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Pro/E Wild Fire中零件库的建立方法 被引量:5
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作者 石晶 焦洪宇 张涛 《机械设计与制造》 北大核心 2005年第5期137-138,共2页
以Pro/E Wild Fire软件为基础,详细地论述了零件库的建立方法,分析了每种方法的优缺点,提出了适用范围,使零件库的建立更加简单化,从而有效的提高了实体建模速度,缩短了设计周期。
关键词 PRO/ENGINEER wild Fire 族表 自定义特征 编程
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我国证券市场有效性的Wild Bootstrap方差比检验 被引量:17
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作者 刘维奇 史金凤 《统计研究》 CSSCI 北大核心 2006年第11期73-78,共6页
This paper introduces the theory of market efficiency simply and surveys various methods and results of week form market efficiency test of China.Then we test the sample and propose to test the week form market effici... This paper introduces the theory of market efficiency simply and surveys various methods and results of week form market efficiency test of China.Then we test the sample and propose to test the week form market efficiency test of China using the wild bootstrap variance ratio test which has been found to exhibit better small sample properties.The results are conducted with moving sub-sample windows and found that Shanghai market has been efficient of week form but Shenzhen market hasn’t been efficiency of week form. 展开更多
关键词 市场有效性 方差比检验 wild BOOTSTRAP方法
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WILD:基于加权信息损耗的离散化算法 被引量:8
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作者 李刚 李霁伦 童兆页 《南京大学学报(自然科学版)》 CAS CSCD 北大核心 2001年第2期148-153,共6页
现实应用中常常涉及许多连续的数值属性 ,而目前许多机器学习算法则要求所处理的属性具有离散值 .基于信息论的基本原理 ,提出一种新的有监督离散化算法WILD ,该算它可以看成是决策树离散化算法的一种扩充 ,其主要改进在于考虑区间内观... 现实应用中常常涉及许多连续的数值属性 ,而目前许多机器学习算法则要求所处理的属性具有离散值 .基于信息论的基本原理 ,提出一种新的有监督离散化算法WILD ,该算它可以看成是决策树离散化算法的一种扩充 ,其主要改进在于考虑区间内观测值出现的频度 ,采用加权信息损耗作为区间离散化的测度 ,以克服决策树算法离散不均衡的问题 .该算法非常自然地采用了自底向上的区间归并方案 ,可以同时归并多个相邻区间 ,有利于提高离散化算法的速度 .实验结果表明该算法能够提高机器学习算法的精度 . 展开更多
关键词 机器学习 离散化 加权信息损耗 wild 决策树 有监督算法
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基于Wild Bootstrap方差比检验的REITs市场有效性研究——以香港为例 被引量:3
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作者 张红 孙煦 《金融理论与实践》 北大核心 2015年第8期103-107,共5页
基于有效市场假说(EMH),使用Wild Bootstrap方差比检验法研究REITs市场的有效性。首先,阐述有效市场假说的基本原理,建立Wild Bootstrap方差比检验模型;之后,以香港为例,选取恒生REITs指数(HSRI)和恒生综合指数(HSCI),从纵、横向角度分... 基于有效市场假说(EMH),使用Wild Bootstrap方差比检验法研究REITs市场的有效性。首先,阐述有效市场假说的基本原理,建立Wild Bootstrap方差比检验模型;之后,以香港为例,选取恒生REITs指数(HSRI)和恒生综合指数(HSCI),从纵、横向角度分别进行总体和滑动方差比检验;最后,根据检验结果和实际情况判断REITs市场的有效性,得出研究结论和投资建议。在REITs市场有效性研究中引入了Wild Bootstrap方差比检验法,为相关研究提供了新的方法与研究视角。研究表明,香港REITs市场尚未达到弱式有效,市场有效性有待加强。 展开更多
关键词 REITS 市场有效性 方差比检验 wild BOOTSTRAP方法
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线性回归M估计量的Wild Bootstrap方法研究 被引量:1
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作者 祝金甫 汤伟 冯兴东 《统计研究》 CSSCI 北大核心 2015年第8期99-103,共5页
Wild Bootstrap是一种适用于回归方程中存在异方差时的再取样方法。本文通过线性回归Huber估计量的模拟研究,比较了不同的bootstrap方法,并验证了wild bootstrap方法在有限样本下的有效性。通过运用一种简单有限样本统计量对wild bootst... Wild Bootstrap是一种适用于回归方程中存在异方差时的再取样方法。本文通过线性回归Huber估计量的模拟研究,比较了不同的bootstrap方法,并验证了wild bootstrap方法在有限样本下的有效性。通过运用一种简单有限样本统计量对wild bootstrap加以修正,对于存在异方差性且基于固定设计的回归模型而言,wild bootstrap成为首选的重复抽样法。 展开更多
关键词 Bahadur表达式 异方差误差 M估计量 wild BOOTSTRAP
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我国创业板市场弱式有效性的实证分析——基于Wild Bootstrap方差比检验 被引量:4
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作者 王红 陈帅 《商业时代》 北大核心 2014年第32期96-99,共4页
本文根据市场有效性假说,采用Wild Bootstrap方差比方法,基于创业板价格指数(399006)和创业板综合指数(399102),对我国创业板市场的有效性进行研究。研究结果表明,我国创业板市场具有弱式有效性。
关键词 我国创业板市场 弱式有效性 wild Bootstrap方差比检验
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论wild rice不一定指野生稻
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作者 阿新祥 熊华斌 +5 位作者 徐福荣 汤翠凤 余腾琼 樊传章 胡意良 戴陆园 《西南农业学报》 CSCD 2007年第6期1394-1398,共5页
野生稻,英文译为wild rice,但笔者在查阅有关野生稻(wild rice)的英文文献时发现,wild rice除指代禾本科稻属中的野生稻之外;还有文献指代的是禾本科菰属的菰米。因此,本文分两部分阐述,野生稻与菰的比较、wild rice不一定指野生稻,为... 野生稻,英文译为wild rice,但笔者在查阅有关野生稻(wild rice)的英文文献时发现,wild rice除指代禾本科稻属中的野生稻之外;还有文献指代的是禾本科菰属的菰米。因此,本文分两部分阐述,野生稻与菰的比较、wild rice不一定指野生稻,为后人查阅wild rice时辨别菰或野生稻提供有效的帮助。 展开更多
关键词 wild RICE 野生稻
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tudies on Annual Wild Soybeans 被引量:2
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作者 Zhang Guodong 《Journal of Northeast Agricultural University(English Edition)》 CAS 1994年第1期9-19,共11页
关键词 wild tudies on Annual wild Soybeans
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STAR模型框架下的wild bootstrap单位根检验
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作者 欧阳敏华 《统计与决策》 CSSCI 北大核心 2016年第12期62-65,共4页
考虑随机误差项存在异方差的情形,文章建立了STAR模型框架下的wild bootstrap单位根检验策略。Monte Carlo模拟研究的结果表明,若时间序列存在GARCH异方差,KSS非线性单位根检验统计量的检验水平扭曲程度要远高于线性ADF统计量,且GARCH... 考虑随机误差项存在异方差的情形,文章建立了STAR模型框架下的wild bootstrap单位根检验策略。Monte Carlo模拟研究的结果表明,若时间序列存在GARCH异方差,KSS非线性单位根检验统计量的检验水平扭曲程度要远高于线性ADF统计量,且GARCH特征越明显,扭曲程度越高。无论GARCH特征明显与否,wild bootstrap单位根检验方法都不存在检验水平扭曲,且具有理想的检验势。 展开更多
关键词 STAR模型 单位根 KSS统计量 wild BOOTSTRAP
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Exploitation of Wild Flowers and the Sustainable Development of Flowers Industry in China 被引量:4
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作者 HONG Li PANG Songling ZHUO Lihuan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2008年第2期76-79,共4页
This article introduced the new methods on the research of the wild flowers and plants idioplasmic resources, elaborated the introduction and domestication and exploitation of wild flowers and plants idioplasmatic res... This article introduced the new methods on the research of the wild flowers and plants idioplasmic resources, elaborated the introduction and domestication and exploitation of wild flowers and plants idioplasmatic resources and the sustainable development of flowers and plants industry in China, and put forward some proposals on the existing question and the prospects for the development. 展开更多
关键词 wild flowers and plants development and utilization flowers and plants industry sustainable development
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双二次域的Tame核和Wild核
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作者 孙爱玲 《河海大学学报(自然科学版)》 CAS CSCD 1999年第5期78-79,共2页
设F= Q( d , - 1) 为双二次域,K2 OF 和W( F) 分别是F的Tame 核和Wild 核.本文决定了K2 OF/ W( F) 的结构.
关键词 Tame核 wild 素理想 双二次域
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Protection and Quality Control of Wild Chinese Herbal Medicine Resources in Nature Reserves by Taking Longyuwan Scenic Spot Within Funiu Mountain Nature Reserve as an Example 被引量:1
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作者 Wang Shao-hui Liu Meng-na +4 位作者 Wang Xu Zhang Ya-chen Han Yi-wen Zhang Ce Liu Tong-xiang 《Journal of Northeast Agricultural University(English Edition)》 CAS 2016年第3期90-96,共7页
This paper discussed how to protect and control the quality of wild Chinese herbal medicine resources in nature reserves by taking Longyuwan National Forest Park within Funiu Mountain Nature Reserve as an example. Thr... This paper discussed how to protect and control the quality of wild Chinese herbal medicine resources in nature reserves by taking Longyuwan National Forest Park within Funiu Mountain Nature Reserve as an example. Through the combination of three methods including literature review, visiting and investigational studies, and field surveys, the data of investigation, collection and collation were analyzed. According to data of surveys, collection and collation, problems related to the protection of wild Chinese herbal medicine resources faced by Longyuwan Scenic Spot within Funiu Mountain Nature Reserve were also analyzed and protection strategies and quality control of wild Chinese herbal medicine resources in this nature reserve were discussed. It was expected that the results would provide important scientific references for the sustainable development, protection and quality control of wild Chinese herbal medicine resources within nature reserves. 展开更多
关键词 nature reserve wild Chinese herbal medicine resource PROTECTION quality control
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极小Wild系统箭图代数的Hochschild上同调群
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作者 张丹丹 《科学技术与工程》 2010年第35期8645-8648,8652,共5页
设Γj=kQ/Ij是极小Wild表示型系统箭图代数,基于Bardzell的方法构造了Γj的极小投射双模分解,并由此清晰地计算了Γj的各阶Hochschild上同调群的维数。
关键词 系统箭图 极小wild表示型 极小投射双模分解 HOCHSCHILD上同调群
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谱检验的Wild Bootstrap方法
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作者 王明进 《统计研究》 CSSCI 北大核心 2008年第6期83-87,共5页
本文考察了基于谱估计的拟合优度检验在判断时间序列鞅差性质方面的应用,提出了利用Wild Bootstrap来近似该类检验统计量渐近分布的方法,通过模拟试验揭示出新的方法改进了检验的水平并提高了其功效,最后比较了不同方法在分析实际金融... 本文考察了基于谱估计的拟合优度检验在判断时间序列鞅差性质方面的应用,提出了利用Wild Bootstrap来近似该类检验统计量渐近分布的方法,通过模拟试验揭示出新的方法改进了检验的水平并提高了其功效,最后比较了不同方法在分析实际金融数据时的不同效果。 展开更多
关键词 时间序列 谱分布 拟合优度 wild BOOTSTRAP 市场有效
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Identification of Toll-like Receptor (TLR) 4 Gene in Wild Boar
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作者 Du Xin Zhuo Jian-shu +3 位作者 Jing Xiao-yan Wang Chao Liu Ying-zi Yang Xiu-qin 《Journal of Northeast Agricultural University(English Edition)》 CAS 2017年第3期68-74,共7页
Toll-like receptor (TLR) 4 plays an important role in the innate immune system and has been involved in resistance/ susceptibility to a number of diseases as revealed by studies in human and other domestic animals. ... Toll-like receptor (TLR) 4 plays an important role in the innate immune system and has been involved in resistance/ susceptibility to a number of diseases as revealed by studies in human and other domestic animals. Wild boar survives in natural environment without artificial interference and may be different from domestic pig in innate immune system. Here, the complete coding sequence of TLR4 and TLR4A was cloned in wild boar, and two other alternative splicing variants, TLR4B and TLR4C, were obtained. Compared to the counterpart from domestic pig (GcnBank No. AJ628065), there were five SNPs, c.510T〉C, c.960A〉G, c.962A〉G, c.1605T〉G and c.1824A〉G, in the coding sequence of wild boar TLR4A gene. TLR4 gene was expressed in all the tissues from wild boar studied with the most abundance in spleen tissue, and mRNA level was significantly lower in spleen from wild boar than that from Min pig. The allele distribution was significantly different at polymorphic loci c.962G〉A and c.1027C〉A (p〈0.01) between wild boar and Min pig. The results would contribute to understand the innate immune system in wild boar. 展开更多
关键词 wild boar TLR4 transcript variant EXPRESSION POLYMORPHISM
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Risk Analysis of Wild Birds in Spread of Highly Pathogenic Avian Influenza
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作者 Ian Robertson 《Journal of Northeast Agricultural University(English Edition)》 CAS 2010年第1期77-83,共7页
Outbreaks of highly pathogenic avian influenza (HPAI) H5N 1 have taken place in 15 countries in Asia, Europe and Africa since 2003, and have caused great economic losses. Much likelihood has been considered as risk ... Outbreaks of highly pathogenic avian influenza (HPAI) H5N 1 have taken place in 15 countries in Asia, Europe and Africa since 2003, and have caused great economic losses. Much likelihood has been considered as risk factors, of which wild birds are attributed as one of the main factors. This is related to the environmental deterioration in the wetland and expanse of human's activities in production. The risk analysis in this paper only focused on the effect of wild birds to HPAI, and confirmed the high risk of wild birds in the spread of AIVs. 展开更多
关键词 avian influenza HPAI H5N1 wild bird risk analysis
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Genetics Research and Advance on Development and Utilization of Wild Boars
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作者 LIU Chunlong LIU Di LI Zhongqiu 《Journal of Northeast Agricultural University(English Edition)》 CAS 2011年第3期83-87,共5页
Wild boar is one of the most important beast resources. It plays an important role in the maintenance of biological diversity. The genetic resources of wild boar can not only protect the genetic resources, but also im... Wild boar is one of the most important beast resources. It plays an important role in the maintenance of biological diversity. The genetic resources of wild boar can not only protect the genetic resources, but also improve the formation of new breeds in pigs. This paper summarized the advance on the main biological characteristics of wild boars, evolutionary origin between wild boars and domesticated pigs, and development and utilization of wild boars aimed to provide further insight into wild boar's genetic research and its resource protection. 展开更多
关键词 wild boar biological characteristics GENETICS development and utilization
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Inside and Outside: A Spatial Perspective on Oscar Wilde’s Salomé
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作者 YAO Yijie CHEN Li 《北京第二外国语学院学报》 2016年第5期145-145,共1页
As the exponent of the aesthetic movement, Oscar Wilde has paidalmost excessive attention to the aestheticization of indoor spaces. For him, thehumanly-decorated house offers a sense of order and reason, which has, to... As the exponent of the aesthetic movement, Oscar Wilde has paidalmost excessive attention to the aestheticization of indoor spaces. For him, thehumanly-decorated house offers a sense of order and reason, which has, to a largeextent, assisted the formation of man’s ego and identity, while the outside world,filled with horror, confusion and anxiety, is always associated with the loss ofsubjectivity and individuality. His topophilia is well manifested in some of his morerenowned works, while its fullest expression can no doubt be found in The Decay ofLying, where he would complain in Vivian’s voice how “one becomes abstract andimpersonal” out of doors. In his one-act tragedy Salomé, however, the event whichwas traditionally believed to take place within Herod’s palace was deliberately setoutside the doors. To a certain degree, this arrangement has set the tone for the wholetragedy. Through the employment of the outdoor spaces and the deliberate confusionof the Inside with the Outside, Oscar Wilde has successfully created an atmosphere ofmadness, absurdity and horror that has haunted Salomé from the very beginning: theoutdoor spaces, in facilitating the identification of Salome with the image of Maenad,give the play a touch of madness; Salome’s deliberate attempts at confusing the Insidewith the Outside, principally motivated by the male gaze that permeates the indoorspaces and costs Salome her subjectivity, was plagued with futility and fruitlessness,from whence came the horror of homelessness that has consummated her tragedy. 展开更多
关键词 OSCAR wilde Salomé SPATIAL theory AESTHETICISM SUBJECTIVITY
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Growth and Development of The Kunlun Type of Wild Yak
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作者 李吉叶 《中国草食动物》 2005年第z2期227-228,共2页
The observation of body height and weight of 10 captured wild yak shows the body height and weight of the wild yak at three and four months old were similar with that of domestic yak. At their 24 months old, the body ... The observation of body height and weight of 10 captured wild yak shows the body height and weight of the wild yak at three and four months old were similar with that of domestic yak. At their 24 months old, the body height and weight were higher by 26.9 % and 62.5 % than that of the domestic ones. The results indicate that, once adapted to the half-shed and half-grazing conditions, the tamed Kunlun type of wild yak with superior genetics would grow and develop faster than the domestic yak at elder ages. 展开更多
关键词 KUNLUN TYPE wild YAK taming GROWTH DEVELOPMENT
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Construction of Databank for Genetic Resource of Wild Yak in China
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作者 杨博辉 《中国草食动物》 2005年第z2期235-238,共4页
In the paper, comprehensively explaining structure , function and main contents of databank for genetic resource of wild Yak in China.
关键词 wild YAK databank GENETIC RESOURCE
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