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961.
962.
虚拟可信平台层次化安全体系结构设计 总被引:1,自引:0,他引:1
针对虚拟化技术给计算平台带来的一些新的安全问题,提出一种以虚拟机应用安全为核心的虚拟可信计算平台安全体系结构,为计算平台建立一种层次化的可信计算基(TCB):由硬件信任根TPM/TCM支持、可信虚拟机监控器(TVMM)以及安全管理器(SM)由底至上3个层次共同组成.基于开源XEN,设计了一种可保证虚拟机(VM s)及其应用安全的虚拟可信平台实例,它支持远程证实、信息流控制、安全迁移和私密性保护等安全机制.分析结果表明,实例系统可灵活支持其上虚拟机应用实现不同安全目标. 相似文献
963.
HA/TCP and HA rods (?5 mm×10 mm) were made for implantation in New Zealand white rabbit with different condition. Sixty three rabbit were divided into three groups: group 1 (n=18), group 2 (n=27) and group 3 (n=18). In group 1, 10 mm radius was defected, and one HA/TCP rod was implanted in the muscle a distant away from the bone defect area. In group 2, also, 10 mm radius was defected, one HA rod was implanted in the muscle a distant away from the bone defect area. In group 3, two HA/TCP rods were implanted in the dorsal muscle of the rabbit with bone intact. Histological observation showed that in group 1, some new bone was found only two months after implantation (n=2), and obvious immature woven bone could be observed in these bioceramics from the 3rd month on. However, in group 3, bone began to be found 6 months after implantation (n=2). In group 2, we could not find any bone tissue up to 9 month’s observation. These results suggest that, first, the bone defect model could significantly accelerate bone formation at non-osseous sites in rabbits; second,. HA/TCP bioceramics were confirmed with osteoinductive property while HA bioceramics without osteoinductive property nearly. Thus, bone defect might be a good animal model for further researches for osteoinductive bioceramics. 相似文献
964.
965.
红外与可见光复合寻的制导中的快速图像配准方法 总被引:3,自引:0,他引:3
对现有多传感器图像配准方法在红外与可见光复合寻的制导应用中存在的计算量大等不足,提出了一种基于部分Hausdorff距离的快速方法和一种两集合相似度的定义,从而实现了有效减小误匹配特征点对的红外与可见光图像快速配准方法.此算法通过分别提取两幅图像边缘上显著特征点,再根据提出的快速方法和两集合相似度定义,粗略估计出图像间的旋转角度、平移量;然后依据此估计值,缩小特征点匹配时匹配特征点搜索范围,求得一致特征点对;最后用最小二乘法求解最优变换参数.实验结果表明了该方法的有效性、快速性. 相似文献
966.
Liquid sloshing is a kind of very complicated free surface flow and exists widely in many fields. In order to calculate liquid
sloshing damping precisely a volume of fluid method based on finite volume scheme is used to simulate free surface flows in
partly filled cylindrical containers. A numerical method is presented to simulate the movement of the free surface flow, in
which a piecewise linear interface construction scheme and an unsplit Lagrangian advection scheme instead of Eulerian advection
scheme are used. The damping performance of liquid sloshing in cylindrical containers under fundamental sloshing mode is investigated.
There are four factors determining the surface-wave damping: free surface, boundary-layer, interior fluid and contact line.
In order to study different contributions from these four factors to whole damping, several examples are simulated. No-slip
and slip wall boundary conditions on both side wall and bottom wall of the cylindrical containers are studied to compare with
the published results obtained by solving Stokes equations. In the present method the first three main factors can be considered.
The simulation results show that the boundary-layer damping contribution increases while the interior fluid damping contribution
decreases with increase of Reynolds number.
Supported by the National Natural Science Foundation of China (Grant No. 10532010) 相似文献
967.
This paper introduces and analyses the renewal planning of “Zurich-West”, an old industrial area. It points out that systematic
and comprehensive target orientation, extensive collaboration in argumentation and decision-making, and the design ideas of
coexistence and integration are the key to its success. Considering the status quo of China’s old industrial district remodeling,
the paper offers some suggestions.
Supported by the National Natural Science Foundation of China (Grant No. 50878045) 相似文献
968.
Separation of nanocolloids driven by dielectrophoresis: A molecular dynamics simulation 总被引:1,自引:0,他引:1
The nonequilibrium molecular dynamics (MD) method was used to model the nanocolloids and the solvent particles. By introducing
a non-uniform electric field, colloids were polarized to have opposite polarities. Separation of colloids driven by dielectrophoresis
(DEP) could be seen clearly under a strong electric field at low temperatures. Analyzing the ratio of DEP velocities of colloids
to thermal velocities of neutral solvent particles showed that when the ratio was correspondingly big, collision between colloids
and solvent particles would be intense, making the DEP velocity of colloids fluctuate frequently. By changing the electric
field strength, it was found that the enhancement of electric field strength would quicken the separation of colloids. But
when the electric field strength increased to a certain degree, the separation motion would be slow because of the strong
friction resistance of the solvent particles to the colloids. Moreover, studying the separation reason of colloids based on
the potential energy showed that after colloids were polarized, the attractive potential energy among the colloids would be
weaker than before, while the increase of temperature would reduce the attractive potential energy and increase the repulsive
potential energy, which accorded with the DLVO theory.
Supported by the National Hi-Tech Research and Derelopment Program of China (“863” Project) (Grant No. 2006AA04Z351) and the
National Natural Science Foundation of China (Grant Nos. 50675033, 30770553) 相似文献
969.
Hao Wang GuiYu Yang YangWen Jia DaYong Qin Hong Gan JianHua Wang ChunMiao Han 《中国科学E辑(英文版)》2009,52(10):3004-3016
The necessity and feasibility of an ET-based modern water resources management was analyzed to improve assessment of critical water resources scarcity in the region/basin. This analysis was based on the whole water cycle process and its analysis object is evapotranspiration (ET), a main consumption component in the water resources dynamic transformation process. A case study was undertaken by selecting soil water resources in the Yellow River Basin and employing the WEP-L distributed hydrological model with... 相似文献
970.
在全球金融危机的背景之下, 信用担保机构的风险预警显得尤为重要.从信用担保机构的实际运营及管理机制出发, 系统地探索了风险的产生机理, 构建了基于GM(1, 1)的信用担保机构风险预警模型, 为担保机构有效进行风险防范提供参考. 相似文献