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无线电传播简介:专用术语,室内传播和路径损耗计算及实例

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今日电子 2002年第Z1期 26-30页

作者： adi shamir RFWaves公司

通过对传播路径损耗的估算来预测无线通信系统在其工作环境下的性能;解释了自由空间传播损耗的计算;电磁波在介质中的发射和反射系数的理论计算是预测反射和发射系数的工具.下面的一些实例和模型是在2.4GHz工作频率时给出的.

关键词：无线电传播术语室内传播路径损耗损耗计算无线通信系统自由空间在介质中预测理论计算工作频率工作环境反射系数发射系数传播损耗电磁波性能模型解释估算

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维普期刊数据库

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DES型密码体制的差分密码分析

遥测遥控 1991年第5期12卷 59-65,58页

作者： Eli Biham adi shamir 吴兴龙

数据加密标准(DES)是一种众知的密码体制,它是七十年代中期IBM公司研制并为美国国家标准局承认的。它已成功地抵御了迄今为止有关文献公开发表的所有攻击。本文提出新的密码分析攻击,只要在PC机上进行数分钟运算,就能破译多达8圈的DES... 详细信息

数据加密标准(DES)是一种众知的密码体制,它是七十年代中期IBM公司研制并为美国国家标准局承认的。它已成功地抵御了迄今为止有关文献公开发表的所有攻击。本文提出新的密码分析攻击,只要在PC机上进行数分钟运算,就能破译多达8圈的DES。此外,破译多达15圈的DES,其速度也比穷举搜索方法快得多。这种新的攻击可用于各种DES型的代替/置换密码体制,并证明(未公开发表的)设计准则的关键性作用。

关键词：数据加密标准差分码分析密钥

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对DES类密码体制的差分密码分析

信息安全与通信保密 1991年第3期13卷 59-67页

作者： Eli Biham adi shamir 罗昭武

在民用场合,数据加密标准(DES)是最为有名的密码体制,而且己经被人们广泛使用。在七十年代中期,DES由IBM公司提出,并被美国国家标准局采用。从公开的文献看,到目前为止,DES已经成功地经受住了各种已发表的密码攻击。本文提出一种新的密... 详细信息

在民用场合,数据加密标准(DES)是最为有名的密码体制,而且己经被人们广泛使用。在七十年代中期,DES由IBM公司提出,并被美国国家标准局采用。从公开的文献看,到目前为止,DES已经成功地经受住了各种已发表的密码攻击。本文提出一种新的密码分析攻击法。在个人计算机上,这种攻击能够在几分钟内破开八圈以下的DES,并且破开十五圈以下DES的速度也比穷尽搜索来得快。这种新的攻击法适用于大量DES类型的替换/置乱密码体制,同时也显示出(尚未公开的)密码设计原则的重要作用。

关键词：密码体制 DES 差分密码分析密码分析攻击子密钥密码攻击个人计算机异或门破开数据加密标准

Spinal cord injury in the setting of traumatic thoracolumbar fracture is not reliably associated with increased risk of associated intra-abdominal injury following blunt trauma:An analysis of a National Trauma Registry database

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Chinese Journal of Traumatology 2021年第3期24卷 132-135页

作者： Veacheslav Zilbermints Yehuda Hershkovitz Kobi Peleg Joseph J.Dubose adi Givon David Aranovich Mickey Dudkiewicz Israeli Trauma Group Boris Kessel Surgical Division Hillel Yaffe Medical Center Affiliated to Rappoport Medical SchoolTechnionHaderaIsrael Department of Surgery Shamir Medical Center Affiliated to Sackler Faculty of MedicineTel Aviv UniversityTel AvivIsrael National Center for Trauma and Emergency Medicine Research Gertner Institute for Epidemiology and Health Policy ResearchTel HashomerIsrael University of Maryland School of Medicine BaltimoreMDUSA Hospital Administration Hillel Yaffe Medical CenterHaderaIsrael

Purpose:There is a common opinion that spinal fractures usually reflect the substantial impact of injuries and therefore may be used as a marker of significant associated injuries,specifically for intra-abdominal injury(IAI).The impact of concomitant spinal cord injury(SCI)with the risk of associated IAI has not been well *** aim of this study was to evaluate the incidence and severity of IAIs in patients suffering from spinal fractures with or without ***:A retrospective cohort study using the Israeli National Trauma Registry was *** with thoracic,lumbar and thoracolumbar fractures resulting from blunt mechanisms of injury from January 1,1997 to December 31,2018 were examined,comparing the incidence,severity and mortality of IAIs in patients with or without *** collected variables included age,gender,mechanism of injury,incidence and severity of the concomitant IAIs and pelvic fractures,abbreviated injury scale,injury severity score,and *** analysis was performed using GraphPad InStat?Version 3.10,with Chi-square test for independence and two sided Fisher’s exact probability ***:Review of the Israeli National Trauma Database revealed a total of 16,878 patients with spinal *** thoracic and lumbar fractures were observed in 1272 patients(7.5%),isolated thoracic fractures in 4967 patients(29.4%)and isolated lumbar fractures in 10,639 patients(63.0%).The incidence of concomitant SCI was found in 4.95%(63/1272),7.65%(380/4967)and 2.50%(266/10639)of these patients,*** overall mortality was 2.5%,proving higher among isolated thoracic fracture patient than among isolated lumbar fracture counterparts(11.3%vs.4.6%,p<0.001).Isolated thoracic fractures with SCI were significantly more likely to die than non-SCI counterparts(8.2%vs.3.1%,p<0.001).There were no differences in the incidence of IAIs between patients with or without SCI following thoracolumbar fractures overall or in isolated

关键词： Spinal fractures Blunt trauma Abdominal injuries Spinal cord injury