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31.
The influence of cultural factors on scientific production 总被引:2,自引:0,他引:2
A classification of countries is made according to respective ranks in the scales of publications per million persons and GDP per capita (ppp). The result is a clustering of countries which share a common cultural attitude toward scientific research. 相似文献
32.
Sotiriadis P.P. Celik A. Loizos D. Zhaonian Zhang 《IEEE transactions on circuits and systems. I, Regular papers》2007,54(1):218-228
A fast, one-pass harmonic-distortion estimation algorithm for G m-C filters is introduced. It is derived using state-space modeling and can be applied directly to Gm-C filters, of any order, with MOS transconductors exhibiting any type of weak nonlinearity. The algorithm is formed out of a small number of explicit expressions involving the filter's structural matrices and the transconductors' nonlinearity. It can be easily implemented in MATLAB. For verification of the theoretical development, the algorithm was used to derive the harmonic distortion of a single-ended Gm-C filter with weakly nonlinear transconductors designed on a 0.5-mum technology. The results of the algorithm and CADENCE simulation were found to be in good agreement 相似文献
33.
SENDROM is a new sensor network architecture to manage the rescue operations after large scale disasters. This architecture mainly consists of sensor nodes deployed prior to a disaster and central nodes that can query sensor nodes. Central nodes are stored nearby the emergency operation centers and airports before a disaster. Following a disaster rescue teams are assigned one mobile central node and guided to a region based on the data in the SENDROM database. This paper explains the SENDROM architecture as well as our new task and data dissemination, localization of a detected person, and end-to-end reliable event transfer schemes introduced for SENDROM. Then it evaluates the performance of these schemes analytically and through simulation. 相似文献
34.
Sule Erten-Ela Sadik Cogal Gamze Celik Cogal 《Fullerenes, Nanotubes and Carbon Nanostructures》2016,24(6):380-384
Poly(3,4-ethylenedioxxythiophene) (PEDOT), polyaniline (PANI) and polythiophene (PTh) based multi-walled carbon nanotube (MWCNT) composites were successfully prepared using RF-rotating plasma grafting method. Morphological characterizations of composites were determined using scanning electron microscopy (SEM), which showed that conducting polymers (CPs) of PEDOT, PANI and PTh were coated on the surface of CNTs. The surface properties of the Carbon Nanotube (CNT) composites were also determined by using Infrared Spectra (FT-IR), X-ray Photon Spectra (XPS), and Scanning Electron Microscopy-Energy Dispersive X-ray Spectra (SEM-EDX) analysis. X-ray photon spectra results confirmed the formation of the composites. Composites of MWCNT were used in dye-sensitized solar cells (DSSCs) as counter electrodes and exhibited short-circuit photocurrent densities of 11.19, 10.70 and 8.54 mA/cm2 for PANI/MWCNT, PTh/MWCNT and PEDOT/CNT, respectively. 相似文献
35.
The strong relationship between bank failure and economic growth attaches far more importance to the predictability of bank failures. Consequently, numerous statistical prediction models exist in the literature focusing on this particular subject. Besides, artificial intelligence techniques began to attain an increasing level of importance in the literature due to their predictive success. This study distinguishes itself from the similar ones in the sense that it presents a comparison of three different artificial intelligence methods, namely support vector machines (SVMs), radial basis function neural network (RBF-NN) and multilayer perceptrons (MLPs); in addition to subjecting the explanatory variables to principal component analysis (PCA). The extent of this study encompasses 37 privately owned commercial banks (17 failed, 20 non-failed) that were operating in Turkey for the period of 1997–2001. The main conclusions drawn from the study can be summarized as follows: (i) PCA does not appear to be an effective method with respect to the improvement of predictive power; (ii) SVMs and RBF demonstrated similar levels of predictive power; albeit SVMs was found to be the best model in terms of total predictive power; (iii) MLPs method stood out among the SVMs and RBF methods in a negative sense and exhibits the lowest predictive power. 相似文献
36.
Ferda Seyhan Guner OzaySena Saklar Erdal ErtaşGülçin Satır Cesarettin Alasalvar 《Food chemistry》2007,105(2):590-596
Three native hazelnut varieties from Turkey, namely, Tombul, Palaz, and Badem, were examined for their proximate composition, minerals, and fatty acid profiles, as well as polyphenol oxidase (PPO), peroxidase (POD), and lipase activities during fruit development stages (early stage: ES, middle stage: MS, and harvest stage: HS). Proximate composition varied considerably (dry weight basis) from ES to MS. Fat was the predominant component at all stages and showed increasing trends. Six essential minerals (calcium, iron, magnesium, phosphorus, potassium, and zinc) were analysed (dry weight basis). Consuming recommended daily amount of 42.5 g hazelnut at HS supplies 23.3–25.0% of phosphorus, 11.6–18.1% of magnesium, 7.0–18.9% of iron, 4.9–8.9% of zinc, 5.1–5.7% of calcium, and 5.1–5.3% of potassium for recommended dietary allowances or adequate intake for adults. Significant (P < 0.05) decreasing trends were found in all mineral contents from early development to maturity, with some exceptions. Sixteen fatty acids were identified, among which 18:1ω9 was by far the most predominant one, followed by 18:2ω6, 16:0, and 18:0. As expected, total monounsaturated fatty acids constituted the main group of fatty acids ranging from 75.51 to 81.07% in Tombul, from 78.21 to 82.71% in Palaz, and from 73.69 to 81.65% in Badem through the maturation stages. In contrast, total polyunsaturated fatty acids showed decreasing trends from ES to HS. No significant changes (P > 0.05) were observed in total saturated fatty acids at different maturation stages. Tombul variety had the lowest PPO activity compared to those of Palaz and Badem. Badem showed highest POD activity compared to Tombul and Palaz at three stages of maturation and significant decreases (P < 0.05) in all hazelnut samples were observed in POD activity from ES to HS. No lipase activity was detected in any hazelnut samples at ES and MS, except in Badem at MS. In contrast, lipase activity was detected in all hazelnut samples at HS. These results suggest that some proximate compositions, minerals, and fatty acids gave good indications during fruit development stages, whereas enzymatic activities of PPO, POD, and lipase behaved differently among varieties and fruit development stages. 相似文献
37.
K. Erdal 《Journal of the Institute of Brewing》1986,92(3):220-224
Colloidal haze in beer is due to the precipitation of proteins by proanthocyanidins. Carlsberg Research Center reported in 1977 that the use of barley mutants which block the biosynthesis of catechins and proanthocyanidins in the grain prevents the formation of haze in beer. The results from ten years of malting and brewing research with proanthocyanidin-free barley and malt are reviewed. 相似文献
38.
TA Serel G Akhan HR Koyuncuo?lu A Oztürk K Do?ruer S Unal K Celik 《Canadian Metallurgical Quarterly》1997,31(6):537-539
The treatment and favorable outcome of a bitch with uterine torsion and two retained fetuses are described. The condition was corrected surgically by ovariohysterectomy. Complications (i.e., septic shock, peritonitis, and hemostatic abnormalities) were managed with aggressive medical therapy. Torsion of the gravid uterus in dogs is a life-threatening condition which can have a successful outcome if medical complications encountered in the pre- and postoperative periods are treated quickly and effectively. 相似文献
39.
40.
Skoric B. Vladimirova T.U. Celik M. Talstra J.C. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2008,54(8):3663-3676
Tardos has proposed a randomized fingerprinting code that is provably secure against collusion attacks. We revisit his scheme and show that it has significantly better performance than suggested in the original paper. First, we introduce variables in place of Tardos' hard-coded constants and we allow for an independent choice of the desired false positive (FP) and false negative (FN) error rates. Following through Tardos' proofs with these modifications, we show that the code length can be reduced by more than a factor of two in typical content distribution applications where high FN rates can be tolerated. Second, we study the statistical properties of the code. Under some reasonable assumptions, the accusation sums can be regarded as Gaussian-distributed stochastic variables. In this approximation, the desired error rates are achieved by a code length twice shorter than in the first approach. Overall, typical FP and FN error rates may be achieved with a code length approximately five times shorter than in the original construction. 相似文献