Yazarlar
- Can, Erol(29)
- Kumbasaroglu, Atila(17)
- Yalciner, Hakan(17)
- Bayata, Halim Ferit(14)
- Ting, Naim Suleyman(14)
- Katipoğlu, Okan Mert(13)
- Bayrak, Osman Ünsal(12)
- Sahin, Yakup(12)
- Turan, Ahmet İhsan(9)
- Baş, Fatih İrfan(8)
- Destek, Mehmet Akif(8)
- Manga, Müge(8)
- Çolak, Muhammed Ali(8)
- Bulut, H. Alperen(6)
- Manga, Muge(6)
- Tastimur, Canan(6)
- Akin, Erhan(5)
- Akoğuz, Harun(5)
- Akın, Fatih(5)
- Balli, Esra(5)
- Dede, Tayfun(5)
- Sarıgöl, Metin(5)
- Sarıçiçek, İnci(5)
- Aka, Salih(4)
- Ayasun, Saffet(4)
- Ayaz, Yaşar(4)
- Celik, Alper(4)
- Demirci, Oğuz Kürşat(4)
- Demirel, Soner(4)
- Kalkan, Orhan(4)
- Keleş, Ömer Faruk(4)
- Tortum, Ahmet(4)
- Tuysuz, Suat(4)
- Yavuz, Selahattin(4)
- Yazici, Ahmet(4)
- Yazıcı, Ahmet(4)
- Yesilyurt, Huseyin(4)
- Yılmaz, Mehmet(4)
- Çabuk, Umut Can(4)
- Özkan, Kemal(4)
Yayınlar
- ArticleYalnız künye2017Exergoeconomic analysis and multi objective optimization of a solar based integrated energy system for hydrogen production
Khanmohammadi, S.; Heidarnejad, P.; Javani, N.; Ganjehsarabi, H.
In the current study, an integrated renewable based energy system consisting of a solar flat plate collector is employed to generate electricity while providing cooling load and hydrogen. A parametric study is carried out in order to determine the main design parameters and their effects on the objective functions of the system. The outlet temperature of generator, inlet temperature to organic Rankine cycle turbine, solar irradiation intensity (I), collector mass flow rate (m˙col) and flat plate collector area (AP) are considered as five decision variables. The results of parametric study show that the variation of collector mass flow rate between 3 kg/s and 8 kg/s has different effects on exergy efficiency and total cost rate of the system. In addition, the result shows that increment of inlet temperature to the ORC evaporator has a negative effect on cooling capacity of the system. It can lead to a decrease the cooling capacity from 44.29 kW to 22.6 kW, while the electricity generation and hydrogen production rate of the system increase. Therefore, a multi objective optimization is performed in order to introduce the optimal design conditions based on an evolutionary genetic algorithm. Optimization results show that exergy efficiency of the system can be enhanced from 1.72% to 3.2% and simultaneously the cost of the system can increase from 19.59 $/h to 22.28 $/h in optimal states.
RDL Kalıcı Kaydıİncele - ArticleYalnız künye2017A study on mechanical properties of polymer concrete containing electronic plastic waste
Bulut, H. Alperen; Şahin, Remzi
It is aimed to research the effects of electronic plastic waste (e-plastic) on the mechanical properties of polymer concrete. E-plastic was used as a part of the filling materials (quartz sand and gravel) to obtain polymer concrete in this study. Unsaturated polyester resin material has been chosen as the polymer material and used as binder in polymer concrete production. Resin/filling material ratio has been determined as 10–90%, 15–85% and 20–80%, e-plastic/filling material ratio has been decided to be 0%, 5%, 15% and 25%. 28-Day of axial compressive, flexural and splitting tensile strength values of the test samples were evaluated. The increase in the ratio of resin, increases the compressive strength while it does not cause a dramatic increase or decrease in the flexural and splitting tensile strength. Compressive, flexural and splitting tensile strength values decrease as the ratio of e-plastic increases. On the other hand, electronic plastic waste increases the polymer concrete's ductility. Experimental study shows that ideal resin ratio and ideal e-plastic ratio values are 15% and 5%, respectively.
RDL Kalıcı Kaydıİncele - Conference ObjectYalnız künye2016Energy and exergy analyses of a solar assisted combined power and cooling cycle
Ganjehsarabi, Hadi; Asker, Mustafa; Seyhan, Aslihan Kurnuc
In this study, a thermodynamic analysis of a solar assisted Rankine-Goswami integrated cycle is carried out for a range from 230 to 240 MW sizes. To illustrate the performance characteristics of these integrated cycle, an exergy analysis is conducted to pinpoint the losses due to internal and external irreversibilities of each component. In addition, the effect of design parameter such as condenser pressure on the performance of the integrated cycle is examined. The results shows that the variation of condenser pressure from 4 kPa to 24 kPa greatly reduces the exergy efficiency of the system. Moreover, it is found the exergy efficiency of standard solar assisted Rankine cycle case is 42.8% whereas the exergy efficiency of solar Rankine-Goswami multigeneration system is 47.03%.
RDL Kalıcı Kaydıİncele - ArticleAçık Erişim2016PID and fuzzy controlling three phase asynchronous machine by low level dc source three phase inverter; [PID i neizrazito upravljanje trofaznim asinhronim motorom pomoću trofaznog izmjenjivača slabe istosmjerne struje]
Can, Erol; Sayan, H. Hüseyin
In this study, a three-phase asynchronous motor driven by a broad-based system is described. So, mathematical model of converter, sinus pulse width modulation for the three phase inverter, and mathematical model of three-phase asynchronous motor have to be utilized in order to establish the system. After creating such a system, Fuzzy Logic and PID controllers are focused in order to get satisfactory results which are short settling time of rotor speed, low harmonic and short settling time of high phase current. Created mathematical models are run at the MATLAB Simulink. Direct voltage is applied to converter input. This voltage is represented by a renewable energy source that could be obtained from solar energy source. The direct voltage is lower than the peak of the alternating voltage. The alternating voltage is obtained from output of the inverter to drive the induction motor. Firstly, resistive (R) and inductive (L) loads are driven. Secondly, three-phase asynchronous motor (ASM) is driven with the low direct voltage. After that, simulation results are given in order to demonstrate performance and effectiveness of the proposed system.
RDL Kalıcı Kaydıİncele - ArticleAçık Erişim2016SSPWM three phase inverter design and experimented on unbalanced loads; [Konstrukcija SSPWM trofaznog izmjenjivača i primjena kod nestabilnih potrošača]
Can, Erol; Sayan, H. Hüseyin
A circuit-oriented approach for the analysis of pulse width modulation (PWM) three phase inverter is presented in order to run unbalanced loads in low nonlinear effects as harmonics. This method uses the identification of a six switch nonlinear device, which consists of only the active and passive switches in three phase inverter. When operating characteristics of the MOSFET switch are determined according to step-sinus pulse width modulation method, an average equivalent inverter model can be formed. After that, SSPWM technique is used to drive unbalanced loads in order to compare with common pulse width modulation (PWM) running unstable loads. First, the inverter load of resistive (R) and inductive (L) are performed at the MATLAB Simulink so that by PWM technique could be shown the reducing effect of the harmonic on loads. After that, the system is implemented by real elements as MOSFETs, PIC17F877A, PC 817 phototransitors.
RDL Kalıcı Kaydıİncele - Conference ObjectYalnız künye2016ARTMoS: An RFID tag mobility scheme with IPv6 and DNS
Cabuk, Umut Can; Jacobsen, Rune Hylsberg; Dalkilic, Gokhan; Yuldirim, T.; Cosulschi, M.; Florea, A.M.; Badica, C.; Koprinkova-Hristova, P.
It was long time ago, when the Internet was a basic network used for data and information sharing. The evolutionary process of the Internet started with connecting people and then with the increasing popularity of it and with the emerging concept of smart systems, device-To-device communications within smart systems dawned. And now; by taking the advantage of another emerging concept: mobility, we are able to connect any object to that network and build the Internet of Things. In this article, we propose, implement, and discuss the outcomes of such a system, which uses RFID tags to identify objects, a reader to detect the tags, a computer platform to connect them to the next generation IPv6 Internet and a DNS server to provide mobility and accessibility.
RDL Kalıcı Kaydıİncele - Book ChapterYalnız künye2016Design optimization of a wind turbine using artificial intelligence
Jayabalan, Jagan; Yildirim, Dalkilic; Kim, Dookie; Samui, Pijush
This chapter examines the capability of Support Vector Machine (SVM), Relevance Vector Machine (RVM) and Genetic Programming (GP) for the optimal design of wind turbine. The excellent design has been influenced by various factors, such as profile of the blade, number of blades, power factor and tip speed ratio. The key to design a wind turbine is to Assessing the optimal tip speed ratio (TSR) is the key for designing the wind turbine. This chapter handles the Artificial Intelligence techniques in predicting the optimal TSR and the power factor based on the parameters engaged for NACA 4415 and LS-1 profile types with 3 and 4 blades. The organized machine learning framework is anticipated to be lucrative than the traditional way in foretelling the TSR and power factor. The machine learning models are then compared with the existing Neural Network model and the pros and cons of the various models are inferred from the results.
RDL Kalıcı Kaydıİncele - ArticleAçık Erişim2015Seismic Performance Assessment of a Corroded 50-Year-Old Reinforced Concrete Building
Yalciner, Hakan; Sensoy, Serhan; Eren, Ozgur
Deterioration due to corrosion becomes a more serious problem when future earthquakes with unpredicted intensity and time are considered. Therefore, the prediction of performance levels of corroded reinforced concrete structures is important to prevent serious premature damage. In this study, a corroded, 50-year-old high school building was analyzed by considering corrosion effects and is presented here as a case study. The relevant data obtained from the structure were used to predict its performance level for different time periods by combining two major effects of corrosion. Deformation due to bond-slip relationships and loss in cross-sectional areas of reinforcement bars were examined as a function of corrosion rate for five corrosion levels. Plastic hinges were defined as a consequence of corrosion effects, and they were used to perform nonlinear push-over analyses. Incremental dynamic analysis was then performed for 20 individual earthquake ground motion records to predict the structure's time-dependent performance levels as a function of corrosion rate. Results showed that corrosion had a serious effect on the performance levels of the school building considered in this study by decreasing bond strength. (C) 2015 American Society of Civil Engineers.
RDL Kalıcı Kaydıİncele - ArticleAçık Erişim2015The factors affecting the quality of in-service training on information and communication technologies
Yildirim, Önder; Kurşun, Engin; Göktaş, Yüksel
In-service training (IST) has an important role in order to provide innovations, reforms and improvements as well as necessary training programs to the teachers and facilitate the changes. The aim of this study is to identify the underlying factors that affect the quality of the training by examining the scientific studies (theses and articles) conducted on IST related to information and communication technologies (ICT). In the study, meta-synthesis method (thematic content analysis), which is one of the content analysis methods has been employed. The scientific studies related to the subject have been reached by the databases that include academic publications in the fields of social science and education. The results and suggestions parts of 51 publications, which are identified as related to the subject from the databases, have been formed the findings of this study. The data obtained have been analyzed by using the PIE model which stands for planning, implementation and evaluation. The technical infrastructure, proper and ready environment, scheduling ISTs at available times of trainees, using distance education methods and evaluation of the trainees at the end of the course are the main factors that present the quality of IST within the scope of ICT.
RDL Kalıcı Kaydıİncele - ArticleAçık Erişim2014Structural response to blast loading: The effects of corrosion on reinforced concrete structures
Yalciner, Hakan
Structural blast design has become a necessary part of the design with increasing terrorist attacks. Terrorist attacks are not the one to make the structures important against blast loading where other explosions such as high gas explosions also take an important place in structural safety. The main objective of this study was to verify the structural performance levels under the impact of different blast loading scenarios. The blast loads were represented by using triangular pulse for single degree of freedom system. The effect of blast load on both corroded and uncorroded reinforced concrete buildings was examined for different explosion distances. Modified plastic hinge properties were used to ensure the effects of corrosion. The results indicated that explosion distance and concrete strength were key parameters to define the performance of the structures against blast loading.
RDL Kalıcı Kaydıİncele - Conference ObjectYalnız künye2014An investigation of government and private hospitals' supply chain management
Polater, Abdussamet; Bektas, Cetin; Demirdogen, Serkan
Health services have exceptional importance in service industries since they serve human health and public welfare. Successful health services are required to be of high quality, efficient and consistent, while economics principles are taken into account. Supply chain management is considered as a mean to attain all of these conditions. Considering that logistics management is an important function in hospital management, this paper examines the potential reasons for logistical differences between government and private hospitals in Erzincan, Turkey. There are different variables that may cause these differences such as: a logistics department's area of responsibility, like procurement, goods receiving, internal distribution, and information technology systems; the quantity of pharmaceutical products distributed; the level of corporation among hospitals and their suppliers; the previous and future plans of hospitals in developing the logistics management. Therefore, this study provides an appraisal of healthcare supply chain management by underlining the areas of improvements and determining obstacles for applying logistics management practices.
RDL Kalıcı Kaydıİncele - Book ChapterYalnız künye2014Modeling of wind speed profile using soft computing techniques
Samui, Pijush; Dalkiliç, Yildirim
This chapter examines the capability of three soft computing techniques (Genetic Programming [GP], Support Vector Machine [SVM], and Multivariate Adaptive Regression Spline [MARS]) for prediction of wind speed in Nigeria. Latitude, longitude, altitude, and the month of the year have been used as inputs of GP, RVM, and MARS models. The output of GP, SVM, and MARS is wind speed. GP, SVM, and MARS have been used as regression techniques. To develop GP, MARS, and SVM, the datasets have been divided into the following two groups: 1) Training Dataset - this is required to develop GP, MPMR, and RVM models. This study uses 18 stations' data as a training dataset. 2) Testing Dataset - this is required to verify the developed GP, MPMR, and RVM models. The remaining 10 stations data have been used as testing dataset. Radial basis function has been used as kernel functions for SVM. A detailed comparative study between the developed GP, SVM, and MARS models is performed in this chapter.
RDL Kalıcı Kaydıİncele - Conference ObjectAçık Erişim2008Artificial immune inspired fault detection algorithm based on fuzzy clustering and genetic algorithm methods
Aydin, Ilhan; Karakose, Mehmet; Akin, Erhan
Early detection and diagnosis of incipient faults are desired for online condition monitoring and improved operational efficiency of induction motors. In this study, an artificial immune inspired fault detection algorithm based on fuzzy clustering and genetic algorithm is developed to detect broken rotor bar and broken connector faults in induction motors. The proposed algorithm uses only one phase stator current as input without the need for any other signals. The new feature signal called envelop is obtained by using Hilbert transform. This signal is examined in a phase space that is constructed by nonlinear time series analysis method. The artificial immune algorithm called negative selection is used to detect faults. The cluster centers of healthy motor phase space are obtained by fuzzy clustering method and they are taken as self patterns. The detectors of negative selection are generated by genetic algorithm. Self patterns generated by fuzzy clustering speed up the training stage of our algorithm and only small numbers of detectors are sufficient to detect any faults of induction motor. Results have demonstrated that the proposed system is able to detect faults in a three phase induction motor, successfully.
RDL Kalıcı Kaydıİncele - Conference ObjectAçık Erişim2007A simple and efficient method for fault diagnosis using time series data mining
Aydin, I.; Karaköse, M.; Akin, E.
Early detection and diagnosis of incipient faults is desirable for online condition evaluation and improved operational efficiency of induction motors. A classification technique based on time series data mining is developed to detect broken rotor bar faults in induction motors. The proposed algorithm uses only stator phase currents as input without the need for any other signals. The stator phase currents are transformed to park's vector components and a new feature vector is constituted by using these components. The phase space of constituted feature vector is constructed according to determined time delay and embedding dimension for each motor conditions. Each motor condition is separated to two clusters by using fuzzy c-means clustering algorithm. The center points of these clusters are saved for test phase. A Gaussian membership function is used for that a point is the degree of belonging to a cluster. The current signals of a three phase induction motor are derived an actual experimental setup. A healthy induction motor and one, two and three broken rotor bar faults are classified under four different operation speed. Experimental results show the strength of the proposed method.
RDL Kalıcı Kaydıİncele - Conference ObjectAçık Erişim2007Artificial immune based support vector machine algorithm for fault diagnosis of induction motors
Aydin, I.; Karaköse, M.; Akin, E.; Ertan, HB; Uctug, Y
The use of induction motors is widespread in industry. Many researchers have studied the condition monitoring and detecting the faults of induction motors at an early stage. Early detection of motor faults results in fast unscheduled maintenance. In this study, a new artificial immune based support vector machine algorithm is proposed for fault diagnosis of induction motors. Support vector machines (SVMs) have become one of the most popular classification methods in soft computing, recently. However, classification accuracy depends on kernel and penalty parameters. Artificial immune system has abilities of learning, memory and self adaptive control. The kernel and penalizes parameters of support vector machine are tuned using artificial immune system. The training data of support vector machine are extracted from three phase motor current. The new feature vector is constructed based on park's vector approach. The phase space of this feature vector is constructed using nonlinear time series analysis. Broken rotor bar and stator short circuit faults are classified in combined phase space using support vector machines. The experimental data are taken from a three phase induction motor. One, two and three broken rotor bar faults and 10% short circuit of stator faults are detected successfully.
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