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91.
黄甜 《科技情报开发与经济》2011,21(2):223-224
既有建筑节能改造是当前我国建筑节能工作的重点,但由于材料、施工、法规监管等多方面的原因,给我国建筑防火安全造成了许多重大隐患和事故。就如何在建筑节能改造中通过多种手段处理好防火安全问题进行了讨论,提出一些可供借鉴的方法。 相似文献
92.
We study on the implementation flow of the radio computerized tomography (RCT) prediction method. A case in real cellular
mobile radio (CMR) system together with the prediction results are also presented. As shown by the results, the RCT prediction
method is marked for its convenience and rapidity, as well as its relative high precision even when the prediction procedure
is highly simplified. Since it is developed according to the characteristics of wireless communication environments of our
country and has concurrently merits from both statistical and deterministic prediction models, the RCT prediction method is
in good agreement with engineering practices in cellular mobile communication in cities at home. Optimized by combining with
other techniques, further improvement could be achieved in the stability and precision of the RCT prediction method which
now serves as the core part of a software tool for commercial use in CMR system analysis and optimization.
Biography: Yu Sheng-bing (1974-), male, Ph. D candidate, research interest: theory analysis and application development of
radio propagation in wireless communication systems. 相似文献
93.
如何在大学历史教学中贯穿真善美教育 总被引:1,自引:0,他引:1
胡克森 《邵阳高等专科学校学报》2011,(5):101-104
在当今的社会转型时期,整个社会需要重建道德价值和精神价值。因此,对大学生进行真善美的知识教育十分必要,而进行真善美综合知识教育,历史学是最适合的。在历史教学中对大学生进行"真""善""美"的知识教育,第一是利用历史学的科学功能对学生进行求真的教育,然后要利用历史学的教育功能和艺术功能对学生进行"为善"的教育和审美的教育,告诉他们以历史上的道德楷模和英雄人物为榜样,树立起美好的人生理想,培养好的道德操守,从而改变社会风气,重建民族精神风貌。 相似文献
94.
As a requisite and key step in some gradient-based measurement techniques, the reconstruction of the shape, more generally the scalar potential, from the measured gradient data has been studied for many years. In this work, three types of two-dimensional integration methods are compared under various conditions. The merits and drawbacks of each integration method are consequently revealed to provide suggestions in selection of a proper integration method for a particular application. 相似文献
95.
A vertex-deleted subgraph of a graph G is a card. A dacard specifies the degree of the deleted vertex along with the card. The adversary degree-associated reconstruction number is the least k such that every set of k dacards determines G. We determine , where the double-broom with is the tree with vertices obtained from a path with p vertices by appending m leaves at one end and n leaves at the other end. We determine for all . For , usually , except and . There are exceptions when or . For the usual value is 4, with exceptions when or . 相似文献
96.
97.
针对当前关于数据流加权最大频繁项集WMFI(weighted maximal frequent itemsets)的研究无法有效地处理频繁阈值和加权频繁阈值不一致情况下WMFI的挖掘问题,提出了完全加权最大频繁项集FWM FI(full w eighted maximal frequent itemsets)的概念.为了减少naive算法在处理滑动窗口下完全加权最大频繁项集挖掘时存在的冗余运算,提出了FWMFI-SW(FWMFI mining based on sliding window over data stream)算法.所提出的算法通过基于频繁约束条件的优化策略减少了naive算法中M ax W优化策略的无效调用次数;采用编辑距离比率作为WMFP-SW-tree的重构判别函数,可以有效减少该树的重构次数.实验结果表明FWMFI-SW算法是有效的,且比naive算法更有时间优势. 相似文献
98.
History has shown that it is not as easy as one might think to differentiate between bulk nanobubbles and nanodroplets or nanoparticles. It is generally easy to detect colloids (i.e. something that looks different, e.g. scatters light differently than its surrounding solvent), but less easy to determine the nature of these colloids. This has led to misinterpretations in the literature, where nanodroplets or nanoparticles have mistakenly been assumed to be nanobubbles. In this paper, we review a multitude of experimental methods and approaches to prove the existence of bulk nanobubbles. We conclude that combinations of optical detection with physical perturbations such as pressure or ultrasound, or phase-sensitive holographic methods are the most promising and convenient approaches. 相似文献
99.
The development of the anti-malaria vaccine holds a promising future in malaria control. One of the anti-malaria vaccine strategies known as the transmission-blocking vaccine (TBV) is to inhibit the parasite transmission between humans and mosquitoes by targeting the parasite gametocyte. Previously, we found that P48/45 included in the 6-Cysteine protein family shared by Plasmodium sp. We also detected vaccine properties possessed by all human-infecting Plasmodium and could be used as a cross-species anti-malaria vaccine. In this study, we investigated the efficacy of P48/45 through the ancestral and consensus reconstruction approach. P48/45 phylogenetic and time tree analysis was done by RAXML and BEAST2. GRASP server and Ugene software were used to reconstruct ancestral and consensus sequences, respectively. The protein structural prediction was made by using a psipred and Rosetta program. Each protein characteristic of P48/45 was analyzed by assessing hydrophobicity and Post-Translational Modification sites. Meanwhile, the Epitope sequence for B-cell, T-cell, and HLA was determined using an immunoinformatics approach. Lastly, molecular docking simulation was done to determine native binding interactions of P48/45-P230. The result showed a distinct protein characteristic of ancestral and consensus sequences. The immunogenicity analysis revealed the number of epitopes in the ancestral sequence is greater than the consensus sequence. The study also found a conserved epitope located in the binding site and consists of specific Post-Translational Modification sites. Hence, our research provides detailed insight into ancestral and consensus P48/45 efficacy for the cross-species anti-malaria vaccine. 相似文献
100.
Kubat JA Chou JJ Rovnyak D 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2007,186(2):201-211
Residual dipolar couplings (RDC) provide important global restraints for accurate structure determination by NMR. We show that nonuniform sampling in combination with maximum entropy reconstruction (MaxEnt) is a promising strategy for accelerating and potentially enhancing the acquisition of RDC spectra. Using MaxEnt-processed spectra of nonuniformly sampled data sets that are reduced up to one fifth relative to uniform sampling, accurate 13C'-13Calpha RDCs can be obtained that agree with an RMS of 0.67 Hz with those derived from uniformly sampled, Fourier transformed spectra. While confirming that frequency errors in MaxEnt spectra are very slight, an unexpected class of systematic errors was found to occur in the 6th significant figure of 13C' chemical shifts of doublets obtained by MaxEnt reconstruction. We show that this error stems from slight line shape perturbations and predict it should be encountered in other nonlinear spectral estimation algorithms. In the case of MaxEnt reconstruction, the error can easily be rendered systematic by straightforward optimization of MaxEnt reconstruction parameters and self-cancels in obtaining RDCs from nonuniformly sampled, MaxEnt reconstructed spectra. 相似文献