Yazarlar
- Peker, Iskender(23)
- Araz, Onur(16)
- Erol, Ismail(15)
- Ar, Ilker Murat(12)
- Bayraktar, Alemdar(10)
- Seferoğlu, Mehmet Tevfik(10)
- Aydin, Metin Mutlu(9)
- Günaydin, Murat(9)
- Adanur, Süleyman(8)
- Altunişik, Ahmet Can(8)
- Basoglu, Mustafa Engin(8)
- Akyol, Mehmet(7)
- Yanarateş, Cağfer(7)
- Akpinar, Muhammet Vefa(6)
- Altan, Aytaç(6)
- Barut, Abdulkadir(6)
- Başoğlu, Mustafa Engin(6)
- Cakmak, Recep(6)
- Searcy, Cory(6)
- Çavdar, Özlem(6)
- Baki, Birdogan(5)
- Benli, Tolga(5)
- Gergin, Ramazan Eyüp(5)
- Kahya, Volkan(5)
- Kuzulugil, Kenan(5)
- Ozden, Talat(5)
- Pala, Fahrettin(5)
- Seferoğlu, Ayşegül Güneş(5)
- Sevim, Bariş(5)
- Yilmaz, Tekin(5)
- Adanur, S.(4)
- Adanur, Suleyman(4)
- Aksüt, Yavuz Selim(4)
- Altunisik, Ahmet Can(4)
- Aydin, Musa(4)
- Cakir, Mehmet Ali(4)
- Cavusoglu, Ibrahim(4)
- Coruh, Emine(4)
- Ercikdi, Bayram(4)
- Gunaydin, M.(4)
Yayınlar
- MakaleAçık Erişim2019Experimental and numerical studies on axially loaded reinforced square hollow section T-joints
Ozyurt, E.; Das, S.
This paper presents outcomes of experimental and numerical studies completed on unreinforced, collar plate reinforced and doubler plate reinforced Square Hollow Section (SHS)T-joints subjected to axial compressive loading on the brace member. A total of nine full-scale SHS T-joint specimens were fabricated and tested, in which six specimens were reinforced with collar plate and doubler plate. Non-linear finite element (FE)models were developed using finite element code, ABAQUS. Test data was used to validate these FE models. Subsequently, validated FE models were used to conduct an extensive parametric study to investigate the effect of various geometrical parameters of main members and reinforcement plates on the ultimate capacity of reinforced SHS T-joints. The parametric study found that use of both collar and doubler plate reinforcements significantly increase the ultimate capacity of SHS T-joints. Thickness of the reinforcing plate has a positive effect if the thickness of the reinforcing plate is limited to twice the thickness of the chord member. This study, however, found that the capacity of a reinforced SHS T-joint is not dependent on the type of reinforcing plate. The study concludes that the maximum capacity that can be achieved from a reinforced joint is about double the capacity of a similar unreinforced joint. It was found that the Eurocode EN 1993-1-8 overestimates the capacity of reinforced SHS T-joints. Therefore, a new design method for predicting the ultimate capacity of the collar plate and doubler plate reinforced SHS T-joints was developed and this new design method is presented in this paper.
- MakaleYayıncıda açık erişim2019Investigating the mechanical behavior of reclaimed asphalt pavement (RAP) bases in large scale test box
Seferoğlu, Ayşegül Güneş; Seferoğlu, Mehmet Tevfik; Akpinar, Muhammet Vefa
The objective of this research was to assess the elastic deformations and permanent strains of reclaimed asphalt pavement (RAP) material as a base layer when it is treated or untreated with pozzolanic cement under cyclic loads. A large-scale cyclic plate loading testing (CPLT) device was developed for studying the mechanical characteristics of pavement base layer. The laboratory test results indicated that when the RAP percentage of the mixtures increased, elastic deformations and permanent strains increased, but the opposite was true when the cement percentage increased. It was concluded that 100% RAP material can be used in base layers with 3% pozzolanic cement. The obtained deformation values and strain rates can be used as reasonable default design input values by pavement designers when using RAP as a substitute for natural aggregate base layers.
- MakaleYalnız künye2019A fuzzy logic embedded energy management software with multi-agent system for a stand-alone PV power plant
Ozden, T.; Kesler, S.; Okumus, H.I.
The worst scenario projected for an off-grid photovoltaic power system is the time interval that the solar irradiation amount is in short to supply the load throughout the day, and this situation is resulted in energy deficiency. Nowadays, an off-grid power generating system, which is designed to consider the worst scenario encountered only during a certain period of time, brings through big financial problems in terms of the initial installation costs. This study proposes a smart software to perform energy management considering users’ comfort and their criteria, which are taking some information from the agents communicating with the consumption units wirelessly and the battery agent. All loads and agents in this system are initially defined by the user according to the importance of the consumption loads such as critical, essential, significant, lesser, and insignificant loads. The proposed energy management software includes fuzzy logic-based decision maker to manage load suspension or put the suspended load into effect again according to the state of the sources. The total amount of consumption is kept less than the total existing energy so that the energy to be consumed by the critical loads is always provided. Considering the existing amount of energy and consumer preferences, the total amount of load units is maximized at each sampling step. The proposed system, which is attained without compromising the user comfort, enables more efficient energy consumption. Also, for supplying the critical loads in case of lack of energy is possible.
- MakaleYalnız künye2019An improved 0.8 V OC model based GMPPT technique for module level photovoltaic power optimizers
Basoglu, Mustafa Engin
Photovoltaic modules may experience some mismatching conditions that affect their available power capacity, causing inefficient maximum power point tracking (MPPT). Furthermore, their power-voltage (P-V) characteristic curve becomes a multi-peak structure in such conditions owing to the presence of bypass diodes included since every part of the modules may receive different solar irradiance. By taking into account these facts, this paper introduces an improved global MPPT technique comprising 0.8 V OC model and the limited and adaptive scan approach. The proposed technique eliminates the requirement of some threshold value, leading to unreliable operation which the classical 0.8 V OC model based studies suffer from. Furthermore, the tracking time has been reduced substantially with the proposed technique by limiting scanning interval. Performance of the proposed technique has been verified by experimental studies and compared with classical 0.8 V OC model and a full scanning technique, which have been already presented in the literature. Experimental results show that the proposed technique is simple to be implemented and it has better performance than classical 0.8 V OC model, full scanning, and perturb and observe algorithms. Therefore, the proposed technique is feasible and it can be used technically in module level distributed MPPT (DMPPT) applications.
- MakaleAçık Erişim2019A fast GMPPT algorithm based on PV characteristic for partial shading conditions
Başoğlu, Mustafa Engin
Photovoltaic (PV) modules experience some partial shading conditions (PSC) due to some various factors. In that kind of a condition, a few maximum power points (MPPs) possibly appear on the power-voltage (P-V) curve, which increases the tracking difficulties. It is known that maximum power point tracking (MPPT) may not be realized by hill climbing (HC) based conventional MPPT algorithms under PSCs. In this context, this paper presents a novel micro converter based algorithm that was developed by using P-V characteristics of PV modules. Unlike voltage or duty ratio scanning techniques, this paper introduces a new deciding method to determine the correct global MPP (GMPP) region. For this, the proposed method uses some duty ratios that were calculated corresponding to each MPP region. Thus, the initialization of duty ratio is done properly, which results in high tracking speed and accurate tracking of the GMPP. The other advantages of the proposed algorithm are structural simplicity, less computational burden, and ease of implementation with a basic microcontroller. The simulation results show that this algorithm has fast tracking capability and it manages to track GMPP for PSCs correctly, since it includes an artificial scanning procedure. Single ended primary inductance converter (SEPIC) is built in order to validate the proposed global maximum power point tracking (GMPPT) algorithm. The performance of the proposed GMPPT technique is verified by experimental studies. The results show that the proposed GMPPT technique is fast by up to five times than an adaptive full scanning strategy and improved IC algorithm. Furthermore, the proposed algorithm can be commercially used in micro converters, since it is compatible with small number of bypass diodes in a module.
- BildiriAçık Erişim2019Firm Selection Based on Logistics Risk Factors: A Multiple Criteria Decision Making Approach
Peker, Iskender; Korucuk, Selcuk; Baki, Birdogan
Logistics firms are exposed several domestic and global risks such as variability in demand, shipment damages, earthquakes, and terrorist attacks. The purpose of this study is to provide an approach for selecting a logistics firm based on logistics risk factors according to the manufacturing firms' perspectives. An analytical network process method is utilized to determine risk factors' importance levels and VIKOR method is used to select the logistics firm. The study results show that the most important logistics risk factors are customer and supplier, and the least risky logistic firm is B. It can be concluded that the proposed model enables managers to examine potential risks influencing their logistics activities and select the logistics firm having minimum risk.
- MakaleAçık Erişim2019Effects of pavement surface deformations on traffic flow
Aydin, Metin Mutlu; Topal, Ali
Pavement surface deformations have a significant effect on speed profile of vehicles and traffic flow conditions. These deformations limit driving properties and increase vehicle operation and maintenance costs. Additionally, they cause many problems such as accidents, slower movement speeds, capacity loss and severe discomfort states. There are many factors having an effect on road capacities and they vary according to different road and traffic flow conditions. In this study, it is aimed to investigate and develop models to estimate shockwave and bottleneck forming, capacity loss and speed reduction, which occurred on examined road links caused by pavement deformations. For the prediction of road capacity, flow–density (q–k) relationship, bottleneck and shockwave analysis methods were used. In the scope this study, deformed road links were divided into three sections; Section A – before deformation zone, Section B – deformation zone, and Section C – after deformation zone. All three sections were investigated and empirical results were obtained. According to analysis results, it was found that pavement surface deformations have a negative effect on the level of road service capa-bility. Obtained results also showed that there are significant reductions in capacity relatively by up to 44 and 26% would result from surface deformations on deformed lanes and non-deformed adjacent lanes.
- BildiriYalnız künye2019Module Level Global Maximum Power Point Tracking Strategy
Basoglu, Mustafa Engin
Partial shading of photovoltaic (PV) modules can occur at any time due to the obstacles such as chimney, tree, antenna, bird flock etc. Due to such obstacles, the entire surface of the PV module cannot receive an equal amount of irradiance; Therefore, PV modules cannot operate at its maximum power point (MPP). In this paper, an improved version of a 0.8VOC model based global maximum power point tracking (GMPPT) strategy has been proposed. Single ended primary inductance converter (SEPIC) is used as a power converter between PV module and load. Effectiveness of the proposed technique is presented by experimental studies with the comparison of a full scanning approach. Results of experimental studies show that proposed GMPPT strategy outperforms than full scanning based algorithm known.
- Derleme MakaleYalnız künye2019Automation in the Mining Industry: Review of Technology, Systems, Human Factors, and Political Risk
Rogers, W. Pratt; Kahraman, M. Mustafa; Drews, Frank A.; Powell, Kody; Haight, Joel M.; Wang, Yaxue; Baxla, Kritika; Sobalkar, Mohit
In the opinion of these authors, technology alone can never give an organization an edge over competitors or provide an industry step change. However, history has shown that technology applied with correct logistics and strategy makes a significant difference. Never has the minerals industry faced such daunting challenges and been in such need of a step change. Application of autonomous systems has been steadily increasing in the minerals industry. Automation technology has changed the mining value chain from exploration to mineral processing and refining. The future state will only see additional in-roads of automation into more processes and the whole system design. To better understand the near-future potential of automation, it is useful to explore and review the current state of automation in minerals development. A review of the state of automation research is given. The review will consider three critical areas: automation technology, system’s engineering and management processes around automation, and the role of human factors engineering in automated and semi-automated systems. The review ends with a discussion on the social and political risks of automation in terms of shared value and sustainable development.
- MakaleYalnız künye2019Exploring the value of using data: a case study of continuous improvement through data warehousing
Rogers, W. Pratt; Kahraman, M. Mustafa; Dessureault, Sean
The mining industry is adapting data-rich technology. Data management processes and infrastructure require additional investment which, can be difficult to justify. A valuation model for data management infrastructure would necessitate modelling the ‘use’ of data and quantifying the value and the likelihood of success of improvement initiatives. A model is presented which can assess the impacts of a data-driven initiative. The initiatives are shown to be the foundation of improved shift coordination resulting in significant and sustained operational improvements. This paper aims to illustrate the value of using data from source systems in mining operations.
- MakaleAçık Erişim2018Güneş Enerji Santralleri İçin Uygunluk Haritasının Elde Edilmesi: Bir Uygulama
Eroğlu, Hasan
Günümüzde güneş enerjisi, hayatımızın en önemli ve kaçınılmaz bir parçası haline gelen yenilenebilirenerji kaynaklarından (YEK) biridir. Her geçen gün dünya üzerindeki güneş enerji santrali (GES) sayısı katlanarakartmaktadır. Uygulama sayısı artan bu santrallerin çevresel, ekonomik ve sosyal açıdan en uygun yer tayinlerininyapılması oldukça büyük önem arz etmektedir. Bazı durumlarda santral kurulum yerini etkileyen bir önemli kriterinbile göz ardı edilmesi oldukça büyük zararlara neden olabilmektedir.Bu çalışmanın amacı, literatürdeki çalışmalarda eksikliği tespit edilen ve GES kurulumunu etkileyen kriterlerinönerilmesi, GES kurulumunu etkileyen tüm kriterlerin birbirlerine göre önem derecelendirme değerlerininbulunması ve kriterlere ait örnek bir çalışma alanında coğrafi veriler yardımıyla GES için uygunluk haritasının eldeedilmesidir. Kriterlerin ağırlık değerlerinin bulunmasında Bulanık Analitik Hiyerarşi Yöntemi (FAHP), verilerinişlenmesinde de coğrafi bilgi sistemleri kullanılmıştır. Bu amaçla 14 ana kriter ve bu kriterlere ait 70 alt kriterkonuyla ilgili uzman görüşleri, anketler ve literatürdeki çalışmalardan yararlanılarak belirlenmiştir. Çalışmanınsonunda, çalışma alanında GES’ler için en uygun, uygun ve izin verilmeyen yerlerin gösterildiği uygunluk haritasıelde edilmiştir. Bu çalışma, GES’lerin yer tespitinde daha doğru, çevresel, ekonomik ve sosyal GES santralikurulumunu netice veren geniş yelpazedeki kriterlerle araştırmacılara faydalı olacaktır.
- MakaleAçık Erişim2018Türk sürücülerin facebook sosyal paylaşım sitesini trafik bilgilendirme amacıyla kullanımı üzerine bir araştırma
Aydin, Metin Mutlu; Saplioglu, Meltem; Ünal, Ayşe
Teknolojik gelişmeler ve beraberinde getirdiği geniş iletişim olanakları, insanlarınçevrelerinde ortaya çıkan olayları algılama ve bu olaylar üzerine yorum yapabilmeolanağını artırmaktadır. Bilgiler, sosyal medya platformları ile hızlı ve evrenseldüzeyde yayılmakta; kısa süre içerisinde insanların bu içeriklere yorum yapıpkendi görüşlerini ifade edebilmelerine olanak sağlamaktadır. Sosyal medyanınbilgiyi kitlelere kolay ulaştırması ve grup kurma olanağı sunması; insanların belirlikonularda bu tür mecralarda yaygın şekilde örgütlenmesini sağlamaktadır. Buçalışma kapsamında, Ülkemizde ve Dünya’da yaygın olarak kullanılan sosyalmedya platformlarından Facebook’un trafikle ilgili birçok konuda sürücülertarafından kullanımı ve kentiçi ulaşımda etkileri incelenmeye çalışılmıştır. Buamaçla ilk aşamada Türkiye’de 81 ilde kurulan ve hızla yayılan Facebook “Trafik”gruplarının üye sayısı üzerinde etkili parametreler araştırılmıştır. Gruplardakigüncel kullanıcı sayıları tespit edilmiş; üye sayıları, incelenen illerle ilgiliparametrelerin etkisi, Adaptif Ağ Tabanlı Bulanık Çıkarım Sistemi (AdaptiveNetwork Fuzzy Inference System, ANFIS) ile modellenip tahmin edilmiştir. İkinciaşama olarak, grup sayısında yaşanan artışın trafik kazaları ve cezaları üzerindekietkisi korelasyon analizi ile incelenmiştir. Bağımlı (Facebook “Trafik” grup üyesayısı) ve bağımsız (eğitim düzeyi oranı, çalışan oranı, motorlu taşıt oranı veehliyetli sürücü oranı) değişkenler arasındaki ilişkiyi inceleyebilmek amacıylakorelasyon analizi yapılmış ve regresyonun açıklama gücü 0,77 olarak eldeedilmiştir ANFIS analizinde 62 il için belirlilik katsayısı R2=0,90 olarak tahminedilmiştir. İkinci aşamada, sosyal medya kullanımı ile trafik ceza sayılarında vetrafik kaza sayılarında bir değişim olup olmadığı araştırılmıştır; trafik ceza ve kazasayıları üzerindeki etki için daha detaylı mekânsal verilere ihtiyaç duyulduğu,gelecekte yapılacak çalışmalarda kaza olan kesimlerdeki sosyal paylaşımverilerinin toplanarak incelenmesi gerektiği görülmüştür.
- MakaleAçık Erişim2018Mavi Renklenme Zararının Tomrukların Endüstriyel İşlenme Özellikleri Üzerine Etkileri
Öztürk, Atakan; Komut, Osman
Mavi renklenme tomruk, kereste ve kullanım yerlerindeki malzemede estetik karakteristikler ve mekanik şok direncinde neden olduğudeğişimler dolayısıyla önemli ekonomik kayıplara yol açmaktadır. Diğer yandan, zarara maruz kalmış malzemede emprenye ve üstyüzey işlemlerindeki başarı oranının düşük olmasının tomruğun endüstriyel kullanım alanlarını önemli ölçüde sınırlandırdığıbilinmektedir. Bu çalışma mavi renklenme zararının, tomruk işleyen orman endüstri işletmeleri üretim süreci üzerindeki etkilerini veneden olduğu kayıpları belirlemeyi amaçlamıştır. Araştırma, Gümüşhane ilinde Sarıçam tomruğu işleyen toplam 9 küçük ve orta ölçeklikereste üretim işletmesinde gerçekleştirilmiştir. Çalışmada, mavi renklenme zararının boyutu tomruk toplam hacmine oranlanarakdeğerlendirilmiştir. Diğer yandan, inşaat ve doğrama sektörlerine yönelik üretim gerçekleştiren işletmeler arasında, mavileşmesonucu oluşan tahribat yönünden karşılaştırmalar yapılmıştır. Çalışma sonucunda, mavi renklenme tahribatında hacmen zarara maruzkalma oranının diri odun genişliği, tomruk boy ve çap değişkenlerine bağlı olmak üzere %32-84 arasında değiştiği belirlenmiştir.Ayrıca, inşaat ve doğrama sektörlerine yönelik kereste üretimi yapan işletmeler arasında tomruk enine kesit yüzeyindeki mavileşmişalan genişliği ve bozuk hacim oranı değişkenlerine göre istatistiksel düzeyde anlamlı farklılıklar bulunduğu (p<0,05) tespit edilmiştir.Diğer yandan, inşaat sektörüne yönelik üretim yapan kereste işletmelerinde mavi renklenme zararının göz ardı edildiği görülmüştür.Doğrama sektörüne yönelik üretim yapan işletmelerde ise malzemenin görsel niteliklerinin iyileştirilmesi amacıyla mavileşmiş kısmınuzaklaştırıldığı, ancak bu işlem dolayısıyla ilave enerji ve işgücü maliyetlerinin oluştuğu tespit edilmiştir.
- MakaleAçık Erişim2018Effects of manufacturing type on control performance of multiple tunedmass dampers under harmonic excitation
Kahya, Volkan; Araz, O.
Using different optimization techniques, the optimum characteristics of multiple tuned mass dampers (MTMD) for reducing the dynamic response of primary structure due to various excitations are studied by many researchers. In this paper, the five practical MTMD models are considered which consist of different combinations of the mass, damping, stiffness coefficient and damping ratio in the MTMD. The criteria selected for the optimality is the minimization of the maximum value of the displacement dynamic magnification factor (DMF) of the primary structure with the MTMD system under external harmonic excitation. The optimum parameters of the MTMD systems are investigated using Sequential Quadratic Programming (SQP). Results obtained illustrate that the optimum MTMD-1 and MTMD-4 have nearly the same control performance and provide higher effectiveness than all the other types of MTMDs of the same mass ratio in reducing the displacement response of primary structure. Finally, a robustness analysis of optimally designed MTMD systems to investigate their performance under errors in the tuned frequencies is also performed in detail.
- MakaleYalnız künye2018Automated Model Updating of Historical Masonry Structures Based on Ambient Vibration Measurements
Altunisik, Ahmet Can; Okur, Fatih Yesevi; Genç, Ali Fuat; Günaydin, Murat; Adanur, Suleyman
Finite-element (FE) model updating is a very effective procedure for determining the uncertainty parameters in a structural model and minimize differences between experimentally and analytically identified dynamic characteristics. This procedure can be practiced with manual and global/local automatic model updating procedures. Automatic model updating is very popular because of its applicability to all kinds of engineering structures to minimize differences, and its damage localization and structural health monitoring. This paper considers a historical masonry bastion to obtain its dynamic characteristics numerically with the finite-element method and experimentally with ambient vibration tests (AVTs). Sensitivity analyses for the uncertainty parameters and manual and automated model updating to minimize differences are also performed. A castle bastion located in Trabzon, Turkey is selected as an application. The FE model of structure is developed in commercial software. The first three natural frequencies are obtained between 5 and 10Hz, and AVTs are performed under natural excitation using enhanced frequency domain decomposition (EFDD) and subspace structural identification (SSI) techniques. The first three natural frequencies are obtained between 4 and 7Hz. The comparison of analytically and experimentally identified dynamic characteristics shows a close agreement between mode shapes, but 26% difference in natural frequencies. To minimize the difference, the FE model of the bastion is updated using manual and global/local automated updating, changing its material properties of Young's modulus and material density. The maximum differences are reduced from 27 to 3% with manual updating, and to 0.02% with automated model updating.
- MakaleYalnız künye2018Hybrid global maximum power point tracking approach for photovoltaic power optimisers
Basoglu, Mustafa Engin; Çakir, Bekir
A new hybrid global maximum power point (MPP) tracking (MPPT) method is introduced in this study by using an improved 0.8 VOC model-based algorithm containing a smart power scanning procedure which is based on the sign of a change of photovoltaic (PV) module power. By courtesy of this procedure, the global MPP is determined effectively and within a small scanning time interval. The effectiveness of the proposed global MPPT algorithm has been validated by experimental studies. One of the buck-boost converter types, a single-ended primary inductance converter was implemented in this context. Experimental results show that tracking efficiency in the proposed algorithm is very satisfactory since blind scanning is prevented. Furthermore, it is presented in the experimental results that tracking efficiency is bigger in the proposed shading detection approach by up to 11.29% than the other technique which monitors voltage and current variations. In addition, there are no high software and hardware burdens which make this MPPT algorithm applicable especially in the smart alternating current module, module-integrated converters, PV power optimisers, and module level distributed MPPT applications.
- MakaleAçık Erişim2018Investigation of the Effect of Recycled Asphalt Pavement Material on Permeability and Bearing Capacity in the Base Layer
Seferoǧlu, Ayşegül Güneş; Seferoǧlu, Mehmet Tevfik; Akpinar, Muhammet Vefa
The purpose of this research was to investigate the effects of recycled asphalt pavement (RAP) and cement content on the permeability and bearing capacity characteristics of aggregate base courses. Mixtures containing untreated RAP ranging between 0 and 100 percent and 1, 2, and 3% cement-treated RAP were subjected to laboratory tests (bitumen content, sieve analysis, modified proctor, soaked California bearing ratio (CBR), and constant-level permeability tests). The results showed that, as the RAP percentage in the mixture increased, CBR values decreased considerably. Moreover, there is a linear increase in the CBR values with cement treatment. Optimum moisture contents (OMC) and maximum dry densities (MDD) showed a decreasing trend. Increasing the cement percentages in 100% RAP blend increases the OMC and MDD values. The permeability of RAP showed a decrease as the percentage of RAP and cement increased in blends. The study showed that the CBR value of the 20% RAP blend is also obtained in the 100% RAP/3% cement-treated blend. Thus, it has been understood that cement is a suitable material in order to increase the use of RAP. In addition, the increase in the percentage of RAP and cement made the base course more impermeable.
- MakaleYayıncıda açık erişim2018Choosing safe and suitable bicycle routes to integrate cycling and public transport systems
Saplıoğlu, M.; Aydın, M.M.
Bicycle utilization has become an important transportation mode in various cities during the past decade. It has brought a rapid growth as an important transport mode in many countries by providing several benefits for traffic, health and cost. However, the growing in bicycle utilization demand causes many problems such as safety, effectiveness etc. For this reason, other effective parameters on urban transport should be considered when planning new safe bicycle paths in the spatial platform. In this study, it was aimed to examine all these negative and positive effective parameters on safety and choice while integrating cycling with a public transport (bus link) system. To determine effective parameters on route choice, a Questionnaire Survey (QS) was carried out on 460 participants who are cycling for a long time in Isparta City/Turkey. It was obtained from the QS that Accident Prone Areas (APA) are the most important factor on cycling and public transport integration. The other parameters are determined as Bus Lane (BL), Road Side Car Park (RSCP), Bicycle Parks (BP), Road Grade (RG), Signalization (S), Traffic Capacity (TC), Connected Bike Lane (CBL) and Separated Bike Lane (SBL) according to their importance. In order to determine safer and serviceable bicycle routes selection problem, accident-prone locations (using Accident Reports and Geographic Information Systems-GIS), bus lines and survey data has been used in GIS. Also, a multi-criteria decision making approach Analytic Hierarchy Process (AHP) method is implemented to analyze survey data and decide effective parameters on safer and serviceable bicycle routes. It was found that safer and serviceable bicycle routes can be determined by the utilization of QS, GIS and AHP methods with together. Also, it was concluded that Accident Prone Areas, Bus Lanes and Road Side Car Parks are the most important factors while integrating cycling with a public transport system.
- MakaleYalnız künye2018Experimental study on cement-treated and untreated RAP blended bases: Cyclic plate loading test
Seferoğlu, Ayşegül Güneş; Seferoğlu, Mehmet Tevfik; Akpinar, Muhammet Vefa
The asphalt surrounding the reclaimed asphalt pavement (RAP) aggregates decrease the performance characteristics of road layers. RAP material increases the permanent deformation potential of road layers under the traffic load. In this study, the performances of RAP-VA (Virgin aggregate) mixtures was tested using cyclic plate loading test by adding pozzolanic cement into mixtures in order to use RAP material at the rate of 100% and to minimize the permanent deformation in plant-mix base courses (PBC). The permanent surface deformations of base course were measured at different points throughout 100 loading cycles and all of the measurements were compared to that of base course prepared from 100% VA. The effect of RAP/cement rate of mixtures on the permanent deformations was examined and it was determined that the increase in RAP rate increased the permanent deformations but cement significantly decreased it. Moreover, considering the material costs of mixtures, the cost analysis was performed and the profit margins that using RAP and cement offers to constructors were computed.
- MakaleAçık Erişim2018Sensitivity-Based Model Updating of Building Frames using Modal Test Data
Altunişik, Ahmet Can; Karahasan, Olguhan Şevket; Genç, Ali Fuat; Okur, Fatih Yesevi; Günaydin, Murat; Adanur, Süleyman
Model updating is of significant importance in the actual analyses of real structures. The differences between experimental and numerical dynamic characteristics can be minimized by means of this procedure. This procedure can be carried out using two approaches, namely, the manual model updating and the global or local automated model updating. The local model updating is a convenient tool for all kind of structures capable of minimizing the differences mentioned previously nearly to zero and also of identifying the damage locations and monitoring structural integrity. In this way, current realistic behavior of structures can be represented by updated finite element models. This paper describes a Reinforced Concrete (RC) frame model, its ambient vibration testing, finite element modeling and sensitivity-based automated model updating. The RC frame is of ½ geometric scale with two floors and two bays in the longitudinal direction. It was built and then subjected to ambient vibration tests to determine experimentally their dynamic characteristics. Additionally, the finite element computer program ANSYS was used to determine its initial numerical dynamic characteristics. The experimental and numerical results were compared resulting in maximum differences of 38.38% between them. To minimize these differences, the finite element model was updated using the global and local automated approach using a sensitivity-based analyses with some uncertain parameters. The differences were finally reduced to 4.4% and 0.21% by the global and the local automated model updatings, respectively. It is concluded that sensitivity-based automated updating is a very effective procedure to obtain the updated finite element model which can reflect the current behavior of a structure.
