Now showing items 21-40 of 24387

    • Efficiency calibration and summation effects in gamma-ray spectrometry 

      Erten, H. N.; Aksoyoğlu, S.; Göktürk, H. (Kluwer Academic Publishers, 1988)
      Precise, absolute γ-ray efficiences (∈γ) and total efficiences (∈T), have been measured at various distances from the detector, using a set of standards. The observed linear variation of ∈γ and ∈T as well as ∈γ/∈T with Eγ ...
    • Sequential decoding for multiple access channels 

      Arıkan, E. (Institute of Electrical and Electronics Engineers, 1988)
      The use of sequential decoding in multiple access channels is considered. The Fano metric, which achieves all achievable rates in the one-user case, fails to do so in the multiuser case. A new metric is introduced and an ...
    • An Upper Bound on the Cutoff Rate of Sequential Decoding 

      Arikan, E. (1988)
      An upper bound is given on the cutoff rate of discrete memoryless channels. This upper bound, which coincides with a known lower bound, determines the cutoff rate, and settles a long-standing open problem. © 1988 IEEE
    • Calculations of STM linescans-general formalism 

      Ellialtioğlu, Ş.; Ciraci, S.; Batra, I. P. (Pergamon Press, 1988)
      We have developed a formalism for calculating the line scans of the scanning-tunneling microscopy from the realistic substrate and tip wave functions. The tip wave functions are calculated self-consistently by using a ...
    • A fast method of calculating diffraction loss between two facing transducers 

      Atalar, Abdullah (IEEE, 1988)
      A fast method of calculating the diffraction loss between two facing circular ultrasonic transducers of unequal size is presented. This problem is directly applicable for minimization of diffraction loss in acoustic lens ...
    • A heuristic procedure for a single-item dynamic lot sizing problem 

      Benli, O. S.; Sabuncuoglu, I.; Tufekci, S. (Pergamon Press, 1988)
      An O(T) heuristic proceudre for a single-item dynamic lot sizing problem is introduced in this paper. The algorithm tries to establish the regeneration points of the problem whether either the production or the beginning ...
    • Effect of tip profile on atomic-force microscope images: a model study 

      Abraham, F. F.; Batra, I. P.; Ciraci, S. (American Physical Society, 1988)
      Adopting the empirical silicon interatomic potential of Stillinger and Weber, we investigate the effect of the tip profile on the atomic-force microscope images for a prototype system, Si(001)-(2×1), and conclude that the ...
    • A simple animation package 

      Coşar, A.; Özgüç, B. (Pergamon Press, 1988)
      This paper discusses a simple animation package that animates sketches drawn by the user through a simple set of operations. The purpose of the animation package is to demonstrate various computer graphics principles to ...
    • A transportation type aggregate production model with bounds on inventory and backordering 

      Erenguc, S. S.; Tufekci, S. (Elsevier, 1988)
      We consider a certain T period aggregate production planning model, where the two sources of production are regular and overtime. The model allows for time varying production, holding and backordering costs and includes ...
    • Sorption of cesium and strontium on montmorillonite and kaolinite 

      Erten, H. N.; Aksoyoglu, S.; Hatipoglu, S.; Göktürk, H. (De Gruyter Oldenbourg, 1988)
      Sorption characteristics of Cs+ and Sr++on montmorillonite and kaolinite type clays and soil fractions from various regions of Turkey were studied using the batch method. 137Cs and 90Sr were used as tracers. Concentrations ...
    • Delta-Doping in strained (Si) / (Ge) superlattices 

      Ciraci, S.; Batra, I. P.; Tekman, E. (American Physical Society, 1988)
      We present a comparative study of the pseudomorphic (Si)6/(Ge)6 and -doped (Si)3(Sb)(Si)2/(Ge)6 superlattices using the self-consistent pseudopotential method. The strained (Si)6/(Ge)6 superlattice has the lowest conduction-band ...
    • An isomorphism theorem for Dragilev spaces 

      Kocatepe, M. (Birkhäuser-Verlag, 1988)
      Necessary and sufficient conditions for an Ly(a, l)-space to be isomorphic to some Lg(b, m)-space have been found.
    • Critical relaxation of the two-dimensional three-state Potts model with conserved dynamics 

      Aydın, M.; Yalabık, M. C. (Institute of Physics (Great Britain), 1988)
      The dynamical critical exponent z is obtained using the finite-size scaling method for the two-dimensional three-state Potts model with conserved dynamics. It is observed that there is a change in the dynamical behaviour ...
    • Surface metallization of silicon by potassium adsorption on Si(001)-(2×1) 

      Ciraci, S.; Batra, I. P. (American Physical Society, 1988)
      We present the detailed results of self-consistent and geometry-optimized total-energy, band-structure, and charge-density calculations for a potassium-covered Si(001)-(2×1) surface, and for an unsupported potassium ...
    • Electronic structure of strained Sin / Gen (001) superlattices 

      Ciraci, S.; Gülseren, O.; Ellialtioğlu, Ş. (Pergamon Press, 1988)
      Using the empirical tight binding method we have investigated the electronic properties of the Sin/Gen(001) strained superlattices as a function of the superlattice periodicity and the band misfit. For n ≥ 4 we have found ...
    • Marketing research in Saudi Arabia 

      Tuncalp, Seçil (Emerald, 1988)
      The marketing research scene in Saudi Arabia is investigated, where a number of environmental factors make marketing research a formidable undertaking. Cultural factors, such as language, religion and social etiquettes, ...
    • Tip induced localized states in scanning tunneling microscopy 

      Tekman, E.; Ciraci, S. (Institute of Physics Publishing Ltd., 1988)
      We have investigated the Scanning Tunneling Microscopy (STM) of graphite with varying tip-to-surface distance. Using an LCAO type approach we showed that at small separations states are localized between the tip and the ...
    • Sorption/desorption of Cs on clay and soil fractions from various regions of Turkey 

      Erten, H. N.; Aksoyoglu, S.; Göktürk, H. (Elsevier, 1988)
      The sorption desorption behaviour of Cs ion in the concentration region of 10−8 to 10−4 meqml−1 have been studied using clay and soil fractions from various regions of Turkey. The sorption curves for all the material studied ...
    • Seabed propagation of ULF/ELF electromagnetic fields from harmonic dipole sources located on the seafloor 

      Fraser-Smith, A. C.; lnan, A. S.; Villard, O. G.; Joiner, R. G. (Wiley-Blackwell Publishing, 1988)
      he amplitudes of the quasi-static electromagnetic fields generated at points on the seafloor by harmonic dipole sources (vertically directed magnetic dipoles, horizontally directed magnetic dipoles, vertically directed ...
    • Iterative algorithms for solution of large sparse systems of linear equations on hypercubes 

      Aykanat, C.; Özgüner, F.; Ercal, F.; Sadayappan, P. (IEEE, 1988)
      Finite-element discretization produces linear equations in the form Ax=b, where A is large, sparse, and banded with proper ordering of the variables x. The solution of such equations on distributed-memory message-passing ...