an expected cost metric. Results are given for determining the optimal operation of an IDS based on this expected cost metric. Results are given for the operation of a single IDS and for a combination of two IDSs. The method is illustrated for: 1) determining the best operating point for a single and double IDS based on the costs of mistakes and the hostility of the operating environment as represented in the prior probability of intrusion and 2) evaluating single and double IDSs on the basis of expected cost. A method is also described for representing a compound IDS as an equivalent single IDS. Results are presented from the point of view of a system administrator, but they apply equally to designers of IDSs. 相似文献
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Shaomin Wu 《Quality and Reliability Engineering International》2012,28(8):795-805
Warranty claims and supplementary data contain useful information about product quality and reliability. Analysing such data can therefore be of benefit to manufacturers in identifying early warnings of abnormalities in their products, providing useful information about failure modes to aid design modification, estimating product reliability for deciding on warranty policy and forecasting future warranty claims needed for preparing fiscal plans. In the last two decades, considerable research has been conducted in warranty data analysis (WDA) from several different perspectives. This article attempts to summarise and review the research and developments in WDA with emphasis on models, methods and applications. It concludes with a brief discussion on current practices and possible future trends in WDA. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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基于独立成分分析的掌纹识别 总被引:6,自引:0,他引:6
本文研究了独立成分分析(ICA)两种不同的结构ICA I和ICAII在掌纹识别中的应用.为了提高识别准确性和可靠性,该方法首先对掌纹图像进行预处理,提取掌纹感兴趣(ROI)区域进行特征提取和匹配.为了减少计算量,运用ICA算法之前,先采用主成分分析(PCA)算法去除掌纹图像的二阶统计特征相关性,其余的高阶统计特征由ICA分离.对于PolyU掌纹图像库,基于ICA模型的预测误差平方和(SPE)小于PCA,而且重构的原始图像优于PCA.为了比较两种算法识别性能,本丈分别用PCA、ICA I、ICAII提取特征掌纹子空间,然后将待识别图像投影到低维子空间上,最后用余弦距离进行掌纹匹配.实验结果表明,ICA算法两种结构的识别率均高于PCA,ICAII在性能上优于ICA I. 相似文献
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The objective of this research was to develop a decision support framework (DSF) to assess quantitative risk in multimodal green logistics. This risk assessment is the combination of a number of models, the failure mode and effects analysis, the risk contour plot, the quantitative risk assessment, the analytic hierarchy process and the data envelopment analysis which can support a user to perform risk assessment in various decisions. The contribution of this research is that the risk assessment model can generate an optimal green logistics route in accordance with weight from the user. The highlight of this DSF is that the quantitative assessment model can reduce bias on risk assessment of logistics route. An in-depth case study, recommendations, limitations and further research are also provided. 相似文献
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Yujiang Xiang Jasbir S. Arora Salam Rahmatalla Karim Abdel‐Malek 《International journal for numerical methods in engineering》2009,79(6):667-695
A new methodology is introduced in this work to simulate normal walking using a spatial digital human model. The proposed methodology is based on an optimization formulation that minimizes the dynamic effort of people during walking while considering associated physical and kinematical constraints. Normal walking is formulated as a symmetric and cyclic motion. Recursive Lagrangian dynamics with analytical gradients for all the constraints and objective function are incorporated in the optimization process. Dynamic balance of the model is enforced by direct use of the equations of motion. In addition, the ground reaction forces are calculated using a new algorithm that enforces overall equilibrium of the human skeletal model. External loads on the human body, such as backpacks, are also included in the formulation. Simulation results with the present methodology show good correlation with the experimental data obtained from human subjects and the existing literature. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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介绍了一种硅微机械谐振式陀螺仪的结构,给出了调制系数或最大频偏与输入角速度成正比的关系.通过对陀螺仪敏感质量块静电驱动力和双端音叉谐振器输出信号的分析,得出了双端音叉谐振器输出信号的相位差与调制系数之间的关系.提出了一种调频信号最大频偏的检测方法,通过此相位差的计算得出调制系数或最大频差,进而计算出输入角速度的值.设计了一种基于FPGA的数字化解调方案,给出了基于FPGA的数字化最大频差测量电路的测试结果.结果表明测量电路对最大频偏有很好的测量效果. 相似文献
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Bert Ostyn Paul Darius Josse De Baerdemaeker Bart De Ketelaere 《Quality Engineering》2007,19(4):299-310
A multivariate control charting procedure is applied to on-line seal quality evaluation of a packaging process by means of an accelerometer. Based on physical insight it is elucidated in a first step which information in the raw accelerometer data are relevant with respect to the goal of detecting bad seals. Next, a principal component analysis (PCA) based processing of this multivariate information is performed and the related Hotelling's T2 and Q test statistics are calculated for further data representation. In a last step proper control charts based on these statistics are used as a process monitoring tool for on-line distinction between good and bad seals. The obtained results show that a correct monitoring of accelerometer signals can be a useful tool for the on-line detection of 'bad seals' in a packaging process. 相似文献
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Brian McMahon 《Journal of research of the National Institute of Standards and Technology》1996,101(3):347-355
Quality control of the papers in its journals is a major concern of the International Union of Crystallography. Recent technological developments, not least the emergence of a standard data interchange file format, have facilitated the checking of numerical data in a paper, and its error-free transference to the printed page. Consequently, database holdings derived from IUCr journals will be of greater accuracy. Other publishers of crystallographic data may benefit from these innovations. 相似文献
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Activities toward standardization of fracture mechanics tests on carbon fiber-reinforced polymer-matrix (CFRP) composites have recently focused on cyclic fatigue under mode I (tensile opening), mode II (in-plane shear) and mixed-mode I/II loading. Data from recent round robins performed by Technical Committee 4 (TC4) of the European Structural Integrity Society (ESIS) and from preliminary testing of additional CFRP epoxy laminates at the authors’ laboratories are analyzed with different approaches in attempts to reduce scatter and to identify parameters for CFRP structural design. Selected test data comparing load and displacement control for the cyclic fatigue tests are also discussed. Specifically, threshold values from Paris-law data fitting are compared with values from fitting with a modified Hartman–Schijve approach. Independent of the approach used for the analysis, mode I threshold values of selected CFRP seem to be in the range between about 30 and 100 J/m2, i.e., roughly around the range of critical mode I energy release rate values (denoted by GIC) obtained from fracture testing of neat commercial epoxy resins, but clearly below quasi-static initiation GIC-values for unidirectional CFRP composites. Implications for CFRP structural design based on mode I fatigue fracture mechanics test data are briefly discussed. 相似文献