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61.
62.
The nuclear data on (α, xn) reactions are very important in the fields of radiation shielding, long-term safe handling of spent fuel and spallation neutron-production. In this study, neutron-production cross sections have been calculated for some target nuclei such as 65Cu and 209Bi. Hybrid model and geometry dependent hybrid model have been used to calculate the pre-equilibrium neutron-production cross sections. The mean free path parameter’s effect for (α, xn) neutron-production cross section has been examined. The obtained results have been discussed and compared with the available experimental data. 相似文献
63.
G. Aydin 《Petroleum Science and Technology》2013,31(15-16):1486-1492
Natural gas is an important energy sources governing the world economy. Therefore, accurate forecasting models for its production rate are needed to provide better planning. In the present study, various modeling approaches are used to model global natural gas production (NGP). The regression models developed are validated using some statistical approaches. The developed models are then compared using a test data set which is not utilized during construction of models. Mean absolute percentage error is used for comparing the developed modes. The results reveal that proposed models are capable of giving adequate prediction for the NGP with an acceptable accuracy level. Additionally, the compared results show that the S regression model is more reliable than the other regression models. 相似文献
64.
E. Tel A. A. Gok M. Sahan İ. H. Sarpun Y. Kavun A. Aydin 《Journal of Fusion Energy》2017,36(4-5):173-177
In this study, calculation of charged particles induced nuclear reactions of beryllium (9Be) target nuclei have been investigated in the incident proton and alpha at energy range from threshold to 50 MeV. The excitation functions for 9Be target nuclei reactions have been calculated by using PCROSS nuclear reaction calculation code. Weisskopf–Ewing model for equilibrium, calculations and the full exciton and cascade exciton models for pre-equilibrium calculations were used. Also, the semi-empirical calculations for (p,α) reactions have been done by using cross section formula updated with new coefficient developed by Tel et al. (Pramana Indian Acad Sci 74(6):931, 2010). The calculated results were compared with the experimental data for different energy levels ranging from 0.00 to 9.65 MeV taken from the literature. 相似文献
65.
In this correspondence, the problem of directional and multiscale edge detection is considered. Orthogonal and linear-phase M-band wavelet transform is used to decompose the image into MxM channels. These channels are then combined such that each combination, which we refer to as decomposition filter, results in zero-crossings at the locations of edges corresponding to different directions and resolutions, and inherently performs regularization against noise. By applying a zero-crossing detector on the outputs of the decomposition filters, edge maps of desired resolution and direction are obtained. In addition, with the application of the Teager's energy operator at the analysis stage, it is possible to obtain a reduction in unwanted zero-crossings. Final edge maps of images are obtained through simple combinations of directional edge maps. 相似文献
66.
A method for normalization of Schmidt hammer rebound values 总被引:1,自引:0,他引:1
67.
In 4 experiments rats received appetitive Pavlovian conditioning followed by extinction. Food accompanied every trial with the conditioned stimulus (CS) for the continuously reinforced groups and only half of the trials for the partially reinforced groups. In contrast to previous experiments that have compared the effects of partial and continuous reinforcement, the rate at which food was delivered during the CS was the same for both groups. The strength of the conditioned response during extinction weakened more rapidly in the continuously than in the partially reinforced groups. The results demonstrate that the partial reinforcement extinction effect is a consequence of the nonreinforced trials with the CS, rather than the rate at which the unconditioned stimulus is delivered during the CS. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
68.
H Vahaboglu R Oztürk G Aygün F Co?kunkan A Yaman A Kaygusuz H Leblebicioglu I Balik K Aydin M Otkun 《Canadian Metallurgical Quarterly》1997,41(10):2265-2269
We studied the prevalence and molecular epidemiology of PER-1-type beta-lactamases among Acinetobacter, Klebsiella, and Pseudomonas aeruginosa strains isolated over a 3-month period in eight university hospitals from distinct regions of Turkey. A total of 72, 92, and 367 Acinetobacter, Klebsiella, and P. aeruginosa isolates were studied, respectively. The presence of blaPER was determined by the colony hybridization method and later confirmed by isoelectric focusing. We detected PER-1-type beta-lactamases in 46% (33/72) of Acinetobacter strains and in 11% (40/367) of P. aeruginosa strains but not in Klebsiella strains. PER-1-type enzyme producers were highly resistant to ceftazidime and gentamicin, intermediately resistant to amikacin, and susceptible or moderately susceptible to imipenem and meropenem. Among PER-1-type-beta-lactamase-positive isolates, five Acinetobacter isolates and six P. aeruginosa isolates from different hospitals were selected for ribosomal DNA fingerprinting with EcoRI and SalI. The EcoRI-digested DNAs were later hybridized with a digoxigenin-labelled PER-1 probe. The ribotypes and the lengths of blaPER-carrying fragments were identical in four Acinetobacter strains. A single isolate (Ac3) harbored a PER gene on a different fragment (approximately 4.2 kbp) than the others (approximately 3.4 kbp) and showed a clearly distinguishable ribotype. Ribotypes of P. aeruginosa strains obtained with EcoRI showed three patterns. Similarly, in Pseudomonas strains two different EcoRI fragments harbored blaPER (approximately 4.2 kbp in five isolates and 3.4 kbp in one isolate). PER-1-type beta-lactamases appear to be restricted to Turkey. However, their clonal diversity and high prevalence indicate a high spreading potential. 相似文献
69.
I Hamzao?lu T Karahasano?lu S Aydin DA Sahin S Carkman M Sariyar K Alemdaro?lu 《Canadian Metallurgical Quarterly》1998,176(5):458-461
A pregnant woman with transient gastric obstruction was fed by enteral nutrition alone for 11 wk and 6 d. Her body mass index of 23.2 kg/m2 before pregnancy declined to 21.8 kg/m2 after delivery. Although she did not gain weight during enteral nutrition, fetal growth, estimated by ultrasonography, was normal, and she delivered a 3030-g female infant at 38 wk gestation. The blood laboratory data during pregnancy and the breast milk after pregnancy were also normal. The results suggest that factors other than maternal weight gain alone should be considered in the evaluation of nutritional status for the pregnant woman. 相似文献
70.
This paper addresses new hop-timing (epoch) estimation schemes which employ a coarsely channelized preprocessor in order to suppress the frequency and phase dependence in random frequency-hopping (FH) signals. Coarse channelization implies a bank of filters, covering the total spread bandwidth of the FH signal, whose number is much smaller than the size of the candidate hop frequency set. Linear and nonlinear combinations of preprocessor outputs are explored and compared. It is found that post-processing, rather than the size of the filter bank alone, is the determining factor on estimation performance. Performance evaluation is presented via both extensive computer simulations and analytical lower bounds. Comparisons with existing optimal and suboptimal systems are also provided 相似文献