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1.
In 2007, Bohli et al. (Int J Inf Secur 6:243–254, 2007) proposed a two-round group key agreement protocol in the random oracle model, which in addition to semantic security offers strong entity authentication and a security guarantee against malicious insiders. We suggest a modification of this protocol that preserves the security guarantees and the round complexity, but reduces the amount of data that has to be sent and also reduces the number of signature computations and verifications by 50 %. Moreover, we propose a variant of Bohli et al.’s protocol whose security analysis does not require a random oracle or other idealizing assumptions.  相似文献   
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Here we describe a new procedure for ascospore isolation from cultures containing a majority of unsporulated vegetative cells of Saccharomyces cerevisiae. The EZ ascospore isolation procedure relies on the combination of two conventional protocols, diethyl ether treatment and modified zymolyase treatment, allowing a significant increase in the efficiency of ascospore isolation and consequently enabling a large number of meiotic offspring to be efficiently obtained and screened, thus improving the efficacy of genetic research and the genetic selection of S. cerevisiae strains. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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A processing method called “accelerated mild anodization” is developed for preparation of high density and uniform nanoporous by anodization of aluminum. The idea is to use two different temperatures for both sides of sample in order to maintain mid level of current density during the anodization process. Here we have used high temperature for the back side of the sample in order to increase the current density while the electrolyte is kept at low temperature in the level of mild anodization. It is shown that not only the film growth is considerably fast, almost ten times faster than mild anodization, but also the anodization voltage is constant and anodization current variation is much less compared to hard anodization technique. Using oxalic acid, interpore distances of 89, 104, 117 and 130 nm were obtained for 35, 40, 45 and 50 V anodization voltages, respectively. It is found that the interpore distances are proportional to the anodization potential, almost same as that for the mild anodization. The porosity obtained tended to obey the same rule as that in mild anodization. This method is promising for industrial application due to short fabrication time as well as high-speed pore ordering.  相似文献   
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环境噪声处理不当或者传感器数目少于故障数目都可能导致基于源分离的复合故障诊断失败,针对此问题,提出了基于改进样板去噪源分离的诊断方法并用于轴承复合故障诊断。该方法首先对数据进行移动独立分量分析,然后将得到的独立成分作为输入样板进行样板去噪源分离。轴承复合故障的仿真和实验数据分析证明,该方法能够在未知噪声环境下完成传感器数目少于故障数目的欠定源分离,该方法对轴承复合故障诊断是有效的。  相似文献   
5.
This prospective study investigated the urodynamics of the urinary bladder prior to renal transplantation in 57 patients and related this to graft function and transplantation outcome. The study demonstrated a clear deterioration in the pretransplant urodynamic characteristics in all subgroups, with male patients in the hemodialysis group (HD) showing a more substantial decline: 1st sensation volume (ml) in male HD patients = 112 (120) vs. 171 (173) in male CAPD patients, P < 0.05; and corresponding average flow rate for same groups 3 (3) ml/sec vs. 5 (5) ml/sec, P < 0.05. Figures are median (interquartile range). We have identified a subgroup of patients with a small bladder capacity (less than 100 ml) who have a reduced graft survival (55% vs. 92% for bladders larger than 100 ml at 2 years) apparently unrelated to immunological processes.  相似文献   
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Wireless Personal Communications - Faster development of smart electronic devices in recent years along with significant increase in demanding higher data rates has made cognitive radio networks...  相似文献   
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An accelerated aging study on silicone rubber exploring the effects of exposure to a functional oil (polyalkylene glycol) at elevated temperature (195°C) is reported in this paper. Variations in mechanical (tensile, tear, hardness) and thermal (conductivity, specific heat capacity) properties were monitored versus aging time while permanent deformation of the rubber was evaluated through creep and recovery measurements. Morphology and surface chemistry of the aged rubber were also investigated through scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy, respectively. Aging had a significant impact on the mechanical properties with the ultimate tensile strength and elongation at break decreasing from 7.4?MPa and 2250% in unaged samples to 1.5?MPa and 760% in 6-week aged samples, respectively. The tear strength and hardness exhibited an initial increase during the early stages of aging, followed by a decreasing trend. In contrast, the thermal properties did not change significantly and FTIR did not detect any changes in the surface chemistry of the rubber with aging. SEM however, provided evidence of an increase in brittle behavior from the morphology of the fractured surfaces.  相似文献   
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