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RSA算法的内在特性、破解与防范措施

天津大学学报 2006年第B6期39卷 379-382页

作者：周绯菲鲁士文中国科学院研究生院

为了给RSA(Rivet、Shamir和Adelman提出的)算法的使用者提供参考,从不动点、周期性、对明文的要求、保密性和加密速度等方面分析了这种加密算法的内在特性,从理论和实际两方面对该算法的脆弱性以及针对该算法的攻击方法进行了分析。归... 详细信息

为了给RSA(Rivet、Shamir和Adelman提出的)算法的使用者提供参考,从不动点、周期性、对明文的要求、保密性和加密速度等方面分析了这种加密算法的内在特性,从理论和实际两方面对该算法的脆弱性以及针对该算法的攻击方法进行了分析。归纳出如何防范针对该算法攻击的结论,得出了RSA使用者使用的密钥匙位数必须大于2.48位才能保证算法安全性这一结果．通过给黑客的攻击方法进行分类,从算法维护和安全策略定制的角度,总结了网络安全人员提升加密算法安全性的办法．

关键词：加密算法解密破解

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论完全竞争理论的三大缺陷

四川大学学报（哲学社会科学版） 2004年第5期 16-20页

作者：吴练达王革王燕晓天津商学院学报编辑部天津300134 南开大学国际商学院天津300071 中国地质大学经管学院北京100081

完全竞争理论有三大缺陷 ,一是忽略了弱小者身陷完全竞争之中的事实 ,编造了资源最优配置的神话 ;二 ,它是一个静态理论 ,看不到完全竞争厂商试图摆脱完全竞争的处境所做的努力 ;三是未能从经济理性人出发推出价格是由完全竞争厂商决定... 详细信息

完全竞争理论有三大缺陷 ,一是忽略了弱小者身陷完全竞争之中的事实 ,编造了资源最优配置的神话 ;二 ,它是一个静态理论 ,看不到完全竞争厂商试图摆脱完全竞争的处境所做的努力 ;三是未能从经济理性人出发推出价格是由完全竞争厂商决定的 ,破坏了西方经济学的整体性。因此。

关键词：完全竞争价格控制价格形成经济理性人

Blockade of L-type calcium channel in myocardium and calcium-induced contractions of vascular smooth muscle by CPU 86017

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Acta Pharmacologica Sinica 2004年第4期 18-25页

作者： De-zai DAI2. Hui-juan HU3. JingZHAO, Xue-mei HAO4, Dong-mei YANG4, Pei-ai ZHOU4,Cai-hong WU4 Research Division of Pharmacology, china Pharmaceutical university, Nanjing, 2.0009 4National Laboratoryof Biomembrane and Membrane Biotechnology, Peking university, beijing 100871, china

AIM: To assess the blockade by CPU 86017 on the L-type calcium channels in the myocardium and on the Ca2.- related contractions of vascular smooth muscle. METHODS: The whole-cell patch-clamp was applied to investi- gate the blocking effect of CPU 86017 on the L-type calcium current in isolated guinea pig myocytes and contrac- tions by KCl or phenylephrine (Phe) of the isolated rat tail arteries were measured. RESULTS: Suppression of the L-type current of the isolated myocytes by CPU 86017 was moderate, in time- and concentration-dependent man- ner and with no influence on the activation and inactivation curves. The IC50was 11.5 μmol/L. Suppressive effect of CPU 86017 on vaso-contractions induced by KCl 100 mmol/L, phenylephrine 1 μmol/Lin KH solution (phase 1), Ca2. free KH solution ( phase 2. , and by addition of CaCl2.into Ca2.-free KH solution (phase 3. were observed. The IC50 to suppress vaso-contractions by calcium entry via the receptor operated channel (ROC) and voltage-depen- dent channel (VDC) was 0.3.0} μmol/L and 16.3.μmol/L, respectively. The relative potency of CPU 86017 to suppress vascular tone by Ca2. entry through ROC and VDC is 1/187 of prazosin and 1/3. of verapamil, respectively. CONCLUSION: The blocking effects of CPU 86017 on the L-type calcium channel of myocardium and vessel are moderate and non-selective. CPU 86017 is approximately 50 times more potent in inhibiting ROC than VDC.

关键词： chlorobenzyltetrahydroberine myocardium vascular smooth muscle patch-clamp techniques berberine calcium

On the dynamics in a transitional boundary layer

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Communications in Nonlinear Science and Numerical Simulation 2001年第3期6卷 111-171页

作者： C. B. LEE and R. LEE Department of Mechanics and Engineering Science/State Key Laboratory for Studies of Turbulence and Complex Systems, Peking university, beijing 100871,{2. Department of Engineering Mechanics, Tsinghua university, beijing 100084, Chi Department of Mechanics and Engineering Science / State Key Laboratory for Studies of Turbulence and Complex Systems Peking University Beijing 100871 China Department of Engineering Mechanics Tsinghua University Beijing 100084 China

A model is presented to describe the dynamic physical processes that occur in a transitional boundary layer flow. The CS-solitons, the closed vortex, the secondary closed vortex and the chain of ring-like vortices are postulated to be the basic flow structures of the transitional boundary layer as well as the turbulent boundary layer. It is argued that the central features of transitional and developed turbulent boundary layer flows can be explained in terms of how the series vortices interact with each other, and with the CS-solitons. The physical process that leads to the regeneration of the new closed vortex along the border of the CS-soliton, as well as the processes of evolution of the vortices to high frequency vortices, is described. The model is supported by the important developments in a number of "kernel" experiments, which illustrate both transitional and developed turbulent boundary layer. An important aspect of the model is that it has been formulated to be consistent with accepted rational mechanics concepts that are known to provide a proper physical description of other flows.

关键词： boundary layer transition dynamic processes onset of turbulence

Effects of temperature and irradiance on early development of Chondrus ocellatus Holm (Gigartinaceae,Rhodophyta)

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Chinese Journal of Oceanology and Limnology 2010年第3期28卷 508-513页

作者：李晓赵鹏王高歌李大鹏王继成段德麟 Institute of Oceanology Chinese Academy of Sciences graduate School of Chinese Academy of Sciences Ocean university of china

Chondrus is a type of commercially produced red seaweed that widely used for food and carrageen extraction. Although the natural life history of the alga had been well understood, the factors influencing development of the tetraspore and carpospore remain poorly understood. In the perspective of seedling resources, the regulation of early development is crucial for the seedlillg nursing; therefore, it is necessary to understand the physiological influences during its early development. In this study, we studied the effects of temperature and irradiance on the early development of Chondrus ocellatus Holm under laboratory conditions. The released tetraspores and carpospores were cultivated at different temperatures （10-2.℃） and irradiances （10, 60 μmol photons m^-2.^-1） with a photoperiod of 12.： 12.. The results indicate that both tetraspores and carpospores are tolerant to temperatures of 10-2.℃, and have the highest relative growth rate at 2.℃. Irradiance variances influenced the growth of the discoid crusts, and the influence was more significant with increasing temperature; 60 μmol photons m^-2.^-1 was more suitable than 10 μmol photons m^-2.^-1. The optimum temperature and irradiance for the development of seedlings was 2.℃ and 60 μmol photons m^-2.^-1, respectively.

关键词： Chondrus ocellatus temperature irradiance early development

Design and Simulation of FIR Filter Based on VHDL

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Design and Simulation of FIR Filter Based on VHDL

Thrombin-like enzymes from venom gland of Deinagkistrodon acutus:cDNA cloning,mechanism of diversity and phylogenetic tree construc-tion

第14届中国系统仿真技术及其应用学术年会

作者： Huaiwei LIN 1,Min FEI 2.Wei XING 3.1 Faculty of Engineering,Jiangxi Agricultural university,Jiangxi,china 2.{2. Institute of Radio Metrology &Measurement,{2.,china 3.{2. Research Institute,ZTE Corporation,{2.,china

According to the principle and characteristic of FIR low pass filter,through using MATLAB software to simulate frequency response of some performance index and tap coefficients about FIR filter,This paper gives an example to design and simulate FIR low pass filter,which has anti-aliasing function for CD players in VHDL language,It can be realized the filter’s action and function with software describing hardware.

关键词： FIR filter simulation VHDL MATLAB

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Acta Pharmacologica Sinica 2006年第2期27卷 184-192页

作者： Xiang-dong ZHA~(2.3.7) He-sheng HUANG~(4,7) Li-zhi ZHOU~(2.3. Jing LIU~5 Kang-sen XU~6 ~2.chool of Life Sciences,Anhui {3.,Hefei 2.003.,china ~3.nhui Key Laboratory of Eco-Engineering and Bio-techniques,Hefei 2.003.,china ~4Department of Pharmacology,Anhui Medical {3..Hefei 2.002.,china ~5School of Life Sciences,{3. of Science and Technology of{13.,Hefei 2.002.,china ~6Institute for Control of Pharmaceuticals and Biological Products,beijing 100050,china SchoolofLifeSciences AnhuiUniversityHefei230039China AnhuiKeyLaboratoryofEco-EngineeringandBio-techniques Hefei230039China DepartmentofPharmacology AnhuiMedicalUniversityHefei230022China

Aim:To clone cDNAs of thrombin-like enzymes(TLEs)from venom gland ofDeinagkistrodon acutus and analyze the mechanisms by which their structuraldiversity ***:Reverse transcription-polymerase chain reaction andgene cloning techniques were used,and the cloned sequences were analyzed byusing bioinformatics ***:Novel cDNAs of snake venom TLEs *** possibilities of post-transcriptional recombination and horizontalgene transfer are discussed.A phylogenetic tree was ***:The cDNAs of snake venom TLEs exhibit great *** are severaltypes of structural *** variations may be attributable to certainmechanisms including recombination.

关键词： thrombin-like enzymes structural diversity RNA recombination phylogenetic tree

Spectral　Characteristics　of　Atmospheric　Turbulence　Model

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Communications in Nonlinear Science and Numerical Simulation 1996年第4期1卷 25-28页

作者： Guojun XIN Shida LIU Shikou LIU & Fuming LIANG (Dept. of Geophysics, Peking university, beijing, 100871, P.R.{2.) Dept. of Geophysics Peking University Beijing 100871 P.R.China

ＳｐｅｃｔｒａｌＣｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆＡｔｍｏｓｐｈｅｒｉｃＴｕｒｂｕｌｅｎｃｅＭｏｄｅｌ１１ＴｈｅｐａｐｅｒｗａｓｒｅｃｅｉｖｅｄｏｎＯｃｔ．２５，１９９６ＧｕｏｊｕｎＸＩＮＳｈｉｄａＬＩＵＳｈｉｋｏｕ... 详细信息

ＳｐｅｃｔｒａｌＣｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆＡｔｍｏｓｐｈｅｒｉｃＴｕｒｂｕｌｅｎｃｅＭｏｄｅｌ１１ＴｈｅｐａｐｅｒｗａｓｒｅｃｅｉｖｅｄｏｎＯｃｔ．２５，１９９６ＧｕｏｊｕｎＸＩＮＳｈｉｄａＬＩＵＳｈｉｋｏｕＬＩＵ＆ＦｕｍｉｎｇＬＩＡＮＧ（Ｄ...

关键词： KdV-Burgers equation heteroclinic orbit turbulent spectrum

Regression Analysis on the Causes of the International Gold Prices Rising

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Regression Analysis on the Causes of the International Gold ...