Yazar "Arslan H." seçeneğine göre listele

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    Ab initio studies on 5-Bromo-10-oxa-3-thiatricyclo[5.2.1.0 1,5]-Dec-8-ene3,3-dioxide
    (2007) Arslan H.; Demircan A.
    5-Bromo-10-oxa-3-thiatricyclo[5.2.1.01,5]-dec-8-ene 3,3-dioxide (BOTCDO) was synthesized from the reaction between 2-(2- bromoallylsulfanylmethyl)-furan and m-chloroperbenzoic acid in dichloromethane. The molecular structure and vibrational frequencies of BOTCDO in the ground state have been investigated with ab initio (HF) and density functional theory methods (B3LYP, B3PW91 and MPW1PW91) implementing the standard 6-31G(d) basis set. The optimized geometric bond lengths and bond angles obtained by using HF and DFT methods show the best agreement with the experimental data. Comparison of the observed fundamental vibrational frequencies of title compound and calculated results by HF and DFT methods indicate that MPW1PW91 is superior to the scaled HF approach for molecular problems. Optimal uniform scaling factors calculated for the title compound are 0.8920, 0.9553, 0.9518 and 0.9452 for HF, B3LYP, B3PW91 and MPW1PW91 methods, respectively.
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    Determination of trace metal content of Gokceada curing mud bath by AAS
    (1998) Özpozan T.; Özpozan N.; Arslan H.
    Trace metal ion concentrations of the mud bath of the Gokceada region were investigated to determine Cr, Pb, Bi, Ni, Cu, Fe, Mn, Zn, Cd, Ca, Mg, Ba and As content by AAS. The concentrations of Cr and Cd were found below the detection limit of flame AAS so they could not be determined. Mg and Ca were higher in concentrations, as expected, and Co, Cu and Ni were the lowest detectable quantities in the samples measured by Flame AAS.
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    Hybrid precoding for mmWave massive MIMO systems with generalized triangular decomposition
    (Institute of Electrical and Electronics Engineers Inc., 2018) Kabalci Y.; Arslan H.
    Hybrid precoding schemes have recently gained a great attention for millimeter wave (mmWave) massive multiple-input-multiple-output (massive MIMO) communication systems because of offered cost and low-power consumption advantages. The singular value decomposition (SVD) method which is exploited in the design of hybrid precoding causes several problems on system design, especially on bit allocation, precoding and equalizing processes. On the other hand, the previous works show that generalized triangular decomposition (GTD) method can present asymptotically optimal performance in conventional MIMO systems. In the light of this, we propose the use of GTD method for designing hybrid precoding operating in mmWave massive MIMO systems. The proposed design is analyzed via performed simulation studies including different system configurations. Moreover, the archived results are compared with the standard orthogonal matching pursuit (OMP) algorithm based hybrid precoding scheme. The simulation results show that the proposed hybrid precoding scheme can reach up to the performance of optimal precoding scheme. © 2018 IEEE.