<p>Photovoltaic (PV) systems are becoming increasingly popular; however, arc faults on the direct current (DC) side are becoming more widespread as a result of the effects of aging as well as the trend toward higher DC voltage levels, posing severe risk to human safety and system stability. The parallel arc faults present higher level of current as compared with the series arc faults, making it more difficult to spot the series arc. In this paper and for the aim of condition monitoring, the features of a DC series arc fault are analyzed by analysing the arc features, performing model’s simulation in PSCAD, and carrying out experimental studies. Various arc models are simulated and investigated; for low current arcs, the heuristic model is used where a set of parameters established. Moreover, the heuristic model’s simulated arc has been shown to be compatible with the experimental data. The features of arc noise in the electrode separation region and steady-arcing states with varied gap widths are investigated. It has been discovered that after an arc fault occurs, arc noise increases, notably in the frequency range below 50 kHz; where this property is useful for detecting DC series arc faults. Besides that, variations in air gap width are more sensitive to frequencies under 5 kHz.</p>
The Evolution Of Information Technology And The Use Of Computer Systems Led To Increase Attention To The Use Of Modern Techniques In The Auditing Process , As It Will Overcome Some Of The Human Shortcomings In The Exercise Of Professional Judgment, Then It Can Improve The Efficiency And Effectiveness Of The Audit Process, Where The New Audit Methodologies Espouse The Concept Of Risk Which Includes Strategic Dimension With Regard To The Capacity Of The Entity To Achieve Its Goals, Which Requires Auditors To Rely On Advanced Technology That Can Identify The Factors Which Prevent The Entity From Achieving Its Objectives. The Idea Of Research Is To Preparing An Electronic Program Fer All Audit Work From Planning Through Sampling And Document
... Show MoreThe increase of the scenographic designer role on account of the character of the director in the Iraqi theater constituted a clear phenomenon that has been manifested in many shows, which necessitated a stance on the nature of this relation and delimiting the work space for each one of them inside the theater show. The research focuses on determining the work relation between the directorial vision and the scenographic proposal in the Iraq theater show. The research is divided into four chapters, the first one addressed the methodological framework, where the research problem was stated in the following question (has the scenographic designer been able through his scenographic proposal to remove the director from his position being the
... Show Moreهدف البحث الى بيان طبيعة ارتباط والتأثير بين الضغوط التنافسية (المتغير المستقل) والتجديد الاستراتيجي (المتغير التابع) ، تم تطبيق البحث في فنادق الدرجة الممتازة في بغداد. وبلغت عدد افراد عينة البحث (99) مديراً يعملون في (6) فنادق من الدرجة (الممتازة) ببغداد، وهي (فندق الرشيد، فندق عشتار، فندق ميريديان، فندق المنصور، فندق بابل، وفندق بغداد) وتم اجراء التحليل الاحصائي باستخدام البرنامج الاحصائي AMOS وظهرت وجود تنافسي
... Show MoreExogenous levothyroxine dose modulation and euthyroidism achievement is a persistent challenge in clinical settings. This study strives to assess the adequacy of treatment and identify the patients’ factors that can be used to estimate the euthyroid levothyroxine dose. A secondary objective was to assess vitamin D supplementation impact on thyroid status.
A review of a prospectively collected information from 142 female patients from Baghdad Center of Nuclear Medicine from June 2019 until March 2020 who were receiving levothyroxine for different causes was done. After a follow-up period, the patients’ thyroid tests were assessed and the euthyroid doses for each cause category were statistically analyzed. Thyroid function was
... Show MoreThe five-a- Side Soccer for simple mental disability is as interesting and caring as many other sporting events. Therefore, the researchers believe that their basic skills tests are compatible with then level of the tested individuals in terms of age and mental ability. As a means of selecting those who are qualified to practice this game in a simple way, the problem of research has been identified in the design and standardization of two scoring skills that belong to this category and are approved by the training staff during the initial selection process. The research community is determined by people with mental disabilities who belong to the governmental and private institutes and the Special Olympics Union in Baghdad and for the year 2
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The critical success factors of the means of the most modern in determining the main directions for organizations to achieve competitive advantage. and can be a critical success factors in organizations that overlap in the functional areas of the organization. that successful organizations use these factors to get to the uniqueness and distinction. as the entrance of critical success factors with the capacity Evaluative phase correction because discovery increases the perception of managers of what is important to the organization and using them to get to the Strategic Entrepreneurship. as it begins in terms of permanence of success and
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