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Denial of Service (DoS) attacks consist of overwhelming a server, a network or a Web site in order to paralyze its normal activity. The additional parameter in Distributed Denial of Service (DdoS) attacks is the distributing strategy. It means that DDoS attacks do not come from a single computer but stem from all accessible channels and servers. Consequences are multiple, ranging from system errors, temporary inability to access the Web site for normal users to challenging the actual reliability of the Internet. Despite this, Internet users show carelessness. The explanation lies in the specificities of DDoS attacks. We explore possibilities to raise users' awareness about the actual amplitude of problems caused by DDoS attacks. We suggest a careful examination of Internet pricing mechanisms and switching from flat to usage-constraining pricing schemes. 相似文献
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Gary Harden 《Journal of Financial Services Marketing》2002,6(4):323-332
UK high street banks are continuing to extend the choice of channel through which customers can manage their moneycolon; an obvious example is e-banking. They have been keen to exploit technological advances and changing customer attitudes to alternative channels. Additionally, competition from leaner new market entrants has provided an added incentive to adopt new approaches. In the light of such developments, it is worth reflecting on the changing nature of the bank–customer relationship. This paper suggests that banks are finding it difficult to manage relationships effectively due, in large measure, to the sheer volume of customer data generated by new interactive, technology-based channels. Paradoxically, it seems that the more data banks have about customers the less likely they are to know them on a personal level. It is further suggested that channels such as e-banking potentially reduce the level of personal contact between bank and customer to the extent that a ‘virtual’ relationship develops. This paper concludes that, given the tendency towards ‘virtualisation’, it is inconceivable that bank–customer relationships will become any more intimate in the future. Indeed, a greater degree of personalisation in customer communication may be the very best that banks are able to offer. 相似文献
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A bilinear multivariate errors-in-variables model is considered. It corresponds to an overdetermined set of linear equations
AXB=C, A∈ℝm×n, B∈ℝp×q, in which the data A, B, C are perturbed by errors. The total least squares estimator is inconsistent in this case.
An adjusted least squares estimator is constructed, which converges to the true value X, as m →∞, q →∞. A small sample modification of the estimator is presented,
which is more stable for small m and q and is asymptotically equivalent to the adjusted least squares estimator. The theoretical
results are confirmed by a simulation study.
Acknowledgements. We thank two anonymous reviewers for their suggestions and corrections.? A. Kukush is supported by a postdoctoral research
fellowship of the Belgian office for Scientific, Technical and Cultural Affairs, promoting Scientific and Technical Collaboration
with Central and Eastern Europe.? S. Van Huffel is a full professor with the Katholieke Universiteit Leuven.? I. Markovsky
is a research assistant with the Katholieke Universiteit Leuven.? This paper presents research results of the Belgian Programme
on Interuniversity Poles of Attraction (IUAP V-22), initiated by the Belgian State, Prime Minister's Office – Federal Office
for Scientific, Technical and Cultural Affairs of the Concerted Research Action (GOA) projects of the Flemish Government MEFISTO-666
(Mathematical Engineering for Information and Communication Systems Technology), of the IDO/99/03 project (K.U. Leuven) “Predictive
computer models for medical classification problems using patient data and expert knowledge”, of the FWO projects G.0078.01,
G.0200.00, and G0.0270.02.? The scientific responsibility is assumed by its authors. 相似文献
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Upinder S. Dhillon Dennis J. Lasser Gabriel G. Ramírez 《Review of Quantitative Finance and Accounting》1992,2(2):205-213
This study examines the effect of initiating discount and no discount dividend reinvestment plans on shareholder wealth. The results show a negative response to DRP announcements, which is significantly smaller than that found in studies of new equity offerings. These results are consistent with the Scholes and Wolfson (1989) hypothesis that managers in need of equity capital use DRPs to mitigate the adverse stock price effects of new equity issue announcements. Furthermore, there is a significant difference in the price response of discount and no discount DRPs for industrial firms. This result is supportive of the signaling potential of discount DRPs. Supportive evidence is also found in the analysis of firm characteristics for industrial firms. 相似文献