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        Techno-economic assessment of a hybrid connected PV solar system

        Falih Hasan,Hamed Ahmed J.,Khalifa Abdul Hadi N. 대한설비공학회 2022 International Journal of Air-Conditioning and Refr Vol.30 No.1

        The current work was performed a techno-economic analysis of a 5-kWp capacity hybrid-connected solar system installed on the roof of a house at Diyala province, Iraq (33.77° N, 45.14° E, elevation 44 m). The rooftop PV solar system consists of 18 polycrystalline PV modules of 355 W each, an energy storage system consisting of 8 batteries of 150 Ah, 12 V, and an intelligent inverter of 5-kWp capacity. The PV string output energy and the load sharing between the PV output, the grid, and the discharging energy from the energy storage system are studied. While the economic assessment of the PV system is performed by calculating the net present value (NPV) depending on the discount cash flow method, from the results, the payback time is found. The PV system’s annual results showed that the PV system’s energy yield is 8.9 GWh/year, and the array efficiency, performance ratio, and load efficiency were 0.126, 0.66, and 0.92, respectively. The reference, array, and final yields were 6.1, 3.88, and 3.99 h/day, respectively. The minimum energy feed to the grid was in summer, and the maximum was in winter. On the other hand, the results showed that the maximum purchasing energy was in summer, and the less was in winter. The economic assessment showed that the minimum tariff for Iraq should not be less than 0.1 $/kWh with a PB time equal to PV lifetime; a tariff of 0.12 $/kWh is profitably for Iraq, as the PB time is 10 years.

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        Relational Data Extraction and Transformation: A Study to Enhance Information Systems Performance

        Forat Falih Hasan,Muhamad Shahbani Abu Bakar 한국정보통신학회 2022 Journal of information and communication convergen Vol.20 No.4

        The most effective method to improve information system capabilities is to enable instant access to several relational database sources and transform data with a logical structure into multiple target relational databases. There are numerous data transformation tools available; however, they typically contain fixed procedures that cannot be changed by the user, making it impossible to fulfill the near-real-time data transformation requirements. Furthermore, some tools cannot build object references or alter attribute constraints. There are various situations in which tool changes in data type cause conflicts and difficulties with data quality while transforming between the two systems. The R-programming language was extensively used throughout this study, and several different relational database structures were utilized to complete the proposed study. Experiments showed that the developed study can improve the performance of information systems by interacting with and exchanging data with various relational databases. The study addresses data quality issues, particularly the completeness and integrity dimensions of the data transformation processes.

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