Yazar "Kaya, Huseyin" seçeneğine göre listele

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    Experimental performance investigation of high reflective and diffuse reflective concentrating photovoltaic/ thermal (CPVT) systems using non-imaging concentrators from energy, exergy, and economic viewpoint
    (Pergamon-Elsevier Science Ltd, 2025) Ustaoglu, Abid; Buyukpatpat, Hakan; Kaya, Huseyin; Kursuncu, Bilal; Karaagac, Mehmet Onur; Okajima, Junnosuke
    A diffuse reflective (DR) surface in a concentrating photovoltaic thermal system (CPVT) system can provide uniform solar energy dispersion, minimizing hot spots, uneven lighting, and efficiency loss compared to costlier, highly reflective (HR) surfaces. This study uniquely compares the performance of HR-CPVT and DR-CPVT systems, highlighting the significant thermal and electrical efficiency of HR-CPVT while demonstrating the cost-effectiveness of DR-CPVT. The direct comparison of these systems under varying conditions provides novel insights into the trade-offs between high performance and economic feasibility. The performances of CPVTs were examined under various seasonal and weather conditions. The advantage of HR-CPVT was less pronounced in autumn due to seasonal effects. In the summer season, the cooling effect of water becomes more prominent, and the HR-CPVT outperformed the DR-CPVT by 6.1 to 8.5 %, depending on the mass flow rate in terms of overall efficiency. This advancement majorly arises from thermal efficiency. HR-CPVT achieved about a 5.6-7.9 % larger thermal efficiency. However, the electrical efficiency difference was minimal (similar to 0.5 %) and diminished to 0.1 % in the afternoon due to practical PV power generation limits. Despite its high reflectivity, HR-CPVT showed only marginal exergetic benefits over DR-CPVT. The simple payback period was calculated to be 3.65 years for HRCPVT, while it was only 3.19 years for DR-CPVT due to its lower installment cost. RSM analysis accurately predicts the experimental results.
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    Öğe
    The Use of Google Earth Images and QGIS Open-Source Software in Social Studies Education
    (Marmara Univ, 2015) Ayas, Cemalettin; Kaya, Huseyin; Tastan, Bekir; Ozder, Adem
    In this study, map and scale issues in Life on Earth unit of the People, Places and Environments learning area covered in the Middle School 6th Grade Social Studies have been addressed. While skills to be addressed directly on this topic are map reading and atlas use; the major value wished to be gained by the students is the sensitivity to the natural environmental. The present study aimed at developing an exemplary application for the social studies lessons on map-scale issues by the use of Google Earth images and an open-source GIS software, QGIS. The main objective here is to enable students construct a map of the place in which they live by the help of Google Earth images and open-source GIS software. For the activity, students first download the maps of where they live from the Google Earth application; and then they carry out a number of tasks to create their own maps with all the aspects such as length, direction and so in order to develop their skills on map reading. In this present study, by doing such an exemplary lesson activity, students create maps of where they live; that is, they integrate technology into their learning environment as well as they exercise active learning principles which help them grasp the knowledge, skills and values better.