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991.
本文针对主流楼控技术的网络架构、协议及某网站实验室的国内外楼控系统的排名进行了相应的分析研究,并重点比较了国内外典型楼控系统的各项数据,为楼控的产品选型提供了有力依据。 相似文献
992.
993.
Yu-liang Shi Yu Chen Zhong-min Zhou Li-zhen Cui 《Journal of Signal Processing Systems》2017,89(1):27-39
Nowadays big data security plays a major issue in cloud computing. Chunk-confusion-based privacy protection mechanism (CCPPM) protects the privacy of the tenants in plaintext. But both multi-tenant applications’ data and tenants’ privacy requirements are dynamically changing, which will have a great effect on the underlying storage model of cloud data. Moreover, the tenants’ business processing will change the data distribution and destroy the distribution balance of privacy data, which makes the data stored in the cloud face the risk of leakage of privacy. Therefore, the paper proposed a privacy protection evaluation mechanism for dynamic data based on CCPPM. The paper firstly introduces three kinds of the privacy leakages due to unbalanced data under the CCPPM, and analyzes two methods used for attacking. Aiming at the privacy leakages and the attack methods, we proposed a dynamic data processing algorithm to record the tenants’ operation sequence and set up the corresponding evaluation formula. Next, we evaluated the effect of privacy protection from two aspects of simple attack and background-knowledge-based attack, and used the data distribution similarity privacy preserving dynamic evaluation algorithm presented in this paper to obtain the measurement results of privacy leakages. Finally, according to the evaluation results, the defense strategies are given to prevent data privacy leakages. The experimental evaluation proves that rationality of dynamic the evaluation mechanism proposed in this paper has better feasibility and practicality for big data privacy protection. 相似文献
994.
Ximing Sun Yujie Dong Zhengcao Li Lei Shi Yuliang Sun 《Journal of Nuclear Science and Technology》2017,54(2):196-204
The oxidation behavior of a selected nuclear graphite (IG-110) used in Pebble-bed Module High Temperature gas-cooled Reactor was investigated under the condition of air ingress accident. The oblate rectangular specimen was oxidized by oxidant gas with oxygen mole fraction of 20% and flow rates of 125–500 ml/min at temperature of 400–1200?°C. Experiment results indicate that the oxidation behavior can also be classified into three regimes according to temperature. The regime I at 400–550?°C has lower apparent activation energies of 75.57–138.59 kJ/mol when the gas flow rate is 125–500 ml/min. In the regime II at 600–900?°C, the oxidation rate restricted by the oxygen supply to graphite is almost stable with the increase of temperature. In the regime III above 900?°C, the oxidation rate increases obviously with the increase of temperature. With the increase of inlet gas flow from 125 to 500 ml/min, the apparent activation energy in regime I is increased and the stableness of oxidation rate in regime II is reduced. 相似文献
995.
In Jiang (1988), a condition is given which is supposedly necessary and sufficient for the stability of interval matrices in discrete-time systems. We demonstrate, via a counter-example, that the condition given is, in fact, not sufficient. 相似文献
996.
The influence of explosive charge thickness on the quality of explosive welding of dissimilar metals was in-vestigated.The lower limit law should be followed in the course of explosive welding.Three welding ex-periments of stainless steel (410S) and steel (Q345R) were carried out in three different kinds of explo-sive charge thicknesses, namely 15, 25 and 35 mm.Interfaces of morphology and mechanical properties of three samples were observed and tested.It was found that micro and small wavy bonding is mainly formed for charge thickness of 15 mm whose strength is the highest with minor deformation and few defects in the interface; small and middle wavy bonding are mainly formed for charge thickness of 25 mm whose strength is comparatively mediocre; big wavy bonding is mainly formed for charge thickness of 35 mm whose strength is the lowest.The cause of high bonding strength of the micro and small wavy interface was analyzed and verified on the basis of the results of Electron Probe Micro-Analyzer (EPMA) tests of three selected samples. 相似文献
997.
998.
In this paper, we formulate an interesting problem of multicriteria decision-making task ranking in social networks (MCDM-TR). MCDM-TR contains two phases: (1) finding a set of decision-making experts for tasks who not only complete the decision-making of the given task but also have the minimal communication cost among them; (2) ranking the decision-made tasks according to a certain decision standard. In this paper, we focus on these two phases and propose an efficient algorithm for multicriteria decision-making tasks in social networks. A case study of academic conferences quality evaluation system (ACQES) is also studied to illustrate our strategy. 相似文献
999.
GAO Shi MA Qingjie CUI Qu LIU Lin ZHOU Xueyan JIA Bing CHEN Zuowei ZHANG Haishan 《核技术(英文版)》2013,(2):36-40
The 99mTc-3PRGD2 targeted SPECT/CT scanning was of significance in detecting differentiated glioma.In this work,the diagnostic value of 99mTc-3PRGD2 scintigraphy in brain glioma was evaluated by the ten clinically verified brain glioma patients after obtaining informed consent.The patients first accepted X-ray imaging to localize the detecting regions before administrating with 99mTc-3PRGD2 at a mean radioactivity of 849±115 MBq via single intravenous bolus injection 2 h prior to SPECT/CT imaging.Tumor samples for detectingαvβ3 were collected by surgical operations two weeks after the scintigraphy.The results of CT and SPECT scanning were merged and compared.The correlation between tumor occupation(T/N ratio) andαvβ3 expression level were analyzed.The T/N ratios in brain glioma were proportionally correlated to av(33 positive cell percentage(R2=0.9253,p<0.05).This study primarily evaluated the clinical application of 99mTc-3PRGD2 SPECT scintigraphy on brain glioma.The more pathological types and detecting strategies covering a large amount of samples would aid to clarify the potentials. 相似文献
1000.
Abstract Among the parameters that affect photolithography, the most important are exposure and development time which affect the coating photoresist characteristics. This study further researches the relationship between the exposure and development time using a high speed image inspection system, and the relationship between the development time and photoresist depth using a Scanning Probe Microscope (SPM). A partial scan CCD camera and high speed frame capture card were used to obtain the photoresist development processing parameters. The experimental results verified that this imaging system provides an economical and effective method for producing a micro‐photo‐etched product. It is expected that these experiments can also offer some good references useful in the micro electro mechanical industrial field. 相似文献