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Displacements And Kinematics Of The February 1, 1944 Gerede Earthquake (North Anatolian Fault System, Turkey): Geodetic And Geological Constraints, Mehmet Emi̇n Ayhan, Ali̇ Koçyi̇ği̇t
Displacements And Kinematics Of The February 1, 1944 Gerede Earthquake (North Anatolian Fault System, Turkey): Geodetic And Geological Constraints, Mehmet Emi̇n Ayhan, Ali̇ Koçyi̇ği̇t
Turkish Journal of Earth Sciences
The North Anatolian Fault System (NAFS) is an approximately 2-110-km-wide, 1600-km-long right-lateral intra-continental transform fault boundary between the Anatolian platelet and the Eurasian plate. The Gerede fault zone is one of the major active structures in the western section of the NAFS. It is a 1-9-km-wide, 325-km-long and ENE-trending dextral strike-slip fault zone, with a total accumulated offset since its initiation (Late Pliocene) of about 43 km. This offset indicates an average geological slip rate of 16.5 mm/yr. The 1 February 1944 Gerede earthquake occurred within the Gerede fault zone. Based on recent field geological mapping of the rupture traces …
Production Of (S)-2'-Fluorophenylethan-1-Ol And (S)-3'- Fluorophenylethan-1-Ol By Alternaria Alternata Using Ram Horn Peptone In Microbial Growth Medium, Esabi̇ Başaran Kurbanoğlu, Namudar İzzet Kurbanoğlu, Kani̇ Zi̇lbeyaz
Production Of (S)-2'-Fluorophenylethan-1-Ol And (S)-3'- Fluorophenylethan-1-Ol By Alternaria Alternata Using Ram Horn Peptone In Microbial Growth Medium, Esabi̇ Başaran Kurbanoğlu, Namudar İzzet Kurbanoğlu, Kani̇ Zi̇lbeyaz
Turkish Journal of Biology
Enantiomerically pure, fluorinated compounds have an important role in medicinal chemistry. Alternaria alternata isolates were used for the synthesis of (S)-2^'-fluorophenylethan-1-ol 1b and (S)-3^'-fluorophenylethan-1-ol 2b. Biocatalytic syntheses of optically active 1b and 2b were achieved by asymmetric reduction of 2^'-fluoroacetophenone 1a and 3^'-fluoroacetophenone 2a in the batch culture of A. alternata containing ram horn peptone (RHP). The reaction conditions (pH, temperature, and agitation) that improve the conversion of the substrates were studied. The optimal reaction conditions were found as pH 6.0, agitation 250, temperature 32 °C and substrate 3 mmol/100 mL. The gram scale productions of 1b and 2b by …
Effects Of Chromium Vi Stress On Green Alga Ulva Lactuca (L.), Di̇lek Ünal, Nuray O. Işik, Atakan Sukatar
Effects Of Chromium Vi Stress On Green Alga Ulva Lactuca (L.), Di̇lek Ünal, Nuray O. Işik, Atakan Sukatar
Turkish Journal of Biology
In order to contribute to the understanding of its response to metal stress, Ulva lactuca (L.) was treated with different concentration of chromium (VI) (0.2, 0.5, 1, and 5 mM K2CrO4), and alterations in Fv/Fm ratio (maximal photochemical efficiency of PSII) and cell viability were investigated. Significant alterations of the maximal photochemical efficiency of PSII (Fv/Fm) ratio were observed in response to the increase in chromium concentration. The Fv/Fm ratio decreased in Ulva lactuca following 2 h treatment with 1 and 5 mM Cr(VI) solution. The cell viability was decreased in cells exposed to higher Cr(VI) concentrations. Thallus cell morphology …
A Study On The Morphology Of Argulus Foliaceus Lin., 1758 (Crustacea; Branchiura) Procured From Çavuşcu Lake (Central Anatolia-Turkey) With Scanning Electron Microscopy, Ali̇ Alaş, Ahmet Öktener, Kemal Solak
A Study On The Morphology Of Argulus Foliaceus Lin., 1758 (Crustacea; Branchiura) Procured From Çavuşcu Lake (Central Anatolia-Turkey) With Scanning Electron Microscopy, Ali̇ Alaş, Ahmet Öktener, Kemal Solak
Turkish Journal of Biology
In this study, 24 carps (Cyprinus carpio Lin.,1758) caught from Çavuşçu Lake (Konya; 36°41´N, 34°26´E) were examined for metazoan parasites. Infestation rate of Argulus foliaceus Lin.,1758 was found to be 45.8%. In addition, Argulus foliaceus was photographed using a scanning electron microscope (SEM) and a light microscope.
The Effects Of Excessive Mineral Salts And Vitamins On Fiber Cell Thickness In Flax (Linum Usitatissimum L. Cultivar Sarı 85), Hati̇ce Demi̇ray, Ayli̇n Eşi̇z Dereboylu
The Effects Of Excessive Mineral Salts And Vitamins On Fiber Cell Thickness In Flax (Linum Usitatissimum L. Cultivar Sarı 85), Hati̇ce Demi̇ray, Ayli̇n Eşi̇z Dereboylu
Turkish Journal of Biology
The effects of mineral salts on fiber cell thickness in flax (Linum usitatissimum L. cultivar Sarı 85) were investigated in plants grown in medium both rich and poor in mineral salts and vitamins. Three media were investigated: control (MS medium), mineral salt and vitamin deficient MS medium, and mineral salt and vitamin rich MS medium. While chlorophyll a, chlorophyll b, total chlorophyll, and carotenoid pigment content significantly increased in the medium rich in mineral salts and vitamins, they decreased in the medium poor in mineral salts and vitamins. Moreover, the chlorophyll a:chlorophyll b ratio increased in the medium poor in …
Monitoring And Disinfection Of Biofilm-Associated Sulfate Reducing Bacteria On Different Substrata In A Simulated Recirculating Cooling Tower System, Esra İlhan Sungur, İrfan Türetgen, Reza Javaherdashti, Ayşin Çotuk
Monitoring And Disinfection Of Biofilm-Associated Sulfate Reducing Bacteria On Different Substrata In A Simulated Recirculating Cooling Tower System, Esra İlhan Sungur, İrfan Türetgen, Reza Javaherdashti, Ayşin Çotuk
Turkish Journal of Biology
Microbial biofilm and corrosion in cooling systems are the most common problems that damage expensive equipment, cause loss of production, and increase maintenance costs. Sulfate reducing bacteria were considered the major bacterial group involved in microbiologically influenced corrosion (MIC). We investigated the survival and enumeration of biofilm-associated SRB on coupons of galvanized steel, stainless steel, and copper, which are materials used in the manufacturing of cooling systems. We also investigated the effect of monochloromine on SRB as in mixed-species mature biofilms formed on coupons by simulating recirculating cooling water conditions, due to the better penetration feature in biofilms than the …
Phenolic Compounds And Antioxidant And Antimicrobial Properties Of Helichrysum Species Collected From Eastern Anatolia, Turkey, Sevi̇l Albayrak, Ahmet Aksoy, Osman Sağdiç, Ümi̇t Budak
Phenolic Compounds And Antioxidant And Antimicrobial Properties Of Helichrysum Species Collected From Eastern Anatolia, Turkey, Sevi̇l Albayrak, Ahmet Aksoy, Osman Sağdiç, Ümi̇t Budak
Turkish Journal of Biology
The antioxidant activity of the methanolic extracts of 4 plants from genus Helichrysum Mill. (Asteraceae) [H. arenarium (L.) Moench subsp. erzincanicum Davis & Kupicha, H. arenarium (L.) Moench subsp. rubicundum (C.Koch.) Davis & Kupicha, H. armenium DC. subsp. araxinum (Kirp.) Takht., and H. plicatum DC. subsp. pseudoplicatum (Nab.) Davis & Kupicha] was investigated with 2 complementary test systems, DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging and phosphomolybdenum assay. H. plicatum subsp. pseudoplicatum showed the highest level of total antioxidant activity (161.79 ± 0.3 mg ascorbic acid equivalent/g extract) in the phosphomolybdenum assay. H. arenarium subsp. erzincanicum showed the highest level of free radical …
Response Of Photosynthesis In The Leaves Of Cucumber Seedlings To Light Intensity And Co2 Concentration Under Nitrate Stress, Xiaoyu Yang, Xiufeng Wang, Min Wei
Response Of Photosynthesis In The Leaves Of Cucumber Seedlings To Light Intensity And Co2 Concentration Under Nitrate Stress, Xiaoyu Yang, Xiufeng Wang, Min Wei
Turkish Journal of Botany
The effects of 2 nitrate levels, 14 (CK) and 140 mmol L^{-1} (T), on the leaf gas exchange variables of cucumber (Cucumis sativus L. cv. Xintaimici) seedlings grown in hydroponic culture were investigated. Photosynthetic light- and CO_{2}-response curves from CK and T seedlings were determined and used for the analysis of photosynthetic capacity. The results showed that nitrate stress resulted in a significant reduction of net photosynthesis of T seedlings compared with CK. At the same time, the apparent quantum yield, light-saturated net photosynthesis, carboxylation efficiency, and CO_{2}-saturated net photosynthesis in nitrate-stressed cucumbers also decreased significantly with the increase of …
Differential Power Analysis Resistant Hardware Implementation Of The Rsa Cryptosystem, Kekli̇k Alpteki̇n Bayam, Berna Örs
Differential Power Analysis Resistant Hardware Implementation Of The Rsa Cryptosystem, Kekli̇k Alpteki̇n Bayam, Berna Örs
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, RSA cryptosystem was implemented on hardware, then modified to be resistant against Differential Power Analysis attacks by using the Randomized Table Window method. This is the first FPGA realization of an algorithmic countermeasure which makes RSA resistant to power analysis attacks. Modular exponentiation is realized with Montgomery Modular Multiplication. The Montgomery modular multiplier has been realized with Carry-Save Adders. Carry-Save representation has been used throughout the RSA encryption algorithm. The primarily implemented RSA architecture prevents the extraction of the secret key using Simple Power Analysis attacks. When comparing the protected implementation with the unprotected, it can be …
Cover And Contents
Turkish Journal of Electrical Engineering and Computer Sciences
No abstract provided.
Experimental Studies Of A Scaled-Down Tsr-Based Svc And Tcr-Based Svc Prototype For Voltage Regulation And Compensation, Ayetül Gelen, Tankut Yalçinöz
Experimental Studies Of A Scaled-Down Tsr-Based Svc And Tcr-Based Svc Prototype For Voltage Regulation And Compensation, Ayetül Gelen, Tankut Yalçinöz
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, prototypes of two shunt flexible AC transmission system (FACTS) devices, a thyristor switched reactor (TSR)-based static VAr compensator (SVC) and a thyristor controlled reactor (TCR)-based static VAr compensator- have been developed. The design and testing of both a TSR-based SVC and a TCR-based SVC are accomplished in the Power Systems Research Laboratory of Nigde University. The TSR-based SVC and TCR-based SVC devices are studied in three-bus and single machine infinite bus systems for three-phase static load conditions. The effects of TSR-based SVC and TCR-based SVC devices on load voltages are also analyzed. Experimental results show that significant …
An Rfid Based Indoor Tracking Method For Navigating Visually Impaired People, Ruşen Öktem, Eli̇f Aydin
An Rfid Based Indoor Tracking Method For Navigating Visually Impaired People, Ruşen Öktem, Eli̇f Aydin
Turkish Journal of Electrical Engineering and Computer Sciences
This paper tackles the RFID based tracking problem in an obscured indoor environment. The proposed solution is an integral part of a navigation aid for guiding visually impaired people in a store. It uses RF signal strengths and is based on the Bayes Decision Theory. An observation vector is formed by received radio signal strength indication values, transmitted from three transmitters at distinct frequencies in the UHF band. The indoor area is divided into square grids, where each grid is considered as a class. The problem of tracking is expressed as classifying the observed radio signal strengths to the most …
Oceanography Radar System Wera: Features, Accuracy, Reliability And Limitations, Thomas Helzel, Matthias Kniephoff, Leif Petersen
Oceanography Radar System Wera: Features, Accuracy, Reliability And Limitations, Thomas Helzel, Matthias Kniephoff, Leif Petersen
Turkish Journal of Electrical Engineering and Computer Sciences
The WERA system (WavE RAdar) is a shore based remote sensing system to monitor ocean surface currents, waves and wind direction. This long range, high resolution monitoring system based on short radio wave radar technology. The vertical polarised electromagnetic wave is coupled to the conductive ocean surface and follows the curvature of the earth. This over the horizon oceanography radar can pick up back-scattered signals from the rough ocean surface (Bragg effect) from ranges of up to 200 km. The physical background, technical concept and environmental boundary conditions are explained. Results for various installations from all over the world demonstrates …
Modeling And Simulation Strategies In High Frequency Surface Wave Radars, Levent Sevgi̇
Modeling And Simulation Strategies In High Frequency Surface Wave Radars, Levent Sevgi̇
Turkish Journal of Electrical Engineering and Computer Sciences
Surface Wave High Frequency Radars (SWHFR) are taken into account in the content of modeling and simulation challenges. Examples related to multi-mixed path surface wave propagation, radar cross section (RCS) prediction, and total radar echo showing target, clutter, noise, and interference are presented.
Implementation Of Method For Operating Multiple High Frequency Surface Wave Radars On A Common Carrier Frequency, Ryan Riddolls
Implementation Of Method For Operating Multiple High Frequency Surface Wave Radars On A Common Carrier Frequency, Ryan Riddolls
Turkish Journal of Electrical Engineering and Computer Sciences
The increasing use of High Frequency Surface Wave Radar (HFSWR) for the surveillance of coastal regions is faced with the problem of limited channel availability in the electromagnetic spectrum. Thus, there is a need for multiple radars to share a common frequency channel. Proof-of-concept work is presented here for a method to operate multiple radar systems on a common carrier frequency. A review is provided of an existing concept where a common waveform is modulated by tones varying by a few hertz across the different radars. The signals from the different radars are separated by either pulse-domain filtering or Doppler …
Securing Fuzzy Vault Schemes Through Biometric Hashing, Cengi̇z Örenci̇k, Thomas Brochmann Pedersen, Erkay Savaş, Mehmet Keski̇nöz
Securing Fuzzy Vault Schemes Through Biometric Hashing, Cengi̇z Örenci̇k, Thomas Brochmann Pedersen, Erkay Savaş, Mehmet Keski̇nöz
Turkish Journal of Electrical Engineering and Computer Sciences
The fuzzy vault scheme is a well-known technique to mitigate privacy, security, and usability related problems in biometric identification applications. The basic idea is to hide biometric data along with secret information amongst randomly selected chaff points during the enrollment process. Only the owner of the biometric data who presents correct biometrics can recover the secret and identify himself. Recent research, however, has shown that the scheme is vulnerable to certain types of attacks. The recently proposed ``correlation attack'', that allows linking two vaults of the same biometric, pose serious privacy risks that have not been sufficiently addressed. The primary …
Corrective Action Planning Considering Facts Allocation And Optimal Load Shedding Using Bacterial Foraging Oriented By Particle Swarm Optimization Algorithm, Rahmat Allah Hooshmand, Mostafa Ezatabadi
Corrective Action Planning Considering Facts Allocation And Optimal Load Shedding Using Bacterial Foraging Oriented By Particle Swarm Optimization Algorithm, Rahmat Allah Hooshmand, Mostafa Ezatabadi
Turkish Journal of Electrical Engineering and Computer Sciences
Reactive power planning (RPP) involves optimal allocation and determination of the type and size of new reactive power (VAR) supplies to satisfy voltage constraints during normal and contingency states. The RPP issue is in fact an optimization of large scale mixed integer nonlinear programming problem, so it is proper to use an evolutionary algorithm to solve the problem. In this paper, in order to solve the RPP problem for corrective action of power systems, the bacterial foraging (BF) oriented by particle swarm optimization (PSO) algorithm (BF-PSO) is proposed. In the algorithm, the VAR control has been carried out by using …
Adaptive Neuro-Fuzzy Inference System To Improve The Power Quality Of Variable-Speed Wind Power Generation System, Yüksel Oğuz, Kami̇l Ri̇fat İrfan Güney
Adaptive Neuro-Fuzzy Inference System To Improve The Power Quality Of Variable-Speed Wind Power Generation System, Yüksel Oğuz, Kami̇l Ri̇fat İrfan Güney
Turkish Journal of Electrical Engineering and Computer Sciences
In this study, an adaptive neuro-fuzzy inference system is designed for output voltage and frequency control of a variable-speed wind power generation system. Variable-speed wind power generation systems (VSWPGS) provide the opportunity to capture more power than fixed speed turbines. On the other hand, the variable-speed wind turbine output can be variable voltage and variable frequency for fluctuating wind speeds. The quality of output power can be improved if adequate controls are incorporated in the system. To bring the output voltage and frequency of system by means of control of blade pitch angle of wind turbine to a desirable value, …
The Analysis Of A Semiconductor Single Asymmetric And Symmetric Step-Index Laser For Even And Odd Fields By Alpha Method, Mustafa Temi̇z, Mehmet Ünal
The Analysis Of A Semiconductor Single Asymmetric And Symmetric Step-Index Laser For Even And Odd Fields By Alpha Method, Mustafa Temi̇z, Mehmet Ünal
Turkish Journal of Electrical Engineering and Computer Sciences
In this work, semiconductor step-index single waveguide has been analyzed by Alpha Method. A requested quantity of wave guide can be obtained in terms of normalized propagation constant, which is represented by alpha belonging to active region. Based on this method, structural properties of the material containing any requested quantity of the waveguide is theoretically calculated, when the width of the active region, the refractive indices of the regions and the wavelength are given. In the TE mode some important parameters, such as the propagation constants for regions of the semiconductor step-index single waveguide, the wave numbers, the effective index …
Fractional Order Sliding Mode Control With Reaching Law Approach, Mehmet Önder Efe
Fractional Order Sliding Mode Control With Reaching Law Approach, Mehmet Önder Efe
Turkish Journal of Electrical Engineering and Computer Sciences
Fractional order sliding mode control is studied in this paper. The control objectives are achieved by adopting the reaching law approach of sliding mode control. The main contribution of this work is to show that the philosophy of integer order sliding mode control is valid also for the systems represented by fractional order operators. A sufficient condition and its implications for stability are given. Matched and unmatched uncertainties are studied. The attractor nature of the switching manifold is analyzed together with a stable sliding subspace design condition. The claims are justified through a set of simulations and the results obtained …
A Novel Algorithm For Sensorless Motion Control Of Flexible Structures, Islam Shoukry Mohammed Khalil, Emrah Deni̇z Kunt, Asif Sabanovic
A Novel Algorithm For Sensorless Motion Control Of Flexible Structures, Islam Shoukry Mohammed Khalil, Emrah Deni̇z Kunt, Asif Sabanovic
Turkish Journal of Electrical Engineering and Computer Sciences
This article demonstrates the validity of using an actuator as a single platform for measurements during a motion control assignment of flexible systems kept free from any kind of measurement. System acceleration level dynamics, parameters and interaction forces with the environment are coupled in an incident reaction torque that naturally rises when a flexible system is subjected to an action imposed by an attached actuator to the system. This work attempts to decouple each of the system parameters out of the incident coupled reaction torque at the interface point of the actuator with the flexible system by way of measurements …
Modeling And Control Of Flow Problems By Adaptation-Based Linear Parameter Varying Models, Coşku Kasnakoğlu
Modeling And Control Of Flow Problems By Adaptation-Based Linear Parameter Varying Models, Coşku Kasnakoğlu
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper a systematic modeling and control approach for flow problems is considered. A nonlinear Galerkin model is obtained from the partial differential equations (PDEs) describing the flow; and a Linear Parameter Varying (LPV) model is constructed to approximate the Galerkin model, where the parameter variation of the LPV model is controller by an adaptation mechanism. The LPV model is then treated as a surrogate on which the control design is carried out, where the parameter variations provide a range of uncertainty in which the control design must perform satisfactorily. It is shown that if certain conditions are met, …