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Obituary Prof. Dr. Orhan Kaya [4th October 1937-24th November 2002] By, Tanju Kaya Jan 2002

Obituary Prof. Dr. Orhan Kaya [4th October 1937-24th November 2002] By, Tanju Kaya

Turkish Journal of Earth Sciences

No abstract provided.


Obituary Prof. Dr. Kâzım Ergi̇n [21 May 1915-24 November 2002] By, Tuncay Taymaz Jan 2002

Obituary Prof. Dr. Kâzım Ergi̇n [21 May 1915-24 November 2002] By, Tuncay Taymaz

Turkish Journal of Earth Sciences

No abstract provided.


Cover And Contents Jan 2002

Cover And Contents

Turkish Journal of Biology

No abstract provided.


Cover And Contents Jan 2002

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Turkish Journal of Biology

No abstract provided.


Cover And Contents Jan 2002

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Turkish Journal of Mathematics

No abstract provided.


Cover And Contents Jan 2002

Cover And Contents

Turkish Journal of Mathematics

No abstract provided.


Cover And Contents Jan 2002

Cover And Contents

Turkish Journal of Mathematics

No abstract provided.


Cover And Contents Jan 2002

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Turkish Journal of Agriculture and Forestry

No abstract provided.


Cover And Contents Jan 2002

Cover And Contents

Turkish Journal of Agriculture and Forestry

No abstract provided.


Effects Of Perinatal Factors On The Duration And Cost Of Hospitalisation For Preterm Infants In A Neonatal Intensive Care Unit In Istanbul, İpek Akman, Di̇lşad Cebeci̇, Eren Özek, Sebahat İmamoğlu Jan 2002

Effects Of Perinatal Factors On The Duration And Cost Of Hospitalisation For Preterm Infants In A Neonatal Intensive Care Unit In Istanbul, İpek Akman, Di̇lşad Cebeci̇, Eren Özek, Sebahat İmamoğlu

Turkish Journal of Medical Sciences

Long hospitalisation and high hospital charges of premature infants are important concerns for parents and health providers. In this study we determined the length of stay and hospital cost of preterm babies and assessed the predictive value of perinatal factors on the duration and the cost of hospitalisation. We reviewed hospital charges and length of stay for a retrospective cohort of 72 premature infants discharged from the neonatal intensive care unit of Marmara University Hospital between January 1999 and January 2000. The perinatal factors were analysed using forward stepwise multiple linear regression analysis. The median gestational age and birth weight …


Cover And Contents Jan 2002

Cover And Contents

Turkish Journal of Biology

No abstract provided.


Cover And Contents Jan 2002

Cover And Contents

Turkish Journal of Biology

No abstract provided.


Cover And Contents Jan 2002

Cover And Contents

Turkish Journal of Biology

No abstract provided.


On The Spectral Properties Of The Regular Sturm-Liouville Problem With The Lag Argument For Which Its Boundary Conditions Depends On The Spectral Parameter, Mehmet Bayramoğlu, Kevser Özden Köklü, Oya Baykal Jan 2002

On The Spectral Properties Of The Regular Sturm-Liouville Problem With The Lag Argument For Which Its Boundary Conditions Depends On The Spectral Parameter, Mehmet Bayramoğlu, Kevser Özden Köklü, Oya Baykal

Turkish Journal of Mathematics

In this paper, the asymptotic expression of the eigenvalues and eigenfunctions of the Sturm-Liouville equation with the lag argument y''(t) + \lambda^2 y(t) + M(t)y (t - \Delta(t)) = 0 and the spectral parameter in the boundary conditions \lambda y(0) +y'(0) = 0 \lambda^{2}y(\pi) + y'(\pi) = 0 y(t - \Delta(t)) = y(0)\varphi(t - \Delta(t)), t - \Delta(t) < 0 has been founded in a finite interval, where M(t) and \Delta(t) \geq 0 are continuous functions on [0, \pi], \lambda > 0 is a real parameter, \varphi(t) is an initial function which is satisfied with the condition \varphi(0) = 1 and continuous in the initial set.


Age And Thickness Of The Lithosphere Within The Western And Eastern Basins Of The Black Sea According To Geophysical Data, Eugeniy Verzhbitsky, Ivan Kuzin, Leopold Lobkovsky Jan 2002

Age And Thickness Of The Lithosphere Within The Western And Eastern Basins Of The Black Sea According To Geophysical Data, Eugeniy Verzhbitsky, Ivan Kuzin, Leopold Lobkovsky

Turkish Journal of Earth Sciences

The ages of the western and eastern basins of the Black Sea have been estimated on the basis of heat-flow data. The obtained ages (70-60 Ma) are in good accord with the time of basins' origin as determined from seismic and magnetic data. During this time, the Black Sea opened as a back-arc basin to the north of the Pontide magmatic arc. The arc prehistory of the Pontides is confirmed by the existence of relict mantle seismicity, which is most active in the eastern Pontides. Nearly synchronous times of origin for the western and eastern basins supports the concept of …


Experimental Investigation Of Temperature Effect On Refractive Index Of Dye Laser Liquids, Şeref Yaltkaya, Ramazan Aydin Jan 2002

Experimental Investigation Of Temperature Effect On Refractive Index Of Dye Laser Liquids, Şeref Yaltkaya, Ramazan Aydin

Turkish Journal of Physics

In this work, refractive index of selected dye laser solutions were measured by fiber optic sensor. The fiber optic probe was dipped into the liquids and according to Fresnel's Reflection Law, refractive index values were obtained at the wavelength of the laser utilized. The solutions consisted of Rhodamine 6G, Rhodamine B and Coumarin 481 dissolved in methanol, and ethylene glycol, respectively. Refractive index variations of the dye solutions and their solvents with temperature were measured and the refractive index temperature coefficient dn/dT were calculated at the wavelength of 780 nm.


A Personel Note, Leopold B. Felsen Jan 2002

A Personel Note, Leopold B. Felsen

Turkish Journal of Electrical Engineering and Computer Sciences

No abstract provided.


Iterative Solution Of Field Problems With A Varying Physical Parameter, Anton G. Tijhuis, Martijn C. Van Beurden, A. Peter M. Zwamborn Jan 2002

Iterative Solution Of Field Problems With A Varying Physical Parameter, Anton G. Tijhuis, Martijn C. Van Beurden, A. Peter M. Zwamborn

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, linear field problems with a varying physical parameter are solved with the conjugate-gradient FFT method and a dedicated extrapolation procedure for generating the initial estimate. The scheme is formulated and illustrated for two simple example problems. The importance of the choice of the stop criterion and the step size are demonstrated for the case of a straight thin-wire segment. A brief summary is given of the applications that have appeared in the open literature until now, and actual three-dimensional scattering problems for a rectangular conducting plate and an inhomogeneous, dispersive dielectric body are discussed. Finally, the case …


Network--Oriented Modeling Of Radiating Electromagnetic Structures, Peter Russer Jan 2002

Network--Oriented Modeling Of Radiating Electromagnetic Structures, Peter Russer

Turkish Journal of Electrical Engineering and Computer Sciences

The application of network-oriented modeling for radiating electromagnetic structures is investigated. Network methods are applied to the field problem using the segmentation technique and by specifying canonical Foster representations as compact models of reciprocal linear lossless electromagnetic structures. Connection between different subdomains is obtained via connection circuits exhibiting only ideal transformers. In the case of radiating structures, the complete structure is embedded into a sphere and the field outside the sphere is expanded into orthogonal spherical TM- and TE- waves. For each radiation mode a Cauer canonic circuit representation is given.


Novel Time Domain Radiowave Propagators For Wireless Communication Systems, Funda Akleman, M. O. Özyalçin, Levent Sevgi̇ Jan 2002

Novel Time Domain Radiowave Propagators For Wireless Communication Systems, Funda Akleman, M. O. Özyalçin, Levent Sevgi̇

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, novel time domain wave propagators are used in path loss calculations for macro and micro cell coverage planning in wireless communication systems. Both Transmission Line Matrix (TLM) and Finite-Difference Time-Domain (FDTD) based propagators, which were introduced recently and validated and verified on different canonical propagation scenarios, are used for this purpose. Examples are chosen both in rural and urban areas, where two propagators are compared with each other. Excellent agreement between the results obtained via two propagators is presented. The results presented here are very encouraging and these propagators are shown to be powerful tools for not …


Floquet Wave Diffraction Theory For Tapered Planar Strip Array Green's Function, F. Capolino, F. Mariottini, S. Maci, L. B. Felsen Jan 2002

Floquet Wave Diffraction Theory For Tapered Planar Strip Array Green's Function, F. Capolino, F. Mariottini, S. Maci, L. B. Felsen

Turkish Journal of Electrical Engineering and Computer Sciences

This paper deals with the derivation and physical interpretation of a uniform high frequency representation of the Green's function for a planar phased array of dipoles. The asymptotic representation is based on Floquet wave edge diffraction theory herein extended to accommodate slowly varying tapered amplitude illumination with possible inclusion of dipole amplitudes that tend to zero at the edge. The phased array is assumed to be infinite with uniform amplitude excitation in the z-direction but finite and amplitude-tapered in the x-direction. This geometry permits study of diffraction phenomena occurring at the tapered edge of a rectangular array when the observation …


An Exact Line Integral Representation Of The Po Radiation Integral From A Flat Perfectly Conducting Surfaces Illuminated By Elementary Electric Or Magnetic Dipoles, Matteo Albani, Stefano Maci Jan 2002

An Exact Line Integral Representation Of The Po Radiation Integral From A Flat Perfectly Conducting Surfaces Illuminated By Elementary Electric Or Magnetic Dipoles, Matteo Albani, Stefano Maci

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a line integral representation for the PO radiation integral from a flat perfectly conducting surface, illuminated by an arbitrary oriented elementary either electric or magnetic dipole, is presented. No restriction is imposed on the position of the source and of the observation point. The main application of this result is the acceleration of the numerical PO integration for electrically large surfaces. The formulation is based on the application of the equivalence principle to a projecting surface which allows the analytical evaluation in closed form of one of the two-fold surface integral which define the radiated field at …


On The Modular Curve X(6) And Surfaces Admitting Genus 2 Fibrations, Gülay Karadoğan Jan 2002

On The Modular Curve X(6) And Surfaces Admitting Genus 2 Fibrations, Gülay Karadoğan

Turkish Journal of Mathematics

In this paper, we study the moduli spaces of surfaces admitting nonsmooth genus 2 fibrations with slope \lambda = 6 (necessarily) over curves of genus \geq 1. We determine the structure of each connected component of these moduli spaces. Our results fill the gap of earlier work in the literature to complete the picture of the moduli spaces of genus 2 fibrations over curves of genus \geq 2 except for the case of \lambda = 4.


Cover And Contents Jan 2002

Cover And Contents

Turkish Journal of Veterinary & Animal Sciences

No abstract provided.


Cover And Contents Jan 2002

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Turkish Journal of Veterinary & Animal Sciences

No abstract provided.


Cover And Contents Jan 2002

Cover And Contents

Turkish Journal of Veterinary & Animal Sciences

No abstract provided.


Cover And Contents Jan 2002

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Turkish Journal of Veterinary & Animal Sciences

No abstract provided.


Cover And Contents Jan 2002

Cover And Contents

Turkish Journal of Veterinary & Animal Sciences

No abstract provided.


Determination Of Cadmium By Faas After Solid-Phase Extraction Of Its 1-Benzylpiperazinedithiocarbamate Complex On Microcrystalline Naphthalene, Hasan Cesur, Beki̇r Bati Jan 2002

Determination Of Cadmium By Faas After Solid-Phase Extraction Of Its 1-Benzylpiperazinedithiocarbamate Complex On Microcrystalline Naphthalene, Hasan Cesur, Beki̇r Bati

Turkish Journal of Chemistry

By using 1-benzylpiperazinedithiocarbamate (1-BPzDC) as a new reagent, a method of solid-phase extraction is described for the pre-concentration of cadmium in water samples prior to its determination by flame atomic absorption spectrometry (FAAS). This method is based on the fact that cadmium forming in aqueous phase cadmium 1-benzylpiperazinedithiocarbamate complex (Cd(1-BPzDC)_{2}) can be extracted with microcrystalline naphthalene on solid phase, then back-extracted with potassium cyanide solution into aqueous phase and measured by FAAS. The optimum experimental parameters for the extraction and back-extraction of cadmium were investigated. The obtained recovery was nearly 97% when the enrichment factor was 500 for spiked cadmium …


Iridoid, Phenylethanoid And Monoterpene Glycosides From Phlomis Sieheana, Tayfun Ersöz, Ü. Şebnem Harput, İhsan Çaliş, Ali̇ Arslan Dönmez Jan 2002

Iridoid, Phenylethanoid And Monoterpene Glycosides From Phlomis Sieheana, Tayfun Ersöz, Ü. Şebnem Harput, İhsan Çaliş, Ali̇ Arslan Dönmez

Turkish Journal of Chemistry

From the aerial parts of Phlomis sieheana, an iridoid glucoside, ipolamiide (1), six phenylethanoid glycosides, acteoside (= verbascoside) (2), cis-acteoside (3), \beta-hydroxyacteoside (4), leucosceptoside A (5), martynoside (6), forsythoside B (7), and a monoterpene glycoside, betulalbuside A (8) were isolated and characterized. The structure elucidations of the isolated compounds were established on the basis of spectroscopic evidence.