14 research outputs found

    A forensic acquisition and analysis system for IaaS

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    Cloud computing is a promising next-generation computing paradigm that offers significant economic benefits to both commercial and public entities. Furthermore, cloud computing provides accessibility, simplicity, and portability for its customers. Due to the unique combination of characteristics that cloud computing introduces (including on-demand self-service, broad network access, resource pooling, rapid elasticity, and measured service), digital investigations face various technical, legal, and organizational challenges to keep up with current developments in the field of cloud computing. There are a wide variety of issues that need to be resolved in order to perform a proper digital investigation in the cloud environment. This paper examines the challenges in cloud forensics that are identified in the current research literature, alongside exploring the existing proposals and technical solutions addressed in the respective research. The open problems that need further effort are highlighted. As a result of the analysis of literature, it is found that it would be difficult, if not impossible, to perform an investigation and discovery in the cloud environment without relying on cloud service providers (CSPs). Therefore, dependence on the CSPs is ranked as the greatest challenge when investigators need to acquire evidence in a timely yet forensically sound manner from cloud systems. Thus, a fully independent model requires no intervention or cooperation from the cloud provider is proposed. This model provides a different approach to a forensic acquisition and analysis system (FAAS) in an Infrastructure as a Service model. FAAS seeks to provide a richer and more complete set of admissible evidences than what current CSPs provide, with no requirement for CSP involvement or modification to the CSP’s underlying architecture

    Space Vector Modulation Technique to Reduce Leakage Current of a Transformerless Three-Phase Four-Leg Photovoltaic System

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    Photovoltaic systems integrated to the grid have received considerable attention around the world. They can be connected to the electrical grid via galvanic isolation (transformer) or without it (transformerless). Despite making galvanic isolation, low frequency transformer increases size, cost and losses. On the other hand, transformerless PV systems increase the leakage current (common-mode current, (CMC)) through the parasitic capacitors of the PV array. Inverter topology and switching technique are the most important parameters the leakage current depends on. As there is no need to extra hardware for switching scheme modification, it's an economical method for reducing leakage current. This paper evaluates the effect of different space vector modulation techniques on leakage current for a two-level three-phase four-leg inverter used in PV system. It proposes an efficient space vector modulation method which decreases the leakage current to below the quantity specified in VDE-0126-1-1 standard. furthermore, some other characteristics of the space vector modulation schemes that have not been significantly discussed for four-leg inverter, are considered, such as, modulation index, switching actions per period, common-mode voltage (CMV), and total harmonic distortion (THD). An extend software simulation using MATLAB/Simulink is performed to verify the effectiveness of the modulation technique

    Analysis of DNA ploidy and expression of tumour-associated antigens on human oral carcinomas xenografted in nude mice

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    Human squamous cell carcinomas (SCC) of the oral cavity were successfully established as xenografts in nude mice. Tumours with higher malignancy scores and involvement of lymph nodes in patients were more readily accepted as xenografts in nude mice. The xenografted tumours were characterised with respect to morphology, histology, DNA index and expression of tumour-associated antigens (TAA). Flow cytometric analysis of cellular DNA content revealed that many of the xenografts retained the parent tumour DNA pattern while some of the xenografts showed progression to aneuploidy. All the xenografted tumours expressed TAA recognised by monoclonal antibody (MAb) 3F8E3. On Western blotting, MAb 3F8E3 recognised proteins of molecular weight 62-64 kDa on parent and xenografted tumours. In general, the xenografts reflect many of the characteristics of the tumours from which they were derived and may provide a useful model for investigating newer approaches of treatment and diagnosis

    Experts reviews of a cloud forensic readiness framework for organizations

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    Cloud computing has drastically altered the ways in which it is possible to deliver information technologies (ITs) to consumers as a service. In addition, the concept has given rise to multiple benefits for consumers and organizations. However, such a fast surge in the adoption of cloud computing has led to the emergence of the cloud as a new cybercrime environment, thus giving rise to fresh legal, technical and organizational challenges. In addition to the vast number of attacks that have had an impact on cloud computing and the fact that cloud-based data processing is carried out in a decentralized manner, many other concerns have been noted. Among these concerns are how to conduct a thorough digital investigation in cloud environments and how to be prepared to gather data ahead of time before the occurrence of an incident; indeed, this kind of preparation would reduce the amount of money, time and effort that is expended. As a number of cloud forensics challenges have not received enough attention, this study is motivated by a particular gap in research on the technical, legal and organizational factors that facilitate forensic readiness in organizations that utilize an Infrastructure as a Service (IaaS) model. This paper presents a framework with which to investigate the factors that facilitate the forensic readiness of organizations. This framework was identified by critically reviewing previous studies in the literature and by performing an in-depth examination of the relevant industrial standards. The factors were comprehensively studied and extracted from the literature; then, the factors were analysed, duplicates were removed, and the factors were categorized and synthesized to produce the framework. To obtain reliable results, the research method involved two steps: a literature review, followed by expert reviews. These techniques help us paint a comprehensive picture of the research topic and validate and confirm the results.Northern Border Universit

    Physiological and performance effects of glycerol hyperhydration and rehydration

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    Studies have shown that beverages containing glycerol can enhance and maintain hydration status and may improve endurance exercise performance by attenuating adverse physiological changes associated with dehydration. Improvements to performance include increased endurance time to exhaustion by up to 24%, or a 5% increase in power or work. However, some studies have found no performance benefits during either prolonged exercise or specific skill and agility tests. In studies that have shown benefits, the improvements have been associated with thermoregulatory and cardiovascular changes. These include increased plasma volume and sweat rates, as well as reduced core temperature and ratings of perceived exertion. In a very small number of subjects, glycerol consumption has been associated with side-effects including nausea, gastrointestinal discomfort, dizziness, and headaches. In summary, while glycerol and fluid ingestion results in hyperhydration, the documented benefits to exercise performance remain inconsistent
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