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The Energy Spectra Of Gaas/Al_Xga_{1-X}As Quantum Dots, Mohammad El-Said, M. Abu Saa Jan 1998

The Energy Spectra Of Gaas/Al_Xga_{1-X}As Quantum Dots, Mohammad El-Said, M. Abu Saa

Turkish Journal of Physics

The energy expressions for QD presented in high- and low-magnetic fields are calculated. An interpolation formula between the energies of the quantum dot in both limits is proposed. The formula is implemented to produce the energy spectra of the parabolic quantum dot in the presence of a magnetic field of arbitrary strength. The transitions in the angular momenta of the ground state energy of interacting electrons confined in the quantum dot as a function of magnetic field strength is studied. A good agreement is obtained when our results are tested against exact numerical work.


A Time-Dependent Quantum Study Of Li+Hf(\Nu=1) -> Lif(\Nu')+H, Fahrettin Gögtaş, Gabriel G. Balint-Kurti Jan 1998

A Time-Dependent Quantum Study Of Li+Hf(\Nu=1) -> Lif(\Nu')+H, Fahrettin Gögtaş, Gabriel G. Balint-Kurti

Turkish Journal of Physics

Time-dependent quantum wave packet calculations are performed for a model based (two-dimensional) $Li+HF(\nu=1)\ra LiF(\nu^{\prime})+H$ reaction. The reaction probabilities for a broad range of collison energies are calculated by a single solution of the time-dependent Schr\\"{o}dinger equation. The calculated reaction probabilities show many sharp features as a function of energy which are ascribed to scattering resonances.


Cover And Contents Jan 1998

Cover And Contents

Turkish Journal of Zoology

No abstract provided.


Adaptive Shape From Shading, Ati̇lla Gülteki̇n, Muhi̇tti̇n Gökmen Jan 1998

Adaptive Shape From Shading, Ati̇lla Gülteki̇n, Muhi̇tti̇n Gökmen

Turkish Journal of Electrical Engineering and Computer Sciences

Extracting surface orientation and surface depth from one or more images is one of the classic problems in computer vision. Shape-from-shading (SFS) deals with the recovery of 3-D shape from a single shaded image. The shape is recovered by minimizing an energy functional involving constraints such as smoothness. In this constrained problem, although the smoothness constraint helps to stabilize the minimization process, it pushes the reconstruction toward a smooth surface. In this paper, we present a new adaptive shape-from-shading method which reduces this oversmoothing by controlling the smoothness spatially over the image space. In order to improve the quality of …


A Parallel Pipelined Computer Architecture For Digital Signal Processing, Haluk Gümüşkaya, Bülent Örenci̇k Jan 1998

A Parallel Pipelined Computer Architecture For Digital Signal Processing, Haluk Gümüşkaya, Bülent Örenci̇k

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a parallel pipelined computer architecture and its six network configurations targeted for the implementation of a wide range of digital signal processing (DSP) algorithms described by both atomic and large grain data flow graphs. The proposed architecture is considered together with programmability, yielding a system solution that combines extensive concurrency with simple programming. It is an SSIMD (Skewed Single Instruction Multiple Data) or MIMD (Multiple Instruction Multiple Data) machine depending on the algorithms implemented and the programming methodologies. The concurrency that can be exploited by the algorithms using this Parallel pipelined architecture is both temporal and spatial …


Hierarchical Interconnection Network Architecture For Real-Time Systems, Bülent Örenci̇k Jan 1998

Hierarchical Interconnection Network Architecture For Real-Time Systems, Bülent Örenci̇k

Turkish Journal of Electrical Engineering and Computer Sciences

A hierarchical network suitable for interconnection of real-time client processes in a distributed multiprocessor environment is presented in this paper. A multi-layer {\it Communication Unit} (CU) prototype is developed for this purpose. This unit offers the client processes communication services for real-time operation. These services are structured in such a way that they do not depend on the characteristics of the communication medium. The basic hardware of the CU consists of a PC compatible card connected to the VME Bus. Client processes run on target cards (Motorola MVME-162) which are attached to the same bus. Target cards together with a …


Imaging Tissue Conductivity Via Contactless Measurements: A Feasibility Study, Nevzat G. Gençer, M. Nejat Tek Jan 1998

Imaging Tissue Conductivity Via Contactless Measurements: A Feasibility Study, Nevzat G. Gençer, M. Nejat Tek

Turkish Journal of Electrical Engineering and Computer Sciences

The feasibility of a new imaging system is investigated. This system will be used to image electrical conductivity distribution of biological tissues via contactless measurements. This will be achieved by introducing currents in the conductive medium using time-varying magnetic fields and measuring the magnetic fields of the induced currents. Consequently, the imaging system consists of transmitter and receiver coils placed nearby the conductive body. In this study, the basic features of the coplanar and coaxial coils are studied. The validity of the simplifying assumptions for the governing field equations is investigated. It is found that, for operating frequency of 100 …


On The Differential Prime Radical Of A Differential Ring, Djavvat Khadjiev, Fethi̇ Çallialp Jan 1998

On The Differential Prime Radical Of A Differential Ring, Djavvat Khadjiev, Fethi̇ Çallialp

Turkish Journal of Mathematics

In this paper we have obtained the following results for a differential ring (associative or nonassociative): (1) For a differential ring ({\cal D}-ring) we introduce definitions of a {\cal D}-prime {\cal D}-ideal, {\cal D}-semiprime {\cal D}-ideal and a strongly {\cal D}-nilpotent element. We define the {\cal D}-prime radical as the intersection of all {\cal D}-prime {\cal D}-ideals. For any {\cal D}-ring the {\cal D}-prime radical, the intersection of all {\cal D}-semiprime {\cal D}-semiprime {\cal D}-ideals and the set of all strongly {\cal D}-nilpotent elements are equal. (2) For a {\cal D}-ring we introduce a definition of an s-nilpotent {\cal D}-ideal. …


Normal Subgroups Of Hecke Groups On Sphere And, İsmai̇l Naci̇ Cangül, Osman Bi̇zi̇m Jan 1998

Normal Subgroups Of Hecke Groups On Sphere And, İsmai̇l Naci̇ Cangül, Osman Bi̇zi̇m

Turkish Journal of Mathematics

We use regular map theory to obtain all normal subgroups of Hecke groups of genus 0 and 1. The existence of a regular map corresponding uniquely to every normal subgroup of Hecke groups H(\lambda_q) is a result of Jones and Singerman, and it is frequently used here to obtain normal subgroups. It is found that when q is even, H(\lambda_q) has infinitely many normal subgroups on the sphere, while for odd q, this number is finite. The total number of normal subgroups of H(\lambda_q) on a torus is found to be either 0 or infinite. The latter case appears iff …


Fuzzy Ideals In Gamma Near-Rings, Young Bae Jun, Mehmet Sapanci, Mehmet Ali̇ Öztürk Jan 1998

Fuzzy Ideals In Gamma Near-Rings, Young Bae Jun, Mehmet Sapanci, Mehmet Ali̇ Öztürk

Turkish Journal of Mathematics

The aim of this paper is to introduce the notion of fuzzy left (resp. right) ideals of \Gamma-near-rings, and to study the related properties.


A Berry-Esseen Bound For Empty Boxes Statistic On The Scheme An Allocations Of Several Type Balls, S.A. Mirakhmedov, O. Saidova Jan 1998

A Berry-Esseen Bound For Empty Boxes Statistic On The Scheme An Allocations Of Several Type Balls, S.A. Mirakhmedov, O. Saidova

Turkish Journal of Mathematics

A Berry-Esseen bound for the number of empty cells in the scheme of independent and random allocation of balls of $s$ type into different cells is obtained.


Finite Direct Sums Of (D1)-Modules, Derya Keskin Jan 1998

Finite Direct Sums Of (D1)-Modules, Derya Keskin

Turkish Journal of Mathematics

In this paper we give necessary conditions for a finite direct sum of (D1)--modules to be a (D1)--module.


On Derived Equivalences And Local Structure Of Blocks Of Finite Groups, Markus Linckelmann Jan 1998

On Derived Equivalences And Local Structure Of Blocks Of Finite Groups, Markus Linckelmann

Turkish Journal of Mathematics

No abstract provided.


Crossed N-Cubes And N-Crossed Complexes Of Commutative Algebras, Z. Arvasi̇, M. Koçak Jan 1998

Crossed N-Cubes And N-Crossed Complexes Of Commutative Algebras, Z. Arvasi̇, M. Koçak

Turkish Journal of Mathematics

In this paper we will define crossed $\Bbb N$-cubes and n-crossed complexes of commutative algebras and construct a functor from the category of simplicial algebras to that of n-crossed complexes.


Pullbacks Of Crossed Modules And Cat^1-Groups, Murat Alp Jan 1998

Pullbacks Of Crossed Modules And Cat^1-Groups, Murat Alp

Turkish Journal of Mathematics

In this paper, wer define the pullback cat$^{1}$-groups and we showed that the category of bullback cat$^{1}$-group is equivalent to the category of pullback crossed modules. 1991 A. M. S. C.: 13D99, 16A99, 17B99, 18D35.


Derivation Of Separable Amplitude Equations By Multiple Scales Method, Mehmet Naci̇ Özer, Dursun Eser Jan 1998

Derivation Of Separable Amplitude Equations By Multiple Scales Method, Mehmet Naci̇ Özer, Dursun Eser

Turkish Journal of Mathematics

The method of multiple scales is used to derive separable nonlinear Schrödinger equations as amplitude equation from three component 2D nonlinear Klein-Gordon Equation. We further discuss the integrability of the derived separable amplitude equations and reduce them into finite dimensional Hamiltonian systems. Finally we give first integrals for the reduced systems.


The Dual Of The Bochner Space L^P(\Mu,E) For Arbitrary \Mu, Bahatti̇n Cengi̇z Jan 1998

The Dual Of The Bochner Space L^P(\Mu,E) For Arbitrary \Mu, Bahatti̇n Cengi̇z

Turkish Journal of Mathematics

Let $\mu$ be a finite measure, $E$ a Banach space, and $1\leq p


Direct Sums And The Schur Property, Betül Tanbay Jan 1998

Direct Sums And The Schur Property, Betül Tanbay

Turkish Journal of Mathematics

It is a known fact that $\ell^1$, the dual space of the null sequences $c_0$, has the Schur property, that is, weakly convergent sequences in $\ell^1$ are norm convergent. In this paper, we prove that if $(X_{\alpha})_{\alpha\in I}$ are Banach spaces and $X=(\oplus_{\alpha\in I}X_{\alpha})_1$ their $l_1$-sum, then the space $X$ has the Schur property iff each factor $X_{\alpha}$ has it.


Cover And Contents Jan 1998

Cover And Contents

Turkish Journal of Veterinary & Animal Sciences

No abstract provided.


Cover And Contents Jan 1998

Cover And Contents

Turkish Journal of Veterinary & Animal Sciences

No abstract provided.


Cover And Contents Jan 1998

Cover And Contents

Turkish Journal of Veterinary & Animal Sciences

No abstract provided.


Cover And Contents Jan 1998

Cover And Contents

Turkish Journal of Veterinary & Animal Sciences

No abstract provided.


Cover And Contents Jan 1998

Cover And Contents

Turkish Journal of Veterinary & Animal Sciences

No abstract provided.


Electron Spectroscopy For Material Characterization, Ş. Süzer Jan 1998

Electron Spectroscopy For Material Characterization, Ş. Süzer

Turkish Journal of Chemistry

Basic principles of the two electron spectroscopic techniques, the x-ray photoelectron spectroscopy, XPS, and the Auger electron spectroscopy, AES, are given. Their utilization in material characterization are introduced through examples with application of these techniques to various surface related problems.


Solvent Extraction Of La^{3+} Withethylenediamine-N,N'-Ditetradecyl-N,N'-Diacetic Acid(Eddat) In Dichloromethane, Mürüvvet Yurdakoç, Halil Hoşgören Jan 1998

Solvent Extraction Of La^{3+} Withethylenediamine-N,N'-Ditetradecyl-N,N'-Diacetic Acid(Eddat) In Dichloromethane, Mürüvvet Yurdakoç, Halil Hoşgören

Turkish Journal of Chemistry

Ethylenediamine-N,N'-ditetradecyl-N,N'-diacetic acid (EDDAT) was synthesized for the solvent extraction of La$^{3+}$. EDDAT was prepared from ethylenediamine-N,N'-diacetic acid (EDDA) and tetradecyl bromide in a basic n-amylalcohol-ethanol-water solvent system. The structure of this new extracting reagent was identified according to spectroscopic data, i.e. $^{13}$C NMR, $^1$H NMR, and elemental analysis results. The solvent extraction of La$^{3+}$ with EDDAT in dichloromethane was studied as a function of parameters of the aqueous and organic phases. The optimal extraction conditions were determined. The extraction yield increased with a decrease in hydrogen ions in the aqueous phase. Stripping of the La$^{3+}$ loaded organic phase was achieved …


Comparison Of Different Production Processes For Bioethanol, B. Çaylak, Fazilet Vardar Sukan Jan 1998

Comparison Of Different Production Processes For Bioethanol, B. Çaylak, Fazilet Vardar Sukan

Turkish Journal of Chemistry

In this study, ethanol was produced with the microorganism {\em Saccharomyces cerevisiae} by using sucrose as a substrate. Batch processes were tested by using the same substrate, microorganism and medium composition. {\em Saccharomyces cerevisiae}, used in the free form in the first group of experiments, was immobilized by different methods. In the second group of experiments agar, sponge and a natural material called luffa cylindrica fiber were used as support materials. The batch processes with free and immobilized microorganisms were compared with respect to efficiency and yield.


Kinetic Studies Of The Thermal Decomposition Of Di- And Tri-Organotin Derivatives Of 1-Nitroso-2-Naphthol, Saqib Ali, Moazzam H. Bhatti, Sohail Mahmood, Muhammad Mazhar, M. Saleem Khalid, Nazar Hussain Jan 1998

Kinetic Studies Of The Thermal Decomposition Of Di- And Tri-Organotin Derivatives Of 1-Nitroso-2-Naphthol, Saqib Ali, Moazzam H. Bhatti, Sohail Mahmood, Muhammad Mazhar, M. Saleem Khalid, Nazar Hussain

Turkish Journal of Chemistry

The di- and tri-organotin complexes of general formula R$_2$SnL$_2$ and R$_3$SnL where R = C$_4$H$_9$, C$_6$H$_5$, C$_6$H$_5$CH$_2$, C$_6$H$_{11}$ and L=1-nitroso-2-naphthol, were subjected to thermal decomposition by means of thermogravimetry (TG). The decomposition occurred in steps and the kinetics of every set of reactions were determined using the method described by Coats and Redfern. These results were analysed to establish the decomposition kinetics and hence to calculate activation energies. The activation energies were also determined by applying the method described by Horowitz, which yielded comparable results.


Poly(3-Alkylthiophene) Modifications, A. Bolognesi Jan 1998

Poly(3-Alkylthiophene) Modifications, A. Bolognesi

Turkish Journal of Chemistry

No abstract provided.


The Amido And Bisalkoxo-Complexes Of [Tri(3,5-Dimethylpyrazolyl)Borato]Molydenum Nitrosyl, Işıl Topaloğlu Jan 1998

The Amido And Bisalkoxo-Complexes Of [Tri(3,5-Dimethylpyrazolyl)Borato]Molydenum Nitrosyl, Işıl Topaloğlu

Turkish Journal of Chemistry

In this study, the amido nitrosyl molybdenum complex, [Mo{HM(3,5-Me_2C_3HN_2)_3}(NO)Cl(NH_2)], was prepared. This compound reacts with alocohols, yielding the bisalkoxo complexes, [Mo{HM (3,5-Me_2C_3HN_2)_3}(NO)(OR)_{2}] (R = Me, Et, Pr^n, Bu^n). The new complexes were analyzed by IR and ^1H-NMR spectroscopy.


Recovery Of Copper, Cobalt, Nickel, Cadmium, Zinc And Bismuth From Electrolytic Copper Solution, Fırat Aydin, Ömer Yavuz, Berrin Zi̇yadanoğullari, Recep Zi̇yadanoğullari Jan 1998

Recovery Of Copper, Cobalt, Nickel, Cadmium, Zinc And Bismuth From Electrolytic Copper Solution, Fırat Aydin, Ömer Yavuz, Berrin Zi̇yadanoğullari, Recep Zi̇yadanoğullari

Turkish Journal of Chemistry

An electrolytic Copper Solution (ECS) was electrolyzed using platinum electrodes. Copper was obtained in solid form. In order to precipitate Cd(II), Bi(III), As(III), Sb(III) and the rest of the Cu(II) ions, H_2S gas was passed through the remaining solution. The remaining solution was evaporated to obtain metal sulphates. The sample containing metal sulphates was roasted at temperatures between 550 and 800°C. Cobalt, nickel and zinc in the solid sample remained in the form of metal sulphates, while the iron in the sample was converted into Fe_2O_3. This solid sample was dissolved in water and filtered in order to crystallize the …