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2019

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Computational Gene Association Based On Relative Species Displacement In Gene And Morphology Trees, Martin D. Hellwig Jan 2019

Computational Gene Association Based On Relative Species Displacement In Gene And Morphology Trees, Martin D. Hellwig

Open Access Dissertations

While a number of methods exist for gene based fin prediction, these studies are mostly limited to single sites and to binary morphological characters and they are very susceptible to missing data. Here we present GATRS (Gene Association in TRee Space), a novel algorithm than can operate on continuous morphological observations such as fin size and is robust to missing data by operating in gene tree space, analyzing linkages between entire genes and morphological traits. GATRS performs a large number of comparisons between closely related trees which requires a tree distance method that is particularly apt at distinguishing closely related …

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Sheehan Syndrome, Riya Jain, Shashidhara Kc, Savitha Savitha Jan 2019

Sheehan Syndrome, Riya Jain, Shashidhara Kc, Savitha Savitha

Digital Journal of Clinical Medicine

No abstract provided.

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Accelerating Data Accessing By Exploiting Flash Memory Technologies, Jing Yang Jan 2019

Accelerating Data Accessing By Exploiting Flash Memory Technologies, Jing Yang

Open Access Dissertations

Flash memory based SSD (solid state Drive) receives a lot of attention recently. SSD is a semiconductor device which provides great advantages in terms of high-speed random reads, low power consumption, compact size, and shock resistance. Traditional storage systems and algorithms are designed for hard disk drive (HDD), they do not work well on SSD because of SSD's asymmetric read/write performances and unavoidable internal activities, such as garbage collection (GC). There is a great need to optimize current storage systems and algorithms to accelerate data access in SSD. This dissertation presents four methods to improve the performance of the storage …

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What To Eat And When: The Consequences Of Polyunsaturated Fat Consumption And Pace Of Changes To Body Lipid Composition In Songbirds, Wales Aran Carter Jan 2019

What To Eat And When: The Consequences Of Polyunsaturated Fat Consumption And Pace Of Changes To Body Lipid Composition In Songbirds, Wales Aran Carter

Open Access Dissertations

Diet mediates environmental influence on organismal performance, but diets must be broken down into their constituent compounds and integrated into organismal tissues before they can exert such influence. Thus, a full account of the relationship between diet and organismal performance requires descriptions of intermediate effects on body composition and tissue function, as well as the dynamics of composition and function over time. The work described in this dissertation investigates a case study of diet and organismal performance in songbirds: dietary polyunsaturated fats have been demonstrated to influence the metabolic performance of songbirds, but the influence of individual fatty acid compounds, …

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Mindfulness In Legal Ethics And Professionalism, Peter H. Huang Jan 2019

Mindfulness In Legal Ethics And Professionalism, Peter H. Huang

Publications

Mindfulness involves paying attention with curiosity in an intentional, open, and compassionate way to life as it unfolds moment to moment. Law students, lawyers, law professors, legal clients, and indeed all people can improve their lives through mindfulness. Mindfulness can lead to individual benefits and personal transformation. Mindfulness can also lead to societal benefits and social change. This invited symposium contribution exemplifies how mindfulness can facilitate the positive personal and professional development of law students by presenting excerpts of law students’ answers discussing mindfulness to questions from the final examination of the course: Legal Ethics and Professionalism. Notably, none of …

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Future Of Scholarly Publishing And Scholarly Communication: Report Of The Expert Group To The European Commission, Directorate-General For Research And Innovation (European Commission), Jean-Claude Guédon, Jubb Consulting, United Kingdom, Bianca Kramer, Mikael Laakso, Birgit Schmidt, Elena Šimukovič, Jennifer Hansen, Robert Kiley, Anne Kitson, Wim Van Der Stelt, Kamilla Markram, Mark Patterson, Jan 2019

Future Of Scholarly Publishing And Scholarly Communication: Report Of The Expert Group To The European Commission, Directorate-General For Research And Innovation (European Commission), Jean-Claude Guédon, Jubb Consulting, United Kingdom, Bianca Kramer, Mikael Laakso, Birgit Schmidt, Elena Šimukovič, Jennifer Hansen, Robert Kiley, Anne Kitson, Wim Van Der Stelt, Kamilla Markram, Mark Patterson,

Copyright, Fair Use, Scholarly Communication, etc.

The Expert Group on the Future of Scholarly Publishing and Scholarly Communication was set up to support the policy development of the European Commission on Open Science. The Expert Group was asked to assess the current situation with regard to scholarly communication and publishing and to establish general principles for the future. This report analyses the recent past and present states of scholarly communication and publishing. It proposes ten principles through which a vision for scholarly communication is shaped over the next 10-15 years. These principles also serve as a way to examine shortcomings of the current scholarly communication and …

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Classification Of Generic System Dynamics Model Outputs Via Supervised Time Series Pattern Discovery, Mert Edali, Mustafa Gökçe Baydoğan, Gönenç Yücel Jan 2019

Classification Of Generic System Dynamics Model Outputs Via Supervised Time Series Pattern Discovery, Mert Edali, Mustafa Gökçe Baydoğan, Gönenç Yücel

Turkish Journal of Electrical Engineering and Computer Sciences

System dynamics (SD) is a simulation-based approach for analyzing feedback-rich systems. An ideal SD modeling cycle requires evaluating the qualitative pattern characteristics of a large set of time series model output for testing, validation, scenario analysis, and policy analysis purposes. This traditionally requires expert judgement, which limits the extent of experimentation due to time constraints. Although time series recognition approaches can help to automate such an evaluation, utilization of them has been limited to a hidden Markov model classifier, namely the Indirect Structure Testing Software (ISTS) algorithm. Despite being used within several automated model-analysis tools, ISTS has several shortcomings. In …

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A Kalman Filter Application For Rainfall Estimation Using Radar Reflectivity Measurements, Engi̇n Maşazade, Ali̇ Kemal Bakir, Pinar Kirci Jan 2019

A Kalman Filter Application For Rainfall Estimation Using Radar Reflectivity Measurements, Engi̇n Maşazade, Ali̇ Kemal Bakir, Pinar Kirci

Turkish Journal of Electrical Engineering and Computer Sciences

The rainfall amount observed at a given location mostly depend on the cloud density, which can be quantified with the reflectivity values observed by meteorology weather radars. In this study, we aim to estimate the rainfall amount using a Kalman filter with radar reflectivity measurements. We first assume that the amount of rainfall observed at automatic weather observation stations (AWOSs) are elements of an unknown state vector and consider the Kalman filter process model as the true rainfall amounts observed at these AWOSs over time. For the measurement model of the Kalman filter, we use the radar reflectivity values observed …

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A Hybrid Model For The Prediction Of Aluminum Foil Output Thickness In Cold Rolling Process, Ali̇ Öztürk, Ri̇fat Şeherli̇ Jan 2019

A Hybrid Model For The Prediction Of Aluminum Foil Output Thickness In Cold Rolling Process, Ali̇ Öztürk, Ri̇fat Şeherli̇

Turkish Journal of Electrical Engineering and Computer Sciences

This study proposes a hybrid model composed of multiple prediction algorithms and an autoregressive moving average (ARMA) module for the thickness prediction. In order to attain higher accuracy, the prediction algorithms were globally combined by simple voting to reduce the effect of the inductive bias imposed by each algorithm on the dataset. The global multiexpert combination (GMEC) system included the multilayer perceptron neural network (MLPNN), radial basis function network (RBFN), multiple linear regression (MLR), and support vector machines (SVM) algorithms. The proposed hybrid model extends the GMEC system by integrating an ARMA module for the output. On the test dataset, …

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Invisible Watermarking Framework That Authenticates And Prevents The Visualization Of Anaglyph Images For Copyright Protection, David-Octavio Muñoz-Ramirez, Volodymyr Ponomaryov, Rogelio Reyes-Reyes, Clara Cruz-Ramos, Beatriz-Paulina Garcia-Salgado Jan 2019

Invisible Watermarking Framework That Authenticates And Prevents The Visualization Of Anaglyph Images For Copyright Protection, David-Octavio Muñoz-Ramirez, Volodymyr Ponomaryov, Rogelio Reyes-Reyes, Clara Cruz-Ramos, Beatriz-Paulina Garcia-Salgado

Turkish Journal of Electrical Engineering and Computer Sciences

In this work, a watermarking framework to authenticate and protect the copyright that prevents the visualization of nonauthorized anaglyph images is proposed. Designed scheme embeds a binary watermark and the Blue channel of the anaglyph image into the discrete cosine transform domain of the original image. The proposed method applies the quantization index modulation-dither modulation algorithm and a combination of Bose-Chaudhuri-Hocquenghem with repetition codes, which permit to increase the capability in recovering the watermark. Additionally, Hash algorithm is used to scramble the component where the watermark should be embedding, guaranteeing a higher security performance of the scheme. This new technique …

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Ingan/Gan Tandem Solar Cell Parameter Estimation: A Comparative Stud, Abdelmoumene Benayad, Smail Berrah Jan 2019

Ingan/Gan Tandem Solar Cell Parameter Estimation: A Comparative Stud, Abdelmoumene Benayad, Smail Berrah

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, two hybrid estimation approaches, hybrid genetic algorithm (TR-GA) and hybrid particle swarm optimization (TR-PSO), are used to estimate single-diode model InGaN/GaN solar cell parameters from J?V experimental data under AM0 illumination. These parameters are photocurrent density ($J_{ph}$), reverse saturation current density ($J_{s}$), ideality factor ($A$), series resistance ($R_{s}$), and shunt resistance ($R_{sh}$). The trust region (TR) method used in both approaches provides the initial conditions and helps to avoid the problem of premature convergence (due to local minimum). Simulation results based on the minimization of the mean square error between experimental and theoretical J-V characteristics show that …

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A New Failure Protection Algorithm For Circuit Breakers Using The Power Loss Of Switching Arc Incidents, Behnam Feizifar, Ömer Usta Jan 2019

A New Failure Protection Algorithm For Circuit Breakers Using The Power Loss Of Switching Arc Incidents, Behnam Feizifar, Ömer Usta

Turkish Journal of Electrical Engineering and Computer Sciences

The principal function of circuit breakers (CBs) is to isolate a portion of the power network from the rest of it in a timely manner following an opening command. Any failure in the opening operation of CBs, especially following a fault condition, will almost certainly result in a catastrophic event. Therefore, the issue of failure detection of CBs is essential and has a vital role in power system protection. This paper presents a novel power-based algorithm for failure detection of CBs. The power loss of CBs due to an arcing event increases as the arcing time gets longer. The arcing …

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On Parameter Adjustment Of The Fuzzy Neighborhood-Based Clustering Algorithms, Fatma Günseli̇ Yaşar, Gözde Ulutagay, Semi̇h Utku, Efendi̇ Nasi̇boğlu Jan 2019

On Parameter Adjustment Of The Fuzzy Neighborhood-Based Clustering Algorithms, Fatma Günseli̇ Yaşar, Gözde Ulutagay, Semi̇h Utku, Efendi̇ Nasi̇boğlu

Turkish Journal of Electrical Engineering and Computer Sciences

Day by day huge amounts data are produced, and evaluation of these data becomes more difficult. The data obtained should provide meaningful, correct, and accurate information. Therefore, all data must be separated into clusters correctly, and the right information from these clusters must be obtained. Having the correct clusters depends on the clustering algorithm that is used. There are many clustering algorithms. The density-based methods are very important among the groups of clustering methods, as they can find arbitrary shapes. An advanced model of the density-based spatial clustering of applications with noise (DBSCAN) algorithm, called fuzzy neighborhood DBSCAN Gaussian means …

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Automatic Fault Isolation And Restoration Of Distribution System Using Jade Based Multi-Agents, Indhumathi Chellaswamy, Joy Vasantha Rani Sp Jan 2019

Automatic Fault Isolation And Restoration Of Distribution System Using Jade Based Multi-Agents, Indhumathi Chellaswamy, Joy Vasantha Rani Sp

Turkish Journal of Electrical Engineering and Computer Sciences

This paper proposes a solution for automatic service restoration along with automatic fault location and isolation of the faulty sections in feeder in a power distribution system. A Java agent development environment-based multiagent system (MAS) is proposed to solve the problem of automatic service restoration in smart grid distribution systems. The agent-based solution development is discussed in detail and the MAS application to solve power restoration problem is elaborated in this paper. A study is done on a modified IEEE 33 bus system and the solution is implemented in the Velachery substation of the Tamilnadu electricity board. The results prove …

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A Light-Weight Solution For Blackhole Attacks In Wireless Sensor Networks, Bi̇lal Erman Bi̇lgi̇n, Selçuk Baktir Jan 2019

A Light-Weight Solution For Blackhole Attacks In Wireless Sensor Networks, Bi̇lal Erman Bi̇lgi̇n, Selçuk Baktir

Turkish Journal of Electrical Engineering and Computer Sciences

Wireless sensors, which are smaller and cheaper, have started being used in many different applications. Military applications, health care and industrial monitoring, environmental applications, smart grids, and vehicular ad-hoc networks are some of the best known applications of wireless sensors. In some applications, especially military, environmental, and health care applications, it is required that the communication between sensor nodes be encrypted to achieve privacy and confidentiality. In this work, some modifications have been made to the ad-hoc on-demand distance vector routing protocol, mostly preferred in wireless sensor networks, to make data communications more reliable. The proposed routing protocol is shown …

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Patient Comfort Level Prediction During Transport Using Artificial Neural Network, Zeljko Jovanovic, Marija Blagojevic, Dragan Jankovic, Aleksandar Peulic Jan 2019

Patient Comfort Level Prediction During Transport Using Artificial Neural Network, Zeljko Jovanovic, Marija Blagojevic, Dragan Jankovic, Aleksandar Peulic

Turkish Journal of Electrical Engineering and Computer Sciences

Since patient comfort during transport is a matter of paramount importance, this paper aims to determine the possibilities of applying neural networks for its prediction and monitoring. Specific objectives of the research include monitoring and predicting patient transport comfort, with subjective assessment of comfort by medical personnel. An original Android application that collects signals from an accelerometer and a GPS sensor was used with the aim of achieving the research goals. The collected signals were processed and a total of twelve parameters were calculated. A multilayer perceptron was created in the proposed research. The evaluation results indicate acceptable accuracy and …

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Real-Time Implementation Of Electronic Power Transformer Based On Intelligentcontroller, Hakan Açikgöz, Ökkeş Fati̇h Keçeci̇oğlu, Mustafa Şekkeli̇ Jan 2019

Real-Time Implementation Of Electronic Power Transformer Based On Intelligentcontroller, Hakan Açikgöz, Ökkeş Fati̇h Keçeci̇oğlu, Mustafa Şekkeli̇

Turkish Journal of Electrical Engineering and Computer Sciences

Along with the rapid advances in power electronics and semiconductor technology, electronic power transformers (EPTs), which are expected to replace conventional power transformers in the future, are being developed and designed. This study presents the dynamic performance of the intelligent controller structure in the control of an EPT. The EPT structure, consisting of the input, isolation, and output stages, is designed for experimental and simulation studies. A three-phase pulse width modulation (PWM) rectifier is used to rectify the grid voltages at the input stage of EPT. The DC-bus voltage of the three-phase PWM rectifier is controlled by a neuro-fuzzy controller …

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Design Optimization Using Dielectric Slab For Efficient Microwave Heating, Sofiya Ali Mekonnen, Si̇bel Yeni̇kaya Jan 2019

Design Optimization Using Dielectric Slab For Efficient Microwave Heating, Sofiya Ali Mekonnen, Si̇bel Yeni̇kaya

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, usage of a dielectric slab on the top and bottom sides, on the top side, and on the bottom side of a clay sample was presented as a means of improving heating efficiency in multimode applicator. In order to accomplish the optimization procedure, we used four different dielectric slab types having different thickness values. The simulated results show that by using additional dielectric slab it is possible to increase the electric field intensity inside the applicator and obtain higher power absorption rates within the sample and high-efficiency designs.

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Limited-Data Automatic Speaker Verification Algorithm Using Band-Limitedphase-Only Correlation Function, Ángel Pedroza, José De La Rosa, José De Jesus Villa, Aldonso Becerra Jan 2019

Limited-Data Automatic Speaker Verification Algorithm Using Band-Limitedphase-Only Correlation Function, Ángel Pedroza, José De La Rosa, José De Jesus Villa, Aldonso Becerra

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a new method to deal with automatic speaker verification based on band-limited phaseonly correlation (BLPOC) is proposed. The aim of this study is to validate the use of the BLPOC function as a new limited-data automatic speaker verification technique. Although some speaker verification techniques have high accuracy, efficiency usually depends on the extraction of complex theoretical information from speech signals and the amount of the data for training the algorithms. The BLPOC function is a high-accuracy biometric technique traditionally implemented in human identification by fingerprints (through image-matching). When applying the BLPOC function in automatic speaker verification through …

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Fault-Tolerant Control Of A Pmsg-Based Wind Turbine Based On Parallelinterleaved Converters, Mohamed Abbes Jan 2019

Fault-Tolerant Control Of A Pmsg-Based Wind Turbine Based On Parallelinterleaved Converters, Mohamed Abbes

Turkish Journal of Electrical Engineering and Computer Sciences

Lowering the cost of wind energy has been one of the main objectives of the wind industry in the past years. To achieve this objective, considerable research efforts have been made to improve the availability of wind turbines. Recent statistical analyses have shown that frequency converters are among the most frequently failing components for variable speed wind systems. Therefore, several configurations were proposed in the literature to improve the availability of these generating devices. These configurations are mainly based on the redundancy of power converters (active and standby) or the converter bypass technique. However, for the special case of PMSG-based …

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Towards Wearable Blood Pressure Measurement Systems From Biosignals: A Review, Ümi̇t Şentürk, Kemal Polat, İbrahi̇m Yücedağ Jan 2019

Towards Wearable Blood Pressure Measurement Systems From Biosignals: A Review, Ümi̇t Şentürk, Kemal Polat, İbrahi̇m Yücedağ

Turkish Journal of Electrical Engineering and Computer Sciences

Blood pressure is the pressure by the blood to the vein wall. High blood pressure, which is called silent death, is the cause of nearly 13 % of mortality all over the world. Blood pressure is not only measured in the medical environment, but the blood pressure measurement is also a need for people in their daily life. Blood pressure estimation systems with low error rates have been developed besides the new technologies and algorithms. Blood pressure measurements are differentiated as invasive blood pressure (IBP) measurement and noninvasive blood pressure (NIBP) measurement methods. Although IBP measurement provides the most accurate …

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Performance Improvement Of Multiuser Cognitive Relay Networks With Full-Duplex Cooperative Sensing And Energy Harvesting, Alieh Moradi, Hamid Farrohki Jan 2019

Performance Improvement Of Multiuser Cognitive Relay Networks With Full-Duplex Cooperative Sensing And Energy Harvesting, Alieh Moradi, Hamid Farrohki

Turkish Journal of Electrical Engineering and Computer Sciences

Energy harvesting cognitive radio has been considered as a promising technology in the fifth generation (5G) of wireless networks to solve the lack of spectrum and energy. In this paper, a novel wireless energy harvesting relay network is proposed for a multiuser cognitive radio to obtain the maximum throughput and decrease the false alarm and misdetection probabilities. The secondary user (SU) can harvest energy from solar sources while utilizing the licensed spectrum of the primary user (PU). Cooperative spectrum sensing is applied to improve the performance of the secondary network and decrease collision and sensing time. In this paper, the …

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Hgab3c: A New Hybrid Global Optimization Algorithm, Kamaljeet Kaur, Shakti Kumar, Jyoti Saxena Jan 2019

Hgab3c: A New Hybrid Global Optimization Algorithm, Kamaljeet Kaur, Shakti Kumar, Jyoti Saxena

Turkish Journal of Electrical Engineering and Computer Sciences

This paper proposes a new optimization algorithm, namely HGAB3C, and presents its performance on the CEC-2014 test suite. In HGAB3C, simple genetic algorithms (GAs) and big bang-big crunch (BB-BC) are hybridized. The algorithm carries out global searches using a simple GA. In every generation the BB-BC algorithm is used to carry out local searches. The addition of local search has improved the capability of simple GAs significantly. The performance of the proposed algorithm is compared with 17 other optimization algorithms on all 30 functions of the CEC-2014 benchmark suite. It is observed that HGAB3C outperforms all other algorithms on 4 …

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Enhancing Face Pose Normalization With Deep Learning, Anil Çeli̇k, Nafi̇z Arica Jan 2019

Enhancing Face Pose Normalization With Deep Learning, Anil Çeli̇k, Nafi̇z Arica

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, we propose a hybrid method for face pose normalization, which combines the 3-D model-based method with stacked denoising autoencoder (SDAE) deep network. Instead of applying a mirroring operation for the invisible face parts of the posed image, SDAE learns how to fill in those regions by a large set of training samples. In the performance evaluation, we compare the proposed method to four different pose normalization methods and investigate their effects on facial emotion recognition and verification problems in addition to visual quality tests. Methods evaluated in the experiments include 2-D alignment, 3-D model-based method, pure SDAE-based …

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Extracting Accent Information From Urdu Speech For Forensic Speaker Recognition, Falak Tahir, Sajid Saleem, Ayaz Ahmad Jan 2019

Extracting Accent Information From Urdu Speech For Forensic Speaker Recognition, Falak Tahir, Sajid Saleem, Ayaz Ahmad

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a new method for extraction of accent information from Urdu speech signals. Accent is used in speaker recognition system especially in forensic cases and plays a vital role in discriminating people of different groups, communities and origins due to their different speaking styles. The proposed method is based on Gaussian mixture model-universal background model (GMM-UBM), mel-frequency cepstral coefficients (MFCC), and a data augmentation (DA) process. The DA process appends features to base MFCC features and improves the accent extraction and forensic speaker recognition performances of GMM-UBM. Experiments are performed on an Urdu forensic speaker corpus. The experimental …

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Sentence Similarity Using Weighted Path And Similarity Matrices, Reza Javadzadeh, Morteza Zahedi, Marziea Rahimi Jan 2019

Sentence Similarity Using Weighted Path And Similarity Matrices, Reza Javadzadeh, Morteza Zahedi, Marziea Rahimi

Turkish Journal of Electrical Engineering and Computer Sciences

Sentence similarity is the task of assessing how similar the two snippets of text are. Similarity techniques are used extensively in clustering, summarization, classification, plagiarism detection etc. Due to a small set of vocabularies, sentence similarity is considered to be a difficult problem in natural language processing. There are two issues in solving this problem: (1) Which similarity techniques to be used for word pair similarity and (2) How to generalize that to sentence pairs. We have used the weighted path, a WordNet-based similarity assessment, and the paraphrase database to obtain word pair similarity values. Thereafter, we extracted maximum values …

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Trmor: A Finite-State-Based Morphological Analyzer For Turkish, Ayla Kayabaş, Helmut Schmi̇d, Ahmet Ercan Topcu, Özkan Kiliç Jan 2019

Trmor: A Finite-State-Based Morphological Analyzer For Turkish, Ayla Kayabaş, Helmut Schmi̇d, Ahmet Ercan Topcu, Özkan Kiliç

Turkish Journal of Electrical Engineering and Computer Sciences

Morphological analysis is an important component of natural language processing systems like spelling correction tools, parsers, machine translation systems, and dictionary tools. In this paper, we present TRMOR, a morphological analyzer for Turkish, which uses the SFST tool (Stuttgart Finite-State Transducer). TRMOR can be freely used for academic research (see http://www.cis.uni-muenchen.de/~schmid/tools/SFST/). It covers a large part of Turkish morphology including inflection, derivation, and some compounding. It uses morphotactic and morphophonological rules and a stem lexicon. We describe the morphological structure of Turkish, explain the phonological and morphological rules implemented in TRMOR, evaluate the system, and test it in special cases. …

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Diffusive Representation Modelling Thermal And Overvoltage For Permanent Magnet Synchronous Motor Fed By Voltage Inverter, Khaled Ben Smida, Moncef Ben Smida, Brahim Mrabet Jan 2019

Diffusive Representation Modelling Thermal And Overvoltage For Permanent Magnet Synchronous Motor Fed By Voltage Inverter, Khaled Ben Smida, Moncef Ben Smida, Brahim Mrabet

Turkish Journal of Electrical Engineering and Computer Sciences

Life of electric machines is very sensitive to temperature increases especially due to the fragility of their windings as well as to the overvoltage at the motor's terminals. Therefore, it is necessary to find the temperature in the most sensitive areas of the machine. It has been known for a long time that temperature rise is caused by the losses in the machine; thus, various models have been proposed. It has also been shown that the permanent magnet synchronous motor fed by a voltage inverter overheats more than the one supplied by a sinusoidal voltage. Indeed the permanent magnet synchronous …

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An Improved Space Charge Distribution Analytical Model To Assess Field-Effect Transistor's Intrinsic Capacitors, Saif Ur Rehman, Umer Farooq Ahmed, Muhammad Mansoor Ahmed, Umair Rafique Jan 2019

An Improved Space Charge Distribution Analytical Model To Assess Field-Effect Transistor's Intrinsic Capacitors, Saif Ur Rehman, Umer Farooq Ahmed, Muhammad Mansoor Ahmed, Umair Rafique

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, an analytical model has been developed for improved assessment of Miller capacitors for high-frequency metal?semiconductor field-effect transistors. Depletion layer underneath the Schottky barrier gate has been divided into four distinct regions, and by evaluating the charges associated with each region, gate-to-source ($C_{GS}$) and gate-to-drain ($C_{GD}$) capacitors, {commonly known as Miller capacitors,} have been defined accordingly. Mathematical expressions have been developed both for the linear as well as for the saturation region. Miller capacitors and their variation as a function of applied bias have been assessed. It has been shown that the proposed technique offers better accuracy in …

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A Novel Method Based On Comparison Using Threshold Scale For Cfar Detectors Under Environments With Conditions Of Electromagnetic Interference, Milad Daneshvar, Naser Parhizgar, Pouria Salehi Jan 2019

A Novel Method Based On Comparison Using Threshold Scale For Cfar Detectors Under Environments With Conditions Of Electromagnetic Interference, Milad Daneshvar, Naser Parhizgar, Pouria Salehi

Turkish Journal of Electrical Engineering and Computer Sciences

Detection of a noisy signal is a complex process. Many radar systems are working in an environment where the signal processing parts cannot overcome the effects of interference sources due to their high power. These sources of conflict may completely erode the signal or may make a mistake in deciding. It may make the return of the echoes of the goals difficult. To solve this problem, the detector processor can use a new algorithm to estimate noise power and then can set the threshold in different positions of the cell under test. The proposed algorithm, by differentiating between homogeneous and …

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