Climate change has increased the importance in recent years. With the help of the developed scena... more Climate change has increased the importance in recent years. With the help of the developed scenarios, by predicting the future climate, it is aimed to eliminate the negative effects of climate change. In this study, the effectiveness of the reference data used to evaluate the future forecasts of climate change in temperature and precipitation parameters has been examined. Observed data of 11 Meteorology Stations (MS) located at different locations in the Eastern Black Sea Basin, which was determined as the research region, and precipitation and temperature projection data, obtained from GFDL-ESM2M, HadGEM2-ES and MPI-ESM-MR Global Circulation Model(GCM), have been used. In the study, by taking the data between 1971-2000 years, obtained by running the GCMs backwards, and the observed data in the same years as a reference, the precipitation and temperature changes for the periods between 2022-2040(P1), 2041-2070(P2) and 2071-2099(P3) average anomalies have been evaluated. As a result, it has been determined that the differences in the reference data selection, projection data and observed data, have an effect on the anomaly calculations. It has been concluded that the selection of reference data in regions with high natural relief is of critical importance for the performance of the climate analyzes.
In this study, by using 5 different input models, point rainfall-runoff model has been generated ... more In this study, by using 5 different input models, point rainfall-runoff model has been generated by means of different Artificial Neural Network (ANN) structures. The daily average discharge data of D22A116 Flow Gauging Station, located in Giresun Province Aksu Stream, together with daily average rainfall data measured at Giresun Meteorology Station 17034 were used in the study. In the generated rainfall-runoff model; Levenberg-Marquardt (LM), Quasi-Newton (QN) and Conjugate-Gradient (CG) were used as training algorithms in ANN. Hyperbolic tangent sigmoid (HTS) and logarithmic sigmoid (LS) transfer functions and different neuron numbers in hidden layer were tested in each different ANN structure. The performances of ANN constructions were determined by calculating Root Mean Squares Error (RMSE), Correlation Coefficient (R) and Nash-Sutcliffe Coefficient (E). In the generated rainfall-runoff model, all ANN structures have yielded satisfactory results, however ANN-QN has been determin...
In this study, a regional flood frequency analysis (RFFA) was applied to 33 stream gauging statio... more In this study, a regional flood frequency analysis (RFFA) was applied to 33 stream gauging stations in the Eastern Black Sea Basin, Turkey. Homogeneity of the region was determined by discordancy (D i) and heterogeneity measures (H i) based on L-moments. Generalized extreme-value, lognormal, Pearson type III, and generalized logistic distributions were fitted to the flood data of the homogeneous region. Based on the appreciate distribution for the region, flood quantiles were estimated for return periods of T=5, 10, 25, 50, 100, and 500 years. A non linear regression model was then developed to determine the relationship between flood discharges and meteorological and hydrological characteristics of the catchment. In order to compare with regression analysis, artificial bee colony algorithm (ABC) and teaching-learning based optimization (TLBO) models were developed. The equations were obtained by using the ABC and TLBO algorithms for the estimation of flood discharges for different return periods. The analysis showed that the TLBO and ABC results were superior to the regression analysis. Error values indicated that TLBO method yielded better results for estimation of flood quantiles for different independent variables.
The role of hydropower in meeting Turkey's electric energy demand
Energy Policy, 2006
... Keywords: Turkey's energy sources; Hydro and small hydro electric potential; Ele... more ... Keywords: Turkey's energy sources; Hydro and small hydro electric potential; Electric demand. Article Outline. 1. Introduction 2. Hydroelectric power 3. Turkey's hydroelectric power potential 3.1. ... 3.1. A general view to Turkey's energy status. ...
The Importance of Hydropower Plants in Turkey's Energy Planning
General Directorate of …, 2007
... Table 4. Distribution of under design hydro power plants according to their hydro capacity Cl... more ... Table 4. Distribution of under design hydro power plants according to their hydro capacity Classification Number of ... Dincer, I., The role of exergy in energy policy making, 2002. ... Yuksel, I., Yuksek O., Onsoy, H., An analysis of production hydroelectric energy in the Eastern Black ...
Energy is considered to be a key player in the generation of wealth and also a significant compon... more Energy is considered to be a key player in the generation of wealth and also a significant component in economic development. This makes energy resources extremely significant in the world. Efforts to prevent negative impacts of Hydroelectric Power Plants (HEPP) or to evaluate the measures to be taken to minimize these impacts are carried out within the scope of Environmental Impact Assessment (EIA). However, the existing EIA process in the environment has become inadequate to provide environmental standards. This has made it necessary to develop the Cumulative (CEIA) and Strategic (SEA) Environmental Assessments, which are the advanced stages of the traditional EIA. The CEIA is the assessment of the effects of an action along with other human activities in the past, present or future, leading to environmental impacts. The SEA, a tool for the implementation of sustainable development, is defined as the process of evaluation of possible negative effects of plans, programs and policies on the environment and the process of reducing these impacts. In this study, the problems and inadequacies encountered in the implementation of EIA in HEPP projects have been examined and the innovations brought by CEIA and SEA to environmental management and the necessity of these processes have been evaluated with case studies. At the end of the study, some suggestions have been made to better implement the CEIA and SEA processes.
Bu calismada, Giresun ili Aksu deresi uzerinde bulunan D22A116 numarali Akim Gozlem Istasyonu'... more Bu calismada, Giresun ili Aksu deresi uzerinde bulunan D22A116 numarali Akim Gozlem Istasyonu'nda olculmus gunluk ortalama akis ve 17034 numarali Giresun Meteoroloji Istasyonu'nda olculmus gunluk toplam yagis verileri kullanilarak tasarlanmis 5 girdi modeli kullanilmis, farkli Yapay Sinir Agi (YSA) yapilari ile noktasal yagis-akis modeli olusturulmustur. Olusturulan yagis-akis modelinde; YSA’da egitim algoritmasi olarak Levenberg-Marquardt (LM), Quasi-Newton (QN) ve Conjugate-Gradient (CG) kullanilmistir. Her farkli YSA yapisinda, Hiperbolik Tanjant Sigmoid (HTS), Logaritmik Sigmoid (LS) transfer fonksiyonlari ve gizli katmanda farkli noron sayilari denenmistir. YSA yapilarinin performanslari Ortalama Hata Kareleri Karekoku (RMSE), Korelasyon Katsayisi (R) ve Nash-Sutcliffe Katsayisi (E) hesaplanarak belirlenmistir. Olusturulan yagis-akis modelinde tum YSA yapilari iyi sonuclar uretilmis, ancak en iyi yapi olarak YSA-QN belirlenmistir (RMSE=12.090, R=0.806, E=0.649).
Bu calismada, Adana Ili Seyhan Havzasi’nda meydana gelen taskina ait saatlik debi verileri kullan... more Bu calismada, Adana Ili Seyhan Havzasi’nda meydana gelen taskina ait saatlik debi verileri kullanilarak taskin otelenme calismasi yapilmistir. Akarsu uzerindeki E18A025 nolu Akim Gozlem Istasyonu'nda (AGI) ve bu AGI'nun 5,044 km mansabinda yer alan D18A054 nolu AGI'nda gozlenen birer saat aralikli hidrograf verileri kullanilmistir. Istasyonlarda olculen degerler ile hidrolik ve hidrolojik modellerin sonuclari karsilastirilmistir. Calismada hidrolojik modellerden Muskingum ve SCS; hidrolik modeller olarak da Kinematik Dalga, Muskingum-Cunge ve Dinamik yontemleri uygulanmistir. Olculen ve modellerden hesaplanan degerler arasindaki Hatalarin Ortalama Karekoku (HOK), Ortalama Mutlak Hata (OMH) ve Belirlilik Katsayisi (R 2 ) degerleri hesaplanmis ve yontemlerin performanslari irdelenerek hangi yontemin daha iyi sonuc verdigi degerlendirilmistir. Calisma sonunda, Muskingum Yonteminin en iyi tahmini verdigi, Muskingum-Cunge, SCS ve Kinematik Yontemlerinin tahminlerinin de kabul...
Journal of the Croatian Association of Civil Engineers, 2020
Predviđanje maksimalnih godišnjih poplavnih protoka primjenom umjetnih neuronskih mreža U radu se... more Predviđanje maksimalnih godišnjih poplavnih protoka primjenom umjetnih neuronskih mreža U radu se istražuje primjenjivost pristupa umjetnih neuronskih mreža (ANN) za određivanje maksimalnih godišnjih protoka. Uspoređuje se učinkovitost triju modela neuronskih mreža: višeslojne perceptronske neuronske mreže (MLP_NN), generalizirane neuronske mreže usmjerene prema naprijed (GFF_NN) i analiza osnovnih komponenata pomoću neuronskih mreža (PCA_NN). Predloženi pristupi primijenjeni su na 33 vodomjerne. Utvrđeno je da je optimalna metoda PCA_NN s tri skrivena sloja prikladnija za određivanje maksimalnih godišnjih protoka od optimalnih modela MLP_NN i GFF_NN.
A combined field and laboratory investigation was conducted to assess five options for creation o... more A combined field and laboratory investigation was conducted to assess five options for creation of a recreational beach on a steep, armored shoreline on the eastern Black Sea coast. All designs incorporated a beach nourishment project placed between two existing, shore-normal, rubble-mound groins. Alternatives included the placement of a nearshore berm, longshore extensions added to the existing groins, and shore-parallel breakwaters. Several alternatives are reviewed for quantifying the performance of each design, including assessment of the change in shoreline position and project volume retained between the groins. Dimensionless benefits and benefit-cost ratios are quantified, and recommendations made on how to select the best outcome from a benefit-to-cost standpoint when options including hard structures are incorporated into a beach nourishment project design.
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