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951.
952.
Collusion attacks are a major issue in fingerprinting schemes for copyright protection. A new class of codes, called scattering codes, is presented which can be used to control colluders' strategy in collusions of size up to 3. Scattering codes can be combined with dual Hamming codes to obtain 3-secure fingerprinting codes much shorter than those resulting from Boneh-Shaw's general construction  相似文献   
953.
The purpose of this paper is to study the relationship between the oxygen concentration and brightness degradation in ZnS:TbOF green thin-film electroluminescent (EL) devices. The characteristics including crystallinity, optical, and electrical properties were discussed. The brightness-voltage (B-V) measurement results shelved that with higher oxygen-content in ZnS:TbOF phosphor layer, lower brightness was measured. It was consistent with the poor crystallinity, worse photoluminescent intensity, and easier to get moisture in the oxygen-rich (O/Tb>1) phosphor film. Furthermore, deep level transient spectroscopy (DLTS) measurements identified that when the O/Tb ratio was greater than 1, the oxygen-related deep hole traps EH1 and/or EH2 could be detected in the ZnS:TbOF phosphor layer. These E H1 and/or EH2 traps were believed to be the main killers for the brightness of the device since they capture most of the holes from the generated electron-hole pairs. This evidence strongly supports that the modified energy transfer model is more dominant than direct impact excitation during the luminescent process  相似文献   
954.
Two hundred twenty-eight patients with successful coronary stent implantation were randomized either to protamine administration and femoral sheath removal (group I, n = 117) or no heparin neutralization and delayed sheath removal (group II, n = 111). The hospital stay after treatment was shorter in patients receiving protamine; therefore, protamine use for neutralizing circulating heparin may be safely administered immediately after stent implantation.  相似文献   
955.
Two chronic haemodialyzed patients with digitalis intoxication are reported. One of them took digoxin 0.25 mg three times daily for an unknown period and the other took digitoxin 0.1 mg twice daily for two weeks. The symptoms of intoxication were mainly concealed by uremic syndrome. The diagnosis was established by noticed sinus bradycardia, first- and second-degree atrioventricular block in ECG and the determination of sera levels of glycosides (serum digoxin concentration was 7.36 ng/ml, serum digitoxin concentration was 46.5 ng/ml) in both cases. Considering the probable long elimination period of digitalis and the potentially life-threatening situation the patients were given digoxin-specific antibody (Fab) fragments with potassium replacement therapy. The symptoms disappeared within a few hours after therapy, side effects and rebound toxicity did not develop. In connection with these cases the aim of this report is to publish a method which can reverse the life-threatening digitalis intoxication in patients suffering from renal failure as well. As to the above method, the authors have not found any similar case reports in the Hungarian medical literature.  相似文献   
956.
We consider the task of partitioning the zeros of a real or complex polynomial into clusters and of determining their location and multiplicity for polynomials with coefficients of limited accuracy. We derive computational procedures for the solution of this task which combine symbolic computation with floating-point arithmetic. The validation of the existence ofmzeros in a specified small disk is described.  相似文献   
957.
958.
Dynamic modeling of lung C18O diffusion is used to measure the C18O transfer factor (TLco) of 14 newborns aged 1-4 mo. The model equation is based on the alveolar fractions of C18O and on changing alveolar ventilation induced by the rebreathing conditions. The model does not involve the volume of the rebreathing bag which is usually needed when applying rebreathing technique add which is a source of error. The equation is discretized and solved for recorded data obtained with equipment adapted to use in newborns. A least-square parameter calculation technique is applied to estimate TLco. Results show a strong relationship between this index and the biometrical ones and confirm those found in the literature featuring that the measurement duration can be considerably shortened  相似文献   
959.
A new method is presented for computing the electric lead field of a realistic head shape model which has piecewise homogenous conductivity. The basic formulae are derived using the well-known reciprocity theorem. Previously described methods are also based upon this theorem, but these first calculate the electric potential inside the head by a scalar boundary element method (BEM), and then approximate the ohmic current density by some sort of gradient. In contrast, this paper proposes the direct evaluation of the ohmic current density by discretizing the vector Green's second identity which leads to a rector version of BEM. This approach also allows the derivation of the same equations for the three concentric spheres model as obtained by Rush and Driscoll (1969). The results of simulations on a spherical head model indicate that the use of a vector BEM leads to an improvement of accuracy in the computation of the ohmic current density with respect to those reported previously, in term of different measures of error  相似文献   
960.
Stochastic complexity measures for physiological signal analysis   总被引:26,自引:0,他引:26  
Traditional feature extraction methods describe signals in terms of amplitude and frequency. This paper takes a paradigm shift and investigates four stochastic-complexity features. Their advantages are demonstrated on synthetic and physiological signals; the latter recorded during periods of Cheyne-Stokes respiration, anesthesia, sleep, and motor-cortex investigation  相似文献   
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