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无线传感器网络复件攻击的移动检测方法
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作者 陈向益 王良民 詹永照 《通信学报》 EI CSCD 北大核心 2012年第S1期178-185,共8页
无线传感器网络无人值守的特性使得它易于遭受复件攻击从而造成严重的安全隐患。提出了一个移动检测复件攻击的方法,通过检测节点的移动使得网络内的每个节点都能直接与检测节点通信,从而使得检测节点与一跳范围内的传感器节点能够直接... 无线传感器网络无人值守的特性使得它易于遭受复件攻击从而造成严重的安全隐患。提出了一个移动检测复件攻击的方法,通过检测节点的移动使得网络内的每个节点都能直接与检测节点通信,从而使得检测节点与一跳范围内的传感器节点能够直接通信,从而全局地检测到网络中的复件攻击节点,并采用更新网络对称密钥的方法防御逃避检测的节点。实验表明该方法能够检测到网络内的所有复件攻击节点,和其他方法相比,本方法不需要检测消息的转发,检测开销小并且实现了开销在网络中的均衡。 展开更多
关键词 无线传感器网络 复件攻击 移动检测
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R2:一种增强Web服务可信度的代表元-复件模型
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作者 沈洁 赵培欣 +1 位作者 张亮 施伯乐 《计算机研究与发展》 EI CSCD 北大核心 2007年第z3期35-39,共5页
作为面向服务架构SOA的一种主要形式,Web服务具有开放、松耦合和平台独立的特性,被认为是未来主要的软件模式.然而,其分布式特性也对Web服务的组织、运行与管理提出了新的挑战.现有的SOA模型主要关注Web服务的静态信息,无法在瞬息万变... 作为面向服务架构SOA的一种主要形式,Web服务具有开放、松耦合和平台独立的特性,被认为是未来主要的软件模式.然而,其分布式特性也对Web服务的组织、运行与管理提出了新的挑战.现有的SOA模型主要关注Web服务的静态信息,无法在瞬息万变的网络环境中保证Web服务运行时的可靠性和效率.为此提出了一种基于代表元-复件的模型,该模型以代表元作为一组可替换Web服务的抽象,同时以复件的形式来保证代表元的可生存性,从而提高了Web服务在调用时的可靠性和效率. 展开更多
关键词 WEB服务 可生存性 复件 动态绑定
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复件操作系统汉语语言交互控制研究
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作者 吴晓帆 吴涛 《科技信息》 2008年第36期19-19,30,共2页
目前人们与计算机交互的主要方式还是基于键盘和鼠标。研究了在图形界面下操作系统自然语言交互的过程,构造了一个语音交互和指令驱动平台,实现了在图形交互环境下用汉语语言控制操作系统功能执行的目标,使计算机具备了基于自然语言的... 目前人们与计算机交互的主要方式还是基于键盘和鼠标。研究了在图形界面下操作系统自然语言交互的过程,构造了一个语音交互和指令驱动平台,实现了在图形交互环境下用汉语语言控制操作系统功能执行的目标,使计算机具备了基于自然语言的交互能力。 展开更多
关键词 自然语言 可视化交互 消息机制 挂接技术 复件 操作系统 汉语语言 交互控制
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利用大事记减少重复件进馆
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作者 秦远久 《四川档案》 北大核心 1994年第1期24-25,共2页
利用大事记减少重复件进馆丰都县档案局(648200)秦远久在机关、团体、企事业单位的档案材料中,都少不了有人事任免、职称评聘、表彰先进、处理问题、下达计划等需要永久保存的大事记。这些内容极其丰富、事件至关重要的大事,... 利用大事记减少重复件进馆丰都县档案局(648200)秦远久在机关、团体、企事业单位的档案材料中,都少不了有人事任免、职称评聘、表彰先进、处理问题、下达计划等需要永久保存的大事记。这些内容极其丰富、事件至关重要的大事,很多出自收发文单位的文件内。笔者认... 展开更多
关键词 大事记 复件 档案馆 发文机关 重复文件 进馆工作 人大常委 短期保存 职称评聘 记录不全
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Censored Composite Conditional Quantile Screening for High-Dimensional Survival Data
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作者 LIU Wei LI Yingqiu 《应用概率统计》 CSCD 北大核心 2024年第5期783-799,共17页
In this paper,we introduce the censored composite conditional quantile coefficient(cC-CQC)to rank the relative importance of each predictor in high-dimensional censored regression.The cCCQC takes advantage of all usef... In this paper,we introduce the censored composite conditional quantile coefficient(cC-CQC)to rank the relative importance of each predictor in high-dimensional censored regression.The cCCQC takes advantage of all useful information across quantiles and can detect nonlinear effects including interactions and heterogeneity,effectively.Furthermore,the proposed screening method based on cCCQC is robust to the existence of outliers and enjoys the sure screening property.Simulation results demonstrate that the proposed method performs competitively on survival datasets of high-dimensional predictors,particularly when the variables are highly correlated. 展开更多
关键词 high-dimensional survival data censored composite conditional quantile coefficient sure screening property rank consistency property
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Process Optimization of Cu-en/AP Composite Microspheres Preparation by Electrostatic Spray Method Based on ANSYS Simulation
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作者 LIU Lei HU Tian-yuan +1 位作者 SONG Ming-jun JI Wei 《火炸药学报》 EI CAS CSCD 北大核心 2024年第10期899-909,I0002,共12页
To investigate the process optimizationof Cu-en/AP composite microspheres preparation via electrostatic spraying,and to reveal the effects of droplet properties and flow rate variations on the experimental results dur... To investigate the process optimizationof Cu-en/AP composite microspheres preparation via electrostatic spraying,and to reveal the effects of droplet properties and flow rate variations on the experimental results during the electrostatic spraying process,the prepared process parameters of Cu-en/AP composite microspheres by electrostatic spray method under the orthogonal experimental design simulated by ANSYS(Fluent).The influence of flow rate,solvent ratio,and solid mass on the experimental results is examined using a controlled variable method.The results indicate that under the conditions of a flow rate of 2.67×10^(-3)kg/s an acetone-to-deionized water ratio of 1.5∶1.0,and a solid mass of 200 mg,the theoretical particle size of the composite microspheres can reach e nanoscale.Droplet trajectories in the electric field remain stable without significant deviation.The simulation results show that particle diameter decreases with increasing flow rate,with the trend leveling off around a flow rate of 1×10^(-3)kg/s.As the solvent ratio increases(with higher acetone content),particle diameter initially decreases,reaching a minimum around a ratio of 1.5∶1.0 before gradually increasing.Increasing the solid mass also reduces the particle diameter,with a linear increase in diameter observed at around 220 mg.Cu-en/AP composite microspheres with nanoscale dimensions were confirmed under these conditions by the final SEM images. 展开更多
关键词 physical chemistry fluent simulation ammonium perchlorate composite microspheres electrostatic spray process conditions
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人Sox2基因的克隆表达和纯化 被引量:4
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作者 张琦 忻珍桦 +6 位作者 蔡引凤 高云霞 沙红英 刘思国 陈建泉 张爱民 成国祥 《华中师范大学学报(自然科学版)》 CAS CSCD 2008年第1期102-105,共4页
应用RT-PCR方法从人胚胎干细胞中扩增出Sox2基因,构建pET28b-Sox2表达载体.用IPTG诱导转化pET28b-Sox2表达载体的大肠杆菌BL21(DE3),并优化表达条件为37℃IPTG0.8 mmol/L诱导4 h.以Ni-NTA亲和层析法纯化Sox2重组蛋白,对变性蛋白进行柱... 应用RT-PCR方法从人胚胎干细胞中扩增出Sox2基因,构建pET28b-Sox2表达载体.用IPTG诱导转化pET28b-Sox2表达载体的大肠杆菌BL21(DE3),并优化表达条件为37℃IPTG0.8 mmol/L诱导4 h.以Ni-NTA亲和层析法纯化Sox2重组蛋白,对变性蛋白进行柱上和透析复性,复性后蛋白得率为0.7 mg/g湿菌重. 展开更多
关键词 SOX2 原核表达 纯化 复件
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拜占庭容错服务的适应性失效检测研究 被引量:3
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作者 董辉 杨金民 张大方 《微电子学与计算机》 CSCD 北大核心 2006年第9期60-62,共3页
文章在Byzantinefaulttolerant状态机复制容错算法(BFT)中增加适应性失效检测。根据拜占庭容错服务应用需求和运行环境动态调整失效检测时间,适应性好,能满足BFT失效检测要求。当主复件失效时,可以缩短视图切换时间,减少系统响应时间,... 文章在Byzantinefaulttolerant状态机复制容错算法(BFT)中增加适应性失效检测。根据拜占庭容错服务应用需求和运行环境动态调整失效检测时间,适应性好,能满足BFT失效检测要求。当主复件失效时,可以缩短视图切换时间,减少系统响应时间,提高系统可用性。 展开更多
关键词 拜占庭容错 复件 视图 失效检测 适应性
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《归档文件整理规则》的“件”型探析 被引量:2
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作者 邹吉辉 《四川档案》 北大核心 2004年第2期8-9,共2页
本文根据“整理规则”,把《归档文件整理规则》所列的七种“件”型分单件与复件,复件又分为不可分复件与可分复件、联合复件与偏正复件、承接复件、并列复件、主从复件、补充复件等类型,提出了复件整理与编目的特殊方法并说明这一研究... 本文根据“整理规则”,把《归档文件整理规则》所列的七种“件”型分单件与复件,复件又分为不可分复件与可分复件、联合复件与偏正复件、承接复件、并列复件、主从复件、补充复件等类型,提出了复件整理与编目的特殊方法并说明这一研究的理论与实践意义。 展开更多
关键词 《归档文件整理规则》 整理单位 文件级管理 单件 复件组合 编目工作
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Windows系统静态取证技术研究 被引量:1
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作者 谭安芬 《电子工程师》 2007年第10期49-51,共3页
随着计算机技术的发展和信息化的普及,计算机犯罪事件频繁发生,如何最大限度地获取计算机犯罪相关的电子证据,其中涉及的技术就是计算机取证技术。计算机取证包括对计算机犯罪现场数据的确认、保护、提取、分析。文中对W indows系统被... 随着计算机技术的发展和信息化的普及,计算机犯罪事件频繁发生,如何最大限度地获取计算机犯罪相关的电子证据,其中涉及的技术就是计算机取证技术。计算机取证包括对计算机犯罪现场数据的确认、保护、提取、分析。文中对W indows系统被动取证的相关技术进行深入的研究和探讨,在犯罪事件发生后对犯罪行为进行事后的取证,存在着证据的真实性、有效性和及时性问题。计算机取证收集的证据往往是海量的,而且来源复杂,格式不一,文中重点分析了取证过程中如何生成鉴定复件、证据的来源、如何收集分析证据、如何保全证据。 展开更多
关键词 WINDOWS系统 静态取证 复件 收集证据 分析证据
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谈“天显通宝”
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作者 高俊武 《内蒙古金融研究》 2003年第S2期86-87,共2页
我拜读了《内蒙古金融》1987年钱币专刊1、2期,几位泉家对辽"天显通宝"有争论。笔者认为他们没有收藏品及实物,现把60年前锦州市"惠记古玩店"出售的"天显通宝"现存照片复件(现为过去惠记古玩店一家属收... 我拜读了《内蒙古金融》1987年钱币专刊1、2期,几位泉家对辽"天显通宝"有争论。笔者认为他们没有收藏品及实物,现把60年前锦州市"惠记古玩店"出售的"天显通宝"现存照片复件(现为过去惠记古玩店一家属收藏),以及自己的收藏照寄去,望各泉家讨论。关于辽代天显通宝,海内外传说纷纭,为早日同广大钱币爱好者见面,现将天显通宝原拓彩照及60年前由锦州市" 展开更多
关键词 锦州市 内蒙古 钱币 古钱 复件 照片 辽代 原拓 收藏品 博物馆藏品
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Case studies on testing with compositional metamorphic relations 被引量:1
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作者 董国伟 徐宝文 +2 位作者 陈林 聂长海 王璐璐 《Journal of Southeast University(English Edition)》 EI CAS 2008年第4期437-443,共7页
Some metamorphic relations (MR) are not good at detecting faults in metamorphic testing. In this paper, the method of making compositional MR (CMR) based on the speculative law of proposition logic is presented. T... Some metamorphic relations (MR) are not good at detecting faults in metamorphic testing. In this paper, the method of making compositional MR (CMR) based on the speculative law of proposition logic is presented. This method constructs new MRs by composing existing MRs in a pairwise way. Because CMR contains all the advantages of the MRs that form it, its fault detection performance is wonderful. On the other hand, the number of relations will decrease greatly after composing, so a program can be tested with much fewer test cases when CMRs are used. In order to research the characteristics of a CMR, two case studies are analyzed. The experimental results show that the CMR's performance is mostly determined by the central MRs forming it and the sequence of composition. Testing efficiency is improved greatly when CMRs are used. 展开更多
关键词 software testing metamorphic testing compositional metamorphic relation
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The Order of Approximation by Complex Rational Type Interpolating Operators at Fejer's Points 被引量:1
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作者 王子玉 朱长青 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第3期66-70,共5页
In this paper, supose Γ be a boundary of a Jordan domain D and Γ satisfied Альпер condition, the order that rational type interpolating operators at Fejer's points of f(z)∈C(Γ) converge to f(z) in the se... In this paper, supose Γ be a boundary of a Jordan domain D and Γ satisfied Альпер condition, the order that rational type interpolating operators at Fejer's points of f(z)∈C(Γ) converge to f(z) in the sense of uniformly convergence is obtained. 展开更多
关键词 rational type interpolation Fejer's points order of approximation Jordan domain
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机电
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《中国.城乡桥》 2001年第10期14-15,共2页
不锈钢纤维生产技术 高科技产品不锈钢纤维具有强度高、耐高温、不变形、稳定性能好、抗腐蚀能力强和较好的屏蔽、防磁、防辐射等优点,被广泛应用于航空、航天、石油、化工、军工等工业领域,应用范围正不断拓展,发展前景十分诱人。 目前... 不锈钢纤维生产技术 高科技产品不锈钢纤维具有强度高、耐高温、不变形、稳定性能好、抗腐蚀能力强和较好的屏蔽、防磁、防辐射等优点,被广泛应用于航空、航天、石油、化工、军工等工业领域,应用范围正不断拓展,发展前景十分诱人。 目前,我国年需直径0.02~0.04毫米的不锈钢纤维约5000吨左右。 展开更多
关键词 机电 不锈钢纤维 合作方式 车尾灯 复新技术 车筐 复件 蕃薯 醛类 技术转让费
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尤溪:人大代表建议办理“回头看”
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作者 张玉华 《人民政坛》 2005年第9期34-34,共1页
现实工作中,一些政府及有关部门在办理代表建议中,存在重答复轻落实,或文来文往,或办理过程中敷衍了事,或推诿扯皮的现象。尤溪县人大常委会采取与代表面对面听取办理建议的意见、再督促有关部门办理的做法,对提高建议办理质量来说,是... 现实工作中,一些政府及有关部门在办理代表建议中,存在重答复轻落实,或文来文往,或办理过程中敷衍了事,或推诿扯皮的现象。尤溪县人大常委会采取与代表面对面听取办理建议的意见、再督促有关部门办理的做法,对提高建议办理质量来说,是个有益的尝试。 展开更多
关键词 人大代表 建议 人大常委会 黄道光 会议代表 尤溪县 城关镇 回头看 复件 答复
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Approximate Iteration Detection and Precoding in Massive MIMO 被引量:5
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作者 Chuan Tang Yerong Tao +3 位作者 Yancang Chen Cang Liu Luechao Yuan Zuocheng Xing 《China Communications》 SCIE CSCD 2018年第5期183-196,共14页
Massive multiple-input multiple-output provides improved energy efficiency and spectral efficiency in 5 G. However it requires large-scale matrix computation with tremendous complexity, especially for data detection a... Massive multiple-input multiple-output provides improved energy efficiency and spectral efficiency in 5 G. However it requires large-scale matrix computation with tremendous complexity, especially for data detection and precoding. Recently, many detection and precoding methods were proposed using approximate iteration methods, which meet the demand of precision with low complexity. In this paper, we compare these approximate iteration methods in precision and complexity, and then improve these methods with iteration refinement at the cost of little complexity and no extra hardware resource. By derivation, our proposal is a combination of three approximate iteration methods in essence and provides remarkable precision improvement on desired vectors. The results show that our proposal provides 27%-83% normalized mean-squared error improvement of the detection symbol vector and precoding symbol vector. Moreover, we find the bit-error rate is mainly controlled by soft-input soft-output Viterbi decoding when using approximate iteration methods. Further, only considering the effect on soft-input soft-output Viterbi decoding, the simulation results show that using a rough estimation for the filter matrix of minimum mean square error detection to calculating log-likelihood ratio could provideenough good bit-error rate performance, especially when the ratio of base station antennas number and the users number is not too large. 展开更多
关键词 massive MIMO detection and precoding matrix inversion iteration refinement soft Viterbi decoding
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p53-expressing conditionally replicative adenovirus CNHK500-p53 against hepatocellular carcinoma in vitro 被引量:4
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作者 Hong-Chuan Zhao Qi Zhang Yang Yang Min-Qiang Lu Hua Li Chi Xu Gui-Hua Chen 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第5期683-691,共9页
AIM: To develop a conditionally replicative gene-viral vector system called CNHK500-p53, which contains dual promoters within the E1 region, and combines the advantages of oncolytic virus and gene therapies for hepat... AIM: To develop a conditionally replicative gene-viral vector system called CNHK500-p53, which contains dual promoters within the E1 region, and combines the advantages of oncolytic virus and gene therapies for hepatocellular carcinoma (HCC). METHODS: CNHK500-p53 was constructed by using human telomerase reverse transcriptase (hTERT) promoter to drive adenovirus E1a gene and hypoxia response element (HRE) promoter to drive adenovirus E1b gene. p53 gene expressing cassette was inserted into the genome of replicative virus. Viral replication experiments, cytopathic effect (CPE) and methyl thiazolyl tetrazolium (MTT) assay were performed to test the selective replication and oncolytic efficacy of CNHK500-p53. RESULTS: Immunohistochemistry verified that infection with CNHK500-p53 was associated with selective replication of adenovirus and production of p53 protein in telomerase-positive and hypoxia-inducible factordependent HCC cells, p53 protein secreted from HepG2, infected with CNHK500-p53 was significantly higher than that infected with nonreplicative adenovirus Ad-p53 in vitro (388 ± 34.6 μg/L vs 76.3 ± 13.17 μg/L). Viral replication experiments showed that replication of CNHK500-p53 and CNHK500 or WtAd5, was much stronger than that of Ad-p53 in tested HCC cell lines. CPE and H1-F assay indicated that CNHK500-p53 selectively replicated in and killed HCC cells while leaving normal cells unaffected. CONCLUSION: A more efficient gene-viral system is developed by combining selective oncolysis with exogenous expression of p53 against HCC cells. 展开更多
关键词 Conditionally replicative adenovirus Oncolytic virotherapy Gene therapy p53 gene Hepatocellular carcinoma
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Common reflection surface stack using dip decomposition for rugged surface topography 被引量:6
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作者 Sun Xiaodong Li Zhenchun Teng Houhua 《Applied Geophysics》 SCIE CSCD 2007年第1期45-50,共6页
We present an extension of the Common Reflection Surface (CRS) stack that provides support for an arbitrary top surface topography. CRS stacking can be applied to the original prestack data without the need for any ... We present an extension of the Common Reflection Surface (CRS) stack that provides support for an arbitrary top surface topography. CRS stacking can be applied to the original prestack data without the need for any elevation statics. The CRS-stacked zero- offset section can be corrected (redatumed) to a given planar level by kinematic wave field attributes. The seismic processing results indicate that the CRS stacked section for rugged surface topography is better than the conventional stacked section for S/N ratio and better continuity of reflection events. Considering the multiple paths of zero-offset rays, the method deals with reflection information coming from different dips and performs the stack using the method of dip decomposition, which improves the kinematic and dynamic character of CRS stacked sections. 展开更多
关键词 static correction CRS stack kinematic parameters REDATUMING dip decomposition.
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Research on 1-3 Orthogonal Anisotropic Piezoelectric Composite Material Sensors- 被引量:1
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作者 熊克 张为公 骆英 《Journal of Southeast University(English Edition)》 EI CAS 2002年第2期136-140,共5页
Piezoelectric composite material (PCM) is an important branch of modernsensor and actuator materials with wide applications in smart structures. In this paper, based onpiezoelectric ceramic, composite and experimental... Piezoelectric composite material (PCM) is an important branch of modernsensor and actuator materials with wide applications in smart structures. In this paper, based onpiezoelectric ceramic, composite and experimental mechanics theories, a kind of 1-3 orthogonalanisotropic PCM (OAPCM) sensor is developed, and the sensing principle is analyzed to describesensor behaviors. In order to determine strain and stress on isotropic or orthogonal anisotropiccomponent surface, the relationships between strain and stress are established. The experimentalresearch on 1-3 OAPCM sensor is carried out in uniaxial and biaxial stress states. The results showthat 1-3 OAPCM sensors offer orthotropic properties of piezoelectricity, and sensing equations canbe used for strain or stress measurement with good accuracy. 展开更多
关键词 1-3 PCM orthogonal anisotropic SENSOR strain-stress relationship
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Reflection of Typhoon Morakot-The Challenge of Compound Disaster Simulation 被引量:1
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作者 CHEN Yu-Shiu KUO Yu-Shu +4 位作者 LAI Wen-Chi TSAI Yuan-Jung LEE Shin-Ping CHEN Kun-Ting SHIEH Chjeng-Lun 《Journal of Mountain Science》 SCIE CSCD 2011年第4期571-581,共11页
Climate change has altered locally singletype disasters to large-scale compound disasters because of increasing intensity and frequency of extreme rainfall events.The compound disasters can combine small-scale floods,... Climate change has altered locally singletype disasters to large-scale compound disasters because of increasing intensity and frequency of extreme rainfall events.The compound disasters can combine small-scale floods,debris flows,shallow landslides,deep-seated landslides,and landslide lakes into a large-scale single disaster event.Although simulation models and evaluation tools are available for single-type disasters,no single model is well developed for compound disasters due to the difficulty of handling the interrelationship between two successive single-type disasters.This study proposes a structure for linking available single-type simulation models to evaluate compound disasters and provides a useful tool of decision making for warning and planning of disaster reduction. 展开更多
关键词 Typhoon Morakot Compound disaster Hsiaolin Village
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