Yazarlar
- Yön, Burak(15)
- Onat, Onur(11)
- Gul, Muhammet(10)
- Utku, Anıl(9)
- Celik, Erkan(8)
- Etli, Serkan(8)
- Dal, Murat(6)
- Güngör, Gizem Nur(6)
- Yucesan, Melih(5)
- Öncü, Mehmet Emin(5)
- Akgül, Melek(4)
- Ergen, Burhan(4)
- Kaya, Sema Kayapinar(4)
- Mete, Suleyman(4)
- Akkurt, Nevzat(3)
- Ceylan, Ebru Nalan(3)
- Derse, Onur(3)
- Doğan, Gürkan(3)
- Güneyisi, Esra Mete(3)
- Karataş, Lale(3)
- Konurhan, Zekeriya(3)
- Polat, Elifcan Göçmen(3)
- Tam, Gürkan(3)
- Özceylan, Eren(3)
- Akar, Tuba(2)
- Başaran, Erkin(2)
- Calayır, Yusuf(2)
- Dalkılıç, Neslihan(2)
- Erdem, Necla Seval(2)
- Erguven, Gokhan Onder(2)
- Gör, Mesut(2)
- Harun, Zambri(2)
- Isik, Sevket(2)
- Işık, Erdem(2)
- Kanat, Gurdal(2)
- Peyneau, Pierre-Emmanuel(2)
- Serin, Faruk(2)
- Uslu, Ali(2)
- Varolgüneş, Sadık(2)
- Yilmaz, Deniz(2)
Yayınlar
- MakaleYalnız künye2020Scopus SJRQ1Futuristic airport: A sustainable airport design by integrating hesitant fuzzy SWARA and hesitant fuzzy sustainable quality function deployment
Kayapinar Kaya, Sema; Erginel, Nihal
The interest of researchers and airport authorities towards sustainable airports is increasing day by day. Futuristic airport designs will be innovative in achieving sustainable development practices such as clean and affordable energy, protection of natural resources, waste reduction, natural features and green space around an airport, sustainable transportation system, natural storm water management of airports, etc. In classical Quality Function Deployment, crisp numbers are used to determine the priorities of the passenger requirements, design requirements, and their relationship matrix to evaluate airport quality. However, vagueness and impreciseness are inevitable uncertainties in those kinds of human judgments, which are generally realized by linguistic terms, and traditional Quality Function Deployment is not associated with “sustainability.” The main contribution of this paper is to present a new approach that integrates Hesitant Fuzzy Stepwise Weight Assessment Ratio Analysis and Hesitant Fuzzy Sustainable Quality Function Deployment method to enhance the sustainable airport quality. Hesitant fuzzy set theory reflects the hesitancy in human nature while making a decision to the fuzzy numbers, compared to other fuzzy set theories, such as traditional fuzzy sets, type-2 fuzzy sets, etc. In this study, the importance degrees of sustainable passenger requirements were evaluated by considering Hesitant Fuzzy Stepwise Weight Assessment Ratio Analysis in the first stage of Hesitant Fuzzy Sustainable Quality Function Deployment method. Then sustainable design requirement was prioritized to develop the sustainable quality management of the airport. Finally, a case study concerning the sustainable development of the airport was used to elucidate the feasibility and rationality of the proposed framework. The results obtained from the case study showed that Hesitant Fuzzy Sustainable Quality Function Deployment could be a practical and structural methodology in the early planning stage of a sustainable airport design.
AtıfScopus68WoS54OpenAlex74
İncele - MakaleAçık Erişim2020Scopus SJRQ2Seismic performance evaluation of regular and irregular composite moment resisting frames
Etli, Serkan; Güneyisi, Esra Mete
In this study, the seismic behavior of regular and irregular composite moment resisting frame (CMRF) buildings was investigated. To this aim, 5, 8, 10, 13 and 15-story CMRFs having concrete filled steel tube columns and composite beams were designed at high ductility level and their performances were evaluated comparatively. The case study CMRF structures were categorized into two groups as regular and irregular in elevation. Examined irregular structures have setbacks in different story levels. During the design and performance analysis, SeismoStruct software was employed. Nonlinear static pushover and incremental dynamic analyses were used in the seismic performance assessment. The uniform and triangular load distributions were considered in the pushover analysis while a total of 22 earthquake acceleration records were utilized in the dynamic analysis. The variation in the lateral response, global yielding value, interstory drift, behavior factor, inherent strength factor, overstrength factor, and ductility factor were examined for the regular and irregular CMRF structures. It was observed that the regular CMRFs were more consistent with the design assumptions as compared to the irregular ones. Moreover, the former exhibited more uniform non-elastic demands over the building height according to the results of the incremental dynamic analysis. Under the seismic scenario adopted, all the building types yielded higher values of the behavior factor complied with the limits available in the code.
AtıfScopus15WoS10OpenAlex32İncele - MakaleYalnız künye2020Scopus SJRQ2Seismic vulnerability assessment of RC buildings according to the 2007 and 2018 Turkish seismic codes
Yön, Burak
Fragility curves are useful tools to estimate the damage probability of buildings owing to seismic actions. The purpose of this study is to investigate seismic vulnerability of reinforced concrete (RC) buildings, according to the 2007 and 2018 Turkish Seismic Codes, using fragility curves. For the numerical analyses, typical five-and seven-storey RC buildings were selected and incremental dynamic analyses (IDA) were performed. To complete the IDAs, eleven earthquake acceleration records multiplied by various scaling factors from 0.2g to 0.8g were used. To predict nonlinearity, a distributed hinge model that involves material and geometric nonlinearity of the structural members was used. Damages to confined concrete and reinforcement bar of structural members were obtained by considering the unit deformation demands of the 2007 Turkish Seismic Code (TSC-2007) and the 2018 Turkey Building Earthquake Code (TBEC-2018). Vulnerability evaluation of these buildings was performed using fragility curves based on the results of incremental dynamic analyses. Fragility curves were generated in terms of damage levels occurring in confined concrete and reinforcement bar of structural members with a lognormal distribution assumption. The fragility curves show that the probability of damage occurring is more according to TBEC-2018 than according to TSC-2007 for selected buildings.
AtıfScopus16WoS12OpenAlex7İncele - MakaleAçık Erişim2020Scopus SJRQ2An integrated approach of best-worst method (bwm) and triangular fuzzy sets for evaluating driver behavior factors related to road safety
Moslem, Sarbast; Gul, Muhammet; Farooq, Danish; Celik, Erkan; Ghorbanzadeh, Omid; Blaschke, Thomas
Driver behavior plays a major role in road safety because it is considered as a significant argument in traffic accident avoidance. Drivers mostly face various risky driving factors which lead to fatal accidents or serious injury. This study aims to evaluate and prioritize the significant driver behavior factors related to road safety. In this regard, we integrated a decision-making model of the Best-Worst Method (BWM) with the triangular fuzzy sets as a solution for optimizing our complex decision-making problem, which is associated with uncertainty and ambiguity. Driving characteristics are different in different driving situations which indicate the ambiguous and complex attitude of individuals, and decision-makers (DMs) need to improve the reliability of the decision. Since the crisp values of factors may be inadequate to model the real-world problem considering the vagueness and the ambiguity, and providing the pairwise comparisons with the requirement of less compared data, the BWM integrated with triangular fuzzy sets is used in the study to evaluate risky driver behavior factors for a designed three-level hierarchical structure. The model results provide the most significant driver behavior factors that influence road safety for each level based on evaluator responses on the Driver Behavior Questionnaire (DBQ). Moreover, the model generates a more consistent decision process by the new consistency ratio of F-BWM. An adaptable application process from the model is also generated for future attempts.
AtıfScopus96WoS83OpenAlex93İncele - MakaleYalnız künye2020Scopus SJRQ3A fuzzy-based occupational health and safety risk assessment framework and a case study in an international port authority
Gul, Muhammet
Ports are complex systems that play a crucial role in the transportation of maritime-related products and services. Since ports face various safety issues in design, installation, operation and maintenance processes, there are many aspects open for improvement in Occupational Health and Safety risk assessment and it is required to deal with risks, reduce them to an acceptable level and control. To struggle with emerging risks and manage this process better, a risk assessment framework is proposed for ports in this study. A case study is performed in a Turkish international port authority using the proposed framework. Fuzzy Analytic Hierarchy Process (FAHP), which is a commonly used fuzzy multi-criteria decision-making method, was used in weighting two risk factors: likelihood and severity. The orders of priority of hazards were then determined by a fuzzy-based VIKOR method based on the output of FAHP. The proposed framework overcomes some drawbacks, including a lack of assignment on the weight to two risk assessment factors and lack of the high dependence of the prioritisation on the experts’ opinions. To validate the results, a sensitivity analysis was conducted. In conclusion, the study contributes to the applicability of the proposed framework to assess the risks in ports and provides a distinct risk prioritisation.
AtıfScopus43WoS39OpenAlex49İncele - MakaleAçık Erişim2019Comparison of the public and private university campusses in Turkey in terms of the sustainable – ecological parameters
Askin, Ali; Kaya, Sema Kayapinar; Dal, Murat
In this study, it is aimed to highlight the properties of the increasing number of the university campusses in Turkey in terms of sustainable and ecological properties. 5 public (Boğaziçi, Bülent Ecevit, Karabük, İstanbul Teknik, Ege) and 5 private (Özyeğin, Yeditepe, Bahçeşehir, Bilgi and Bilkent) universities are investigated in terms of sustainable and ecological campus criterias such as “Energy Management”, “Sustainable Transportation”, “Waste Management”, “Water Management”, “Environmental Management” and “Sustainable Education”.
AtıfOpenAlex13TR Dizin9
İncele - MakaleAçık Erişim2019Doğal afet durumu için cbs tabanlı maksimum kapsama yerleşim modeli: tunceli örneği
Celik, Erkan; Özceylan, Eren; Mete, Süleyman; Özkan, Barış
Afet zamanlarında insani lojistik açısından afetzedelerin barınma yerlerine erişimi önemli bir problemdir. İnsani lojistik yönetiminin önündeki en büyük zorluklardan biri de fazla sayıdaki afetzedelerin koordinasyonudur. Özellikle, olay mahallindeki mekânsal verinin eksikliği etkin bir planlamanın önündeki en büyük engellerden biridir. Bu çalışmada, afet zamanlarında kullanılmak üzere potansiyel afetzedelerin ilgili barınaklara atanması için Coğrafi Bilgi Sistemi (CBS) tabanlı bir çözüm yaklaşımı önerilmiştir. Ulaşılan afetzede sayısını maksimize etmek için ArcGIS’in maksimum kapsama yerleşim modeli kullanılmış ve Tunceli ili üzerinde test edilmiştir. Tunceli şehir merkezindeki 2.121 adet binaya 31.076 kişi, nüfus olarak atanmış ve 5 barınma merkezi ile model çalıştırılmıştır. Daha sonra farklı sayıda barınma merkezi ve kapsama alanları altında senaryo analizleri gerçekleştirilmiş ve sonuçlar yorumlanmıştır. Elde edilen sonuçlar, önerilen modelin afetzedelerin barınma merkezlerine atanmasında etkin bir araç olduğunu göstermiştir.
AtıfOpenAlex4TR Dizin2İncele - MakaleAçık Erişim2019The Impact of Urbanization On Energy Consumption and Carbon Emissions in Turkey
Kahraman, Gökhan
Turkey's economic development in terms of urbanization, consumption of electricity is a significant pressure on the natural environment. In order to reduce the effects of this pressure in parallel with economic growth, it is necessary to reduce the dependence on foreign sources in energy while reducing the amount of carbon emissions that cause environmental pollution. Therefore, Turkey's economic growth of urbanization in order to continue in a healthy way, the relationship between the amount of energy consumption and carbon emissions need to be better understood. The target to reduce the economic and environmental impacts of economic growth and urbanization with increasing energy needs to the minimum should be to use renewable energy sources efficiently. The aim of this study urbanization in Turkey, the relationship between electricity consumption and carbon emissions is to examine the amount of time series analysis. The increase in the amount of carbon emission, the increase in population and the increase in electricity demand in comparison with years and sectoral basis were compared. discussing the results obtained from the graph are interpreted in how it has changed that and more weight which results results obtained from the graphic industry where the bet is causing the increase of electricity demand with urbanization between 1990-2017 years in Turkey. Graphic shows the results obtained from the last 27 years the amount of carbon emissions in Turkey, the population and electricity demand is increasing in parallel with each other. Especially the rise in demand for electricity and carbon emissions, but not appear as a result of this parallel Turkey's recent emphasis on renewable energy sources.
AtıfOpenAlex15TR Dizin11İncele - MakaleYalnız künye2019Scopus SJRQ1Earthquake Damage to Nonstructural Elements of Reinforced Concrete Buildings during 2011 Van Seismic Sequence
Yön, Burak; Onat, Onur; Öncü, Mehmet Emin
Infill and partition walls as nonstructural elements are generally constructed with hollow brick masonry and briquette as single or multilayered vertical walls. The seismic responses of infill walls and reinforced concrete (RC) framed buildings have been investigated with field observations after earthquakes all over the world. This study focuses on the reasons infill and partition walls failed as a result of the October 23, 2011 (Mw=7.2), and November 9, 2011 (Mw=5.7), Van earthquakes in Turkey. In this paper, in-plane, out-of-plane, and combined failure mechanisms of single and multilayered infill walls enclosed within reinforced concrete structures were investigated, and construction rules were suggested. To limit the failure of nonstructural elements enclosed within an RC frame, design and construction requirements should be included in the seismic code by adopting suitable solutions for both in-plane and out-of-plane behavior. This paper will be a reference for future studies that investigate infill wall damage. (c) 2019 American Society of Civil Engineers.
AtıfWoS51OpenAlex62İncele - MakaleAçık Erişim2019Public transportation graph: A graph theoretical model of public transportation network for efficient trip planning
Serin, Faruk; Mete, Suleyman
The presentation and usage of traditional graphs is very important for effective and fast solution of routing in public transportation. However, the traditional graph approach is unable to consider the passenger requests such as total travel time, minimum number of transfer and total distance of travel without pre-processing and/or post-processing. Moreover, the vehicles are not represented on traditional graph. In this paper, after analyzing the different kind of graphs, we propose a novel graph named as public transportation graph. The proposed graph models the public transportation system and considers distance, waiting time, travel time, self-transportation and number of transfers simultaneously for efficient trip planning. In this way, passenger requests can be met without pre-processing and post-processing. In addition, the vehicles are also considered and demonstrated in the proposed graph.
AtıfWoS1OpenAlex4TR Dizin1İncele - MakaleYalnız künye2019Scopus SJRQ1Assessment of hydraulic properties of technosols using Beerkan and multiple tension disc infiltration methods
Yilmaz, Deniz; Bouarafa, Sofia; Peyneau, Pierre-Emmanuel; Angulo-Jaramillo, Rafael; Lassabatere, Laurent
The increasing global urban sprawl requires large amounts of materials, putting huge pressure on numerous natural resources. In particular, vast quantities of soils are used to create infrastructures or green spaces associated with new developments. Alternative solutions aimed at alleviating soil consumption are thus being encouraged. Creating urban soils by recycling waste from industrial and construction activities is feasible, but apart from their support function the resulting technosols should also be able to provide some ecosystem services such as the capacity to infiltrate water and filter contaminants. Various methods are routinely used for in situ characterization of the hydraulic behaviour of natural soils, but their ability to assess the hydraulic properties of technosols remains unclear. Indeed, technosols formed from recycled waste differ markedly from natural soil because they often contain a considerable proportion of coarse artefacts that affect their structure. In this study, results obtained by two distinct methods (ponding and tension infiltrometry), associated with two data processing methods (Beerkan estimation soil transfer (BEST) and numerical inversion), on a set of infiltration data measured on experimental plots made of technosols have been compared with each other. Both methods provided similar results and thus proved to be reliable when applied to technosols. Highlights: Reuse of by-products from anthropogenic activities is crucial to alleviate the consumption of natural soil. Hydraulic properties of technosols must be monitored to assess some of the ecosystem services they can provide. BEST and numerical inversion of multiple tension disc infiltration data gave consistent results. Reliability of the hydraulic characterization methods used for technosols deserves further inquiry.
AtıfScopus10WoS10OpenAlex12İncele - Derleme MakaleAçık Erişim2019Scopus SJRQ2ANN and ANFIS Approaches to Calculate the Heating and Cooling Degree Day Values: The Case of Provinces in Turkey
Işık, Erdem; İnallı, Mustafa; Celik, Erkan
Energy analysis plays a vital role in developing an optimum and cost-effective design for the heating, ventilating and air conditioning system of a building. The values of heating degree days (HDD) and cooling degree days (CDD) are used to analyze the demand for energy for buildings. In this study, the HDD and CDD values for Turkey were calculated using estimated temperature values. An artificial neural network (ANN) and an adaptive network-based fuzzy inference system (ANFIS) were applied for the estimation of temperature values. The Levenberg–Marquardt training algorithm was used for the feedforward backpropagation of the ANN, whereas the Sugeno-type fuzzy inference system was used for the ANFIS. Meteorological data from the last 11 years were used for the proposed approaches, and these were applied to different stations (n = 50) of the Turkish State Meteorological Service. In relation to the insulated building design, base temperatures have been considered as 16 °C and 18 °C for the HDD and 22 °C and 24 °C for the CDD based on a literature review. Two novel maps were prepared for the CDD and HDD. The calculated degree days and the maps are consistent with those from the Turkish State Meteorological Service.
AtıfScopus13WoS13OpenAlex18İncele - MakaleAçık Erişim2019Scopus SJRQ3Optimization of medical waste routing problem: The case of TRB1 region in Turkey
Mete, Suleyman; Serin, Faruk
A fundamental problem concerning medical waste disposal is the evaluation of the real and potential risks arising from waste with the focus on the risk of infection. Therefore, the optimization of medical waste routing from collection to disposal center can minimize the risk of infection. The routing of medical waste considers significant to determine potential routes and select the route with minimum distance. The management of the medical waste is important decision for environmental sustainability and includes the collection, transportation and disposal of these materials. In this paper, a geographic information system (GIS) solution approach is proposed to determine the best location of disposal center. Proposed approach is applied to medical waste transportation between 167 health institutions (collection centers) and predetermined 5 disposal centers through TRB1 region in Turkey, which consist of Malatya, Elazığ, Bingöl and Tunceli provinces. The results of case study are examined and suggestions for future research are provided.
AtıfScopus7OpenAlex7İncele - MakaleAçık Erişim2018Tunceli İlindeki Trafik Kazası Oranlarının İncelenmesi
Zengin, Bilgin; Arslannur, Bircan
Bu çalışmada, Tunceli ilinde 2012 - 2016 yılları arasında meydana gelen trafik kazası sayıları ile bu kazalardaki ölü ve yaralı sayıları incelenmiş, sonuçlar Türkiye oranlarıyla karşılaştırılmıştır. İncelenen yıllarda araç başına düşen kaza, ölüm ve yaralı yüzdelik oranları belirlenmiştir. Anlamlı bir değerlendirme yapabilmek için yüzdelik oranların ortalamaları dikkatlice hesaplanmıştır. Ayrıca incelenen yıllar için Tunceli ilinin ve Türkiye’nin kişi başına düşen araç sayıları belirlenmiş ve sonraki analizler için ortalamaları hesaplanmıştır. Buradan Türkiye’de kişi başına düşen araç sayısının Tunceli ili ortalamasından 2.83 kat büyük olduğu belirlenmiştir. Bu durumun aksine araç başına düşen kaza yüzdelik ortalamalarına bakıldığında ise; Tunceli ili oranının Türkiye geneli oranından 2.33 kat daha büyük olduğu görülmektedir. Buna paralel olarak, araç başına düşen ölü ve yaralı yüzdelik oran ortalamalarının da Türkiye geneli ortalamalarından sırasıyla 2.67 ve 2.77 kat daha büyük olduğu görülmüştür. Diğer yandan, Tunceli ilinde kişi başına düşen araç sayısının Türkiye ortalamasından çok düşük olmasına rağmen kaza, ölüm ve yaralı oranlarının büyük oluşunun nedenleri de araç cinsi bakımından incelenmiştir. Bu açıdan bakıldığında, Tunceli ili ve Türkiye için toplu taşıma (otobüs + minibüs) araçlarının genel araç toplamı yüzdelerinin sırasıyla %9.94 ve %3.45 olduğu hesaplanmıştır. Buradan Tunceli ilinin toplu taşıma araçları oranının Türkiye geneli oranından 2.88 kat daha büyük olduğu görülmektedir. Bu değerler bize Tunceli ilindeki trafik kazalarının toplu taşıma araçları ile yapılma olasılığının daha büyük olduğunu göstermektedir. Böylece, elde ettiğimiz bu veriler Tunceli ilindeki kazalarda ölü ve yaralı oranlarının Türkiye ortalamasından yaklaşık 3 kat büyük olması durumunu açıklamaktadır.
AtıfOpenAlex3TR Dizin3İncele - MakaleYalnız künye2018Scopus SJRQ1Physical properties of structural soils containing waste materials to achieve urban greening
Yilmaz, Deniz; Cannavo, Patrice; Séré, Geoffroy; Vidal-Beaudet, Laure; Legret, Michel; Damas, Olivier; Peyneau, Pierre-Emmanuel
AtıfOpenAlex75İncele - BildiriAçık Erişim2018Investigation of Earthquake Behaviour of Construction System and Materials in Traditional Turkish Architecture
Yardimli, Seyhan; Dal, Murat; Mihlayanlar, Esma; Cattani, C; Atangana, A; Bulut, H; Hammouch, Z; Baskonus, HM; Mekkaoui, T; Agoujil, S
In this study, it is aimed to present a point of view regarding the behaviour of construction systems implemented in traditional Turkish architecture against earthquakes. In the scope of the study, examples of civil architecture were considered and their structures were evaluated as building elements such as foundation, wall and flooring. Traditional Turkish architecture construction systems can be evaluated in two parts. One of them is the wooden carcass system and the other is the unreinforced masonry system. In the wooden carcass system, the carrier is the load bearing elements used in horizontal and vertical directions. Intermediate parts (strut, diagonal etc.) are placed between these elements to form triangles. The triangles (strut, diagonal) used in the wooden skeleton system comprise highly resistant forms against earthquakes. Moreover, due to the internal structure and physical properties of the wood, which is the skeleton material, the flexibility that it maintains can meet the lateral loads of earthquakes. The second construction system which is the system addressed in this application, is the unreinforced masonry system. In this system, the loadbearing system itself is the walls, which are not resistant to lateral loads. In order to provide this flexibility beams (hatillar) are installed at certain intervals. After the wall is built to a certain height, a different material is laid allowing a plane of movement on the wall. Thus, when the wall is exposed to a lateral load, it escapes from the planes where the beams (hatillar) are present, and is protected against large damages by absorbing the earthquake load. In order to establish that the foundation of the structure can withstand earthquakes by movement, wood is placed at the lower part of the foundation above a layer of sand ensuring lateral movement and flexibility of the building. In traditional buildings the slabs are connected to the building walls with beams (hatillar). Through the agency of the beams (hatillar) formed at the connection points, the slabs can act as a mass so that they can meet the earthquake load. Allowing the structure to move makes it resistant to earthquakes, seismic isolators are used for this purpose by absorbing the earthquake load and moving the foundation of the structure.
AtıfWoS1OpenAlex4İncele - MakaleAçık Erişim2018Scopus SJRQ3Seismic assessment of existing RC buildings before and after shear-wall retrofitting
Onat, Onur; Yön, Burak; Calayir, Yusuf
The existing reinforced concrete (RC) buildings are analysed in the paper before and after shear-wall retrofitting. For numerical application, an existing RC building was selected and retrofitted with shear walls. Incremental dynamic analyses and static pushover analysis of these buildings were performed using the distributed plastic hinge approach. The results show that seismic retrofitting with shear walls increases rigidity and capacity of the building, while decreasing lateral displacements and damage.
AtıfScopus4WoS3OpenAlex3İncele - MakaleYalnız künye2018Scopus SJRQ2Fuzzy rule-based Fine–Kinney risk assessment approach for rail transportation systems
Gul, Muhammet; Celik, Erkan
Rail transportation is one of the most crucial public transportation types for big and crowded cities. In rail transportation systems, stakeholders face serious issues involved in workshops, stations, lines and their environments, and general office buildings. In order to reach an increased awareness and better occupational health and safety (OHS) management, a new risk assessment approach is proposed in this study. This approach includes a combination of Fine–Kinney method and a fuzzy rule-based expert system. It captures nonlinear causal relationships between Fine–Kinney parameters. Since there is a high level of vagueness involved in the OHS risk assessment data, the rule-based expert system is developed for probability (P), exposure (E), and consequence (C) for evaluating risk score. A case study is carried out in a rail transportation system in Istanbul/Turkey, and a comparison with the classical Fine–Kinney method is discussed. Results of the case study reveal risk clusters and corresponding control measures that should be taken into consideration. The study methodologically contributes to risk assessment in the knowledge, while case study in a real rail transportation system offers an insight into public transport industry in safety improvement.
AtıfScopus81WoS71OpenAlex86İncele - MakaleAçık Erişim2018Scopus SJRQ3Location and coverage analysis of bike-sharing stations in university campus
Mete, Suleyman; Cil, Zeynel Abidin; Özceylan, Eren
Background: Bike-sharing programmes have become popular in a large number of cities in order to facilitate bicycle use. Determining the location of bike sharing stations is vital to success of these programmes. Objectives: In this paper, a case study is applied to the Gaziantep University campus in order to find possible locations of the stations for users (students). The purpose is to minimize the total walking distance. Methods/Approach: Set and maximal covering mathematical models are considered to decide on coverage capability of determined 20 demand points and 20 potential bike stations. Then, the mathematical models of P-center and P-median are used to build possible stations and to allocate demand points to the opened stations. Finally, an undesirable facility location model is used to find the bike stations, which have the maximum distance from demand nodes, and to eliminate them. Results: In computational results, it is clearly seen that the proposed approaches set the potential bike station covering all demand points. They also provide different solutions for the campus planners. Conclusions: The methodology outlined in this study can provide university administrators with a useful insight into locations of stations, and in this way, it contributes significantly to future planning of bike-sharing systems.
AtıfScopus40WoS27OpenAlex38İncele - MakaleYayıncıda açık erişim2018Scopus SJRQ2Determination of pollution and heavy metal fractions in golden horn sediment sludge (Istanbul, Turkey)
Kanat, Gurdal; Ikizoglu, Bahar; Erguven, Gokhan Onder; Akgun, Berivan
In our study we studied pollution and heavy metal fractions in the Golden Horn (Istanbul, Turkey). This area has been exposed to domestic and industrial pollution for many years. Concentrations of Zn, Cr, Cu, Pb, Cd, and Ni heavy metals were determined in the study that was conducted to monitor the current state of pollution and changing conditions in the polluted estuary. Mean heavy metal concentrations were found as: Zn 70-260, Cr 26-110, Cu 70-135, Pb 8-50, Cd 0.1-2, and Ni 10-38 mg/kg. Results of the analysis showed that metal concentrations were usually low, indicating that the sediment was not too polluted in the present case. The range of ratios, different fractions of metal concentrations, and total metal concentrations in the samples were critical for potential toxicity and mobility of metals. Results of the analysis showed that heavy metal fractions in the sediment were usually found in residual forms. The values obtained in the study were also compared with the literature. It was found that surface sediments in the Golden Horn were less polluted than other areas. Establishment of sewer collectors and wastewater treatment plants has improved the heavy metal levels in the sediment.
AtıfScopus22WoS19OpenAlex23İncele
