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Voltage Control Of Self-Excited Induction Generator Using Genetic Algorithm, Dheeraj Joshi, Kanwarjit Singh Sandhu, Mahender Kumar Soni

Turkish Journal of Electrical Engineering and Computer Sciences

Self-excited induction generators (SEIG) are found to be most suitable candidate for wind energy conversion application required at remote windy locations. Such generators are not able to maintain the terminal voltage with load as, a literature survey reveals, the voltage profile falls sharply with load. In this paper an attempt has been made to improve the voltage profile of a self-excited induction generator. A new methodology based upon Genetic Algorithm (GA) is proposed to compute the steady state performance of the model including core loss branch. Further efforts are made to control the terminal voltage under loaded conditions. Simulated results …

Electronic Differential With Direct Torque Fuzzy Control For Vehicle Propulsion System, Kada Hartani, Mohamed Bourahla, Yahia Miloud, Mohamed Sekour

Turkish Journal of Electrical Engineering and Computer Sciences

We model an electronic differential that will offer the best vehicle stability on a curved road. The proposed traction system consists of two permanent magnet synchronous (PMS) machines that ensure the drive of two back-driving wheels. The contribution of each wheel to the advance of the vehicle is represented by an element conveying the accumulation of mechanical coupling. The proposed control structure is based on the direct torque fuzzy control for each wheel-motor. Different simulations have been carried out: vehicle driven ons straight road, vehicle driven on straight road with slope, and vehicle driven over a road curved left and …

Parameter Identification Of A Separately Excited Dc Motor Via Inverse Problem Methodology, Mounir Hadef, Mohamed Rachid Mekideche

Turkish Journal of Electrical Engineering and Computer Sciences

Identification is considered to be among the main applications of inverse theory and its objective for a given physical system is to use data which is easily observable, to infer some of the geometric parameters which are not directly observable. In this paper, a parameter identification method using inverse problem methodology is proposed. The minimisation of the objective function with respect to the desired vector of design parameters is the most important procedure in solving the inverse problem. The conjugate gradient method is used to determine the unknown parameters, and Tikhonov's regularization method is then used to replace the original …

Whole Rock And Mineral Chemistry Of Ultramafic-Mafic Cumulates From The Orhaneli (Bursa) Ophiolite, Nw Anatolia, Ender Sarifakioğlu, Hayretti̇n Özen, John A. Winchester

Turkish Journal of Earth Sciences

The Orhaneli ophiolite, situated in the western part of the İzmir-Ankara-Erzincan Suture Zone (İAESZ) and south of Bursa, exposes cumulates belonging to the mantle-crust transition zone. The Orhaneli ophiolite consists mainly of ultramafic cumulates and subordinate mafic cumulates. The basal cumulate sequence comprises dunites locally interlayered with chromitite levels. Above, dunitic cumulates, commonly interbanded with cumulate wehrlites, grade up into two pyroxene peridotites (cumulate lherzolites showing some transition to cumulate harzburgites in places). The observation of cumulate gabbroic thin layers intercalated with ultramafic cumulates at least three times suggests that the magma chamber was periodically replenished by basaltic liquids. Petrographic …

^{207}Pb-^{206}Pb, ^{40}Ar-^{39}Ar And Fission-Track Geothermochronology Quantifying Cooling And Exhumation History Of The Kaman-Kırşehir Region Intrusions, Central Anatolia, Turkey, Durmuş Boztuğ, Özlem Güney, Matt Heizler, Raymond J. Jonckheer, Marion Tichomirowa, Nazmi̇ Otlu

Turkish Journal of Earth Sciences

The Kaman-Kırşehir region intrusions were generated in a post-collisional extensional setting following Cenomanian-Turonian docking of an oceanic island arc, comprising the supra-subduction zone (SSZ) Central Anatolian ophiolite (CAO), onto the Tauride-Anatolide Platform (TAP). These granitoids have been named, from N to S, the Çamsarı quartz syenite, Hamit quartz syenite, Bayındır nepheline-cancrinite syenite, Durmuşlu nepheline-nosean-melanite syenite porphyry and Baranadağ quartz monzonite. They intrude the crustal metasediments of the Central Anatolian Crystalline Complex (CACC) and CAO and are unconformably overlain by Upper Paleocene to Lower-Middle Eocene sediments. The single-zircon ^{207}Pb-^{206}Pb evaporation age of the Çamsarı unit is 95.7±5.1 Ma; those of the …

Bedrock Depth Mapping Of The Coast South Of İstanbul: Comparison Of Analytical And Experimental Analyses, Gülüm Bi̇rgören, Oğuz Özel, Bi̇lge Si̇yahi̇

Turkish Journal of Earth Sciences

Local S-wave velocity-depth profiles and bedrock depth distribution are key factors in assessing seismic hazard and earthquake ground motion characteristics since they allow determination of the amplification potential of geological formations overlying bedrock. In this study, an empirical relationship between the thickness of Tertiary-Quaternary sediments (hereafter referred as cover) overlying Palaeozoic bedrock and their resonance frequencies was calculated for the İstanbul region and the bedrock depth distribution beneath the city was presented. The relationship was investigated by comparing transfer functions obtained from single station microtremor analyses and one-dimensional (1D) S-wave velocity profiles at sites where shallow velocity structure is known. …

Cross-Basin Faulting And Extinction Of Pull-Apart Basins In The Sea Of Marmara, Nw Turkey, İsmai̇l Kuşçu

Turkish Journal of Earth Sciences

Although offshore multi-channel seismic reflection and multi-beam bathymetric studies were intensively carried out in the Sea of Marmara especially after the August 17, 1999 İzmit earthquake (Mw 7.4), some basic problems remain unsolved, for example whether the seafloor was cut by a double fault system or just by a single fault. The researchers advocating the double fault system assumed that most of the deformation occurred along the margins of the basins and concluded that the classical model of pull-apart basin formation along releasing bends or stepovers within an east−west-trending dextral strike-slip system prevails. An alternative and completely different proposition proposed …

Crustal Thermal Properties Of The Central Pontides (Northern Turkey) Deduced From Spectral Analysis Of Magnetic Data, Nafi̇z Maden

Turkish Journal of Earth Sciences

The Pontides can be divided tectonically into three main sectors: Eastern, Central, and Western Pontides. Each of these represents an amalgamated tectonic mosaic consisting of remnants of oceanic, continental, and island arc segments. The Eastern and the Western Pontides meet in the Central Pontides, where they are structurally mixed and form a tectonic knot. The Central Pontides of northern Turkey is one of the best exposed segments of the southern margin of Eurasia adjacent to the Tethys Ocean. The study area also extends to parts of the Sakarya and Kırşehir continents. Magnetic spectral analysis, which has been used to estimate …

Permian Trilobites From Antalya Province, Turkey, And Enrollment In Late Palaeozoic Trilobites, Rudy Lerosey Aubril, Lucia Angiolini

Turkish Journal of Earth Sciences

Trilobites are a minor component of Permian benthic marine faunas, which explains why they remain poorly known. For example, only two specimens have been found in the highly fossiliferous and extensively studied Middle-Upper Permian Pamucak Formation (Antalya Province, Turkey). These two complete enrolled trilobites of Wordian age are described herein. The diagnosis of the subgenus Pseudophillipsia (Nodiphillipsia) Kobayashi & Hamada 1984a is emended and its occurrence outside of eastern Asia is reported for the first time. The second specimen represents a new species, Pseudophillipsia (Carniphillipsia) kemerensis sp. nov. Its discovery in the Wordian of Turkey suggests that Pseudophillipsia (Carniphillipsia) is …

Geochemical And Mineralogical Characteristics Of Fe-Ni Laterite Ore Of Sarıçimen (Çaldıran-Van) Area In Eastern Anatolia, Turkey, Ali̇ Riza Çolakoğlu

Turkish Journal of Earth Sciences

The Sarıçimen Fe-Ni laterite ore is located 15 km east of Çaldıran County, northeast of Lake Van. This area is situated in the eastern Anatolia accretionary complex of Turkey, close to the Iran boundary. It is the first transported Fe-Ni rich laterite to be described from this area. This paper concentrates on the mineralogical and textural features of the ore minerals and the transported Fe-Ni laterite zone. These transported laterites are very inhomogeneous and contain very abundant zoned chromite grains, which have been altered to magnetite. SEM/probe investigations indicate that Fe-Ni is depleted in the core chromite and increases in …

Optically Stimulated Luminescence To Date Coastal Dunes And A Possible Tsunami Layer On The Kavak Delta (Saros Gulf, Nw Turkey), Ahmet Evren Ergi̇nal, Nafi̇ye Kiyak Güneç, Hasan Özcan

Turkish Journal of Earth Sciences

Optically stimulated luminescence (OSL) dating was used to determine the timing of initial dune formation and reconstruct the evolution of coastal dunes that developed on the Kavak Delta, Saros Gulf, Turkey. Along a 500-m-long representative transect, dune sands were extracted from foredune, semistable (grey) dune, stable (dark) dune and dune-swamp boundary defined by a scarp 50-75 cm high. The data obtained showed that dune drift initiated 670 years ago. A pumice layer 15-20-cm-thick interbedded with marine clay and sand showed an OSL age of 340 years coinciding with underlying dune sand. XRF analysis showed that pumices were of similar composition …

First Record Of Crassostrea Cyathula Lamarck 1806 From �The Rupelian-Lower Chattian Of Sarıbuğday-Kovancılar� (Ne Palu) Eastern Taurids, E Turkey, İzzet Hoşgör, Yavuz Okan

Turkish Journal of Earth Sciences

Crassostrea cyathula (Lamarck 1806), a valuable biostratigraphic marker, was found for the first time in eastern Turkey (Eastern Mediterranean), in the Rupelian-Lower Chattian sedimentary sequences of northeastern Palu, Elazığ region, and its palaeoecological characters, palaeobiogeographic and stratigraphic distribution are discussed. These oyster specimens are also the first abundant macrofossils from the Oligocene sediments of the Sarıbuğday-Kovancılar section, which were formerly only recorded by micropalaeontological data.

Minerals From Macedonia. Xx. Geological Setting, Lithologies, And Identification Of The Minerals From Rzanovo Fe-Ni Deposit, Blazo Boev, Gligor Jovanovski, Petre Makreski

Turkish Journal of Earth Sciences

The Rzanovo deposit lies within the western ophiolite belt of the Vardar zone. Its main geological units are discussed in terms of their mineralogy, petrology and petrological evolution. Minerals observed include: magnetite, hematite, clinochlore, talc, sepiolite, magnesioriebeckite, lizardite, dolomite, phlogopite, stilpnomelane, quartz, albite, pyrite, maghemite, pyrrhotine, digenite and millerite. Some minerals had non-distinct morphologies and ambiguous characteristics, preventing identification on the basis of physical properties alone. Thus, some of the minerals (magnetite, hematite, talc, dolomite, olivine, calcite, aragonite and brucite) as well as some serpentine minerals (antigorite and chrysotile) were identified by vibrational spectroscopy. Difficulties in identification by IR spectroscopy …

Studies On Physical Properties And Carrier Conversion Of Sno_2:Nd Thin Films, Jochan Joseph, Varghese Mathew, Jacob Mathew, K. E. Abraham

Turkish Journal of Physics

Neodymium (Nd)-doped SnO_2 transparent conducting oxide thin films were prepared by vapour deposition technique under different deposition parameters: substrate temperature, time and flow rate of vapour deposition, amount of base material, distance between the substrate and spray gun tip, and dopant (Nd) concentration. The structural, optical, electrical and photo-electronic properties of the doped and undoped SnO_2 films were studied. X-ray diffraction studies shows the polycrystalline nature of the films with preferential orientation along the (101), (211) and (301) planes and an average grain size of 100 Å. The optical properties of these films were studied by measuring their optical transmission …

Effective Annealing Of Zno Thin Films Grown By Electrochemical Deposition Technique, Cevdet Coşkun, Harun Güney, Emre Gür, Sebahatti̇n Tüzemen

Turkish Journal of Physics

Wide and direct band gap ZnO thin films have been grown on conductive indium-tin-oxide (ITO) substrates by electrochemical deposition (ECD) technique using different growth parameters. High quality films in terms of crystallographic and optical characteristics have been obtained under a cathodic potential of -0.9 V; a pH of 5.2, using 0.1 M Zn(NO_3)_2 solution. Oxygen gas flow through the solution increased the growth rate and the quality of samples. Subsequent heat treatments at various temperatures for 30 minutes under dry N_2 gas flow show that the most suitable annealing temperature is 300 °C for these electrochemically deposited thin films on …

Kantowski-Sachs Viscous Fluid Cosmological Model With A Varying \Lambda, Sharad Kandalkar, Pramod Khade, Sunita Gawande

Turkish Journal of Physics

We study the Kantowski-Sachs cosmological model filled with viscous fluid in the presence of cosmological term \Lambda. To get a deterministic solution, a condition between metric potentials is used. The viscous coefficient of bulk viscous fluid is assumed to be a power function of mass density, whereas coefficient of shear viscosity is considered proportional to scale of expansion in the model. It is found that the cosmological constant \Lambda is positive and is a decreasing function of time, which is supported by results from recent supernova observations. Some physical and geometrical properties of the models are also discussed.

Tilted Bianchi Type I Dust Fluid Magnetized Cosmological Model In General Relativity, Anita Bagora, Ghanshyam Singh Rathore, Pushpa Bagora

Turkish Journal of Physics

Tilted Bianchi Type I perfect fluid cosmological model in presence of magnetic field is investigated. To get a determinate solution, we assume p = 0 and A = BC, where A, B and C are metric potentials. A special model is also investigated in the absence of magnetic field. The various physical and geometrical aspects of both the models are also discussed. The effect of the magnetic field on the model is also discussed.

On Some Properties Of The Neutrino In The Early Universe, S. Mani, A. Sagari, B. Chakrabarti, A. Bhattacharya

Turkish Journal of Physics

Properties of the neutrino in the early universe have been investigated incorporating a small inhomogeneity in the mass density of the early universe. Dependence on this factor is found in studying mean free path and mass bound of neutrinos. The mass bound of neutrino is found to be in the range between 14 MeV and 76 MeV corresponding to the radiation and matter dominated eras respectively. The oscillation length for neutrinos have been estimated to be 86 km for beam energy 2.754 MeV and 220 km for beam energy 7 MeV.

Cover And Contents

Turkish Journal of Zoology

No abstract provided.

Cover And Contents

Turkish Journal of Zoology

No abstract provided.

Temporal And Spatial Changes Of Crustaceans In Mixed Eelgrass Beds, Zostera Marina L. And Z. Noltii Hornem., At The Sinop Peninsula Coast (The Southern Black Sea, Turkey), Melek Ersoy Karaçuha, Murat Sezgi̇n, Ertan Dağli

Turkish Journal of Zoology

This research was carried out to determine the macrobenthic crustacean species associated with mixed eelgrass beds (Zostera marina and Z. noltii) occurring in the upper-infralittoral zone of the Sinop peninsula coast (the southern Black Sea, Turkey) and their bioecolological features. From June 2004 to April 2005, investigations were seasonally performed at the depths of 2-4 m at 6 different stations chosen on the Sinop peninsula coast. As a result of the study, a total of 7057 individuals belonging to 55 species and 6 orders were identified. Amphipoda was the dominant group in terms of number of species (63% of the …

Cover And Contents

Turkish Journal of Zoology

No abstract provided.

The Relation Between Gleason Score, And Nuclear Size And Shape Factors In Prostatic Adenocarcinoma, Si̇bel Bektaş, Burak Bahadir, Banu Doğan Gün, Gürkan Kerti̇ş, Şükrü Oğuz Özdamar

Turkish Journal of Medical Sciences

Aim: The aim of this study was to assess the size and shape characteristics of prostatic adenocarcinoma cell nuclei using a computer-assisted analysis system, and to compare the results with the Gleason score. Materials and Methods: Morphometric nuclear parameters, such as roundness factor, form ellipse, area, length, and perimeter, were evaluated based on specimen slides of 130 prostatic adenocarcinoma cases (77% needle biopsies and 23% prostatectomy specimens) using a computerized image analysis system. Correlation analysis between Gleason score and morphometric results was performed. Results: The Gleason score was correlated with mean nuclear area (r = 0.516, P = 0.01), mean …

Phellinus Sulphurascens (Hymenochaetaceae, Basidiomycota): A Very Rare Wood-Decay Fungus In Europe Collected In Turkey, Hasan Hüseyi̇n Doğan, Mitko Karadelev

Turkish Journal of Botany

Phellinus sulphurascens Pilát was collected from juniper tree stumps (Juniperus excelsa and J. foetidissima) in two different localities situated in the Mediterranean region of Turkey. This very rare species is known in Europe only from the Ural Mountains in Russia. This fungus is an aggressive root rot pathogen associated with Douglas fir and other conifers in North America. This is the first report on juniper as a new host outside of its known distribution area.

Prediction Of Light Gas Composition In Coal Devolatilization, Ravichandra S. Jupudi, Vladimir Zamansky, Thomas H. Fletcher

Faculty Publications

The chemical percolation devolatilization (CPD) model describes the devolatilization behavior of rapidly heated coal based on the chemical structure of the coal. It predicts the overall char, tar, and light gas yields. This paper presents an improved CPD model with improved capability for predicting light gas composition. This is achieved by incorporating a kinetic model that simulates the release of various light gas species from their respective sources/functional groups in coal. The improved CPD model is validated using experiments with a wire mesh reactor and published experimental observations

Flame Interactions And Burning Characteristics Of Two Live Leaf Samples, Brent M. Pickett, Carl Isackson, Rebecca Wunder, Thomas H. Fletcher, Bret W. Butler, David R. Weise

Faculty Publications

Combustion experiments were performed over a flat-flame burner that provided the heat source for multiple leaf samples. Interactions of the combustion behavior between two leaf samples were studied. Two leaves were placed in the path of the flat-flame burner, with the top leaf 2.5 cm above the bottom leaf. Local gas and particle temperatures, as well as local oxygen concentrations, were measured along with burning characteristics of both leaves. Results showed that the time to ignition of the upper leaf was not significantly affected by the presence of the lower leaf. The major difference observed was that the time of …

The Need For Ecumenical, Denominational And Empirically-Supported Christian Psychotherapy Approaches In Public Settings, P. Scott Richards

Faculty Publications

James Skillen has written an important and broad- ranging article about the place of Christian counseling in public settings. I will focus my brief comments on what I regard as some of the implications of the following statement: "You ought to be able to conduct your counseling and psychiatric practices in a thoroughly Christian manner within a public or semi-public accrediting system that provides public-legal protection and equal access for a diverse range of professional and disciplinary approaches. You should not have to stuff your practice into a private box if it is distinctively Christian any more than another professional …

A Distribution-Free Convolution Model For Background Correction Of Oligonucleotide Microarray Data, Zhongxue Chen, Monnie Mcgee, Qingzhong Liu, Megan Kong, Youping Deng, Richard H. Scheuermann

Faculty Publications

Introduction

Affymetrix GeneChip^® high-density oligonucleotide arrays are widely used in biological and medical research because of production reproducibility, which facilitates the comparison of results between experiment runs. In order to obtain high-level classification and cluster analysis that can be trusted, it is important to perform various pre-processing steps on the probe-level data to control for variability in sample processing and array hybridization. Many proposed preprocessing methods are parametric, in that they assume that the background noise generated by microarray data is a random sample from a statistical distribution, typically a normal distribution. The quality of the final results depends …

The Effect Of Weekly Teacher Collaboration On Instructional Practices In The Classroom, Laurene A. Lanich

Dissertations and Theses @ UNI

The Iowa Standards for School Leaders states that, “A principal is an educational leader who promotes the success of all students by advocating, nurturing, and sustaining a school culture and instructional program that is conducive to student learning and professional growth.” Instructional practices have a significant impact on student learning, with research indicating that effective teaching accounts for two thirds of the total effect of schooling on student learning. Moreover, the literature on school improvement and professional development emphasizes the building of organizational capacity through collegial interactions in school (Leonard & Leonard, 2003).

The Iowa Professional Development Model was developed …

Secondary Preservice Teachers' Understanding Of Euclidean Geometry, Karen Sabey

Dissertations and Theses @ UNI

The lack of mathematical understanding of elementary preservice teachers with respect to many mathematical topics has been well documented. Far fewer studies have been conducted on any content area of knowledge of secondary teachers and even less in the mathematics content area. The assumption by the general population is that mathematics majors are adequately prepared to teach the content of secondary mathematics because they major in mathematics. Mathematics educators, however, note the lack of conceptual understandings in many content areas in these mathematics teaching majors. While mathematics educators are aware of this deficiency, there is little research data at the …