986 resultados para Spam filtering (Electronic mail)


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In the last decade, the rapid growth of the Internet and email, there has been a dramatic growth in spam. Spam is commonly defined as unsolicited email messages and protecting email from the infiltration of spam is an important research issue. Classifications algorithms have been successfully used to filter spam, but with a certain amount of false positive trade-offs, which is unacceptable to users sometimes. This paper presents an approach to overcome the burden of GL (grey list) analyzer as further refinements to our multi-classifier based classification model (Islam, M. and W. Zhou 2007). In this approach, we introduce a ldquomajority voting grey list (MVGL)rdquo analyzing technique which will analyze the generated GL emails by using the majority voting (MV) algorithm. We have presented two different variations of the MV system, one is simple MV (SMV) and other is the ranked MV (RMV). Our empirical evidence proofs the improvements of this approach compared to the existing GL analyzer of multi-classifier based spam filtering process.

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"November-December 1988."

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v.1 Summary -- v. 2. Frequency allocations and network designs -- v.3 Technology studies

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This exploratory study of a classroom with mentoring and neutral e-mail was conducted in a public commuter state university in South Florida between January 1996 and April 1996. Sixteen males and 83 females from four graduate level educational research classes participated in the study.^ Two main hypotheses were tested. Hypothesis One was that those students receiving mentoring e-mail messages would score significantly higher on an instrument measuring attitude toward educational research (ATERS) than those not receiving mentoring e-mail messages. Hypothesis Two was that those students receiving mentoring e-mail would score significantly higher on objective exams covering the educational research material than those not receiving mentoring e-mail.^ Results of factorial analyses of variance showed no significant differences between the treatment groups in achievement or in attitudes toward educational research. Introverts had lower attitudes and lower final exam grades in both groups, although introverts in the mentored group scored higher than those introverts in the neutral group.^ A t test of the means of total response to e-mail from the researcher showed a significant difference between the mentored and neutral e-mail groups. Introverts responded more often than extraverts in both groups.^ Teacher effect was significant in determining class response to e-mail messages. Responses were most frequent in the researcher's classes.^ Qualitative analyses of the e-mail and course evaluation survey and of the content of e-mail messages received by the researcher were then grouped into basic themes and discussed.^ A qualitative analysis of an e-mail and course evaluation survey revealed that students from both the neutral and mentoring e-mail groups appreciated teacher feedback. A qualitative analysis of the mentoring and neutral e-mail replies divided the responses into those pertaining to the class, such as test and research paper questions, and more personal items, such as problems in the class and personal happenings.^ At this point in time, e-mail is not a standard way of communicating in classes in the college of education at this university. As this technology tool of communication becomes more popular, it is anticipated that replications of this study will be warranted. ^

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电子邮件(Electronic Mail,E-Mail)是目前使用最广泛的互联网应用。随着互联网络以惊人的速度增长,电子邮件成为发布恶意信息的一个重要途径,垃圾邮件已经成为危害互联网络的最大毒瘤。针对方式多样的垃圾邮件技术,垃圾邮件过滤系统往往也需要综合多种过滤技术以提高系统的有效性。其中摘要技术已经成为重要的垃圾邮件过滤方法之一:通过摘要技术判断一个邮件和已知垃圾邮件的相似度,从而对邮件进行分类。判断一个垃圾邮件过滤算法是否有效,要综合考虑算法的召回率、准确率以及时间性能。I-Match算法通过摘要值的精确匹配来判断两个邮件文本内容是否相似,算法在效率方面表现突出。但是I-Match算法在实际的应用中还存在很多问题,其中包括字典生成制约算法的性能以及面对攻击时算法表现出的鲁棒性不足。因此,优化算法的字典生成过程以及提高算法的鲁棒性成了算法应用于实际系统的两个重要问题。本文的主要工作包含以下内容: 对垃圾邮件进行相似性分析,包括垃圾邮件相似性的起因、垃圾邮件在时间和内容两方面所表现出的相似性特征。垃圾邮件体现出的相似性特征是使用摘要算法进行垃圾邮件过滤的必要条件之一。 改进I-Match算法的字典生成过程。提出利用特征的互信息作为特征选择依据改进字典生成过程,并对比几种不同的特征选择方式对算法性能的影响。 分析I-Match算法的鲁棒性以及几种I-Match改进算法对算法鲁棒性的提升,在实际的邮件语料上对各种改进算法进行评测,并综合分析各个算法的实用性。 完成了KSpam系统原型,以插件的形式综合多种邮件过滤方法,并给出了I-Match算法在KSpam系统中的实现方案。同时,系统实现了一种新式的邮件自动回收功能,有效减少邮件管理员的邮件语料收集工作。

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Currently mobile spam has been a major menace to the development of wireless networks. In this paper, the mobile spam problem and its countermeasures are analysed. In particular, we propose a Support Vector Machine to filter mobile spam. This mobile spam filtering system can be deployed in current wireless networks and achieve good performance in protecting end users and operators from mobile spam. Legislation issues and challenges to defend mobile spam are also discussed in the latter part of this paper.

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Spams and Phishing Scams are some of the abuse forms on the Internet that have grown up now. These abuses influence in user's routine of electronic mail and in the infrastructure of Internet communication. So, this paper proposes a new model messages filter based in Euclidian distance, beyond show the containment's methodologies currently more used. A new model messages filter, based in frequency's distribution of character present in your content and in signature generation is described. An architecture to combat Phishing Scam and spam is proposed in order to contribute to the containment of attempted fraud by mail.

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Pós-graduação em Engenharia Elétrica - FEIS

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Many data mining techniques have been proposed for mining useful patterns in text documents. However, how to effectively use and update discovered patterns is still an open research issue, especially in the domain of text mining. Since most existing text mining methods adopted term-based approaches, they all suffer from the problems of polysemy and synonymy. Over the years, people have often held the hypothesis that pattern (or phrase) based approaches should perform better than the term-based ones, but many experiments did not support this hypothesis. This paper presents an innovative technique, effective pattern discovery which includes the processes of pattern deploying and pattern evolving, to improve the effectiveness of using and updating discovered patterns for finding relevant and interesting information. Substantial experiments on RCV1 data collection and TREC topics demonstrate that the proposed solution achieves encouraging performance.

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The presence of spam in a document ranking is a major issue for Web search engines. Common approaches that cope with spam remove from the document rankings those pages that are likely to contain spam. These approaches are implemented as post-retrieval processes, that filter out spam pages only after documents have been retrieved with respect to a user’s query. In this paper we suggest to remove spam pages at indexing time, therefore obtaining a pruned index that is virtually “spam-free”. We investigate the benefits of this approach from three points of view: indexing time, index size, and retrieval performances. Not surprisingly, we found that the strategy decreases both the time required by the indexing process and the space required for storing the index. Surprisingly instead, we found that by considering a spam-pruned version of a collection’s index, no difference in retrieval performance is found when compared to that obtained by traditional post-retrieval spam filtering approaches.

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This research project examined the diffusion of change within one Victorian TAFE Institute by engaging action research to facilitate implementation of e-mail technology. The theoretical framework involving the concepts of technology innovation and action research was enhanced with the aid of Rogers's (1983) model of the diffusion of the innovation process. Political and cultural factors made up the initiation phase of innovation, enabling the research to concentrate on the implementation phase of e-mail Roger's (1983) model also provided adopter categories that related to the findings of a Computer Attitude Survey that was conducted at The School of Mines and Industries Ballarat (SMB), now the University of Ballarat—TAFE Division since amalgamation on 1st January 1998. Despite management rhetoric about the need to utilise e-mail, Institute teaching staff lacked individual computers in their work areas and most were waiting to become connected to the Internet as late as 1997. According to the action research reports, many staff were resistant to the new e-mail facilities despite having access to personal computers whose numbers doubled annually. The action research project became focussed when action researchers realised that e-mail workshop training was ineffective and that staff required improved access. Improvement to processes within education through collaborative action research had earlier been achieved (McTaggart 1994), and this project actively engaged practitioners to facilitate decentralised e-mail training in the workplace through the action research spiral of planning, acting, observing and reflecting, before replanning. The action researchers * task was to find ways to improve the diffusion of e-mail throughout the Institute and to develop theoretical constructs. My research task was to determine whether action research could successfully facilitate e-mail throughout the Institute. A rich literature existed about technology use in education, technology teaching, gender issues, less about computerphobia, and none about 'e-mailphobia \ It seemed appropriate to pursue the issue of e-mailphobia since it was marginalised, or ignored in the literature. The major political and cultural influences on the technologising of SMB and e-mail introduction were complex, making it impossible to ascertain the relative degrees of influence held by Federal and State Governments, SMB's leadership or the local community, Nonetheless, with the implementation of e-mail, traditional ways were challenged as SMB's culture changed. E-mail training was identified as a staff professional development activity that had been largely unsuccessful. Action research is critical collaborative inquiry by reflective practitioners who are accountable for making the results of their inquiry public and who are self-evaluating of their practice while engaging participative problem-solving and continuing professional development (Zuber-Skerritt 1992, 1993). Action research was the methodology employed in researching e-mail implementation into SMB because it involved collaborative inquiry with colleagues as reflective practitioners. Thoughtful questions could best be explored using deconstructivist philosophy, in asking about the noise of silence, which issues were not addressed, what were the contradictions and who was being marginalised with e-mail usage within SMB. Reviewing literature on action research was complicated by its broad definition and by the variability of research (King & Lonnquist 1992), and yet action research as a research methodology was well represented in educational research literature, and provided a systematic and recognisable way for practitioners to conduct their research. On the basis of this study, it could be stated that action research facilitated the diffusion of e-mail technology into one TAFE Institute, despite the process being disappointingly slow. While the process in establishing the action research group was problematic, action researchers showed that a window of opportunity existed for decentralised diffusion of e-mail training,in preference to bureaucratically motivated 'workshops. Eight major findings, grouped under two broad headings were identified: the process of diffusion (planning, nature of the process, culture, politics) and outcomes of diffusion (categorising, e-mailphobia, the survey device and technology in education). The findings indicated that staff had little experience with e-mail and appeared not to recognise its benefits. While 54.1% did not agree that electronic means could be the preferred way to receive Institute memost some 13.7% admitted to problems with using the voice answering service on telephones. Some 43.3% thought e-mail would not improve their connectedness (how they related) to the Institute. A small percentage of staff had trouble with telephone voice-mail and a number of these were anxious computer users. Individualised tuition and peer support proved helpful to individual staff whom action researchers believed to be 'at risk', as determined from the results of a Computer Attitude Survey. An instructional strategy that fostered the development of self-regulation and peer support was valuable, but there was no measure of the effects of this action research program, other than in qualitative terms. Nevertheless, action research gave space to reflect on the nature of the underlying processes in adopting e-mail. Challenges faced by TAFE action researchers are integrally affected by the values within TAFE, which change constantly and have recently been extensive enough to be considered as a 'new paradigm'. The influence of competition policy, the training reform agenda and technologisation of training have challenged traditional TAFE values. Action research reported that many staff had little immediate professional reason to use e-mail Theoretical answers were submerged beneath practical professional concerns, which related back to how much time teachers had and whether they could benefit from e-mail. A need for the development of principles for the sound educational uses of e-mail increases with the internationalisation of education and an increasing awareness of cultural differences. The implications for conducting action research in TAFE are addressed under the two broad issues of power and pedagogy. Issues of power included gaining access, management's inability to overcome staff resistance to technology, changing TAFE values and using technology for conducting action research. Pedagogical issues included the recognition of educational above technological issues and training staff in action research. Finally, seventeen steps are suggested to overcome power and pedagogical impediments to the conduct of action research within TAFE. This action research project has provided greater insight into the difficulties of successfully introducing one culture-specific technology into one TAFE Institute. TAFE Institutes need to encourage more action research into their operations, and it is only then that -we can expect to answer the unanswered questions raised in this research project.