6 research outputs found

    Optimal Placement of Phasor Measurement Units for Power Systems Using Genetic Algorithm

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    Power grids require monitoring to operate with high efficiency while minimizing the chances of having a failure. However, current monitoring scheme which consists of SCADA (Supervisory Control and Data Acquisition), accompanied with conventional meters distributed throughout the grid, is no longer sufficient to maintain an acceptable operation of the grid. This is evident from the multiple failures and blackouts that happened and are still happening in grids worldwide. This issue became more severe due to systems being operated near their limits (to reduce costs and due to the increase in electricity demands), as well as, the addition of renewable energy sources, which usually have abrupt changes. Smart grids were introduced as a solution to this issue by the inclusion of Wide Area Monitoring System (WAMS), which is mainly based on Phasor Measurement Units (PMU), which are measurement devices that provides synchronized time stamped measurements with high sending rate which significantly improves the monitoring of the grid. However, PMUs are relatively expensive (considering both direct and indirect costs incurred). Thus, it is desired to know the minimum number of PMUs required for achieving certain monitoring criteria. Thus, Optimal PMU Placement (OPP) formulates an optimization problem to solve this issue. In the literature of OPP, multiple objectives and constraints are considered, based on desired criteria. In this thesis, a review of OPP is made, followed by the application of selected algorithms (Integer Linear Programming and Genetic Algorithm) on various test systems as a verification and then applying it to Qatar Grid, to compare between different considerations as well as gain insight about the possible PMU placements for Qatar Grid. The contribution of this thesis is introducing a modified fitness function for the Genetic Algorithm that provides more diverse results than previous papers, while incorporating for various considerations like Zero Injection Buses, Conventional Measurements and current branch limit. It also analyzes the results of current branch limit and provides new plots describing their effects

    A Cross-sectional Study on Hepatitis B Immune Status among Vaccinated Healthcare Workers in Khartoum, Sudan

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    Background: Hepatitis B virus (HBV) infection can lead to chronic hepatitis, liver cirrhosis, and Hepatocellular Carcinoma (HCC). Vaccination against the virus plays an important role in its prevention. Health personnel at risk of infection are recommended to receive the vaccine and to check their immune status thereafterObjective:   To determine Hepatitis B Immune status among vaccinated health personnel in Khartoum state, Sudan.A total of 106 health personnel from different hospitals and doctors’mess in Khartoum and from different jobs were surveyed and their HBV surface antibodies levels were determined by HBsAb (Quantitative) ELISA Kits.Methods: Of the 106 participants in this study, the majority were females 72.6%. The mean age of those involved was 27.69 years, and nurses made for more than 50% of those surveyed. About 56.6% (60) of the health personnel involved took three or more doses of HBV vaccine while the rest received one or two doses. The results of the participants who received three or more doses of the vaccine represented immunity by 70%. In general, about 47.2% (50) of the participants in this study did show excellent immune response (> 100 mIU/mL) and 18.9% (20) had weak protective levels (between 10 and 100 mIU/mL)So, we concluded that HBV post-vaccination immunity status of health personnel in Khartoum state is lower than post-vaccination HBV immunity in other parts of the world. There is an urgent need for a national protocol of HBV vaccination to improve the immunization status of health personnel with a regular checkup of HBV immunity and easy access to a good-quality vaccine. Keywords: hepatitis B vaccines; healthcare workers; immune respons

    Full Length Review Article EFFICACY OF KINESIO TAPING VERSUS PHONOPHORESIS ON MECHANICAL NECK DYSFUNCTION

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    ABSTRACT Background: Mechanical Neck Dysfunction (MND) affects about two thirds of people in middle age with common cause of bad posture in people who spent much of their working day at a desk with a bent-forward posture. Purpose: To compare the efficacy of kinesio taping versus phonphoresis on neck pain intensity, cervical ROM and neck disability in patients with MND

    Integrated multiomics analysis to infer COVID-19 biological insights

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    Abstract Three years after the pandemic, we still have an imprecise comprehension of the pathogen landscape and we are left with an urgent need for early detection methods and effective therapy for severe COVID-19 patients. The implications of infection go beyond pulmonary damage since the virus hijacks the host's cellular machinery and consumes its resources. Here, we profiled the plasma proteome and metabolome of a cohort of 57 control and severe COVID-19 cases using high-resolution mass spectrometry. We analyzed their proteome and metabolome profiles with multiple depths and methodologies as conventional single omics analysis and other multi-omics integrative methods to obtain the most comprehensive method that portrays an in-depth molecular landscape of the disease. Our findings revealed that integrating the knowledge-based and statistical-based techniques (knowledge-statistical network) outperformed other methods not only on the pathway detection level but even on the number of features detected within pathways. The versatile usage of this approach could provide us with a better understanding of the molecular mechanisms behind any biological system and provide multi-dimensional therapeutic solutions by simultaneously targeting more than one pathogenic factor
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