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941.
设图H是图G的一个子图,一个H匹配是与H同构的点不相交的子图集合,将图G中H的匹配数记为v(H,G)。本文用交错不等式来研究v(H,G)与图G的标准化拉普拉斯谱之间的一些关系。 相似文献
942.
<正> Security assessment can help understand the security conditions of an information system and yieldresults highly conducive to the solution of security problems in it.Taking the computer networks in a certainuniversity as samples,this paper,with the information system security assessment model as its foundation,proposes a multi-attribute group decision-making (MAGDM) security assessment method based ona variable consistency dominance-based rough set approach (VC-DRSA).This assessment method combinesVC-DRSA with the analytic hierarchy process (AHP),uncovers the inherent information hidden indata via the quality of sorting (QoS),and makes a synthetic security assessment of the information systemafter determining the security attribute weight.The sample findings show that this methoil can effectivelyremove the bottleneck of MAGDM,thus assuming practical significance in information system security assessment. 相似文献
943.
In order to improve removal for nitrogen in a pilot-scale submerged membrane bioreactor (SMBR), intermittent aeration was
conducted, and the effect on the treatment performance under four kinds of operation condition (run 1, continuous aeration;
run 2, 60/60 min aeration on/off time; run 3, 60/90 min aeration on/off time; run 4, 60/75 min aeration on/off time) was evaluated.
The results showed that depending on the specific on/off of the aeration time ratio, removal efficiency of nitrogen could
be improved significantly, and the removal rates of total nitrogen (TN) under different operation conditions were 28.0%, 59.5%,
66.8% and 70.7%, respectively. There were no obvious differences for removal rates for CODCr and ammonia among different operation conditions. In general, intermittent aeration could be used as a feasible way to improve
treatment performance for nitrogen in the SMBR. 相似文献
944.
李梁 《科技情报开发与经济》2010,20(26):182-183,201
在分析高层住宅楼外居住条件影响因素的基础上,提出了用建筑手段改进高层住宅楼外部居住条件的设想。 相似文献
945.
缺乏必要的语言学习环境,导致教学效率不高,这个问题多年来困扰着外语教学工作者。为此,提出一种低成本、高效率的解决方案,用以研发英语学习系统,引导英语教学体系改革,即借助人工智能(AI)和计算机网络技术,模拟实际生活,构建共享的多媒体语言教学环境。论证并设计了一种创新的智能英语学习系统(IELS),提出了系统目标,并就功能实现做出了详细的规划。 相似文献
946.
介绍了某变电站的基本情况,针对一起故障的发生进行了现场检查,找出造成该故障的根本原因,制定了处理方案。 相似文献
947.
The shock compression experiment of liquid helium is an available way to gain properties of specimen at high temperatures and pressures.Based on Fluent,a thermal insulation analysis and design of a liquid helium temperature target in the environment condition of 100 Pa for shock compression experiment is performed.Then,a cryogenic target with a 10 K helium vapor shield and a separated vacuum interval is particularly developed.A lowest temperature of 3.63 K and a stable temperature of 3.70 K in the specimen cavity with an accuracy of 0.1 K are obtained by means of continuous flow and vacuum cooling.Both time-consuming and temperature stability are well-suited to the requirements of the shock compression experiment.The results show that the calculated and experimental data well-matched each other.The simulation method may be effective and feasible for the optimal design of the cryogenic target. 相似文献
948.
双参数Co半群的收敛性问题 总被引:1,自引:0,他引:1
本文给出了有关双参数C0半群的一些性质,研究了双参数C0半群收敛性问题,借助单参数C0半群与双参数C0半群之间的关系,在一定条件下,将单参数C0半群序列的收敛性推广到了双参数C0半群上. 相似文献
949.
中原民间传统体育开展现状及对策 总被引:1,自引:0,他引:1
郭亮 《河南教育学院学报(自然科学版)》2012,21(1)
通过对中原地区民间传统体育的了解和中原民间传统体育开展现状的调查研究,指出民间传统体育在发展中存在的一些问题,提出相应的解决方法. 相似文献
950.
Langevin equation is widely used to study the stochastic effects in molecular networks, as it often approximates well the
underlying chemical master equation. However, frequently it is not clear when such an approximation is applicable and when
it breaks down. This paper studies the simple Schnakenberg model consisting of three reversible reactions and two molecular
species whose concentrations vary. To reduce the residual errors from the conventional formulation of the Langevin equation,
the authors propose to explicitly model the effective coupling between macroscopic concentrations of different molecular species.
The results show that this formulation is effective in correcting residual errors from the original uncoupled Langevin equation
and can approximate the underlying chemical master equation very accurately. 相似文献