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2014

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A Behavioral Analysis Of Achromatic Cue Perception By The Ant Cataglyphis Aenescens (Hymenoptera; Formicidae), Volkan Aksoy, Yilmaz Çamlitepe Jan 2014

A Behavioral Analysis Of Achromatic Cue Perception By The Ant Cataglyphis Aenescens (Hymenoptera; Formicidae), Volkan Aksoy, Yilmaz Çamlitepe

Turkish Journal of Zoology

Behavioral responses of Cataglyphis aenescens foragers to various monochromatic light stimuli were tested. Foragers were trained to associate lights of 370 (UV), 440 (blue), 540 (green), and 640 nm (red) with a food reward on a circular orientation platform and were then tested to determine the threshold intensity values of these wavelengths they could perceive. Foragers significantly responded to all wavelengths at training intensities but their homeward orientation diminished with decreasing stimulus intensity. The results showed that UV and green lights could be perceived at lower intensities compared to blue and red lights. Foragers were further trained in a Y-maze …


Age-Dependent Variations In The Venom Proteins Of Vipera Kaznakovi Nikolsky, 1909 And Vipera Ammodytes (Linnaeus, 1758) (Ophidia: Viperidae), Hüseyi̇n Arikan, Bayram Göçmen, Naşi̇t İğci̇, Bahadir Akman Jan 2014

Age-Dependent Variations In The Venom Proteins Of Vipera Kaznakovi Nikolsky, 1909 And Vipera Ammodytes (Linnaeus, 1758) (Ophidia: Viperidae), Hüseyi̇n Arikan, Bayram Göçmen, Naşi̇t İğci̇, Bahadir Akman

Turkish Journal of Zoology

Polyacrylamide disc gel electrophoresis and densitometry analysis were used to analyze venom extracts of Vipera kaznakovi (16.5, 30, and 55 cm) and Vipera ammodytes (28.5, 36.7, and 51.5 cm) specimens of 3 different lengths. V. kaznakovi specimens were collected from Hopa (Artvin Province); 2 V. ammodytes specimens were from Ağva (İstanbul Province) and the longest one was from Yuvacık (Kocaeli Province). The electropherograms of the venom protein samples showed age-dependent qualitative and quantitative variations.


Herpetofauna Of The Vicinity Of Akşehir And Eber (Konya, Afyon), Turkey, Durmuş Ci̇han, Cemal Varol Tok Jan 2014

Herpetofauna Of The Vicinity Of Akşehir And Eber (Konya, Afyon), Turkey, Durmuş Ci̇han, Cemal Varol Tok

Turkish Journal of Zoology

In this research, 29 species of 11 amphibian and reptile families were detected in the endorheic basin of Akşehir and Eber. Of these species, 5 are anurans, 1 is a tortoise, 1 is a turtle, 9 are lizards, and 13 are snakes. In addition, the chorotype classification of the species recorded in the study area and their distributions depending on plants are also provided. It was established that specimens of subspecies Ophisops elegans macrodactylus and O. e. centralanatolia were sympatrically found in the vicinity of Ortaköy and Tuzlukçu. Moreover, in addition to the species determined in previous studies, Platyceps najadum …


Selective Predation On Common Voles By Tawny Owls And Long-Eared Owls In Winter And Spring, Linas Balciauskas, Laima Balciauskiene Jan 2014

Selective Predation On Common Voles By Tawny Owls And Long-Eared Owls In Winter And Spring, Linas Balciauskas, Laima Balciauskiene

Turkish Journal of Zoology

We studied size preferences of Tawny (Strix aluco) and Long-eared (Asio otus) Owls preying on common voles (Microtus arvalis) in the winter and spring seasons in Central Lithuania. Regression equations were used for body mass estimations. We found that both A. otus and S. aluco preferred larger M. arvalis than the average available in the population (the average body mass of predated individuals was 21.45 ± 0.12 g compared to 16.42 ± 0.16 g of snap-trapped individuals). Irrespective of the owl species, most of the predated Microtus voles were adults. In S. aluco prey, the winter proportion of young voles …


Local Concentration Of Foraging Noctule Bats (Nyctalus Noctula) As A Possible Tool To Assess The Density Of Bats In Large Forest Complexes, Michal Polakowski, Monika Broniszewska, Ireneusz Ruczynski Jan 2014

Local Concentration Of Foraging Noctule Bats (Nyctalus Noctula) As A Possible Tool To Assess The Density Of Bats In Large Forest Complexes, Michal Polakowski, Monika Broniszewska, Ireneusz Ruczynski

Turkish Journal of Zoology

Concentrations of at least 600 hunting noctule bats Nyctalus noctula were observed over the artificial shallow reservoir Siemianówka in eastern Poland. The observation indicates that noctule bats concentrate hunting during the presence of vast amounts of insects over the reservoir. We suggest that the high concentrations of noctule bats provide a potential tool for the estimation of local population size or density in large forest complexes.


Breeding Success Of The Stone Curlew Burhinus Oedicnemus In Nag Valley (1999-2001), Kharan, Pakistan, Muhammad Sajid Nadeem, Tariq Mahmood, Muhammad Mahmood-Ul-Hassan Jan 2014

Breeding Success Of The Stone Curlew Burhinus Oedicnemus In Nag Valley (1999-2001), Kharan, Pakistan, Muhammad Sajid Nadeem, Tariq Mahmood, Muhammad Mahmood-Ul-Hassan

Turkish Journal of Zoology

Variations in different breeding parameters in 2 adjacent populations of the Stone Curlew in Nag Valley were studied. A total of 106 active nests were spotted, with an overall mean clutch size of 1.42 eggs per nest. The nest and egg success of the Lope Valley population was 0.50 and 0.42, respectively, while the nest and egg success of the Kereichi population was 0.60 and 0.45. Poaching of eggs/chicks, habitat shrinkage, overgrazing, and fuel wood collection are thoughts to be the main factors affecting the breeding success of Stone Curlew in the area.


Phoretic Mites In Uni- And Bivoltine Populations Of Ips Typographus: A 1-Year Case Study, Martin Cejka, Jaroslav Holusa Jan 2014

Phoretic Mites In Uni- And Bivoltine Populations Of Ips Typographus: A 1-Year Case Study, Martin Cejka, Jaroslav Holusa

Turkish Journal of Zoology

Members of the order Mesostigmata frequently use other animals to colonize suitable habitats, and thus their phoretic exploitation of bark beetles is not exceptional. We compared the abundance and species spectrum of phoretic mites in univoltine and bivoltine populations of the European spruce bark beetle Ips typographus. Two localities with high population densities of Ips typographus in the eastern part of the Czech Republic (400 and 1100 m a.s.l.) were studied. Beetles were sampled with pheromone traps baited with IT Ecolure (5 per locality). In total, 1268 I. typographus individuals were captured, from which 1662 mite individuals were collected and …


An Institutional Alchemy: India’S Two Parliaments In Comparative Perspective, Shubhankar Dam Jan 2014

An Institutional Alchemy: India’S Two Parliaments In Comparative Perspective, Shubhankar Dam

Research Collection Yong Pung How School Of Law

India has a parliamentary system. But articled in India’s Constitution is a provision that authorizes the President to occasionally enact legislation without involving Parliament. Such presidential legislation are called ordinances, not Acts; and rather than enact, the President promulgates them. Textually, ordinances are bounded by several ‘controls’. They are limited to circumstances when at least one House of Parliament is not in session, and the President is satisfied that the circumstances are such that immediate action is necessary. And without such formal parliamentary approval after a specified duration, they cease to exist. But after sixty years of constitutional practice these …


Measuring The Transplantation Of English Commercial Law In A Small Jurisdiction: An Empirical Study Of Singapore’S Insurance Judgments Between 1965 And 2012, Christopher Chen Jan 2014

Measuring The Transplantation Of English Commercial Law In A Small Jurisdiction: An Empirical Study Of Singapore’S Insurance Judgments Between 1965 And 2012, Christopher Chen

Research Collection Yong Pung How School Of Law

This article seeks to measure the development of law after transplanting common law and statutes from another country by conducting an empirical study of the citation of precedents and demography of disputes of insurance cases in Singapore. This article recognizes that there are justifications for Singapore to transplant English insurance law. However, this research shows that the transplantation of English commercial law into a small jurisdiction, even within the common law family, may cause the law to be in a static state if courts do not have enough cases to maintain the development of law or to consider new development …


Redefining Relevancy And Exclusionary Discretion In Sir James Fitzjames Stephen’S Indian Evidence Act Of 1872: The Singapore Experiment And Lessons For Other Indian Evidence Act Jurisdictions, Siyuan Chen Jan 2014

Redefining Relevancy And Exclusionary Discretion In Sir James Fitzjames Stephen’S Indian Evidence Act Of 1872: The Singapore Experiment And Lessons For Other Indian Evidence Act Jurisdictions, Siyuan Chen

Research Collection Yong Pung How School Of Law

In many jurisdictions, the rules of evidence can often be instrumental in determining the outcome of a dispute. But to what extent can evidence law be controlled by codification, or is it better to leave its regulation and development to the judges via common law? In an attempt to bridge the gap between the rules of an antiquated evidence statute and the modern realities of practice, Singapore’s Evidence Act was amended in 2012. Certain relevancy provisions were amended to allow greater admissibility of evidence, while new provisions were introduced to act as a check against abuse. However, it will be …


Sovereignty, Territoriality, And The Enforcement Of Foreign Judgments, George Rutherglen, James Y. Stern Jan 2014

Sovereignty, Territoriality, And The Enforcement Of Foreign Judgments, George Rutherglen, James Y. Stern

Faculty Publications

No abstract provided.


Supporting And Promoting Scholarly Life In Turbulent Times, A. Benjamin Spencer Jan 2014

Supporting And Promoting Scholarly Life In Turbulent Times, A. Benjamin Spencer

Faculty Publications

One of the most important contributions a law school can make is to the development of the law through scholarly research. As one of the three pillars of being an academic-the other two being teaching and service-producing legal scholarship in one's respective area of expertise is an enterprise that nearly all law schools would like to support. However, during these challenging times for legal education arising from enrollment declines and the resultant adverse budgetary impacts, fully supporting legal scholarship can be particularly challenging. Having served as Associate Dean for Research I at Washington & Lee University School of Law ("W …


The Impact Of Eu Law On A National Competition Authority's Leniency Programme – The Case Of Poland, Piotr Sitarek Jan 2014

The Impact Of Eu Law On A National Competition Authority's Leniency Programme – The Case Of Poland, Piotr Sitarek

Yearbook of Antitrust and Regulatory Studies

This paper is devoted to the impact of EU law on national leniency programmes, especially the Polish one. It analyses the jurisprudence of the Court of Justice in Pfleiderer, Donau Chemie and Schenker and identifies three specific areas of potential EU influence on national leniency programmes. The impact of EU law on the rules of access to leniency documents is analysed in detail on the basis of both EU and Polish law and taking into account the Draft Directive on Antitrust Damages Actions. The paper covers also the extent to which the principle of effectiveness of EU law limits the …


A Performance Comparison Of Linear And Nonlinear Control Of A Scig-Wind Farm Connecting To A Distribution Network, Mohamed Benchagra, Mohamed Maaroufi, Mohammed Ouassaid Jan 2014

A Performance Comparison Of Linear And Nonlinear Control Of A Scig-Wind Farm Connecting To A Distribution Network, Mohamed Benchagra, Mohamed Maaroufi, Mohammed Ouassaid

Turkish Journal of Electrical Engineering and Computer Sciences

This study presents a comparison of linear and nonlinear control to regulate the DC-link voltage and power factor correction of a wind farm equipped with squirrel cage induction generators (SCIGs), connecting to a 22-kV distribution network. Both active and reactive powers are employed in 2 independent control laws. The proposed control strategies are derived from the Lyapunov approach. The aim of the control is to maximize the generated power with the lowest possible impact in the grid voltage and frequency during normal operation and under the occurrence of faults. The nonlinear backstepping controller to be used for the control of …


Coherence Analysis On Thermal Effect For Power Cables Under Different Environmental Conditions, Sezai̇ Taşkin, Şahi̇n Serhat Şeker, Özcan Kalenderli̇, Murat Karahan Jan 2014

Coherence Analysis On Thermal Effect For Power Cables Under Different Environmental Conditions, Sezai̇ Taşkin, Şahi̇n Serhat Şeker, Özcan Kalenderli̇, Murat Karahan

Turkish Journal of Electrical Engineering and Computer Sciences

There are 2 important aspects of this research; these are the experimental study and the data analysis, which are based on coherence analysis. In this study, a low-voltage power cable is tested under 2 different environments, air and water, and the variations in temperature are measured for the conductor, the sheath parts of the cable, and the environment. The recorded test data are analyzed using such as coherence analysis. This in turn provides the means to determine the relationship among the sheath, conductor, and the environment. In conclusion, high correlated peaks in the frequency domain are used to determine the …


Inverse Covariance Principal Component Analysis For Power System Stability Studies, Abdullah Alodienat, Tauseef Gulrez Jan 2014

Inverse Covariance Principal Component Analysis For Power System Stability Studies, Abdullah Alodienat, Tauseef Gulrez

Turkish Journal of Electrical Engineering and Computer Sciences

The dominant poles (eigenvalues) of system matrices are used extensively in determining the power system stability analysis. The challenge is to find an accurate and efficient way of computing these dominant poles, especially for large power systems. Here we present a novel way for finding the system stability based on inverse covariance principal component analysis (ICPCA) to compute the eigenvalues of large system matrices. The efficacy of the proposed method is shown by numerical calculations over realistic power system data and we also prove the possibility of using ICPCA to determine the eigenvalues closest to any damping ratio and repeated …


Rfid And Communication Technologies For An Intelligent Bus Monitoring And Management System, Mahammad Abdul Hannan, Aishah Mustapha, Abdulla Al Mamun, Aini Hussain, Hassan Basri Jan 2014

Rfid And Communication Technologies For An Intelligent Bus Monitoring And Management System, Mahammad Abdul Hannan, Aishah Mustapha, Abdulla Al Mamun, Aini Hussain, Hassan Basri

Turkish Journal of Electrical Engineering and Computer Sciences

This paper highlights the implementation of an intelligent bus monitoring system based on current challenges and problems. In this system, radio frequency identification and integrated sensing technologies, such as a global positioning system, general packet radio service, and geographic information system, are used to monitor the movement of a bus. A new theoretical framework and ruled-based decision algorithms are developed for the system. An experimental setup is developed for the prototype implementation. The results show that the choice of integrated technologies used in the system is suitable to monitor and manage a vehicle transportation system.


A Methodology For Memristance Calculation, Reşat Mutlu, Ertuğrul Karakulak Jan 2014

A Methodology For Memristance Calculation, Reşat Mutlu, Ertuğrul Karakulak

Turkish Journal of Electrical Engineering and Computer Sciences

A memristor is a newly found fundamental circuit element whose behavior can be predicted using either the charge-dependent function called memristance or the flux-dependent function called memductance. Therefore, it is important to find the memristance or memductance function of a memristor. To the best of our knowledge, there is no methodology describing how to obtain the memristance function or memristor characteristic in the literature for this purpose as of yet. In this work, a methodology is suggested to find the memristance or memductance functions. The methodology suggests first doing several experiments with a memristor using a square-wave signal to acquire …


Increasing Key Space At Little Extra Cost In Rfid Authentications, Gökhan Dalkiliç, Mehmet Hi̇lal Özcanhan, Hafi̇ze Şen Çakir Jan 2014

Increasing Key Space At Little Extra Cost In Rfid Authentications, Gökhan Dalkiliç, Mehmet Hi̇lal Özcanhan, Hafi̇ze Şen Çakir

Turkish Journal of Electrical Engineering and Computer Sciences

Traditional authentication and key establishment protocols utilize nonce parameters as a means for message freshness, recent aliveness, and key derivation. Improving identity verification, increasing key space, or making secret updates more complex through nonces are not goals. Generating random numbers as nonces and not making the most out of them can be considered as a loss in resource stricken radio frequency identification (RFID) tags. By increasing the shared secrets slightly, a new functionality for the nonces is introduced, which makes the authentication and key establishment protocols of RFID systems more secure, in general. The proposed method contributes to the security …


A Low-Memory Intensive Decoding Architecture For Double-Binary Convolutional Turbo Code, Ming Zhan, Liang Zhou, Jun Wu Jan 2014

A Low-Memory Intensive Decoding Architecture For Double-Binary Convolutional Turbo Code, Ming Zhan, Liang Zhou, Jun Wu

Turkish Journal of Electrical Engineering and Computer Sciences

Memory accesses take a large part of the power consumption in the iterative decoding of double-binary convolutional turbo code (DB-CTC). To deal with this, a low-memory intensive decoding architecture is proposed for DB-CTC in this paper. The new scheme is based on an improved maximum a posteriori probability algorithm, where instead of storing all of the state metrics, only a part of these state metrics is stored in the state metrics cache (SMC), and the memory size of the SMC is thus reduced by 25%. Owing to a compare-select--recalculate processing (CSRP) module in the proposed decoding architecture, the unstored state …


Spatiotemporal Realization Of An Artificial Retina Model And Performance Evaluation Through Isi- And Spike Count-Based Image Reconstruction Methods, İrfan Karagöz, Mustafa Özden Jan 2014

Spatiotemporal Realization Of An Artificial Retina Model And Performance Evaluation Through Isi- And Spike Count-Based Image Reconstruction Methods, İrfan Karagöz, Mustafa Özden

Turkish Journal of Electrical Engineering and Computer Sciences

Development of an artificial retina model that can mimic the biologic retina is a highly challenging task and this task is an important step in the development of a visual prosthesis. The receptive field structure of the retina layer is usually modeled as a 2D difference of Gaussian (DOG) filter profile. In the present study, as a different approach, a retina model including a 3D 2-stage DOG filter (3D-ADOG) that has an adaptively changing bandwidth with respect to the local image statistic is developed. Using this modeling, the adaptive image processing of the retina can be realized. The contribution of …


A Penalty Function Method For Designing Efficient Robust Classifiers With Input Space Optimal Separating Surfaces, Ayşegül Uçar, Yakup Demi̇r, Cüneyt Güzeli̇ş Jan 2014

A Penalty Function Method For Designing Efficient Robust Classifiers With Input Space Optimal Separating Surfaces, Ayşegül Uçar, Yakup Demi̇r, Cüneyt Güzeli̇ş

Turkish Journal of Electrical Engineering and Computer Sciences

This paper considers robust classification as a constrained optimization problem. Where the constraints are nonlinear, inequalities defining separating surfaces, whose half spaces include or exclude the data depending on their classes and the cost, are used for attaining robustness and providing the minimum volume regions specified by the half spaces of the surfaces. The constraints are added to the cost using penalty functions to get an unconstrained problem for which the gradient descent method can be used. The separating surfaces, which are aimed to be found in this way, are optimal in the input data space in contrast to the …


Applications Of Wavelets And Neural Networks For Classification Of Power System Dynamics Events, Samir Avdakovic, Amir Nuhanovic, Mirza Kusljugic, Elvisa Becirovic Jan 2014

Applications Of Wavelets And Neural Networks For Classification Of Power System Dynamics Events, Samir Avdakovic, Amir Nuhanovic, Mirza Kusljugic, Elvisa Becirovic

Turkish Journal of Electrical Engineering and Computer Sciences

This paper investigates the possibility of classifying power system dynamics events using discrete wavelet transform (DWT) and a neural network (NN) by analyzing one variable at a single network bus. Following a disturbance in the power system, it will propagate through the system in the form of low-frequency electromechanical oscillations (LFEOs) in a frequency range of up to 5 Hz. DWT allows the identification of components of the LFEO, their frequencies, and magnitudes. After determining the energy components' share of the analyzed signal using DWT and Parseval's theorem, the input data for the classification process using a NN are obtained. …


Design, Optimization, And Realization Of A Wire Antenna With A 25:1 Bandwidth Ratio For Terrestrial Communications, Korkut Yeği̇n Jan 2014

Design, Optimization, And Realization Of A Wire Antenna With A 25:1 Bandwidth Ratio For Terrestrial Communications, Korkut Yeği̇n

Turkish Journal of Electrical Engineering and Computer Sciences

Wire antennas can be made wideband if the antenna is loaded with passive elements and connected to a lossless matching network. However, realization of the load component values and matching network can easily become impractical. In this study, using only a surface mount and standard component values, antenna loads and a matching network are optimized using genetic algorithms. The optimized design achieves a 25:1 bandwidth ratio, from 20 MHz to 500 MHz, with a maximum voltage standing wave ratio (VSWR) of 3.5 and minimum system gain of --5 dBi. The antenna system gain at azimuth is taken as the objective …


A New Method For Extraction Of Speech Features Using Spectral Delta Characteristics And Invariant Integration, Hassan Farsi, Samana Kuhimoghadam Jan 2014

A New Method For Extraction Of Speech Features Using Spectral Delta Characteristics And Invariant Integration, Hassan Farsi, Samana Kuhimoghadam

Turkish Journal of Electrical Engineering and Computer Sciences

We propose a new feature extraction algorithm that is robust against noise. Nonlinear filtering and temporal masking are used for the proposed algorithm. Since the current automatic speech recognition systems use invariant-integration and delta-delta techniques for speech feature extraction, the proposed algorithm improves speech recognition accuracy appropriately using a delta-spectral feature instead of invariant integration. One of the nonenvironmental factors that reduce recognition accuracy is the vocal tract length (VTL), leading to a mismatch between the training and testing data. We can use the invariant-integration feature idea for decreasing the VTL effects. The aim of this paper is to provide …


Continuity Of Currents Across Neighboring Cells In Pmm Analysis Of Thin-Wire Grids, Sena Esen Bayer Keski̇n, Ahmet Ari̇f Ergi̇n Jan 2014

Continuity Of Currents Across Neighboring Cells In Pmm Analysis Of Thin-Wire Grids, Sena Esen Bayer Keski̇n, Ahmet Ari̇f Ergi̇n

Turkish Journal of Electrical Engineering and Computer Sciences

This article presents a new approach for the analysis of electromagnetic scattering from a rectangular wire mesh. In this sense, a basis function that considers the flow of a current from one cell to the next is proposed in light of Floquet's theorem. The proposed basis function enables the use of periodic method of moments in frequency-selective surfaces composed of thin wires in the case of a system having a connection with neighboring cells, such as thin-wire grids. The validity of the proposed solution approach is tested in 2 distinct cases (with and without a neighbor connection) for scattered fields. …


Neuro-Fuzzy Network Approach For Modeling Submicron Mosfets: Application To Mosfet Subcircuit Simulation, Amirhossein Abdollahinohoji, Fardad Farokhi, Majid Zamani Jan 2014

Neuro-Fuzzy Network Approach For Modeling Submicron Mosfets: Application To Mosfet Subcircuit Simulation, Amirhossein Abdollahinohoji, Fardad Farokhi, Majid Zamani

Turkish Journal of Electrical Engineering and Computer Sciences

A neuro-fuzzy network approach is developed to model the nonlinear behavior of submicron metal-oxide semiconductor field-effect transistors (MOSFETs). The proposed model is trained and implemented as a MOSFET in a software environment. The training data are obtained through various simulations of a MOSFET Berkeley short channel insulated-gate field-effect transistor model 3 (BSIM3) in HSPICE, and the trained model is utilized to simulate the MOSFET device. The obtained result shows good and noticeable agreement between the numerical result of the original model in HSPICE and the neuro-fuzzy approach in the device and subcircuit modeling.


Simultaneous Identification And Correction Of Measurement And Branch Parameter Errors, Mehdi Ahmadi Jirdehi, Mehrdad Tarafdar Hagh, Kazem Zare Jan 2014

Simultaneous Identification And Correction Of Measurement And Branch Parameter Errors, Mehdi Ahmadi Jirdehi, Mehrdad Tarafdar Hagh, Kazem Zare

Turkish Journal of Electrical Engineering and Computer Sciences

The performance of the state estimation (SE) depends on the accuracy of the received measured data, as well as the parameter data of the power system. In this paper, a new algorithm is proposed for the simultaneous identification and correction of measurement and branch parameter errors (series and shunt admittances) in the power system SE problem. The proposed method uses Lagrange multipliers for the identification and correction of branch parameter errors without the need for a-priori specification of suspect parameter vectors. Erroneous measurements and branch parameter values can be corrected using the proposed method to estimate the measurement and branch …


Fuzzy Impedance And Force Control Of A Stewart Platform, Selçuk Ki̇zi̇r, Zafer Bi̇ngül Jan 2014

Fuzzy Impedance And Force Control Of A Stewart Platform, Selçuk Ki̇zi̇r, Zafer Bi̇ngül

Turkish Journal of Electrical Engineering and Computer Sciences

A new, simple, and effective control method is proposed for the position-based impedance and force control of a Stewart platform (SP). The control approach can be divided into 3 parts, namely position control in free space, impedance control in contact, and force control. An impedance filter is developed to achieve the desired behavior between the position and force. The gain of the filter is modified by a fuzzy logic proportional-integral-derivative controller. Kinematic and dynamic models of the SP are simulated in a MATLAB/Simulink environment. Several real-time experiments are conducted with the SP developed in our laboratory. The results of the …


Fuzzy Logic Approach To Henry Factor For Distributed Feedback Laser Case, Abdullah Çavuşoğlu Jan 2014

Fuzzy Logic Approach To Henry Factor For Distributed Feedback Laser Case, Abdullah Çavuşoğlu

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, a simple approach for intelligent modeling of the Henry factor (\alpha-alpha parameter, antiguiding factor, phase-amplitude coupling factor) or the so-called linewidth enhancement factor, which is an actual analysis and design parameter for semiconductor laser diodes and optical communication systems, is proposed based on the fuzzy logic (FL) phenomenon. The proposed FL-based model easily computes the Henry factor in terms of different wavelengths and injection current levels (i.e. the inputs of the model). The experimental data belong to a distributed feedback laser, obtained from amplified spontaneous emission spectra, which is among the techniques required for the characterization of …