685 research outputs found

    Performance Evaluation of Machine Learning Techniques for Identifying Forged and Phony Uniform Resource Locators (URLs)

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    Since the invention of Information and Communication Technology (ICT), there has been a great shift from the erstwhile traditional approach of handling information across the globe to the usage of this innovation. The application of this initiative cut across almost all areas of human endeavours. ICT is widely utilized in education and production sectors as well as in various financial institutions. It is of note that many people are using it genuinely to carry out their day to day activities while others are using it to perform nefarious activities at the detriment of other cyber users. According to several reports which are discussed in the introductory part of this work, millions of people have become victims of fake Uniform Resource Locators (URLs) sent to their mails by spammers. Financial institutions are not left out in the monumental loss recorded through this illicit act over the years. It is worth mentioning that, despite several approaches currently in place, none could confidently be confirmed to provide the best and reliable solution. According to several research findings reported in the literature, researchers have demonstrated how machine learning algorithms could be employed to verify and confirm compromised and fake URLs in the cyberspace. Inconsistencies have however been noticed in the researchers’ findings and also their corresponding results are not dependable based on the values obtained and conclusions drawn from them. Against this backdrop, the authors carried out a comparative analysis of three learning algorithms (Naïve Bayes, Decision Tree and Logistics Regression Model) for verification of compromised, suspicious and fake URLs and determine which is the best of all based on the metrics (F-Measure, Precision and Recall) used for evaluation. Based on the confusion metrics measurement, the result obtained shows that the Decision Tree (ID3) algorithm achieves the highest values for recall, precision and f-measure. It unarguably provides efficient and credible means of maximizing the detection of compromised and malicious URLs. Finally, for future work, authors are of the opinion that two or more supervised learning algorithms can be hybridized to form a single effective and more efficient algorithm for fake URLs verification.Keywords: Learning-algorithms, Forged-URL, Phoney-URL, performance-compariso

    Chemical Analysis and Short-term Toxicological Evaluation of Garcinia mangostana Seed Residue in Albino Rats

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    The short-term toxicological evaluation of defatted Garcinia mangostana seed residue in rat feed has been investigated in order to determine its suitability as an additive in feed supplement. Proximate analysis of the G. mangostana seed residue (GMSR) showed that it had a high carbohydrate and low protein values: 71.02±0.79 % and 8.09±0.21 % respectively. In vivo experiment with albino rats fed with feed that had its wheat constituent totally replaced by GMSR lasted for six weeks. The albino rats appeared to suffer no toxicological effect and weekly monitoring of the rats showed good physical appearance. The rats in the test group displayed fairly similar body weight gain when compared with those from the control group. There was no significant difference between the haematological and histopathological results obtained for both the experimental and control groups. GMSR seemed to be a good replacement for wheat in rat feed. Key words: Diet, Garcinia mangostana, proximate composition, total replacement, wheat

    Cloud Service Level Agreements –Issues and Development

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    Cloud computing is a broad paradigm that has influence across major fields of human endeavour. The unique services it offers makes organisations curious about understanding the cloud and its likely benefits. The cloud offers services such as custom built applications deployed on remote systems and ready to use platforms which reduce the efforts needed to develop and deploy applications for cloud users. In addition to these, there are other services such as storage and infrastructural resources which the cloud also avails to its users. These services are usually provided to users on a pay-per-use bases, thus necessitating the need to have documented agreements in place to ensure a smooth relationship between the providers and the users. These documented agreements are referred to as Service Level Agreements (SLAs). SLAs detail the terms, conditions and service expectation of the users from their service provider in terms of availability, redundancy, uptime, cost and penalties for violations. These ensures users’ confidence in the services being offered. In this paper, the state of the art with respect to cloud SLAs is presented. The paper seeks to answer questions related of what the current trends and developments in terms of cloud SLA are and it does so by means of a review of existing literature available. This paper therefore is a survey of cloud SLAs, their issues and developmental challenges. It provides a guide for future research and is expected to benefit prospective cloud users and cloud providers alik

    IMPLEMENTING AN ONLINE EXAMINATION SYSTEM

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    progressively enhanced the online examination process over the years. However, some schools particularly public tertiary institutions in developing countries are still involved in the conventional manual system of writing examination. This manual system of writing examination has a lot of demerits. The manual process of taking examinations is not only time-consuming and tedious, but cumbersome, hence the need for a better, faster and more reliable means of examining students. The objective of this paper is to provide a report on the implementation of a web-based examination system. The implemented system was modeled using Unified Modeling Language (UML) diagrams such as Use Case diagram, Sequence diagram and Activity diagrams. The system was developed using ASP.Net and Hypertext Markup Language (HTML), ASP.Net and C-sharp as front end, Internet Information Services (IIS) as middle ware and Microsoft SQL Server as database. With the online examination system, the process of conducting examinations and processing results is made ease. More so, there is a reasonable level of security and integrity on the conduct of examination

    Time-resolved energy transfer from single chloride terminated nanocrystals to graphene

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    We examine the time-resolved resonance energy transfer of excitons from single n-butyl amine-bound, chloride-terminated nanocrystals to two-dimensional graphene through time-correlated single photon counting. The radiative biexponential lifetime kinetics and blinking statistics of the individual surface-modified nanocrystal elucidate the non-radiative decay channels. Blinking modification as well as a 4 times reduction in spontaneous emission were observed with the short chloride and n-butylamine ligands, probing the energy transfer pathways for the development of graphene-nanocrystal nanophotonic devices

    Coronary artery dominance dependent collateral development in the human heart

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    Background: In obstructive coronary artery disease, coronary collateral arteries serve as alternative conduits for blood flow to the myocardial tissue supplied by the obstructed vessel(s). Therefore, they are a “natural coronary arterial bypass” to the region supplied by the obstructed vessels. This study aims to determine the influence of demographic and morphologic coronary arterial factors on coronary collateral development in coronary arterial obstruction. Materials and methods: The study group was selected from the coronary angiographic records of 2029 consecutive patients (mean age: 59 ± 12 years). Coronary collaterals were graded from 0 to 3 based on the collateral connection between the donor and recipient arteries. The angiograms of the patients (n = 286) with total obstruction of the coronary arteries were selected for analysis. Results: There were no significant association between patients’ age and sex and the formation of excellent collaterals. However, the location of atherosclerotic lesion affected collateral development in the right coronary artery. In addition, the right coronary arterial dominant pattern significantly influenced the formation of excellent coronary collaterals. Conclusions: Coronary collateral arteries are better developed in right dominant pattern. It may be concluded that coronary arterial morphological pattern influences coronary collateral artery development

    Short-Term Toxicological Evaluation of AnacardiumOccidentale Oil in Albino Rats

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    Anacardium occidentale L. nut oil was characterized after which 5% of it was incorporated in the feed formulation for albino rats. Two diets were formulated; one of these diets had 5 % A. occidentale oil (test diet) while the other had 5% of groundnut oil as a representative of conventional edible oil (control diet).  Proximate analysis result indicated that the nut comprises of 5.82 ± 0.16% moisture, 25.54 ± 0.25% protein, 6.28 ± 0.02% crude fibre, 42.52 ± 0.45% fat, 2.90 ± 0.09% ash and 16.97 ± 0.84% carbohydrate.  A. occidentale nut was found to be rich in potassium and magnesium.  Physicochemical analysis of cashew nut oil gave 22.03 ± 0.04 mgKOH/g acid value, 22.03 ± 0.40 g/100g iodine value, 1.96 ± 0.23 mgKOH/g free fatty acid, 97.98 ± 0.99 mgKOH/g saponification value, 2.96 ± 0.59 peroxide value and 1.64 ± 0.02 refractive index.  Fatty acid analysis of A. occidentale nut oil showed that it has high level of unsaturation (77.5754%).  This is evident from the values obtained for oleic acid (61.02%), linoleic acid (15.34%) and linolenic acid (0.13%). There was weight gain by the rats during the feeding period of eight weeks and no mortality was recorded. Haematological and biochemical parameters were investigated for in the test and control rats and the results obtained revealed no adverse effect on the rats’ blood.  The cholesterol level in the test and control rat tissues was not significantly different at p<0.05.  The result of the histopathology of some of  the rat tissues showed no visible lesion.  A. occidentale nut oil might be suitable for edible purposes. Key words:A. occidentale, fatty acid, proximate composition, toxicolog

    The prevalence and clinical importance of an “additional” terminal branch of the left coronary artery

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    The left coronary artery (LCA) usually divides into two (anterior interventricular artery [AIA] and left circumflex [LCx] artery) or less frequently into the AIA, LCx, and one or more “additional” terminal branch/es (ATBs). These ATBs of the LCA have no unanimity regarding their anatomical nomenclature. There is a lack of common consensus on the criteria used for their definition, and they are also absent from the current Terminologia Anatomica (1998). This study, therefore, aimed to document the prevalence of the ATBs of the LCA, discuss their clinical importance, and propose an anatomical nomenclature. This study was conducted by reviewing 367 coronary angiograms. The termination patterns of the LCA were classified into 3 categories based on the number of their branches, viz. (a) bifurcation 78.2%, (b) trifurcation 20.4%, and (c) quadrifurcation 1.4%, respectively. The presence of an ATB was recorded in 21.8% of the angiograms. The identification of this vessel may be of clinical importance because the extent of its supply may decrease the effect of occlusion of the LCx artery and AIA on the myocardium. The term “left ramus medianus artery” is proposed as the nomenclature for the ATB of the LCA

    Construction and Testing of a Treatment System for Raw Water

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    Water is a wonder of Nature. One among the major problems confronting the world today is access to clean and safe water. The objective of the study was to assemble an affordable water treatment unit for domestic use. This study was carried out in Auchi, which is located between latitude 70 10’ and 70 20’ North of the equator and longitude 60 16’ and 60 36’ east of the Greenwich Meridian with an altitude of 207m. The components of the treatment system are raw water tank, coagulation tank, sedimentation tank, filtration chamber, micro filters, ultraviolent light and treated water storage tank. Sample of the raw water collected from River Orhle in Auchi was kept at a constant temperature in a refrigerator. The raw and  treated water sample was collected in a four litres jerican for laboratory analysis to test for Turbidity, pH, Appearance, Taste, Colour, Electrical conductivity, total dissolved solid (TDS), Nitrates, iron content, total hardness etc. The results met the desired specifications and standards set by WHO and NAFDAC for potable water usage. Keywords: Potable water, raw water, water treatment, slow sand filter, ultraviolent light, water qualit
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