Construction and Traversal of Hash Chain with Public Links

Current hash chain traversal techniques require that the intermediate links of the hash chain be stored secretly on a trusted storage. This requirement is undesirable in several applications. We propose a new construction of hash chains based on inserting a ‘breakpoint’ after fixed number of links in the chain. We also propose a method with which the current hash chain traversal techniques can be applied to our construction without any significant changes in the storage and computation requirements and with the added advantage that the intermediate links may be stored on a public and non-trusted storage. We are also able to prove the security of our construction by replacing the hash function with a MAC function

Deteção de anomalias em modelos de publicidade Pay-Per-Click

Dissertação de mestrado em Engenharia InformáticaNowadays, online advertisement is one of the most effective and profitable marketing strategies. An example of strong growth in online advertisement is the Pay-Per-Click Advertising Model where all parties are benefited. Due to the number of stakeholders and the amount of money involved, it is inevitable to find efficient methods to analyse the validity of clicks on online advertising, specifically in Pay-Per-Click. The confidence of the advertiser is a crucial point to the success of this model. So it is necessary the distinction between the valid and the invalid clicks, made with the intention of generating charges, benefiting directly or indirectly with that action. Therefore, a state of the art about fraud detection techniques in Pay-Per-Click will be presented, as well as the main techniques used to deceive this advertising model. Other related matters were subject of study, such as the relevant data to collect for an accurate analysis of data flow at the servers. It was performed a comparative analysis of different approaches of anomaly detection in order to identify the most suitable for the problem at hand. Using this subarea of Data Mining, very satisfactory results have been achieved, thus concluding that anomaly detection can give a major contribution to the resolution of Pay-Per-Click fraud.Os anúncios online são atualmente uma das estratégias de marketing mais rentáveis e eficientes. Um exemplo de forte crescimento nesta área é o modelo de publicidade Pay-Per-Click, onde todos os intervenientes são beneficiados. Devido ao número de intervenientes e à quantidade de dinheiro envolvido, torna-se inevitável encontrar métodos eficientes para analisar a validade dos cliques efetuados em publicidade online, mais concretamente em sistemas Pay-Per-Click. A confiança do anunciante é um fator crucial para o sucesso deste modelo. Assim, é necessário distinguir os cliques válidos dos inválidos, feitos com a intenção de gerar um débito, beneficiando direta ou indiretamente com essa ação. Deste modo, será apresentado um estado da arte sobre técnicas de deteção de fraude em Pay-Per-Click, assim como as principais técnicas utilizadas para defraudar esse tipo de modelo. Outros assuntos relacionados foram também objeto de estudo, tal como os dados necessários para uma análise precisa do fluxo de dados nos servidores. Foi efetuado uma análise comparativa de diferentes abordagens de deteção de anomalias a fim de identificar quais as mais adequadas para o problema em questão. Com recurso a esta subárea de Data Mining foram alcançados resultados bastantes satisfatórios, concluindo-se assim que a deteção de anomalias pode dar um contributo fundamental para a resolução de fraude em Pay-Per-Click

Teak: A Novel Computational And Gui Software Pipeline For Reconstructing Biological Networks, Detecting Activated Biological Subnetworks, And Querying Biological Networks.

As high-throughput gene expression data becomes cheaper and cheaper, researchers are faced with a deluge of data from which biological insights need to be extracted and mined since the rate of data accumulation far exceeds the rate of data analysis. There is a need for computational frameworks to bridge the gap and assist researchers in their tasks. The Topology Enrichment Analysis frameworK (TEAK) is an open source GUI and software pipeline that seeks to be one of many tools that fills in this gap and consists of three major modules. The first module, the Gene Set Cultural Algorithm, de novo infers biological networks from gene sets using the KEGG pathways as prior knowledge. The second and third modules query against the KEGG pathways using molecular profiling data and query graphs, respectively. In particular, the second module, also called TEAK, is a network partitioning module that partitions the KEGG pathways into both linear and nonlinear subpathways. In conjunction with molecular profiling data, the subpathways are ranked and displayed to the user within the TEAK GUI. Using a public microarray yeast data set, previously unreported fitness defects for dpl1 delta and lag1 delta mutants under conditions of nitrogen limitation were found using TEAK. Finally, the third module, the Query Structure Enrichment Analysis framework, is a network query module that allows researchers to query their biological hypotheses in the form of Directed Acyclic Graphs against the KEGG pathways

The balanced scorecard approach as a web site evaluation tool : a qualitative analysis of 5-star lodges in South Africa

Please read the abstract in the section 00front of this dissertation. CopyrightDissertation (MCom)--University of Pretoria, 2010.Marketing ManagementMComUnrestricte

Critical analysis of advertising and strategic media planning in FMCG Sector in India

Not availabl

Big Data Security (Volume 3)

After a short description of the key concepts of big data the book explores on the secrecy and security threats posed especially by cloud based data storage. It delivers conceptual frameworks and models along with case studies of recent technology

NASA Tech Briefs, June 1992

Topics covered include: New Product Ideas; Electronic Components and Circuits; Electronic Systems; Physical Sciences; Materials; Computer Programs; Mechanics; Machinery; Fabrication Technology; Mathematics and Information Sciences; Life Sciences

Perfecting Patent Prizes

A number of commentators in recent years have suggested permitting holders of intellectual property rights to give up these rights in exchange for cash prizes from the government. In this Article, Professor Abramowicz shows that each of the proposals has significant flaws that would make implementation impractical and argues that no single perfect formula or algorithm for determining the size of prizes exists. A prize system is nonetheless worth pursuing because it could increase social welfare significantly by eliminating deadweight loss. Professor Abramowicz recommends a relatively simple approach that would complement rather than replace the patent system. The proposal is to establish an agency to distribute a fund that would be used to reward corporate efforts to reduce the monopoly effects of patent rights. As long as there is a substantial delay between the activities reducing deadweight loss and the granting of prizes, and as long as the rights to future prizes are tradable, granting of wide agency discretion has significant advantages and few drawbacks. Even assuming the agency is likely to do a poor job of distributing prizes, the system will be efficient if no biases in granting prizes are predictable. After addressing a variety of issues concerning the design of a prize system, Professor Abramowicz offers several potential applications for patent, copyright, an