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Determination of Natural Fundamental Period of Minarets by Using Artificial Neural Network and Assess the Impact of Different Materials on Their Seismic Vulnerability
(MDPI, 2023) Işık, Ercan; Ademovic, Naida; Harirchian, Ehsan; Avcil, Fatih; Büyüksaraç, Aydın; Hadzima-Nyarko, Marijana; Bülbül, Mehmet Akif; Işık, Mehmet Fatih; Antep, Barış
Abstract: Minarets are slender and tall structures that are built from different types of materials. Modern materials are also starting to be used in such structures with the recent developments in material technology. The seismic vulnerability and dynamic behavior of minarets can vary, depending on the material characteristics. Within this study’s scope, thirteen different material types used in minarets in Türkiye were chosen as variables. A sample minaret model was chosen as an example with nine different heights to reveal how material characteristic change affects seismic and dynamic behavior. Information and mechanical characteristics were given for all the material types. Natural fundamental periods, displacements, and base shear forces were attained from structural analyses for each selected material. The empirical period formula for each material is proposed using the obtained periods, depending on the different minaret heights taken into consideration. At the same time, fundamental natural periods for the first ten modes and 13 different types of materials used in the study were estimated with the established Artificial Neural Network (ANN) model. The real periods from the experimental analyses were compared with the values estimated by the ANN using fewer parameters, and 99% of the results were successful. In addition, time history analyses were used to evaluate the seismic performance of the minaret (three different materials were considered). In this specific case, the acceleration record from the 2011 Van (Eastern Turkiye) earthquake (Mw = 7.2) was taken into consideration. Performance levels were determined for the minaret according to the results obtained for each material. It has been concluded that material characteristics significantly affect the dynamic and seismic behavior of the minarets.
A Hybrid Artificial Neural Network-Particle Swarm Optimization Algorithm Model for the Determination of Target Displacements in Mid-Rise Regular Reinforced-Concrete Buildings
(MDPI, 2023) Işık, Mehmet Fatih; Avcil, Fatih; Harirchian,Ehsan; Akif Bülbül, Mehmet; Hadzima-Nyarko, Marijana; Işık, Ercan; İzol, Rabia; Radu, Dorin
Abstract: The realistic determination of damage estimation and building performance depends on target displacements in performance-based earthquake engineering. In this study, target displacements were obtained by performing pushover analysis for a sample reinforced-concrete building model, taking into account 60 different peak ground accelerations for each of the five different stories. Three different target displacements were obtained for damage estimation, such as damage limitation (DL), significant damage (SD), and near collapse (NC), obtained for each peak ground acceleration for five different numbers of stories, respectively. It aims to develop an artificial neural network (ANN)-based sustainable model to predict target displacements under different seismic risks for mid-rise regular reinforced-concrete buildings, which make up a large part of the existing building stock, using all the data obtained. For this purpose, a hybrid structure was established with the particle swarm optimization algorithm (PSO), and the network structure’s hyper parameters were optimized. Three different hybrid models were created in order to predict the target displacements most successfully. It was found that the ANN established with particles with the best position revealed by the hybrid models produced successful results in the calculation of the performance score. The created hybrid models produced 99% successful results in DL estimation, 99% in SD estimation, and 99% in NC estimation in determining target displacements in mid-rise regular reinforced-concrete buildings. The hybrid model also revealed which parameters should be used in ANN for estimating target displacements under different seismic risks.
Corrigendum for “Polymer-graphene hybrid stabilized ruthenium nanocatalysts for the dimethylamine-borane dehydrogenation at ambient conditions” [Journal of Molecular Liquids Volume 279, 1 April 2019, Pages 578-583; 10.1016/j.molliq.2019.02.003]
(Elsevier B.V., 2021) Şen, Betül; Aygün, Ayşenur; Şavk, Aysun; Duman, Sibel; Çalımlı, Mehmet Harbi; Bulut, Ela; Şen, Fatih
[No abstract available]
Observation of behavior of the Ahlat Gravestones (TURKEY) at seismic risk and their recognition by QR code
(TECHNO-PRESS, 2019) Işık, Ercan; Antep, Barış; Büyüksaraç, Aydın; Işık, Mehmet Fatih
Protection of cultural heritage and carrying it to the future are at the top of the significant topics of research and implementation in engineering in the 21st century. There are several historical structures in the district of Ahlat located in the east of Turkey on the Lake Van Basin that has harbored many civilizations. Some of such works are the gravestones that are found in the Ahlat Seljuk Cemetery, which is the oldest and largest cemetery in the district. This study firstly provides information about the Ahlat Seljuk Cemetery and the gravestones found in it. Observation-based structural analyses were carried out on these gravestones that are found in this area that are known to have belonged to different civilizations based on their physical and constructional characteristics. These stones were built out of Ahlat stone as single pieces. Information is provided on the damages that have occurred on the gravestones in time and their causes. In general, losses of mass, abrasions, separations, collapses and calcifications due to natural conditions, as well as vegetative formations, were observed in the gravestones. To provide an example of other gravestones within the context of the study, the gravestone that is known to belong to the person named Nureddin Ebu Hasan was selected. As a result of the modeling that was carried out for this gravestone by using the finite elements method, modal analyses were carried out. With these analyses, for the gravestone, period, effective mass participation rates and stress values were calculated. The stress values that were obtained in this study were compared to the material safety stress values that were obtained in previous studies. Additionally, QR code application was created for the gravestone that was selected as an example in the study, and information on this gravestone was transferred to an electronic environment. The QR code application includes different language options, visuals of the gravestone and information on the gravestone. The QR application was also supported with a video of the cemetery where the gravestone is located. With this application, access to information about gravestones will be possible by using tablets and smartphones. With a QR code to be created for each gravestone, these gravestones will obtain identity cards.
Tek makine sonsuz bara güç sisteminde sönümleme sargısı sabitinin rotor açısı kararlılığına etkisi
(Fırat Üniversitesi, 2014) Tozlu, Bilgehan; Sönmez, Fatih
Tek makine sonsuz bara güç sisteminde (SMIB) makinenin yani senkron generatörün sönümleme sargısı sabitinin rotor açısı kararlılığına etkisi çalışılmıştır. Sistem, salınım denklemi adı verilen denklemle modellenmiştir ve bilgisayar ortamında gerçekleştirilmiştir. Sistemin bütün değerleri sabit kabul edilerek sadece sönümleme sargısı sabiti değeri değiştirilmiş ve rotor açısı kararlılığının nasıl etkilendiği izlenmiştir. Bu çalışmada, SMIB güç sistemlerinde rotor açısı kararlılığının, senkron makinenin sönümleme sargısı sabitiyle nasıl değiştiği araştırılmıştır.
Tarımsal arazi sulama sistemlerinde mobil uygulamalar: örnek bir çalışma
(Gazi Üniversitesi, 2017) Işık, Mehmet Fatih; Yılmaz, Cemal; Işık, Ercan
Bu çalışmada, elmanın yetişme evresine bağlı olarak kurulan damlama sulama sistemlerinin mobil aygıtlardan kontrolünü ve izlenebilmesini sağlayan bir proje Çorum/Merkez' de başarılı bir şekilde uygulanmıştır. Klasik kontrol sistemi yerine günümüz teknolojisinin vazgeçilmez elemanları olan akıllı telefon üzerinden çalışabilen bir yapı oluşturulmuştur. Tarım arazisinde bulunan elma ağaçlarının kök kısımlarına yakın yerlere nem sensörleri yerleştirilmiştir. Bu sensörlerden alınan bilgilere göre sulama durumu çizelgesi oluşturulmuştur. Çalışmada bunun yanı sıra ürün yetişme evresine bağlı olarak da bir çizelgeleme oluşturulmuştur. Bu proje ile hem kullanılan su miktarında önemli bir avantaj sağlanmış hem de tarımsal süreçler için yeni bir izleme ve kontrol algoritması oluşturulmuştur.
A monitoring and control system integrated with smart phones for the efficient use of underground water resources in agricultural product growing
(Hitit University, 2017) Işık, Mehmet Fatih; Haboğlu, Mustafa Reşit; Işık, Ercan
Monitoring and control system is very important for crop development process in agriculture zones. A structure which is carried out based on the type of the product with the knowledge of temperature and humidity values of the agricultural land can contribute to the efficient use of underground water resources. Additionally, it can also contribute to the establishment of the administration of the land besides the economical contributions to the farmer. In this study, the values obtained by heat and humidity sensors which are placed in different locations of agricultural field are transmitted to a database by using a central operation unit. The water requirement based on the product is determined according to that database. Those values are transferred to the smart phones by using a Wi-Fi connection. A real time monitoring system is established on the smart phone. The energy supply of the system is obtained by solar cells. The design offers several advantages such as saving of the water, time and energy with the efficient use of underground water resources. Thus, by using clean energy, the design constitutes an environmental friendly system.
Farklı sıcaklık kontrol sistemlerinin termoelektrik tıp kitinin performansına etkisi
(Gazi Üniversitesi Mühendislik - Mimarlık Fakültesi, 2008) Ahıska, Raşit; Fidan, Uğur; Dişlitaş, Serkan
Kan, aşı, serum, ilaç v.b. tıbbi maddelerin bozulmadan saklanabilmesi için belirli sıcaklık koşullarında tutulması gerekmektedir. Bu amaca yönelik olarak geliştirilmiş olan Taşınabilir Termoelektrik Tıp Kiti hem birey hem de toplum sağlığı açısından büyük önem taşımaktadır. Dünya Sağlık Örgütü (WHO) tarafından belirlenen standartlara göre kanın depolanma sıcaklığı $2^{\circ}C$ ile $10^{\circ}C$ arasında olmalıdır. Bu çalışmada, bu standartlara uygun olarak ısıtma ve soğutma yapabilen Mikrodenetleyici Kontrollü Taşınabilir Termoelektrik Tıp Kiti cihazının elektronik kontrol devreleri geliştirilmiştir. Cihazın iç sıcaklık kontrolü iki farklı yöntemle yapılmış ve kontrol sonuçları karşılaştırılmıştır. Birinci yöntemde analog sensörlü, ikinci yöntemde ise dijital sensörlü devre kullanılarak cihazın sıcaklık kontrolü gerçekleştirilmiştir. Karşılaştırma sonuçlarına göre, Dijital Sıcaklık Sensörlü Kontrol Sistemi (DSSKS) ile yapılan soğutma ve ısıtma işleminin daha fazla enerji tasarrufu sağladığı görülmüştür.
Web based evaluation of earthquake damages for reinforced concrete buildings
(Techno Press, 2017) Işık, Ercan; Işık, Mehmet Fatih; Bülbül, Mehmet Akif
The first determination and assessment of the damages to structures after the earthquake is important for preventing increase in loss of life and property that may occur in later times. When rapid damage assessment is performed after an earthquake, damage assessment forms are generally used. The forms that are filled in the field are assessed in the office environment later. In this study, while the process of earthquake damage assessment was being carried out, the ready-made form was moved to web base and the data to be obtained in the field was transferred to the database by means of tablets and smart phones. Keeping earthquake damages in a database will contribute to the studies to be conducted on earthquake and the earthquake regulations to be prepared. Furthermore, emergency damage assessment will be performed faster and more reliably after the earthquake through this study. As the data transferred to the web base is accessible to different people, savings will be provided for both time and personnel. Furthermore, the assessment will have a healthier and scientific basis. In this study, exemplification was conducted for six different reinforced concrete buildings that were damaged during Van earthquake in October 23. With this study, damage assessment procedures can be completed as soon as possible. © 2017 Techno-Press, Ltd.
Precision irrigation system (PIS) using sensor network technology integrated with IOS/Android application
(MDPI AG, 2017) Işık, Mehmet Fatih; Sönmez, Yusuf; Yılmaz, Cemal; Özdemir, Veysel; Yılmaz, Ercan Nurcan
One of the most important factors for successful agricultural production is the irrigation system in place. In this study, a precision irrigation system, which takes advantage of the various phases of plant growth, was developed and implemented using the sensor network technology integrated with IOS/Android. The amount of water in the soil was measured via sensors that were placed on certain points of the area to be irrigated. These sensors were placed near the root of the product. Data from sensors was transmitted via Wi-Fi in real-time to a mobile phone based on IOS/Android. In the light of obtained data, the seasonal precision irrigation system was created depending on the amount of water required by the plants at each stage of their growth stage. The required energy of the system was provided by solar energy. The system can be controlled by smart phones, which increases the usability of the system. When design performance was analyzed, it was observed that some important advantages such as obtaining high efficiency with water, time and energy saving and reducing the workforce were ensured. Five separate laterals were used for the irrigation system. There were valves on each lateral, which realized the opening and closing process depending on the water need. A total of 16 humidity sensors were used in the irrigation system and the data from these sensors was transferred to the IOS/Android server via the programmable controller (PLC). The basic electrical equipment in the irrigation system was monitored and controlled via mobile devices. Control parameters were obtained by comparing the real values and reference values by a closed-loop system and determine the new working status of the irrigation system. © 2017 by the authors.
Design and implementation of real-time monitoring and control system supported with IOS/Android application for industrial furnaces
(John Wiley and Sons Inc., 2018) Yılmaz, Cemal; Yılmaz, Ercan Nurcan; Işık, Mehmet Fatih; Usalan, Mehmet Ali; Sönmez, Yusuf; Özdemir, Veysel
SCADA (supervisory control and data acquisition) systems have been used widely in the manufacturing process in parallel to the rapid advancement of technology in recent years. The quality of products in these systems depends on direct process monitoring and control. Therefore, in this study, a SCADA-based scale model is developed for real-time monitoring and control of an industrial furnace by using Android/IOS-based smartphones. To achieve the desired temperature in the furnace and to keep the energy saving constant, a PLC-based SCADA system was designed. In the designed system, the furnace temperature is measured continuously by sensors and the furnace voltage is set as analog in order to reach the desired temperature as soon as possible. Different PID parameters are used to achieve this aim. Thus, the product quality is increased and energy efficiency is achieved. © 2018 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. © 2018 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Modified ultrasound despeckling assessment index for the Field II simulated cyst image
(Institution of Engineering and Technology, 2017) Güngör, Murat Alparslan; Karagöz, İrfan
Various methods have been proposed to reduce speckle noise, which decreases image quality in ultrasound images. The Field II simulated cyst image consists of three classes and is used to compare a proposed despeckle filter with other wellknown filters. The ultrasound despeckling assessment index (USDSAI) is a metric used to evaluate the proposed despeckling filters for the cyst image. This metric should be used when different regions are properly defined. In this study, the authors first analysed the performance of USDSAI for the cyst image. Then, the authors modified the USDSAI by proposing a new metric for the background class of the cyst image and evaluated its performance. The results show that the authors' proposed metric has better performance than USDSAI. © 2017, The Institution of Engineering and Technology.
Servo control education tool for industrial applications
(2010) Işık, Mehmet Fatih; Coşkun, İsmail
In this study, a training set consisting of servo motors is designed to assist development of the students, especially who are in electrical, electronics and mechanical engineering, in industrial field. For this training set; three AC servo motors and one DC servo motor are used and four-axis control mechanism is generated. In order to control servo motors a special driving circuit is developed through which position and speed is controlled. These controls can be managed either via operating panel (touch panel) or via computer depending on user's purpose. In addition, a local network based training software is developed, which involves theoretical information regarding servo motors and allows testing opportunity and observing animations. Thus, a practical, functional and also economical training set allowing students both to learn and to perform many applications that they might be introduced with industrial field is developed.
AC chopper application and benefits of auxiliary windings for PSC motors
(2013) Işık, Mehmet Fatih; Güvenç, Uğur; Yanmaz, Hilmi
In this work, a novel driver circuit is designed for permanent split capacitor motors (PSC). With this driver circuit, semi-conductive technology is used in place of cumulative winding for this type of motors that are particularly used in kitchen exhaust fans. Developed circuit is controlled via PWM method. IGBT transistors are used for the power circuit. An optocoupler driver is designed and used in order to drive and trigger these IGBT transistors. Due to this reason, this work includes an electronic AC/AC chopper application that provides energy conservation and noise reduction by removing cumulative winding in currently used asynchronous motors with cumulative auxiliary winding stators and shaded pole motors.
Design and implementation of a training set for distributed system and mechatronic applications: project based learning
(Strojarski Facultet, 2016) Işık, Mehmet Fatih
Nowadays, with the development of information technology, real-time and reliable devices have been developed for users and system control. Commonly used ones are programmable logic controller and operator panels. Programming of these devices, learning the communication with the controller and the hardware installations have gained great importance especially for technical staff and engineering students. In this study, automation and control technique training sets were developed for the applications used widely in industrial applications. In the training sets, programmable logic controller (PLC) and human machine interface (HMI) were used for the control. With the training sets both automation education and control techniques such as P, PI, and PID are compared. At the same time, skills and logical programming abilities of the students studying in the training were attempted to be improved with this application. In order to measure and evaluate, 18 technical staff working in the industrial sector, 14 students studying automation engineering and eight students studying pre-license training, a group of 40 people in total was formed and performances were measured at the end of the training. © 2016, Strojarski Facultet. All rights reserved.
Design and implementation of real time monitoring and control system for distributed robotic systems supported with IOS/android application
(Strojarski Facultet, 2018) Işık, Mehmet Fatih; Haboğlu, Mustafa Reşit; Yılmaz, Cemal; Yılmaz, Ercan Nurcan
In this study, a real time monitoring and control of the working parameters of distributed robotic systems used in manufacturing processes is presented. Additionally, a fault diagnosis and protection system is developed in the control and monitoring system to prevent possible errors during the working process. Unlike the conventional monitoring and control systems, Android/IOS based smart phones and tablets are used besides SCADA and the process is supported by cameras. 3 different robotic systems are used in the study and electrical, electronic and mechanical prototypes are designed for each of them. Thus, a complete robotic system being able to perform real time monitoring and control for industrial manufacturing processes that is supported by smart phone applications and fault diagnosis and protection system is developed successfully. © 2018, Strojarski Facultet. All rights reserved.
Üç ayrık ölçüme dayalı parabol algoritması ile termoelektrik modülün Imax, Vmax ve Emax parametrelerinin belirlenmesi
(Gazi University, 2016) Dişlitaş, Serkan; Ahıska, Raşit
Termoelektrik (TE) modüllerin performansının belirlenmesi amacıyla çeşitli metotlar geliştirilmiştir. Bunlardan biri de Ahıska vd. tarafından geliştirilen sıcaklık, akım ve gerilim gibi kolaylıkla ölçülebilir parametreleri temel alan metottur. Bu metoda göre; TE modülün ısıl ve elektriksel performansını belirlemek için öncelikle Imax, Vmax ve Emax parametrelerinin belirlenmesi gerekmektedir. Klasik olarak TE modülün bu parametrelerini belirlemek için çok sayıda ölçüm yapılması gerekmektedir ve ayrıca her ölçümde ısıl dengenin sağlanması beklendiğinden bu yöntem aşırı zaman almaktadır. Bu çalışmada; TE modül ve sistemlerin Imax, Vmax ve Emax parametrelerinin daha hızlı bir şekilde belirlenmesi için üç ayrık ölçüm ve parabol hesaplarına dayanan yeni bir algoritma geliştirilmiştir. Geliştirilen yeni parabol algoritması, önceden geliştirilmiş olan Termoelektrik Performans Analiz Sistemi (TEPAS)’ne uyarlanmıştır. Yeni parabol algoritmasını temel alan test sisteminin performansının belirlenmesi amacıyla, Melcor CP1.4-127-10 model TE modül kullanılarak deneysel çalışmalar yapılmıştır. Geliştirilen yeni parabol algoritması yöntemi ile elde edilen parametrelerin klasik yönteme göre bağıl hata payları ??max için %0,3, Imax için %1, Vmax için %0,8 ve Emax için %2,9 olarak bulunmuştur. Sonuç olarak; TE modül ve sistemlerin Imax, Vmax ve Emax parametrelerinin parabol algoritmasına dayanan yeni yöntemle kısa sürede ve doğru olarak elde edilebileceği anlaşılmıştır.
Large bandwidth mode order converter by differential waveguides
(Optical Society of American (OSA), 2015) Öner, Bilgehan Barış; Üstün, Kadir; Kurt, Hamza; Okyay, Ali Kemal; Turhan Sayan, Gönül
In this article, we propose a large bandwidth mode-order converter design by dielectric waveguides with equal lengths but different cross-sectional areas. The efficient conversion between even and odd modes is verified by inducing required phase difference between the equal length waveguides of different widths. Y-junctions are composed of both tapered mode splitter and combiner to connect mono-mode waveguide to multi-mode waveguide. The converted mode profiles at the output port show that the device operates successfully at designed wavelengths with wide bandwidth. This study provides a novel technique to implement compact mode order converters and direction selective/sensitive photonic structures. © 2015 Optical Society of America.
Improvements on deinterleaving of radar pulses in dynamically varying signal environments
(Elsevier Inc., 2017) Gençol, Kenan; Kara, Ali; At, Nuray
An electronic support system receiver which is a passive receiver picks up an interleaved stream of pulses and extracts their pulse parameters. These parameters are sent to a deinterleaving subsystem which sorts them and forms pulse cells that each are assumed to belong to a specific emitter. In this paper, we develop a method for this task of deinterleaving of radar pulse sequences. For this aim, a novel pulse amplitude tracking algorithm is proposed for dynamically varying signal environments wherein radar parameters can change abruptly. This method particularly works for air-to-air engagements where pulse amplitude distortion due to channel effects can be considered negligible. Simulation results show that the proposed algorithm incorporated with a clustering algorithm improves deinterleaving of radar emitters that have agile pulse parameters such as airborne radars. © 2017 Elsevier Inc.
Efficient and broadband guided wave one-way mode-order conversion with theoretical and numerical analysis
(Optical Society of American (OSA), 2013) Üstün, Kadir; Kurt, Hamza
In this article, an efficient method of asymmetric conversion of guided modes is investigated. From a basic excitation consisting of (mainly) the lowest-order mode of the input multimode strip waveguide, we achieve a conversion efficiency of ~60% on average, in the forward propagation case, while the backward propagation is suppressed below 10%. The analytical formulation is based on electromagnetic wave theory with orthogonality relations. Affirmative results between the theoretical and numerical findings based on time and frequency domain analysis are observed. The results of this study will increase the ease of implementing an optical isolator if the breaking time-reversal symmetry could be achieved by nonlinear optics or magneto-optic configurations. © 2013 Optical Society of America.

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