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Generalized fuzzy ideals of near-rings 被引量:1
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作者 ZHAN Jian-ming Davvaz B. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2009年第3期343-349,共7页
The concept of(∈,∈∨q)-fuzzy subnear-rings(ideals) of a near-ring is introduced and some of its related properties are investigated.In particular,the relationships among ordinary fuzzy subnear-rings(ideals),(... The concept of(∈,∈∨q)-fuzzy subnear-rings(ideals) of a near-ring is introduced and some of its related properties are investigated.In particular,the relationships among ordinary fuzzy subnear-rings(ideals),(∈,∈∨ q)-fuzzy subnear-rings(ideals) and(∈,∈∨q)-fuzzy subnear-rings(ideals) of near-rings are described.Finally,some characterization of [μ]t is given by means of(∈,∈∨ q)-fuzzy ideals. 展开更多
关键词 near-RING subnear-ring (ideal) (∈ q)-fuzzy subnear-ring (ideal) (∈ ∈∨ q)-fuzzy subnear-ring(ideal)
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Redefined generalized fuzzy ideals of near-rings 被引量:1
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作者 ZHAN Jian-ming YIN Yun-qiang 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2010年第3期341-348,共8页
With a new idea, we redefine generalized fuzzy subnear-rings (ideals) of a near- ring and investigate some of its related properties. Some new characterizations are given. In particular, we introduce the concepts of... With a new idea, we redefine generalized fuzzy subnear-rings (ideals) of a near- ring and investigate some of its related properties. Some new characterizations are given. In particular, we introduce the concepts of strong prime (or semiprime) (∈, ∈∨ q)-fuzzy ideals of near-rings, and discuss the relationship between strong prime (or semiprime) (∈, ∈∨ q)-fuzzy ideals and prime (or semiprime) (∈, ∈∨ q)-fuzzy ideals of near-rings. 展开更多
关键词 near-RING subnear-ring (ideal) (∈^- ∈^-∨ q^-)-fuzzy subnear-ring (ideal) prime (semiprime) (∈ ∈∨ q)-fuzzy subnear-ring (ideal).
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几类near MDS码和最优局部修复码的构造
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作者 王鑫然 衡子灵 《电子学报》 EI CAS CSCD 北大核心 2024年第3期957-966,共10页
局部修复码是一种通过局部修复提高存储节点修复效率的重要编码方法,在分布式存储和云存储中有重要应用.本文首先构造了几类维数为4或5的near MDS(near Maximum Distance Separable)码,精确计算出了它们的参数和重量分布.特别地,得到了... 局部修复码是一种通过局部修复提高存储节点修复效率的重要编码方法,在分布式存储和云存储中有重要应用.本文首先构造了几类维数为4或5的near MDS(near Maximum Distance Separable)码,精确计算出了它们的参数和重量分布.特别地,得到了一些参数相同但重量分布不同的near MDS码.此外,通过确定near MDS码的局部度,得到了几类距离最优和维数最优的局部修复码.这些局部修复码的参数和文献中已知最优局部修复码的参数不同. 展开更多
关键词 near MDS码 重量分布 局部修复码 分布式存储
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Near Infrared Spectroscopy (NIRS) Model-Based Prediction for Protein Content in Cowpea
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作者 Kavera Biradar Waltram Ravelombola +1 位作者 Aurora Manley Caroline Ruhl 《American Journal of Plant Sciences》 CAS 2024年第3期145-160,共16页
Cowpea (Vigna unguiculata L. Walp) is a multi-purpose legume with high quality protein for human consumption and livestock. The objective of this work was to develop near-infrared spectroscopy (NIRS) prediction models... Cowpea (Vigna unguiculata L. Walp) is a multi-purpose legume with high quality protein for human consumption and livestock. The objective of this work was to develop near-infrared spectroscopy (NIRS) prediction models to estimate protein content in cowpea. A total of 116 cowpea breeding lines with a wide range of protein contents (19.28 % to 32.04%) were selected to build the model using whole seed and ground seed samples. Partial least-squares discriminant analysis (PLS-DA) regression technique with different pre-treatments (derivatives, standard normal variate, and multiplicative scatter correction) were carried out to develop the protein prediction model. Results showed: 1) spectral plots of both the whole seed and ground seed showed higher spectral scatter at higher wavelengths (>1450 nm), 2) data pre-processing affects prediction accuracy for bot whole seed and ground seed samples, 3) prediction using ground seed samples (0.64 R<sup>2</sup> 0.85) is better than the whole seed (0.33 R<sup>2</sup> 0.78), and 4) the data pre-processing second derivative with standard normal variate has the best prediction (R<sup>2</sup>_whole seed = 0.78, R<sup>2</sup>_ground seed = 0.85). The results will be of interest in cowpea breeding programs aimed at improving total seed protein content. 展开更多
关键词 COWPEA GERMPLASM PROTEIN near-Infrared Spectroscopy (NIRS) Partial Least Squares (PLS)
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An Introduction to the Theory of Matrix Near-Rings
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作者 Saviour Chibeti Iness Kyapwanyama 《Advances in Pure Mathematics》 2023年第2期71-95,共25页
Matrix rings are prominent in abstract algebra. In this paper we give an overview of the theory of matrix near-rings. A near-ring differs from a ring in that it does not need to be abelian and one of the distributive ... Matrix rings are prominent in abstract algebra. In this paper we give an overview of the theory of matrix near-rings. A near-ring differs from a ring in that it does not need to be abelian and one of the distributive laws does not hold in general. We introduce two ways in which matrix near-rings can be defined and discuss the structure of each. One is as given by Beildeman and the other is as defined by Meldrum. Beildeman defined his matrix near-rings as normal arrays under the operation of matrix multiplication and addition. He showed that we have a matrix near-ring over a near-ring if, and only if, it is a ring. In this case it is not possible to obtain a matrix near-ring from a proper near-ring. Later, in 1986, Meldrum and van der Walt defined matrix near-rings over a near-ring as mappings from the direct sum of n copies of the additive group of the near-ring to itself. In this case it can be shown that a proper near-ring is obtained. We prove several properties, introduce some special matrices and show that a matrix notation can be introduced to make calculations easier, provided that n is small. 展开更多
关键词 near-RINGS First near-Ring Isomorphism Zero Symmetric near-Ring near-Ring Module and Matrix near-Rings
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Progress and trend on near-field problems in civil engineering 被引量:1
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作者 李爽 谢礼立 《Acta Seismologica Sinica(English Edition)》 CSCD 2007年第1期105-114,共10页
In the last twenty years, near-field problems became an important topic for both seismologists and civil engineers. The one aspect is to illuminate mechanisms of earthquakes and explain new phenomena. The another aspe... In the last twenty years, near-field problems became an important topic for both seismologists and civil engineers. The one aspect is to illuminate mechanisms of earthquakes and explain new phenomena. The another aspect is the ground motions, which are usually assigned by engineers as a type of input load for seismic design of structures, sometimes can control the final design results. The experiments, performance evaluations and other related aspects are all based on the specified type of load. As a result, many aspects related to civil engineering will be influenced by changes of the type of load, Hence, the characteristics of the load and the corresponding response of structures are desired for studying. In this paper, the state-of-the-art of near-field problems in civil engineering is comprehensively reviewed, which include inherent characteristics of near-field ground motions and influences of these ground motions on civil structures. The existing problems are pointed out and work needed to be further investigated in the future is suggested. It is believed that the information in this paper can be useful to advance the state of investigation on near-field problems. 展开更多
关键词 near-FIELD near-FAULT near-source inherent characteristics of ground motions influences on civil structures
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由群决定的Near环
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作者 左连翠 赵娥 《济南大学学报(社会科学版)》 1996年第2期56-58,共3页
本文在任意群的全体映射集合上定义了加法及乘法运算,证明了它恰好能做成一个Near环,讨论了有单位元的Near环与映射的Near环之间的关系.最后给出了一般群的自同态集合能作成Near环的充要条件.
关键词 映射 near 映射near
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自由Near环的构造及有关结果
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作者 郑玉美 《湖北大学学报(自然科学版)》 CAS 1991年第4期335-340,共6页
为了建立Near环的PI理论,本文构造了一个自由Near环NF(X),接着证明了DN(x)=:NF(X)/J是一个自由分配Near环,当X为可交换未定元集时DN(ξ)是一个自由交换Near环,最后由自由交换Near环DN(ξ)得到一个交换整环。
关键词 自由分配 near 自由near
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一类特殊的near-perfect数(英文) 被引量:2
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作者 李建 廖群英 《中国科学技术大学学报》 CAS CSCD 北大核心 2017年第11期906-911,共6页
设正整数α≥2,p_1,p_2为奇质数且p_1<p_2.利用初等的方法和技巧,证明了不存在形如2^(α-1) p_1~2p_2~2的以d∈{1,p_1~2,p_2~2,p_1p_2,p_1p_2~2,p_1~2p_2}为冗余因子的near-perfect数,并给出存在形如2^(α-1) p_1~2p_2~2的以d∈{p_1,... 设正整数α≥2,p_1,p_2为奇质数且p_1<p_2.利用初等的方法和技巧,证明了不存在形如2^(α-1) p_1~2p_2~2的以d∈{1,p_1~2,p_2~2,p_1p_2,p_1p_2~2,p_1~2p_2}为冗余因子的near-perfect数,并给出存在形如2^(α-1) p_1~2p_2~2的以d∈{p_1,p_2}为冗余因子的near-perfect数的一个等价刻画.进而,给定正整数k≥2,通过推广near-perfect数的定义至k弱near-perfect数,证明了当k≥3时,不存在形如2^(α-1) p_1~2p_2~2的以d∈{p_1~2,p_2~2}为冗余因子的k弱near-perfect数. 展开更多
关键词 perfect数 near-perfect数 冗余因子 k弱near-perfect数
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关于素Near-环的微商
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作者 刘永辉 《湖南教育学院学报》 1997年第2期31-33,共3页
本文将魏宗宣关于原环求导的一个定理推广到素Near-环上.主要结果是:设N是一个2-扭自由的素Near-环,d是N的一个非平凡微商.Z为N的中心,I是N的非零理想,如果d(I)Z,则N是可换环.
关键词 near-环 微商 可换环 near 理想
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地铁工程Near-miss知识库构建 被引量:6
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作者 邓小鹏 周志鹏 +1 位作者 李启明 吴伟巍 《东南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2010年第5期1103-1109,共7页
针对目前地铁施工的安全管理问题,引入Near-miss(未遂事件或险兆事件)概念,构建出地铁工程的Near-miss知识库.首先,分析了地铁工程Near-miss知识的5种来源,并通过对地铁工程事故数据库的分析,得到地铁工程Near-miss知识.然后,从人员身... 针对目前地铁施工的安全管理问题,引入Near-miss(未遂事件或险兆事件)概念,构建出地铁工程的Near-miss知识库.首先,分析了地铁工程Near-miss知识的5种来源,并通过对地铁工程事故数据库的分析,得到地铁工程Near-miss知识.然后,从人员身份、机械状态、材料状态、环境状况和相互位置等5个方面对地铁工程Near-miss知识进行框架表示,并根据其特点,研究地铁工程Near-miss知识库的逻辑结构.最后,采用具有成熟管理技术的关系数据库,将Near-miss知识存储于关系数据库表中,实现了知识库和关系数据库的耦合.一个完善的地铁工程Near-miss知识库的构建,将有助于促进地铁施工安全管理能力的提高,减少地铁事故的发生. 展开更多
关键词 地铁工程 near-MISS 框架表示 知识库 关系数据库
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基于Near-Miss的高速公路专项养护工程安全管理模式 被引量:9
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作者 田卫 李慧民 +1 位作者 闫瑞琦 胡云香 《西安建筑科技大学学报(自然科学版)》 CSCD 北大核心 2013年第4期548-553,558,共7页
随着高速公路专项养护工程项目的不断增多,工程施工中的安全问题也越来越突显.为了减少养护作业区事故的发生,提高专项养护工程的安全管理水平,通过借鉴Near-Miss管理理论,建立了基于Near-Miss的高速公路专项养护工程安全管理系统.在此... 随着高速公路专项养护工程项目的不断增多,工程施工中的安全问题也越来越突显.为了减少养护作业区事故的发生,提高专项养护工程的安全管理水平,通过借鉴Near-Miss管理理论,建立了基于Near-Miss的高速公路专项养护工程安全管理系统.在此基础上,论述了在专项养护工程的"四方管理"模式中实现Near-Miss安全管理的过程,形成了改进的高速公路专项养护工程安全管理模式.这种从"问题出发型"向"问题发现型"转变的管理模式,将有助于从根本上解决专项养护工程中的安全问题. 展开更多
关键词 专项养护工程 near-Miss管理 安全管理 “四方管理”模式
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Flow Field Improvement by Bowed Stator Stages in a Compressor with Different Axial Gaps Under Near Stall Condition 被引量:4
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作者 陆华伟 陈浮 +2 位作者 宋彦萍 万继林 王仲奇 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2008年第3期215-222,共8页
The outlet flow fields of a low-speed repeating-stage compressor with bowed stator stages are measured with five-hole probe under the near stall condition when the rotor/stator axial gap varies. The performances of th... The outlet flow fields of a low-speed repeating-stage compressor with bowed stator stages are measured with five-hole probe under the near stall condition when the rotor/stator axial gap varies. The performances of the straight stator stages are investigated and compared to those of the bowed stator stages. The results show that using bowed stator stages could alleviate the flow separation at both upper and low corners of the suction surface and the endwalls, and decrease the losses along the flow passage as well as the outlet flow angle. As the rotor/stator axial gap decreases, although the diffusion capacity of the compressor increases obviously, the outlet flow field in the straight stator stages deteriorates quickly. By contrast, little changes occur in the bowed stator stages, indicating that as the rotor/stator axial gap decreases, improved performance is achieved in the bowed stator stages. 展开更多
关键词 COMPRESSOR bowed stator rotor/stator axial gap near stall condition corner separation
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基于Near Miss的成山头水域交通冲突风险可视化 被引量:5
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作者 谭志荣 张球林 +1 位作者 王伟 范中洲 《中国航海》 CSCD 北大核心 2016年第4期43-46,107,共5页
针对成山头水域商船与渔船交通冲突频发的现状,对船舶交通管理系统(Vessel Traffic Service,VTS)存储的船舶全程航行动态大数据进行挖掘;在交通冲突和黑点理论的基础上,基于船舶会遇提出采用Near Miss分布来定量描述水域风险的方法。在A... 针对成山头水域商船与渔船交通冲突频发的现状,对船舶交通管理系统(Vessel Traffic Service,VTS)存储的船舶全程航行动态大数据进行挖掘;在交通冲突和黑点理论的基础上,基于船舶会遇提出采用Near Miss分布来定量描述水域风险的方法。在Atlas VTS的基础上二次开发基于Near Miss的分析软件,根据Near Miss的时空特征实现水域风险可视化。以成山头水域2013年典型时段的船舶交通流数据为例,对该水域商船与渔船交通冲突风险进行可视化分析。结果表明:基于Near Miss分布的水域风险可视化方法可定量挖掘水域交通冲突风险的时空特征,有助于优化监管措施以降低潜在水域风险。 展开更多
关键词 水路运输 交通冲突 near MISS 时空分布 风险可视化
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Near-crash事件中驾驶人行为特征分析 被引量:11
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作者 吕能超 任泽远 +1 位作者 段至诚 罗毅 《中国安全科学学报》 CAS CSCD 北大核心 2017年第6期19-24,共6页
为研究不同驾驶人在追尾事故中的驾驶行为特征,用Near-crash事件代替真实碰撞事件,选取一段城市快速道路开展实车试验。首先测试21名驾驶人实驾时的最大减速度、制动至最大减速度时间、平均减速度、碰撞时间倒数(TTCi)4个指标;然后用Mob... 为研究不同驾驶人在追尾事故中的驾驶行为特征,用Near-crash事件代替真实碰撞事件,选取一段城市快速道路开展实车试验。首先测试21名驾驶人实驾时的最大减速度、制动至最大减速度时间、平均减速度、碰撞时间倒数(TTCi)4个指标;然后用Mobileye等设备提取数据,得到不同性别、驾驶经验、驾驶风格的驾驶人指标因素;最后对数据进行方差分析。结果表明:Near-crash事件中,女性驾驶人平均减速度、最大减速度大于男性驾驶人,女性驾驶人更倾向于急刹车;经验影响驾驶人的平均减速度、最大减速度;熟练驾驶人制动到最大减速度时间长,制动过程更加平稳;激进型驾驶风格的驾驶人车头时距(THW)小于保守型驾驶人。 展开更多
关键词 near-crash事件 实车驾驶 驾驶行为 方差分析 碰撞时间倒数(TTCi)
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Application of Near-nature Management Theories in the Construction of Ecological Scenic Forest——With Shenzhen City as a Study Case 被引量:1
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作者 王旭 周光益 +1 位作者 李家湘 邱治军 《Journal of Landscape Research》 2010年第7期7-10,共4页
With the present unceasing development of science and society,ecological and social functions of forest have attracted more and more attention.This study with Shenzhen City as an example through elaborating the concep... With the present unceasing development of science and society,ecological and social functions of forest have attracted more and more attention.This study with Shenzhen City as an example through elaborating the concepts and principles of ecological scenic forest and near-nature management,and combining with the present construction of ecological scenic forest in Shenzhen City,specifically stated the requirements,principles and implementation measures of different aspects involving in the construction of ecological scenic forest in Shenzhen,such as site classification,tree species selection,logging operation,community construction,tending management and benefit monitoring,and further expounded the application of near-nature management theories in this field.It was also stressed that the nature should be utilized and respected,artificial forest should be reformed into near-nature scenic forest with richer and more stable structure as well as higher protective eco-functions,so as to provide theoretical basis for the construction of ecological scenic forest and enhance its positive role in the urban construction of Shenzhen. 展开更多
关键词 near-nature management ECOLOGICAL SCENIC FOREST Nature ECOLOGY
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赌博游戏中的near-miss效应 被引量:2
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作者 索涛 杨雁 +2 位作者 范增 王梦梦 赵国祥 《心理科学进展》 CSSCI CSCD 北大核心 2018年第9期1689-1699,共11页
near-miss效应是指在赌博中,与一般的输钱和赢钱相比,"几乎赢(near-miss)"的输钱会诱发个体更高的生理唤醒和更强的赌博动机,从而导致个体持续赌博的一种现象,是导致赌博成瘾的主要诱因之一。针对这种现象的研究范式大致有三... near-miss效应是指在赌博中,与一般的输钱和赢钱相比,"几乎赢(near-miss)"的输钱会诱发个体更高的生理唤醒和更强的赌博动机,从而导致个体持续赌博的一种现象,是导致赌博成瘾的主要诱因之一。针对这种现象的研究范式大致有三种:老虎机/类老虎机任务、轮盘任务和刮刮乐彩票任务。这种现象的理论解释目前主要有认知曲解假说、控制幻觉理论和受挫假说。near-miss效应的脑机制和病理研究才刚刚起步,所涉及到的脑功能区域主要包括脑岛、腹侧纹状体等。未来的研究应在near-miss效应发生机制的理论模型建构、研究范式多样化、研究技术多模态化、病理机制和临床干预等方面进一步展开。 展开更多
关键词 near-miss效应 认知曲解假说 控制幻觉理论 受挫假说 脑岛 腹侧纹状体
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NEAR(p)模型的参数估计 被引量:1
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作者 朱复康 王德辉 曹伟 《吉林大学学报(理学版)》 CAS CSCD 北大核心 2006年第6期851-856,共6页
分别用条件最小二乘、加权条件最小二乘和最大拟似然方法估计了平稳的NEAR(p)模型的参数.并讨论了这些估计量的渐近性质.通过数值模拟发现,当参数真值较小时,最大拟似然方法的估计效果较好;当参数真值较大时,加权条件最小二乘方法的估... 分别用条件最小二乘、加权条件最小二乘和最大拟似然方法估计了平稳的NEAR(p)模型的参数.并讨论了这些估计量的渐近性质.通过数值模拟发现,当参数真值较小时,最大拟似然方法的估计效果较好;当参数真值较大时,加权条件最小二乘方法的估计效果较好. 展开更多
关键词 near(p)模型 条件最小二乘估计 加权条件最小二乘估计 最大拟似然估计
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具有GARCH(near-IGRACH)-normal误差项时序的ADF单位根检验 被引量:2
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作者 鲜思东 彭作祥 《重庆工商大学学报(自然科学版)》 2007年第5期459-463,共5页
在有限样本情况下,随机模拟具有GARCH(near-IGRACH)-normal error的ADF单位根检验,分析了两种数据生成模型下不同显著水平对临界值的影响.结果表明:随着显著性水平值的下降,相应的临界值绝对值变大了,特别是使用Zρ检验统计量时,对应的s... 在有限样本情况下,随机模拟具有GARCH(near-IGRACH)-normal error的ADF单位根检验,分析了两种数据生成模型下不同显著水平对临界值的影响.结果表明:随着显著性水平值的下降,相应的临界值绝对值变大了,特别是使用Zρ检验统计量时,对应的size distortion越来越严重,对高频金融时序进行单位根检验时,选择Zρ或Zt统计量需要进行一个权衡. 展开更多
关键词 单位根过程 GARCH过程 near—IGRACH过程 size distortion ADF检验
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Spatial distribution of near-fault ground motion 被引量:2
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作者 LIU Qi-fang(刘启方) +3 位作者 YUAN Yi-fan(袁一凡) JIN Xing(金星) 《Acta Seismologica Sinica(English Edition)》 CSCD 2004年第2期200-210,共11页
Near-fault strong ground motion of strike-slip and dip-slip of vertical and inclined rectangular fault in half-space and layered half-space is analyzed by dislocation source model. The Fourier spectra ratio of ground ... Near-fault strong ground motion of strike-slip and dip-slip of vertical and inclined rectangular fault in half-space and layered half-space is analyzed by dislocation source model. The Fourier spectra ratio of ground motion is adopted to study the characteristics of near-fault ground motion. For both slip models, near-fault strong ground motion with high amplitude is located in a narrow belt area along the projection of the fault on the ground and mainly controlled by the sub-faults nearby. Directivity of strike-slip fault is more dominant in long period for components perpendicular to the fault, and more dominant in long period for components parallel to the fault for dip-slip fault. The deeper the location of the source is, the more slowly the amplitude of ground motion attenuates. There is obvious hanging wall effect in ground motion of inclined fault, and the spatial distribution of ground motion is asymmetric which coincides with observational data. Finally, a fitting function of spatial distribution for near-fault ground motion is proposed and compared with near source factors of the 1997 Uniform Building Code of USA. 展开更多
关键词 near-fault strong ground motion dislocation model DIRECTIVITY near source factor
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