Browsing by Author "Ateş A.M."
Now showing 1 - 5 of 5
Results Per Page
Sort Options
Item Perceptions of students and teachers participating in a science festival regarding science and scientists(Routledge, 2021) Ateş Ö.; Ateş A.M.; Aladağ Y.Background: Numerous studies have been conducted to identify students’ perceptions of science and scientists since the 1950s. Those studies have revealed that students have stereotypical perceptions, on which teachers may have a significant effect. It is, therefore, essential to determine both teachers’ and students’ perceptions. Purpose: The aim of this study is to investigate students’ and teachers’ perceptions of science and scientists. Sample: The sample for the study consisted of 85 students and 47 teachers who participated in a science festival. Design and methods: The study is based on a descriptive survey model. Data were collected using the Draw-A-Scientist Test (DAST) and Word Association Test (WAT), and analyzed using content analysis. Results: Participants’ drawings focused on scientists’ physical characteristics, type of activity, working environment and the materials used while conducting experiments. A scientist was often depicted as a man in a lab coat with strange hair and eyeglasses and using laboratory materials. Teachers made more detailed drawings of scientists’ working style and environment and more detailed associations with the nature of science, ways of acquiring scientific knowledge and scientific process. Unlike teachers, students emphasized space-related concepts both in their drawings and word associations. Conclusion: This study shows that both teachers and students possess various stereotypical perceptions of scientists aligned with the previous studies. However, the number of scientists drawn as happy and female is higher than the previous studies, which is a promising finding. Moreover, students’ drawings consisting symbols or alternative images that evoked space in particular is one of the several aspects which differentiate this study from most studies. This study also shows that using drawings and word association tests together provides a richer understanding of people’s views of science and scientists than using only one measurement tool. © 2020 Informa UK Limited, trading as Taylor & Francis Group.Item Unlocking the floating photovoltaic potential of Türkiye's hydroelectric power plants(Elsevier Ltd, 2022) Ateş A.M.The massive surface of the water accumulated in the basins of hydroelectric power plants (HEPPs) can be considered an excellent opportunity for floating photovoltaics (FPV). Türkiye is among the countries that can utilize this potential with its large HEPPs. In this study, the surface areas of 76 HEPPs in Türkiye were determined using the Random Forest algorithm over Google Earth Engine, and the technical potential of FPV that could be installed in these areas was evaluated over five scenarios. In addition, the water recovery that can be obtained with the FPV installation has been calculated. When the entire surfaces of the dams are used, the FPV technical potential and the amount of water recovered are 380,439.85 MW and 25.40 km3/year, respectively. Even when only 10% of the surfaces of the dams are used, the FPV technical potential meets 39.67% of Türkiye's total installed power capacity. Moreover, the water recovered from evaporation meets 7.3% of the surface water used for agricultural irrigation. In addition, it has been calculated that the FPV electricity generation potential of HEPPs producing 674,280.17 GWh of electricity in 2020 is 13.82 times higher than the hydroelectric potential. The results demonstrated how great the FPV solar power plant potential that the country HEPPs carries on their idle water surfaces. © 2022 Elsevier LtdItem A novel approach suggestion for assessing the impact of topographic shading on the estimation of the floating photovoltaic technical potential(Elsevier Ltd, 2023) Yilmaz O.S.; Ateş A.M.; Gülgen F.This study presents a novel approach for the implementation of floating photovoltaic (FPV) systems at the Ayvalı hydroelectric power plant (HPP) in Türkiye. The method proposed in this study accounts for dynamic changes in water levels to accurately calculate the shading effects induced by topography. First, the minimum reservoir surface for the FPV system was calculated using remote sensing (RS). The minimum reservoir surface area, which was determined as 504.69 ha using 60 Sentinel-2 satellite images, was calculated using machine learning algorithms on the Google Earth Engine (GEE) platform, support vector machines (SVM) and automatic water extraction index (AWEI). In the second stage, new digital elevation model (DEM) maps were produced by overlapping monthly changes in water height with ALOS PALSAR data and solar analysis was performed on them. An annual global horizontal irradiance (GHI) map was produced using these maps, and it was divided into five classes to emphasize differences in production potential. The results revealed that 1083.45 GWh of electricity can be produced annually by installing FPV in very high and high potential areas. However, as the moderate, low, and very low regions represent only 5.02% of the reservoir surface and there is a 1.68-fold difference in production potential between the highest and lowest areas due to topography-induced shading near the coastline, it was concluded that FPV installation would not be efficient in those regions. This study highlights the significance of incorporating topography-induced shading and emphasizes the importance of employing RS and geographic information system (GIS) techniques to achieve this objective. © 2023Item Determination of the appropriate zone on dam surface for floating photovoltaic system installation using RS and GISc technologies(Murat Yakar, 2023) Yılmaz O.S.; Gülgen F.; Ateş A.M.This study aims to reveal suitable places where floating photovoltaic-solar power plants (FPV-SPPs) can be installed on the dam surface using the possibilities of remote sensing (RS) and geographical information science (GISc) technologies. Past satellite images from Landsat and Sentinel platforms allow researchers to analyse shoreline changes in the dam surface. Shoreline extraction is a crucial process for the FPV-SPP to stay afloat despite external constraints. In this study, changes in dam water levels were determined by classifying 20-year satellite images and analysing a 32-year global surface water dynamics dataset. The water surface area was calculated as 1,562.40 ha using the random forest (RF) algorithm and the normalized differences water index (NDWI) on Google Earth Engine (GEE) cloud platform. In addition, solar analysis was carried out with GISc using annual solar radiation maps shuttle radar topography mission (SRTM) data, which directly affects the energy production of FPV-SPPs. It has been calculated that the solar radiation on the water surface varies between 1,554 kWh/m2-year and 1,875 kWh/m2-year. These calculated values were divided into five different classes, and it was observed that 88.5% of the dam surface had a very high level of solar radiation compared to other areas. Higher efficiency will be obtained from the FPV-SPP to be installed in this region compared to the systems to be installed in other regions. It has been observed that the radiation values in other parts of the water surface are lower due to topographic shading. These analyses revealed energy zones with high production potential, thereby easing the decision-making process for investors planning to establish FPV-SPPs. © Author(s) 2023.Item Investigation of Water Quality in Izmir Bay With Remote Sensing Techniques Using NDCI on Google Earth Engine Platform(John Wiley and Sons Inc, 2025) Yılmaz O.S.; Acar U.; Sanli F.B.; Gülgen F.; Ateş A.M.In this study, the effects of algal blooms occurring in Izmir Bay in the summer of 2024 on marine ecosystems were investigated using remote sensing techniques on Google Earth Engine platform. The normalized difference chlorophyll index (NDCI) was calculated from January to the end of September and the chlorophyll-a density was analyzed. Additionally, an NDCI time series analysis was conducted between September 2018 and 2024 at the designated points. The values, which fluctuated narrowly until 2022, showed a sharp increase in 2024. NDCI, which vary between −0.4 and 0.2 in January 2024 and increase up to 0.8 toward the summer months, indicate that algal blooms are occurring, concentrated in critical areas such as Karşıyaka, Bayraklı, and Alsancak Port. These findings revealed a connection between the sudden fish deaths in the bay during the summer of 2024 and algal blooms, as well as the deterioration of water quality. © 2025 The Author(s). Transactions in GIS published by John Wiley & Sons Ltd.