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Magma Interaction Processes Inferred From Fe-Ti Oxide Compositions In The Dölek And Sarıçiçek Plutons, Eastern Turkey, Orhan Karsli, Faruk Aydin, İbrahi̇m Uysal, M. Burhan Sadiklar
Magma Interaction Processes Inferred From Fe-Ti Oxide Compositions In The Dölek And Sarıçiçek Plutons, Eastern Turkey, Orhan Karsli, Faruk Aydin, İbrahi̇m Uysal, M. Burhan Sadiklar
Turkish Journal of Earth Sciences
Magnetite-ulvöspinel and ilmenite-hematite solid solution intergrowths from the high-K calc-alkaline Dölek and Sarıçiçek plutons, Eastern Turkey, were investigated using microprobe analyses. Compositions of twenty-eight samples from the host rocks and their enclaves in the plutons were used to estimate the oxygen fugacity and temperature. The ilmenite and ulvöspinel component exsolves out along certain preferred crystallographic planes in the titanomagnetite of the host rocks, while they are always absent in those of the mafic microgranular enclaves. The titanomagnetite and ilmenite show variations as Mt_{98-70}Usp_{02-30} and Ilm_{99-65}Hm_{01-35} in composition, respectively. Estimations of oxygen fugacity and temperature using the titanomagnetite-ilmenite thermometry/oxygen barometry range …
Cretaceous Pelagic Red Beds And Black Shales (Aptian-Santonian), Nw Turkey: Global Oceanic Anoxic And Oxic Events, İsmai̇l Ömer Yilmaz
Cretaceous Pelagic Red Beds And Black Shales (Aptian-Santonian), Nw Turkey: Global Oceanic Anoxic And Oxic Events, İsmai̇l Ömer Yilmaz
Turkish Journal of Earth Sciences
The study areas located near the towns of Göynük, Mudurnu and Nallıhan in the central northwestern part of Turkey lie on the `Sakarya Continent´, which is one of the tectonic entities of the Cretaceous geology of Turkey. Measured stratigraphic sections comprise the Aptian pelagic carbonates and the overlying Albian-Coniacian turbiditic sequences, which are all capped by a Late Santonian red pelagic succession. Lower and Upper Aptian, Upper Albian and Cenomanian/Turonian marine black shales recognized in the sections are followed by Lower and Upper Aptian, Upper Albian and Turonian marine red beds. The black shales are generally silty, laminated, and include …
Electronic And Structural Properties Of Zincblende B_Xga_{1-X}N, Abdelhadi Lachebi, Hamza Abid
Electronic And Structural Properties Of Zincblende B_Xga_{1-X}N, Abdelhadi Lachebi, Hamza Abid
Turkish Journal of Physics
We present structural and electronic properties of the cubic structure for different concentrations x of ternary alloy B_xGa_{1-x}N. The computational method is based on the full-potential linearised augmented plane wave method (FP-LAPW). The exchange and correlation energy is described in the local density approximation (LDA) and generalized gradient approximation (GGA). We have investigated the effect of composition on the ground state properties, lattice parameters, bulk modulus, pressure derivative and band gap of the zinc blend BN and GaN. The results obtained are in a good agreement with experimental and theoretical values concerning the variation of the gaps and crossover direct, …
The Electrical Resistance Of Mo_{0.5}W_{0.5}S_2 Single Crystal Under Pressure, A. K. Shah, P. N. Gajjar
The Electrical Resistance Of Mo_{0.5}W_{0.5}S_2 Single Crystal Under Pressure, A. K. Shah, P. N. Gajjar
Turkish Journal of Physics
Single crystals of Mo_{0.5}W_{0.5}S_2 were grown by chemical vapour transport and direct vapour transport techniques. The crystals have been characterized by X-ray energy dispersive analysis and X-ray powder diffraction. The dc electrical resistance of the grown single crystals of Mo_{0.5}W_{0.5}S_2 was measured in Bridgman anvil set-up to 8 GPa to identify occurrence of structural phase transitions. The drastic changes in electrical resistance were observed at \sim2.5 GPa and \sim4.6 GPa, and are similar to the structural phase transitions in WS_2 single crystals.
Cover And Contents
Turkish Journal of Veterinary & Animal Sciences
No abstract provided.
Cover And Contents
Turkish Journal of Veterinary & Animal Sciences
No abstract provided.
Studies On The Chemical Constituents Of Thymus Serpyllum, Shahid Aziz, . Habib-Ur-Rehman
Studies On The Chemical Constituents Of Thymus Serpyllum, Shahid Aziz, . Habib-Ur-Rehman
Turkish Journal of Chemistry
Phytochemical investigations on the methanolic extract of Thymus serpyllum resulted in the isolation of 2 new compounds, 3-ketopentatriacontanoic acid (1) and 27-ketotriacontanol (2). The extract also afforded 3 known compounds, 3 \beta-hydroxyolean-12-en- 28-oic acid (3), 3-O-\beta-D-glucopyranosyl-sitosterol (4), and dihydroursonic acid (5), detected for the first time from Thymus serpyllum. The structures of the new compounds were elucidated by spectroscopic methods, while the known compounds were identified on the basis of their spectral data and literature evidence. The hexane and ethyl acetate soluble portions of the methanolic extract showed significant antifungal activity, whereas the chloroform soluble portion and the remaining methanol …
My Collaboration With Raj Mittra: Contributions To The Theory Of Perfectly Matched Layers, Mustafa Kuzuoğlu
My Collaboration With Raj Mittra: Contributions To The Theory Of Perfectly Matched Layers, Mustafa Kuzuoğlu
Turkish Journal of Electrical Engineering and Computer Sciences
No abstract provided.
Use Of Characteristic Basis Function Method For Scattering From Terrain Profiles, Atacan Yağbasan, Celal Alp Tunç, Vakur B. Ertürk, Ayhan Altintas, Raj Mittra
Use Of Characteristic Basis Function Method For Scattering From Terrain Profiles, Atacan Yağbasan, Celal Alp Tunç, Vakur B. Ertürk, Ayhan Altintas, Raj Mittra
Turkish Journal of Electrical Engineering and Computer Sciences
An integral equation (IE) based solution procedure is presented for the rigorous analysis of scattering from terrain profiles. The procedure uses characteristic basis function method (CBFM), which is hybridized with the forward-backward method (FBM), to reduce the storage requirements of the resultant Method of Moments (MoM) impedance matrix, as well as to accelerate the solution procedure. Numerical results in the form of induced current and scattered field are presented to assess the accuracy and efficiency of the solution procedure.
The Characteristic Basis Function Method (Cbfm): A Numerically Efficient Strategy For Solving Large Electromagnetic Scattering Problems, Eugenio Lucente, Gianluigi Tiberi, Agostino Monorchio, Giuliano Manara, Raj Mittra
The Characteristic Basis Function Method (Cbfm): A Numerically Efficient Strategy For Solving Large Electromagnetic Scattering Problems, Eugenio Lucente, Gianluigi Tiberi, Agostino Monorchio, Giuliano Manara, Raj Mittra
Turkish Journal of Electrical Engineering and Computer Sciences
The objective of this paper is to describe a numerically efficient strategy for solving large electromagnetic scattering problems. This novel approach, termed as the Characteristic Basis Function Method (CBFM), is based on utilizing Characteristic Basic Functions (CBFs)-special functions defined on macro domains (blocks)-that include a relatively large number of conventional sub-domains discretized by using triangular or rectangular patches. The CBFs can be derived either analytically (from PO solutions), or by applying the conventional MoM. Use of these basis functions leads to a significant reduction in the number of unknowns, and results in a substantial size reduction of the MoM matrix. …
Analysis And Optimization Of Mobile Phone Antenna Radiation Performance In The Presence Of Head And Hand Phantoms, Erdem Ofli, Chung-Huan Li, Nicolas Chavannes, Niels Kuster
Analysis And Optimization Of Mobile Phone Antenna Radiation Performance In The Presence Of Head And Hand Phantoms, Erdem Ofli, Chung-Huan Li, Nicolas Chavannes, Niels Kuster
Turkish Journal of Electrical Engineering and Computer Sciences
A commercial clam shell phone CAD model is used to numerically investigate the effect of a hand phantom on mobile phone antenna radiation performance. The simulation results show that the grip of the hand phantom is the most important parameter to antenna performance. The antenna is converted into a parameterized form, then optimized to achieve the targeted multi-band performance in real-usage conditions.
Dual-Band Split-Ring Antenna Design For Wlan Applications, S. Cumhur Başaran, Yunus E. Erdemli̇
Dual-Band Split-Ring Antenna Design For Wlan Applications, S. Cumhur Başaran, Yunus E. Erdemli̇
Turkish Journal of Electrical Engineering and Computer Sciences
A dual-band microstrip antenna based on split-ring elements is introduced for WLAN (2.4/5.2 GHz) applications. The proposed split-ring antenna (SRA) has a compact novel design which provides about 2% impedance-bandwidth without a need for additional matching network. Analysis and design of the proposed microstrip antenna is carried out by means of full-wave simulators based on the finite-element method.
Comparison Of Rectangular And Cylindrical Fdtd Representations On A Ring Resonator Problem, Funda Akleman, Levent Sevgi̇
Comparison Of Rectangular And Cylindrical Fdtd Representations On A Ring Resonator Problem, Funda Akleman, Levent Sevgi̇
Turkish Journal of Electrical Engineering and Computer Sciences
The aim of this paper is to discuss rectangular and cylindrical representations of finite-difference time-domain (FDTD) method over characteristic tests and comparisons. A ring resonator is chosen as a canonical structure and modeled with both rectangular- and cylindrical-FDTD packages. Calibration against analytical exact solution derived in terms of cylindrical Bessel functions is also performed. It is shown that rectangular-FDTD with periodic boundary condition, where the computation domain is reduced, can also be applied in modeling circular structures.
Cover And Contents
Turkish Journal of Electrical Engineering and Computer Sciences
No abstract provided.
Method Of Moments Solution By Using Sinc-Type Basis Functions For The Scattering From A Finite Number Of Conducting Strip Gratings, Taner Oğuzer, Fadil Kuyucuoğlu
Method Of Moments Solution By Using Sinc-Type Basis Functions For The Scattering From A Finite Number Of Conducting Strip Gratings, Taner Oğuzer, Fadil Kuyucuoğlu
Turkish Journal of Electrical Engineering and Computer Sciences
A numerical method of moments (MoM) solution is applied to the electromagnetic scattering from a periodic finite conducting strip array when the incident electromagnetic plane wave E and H polarizations illuminate the grating. For such grating strip geometry, we deal with singular integral equations arising from Neumann and Dirichlet boundary conditions. MoM is applied using band-limited sinc functions as basis and testing functions. The Galerkin approach is followed in MoM formulation. The properties of the sinc function, with the infinite integral, are exploited in the computations of the main matrix elements. Also, the error in our approach goes to zero …
Comparison Of Basic Linear Filters In Extracting Auditory Evoked Potentials, Serap Aydin
Comparison Of Basic Linear Filters In Extracting Auditory Evoked Potentials, Serap Aydin
Turkish Journal of Electrical Engineering and Computer Sciences
In the present study, the performances of two well-known linear filtering techniques are compared for extraction of auditory Evoked Potential (EP) from a relatively small number of sweeps. Both experimental and simulated data are filtered by the two algorithms into two groups. Group A consists of Wiener filtering (WF) applications, where conventional WF and Coherence Weighted WF (CWWF)) have been assessed in combination with the Subspace Method (SM). Group B consists of the well-known adaptive filtering algorithms Least Mean Square (LMS), Recursive Least Square (RLS), and one-step Kalman filtering (KF). Both groups are tested with respect to signal-to-noise ratio (SNR) …
Zero Crossing Counter For Accuracy Improvement Of Fmcw Range Detection, Si̇nan Kurt, Şi̇mşek Demi̇r, Altunkan Hizal
Zero Crossing Counter For Accuracy Improvement Of Fmcw Range Detection, Si̇nan Kurt, Şi̇mşek Demi̇r, Altunkan Hizal
Turkish Journal of Electrical Engineering and Computer Sciences
For civil and military purposes FMCW radars are widely used. The theoretical background is well-established. Nevertheless, improvement of various aspects of these radars is still required. Signal processing is one of the crucial points of the system which determines the capabilities of the radar. In this study a zero crossing detector implementation, which can be efficiently used for target detection and range calculation in short range FMCW range detector is proposed. The duration between consecutive zero-crossings are used as the data instead of the number of cycles per unit time. Experimental evaluation of its performance is also given.
Online Tuning Of Set-Point Regulator With A Blending Mechanism Using Pi Controller, Engi̇n Yeşi̇l, Müjde Güzelkaya, İbrahi̇m Eksi̇n, Ö. Aydin Teki̇n
Online Tuning Of Set-Point Regulator With A Blending Mechanism Using Pi Controller, Engi̇n Yeşi̇l, Müjde Güzelkaya, İbrahi̇m Eksi̇n, Ö. Aydin Teki̇n
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, a new control structure that exploits the advantages of one degree of freedom (1-DOF) and two degree of freedom (2-DOF) control structures with an online tuned set-point regulator with blending mechanism (SPR-BM) is proposed. In this structure, the filtered output of the reference and the pure reference signals are blended so that the overall performance of the system is ameliorated with respect to load disturbance rejection and set-point following. Internal Model Control (IMC) based PI controller is used as the primary controller and the blending dynamics are determined with the aim of producing a system output that …
A New Approach Using Temporal Radial Basis Function In Chronological Series, Mustapha Guezouri
A New Approach Using Temporal Radial Basis Function In Chronological Series, Mustapha Guezouri
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, we present an extended form of Radial Basis Function network called Temporal-RBF (T-RBF) network. This extended network can be used in decision rules and classification in Spatio-Temporal domain applications, like speech recognition, economic fluctuations, seismic measurements and robotics applications. We found that such a network complies with relative ease to constraints such as capacity of universal approximation, sensibility of node, local generalisation in receptive field, etc. For an optimal solution based on a probabilistic approach with a minimum of complexity, we propose two TRBF models (1 and 2). Application to the problem of Mackey-Glass time series has …
Cover And Contents
Turkish Journal of Electrical Engineering and Computer Sciences
No abstract provided.
Role Of Artificial Intelligence In The Reliability Evaluation Of Electric Power Systems, Chanan Singh, Lingfeng Wang
Role Of Artificial Intelligence In The Reliability Evaluation Of Electric Power Systems, Chanan Singh, Lingfeng Wang
Turkish Journal of Electrical Engineering and Computer Sciences
Every reliability analysis effort, in some way, involves searching the state space of the system for those states that represent the events of interest, typically failure of the system or a given node to meet the demand. This essentially translates into a search procedure to efficiently identify states to be examined and then using a mechanism to evaluate these states. Traditionally, reliability analysis methods are based either on an implicit or explicit enumeration process or Monte Carlo sampling. More recently, methods based on artificial intelligence have been investigated both as an alternative to Monte Carlo for the search process as …
Dispersion Analysis Of The Adi-Fdtd And S-Fdtd Methods, Mehmet Kuşaf, Abdullah Y. Öztoprak
Dispersion Analysis Of The Adi-Fdtd And S-Fdtd Methods, Mehmet Kuşaf, Abdullah Y. Öztoprak
Turkish Journal of Electrical Engineering and Computer Sciences
Numerical dispersion performances of ADI-FDTD and S-FDTD methods have been compared. It has been shown that for time steps below the stability limits of the S-FDTD method it has much better dispersion performance compared with the ADI-FDTD method and that the S-FDTD method can be usefully employed for space increments in the order of \lambda/25 to \lambda/50.
Power Distortion Issues In Wind Turbine Power Systems Under Transient States, Tadeusz Lobos, Jacek Rezmer, Tomasz Sikorski, Zbigniew Waclawek
Power Distortion Issues In Wind Turbine Power Systems Under Transient States, Tadeusz Lobos, Jacek Rezmer, Tomasz Sikorski, Zbigniew Waclawek
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper time-frequency methods have been investigated for complex investigations of transient states in wind power plants. Application of parallel processing in time and frequency domain brought new findings in description of wind power plants working under transient conditions. Proposed algorithms represents standard Short-Time Fourier Transform (STFT) as well as alternative methods associated with Cohen's class: Choi-Williams Distribution (CWD) and Zhao-Atlas-Marks Distribution (ZAMD). In order to explore advantages and disadvantages of the method several experiments were performed using model of squirrel-cage induction machine connected directly to the grid. Investigated phenomena concerned power distortion caused by switching-on capacitor banks and …
Synthesis And Characterizations Of Some New 4h-1,2,4-Triazole Derivatives, Nesli̇han Demi̇rbaş, Ahmet Demi̇rbaş, Şule Ceylan, Deni̇z Şahi̇n
Synthesis And Characterizations Of Some New 4h-1,2,4-Triazole Derivatives, Nesli̇han Demi̇rbaş, Ahmet Demi̇rbaş, Şule Ceylan, Deni̇z Şahi̇n
Turkish Journal of Chemistry
3-[(5-Amino-1,3,4-thiadiazol-2-yl)methyl]-4-ethoxycarbonylamino-5-alkyl-4H-1,2,4-triazoles (2a,b) were obtained from the reaction of 3-cyanomethyl-5-alkyl-4-ethoxycarbonylamino-4H-1,2,4-triazoles (1a,b) with thiosemicarbazide in the presence of trifluoroacetic acid. The treatment of the obtained compounds (2a,b) with acetic anhydride for 1 h afforded 3-[(5-acetylamino-1,3,4-thiadiazol-2-yl)methyl]-4-ethoxycarbonylamino-5-alkyl-4H-1,2,4-triazoles (3a,b). The synthesis of 4-ethoxycarbonylamino-3-[(2,3-dihydro-1,3-benzoxazol-2-yl)methyl]-5-(4-methylbenzyl)-4H-1,2,4-triazole (4) was performed by the treatment of 3-[(5-acetylamino-1,3,4-thiadiazol-2-yl)methyl]-4-ethoxycarbonylamino-5-(4-methylbenzyl)-4H-1,2,4-triazole (3a) with o-aminophenol under nitrogen atmosphere for 50 h. The reaction of compounds 1a,b with salicylaldehyde in the presence of sodium ethoxide yielded 2-{4-[(ethoxycarbonyl)amino]-5-alkyl-4H-1,2,4-triazol-3-yl}-3-(2-hydroxyphenyl)-acrylonitriles (5a,b). The acetylations of compounds 5a,b with acetic anhydride for 5 h resulted in the formation of 2-{4-[acetyl(ethoxycarbonyl)amino]-5-alkyl-4H-1,2,4-triazol-3-yl}-3-[2-(acetyloxy)phenyl]-acrylic acids (6a,b). On the other hand, the treatment of compounds 5a,b with …
Synthesis Of New Azo Dyes And Copper(Ii) Complexes Derived From Barbituric Acid And 4-Aminobenzoylhydrazone, Bülent Kirkan, Ramazan Gup
Synthesis Of New Azo Dyes And Copper(Ii) Complexes Derived From Barbituric Acid And 4-Aminobenzoylhydrazone, Bülent Kirkan, Ramazan Gup
Turkish Journal of Chemistry
Four new azo dyes, L^1, L^2, L^3, and L^4, were prepared by linking benzaldehyde p-aminobenzoylhydrazone (3) and p-hydroxybenzaldehyede p--aminobenzoylhydrazone (4) to barbituric acid and 1,3-dimethylbarbituric acid through diazo-coupling reactions. Reactions of the azo-dyes with copper chloride and bidentate ligand, 1,10-phenanthroline, produced mixed-ligand dinuclear complexes with general stoichiometry [Cu_2L(phen)_2]Cl_2 (7, 8, 9, and 10). The structures of both azo dyes and their complexes were identified by elemental analyses, FT-IR, ^1H-NMR, UV-VIS, magnetic susceptibility, and mass spectral data.
One Step Synthesis Of Some 2,5,6-Trisubstituted-1,3-Dioxin-4-Ones, Ahmet Şener, İshak Bi̇ldi̇ri̇ci̇, Hasan Genç, Nuretti̇n Mengeş, Siddik Eski̇noba
One Step Synthesis Of Some 2,5,6-Trisubstituted-1,3-Dioxin-4-Ones, Ahmet Şener, İshak Bi̇ldi̇ri̇ci̇, Hasan Genç, Nuretti̇n Mengeş, Siddik Eski̇noba
Turkish Journal of Chemistry
A number of novel 2,5,6-trisubstituted-1,3-dioxin-4-one derivatives were synthesized via one step reactions between dibenzoylmethane or benzoylacetone and oxalyl chloride in refluxing solvents containing various aldehydes.
Synthesis, X-Ray Structure, And Bioassay Of Newly Synthesized Trimethyltin(Iv) 2,3-Methylenedioxy Benzoate, Mukhtiar Hussain, Muhammad Hanif, Saqib Ali, Saira Shahzadi, Helen S. Evans
Synthesis, X-Ray Structure, And Bioassay Of Newly Synthesized Trimethyltin(Iv) 2,3-Methylenedioxy Benzoate, Mukhtiar Hussain, Muhammad Hanif, Saqib Ali, Saira Shahzadi, Helen S. Evans
Turkish Journal of Chemistry
Trimethyltin(IV) complex containing the carboxylate ligand 2,3-methylenedioxybenzoic acid (HL) have been synthesized and characterized in solution state by multinuclear NMR (^1H, ^{13}C and ^{119}Sn) using the noncoordinating solvent and also in solid sate by FTIR, mass spectrometry, and X-ray crystallography. Spectroscopic data have shown that methylenedioxy moiety has not coordinated with tin atom; instead, the coordination site is a -COO group, which is proved by spectral and XRD data. The solid state structure shows the trigonal bipyramidal geometry with a space group P2_1/c. This compound was tested for its in vitro antitumor activity.
Investigation Of Solid State Synthesis And Characterizations Of Novel Sodium Rare-Earth Oxyphosphates, Semi̇h Seyyi̇doğlu, Maci̇t Özenbaş, Ayşen Yilmaz
Investigation Of Solid State Synthesis And Characterizations Of Novel Sodium Rare-Earth Oxyphosphates, Semi̇h Seyyi̇doğlu, Maci̇t Özenbaş, Ayşen Yilmaz
Turkish Journal of Chemistry
A new orthorhombic phase of Na_2LaOPO_4 (sodium lanthanum oxyphosphate), and novel Na_2NdOPO_4 (sodium neodymium oxyphosphate), Na_2SmOPO_4 (sodium samarium oxyphosphate) were synthesized by solid state reactions of Na_2CO_3, NH_4H_2PO_4, and Ln_2O_3 (Ln = La, Nd, and Sm). The unit cell dimensions were calculated using their X-ray powder diffraction data, which were a = 13.60(1), b = 12.71(1), and c = 6.96(1) Å, a = 13.466(5), b = 12.547(6), and c = 6.932(5) Å, and a = 13.54(1), b = 12.577(8), and c = 7.047(5) Å, respectively, and the probable space group was Pmm2. Using the same procedure orthorhombic Na_2DyOPO_4 (sodium dysprosium …