Lead-acid batteries have been used increasingly in recent years in solar power systems, especially in homes and small businesses, due to their cheapness and advanced development in manufacturing them. However, these batteries have low voltages and low capacities, to increase voltage and capacities, they need to be connected in series and parallel. Whether they are connected in series or parallel, their voltages and capacities must be equal otherwise the quality of service will be degraded. The fact that these different voltages are inherent in their manufacturing, but these unbalanced voltages can be controlled. Using a switched capacitor is a method that was used in many methods for balancing voltages, but their responses are slow. To increase the response and control of the balancing process, this research proposes a novel technique that consists of a dynamic capacitor for controlling the unbalanced voltages of series-connected lead-acid batteries. The proposed technique uses a main capacitor and an inductor with two switches their on/off states are controlled through a pulse width modulation. The technique is designed and validated using MATLAB/Simulink and the results for different cases are compared with other techniques such as switched capacitor technique. Results show that the proposed method promised the balancing control in a shorter time and better performance than other techniques which are crucial in the battery’s voltage balancing.
Compaction curves are widely used in civil engineering especially for road constructions, embankments, etc. Obtaining the precise amount of Optimum Moisture Content (OMC) that gives the Maximum Dry Unit weight gdmax. is very important, where the desired soil strength can be achieved in addition to economic aspects.
In this paper, three peak functions were used to obtain the OMC and gdmax. through curve fitting for the values obtained from Standard Proctor Test. Another surface fitting was also used to model the Ohio’s compaction curves that represent the very large variation of compacted soil types.
The results showed very good correlation between the values obtained from some publ
... Show MoreMany changes took place in a number of Arab countries, most of which ended with the change of the ruling leadership and a new coming. The same change brought about the hopes of the people to turn the page of the past into a democracy through which to overcome the grievances of previous years and achieve justice in all its aspects. The same new grievances have been added to that precedent and justice has not yet been achieved. Here we try to address the justice that is applied in the stages of change or transitional stages, which have been called, ie transitional justice, which has mechanisms and conditions of different application between countries, each of which the conditions applied in them and through a review of these mechanisms bet
... Show MoreThe goal of current research is to identify the difficulties in the application of modern physics in the middle schools of the province of Baghdad schools from the perspective of teachers of physics trends, sample search of (127) teachers, Karkh Third Directorate, and use Researcher questionnaire data collection tool after applying it to teachers who have experience (5) years and more after confirmation of the validity and reliability of the scale (the tool) researcher has used the averages for the purpose of interpreting the results. the results showed that the difficulties have been in the order following: (difficulties related educational environment of modern trends of teaching, curriculum-related dif
... Show MoreAgricultural nozzles usually produce a different drops size depending on the pressure and the physical condition (work life) of the nozzle besides producing a wide range of the drops spectrum in the spray cloud. In this paper the standard flat fan nozzles were investigated regarding the effect of the working pressure and the nozzle physical condition (new and worn nozzles). The size of drops and the spectrum of drops across the long axis of the spray pattern were examined by using Sympatec GmbH Laser Diffraction. Reducing the working pressure from 3 to 2 and then to 1 caused production of larger drops, also using worn nozzles (especially with lower pressure) changed the drops size whi
ABCTRACT
Care research examining the relationship between the variables of search presidents (employee training and organizational commitment) to determine the effect of the training of employees in organizations in achieving organizational commitment of employees towards their organizations and by the fact that training is one of the most important activities adopted by the administration and by which can benefit realized for workers and for the organization .ttjsd problem Search lack of training considered as a factor of the important factors in the development of staff skills and development work in many Iraqi companies, including vegetable oils company (where to look), which in turn raises the relevance and commitment
... Show MoreThe construction sector consumes large amounts of energy during the lifetime of a building. This consumption starts with manufacturing and transferring building materials to the sites and demolishing this building after a long time of occupying it. The topic of energy conservation and finding the solution inside the building spaces become an important and urgent necessity. It is known that the roof is exposed to a high amount of thermal loads compared to other elements in a building envelope, so this needs some solutions and treatments to control the flow of the heat through them. These solutions and treatments may be achieved by using nanomaterials. Recently, nanomaterials have high properties, so that this made them go
... Show MoreThe study aims to identify the extent the academics in colleges of applied sciences are familiar with the themes of the national strategy of education 2040 in the Sultanate of Oman. The researchers used the descriptive approach, as well as they adopted a questionnaire with five dimensions as a tool for data collection, which was applied to (120) academics. The results showed that the academics of the applied colleges' familiarity with the National Strategy for Education 2040 in the Sultanate of Oman is average. The study also found that there were no statistically significant differences in the academics estimates of the extent of the Colleges of Applied Sciences academics’ familiarity with the themes of the National Education 2040 Str
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The public budget in Iraq is still prepared according to the traditional base that allocates the amounts of budget the current year based on the budget of previous year with an increase in estimations with random proportions without connecting the input (financial, human resources and asset )with their output (quantitatively and qualitatively)this caused waste and lose in the available resources therefore the output of budget showed be adapted is such a way that achieving connection between its input and output and to be appropriate with the organizational structure of the state without intrinsic change in its work .this may be realized by adopting the accounting of
... Show MoreThe use of data envelopment analysis method helps to improve the performance of organizations in order to exploit their resources efficiently in order to improve the service quality. represented study a problem in need of the Iraqi Middle East Investment Bank to assess the performance of bank branches, according to the service quality provided, Thus, the importance of the study is to contribute using a scientific and systematic method by applying the data envelopment analysis method in assessing the service quality provided by the bank branches, The study focused on achieving the goal of determining the efficiency of the services quality provided by the bank branches manner which reflect the extent of utilization of a
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