检索结果-南通市图书馆

对8轮mCrypton-96的中间相遇攻击

在线全文

学校读者我要写书评

暂无评论

计算机研究与发展 2016年第3期53卷 666-673页

作者：王高丽甘楠华东师范大学计算机科学与软件工程学院上海200062 东华大学计算机科学与技术学院上海201620

在分析分组密码算法的安全性时,利用密钥关系来降低时间、存储和数据复杂度是一个常用的手段.在4轮mCrypton-96性质的基础上,利用密钥生成算法的弱点和S盒的性质,降低了攻击过程中需要猜测的密钥比特数,提出了对8轮mCrypton-96算法的中... 详细信息

在分析分组密码算法的安全性时,利用密钥关系来降低时间、存储和数据复杂度是一个常用的手段.在4轮mCrypton-96性质的基础上,利用密钥生成算法的弱点和S盒的性质,降低了攻击过程中需要猜测的密钥比特数,提出了对8轮mCrypton-96算法的中间相遇攻击,攻击的时间复杂度约为2^(93.5)次8轮mCrypton-96加密运算,存储复杂度为2^(47)B,数据复杂度为2^(57)个选择明文.

关键词：密码算法分析中间相遇攻击分组密码 mCrypton 密钥关系

Comparison of extracorporeal and conventional cardiopulmonary resuscitation:A meta-analysis of 2 260 patients with cardiac arrest

在线全文

学校读者我要写书评

暂无评论

World Journal of Emergency Medicine 2017年第1期8卷 5-11页

作者： gan-nan Wang Xu-feng Chen Li Qiao Yong Mei Jin-ru Lv Xi-hua Huang Bin Shen Jin-song Zhang Department of Emergency Medicine the First Affiliated Hospital of Nanjing Medical University NanjingChina

BACKGROUND: This meta-analysis aimed to determine whether extracorporeal cardiopulmonary resuscitation(ECPR), compared with conventional cardiopulmonary resuscitation(CCPR), improves outcomes in adult patients with cardiac arrest(CA).DATA RESOURCES: Pub Med, EMBASE, Web of Science, and China Biological Medicine Database were searched for relevant articles. The baseline information and outcome data(survival, good neurological outcome at discharge, at 3–6 months, and at 1 year after CA) were collected and extracted by two authors. Pooled risk ratios(RRs) and 95% confidence intervals(CIs) were calculated using Review Manager ***: In six studies 2 260 patients were enrolled to study the survival rate to discharge and longterm neurological outcome published since 2000. A signi? cant effect of ECPR was observed on survival rate to discharge compared to CCPR in CA patients(RR 2.37, 95%CI 1.63–3.45, P<0.001), and patients who underwent ECPR had a better long-term neurological outcome than those who received CCPR(RR 2.79, 95%CI 1.96–3.97, P<0.001). In subgroup analysis, there was a significant difference in survival to discharge favoring ECPR over CCPR group in OHCA patients(RR 2.69, 95%CI 1.48–4.91, P=0.001). However, no signi? cant difference was found in IHCA patients(RR 1.84, 95%CI 0.91–3.73, P=0.09).CONCLUSION: ECPR showed a bene? cial effect on survival rate to discharge and long-term neurological outcome over CCPR in adult patients with CA.

关键词： Extracorporeal cardiopulmonary resuscitation Cardiac arrest Adult Outcome Meta-analysis

Analysis of signal-obtaining error factor of sensor in gyro

在线全文

学校读者我要写书评

暂无评论

Journal of Marine Science and Application 2005年第2期4卷 28-33页

作者： LIU Jian-feng YUAN gan-nan ZHAO Shi-jun School of Automation Harbin Engineering University Harbin 150001 China

The digital signal-obtaining for gyroscope is given. The single optic-fiber sensor via modulating intensity of light is used as measuring eonlponent . The influence on static transmission properties resulting from the special working environnlent （e. g. cryogenic and vacuum） ,the measure error because of tile reflector shape of rotor,the abnormity of facula from sensor caused by the existence of engraving error,and tile fixing error of sensor and the error of machine tool＇s initial lignnlent are investigated. The mathematic model in every condition is founded, the simulation and relative experiments ale done and the outeome is analyzed. The mathematic model and method of compensating technology are studied and some relative experiments are made. The result of study is usefid to improvement of the signal-obtaining system.

关键词： fiber-optic sensor signal-obtaining for gyrn cryogenic and vacuum measure error

Analysis of deformation of rotor and influence on the performance of Gyro based on B-Spline wavelet FEM

在线全文

学校读者我要写书评

暂无评论

Journal of Marine Science and Application 2005年第4期4卷 12-17页

作者： LIU Jian-feng YUAN gan-nan ZHOU Wei-dong School of Automation Harbin Engineering University Harbin 150001 China

Some construct characteristics and composing material of the new Gyro＇ s rotor are introduced. Some factors resulting in deformation of the rotor surface are analyzed. Under different loads such as the fo,＇ce of deflecting center, the change of temperature, the fo,ce of pressure and couple factors, the deformation of rotor is analyzed with the wavelet finite element simulation software. The vector distributing map of rotor reformation is given. The deformation resulting from the pressure force of photon is studied. Finally, the influence on Gyro＇ s performance because of anomalous surface of rotor due to deformation of rotor is researched and the result is useful to forecast the performance of the drift of gyroscope. The disturbing moment resulting from the deformation of rotor can be compensated using the mathematic method, and provides an important reference for both design and optimization of the rotor.

关键词： the rotor of new Gyro the deformation of rotor the wavelet finite element the drift of Gyro

RF design and test of a high-directivity high-power waveguide directional coupler for the HEPS

在线全文

学校读者我要写书评

暂无评论

Radiation Detection Technology and Methods 2022年第2期6卷 137-142页

作者： Xiang He Jing-Ru Zhang Jing-Dong Liu Hua Shi Bing-Lin Deng Xu-Jian Wang Sheng-Chang Wang nan gan Pi-Long Tian Key Laboratory of Particle Acceleration Physics and Technology Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China

Purpose A novel high-directivity high-power waveguide directional coupler(DC)working at 2998.8 MHz is developed for the High Energy Photon *** can help the phase control system to obtain a very accurate microwave signal,which is very important to minimize the beam *** The novel reversely placed T-type coupling piece helps to obtain a high *** N-type high-vacuum feedthroughs for vacuum sealing instead of the traditional ceramic plate is beneficial to holding a higher peak *** simulation and the high-power commissioning are accomplished in the Institute of High Energy Physics(IHEP),while the fabrication and the low-power test are conducted in cooperation with the *** Both the single-coupler and the dual-coupler DCs are developed with a directivity of more than 35 dB while keeping the coupling factor within 60±0.5 ***,69.4%of all the fifty-two mass produced DCs have got a directivity of more than 40 ***:The mature manufacturing process for mass production is *** novel high-directivity high-power waveguide DC can be mass produced with an actually internationally leading performance.

关键词： HEPS Directional coupler High directivity High power Mass production

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

T应力对混凝土断裂参数测定有效性的影响

大连理工大学学报 2013年第4期53卷 537-542页

作者：赵艳华甘楠楠大连理工大学土木工程学院辽宁大连116024

对于线弹性材料,裂缝尖端平行于裂缝方向的T应力会影响裂缝的扩展方向和起裂断裂韧度,然而在混凝土类准脆性材料的断裂韧度测试中,无论是起裂断裂韧度还是失稳断裂韧度,T应力的影响却少有研究.以混凝土Ⅰ型断裂韧度测试常用的三点弯曲... 详细信息

对于线弹性材料,裂缝尖端平行于裂缝方向的T应力会影响裂缝的扩展方向和起裂断裂韧度,然而在混凝土类准脆性材料的断裂韧度测试中,无论是起裂断裂韧度还是失稳断裂韧度,T应力的影响却少有研究.以混凝土Ⅰ型断裂韧度测试常用的三点弯曲梁、楔入劈拉试件为对象,计算了裂缝尖端的T应力大小,并分析了其对裂缝扩展方向和断裂韧度的影响.分析计算结果表明:这些常用试件裂缝尖端的T应力相比于裂缝尖端控制因素应力强度因子K很小,不会影响裂缝扩展方向,保证了混凝土断裂失稳前一直处于Ⅰ型裂缝状态;另外,T应力对起裂断裂韧度和失稳断裂韧度的数值也不会产生影响,说明常用试件进行的混凝土断裂韧度确定方法是可靠有效的.

关键词：混凝土断裂力学断裂韧度 T应力

Analysis of a Gyroscope′s Rotor Nonlinear Supported Magnetic Field Based on the B-Spline Wavelet-FEM

在线全文

学校读者我要写书评

暂无评论

International Journal of Plant Engineering and Management 2005年第3期10卷 152-159页

作者： LIU Jian-feng YUAN gan-nan HUANG Xu YU Li College of Automation Harbin Engineering University Harbin 150001 P. R. China College of Communication Jiamusi University Jiamusi 154002 P. R. China

A supported framework of a gyroscope＇s rotor is designed and the B-Spline wavelet finite element model of nonlinear supported magnetic field is worked out. A new finite element space is studied in which the scaling function of the B-spline wavelet is considered as the shape function of a tetrahedton. The magnetic field is spited by an artificial absorbing body which used the condition of field radiating, so the solution is unique. The resolution is improved via the varying gradient of the B-spline function under the condition of unchanging gridding. So there are some advantages in dealing with the focus flux and a high varying gradient result from a nonlinear magnetic field. The result is more practical. Plots of flux and in the space is studied via simulating the supported system model. The results of the study are useful in the research of the supported magnetic system for the gyroscope rotor.

关键词： nonlinear supported magnetic field B-spline wavelet FEM gyroscope interpolation basis function boundary condition

在线全文

学校读者我要写书评

暂无评论

玛依纳水电站水力过渡过程数值计算分析

水力发电 2016年第11期42卷 88-90页

作者：甘楠中国电建集团成都勘测设计研究院有限公司四川成都610072

玛依纳水电站引水发电系统无法满足GB/T9652.1—2007《水轮机控制系统技术条件》要求,系统稳定性较差。为此,在引水发电系统枢纽布置无法改变的情况下,在牺牲调速系统速动性,放宽对电站调节品质要求的前提下讨论其引水发电系统布置的可... 详细信息

玛依纳水电站引水发电系统无法满足GB/T9652.1—2007《水轮机控制系统技术条件》要求,系统稳定性较差。为此,在引水发电系统枢纽布置无法改变的情况下,在牺牲调速系统速动性,放宽对电站调节品质要求的前提下讨论其引水发电系统布置的可行性。目前,2台机组已经安全稳定运行多年,证明该电站引水发电系统布置是合理的。

关键词：引水发电系统水力过渡过程水流惯性时间常数机组惯性时间常数玛依纳水电站

在线全文

学校读者我要写书评

暂无评论

基于MIMU/GPS的组合导航设计及实验

光学精密工程 2008年第2期16卷 285-294页

作者：杨金显袁赣南哈尔滨工程大学自动化学院黑龙江哈尔滨150001

根据航弹和MEMS技术特点设计了基于MIMU/GPS的组合导航系统。MIMU采用模块化设计,提高了可靠性;参考JDAM的性能指标,计算各模块指标;采用一种双频圆极化微带天线改善天线的宽带宽角特性,提高了GPS接收机灵敏度;借助GPS广域差分增强系统... 详细信息

根据航弹和MEMS技术特点设计了基于MIMU/GPS的组合导航系统。MIMU采用模块化设计,提高了可靠性;参考JDAM的性能指标,计算各模块指标;采用一种双频圆极化微带天线改善天线的宽带宽角特性,提高了GPS接收机灵敏度;借助GPS广域差分增强系统得到精密GPS星历和广域差分电离层网格改正数,有效解算定位精度提高了10倍以上。根据需求,合理简化组合导航数学模型并采用改进的模糊自适应Kalman滤波,仿真和实验表明,该设计满足制导精度在5 m以内的要求;并可在国产导航系统成熟的条件下,实现平稳过渡。

关键词：航弹 MIMU/GPS 组合导航系统改进的Kalman滤波