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Articles 8611 - 8640 of 10319
Full-Text Articles in Physical Sciences and Mathematics
The Born Scattering Amplitude Of A Non-Relativistic Spin One-Half Particle In An Aharonov-Bohm Potentia, Yousef Romia, Mohammad Shikakhwa
The Born Scattering Amplitude Of A Non-Relativistic Spin One-Half Particle In An Aharonov-Bohm Potentia, Yousef Romia, Mohammad Shikakhwa
Turkish Journal of Physics
The Born scattering amplitude of a non-relativistic spin one-half particle in an Aharonov-Bohm potential is calculated up to second order. It is demonstrated that perturbation theory works well for this model, in contrast with the case of scalar particles, thanks to the spin-magnetic moment interaction term. The first order amplitude is shown to coincide with the exact amplitude when expanded to the same order; the second order amplitude is finite and null. The polarized scattering cross section is found to be different from the unpolarized one only if the incident particle has a spin component perpendicular to the flux tube.
Amps-1d Modeling Of A-Si:H N^{+}-I-N^{+} Structure: The Validity Of Space Charge Limited Current Analysis, Aynur Eray, G. Nobile
Amps-1d Modeling Of A-Si:H N^{+}-I-N^{+} Structure: The Validity Of Space Charge Limited Current Analysis, Aynur Eray, G. Nobile
Turkish Journal of Physics
In this paper, the AMPS-1D (Analysis of Microelectronic and photonic structure) simulation program is used to understand the origin of the differences observed in Space Charge Limited Current (SCLC) analysis in thin and thick a-Si:H n^{ +} -i- n^{+} structure. For that purpose, the problem of applicability of SCLC measurements to n^{+}-i-n^{+} a-Si:H samples are investigated by using both the thin (0.3 \mu m) and thick (3 \mu m) samples. The simulation results show that activation energy in thick samples is larger than in thinner samples, which are an agreement with the experimental results. It is emphasized that this method …
An Algorithm To Recognise Small Seifert Fiber Spaces, J. Hyam Rubinstein
An Algorithm To Recognise Small Seifert Fiber Spaces, J. Hyam Rubinstein
Turkish Journal of Mathematics
The homeomorphism problem is, given two compact n-manifolds, is there an algorithm to decide if the manifolds are homeomorphic or not. The homeomorphism problem has been solved for many important classes of 3-manifolds - especially those with embedded 2-sided incompressible surfaces (cf [12], [15], [16]), which are called Haken manifolds. It is also well-known that the homeomorphism problem is easily solvable for two 3-manifolds which admit geometries in the sense of Thurston [36], [31]. Hence the recognition problem, to decide if a 3-manifold has a geometric structure, is a significant problem. The recognition problem has been solved for all geometric …
Radical Submodules And Uniform Dimension Of Modules, Patrick F. Smith
Radical Submodules And Uniform Dimension Of Modules, Patrick F. Smith
Turkish Journal of Mathematics
We investigate the relations between a radical submodule N of a module M being a finite intersection of prime submodules of M and the factor module M/N having finite uniform dimension. It is proved that if N is a radical submodule of a module M over a ring R such that M/N has finite uniform dimension, then N is a finite intersection of prime submodules. The converse is false in general but is true if the ring R is fully left bounded left Goldie and the module M is finitely generated. It is further proved that, in general, if a …
Fuzzy \Beta-Compactness And Fuzzy \Beta-Closed Spaces, I. M. Hanafy
Fuzzy \Beta-Compactness And Fuzzy \Beta-Closed Spaces, I. M. Hanafy
Turkish Journal of Mathematics
The concepts of \beta-compactness and \beta-closed spaces in the fuzzy setting are defined and investigated. Fuzzy filterbases are used to characterize these concepts. A comparison between these types and some different forms of compactness in fuzzy topology is established.
The Trace Formula For A Differential Operator Of Fourth Order With Bounded Operator Coefficients And Two Terms, Erdal Gül
Turkish Journal of Mathematics
L Yıldız Teknik Üniversitesi Fen-Edebiyat Fakültesi Matematik Bölümü Davutpaşa Kampüsü İstanbul-TURKEY e-mail: gul@yildiz.edu.tr We investigate the spectrum of a differential operator of fourth order with bounded operator coefficients and find a formula for the trace of this operator.
Splitting Of Sharply 2-Transitive Groups Of Characteristic 3, Seyfi̇ Türkelli̇
Splitting Of Sharply 2-Transitive Groups Of Characteristic 3, Seyfi̇ Türkelli̇
Turkish Journal of Mathematics
We give a group theoretic proof of the splitting of sharply 2-transitive groups of characteristic 3.
A New Characteristic Of Möbius Transformations By Use Of Apollonius Points Of Pentagons, Serap Bulut, Ni̇hal Yilmaz Özgür
A New Characteristic Of Möbius Transformations By Use Of Apollonius Points Of Pentagons, Serap Bulut, Ni̇hal Yilmaz Özgür
Turkish Journal of Mathematics
In this paper, we give a new characterization of Möbius transformations. To this end, a new concept of ''Apollonius points of pentagons'' is used.
Rate Of Convergence Of Durrmeyer Type Baskakov-Bezier Operators For Locally Bounded Functions, Vijay Gupta
Rate Of Convergence Of Durrmeyer Type Baskakov-Bezier Operators For Locally Bounded Functions, Vijay Gupta
Turkish Journal of Mathematics
In the present paper, we introduce the Durrmeyer variant of Baskakov-Bezier operators B_{n,\alpha} (f,x), which is the modified form of Baskakov-Beta operators. Here we obtain an estimate on the rate of convergence of B_{n,\alpha} (f,x) for functions of bounded variation in terms of Chanturiya's modulus of variation. In the end we also propose an open problem for the readers.
Thermochemical And Green Luminescence Analysis Of Zinc Oxide Thin Films Grown On Sapphire By Chemical Vapor Deposition, Abdelkader Djelloul, R. A. Rabadanov
Thermochemical And Green Luminescence Analysis Of Zinc Oxide Thin Films Grown On Sapphire By Chemical Vapor Deposition, Abdelkader Djelloul, R. A. Rabadanov
Turkish Journal of Physics
This study has been carried out to detail an integral thermochemical analysis of the principal reaction in the production of zinc oxide (ZnO) thin films, including developing an analytical form of the equilibrium constant. Zinc oxide thin films prepared by chemical vapor deposition have been studied in terms of deposition time and substrate temperature. The growth of the single-crystal films present two regimes depending on the substrate temperature, with increasing constant growth rates at lower, and higher, temperature ranges, respectively. Growth rates above 6 \mu m \cdot min^{-1} can be achieved at T_s = 880 K. The variation of the …
Single Mode Optical Radiation Distribution And Reflectivity Calculations In Novel-Hot Electron Light Emission And Lasing In Semiconductor Heterostructures Vcsels, Ebru Şenadim Tüzemen, Yüksel Ergun
Single Mode Optical Radiation Distribution And Reflectivity Calculations In Novel-Hot Electron Light Emission And Lasing In Semiconductor Heterostructures Vcsels, Ebru Şenadim Tüzemen, Yüksel Ergun
Turkish Journal of Physics
In this work, we calculate the power reflectivity in vertical cavity surface emitting lasers (VCSELs) using a new method. In VCSELs, the stop band of the reflectivity spectrum should exhibit a dip at the lasing wavelength, which is a condition for lasing. This current approximation method gives a simple analytical expression to find the power reflectivity as a function of wavelength in the vicinity of lasing wavelength, \lambda_°. The proposed method can generally be applied to semiconductor VCSEL systems for a given lasing wavelength.
Polar Optical Phonon Modes And Fröhlich Electron-Phonon Interaction Hamiltonians In Coaxial Cylindrical Quantum Cables, Li Zhang, Hong-Jing Xie
Polar Optical Phonon Modes And Fröhlich Electron-Phonon Interaction Hamiltonians In Coaxial Cylindrical Quantum Cables, Li Zhang, Hong-Jing Xie
Turkish Journal of Physics
By using the dielectric continuum approximation, the polar optical phonon modes of coaxial cylindrical quantum cables with arbitrary layer-number were studied. In order to describe the vibrating of the longitudinal-optical (LO) phonons, a set of legitimate eigenfunctions for LO phonon modes are constructed and adopted. In order to deal with the interface optical (IO) phonon modes, the transfer matrix method is employed. The quantized LO and IO phonons fields, as well as their corresponding Fröhlich electron-phonon interaction Hamiltonians, are also derived. Numerical calculations on a four-layer GaAs/Al_xGa_{1-x}As QC have been performed. Results reveal that there are six branches of IO …
Moments Equalities For Nonnegative Integer-Valued Random Variables, Mohamed I. Riffi
Moments Equalities For Nonnegative Integer-Valued Random Variables, Mohamed I. Riffi
Turkish Journal of Mathematics
We present and prove two theorems about equalities for the nth moment of nonnegative integer-valued random variables. These equalities generalize the well known equality for the first moment of a nonnegative integer-valued random variable X in terms of its cumulative distribution function, or in terms of its tail distribution.
On The Power Subgroups Of The Extended Modular Group \Gamma, Recep Şahi̇n, Sebahatti̇n İki̇kardeş, Özden Koruoğlu
On The Power Subgroups Of The Extended Modular Group \Gamma, Recep Şahi̇n, Sebahatti̇n İki̇kardeş, Özden Koruoğlu
Turkish Journal of Mathematics
In this paper we describe the group structure of power subgroups \Gamma^m of the extended modular group \Gamma and the quotients to them. Then we give some relations between the power subgroups \Gamma^m, the commutator subgroups \Gamma^{\prime} and \Gamma^{\prime \prime} and also the information of interest about free normal subgroups of the extended modular group \Gamma.
On Near-Rings With Two-Sided \Alpha-Derivations, Nurcan Argaç
On Near-Rings With Two-Sided \Alpha-Derivations, Nurcan Argaç
Turkish Journal of Mathematics
In this paper, we introduce the notion of two-sided \alpha-derivation of a near-ring and give some generalizations of [1]. Let N be a near ring. An additive mapping f: N\rightarrow N is called an { \it (\alpha, \beta)-derivation } if there exist functions \alpha,\beta : N\rightarrow N such that f(xy)=f(x)\alpha(y)+\beta (x)f(y) for all x,y\in N. An additive mapping d:N\rightarrow N is called a two-sided \alpha-derivation if d is an (\alpha,1)-derivation as well as a (1,\alpha)-derivation. The purpose of this paper is to prove the following two assertions: (i) Let N be a semiprime near-ring, I be a subset of N …
Coisotropic Submanifolds Of A Semi-Riemannian Manifold, Erol Kiliç, Bayram Şahi̇n, H. B. Karadağ, R. Güneş
Coisotropic Submanifolds Of A Semi-Riemannian Manifold, Erol Kiliç, Bayram Şahi̇n, H. B. Karadağ, R. Güneş
Turkish Journal of Mathematics
In this paper, we study coisotropic submanifolds of a semi-Riemannian manifold. We investigate the integrability condition of the screen distribution and give a necessary and sufficient condition on Ricci tensor of a coisotropic submanifold to be symmetric. Finally, we present some new theorems and results about totally umbilical coisotropic submanifolds of a semi-Riemannian manifold
On Simultaneous Approximation By A Linear Combination Of A New Sequence Of Linear Positive Operators, P. N. Agrawal, Ali J. Mohammad
On Simultaneous Approximation By A Linear Combination Of A New Sequence Of Linear Positive Operators, P. N. Agrawal, Ali J. Mohammad
Turkish Journal of Mathematics
In [1] we introduced a new sequence of linear positive operators M_{n} to approximate unbounded continuous functions of exponential growth on [0,\infty). As this sequence is saturated with O(n^{-1}), to accelerate the rate of convergence we applied the technique of linear combination introduced by May [3] and Rathore et al. [4] to these operators. The object of the present paper is to study the phenomena of simultaneous approximation (approximation of derivatives of functions by the corresponding order derivatives of operators) by the linear combination M_{n} ( . , k, x) of M_{n}. First, we establish a Voronovskaja-type asymptotic formula and …
F-Invariant Submanifolds Of Kaehlerian Product Manifold, Mehmet Atçeken
F-Invariant Submanifolds Of Kaehlerian Product Manifold, Mehmet Atçeken
Turkish Journal of Mathematics
In this paper, the geometry of F-invariant submanifolds of a Kaehlerian product manifold is studied. The fundamental properties of these submanifolds are investigated such as pseudo umbilical, curvature invariant, totally geodesic, mixed geodesic submanifold and locally decomposable Riemannian product manifold.
A Generalization Of A Result On Torsion-Free Groups With All Subgroups Subnormal, Tahi̇re Özen
A Generalization Of A Result On Torsion-Free Groups With All Subgroups Subnormal, Tahi̇re Özen
Turkish Journal of Mathematics
The main result in this paper is the following: Let G be a torsion-free locally nilpotent group and let F be a finitely generated subgroup of G. If every subgroup of G containing F is subnormal in G, then G is nilpotent.
On Local Hörmander-Beurling Spaces, Jairo Villegas
On Local Hörmander-Beurling Spaces, Jairo Villegas
Turkish Journal of Mathematics
In this paper we aim to extend a result of Hörmander's, that \mathcal{B}_{p,k}^{loc}(\Omega)\subset\mathcal{C}^m(\Omega) if \frac{(1+\left \cdot\right )^m}{k}\in L_{p^\prime}, to the setting of vector valued local Hörmander-Beurling spaces, as well as to show that the space \bigcap_{j=1}^\infty\mathcal{B}_{p_j,k_j}^{loc} (\Omega, E) (1\leq p_j\leq\infty, k_j=e^{j\omega}, j=1,2,\dots) is topologically isomorphic to \mathcal{E}_\omega(\Omega, E ). Moreover, it is well known that the union of Sobolev spaces \mathcal{H}_{s}^{loc}(\Omega) (=\mathcal{B}_{2,(1+ \cdot ^2)^{s/2}}^{loc}(\Omega)) coincides with the space \mathcal{D}^{\prime\,F}(\Omega) of finite order distributions on \Omega. We show that this is also verified in the context of vector valued Beurling ultradistributions.
A Note On Groups With All Subgroups Subnormal, Ahmet Arikan, Tahi̇re Özen
A Note On Groups With All Subgroups Subnormal, Ahmet Arikan, Tahi̇re Özen
Turkish Journal of Mathematics
We prove that if G is a periodic group with all subgroups subnormal, and if for every x, y \in G, ^{G} is an FC-group, then G is nilpotent.
Mining Classification Rules By Using Genetic Algorithms With Non-Random Initial Population And Uniform Operator, Korkut Koray Gündoğan, Bi̇lal Alataş, Ali̇ Karci
Mining Classification Rules By Using Genetic Algorithms With Non-Random Initial Population And Uniform Operator, Korkut Koray Gündoğan, Bi̇lal Alataş, Ali̇ Karci
Turkish Journal of Electrical Engineering and Computer Sciences
Classification is a supervised learning method that induces a classification model from a database and is one of the most commonly applied data mining task. The frequently employed techniques are decision tree or neural network-based classification algorithms. This work presents an efficient genetic algorithm (GA) for classification rule mining technique that discovers comprehensible IF-THEN rules using a generalized uniform population method and a uniform operator inspired from the uniform population method. Initial population is generated by methodically eliminating the randomness by generalized uniform population method. In the subsequence generations, genetic diversity is ensured and premature convergence is prevented by the …
A Platform For Software Engineering Course Projects, Bi̇rol Aygün
A Platform For Software Engineering Course Projects, Bi̇rol Aygün
Turkish Journal of Electrical Engineering and Computer Sciences
The importance of projects in software engineering courses is well known. Both synthetic and real-life projects have various advantages and disadvantages. Our aim was to create a framework where students can develop projects which reflect some of the complexities of real-life, involving many concurrent, interacting, asynchronous processes, each in a different stage of development, with wide temporal differences among them - some occurring within millisconds of each other and others executing sporadically over much longer periods. In this project, which was carried out in different arrangements in several software engineering courses in three universities, the students developed both the sub- …
Synthesis And Reactivity Of Tetrahydroimidazo [1,5-B][1,2,4]Oxadiazol- 2(1h)-Thiones, Necdet Coşkun, Fatma Ti̇rli̇ Tat
Synthesis And Reactivity Of Tetrahydroimidazo [1,5-B][1,2,4]Oxadiazol- 2(1h)-Thiones, Necdet Coşkun, Fatma Ti̇rli̇ Tat
Turkish Journal of Chemistry
1,3-Dipolar cycloaddition of imidazoline 3-oxides 1 with methylisothiocyanate proceeds regio- and diastereoselectively to give tetrahydroimidazo[1,5-b][1,2,4]oxadiazol-2(1H)-thiones 3 in high yields. The cis configuration of the adducts was proved by our double cis elimination test as well as by NOESY experiments. Adducts 3a-c undergo ring opening at reflux in acetonitrile to give imidazoles while 3d-e undergo retro dipolar cycloaddition to give the starting nitrones 1d-e. The imidazooxadiazol-2-thiones 3a-e were treated with concentrated HCl in ethanol at 50 °C to give the corresponding 4H-[1,2,4]oxadiazole-5-thione only in cases in which the substituent at C-6 is an aryl.
Kinetics And Mechanism Of Oxidation Of N--Propanolamine By Dihydroxydiperiodatonickelate(Iv) In Alkaline Medium, Jin-Huan Shan, Jing Qian, Ming-Zhu Gao, Shi-Gang Shen, Han-Wen Sun
Kinetics And Mechanism Of Oxidation Of N--Propanolamine By Dihydroxydiperiodatonickelate(Iv) In Alkaline Medium, Jin-Huan Shan, Jing Qian, Ming-Zhu Gao, Shi-Gang Shen, Han-Wen Sun
Turkish Journal of Chemistry
The kinetics of oxidation of n--Propanolamine (n-PA) by dihydroxy diperiodato-nickelate(IV) (DPN) in alkaline medium was studied with spectrophotometry in a temperature range of 293.2-308.2 K. The reaction was found to be pseudo first-order with respect to DPN and fractional order to n-PA. The rate conatant k_{obs}, rose with an increase in the concentration of OH^{-} and a decrease in the concentration of IO_{4}^{-}. Added salts did not affect the rate and no free radical was detected. From the evaluation of linear data, a reaction mechanism is proposed which involves a pre-equilibrium of an adduct formation between n-PA and dihydroxymonoperiodatonickelate(IV) (MPN), …
Synthesis, Spectral Characterization And Biological Applications Of Tri- And Diorganotin(Iv) Derivatives Of 2-[N-(2,6-Dichloro-3-Methylphenyl)Amino]Benzoic Acid, Sohail Mahmood, Saqib Ali, Moazzam Hussain Bhatti, Mohammad Mazhar, Khadija Shahid, Khalid Mohammed Khan, Ghulam Mustafa Maharvi
Synthesis, Spectral Characterization And Biological Applications Of Tri- And Diorganotin(Iv) Derivatives Of 2-[N-(2,6-Dichloro-3-Methylphenyl)Amino]Benzoic Acid, Sohail Mahmood, Saqib Ali, Moazzam Hussain Bhatti, Mohammad Mazhar, Khadija Shahid, Khalid Mohammed Khan, Ghulam Mustafa Maharvi
Turkish Journal of Chemistry
A series of tri- and diorganotin(IV) compounds with the general formulae R_{3}SnL and R_{2}SnL_{2} (where R = Me, n-Bu, Ph and L = 2-[N-(2,6-dichloro-3-methylphenyl)-amino]benzoate) were synthesized. These compounds were characterized by different instrumental methods such as infrared, multinuclear NMR (^{1}H, ^{13}C, ^{119}Sn) and mass spectrometry. The spectroscopic investigation illustrates that the carboxylate group acts as a bidentate in solid state and as a monodentate in solution. Biological screening tests reveal that the investigated compounds have potential as antibacterial agents.
New Adsorbents From Ti(Opr^{N})_{4} By The Sol-Gel Process: Synthesis, Characterization And Application For Removing Some Heavy Metal Ions From Aqueous Solution, Funda Sayilkan, Hi̇kmet Sayilkan, Sema Erdemoğlu, Şadi̇ye Şener, Murat Akarsu
New Adsorbents From Ti(Opr^{N})_{4} By The Sol-Gel Process: Synthesis, Characterization And Application For Removing Some Heavy Metal Ions From Aqueous Solution, Funda Sayilkan, Hi̇kmet Sayilkan, Sema Erdemoğlu, Şadi̇ye Şener, Murat Akarsu
Turkish Journal of Chemistry
New adsorbents were synthesized by the sol-gel process from the product of a hydrolysis reaction and its coated form of titanium(IV)-n-propoxide for removing some heavy metal ions from aqueous solution. Titanium(IV)-n-propoxide was uncatalyst hydrolyzed with different amounts of water at room temperature and was found to react in a 1:1.6 ratio (mole of Ti:mole of H_{2}O). It was found that the condensation following the hydrolysis reaction was alcohol condensation. The hydrolysis-condensation product was characterized in detail by GC, Karl-Fischer coulometric titrator, NIR-spectroscopy, FT-IR spectroscopy, TG-DTA and elemental analysis. The hydrolysis-condensation product of titanium(IV)-n-propoxide was calcinated at 900 °C after drying …
One Step Synthesis And Some Reactions Of 7-Hydrazino-3,4-Diphenyl- 2h-Pyrazolo [3,4-D] Pyridazine, Ahmet Şener
One Step Synthesis And Some Reactions Of 7-Hydrazino-3,4-Diphenyl- 2h-Pyrazolo [3,4-D] Pyridazine, Ahmet Şener
Turkish Journal of Chemistry
The 7-hydrazino-3,4-diphenyl-2H-pyrazolo-[3,4-d]-pyridazine 3, obtained in 2 different ways consisting of the reactions of anhydrous hydrazine with 4-benzoyl-5-phenyl-2,3-dihydro-2,3-furandione 1 or 3,4-diphenyl-2H-pyrazolo-[3,4-d]-pyridazin-7(6H)-one 2, was converted into hydrazone derivatives 4 by the reactions of 3 with various salicylaldehydes.
Ftir And Ft-Raman Spectral Investigations On 4-Aminoquinaldine And 5-Aminoquinoline, N. Puviarasan, V. Arjunan, S. Mohan
Ftir And Ft-Raman Spectral Investigations On 4-Aminoquinaldine And 5-Aminoquinoline, N. Puviarasan, V. Arjunan, S. Mohan
Turkish Journal of Chemistry
The FTIR spectra of 4-aminoquinaldine and 5-aminoquinoline were recorded in solid phase on a Bruker IFS 66V spectrometer in the region 4000--400 cm^{-1}. The FT-Raman spectra of these compounds were also recorded in the same instrument with a FRA 106 Raman module. The molecules under investigation are considered to have a C_{S} point group by assuming the --NH_{2} and --CH_{3} groups as point masses. All the vibrations are both IR and Raman active. The simple general valance force field (SGVFF) is adopted for both inplane and out of plane vibrations. All the frequencies are assigned in terms of fundamentals, overtones …
Determination Of ^{90}Sr Accumulation In Human Teeth, Recep Acar, Orhan Acar
Determination Of ^{90}Sr Accumulation In Human Teeth, Recep Acar, Orhan Acar
Turkish Journal of Chemistry
The accumulation of ^{90}Sr in decayed or exfoliated human teeth was investigated by ultra low level beta counting. Fuming nitric acid and the necessary carriers and reagents were used for dissolving the samples, and the separation and purification of ^{90}Sr. The Ca contents of samples were determined by flame atomic absorption spectrometry with Zeeman-effect background correction. A mixture of K and La used as a matrix modifier was found to be preferable for the determination of Ca in samples. The optimum concentration and concentration ratio of K and La on the absorbance of Ca in the NIST certified reference material, …