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Study on An Absolute Non-Collision Hash and Jumping Table IP Classification Algorithms
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作者 SHANG Feng-jun 1,2 ,PAN Ying-jun 1 1. Key Laboratory of Opto-Electronic Technology and System of Ministry of Education/College of Opto-Electronic Engineering,Chongqing University, Chongqing 400044,China 2. College of Computer Science and Technology, Chongqing University of Posts and Telecommunications, Chongqing 400065,China 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第5期835-838,共4页
In order to classify packet, we propose a novel IP classification based the non-collision hash and jumping table trie-tree (NHJTTT) algorithm, which is based on noncollision hash Trie-tree and Lakshman and Stiliadis p... In order to classify packet, we propose a novel IP classification based the non-collision hash and jumping table trie-tree (NHJTTT) algorithm, which is based on noncollision hash Trie-tree and Lakshman and Stiliadis proposing a 2-dimensional classification algorithm (LS algorithm). The core of algorithm consists of two parts: structure the non-collision hash function, which is constructed mainly based on destination/source port and protocol type field so that the hash function can avoid space explosion problem; introduce jumping table Trie-tree based LS algorithm in order to reduce time complexity. The test results show that the classification rate of NHJTTT algorithm is up to 1 million packets per second and the maximum memory consumed is 9 MB for 10 000 rules. Key words IP classification - lookup algorithm - trie-tree - non-collision hash - jumping table CLC number TN 393.06 Foundation item: Supported by the Chongqing of Posts and Telecommunications Younger Teacher Fundation (A2003-03).Biography: SHANG Feng-jun (1972-), male, Ph.D. candidate, lecture, research direction: the smart instrument and network. 展开更多
关键词 IP classification lookup algorithm trie-tree non-collision hash jumping table
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高超声速非平衡流动−辐射特性数值模拟研究
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作者 杜耀文 孙素蓉 +5 位作者 黄河激 孟显 曹进文 耿金越 闫聪 王海兴 《力学学报》 EI CAS CSCD 北大核心 2023年第12期2807-2817,共11页
飞行器高超声速飞行过程中所承受对流加热和辐射加热可能具有相当的量级,因此合理准确预测气动加热需要将二者进行综合考虑.文章发展了具有非玻尔兹曼电子能级分布和振动能级分布的高温空气碰撞辐射模型,并耦合一维激波后流动方程计算... 飞行器高超声速飞行过程中所承受对流加热和辐射加热可能具有相当的量级,因此合理准确预测气动加热需要将二者进行综合考虑.文章发展了具有非玻尔兹曼电子能级分布和振动能级分布的高温空气碰撞辐射模型,并耦合一维激波后流动方程计算不同飞行条件下激波后的非平衡流动特性,采用逐线辐射输运模型计算获得激波后非平衡辐射特性、辐射强度和辐射输运通量,深入比较分析了不同飞行高度和马赫数对非平衡流动和辐射输运过程的影响.计算结果表明对于高空高马赫飞行条件,其波后流动存在显著的热力学非平衡、化学非平衡和能级非平衡特征,在近激波区域高振动能级和原子高束缚电子激发态明显低于玻尔兹曼分布.在高空高马赫条件下真空紫外辐射占据主导地位,主要是由高能原子束缚−束缚跃迁造成的.随着高度和马赫数的下降,激波层内气体解离和电离程度降低,原子辐射贡献下降,分子辐射贡献增加,导致红外、可见光和紫外波段的辐射输运增强,真空紫外辐射输运过程减弱. 展开更多
关键词 高超声速流动 热化学非平衡 碰撞辐射模型 辐射输运
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安徽大别山及邻区区域地质调查进展与问题讨论 被引量:17
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作者 汤加富 钱存超 娄清 《中国区域地质》 CSCD 北大核心 2001年第2期128-136,共9页
通过对覆盖安徽大别山及邻区的地质调查和深入研究,重建了区内各个地段的构造地层序列及其对比方案,阐明了区内3期构造变形特征、构造型式与形成时期;确定了大量新元古代碱性变质花岗岩的存在;对榴辉岩的成因、形成时代,以及区内... 通过对覆盖安徽大别山及邻区的地质调查和深入研究,重建了区内各个地段的构造地层序列及其对比方案,阐明了区内3期构造变形特征、构造型式与形成时期;确定了大量新元古代碱性变质花岗岩的存在;对榴辉岩的成因、形成时代,以及区内是否存在蓝片岩-黄片岩-榴辉岩的变质分带等提出了不同认识。在此基础上,对大别造山带形成机理提出了非印支期碰撞造山的认识。 展开更多
关键词 大别造山带 地层序列 新元古代变质花岗岩 蓝片岩 榴辉岩 非碰撞造山作用
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青藏高原与大陆动力学——地体拼合、碰撞造山及高原隆升的深部驱动力 被引量:219
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作者 许志琴 杨经绥 +3 位作者 李海兵 张建新 曾令森 姜枚 《中国地质》 CAS CSCD 2006年第2期221-238,共18页
运用地体和地体活动论观点,提出青藏高原结构划分的新方案;强调青藏高原的形成经历了新元古代以来长期活动的过程,青藏高原是一个“非原地”诸多地体会聚、拼合以及经历复合碰撞造山的“造山的高原”;大型走滑断裂在青藏高原形成中起着... 运用地体和地体活动论观点,提出青藏高原结构划分的新方案;强调青藏高原的形成经历了新元古代以来长期活动的过程,青藏高原是一个“非原地”诸多地体会聚、拼合以及经历复合碰撞造山的“造山的高原”;大型走滑断裂在青藏高原形成中起着地体相对位移、侧向挤出、移置及使高原几何形态扭曲的作用。提出青藏高原隆升的“南缘超深俯冲(>600km)、北缘陆内俯冲、腹地深部热结构及岩石圈范围内的向NE右旋隆升”的多元驱动力机制。 展开更多
关键词 青藏高原 非原地地体拼合 复合碰撞造山 走滑构造 多元驱动力
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基于气体放电等离子体射流源的模拟离子引出实验平台物理特性 被引量:1
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作者 陈坚 刘志强 +3 位作者 郭恒 李和平 姜东君 周明胜 《物理学报》 SCIE EI CAS CSCD 北大核心 2018年第18期44-54,共11页
离子引出过程是原子蒸气激光同位素分离中非常重要的物理过程之一,而其中关键的等离子体参数(等离子体初始密度和电子温度等)均会对离子引出特性产生影响.基于千赫兹电源驱动的氩气高压交流放电等离子体射流源,建立了离子引出模拟实验平... 离子引出过程是原子蒸气激光同位素分离中非常重要的物理过程之一,而其中关键的等离子体参数(等离子体初始密度和电子温度等)均会对离子引出特性产生影响.基于千赫兹电源驱动的氩气高压交流放电等离子体射流源,建立了离子引出模拟实验平台-2015 (IEX-2015),开发了用于诊断氩等离子体参数的"碰撞-辐射"模型,对等离子体射流区的电子温度和电子数密度等关键参数进行了测量.结果表明,电源输入功率和驱动频率以及工作气体流量均会对等离子体射流区的电子温度和数密度产生影响;在真空腔压强为10^(-2)Pa量级下,射流区电子数密度和电子温度的可调参数范围分别为10~9—10^(11)cm^(-3)和1.7—2.8 e V,这与实际离子引出过程中的等离子体参数范围相近.在此基础上,开展了不同引出电压、极板间距和电子数密度条件下初步的离子引出实验,所得到的离子引出电流变化规律亦与实际原子蒸气激光同位素分离中的离子引出特性定性一致.上述研究结果验证了在IEX-2015上开展离子引出模拟实验的可行性,为后续深入开展离子引出特性的实验研究准备了良好的条件. 展开更多
关键词 离子引出 低气压放电 非平衡态等离子体 “碰撞-辐射”模型
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Determination of Non-Maxwellian Electron Energy Distributions in Low-Pressure Plasmas by Using the Optical Emission Spectroscopy and a Collisional-Radiative Model
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作者 朱悉铭 蒲以康 《Plasma Science and Technology》 SCIE EI CAS CSCD 2011年第3期267-278,共12页
A Maxwellian electron energy distribution function (EEDF) is often assumed when using the optical emission line-ratio method to determine the electron temperature in low- temperature plasmas. However, in many cases,... A Maxwellian electron energy distribution function (EEDF) is often assumed when using the optical emission line-ratio method to determine the electron temperature in low- temperature plasmas. However, in many cases, non-Maxwellian EEDFs can be formed due to the non-local electron heating or the inelastic-collisional energy loss processes. In this work, with a collisional-radiative model, we propose an approach to obtain the non-Maxwellian EEDF with a 'two-temperature structure' from the emission line-ratios of Paschen 2p levels of argon and kryp- ton atoms. For applications of this approach in reactive gas (CF4, O2, etc) discharges that contain argon and krypton, recommendations of some specific emission line-ratios are provided, according to their sensitivities to the EEDF variation. The kinetic processes of the relevant excited atoms are also discussed in detail. 展开更多
关键词 plasma diagnostics optical emission spectroscopy non-Maxwellian EEDF collisional-radiative model
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Design optimization of a hexapod vibration isolation system for electro-optical payload
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作者 Jing LI Weipeng LI +1 位作者 Xiaoyan ZHANG Hai HUANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第2期330-342,共13页
The electro-optical payloads on mobile platforms generally suffer undesirable vibrations generated by maneuvers and turbulence.These vibrations are in six degrees of freedom and cause line-of-sight jitters,resulting i... The electro-optical payloads on mobile platforms generally suffer undesirable vibrations generated by maneuvers and turbulence.These vibrations are in six degrees of freedom and cause line-of-sight jitters,resulting in image blurring and loss of tracking accuracy.In this paper,a Hexapod Vibration Isolation System(HVIS)is proposed and optimized to solve this problem.The optimization aims to centralize and minimize the natural frequencies of HVIS,for expanding the vibration isolation bandwidth and improving the vibration isolation in the higher frequency band.Considering that the design space for HVIS is limited and interfered with the frames of the mobile platform,a non-collision algorithm is proposed and applied in the optimization to obtain the feasible optimal design.The optimization result shows that the natural frequency bandwidth has been reduced by 42.9%,and the maximum natural frequency is reduced by 30.2%.The prototypes of initial and optimal designs are manufactured and tested.Both simulated and experimental results demonstrate the validity of the optimization,and the optimal design provides a maximum of 15 dB more isolation in rotation direction than the initial design. 展开更多
关键词 Electro-optical payload Vibrations Isolation system HEXAPOD OPTIMIZATION non-collision design
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