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From Simplicial Groups To Crossed Complexes, Z. Arvasi̇ Jan 1998

From Simplicial Groups To Crossed Complexes, Z. Arvasi̇

Turkish Journal of Mathematics

In this paper, we will give a short proof of the construction of the crossed complex of groups by using the higher order Peiffer elements.


On The Validity Of The Borel-Hirzebruch Formula For Topological Actions, D. Dönmez Jan 1998

On The Validity Of The Borel-Hirzebruch Formula For Topological Actions, D. Dönmez

Turkish Journal of Mathematics

We defined an equivalence among group actions and find sufficient conditions for actions of compact connected Lie groups on Euclidean spaces for which the topological version of the Borel-Hirzebruch formula holds.


On The Parabolic Class Number Of Some Subgroups Of Hecke Groups, R. Keski̇n Jan 1998

On The Parabolic Class Number Of Some Subgroups Of Hecke Groups, R. Keski̇n

Turkish Journal of Mathematics

In this paper we calculate the parabolic class number of subgroups of Hecke groups ( H(\sqrt{2}), H (\sqrt{3}) ).


Locally Volume-Minimizing Codimension-One Foliation Of The Solid Torus, İ. Kocayusufoğlu, D. L. Jhonson Jan 1998

Locally Volume-Minimizing Codimension-One Foliation Of The Solid Torus, İ. Kocayusufoğlu, D. L. Jhonson

Turkish Journal of Mathematics

The aim of this paper is to construct a specific codimension-1 foliation of \( D^2 \times S^1 \) with one Reeb component, and to show that this foliation locally minimizes the volume among foliations with the boundary torus as a leaf.


Codes On Superelliptic Curves, F. Özbudak, M. Glukhov Jan 1998

Codes On Superelliptic Curves, F. Özbudak, M. Glukhov

Turkish Journal of Mathematics

The purpose of this paper is to apply superelliptic curves with a lot of rational points to construct rather good geometric Goppa codes.


Cover And Contents Jan 1998

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Turkish Journal of Mathematics

No abstract provided.


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Turkish Journal of Zoology

No abstract provided.


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Turkish Journal of Zoology

No abstract provided.


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Turkish Journal of Zoology

No abstract provided.


Elastic Scattering Of 344.5 Mev ^{12}C Ions From ^{11}B Nucleus, S.A.E. Khallaf, M.A. Abdel-Rahman, S.K. Abdel-Rahman, S.W.Z. Mahmoud Jan 1998

Elastic Scattering Of 344.5 Mev ^{12}C Ions From ^{11}B Nucleus, S.A.E. Khallaf, M.A. Abdel-Rahman, S.K. Abdel-Rahman, S.W.Z. Mahmoud

Turkish Journal of Physics

The angular distribution of the elastic scattering differential cross section of 344.5 MeV $^{12}$C ions from $^{11}$B nucleus is calculated and compared with the experimental data as well as the previously published calculations. The real part of the central optical potential is derived using the double-folding and single-folding procedures assuming Gaussian forms of the nucleon-nucleon and alpha-nucleon interactions, respectively. A nuclear matter density distribution function of $^{11}$B consisting of a spherical part plus a quadrupole term is used. The inclusion of the quadrupole term is found necessary to obtain good fits to the experimental data.


Electro-Optic Response Of A Polymer Dispersed Liquid Crystal Film, Rıdvan Karapinar Jan 1998

Electro-Optic Response Of A Polymer Dispersed Liquid Crystal Film, Rıdvan Karapinar

Turkish Journal of Physics

Polymer dispersed liquid crystal (PDLC) films are potentially useful in electro-optic devices since they can be used for vision products. In this work the PDLC thin films were prepared by a photopolymerization induced phase separation method and electro-optic properties of the films were investigated.


The Influence Of The Dispersion Of Boron Silicate On The Migration Of Non-Equilibrium Charge Carriers Generated By Eect Of An Electric Discharge, A.M. Hasanov Jan 1998

The Influence Of The Dispersion Of Boron Silicate On The Migration Of Non-Equilibrium Charge Carriers Generated By Eect Of An Electric Discharge, A.M. Hasanov

Turkish Journal of Physics

ESR was used in an investigation of the influence of Boron Silicate dispersion on the accumulation of paramagnetic centers (PC). It was observed that the rate of accumulation of PC increase by increasing of the grain size (r). At $r < 0.08$ mm the electrons ($F^+$-centers) are localized on the surface and with increasing grain size up to $0.08 < r < 0.22$ mm charge stratification takes place, the electrons are distributed in near-surface layer and the holes ($V$-centers) are localized in the bulk of the insulator. It was established that the transport of non-equilibrium charge carriers (NCC) from the bulk to the surface of Boron Silicate was due to a drift from the depth $(d \sim 10 \mu m)$ to a bulk-charge field generated by an electric discharge. The value of the surface field $E_s \sim 10^5 V/cm$ is determined by experimental results of the data. The kinetics of the isothermal annealing (300 K) are used to establish the influence of the surface field on the annihilation of NCC in the ''dead'' layer of separated charges.


Reorientation Of Magnetization In Thin Films, Bengü Kaplan Jan 1998

Reorientation Of Magnetization In Thin Films, Bengü Kaplan

Turkish Journal of Physics

The spin wave energy is determined by the competition between uniaxial and cubic anisotropy. We discuss the reorientation temperature $ T_{R} $ of magnetization in two-dimension and calculate its dependence on the exchange, $J$, and the uniaxial anisotropy, $G$, parameters within random phase approximation. We find that $ T_{R} $ varies as $ \sqrt{JG} $ in the planar regime.


Cover And Contents Jan 1998

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Turkish Journal of Physics

No abstract provided.


Dynamical System Topology Preserved In The Presence Of Noise, Judy A. Kennedy, James A. Yorke Jan 1998

Dynamical System Topology Preserved In The Presence Of Noise, Judy A. Kennedy, James A. Yorke

Turkish Journal of Mathematics

We first give a precise definition of the terms ``topological horseshoe'' and ``generalized quadrilateral'' and then examine the behavior of a homeomorphism F on a locally compact, separable, locally connected metric space X (X is usually a manifold in applications) such that F restricted to some generalized quadrilateral Q in X is a topological horseshoe map. For a set Q \subset X we define and describe (1) the permanent set Z of Q to be \{x\in X:F^n(x)\in Q for all integers n\}, and (2) the entrainment set of Q to be E(Q)=\{x\in X: F^{-n} (x)\in Q for all sufficiently large …


On The Cohomology Ring Of The Infinite Flag Manifold Lg/D, Cenap Özel Jan 1998

On The Cohomology Ring Of The Infinite Flag Manifold Lg/D, Cenap Özel

Turkish Journal of Mathematics

In this work, we discuss the calculation of cohomology rings of LG / T. First we describe the root system and Weyl group of LG, then we give some homotopy equivalences on the loop groups and homogeneous spaces, and investigate the cohomology ring structures of LSU_2 /T and \Omega SU_2. Also we prove that BGG-type operators correspond to partial derivation operators on the divided power algebras.


On 3 Dimensional Isotropic Submaniolds Of A Space From, Takehiro Itoh, Koichi Ogiue Jan 1998

On 3 Dimensional Isotropic Submaniolds Of A Space From, Takehiro Itoh, Koichi Ogiue

Turkish Journal of Mathematics

We study 3-dimensional isotropic submanifolds of a space form with low-dimensional first normal space


Cover And Contents Jan 1998

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Turkish Journal of Mathematics

No abstract provided.


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Turkish Journal of Medical Sciences

No abstract provided.


Cover And Contents Jan 1998

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Turkish Journal of Medical Sciences

No abstract provided.


The Effect Of Temperature Dependent Frequency Factor On The Evaluated Trapping Parameters Of Tsl Glow Curves, A. N. Yazici, Z. Öztürk Jan 1998

The Effect Of Temperature Dependent Frequency Factor On The Evaluated Trapping Parameters Of Tsl Glow Curves, A. N. Yazici, Z. Öztürk

Turkish Journal of Physics

The effect of temperature dependency on frequency factor and its relationship to trapping parameters is discussed by using the peak shape method. The coefficients appearing in the peak shape formula for the calculation of the activation energy have been determined and tabulated for the symmetry factor $\mu_g(X)$ for $x=0.50$ and 0.75 of the peak intensity. It is found that significant errors occur in the value of the trapping parameters if the temperature dependecy of the frequency factor is not consider.


Fine Structure Analysis Of 4702 ^Oa Band Of The Molecule, M.B. Sureshkumar, S.R. Srikant Jan 1998

Fine Structure Analysis Of 4702 ^Oa Band Of The Molecule, M.B. Sureshkumar, S.R. Srikant

Turkish Journal of Physics

The emission spectrum of the cobalt monochloride molecule has been excited in a high frequency discharge tube source and the (0,0) band of H-system at 4702 \AA was photo-graphed at an inverse dispersion of 0.973 \AA/mm in the 5th order of a two meter plane grating spectrograph (Carl-Zeiss). The fine structure analysis of the band has been carried out and the molecular constants are reported for the first time. Rotational isotopic shift due to $^{37}$Cl support the analysis. The electronic transition involved is of the type $0^-$----- $0^-$ of case (c) which is equivalent of $^{3}\sum^{+}$-----$^{3}\sum^+$ or $^5\sum^+$-----$^5\sum^+$.


Remote Sensing And Synchronous Land Surface Measurements Of Soil Moisture And Soil Temperature In The Field, N.V. Kolev, K.P. Penev, Y.M. Kirkova, B.S. Krustanov, T.G. Nazarsky, G.K. Dimitrov, C.P. Levchev, H.I. Prodanov, L.H. Kraleva Jan 1998

Remote Sensing And Synchronous Land Surface Measurements Of Soil Moisture And Soil Temperature In The Field, N.V. Kolev, K.P. Penev, Y.M. Kirkova, B.S. Krustanov, T.G. Nazarsky, G.K. Dimitrov, C.P. Levchev, H.I. Prodanov, L.H. Kraleva

Turkish Journal of Physics

The paper presents the results of remote sensing and synchronous land surface measurements for estimation of soil (surface and profile) water content and soil temperature for different soil types in Bulgaria. The relationship between radiometric temperature and soil surface water content is shown. The research is illustrated by some results from aircraft and land surface measurements carried out over three test areas near Pleven, Sofia and Plovdiv, respectively, during the period 1988-1990.


Cover And Contents Jan 1998

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Turkish Journal of Physics

No abstract provided.


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Turkish Journal of Biology

No abstract provided.


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Turkish Journal of Biology

No abstract provided.


Determination Of Emitter Spacing Based On The Amount Of Water Applied And Trickle Discharge Rates, Cafer Gençoğlan Jan 1998

Determination Of Emitter Spacing Based On The Amount Of Water Applied And Trickle Discharge Rates, Cafer Gençoğlan

Turkish Journal of Agriculture and Forestry

This study was conducted with the objectives of determining effect of trickle discharge rates and amount of irrigation water applied on water distribution in the soil profile and to estimate the emitter spacing by the Wooding method and wetting front in the wetted soil volume in a clay soil. Total volume irrigation water of 16, 32 and 64 L were applied with discharge rates of 2, 4, 6 and 8 L/h and water has moved laterally to a distance of 45-60 cm from the trickle source 48 hrs after water application. Result of this study indicated that as the flow …


Cover And Contents Jan 1998

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Turkish Journal of Agriculture and Forestry

No abstract provided.


Operation Research Methods In The Forest Management Planning, Altay Uğur Gül Jan 1998

Operation Research Methods In The Forest Management Planning, Altay Uğur Gül

Turkish Journal of Agriculture and Forestry

The purpose of this study is to approximate the actual forest state to an aptimal forest state within different conversion period lenghts, to ensure the sustainability of allowable cut over planning horizon, to maximize the total present net value calculated with financial analysis. A linear programming model was developed and used to test 436 different strategies for planning of Gazipasa Forest Management Unit. The value of the objective function of the solution that maximized the total present net value is 63352171000 TL and the amount of the total volume is 9054041 m3. For the first plan period, when the objective …


Cover And Contents Jan 1998

Cover And Contents

Turkish Journal of Agriculture and Forestry

No abstract provided.