Civil Engineering / İnşaat Mühendisliği
Permanent URI for this collectionhttps://hdl.handle.net/11147/13
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Conference Object Citation - Scopus: 1Decoding and Predicting the Attributes of Urban Public Spaces With Soft Computing Models and Space Syntax Approaches(Education and research in Computer Aided Architectural Design in Europe, 2023) Yönder, Veli Mustafa; Doğan, Fehmi; Çavka, Hasan Burak; Tayfur, Gökmen; Dülgeroğlu, ÖzümPeople spend a considerable amount of time in public spaces for a variety of reasons, albeit at various times of the day and during season. Therefore, it is of utmost importance for both urban designers and local authorities to try to gain an understanding of the architectural qualities of these spaces. Within the scope of this study, squares and green parks in Izmir, the third largest city in Turkey, were analyzed in terms of their dimensions, landscape characteristics, the quality of their semi-open spaces, their landmarks, accessibility, and overall aesthetic quality. Using linear predictor, general regression neural networks, multilayer feed-forward neural networks (2-3-4-5-6 nodes), and genetic algorithms, soft computing models were trained in accordance with the results of the conducted analyses. Meanwhile, using space syntax methodologies, a visibility graph analysis and axial map analysis were conducted. The training results (i.e., root mean square error, mean absolute error, bad prediction rates for testing and training phases, and standard deviation of absolute error) were obtained in a comparative table based on training times and root mean square error values. According to the benchmarking table, the network that most accurately predicts the aesthetic score is the 2-node MLFNN, whereas the 6-node MLFN network is the least successful network. © 2023, Education and research in Computer Aided Architectural Design in Europe. All rights reserved.Book Part Citation - Scopus: 4Application of Fuzzy Logic in Water Resources Engineering(Elsevier, 2022) Tayfur, GökmenThis chapter introduces the fundamentals of fuzzy logic (FL), fuzzy sets, and fuzzy model components such as the fuzzification, the fuzzy rule base, the fuzzy inference engine, and the defuzzification. The processes of the fuzzy model components are presented by working on the examples from the water resources engineering application problems. This chapter also discusses the merits and the shortcomings of the fuzzy modeling. Hydrological processes have inherent source of uncertainty, for which the fuzzy set theory can be an effective solution tool. © 2023 Elsevier Inc. All rights reserved.Book Part Citation - Scopus: 1Developments in Sediment Transport Modeling in Alluvial Channels(Elsevier, 2022) Tayfur, GökmenThis chapter discusses the developments in the mathematical modeling of sediment transport dynamics in alluvial channels. Starting with early experimental and empirical studies, it goes on to treating the processes in 1D, 2D, and 3D uniform sediment transport. Finally, it describes the treatment of the processes in 3D nonuniform sediment transport considering turbulence effects. While introducing the advancements in mathematical modeling of the dynamics, the chapter also discusses the outstanding issues like the treatment of the particle fall velocity, the particle velocity, and sediment transport rate function. © 2023 Elsevier Inc. All rights reserved.Book Part Citation - Scopus: 3Real-Time Flood Hydrograph Predictions Using Rating Curve and Soft Computing Methods (ga, Ann)(Elsevier, 2022) Tayfur, GökmenThis chapter introduces hydraulic and hydrologic flood routing methods in natural channels. It details hydrological flood routing methods of the Rating Curve and Muskingum. Based on the rating curve method (RCM), it presents real-time flood hydrograph predictions using the genetic algorithm (GA-based RCM) model. In addition, it presents how to make real-time flood hydrograph predictions using the artificial neural network (ANN). The chapter briefly introduces the basics of GA and details how to calibrate and validate the GA-based RCM model using measured real-time flood hydrographs. Similarly, after giving the basics of ANN, it shows how to train and test the ANN model using measured hydrographs. Real hydrograph simulations by the RCM, GA-based RCM, and ANN are presented, and merits of each model are discussed. © 2023 Elsevier Inc. All rights reserved.Conference Object Citation - Scopus: 2Experimental Study of the Evolution of the Breach and the Discharge Through the Breach Resulting From Piping Due To Seepage at the Earth-Fill Dam Bottom(Avestia Publishing, 2022) Güney, Mehmet Şükrü; Dumlu, Emre; Okan, Merve; Bor, Aslı; Aklık, Pelin; Tayfur, GökmenPiping is one of the main causes of the earth-fill dam failures. Most of the researchers realizing numerical analyses make some simplified assumptions concerning the shape of the breach and the discharge of water flowing through the breach. The aim of this study is to realize experiments to provide data needed to perform numerical analyses by making more realistic assumptions. The dam having a height of 0.6 m, a bottom width of 2 m and a crest width of 0.20 m is built in a channel 1 m wide, 0.81 m high and 6.14 m long. The evolution of the breach and the discharge through the breach resulting from piping due to seepage at the earth-fill dam bottom was investigated experimentally. The evolution of the dam failure is recorded by six cameras located at different locations. The time-varied of the breach areas at upstream and downstream sides are determined by applying the Gauss Area functions. The discharge of water through the breach and average outflow velocity are determined by using the continuity equation.Conference Object Citation - Scopus: 2Lighting Quality and Work Performance Based on Glazing Types and Dynamic Led Lighting(IEEE, 2022) Köse, Fatma Büşra; Tayfur, Gökmen; Duran, Hasan Engin; Kazanasmaz, Zehra TuğçeThe combination of daylight characteristics and LED lighting quantities determines offices' visual environment. Lighting conditions can influence office workers' health and work performance. This study is an experimental one containing lighting measurements in two offices, subjective performance tests, and questionnaires to find out how work performance, lighting preferences, and satisfaction with lighting quality modify in terms of various glass types and dynamic LED lighting quantities. Glass types have strong impacts on contrast tests on paper and luminance which are corresponding to work performance. Regarding lighting quality, it strongly relates to the homogeneity of light, the impression of artificial light and the perception of objects' textures and color, contrast balance between paper and the surrounding. When the glass was modified in offices, we observed that participants preferred to change the CCT setting of LED by remote control, and in relation to that the eye-level illuminance and SPDs showed significant changes. So, the findings depicted the importance of the choice of glass types concerning LED lighting settings in terms of the above variables.Article Alaşehir Alt Havzasının (gediz Havzası, Batı Anadolu) Nem Değişimi Yöntemine Göre Yeraltısuyu Besleniminin Değerlendirilmesi(2021) Durukan, Seda; Şimşek, Celalettin; Tonkul, Serhat; Baba, Alper; Tayfur, GökmenGediz havzası Ege Bölgesinin en önemli havzalarından biridir. Çalışma alanı Gediz havzası içerisinde bulunan Alaşehir alt havzasıdır. Bu çalışma kapsamında Alaşehir alüvyon akifere çok sayıda araştırma kuyusu açılmış olup, araştırma kuyularında zemin karakterizasyonu belirlenmiş ve bazı kuyulara da zemin nem sensörleri konumlandırılarak yeraltısuyu beslenimi hesaplanmıştır. Doygun olmayan bölgedeki zeminlerde nem değişim yöntemi ile yağıştan sonra zemin nem değişimleri belirlenerek yağıştan beslenme miktarı tespit edilebilmektedir. Bu kapsamda alüvyon akifere 5 farklı noktada özel açılan kuyularda 5, 10 ve 15 m derinliklerde nem sensörleri vasıtası ile zemin nemi, sıcaklığı ve tuzluluğu ölçülmüştür. Çalışma alanında seçilen kuyularda zeminin suya doygun olmayan bölgesinde gerçekleştirilen hacimsel su içeriklerine göre mevsimsel değişiklikleri ortaya konulmuş ve yağıştan kaynaklanan beslenme miktarı belirlenmiştir. Elde edilen ölçümler sonucunda, çalışma alanındaki alüvyon akiferdeki yeraltısuyu beslenimi en az 40,81 ile en çok 77,12 mm olacak şekilde, ortalama olarak da 56,83 mm hesaplanmıştır. Ayrıca, ilk kez derin kuyular vasıtası ile yeraltısuyu besleniminde kullanılan zemin nem değişim yönteminin limitasyonları da bu çalışma kapsamında tartışılmıştır.Article Küçük Menderes Havzası Su Kaynaklarının Sürdürülebilirliği(Dicle Üniversitesi, 2018) Şahin, Yavuz; Baba, Alper; Tayfur, GökmenTürkiye’nin batısında yer alan Küçük Menderes Havzası, tarımsal faaliyetin yoğun olduğu verimli topraklara ve ürün çeşitliliğine sahiptir. Havzada son otuz yıldır yeraltı suyu seviyesinde ciddi bir düşme gözlemlenmektedir. Bunun sebebi yoğun tarımsal sulama, hayvancılık ve sanayileşmenin getirdiği etkilerdir. Günümüzde Devlet Su İşleri Genel Müdürlüğü’nün yörede su kaynaklarının etkin kullanımına yönelik çalışmaları hız kazanmıştır. Pek çok baraj (Beydağ, Uladı, Aktaş vb.), regülatör ve basınçlı sulama şebekeleri döşenmesi çalışmaları devam etmekte yahut planlanmaktadır. Ancak, yeraltı suyu tüketimi gün geçtikçe artmaktadır. Mevcut durum da halk sulamasının %91,8 yeraltı suyundan karşılanmaktadır. Ancak, bu oran 2020’de % 66,7’ye düşürülmesi ve kalan diğer sulamanın (%28,9) DSİ tarafından yüzeysel sularla yapılması planlanmıştır. Bununla birlikte, havzadaki yüzeysel su kaynakların daha aktif ve verimli kullanılması için, alandaki yüzeysel su kaynaklarını kirleten unsurlarında minimize edilmesi gerekmektedir.Book Citation - Scopus: 6Climate Change and Its Effects on Water Resources: Issues of National and Global Security(Springer, 2011) Baba, Alper; Gündüz, Orhan; Friedel, Michael J.; Tayfur, Gökmen; Howard, Ken W.F.; Chambel, AntonioNational and global security can be assessed in many ways but one underlying factor for all humanity is to access to reliable sources of water for drinking, sanitation, food production and manufacturing industry. In many parts of the world, population growth and an escalating demand for water already threaten the sustainable management of available water supplies. Global warming, climate change and sea level rise are expected to intensify the resource sustainability issue in many water-stressed regions of the world by reducing the annual supply of renewable fresh water and promoting the intrusion of saline water into aquifers along sea coasts where 50% of the global population reside. Pro-active resource management decisions are required, but such efforts would be futile unless reliable predictions can be made to assess the impact of the changing global conditions that would impart upon the water cycle and the quality and availability of critical water reserves.Conference Object Upscaling Surface Flow Equations Depending Upon Data Availability at Different Scales(Springer Verlag, 2003) Tayfur, GökmenSt. Venant equations, which are used to model sheet flows, are point-scale, depth-averaged equations, requiring data on model parameters at a very fine scale. When data are available at the scale of a hillslope transect, the point equations need to be upscaled to conserve the mass and momentum at that scale, Hillslope-scale upscaled model must be developed if data are available at that scale. The performance of the three models applied to simulate flows from non-rilled surfaces revealed that the hillslope-scale upscaled model performs as good as the point-scale model though it uses far less data. The transectionally-upscaled model slightly underestimates the observed data.