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量测化普通数码影像的随点生成核线匹配方法
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作者 陈新玺 李浩 +1 位作者 顾君晖 杨立君 《测绘科学》 CSCD 北大核心 2011年第3期114-115,138,共3页
基于普通数码影像的近景摄影测量算法成为目前摄影测量研究的热点,本文针对量测化普通数码影像的核线相关匹配特性,提出了一种随点生成核线匹配算法。实验数据表明该算法可在量测化普通数码影像上进行一维匹配,很好地提高了匹配精度和... 基于普通数码影像的近景摄影测量算法成为目前摄影测量研究的热点,本文针对量测化普通数码影像的核线相关匹配特性,提出了一种随点生成核线匹配算法。实验数据表明该算法可在量测化普通数码影像上进行一维匹配,很好地提高了匹配精度和效率。 展开更多
关键词 普通数码影像 量测化 随点生成核线 匹配
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如何求动点的轨迹方程 被引量:1
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作者 舒振武 《数学教学通讯(教师阅读)》 2010年第8期52-53,58,共3页
本文叙述了求动点轨迹的一般步骤;盘点了求动点轨迹的一般方法:直译法、点随点动法、定义法与参数法.阐述了圆锥曲线在实际问题中的应用.
关键词 几何条件坐标化 直译法 随点动法 参数法 轨迹方程应用题
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潮剧伴奏之我见
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作者 方俊荣 《戏剧之家》 2015年第13期8-8,共1页
潮剧伴奏是潮剧音乐的主要组成部分,合格的伴奏人员必须有扎实的基本功、对剧种曲牌的深刻理解和丰富的舞台经验。
关键词 基本功 七律 三分唱 七分伴 板式 曲牌 锣经 随点 半畔莲
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SSABC:a super-peer selection algorithm based on capacity
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作者 赵生慧 钱宁 +1 位作者 吴国新 陈桂林 《Journal of Southeast University(English Edition)》 EI CAS 2008年第4期444-449,共6页
Combining the characteristics of peer-to-peer (P2P) and grid, a super-peer selection algorithm--SSABC is presented in the distributed network merging P2P and grid. The algorithm computes nodes capacities using their... Combining the characteristics of peer-to-peer (P2P) and grid, a super-peer selection algorithm--SSABC is presented in the distributed network merging P2P and grid. The algorithm computes nodes capacities using their resource properties provided by a grid monitoring and discovery system, such as available bandwidth, free CPU and idle memory, as well as the number of current connections and online time. when a new node joins the network and the super-peers are all saturated, it should select a new super-peer from the new node or joined nodes with the highest capacity. By theoretical analyses and simulation experiments, it is shown that super-peers selected by capacity can achieve higher query success rates and shorten the average hop count when compared with super-peers selected randomly, and they can also balance the network load when all super-peers are saturated. When the number of total nodes changes, the conclusion is still valid, which explains that the algorithm SSABC is feasible and stable. 展开更多
关键词 peer to peer (P2P) GRID SUPER-PEER capacity selection: random selection
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A method of automatic plane detection without random search
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作者 李中科 杨晓辉 吴乐南 《Journal of Southeast University(English Edition)》 EI CAS 2003年第3期216-220,共5页
Plane detection is a prerequisite for many computer vision tasks. This paper proposes a new method which can automatically detect planes from two projective images. Firstly, we modify Scott’s feature point matching m... Plane detection is a prerequisite for many computer vision tasks. This paper proposes a new method which can automatically detect planes from two projective images. Firstly, we modify Scott’s feature point matching method by post-processing its result with the concept of similarity, and then get the lines matching according to feature points matching based on the approximate invariance of the features’ distribution between two images. Finally, we group all feature points into subsets in terms of their geometric relations with feature lines as initial sets to estimate homography rather than by a random search strategy (like RANSAC) as in most existing methods. The proposed method is especially suitable to detecting planes in man-made scenes. This method is validated on real images. 展开更多
关键词 plane detection feature matching plane homography computer vision
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Reliability Analysis of Repairable Systems Using Stochastic Point Processes 被引量:1
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作者 谭芙蓉 江志斌 白同朔 《Journal of Shanghai Jiaotong university(Science)》 EI 2008年第3期366-369,共4页
In order to analyze the failure data from repairable systems, the homogeneous Poisson process (HPP) is usually used. In general, HPP cannot be applied to analyze the entire life cycle of a complex, re-pairable system ... In order to analyze the failure data from repairable systems, the homogeneous Poisson process (HPP) is usually used. In general, HPP cannot be applied to analyze the entire life cycle of a complex, re-pairable system because the rate of occurrence of failures (ROCOF) of the system changes over time rather than remains stable. However, from a practical point of view, it is always preferred to apply the simplest method to address problems and to obtain useful practical results. Therefore, we attempted to use the HPP model to analyze the failure data from real repairable systems. A graphic method and the Laplace test were also used in the analysis. Results of numerical applications show that the HPP model may be a useful tool for the entire life cycle of repairable systems. 展开更多
关键词 repairable systems reliability analysis homogeneous Poisson process (HPP) rate of occurrence of failures (ROCOF) stochastic point process Laplace test
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Random vibration analysis of switching apparatus based on Monte Carlo method 被引量:6
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作者 ZHAI Guo-fu CHEN Yang-hua REN Wan-bin 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第3期422-425,共4页
The performance in vibration environment of switching apparatus containing mechanical contact is an important element when judging the apparatus’s reliability. A piecewise linear two-degrees-of-freedom mathematical m... The performance in vibration environment of switching apparatus containing mechanical contact is an important element when judging the apparatus’s reliability. A piecewise linear two-degrees-of-freedom mathematical model considering contact loss was built in this work, and the vibration performance of the model under random external Gaussian white noise excitation was investigated by using Monte Carlo simulation in Matlab/Simulink. Simulation showed that the spectral content and statistical characters of the contact force coincided strongly with reality. The random vibration character of the contact system was solved using time (numerical) domain simulation in this paper. Conclusions reached here are of great importance for reliability design of switching apparatus. 展开更多
关键词 Contact system Random vibration Monte Carlo simulation MATLAB/SIMULINK
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Single Point Positioning with Sequential Least-Squares Filter and Estimated Real-Time Stochastic Model 被引量:7
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作者 WU Yun GUO Jiming 《Geo-Spatial Information Science》 2008年第1期13-16,共4页
To obtain higher accurate position estimates, the stochastic model is estimated by using residual of observations, hence, the stochastic model describes the noise and bias in measurements more realistically. By using ... To obtain higher accurate position estimates, the stochastic model is estimated by using residual of observations, hence, the stochastic model describes the noise and bias in measurements more realistically. By using GPS data and broadcast ephemeris, the numerical results indicating the accurate position estimates at sub-meter level are obtainable. 展开更多
关键词 GPS single point positioning functional model stochastic model sequential least-square filter
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A Time-dependent Stochastic Grassland Fire Ignition Probability Model for Hulun Buir Grassland of China 被引量:5
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作者 GUO Zhixing FANG Weihua +1 位作者 TAN Jun SHI Xianwu 《Chinese Geographical Science》 SCIE CSCD 2013年第4期445-459,共15页
Grassland fire is one of the most important disturbance factors in the natural ecosystems.This paper focuses on the spatial distribution of long-term grassland fire patterns in the Hulun Buir Grassland located in the ... Grassland fire is one of the most important disturbance factors in the natural ecosystems.This paper focuses on the spatial distribution of long-term grassland fire patterns in the Hulun Buir Grassland located in the northeast of Inner Mongolia Autonomous Region in China.The density or ratio of ignition can reflect the relationship between grassland fire and different ignition factors.Based on the relationship between the density or ratio of ignition in different range of each ignition factor and grassland fire events,an ignition probability model was developed by using binary logistic regression function and its overall accuracy averaged up to 81.7%.Meanwhile it was found that daily relative humidity,daily temperature,elevation,vegetation type,distance to county-level road,distance to town are more important determinants of spatial distribution of fire ignitions.Using Monte Carlo method,we developed a time-dependent stochastic ignition probability model based on the distribution of inter-annual daily relative humidity and daily temperature.Through this model,it is possible to estimate the spatial patterns of ignition probability for grassland fire,which will be helpful to the quantitative evaluation of grassland fire risk and its management in the future. 展开更多
关键词 grassland fire binary logistic regression GIS spatial analysis ignition probability Monte Carlo method
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Transumbilical laparoendoscopic single-site surgery(LESS) partial nephrectomy:a median follow-up of 2 years
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作者 Wang Linhui Wu Zhenjie Liu Bing Yang Qing Xiao Liang Sun Yinghao 《Journal of Medical Colleges of PLA(China)》 CAS 2011年第6期305-315,共11页
Objective:Nephron-sparing surgery(NSS) for small renal masses offers a similar functional and oncological outcome to that of radical surgery.Laparoendoscopic single-site surgery(LESS) emerges as an advanced alternativ... Objective:Nephron-sparing surgery(NSS) for small renal masses offers a similar functional and oncological outcome to that of radical surgery.Laparoendoscopic single-site surgery(LESS) emerges as an advanced alternative for reduced invasiveness and improves cosmesis;LESS is developing quickly and its indications have been expanded,but still in its infancy.The aim of this paper is to report our preliminary experience in transumbilical LESS partial nephrectomy(LESS-PN),so as to assess its utility, safety and efficacy.Methods:From August 2009 to October 2010,3 patients underwent transumbilical LESS-PN via a novel multi-channel TriPort by a single experienced urologist in our institution.Patient demographics,perioperative and follow-up data were prospectively collected and analyzed.Results:All the three procedures were successfully completed.A 5-mm ancillary trocar was utilized in all 3 cases.The mean operative duration was 226.3(210-254 min) with an estimated blood loss of 56.7 ml (20-100 ml).Mean warm ischemia time was 35.7 min(19-48 min).One patient was transfused due to postoperative bleeding. The recovery was uneventful and mean length of postoperative stay was 13 days(12-14 days).At the latest follow-up,all patients remained symptom-free and had normal renal function without evidence of recurrence,and they were delighted for a hidden transumbilical scar.Conclusion:Transumbilical LESS-PN is a feasible and safe procedure albeit extremely technically challenging.Surgical outcomes at a median follow-up of 2 years are promising,while currently it should be reserved for highly selected patients with favorable tumor anatomy and performed by a very experienced laparoscopic surgeon. 展开更多
关键词 Partial nephrectomy Laparoendoscopic single-site surgery Nephron sparing surgery
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A Novel Method for Banks to Monitor the Cumulative Loss Due to Defaults
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作者 KSS lyer 《Journal of Mathematics and System Science》 2014年第4期244-250,共7页
Banking institutions all over the world face significant challenge due to the cumulative loss due to defaults of borrowers of different types of loans. The cumulative default loss built up over a period of time could ... Banking institutions all over the world face significant challenge due to the cumulative loss due to defaults of borrowers of different types of loans. The cumulative default loss built up over a period of time could wipe out the capital cushion of the banks. The aim of this paper is to help the banks to forecast the cumulative loss and its volatility. Defaulting amounts are random and defaults occur at random instants of time. A non Markovian time dependent random point process is used to model the cumulative loss. The expected loss and volatility are evaluated analytically. They are functions of probability of default, probability of loss amount, recovery rate and time. Probability of default being the important contributor is evaluated using Hidden Markov modeling. Numerical results obtained validate the model. 展开更多
关键词 Random point process expected cumulative loss non Markovian hidden Markov model
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On the Cluster Set C [S_n/(2nφ(n))^(1/2)] in 2-type Banach Space
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作者 王新全 田长安 杨长森 《Chinese Quarterly Journal of Mathematics》 CSCD 1999年第2期88-93, ,共6页
Suppose {X,X n,n≥1} are the i.i.d. random variables with values in 2 type Banach space B,S n=∑nk=1X k,φ(x) is a increasing function on [0,+∞), φ(x)→+∞, and φ(x)x is no increasing; then we point out that the cl... Suppose {X,X n,n≥1} are the i.i.d. random variables with values in 2 type Banach space B,S n=∑nk=1X k,φ(x) is a increasing function on [0,+∞), φ(x)→+∞, and φ(x)x is no increasing; then we point out that the cluster set CS n2nφ(n) is ρK, where ρ= lim L 2nφ(n)<+∞, ∫ ∞e -ρ 2φ(x) 1xd x=+∞,X∈WM 2 0, and E‖X‖ 2φ(‖X‖)<+∞. 展开更多
关键词 type space INDEPENDENCE CLUSTER
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Available capacity and robust wireless mesh connectivity of TDD-based networks
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作者 宋甲英 Li +2 位作者 Xu Zhong Zhangdui 《High Technology Letters》 EI CAS 2011年第1期80-85,共6页
This paper addresses the available capacity and robust connectivity of time division duplex based wireless mesh networks (TDD-based WMNs). A stochastic model is presented for TDD-based WMNs. Considering the paramete... This paper addresses the available capacity and robust connectivity of time division duplex based wireless mesh networks (TDD-based WMNs). A stochastic model is presented for TDD-based WMNs. Considering the parameters that affect the network performance like ratio of control slots number to data slots number, collision probability, node density and average hopcounts, the availa- ble capacity for each node is inferred. Meanwhile, the order of transmission range for robust connec- tivity of large scale WMNs is derived. With the stochastic model and inferred available capacity per node, the performance of TDD-based WMNs using IEEE 802.16 standard is analyzed under various conditions. Simulation results indicate that the available capacity of IEEE 802.16-based TDD-based WMNs and the theoretical result have the same increasing and decreasing trend as the node density increases. Simulation results also illustrate the optimal value of the ratio of control slots number to data slots number that maximizes the available capacity. 展开更多
关键词 wireless mesh networks (WMNs) TDD/TDMA performance analysis available capacity robust connectivity
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Two-stage stochastic approach for spinning reserve allocation in dynamic economic dispatch 被引量:1
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作者 杨明 张利 +1 位作者 韩学山 程凤璐 《Journal of Central South University》 SCIE EI CAS 2014年第2期577-586,共10页
A novel approach was proposed to allocate spinning reserve for dynamic economic dispatch.The proposed approach set up a two-stage stochastic programming model to allocate reserve.The model was solved using a decompose... A novel approach was proposed to allocate spinning reserve for dynamic economic dispatch.The proposed approach set up a two-stage stochastic programming model to allocate reserve.The model was solved using a decomposed algorithm based on Benders' decomposition.The model and the algorithm were applied to a simple 3-node system and an actual 445-node system for verification,respectively.Test results show that the model can save 84.5 US $ cost for the testing three-node system,and the algorithm can solve the model for 445-node system within 5 min.The test results also illustrate that the proposed approach is efficient and suitable for large system calculation. 展开更多
关键词 power system dynamic economic dispatch spinning reserve response risk two-stage stochastic programming Benders' decomposition
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P53 gene could be a new effective therapeutic target in triple-negative breast cancer: a Meta-analysis
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作者 Fang Guo Zhaozhe Liu +1 位作者 Hongbo Liu Xiaodong Xie 《The Chinese-German Journal of Clinical Oncology》 CAS 2013年第8期369-373,共5页
Objective: The aim of this study was to explore the relationship between p53 gene and triple-negative breast cancer (TNBC), and determine that whether p53 gene could be a new effective therapeutic target. Methods:... Objective: The aim of this study was to explore the relationship between p53 gene and triple-negative breast cancer (TNBC), and determine that whether p53 gene could be a new effective therapeutic target. Methods: We identified studies with quantitative data on the relation of p53 gene and TNBC through searching 12 databases online (Oct. 1999-Oct. 2012) and reviewing the references, which were written in English or Chinese. Summary estimates of odds ratio (OR) was calculated using the fixed-effects model or the random-effects model as appropriate. Results: We identified 12 eligible stud- ies with 1532 cases of TNBC patients and 6329 controls of non-TNBC patients. The test for homogeneity resulted in X^2 = 200.16 (P 〈 0.05), it showed significant heterogeneity so that a random effect model was applied. Our results showed that the expression of p53 gene could be much stronger in TNBC group than that in non-TNBC group [OR = 2.10, 95% confidence interval (CI) = 1.21-3.65]. In ethnicity-subgroup analysis, we found that in Caucasian group, the expression of p53 gene were stronger in TNBC group (OR = 2.60, 95% CI = 1.21-5.57), but there was no statistical significance in Asian group (OR = 1.69, 95% CI = 0.83-3.45). Conclusion: P53 gene could be an effective predictor and a good therapeutic target for TNBC patients in the future, especially in Caucasian. Further researches focusing on p53 gene would gain a breakthrough in the treatment of TNBC. 展开更多
关键词 P53 triple negative breast cancer (TNBC) META-ANALYSIS TARGETS
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Surgical Resection of Sternal Tumors and Reconstruction with Titanium Mesh 被引量:1
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作者 Hong-sheng Liu Ying-zhi Qin Shan-qing Li Li Li Yu-shang Cui Zhi-yong Zhang 《Chinese Medical Sciences Journal》 CAS CSCD 2011年第4期237-240,共4页
Objective To evaluate the use of titanium mesh reconstruction after sternal tumor resection. Methods From January 2007 to January 2011, 14 patients with sternal tumors were admitted into Peking Union Medical Hospital.... Objective To evaluate the use of titanium mesh reconstruction after sternal tumor resection. Methods From January 2007 to January 2011, 14 patients with sternal tumors were admitted into Peking Union Medical Hospital. The clinical characteristics, surgical resection, and technique of reconstruction were reviewed. Results Of the 14 patients, 3 had a metastatic sternal tumor, the primary sites of which were as follows: hepatic carcinoma in one case (metastasis 19 years after operation), breast carcinoma in another case (metastasis 5 years after operation), and renal carcinoma in the other case (found simultaneously). Two patients showed local involvement of the sternum: 1 had thymic carcinoma, and the other had myofibrosarcoma. The remaining 9 patients had primary tumors: 4 were osteochondroma, 3 chondrosarcoma, 1 eosinophilic granuloma, 1 non-Hodgekin's lymphoma. En bloc resection of the sternal tumor was performed in all the 14 patients. The defect was repaired with the titanium mesh adjusted to the shape of the defect and fixed with the stainless steel wire. Eleven patients were followed up for a period from 2 months to 4 years, during which no translocation or broken of the titanium mesh was observed. Conclusions Radical en bloc excision remains the treatment of choice for sternal tumors. Sternum defect reconstruction using titanium mesh as a rigid replacement proves appropriate and effective. 展开更多
关键词 sternal tumor en bloc resection sternal reconstruction rigid prosthetic replacement titanium mesh
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Traffic assignment problem under tradable credit scheme in a bi-modal stochastic transportation network: A cumulative prospect theory approach 被引量:2
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作者 HAN Fei ZHAO Xiang-mo CHENG Lin 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第1期180-197,共18页
The traffic equilibrium assignment problem under tradable credit scheme(TCS) in a bi-modal stochastic transportation network is investigated in this paper. To describe traveler’s risk-taking behaviors under uncertain... The traffic equilibrium assignment problem under tradable credit scheme(TCS) in a bi-modal stochastic transportation network is investigated in this paper. To describe traveler’s risk-taking behaviors under uncertainty, the cumulative prospect theory(CPT) is adopted. Travelers are assumed to choose the paths with the minimum perceived generalized path costs, consisting of time prospect value(PV) and monetary cost. At equilibrium with a given TCS, the endogenous reference points and credit price remain constant, and are consistent with the equilibrium flow pattern and the corresponding travel time distributions of road sub-network. To describe such an equilibrium state, the CPT-based stochastic user equilibrium(SUE) conditions can be formulated under TCS. An equivalent variational inequality(VI) model embedding a parameterized fixed point(FP) model is then established, with its properties analyzed theoretically. A heuristic solution algorithm is developed to solve the model, which contains two-layer iterations. The outer iteration is a bisection-based contraction method to find the equilibrium credit price, and the inner iteration is essentially the method of successive averages(MSA) to determine the corresponding CPT-based SUE network flow pattern. Numerical experiments are provided to validate the model and algorithm. 展开更多
关键词 tradable credit scheme cumulative prospect theory endogenous reference points generalized path costs stochastic user equilibrium variational inequality model heuristic solution algorithm
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The Multivariate Saddlepoint Approximation to the Distribution of Estimators: A General Approach
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作者 Juan Carlos Abril Maria de las Mercedes Abril Carlos I. Martinez 《Journal of Mathematics and System Science》 2016年第2期53-59,共7页
We develop the theory of multivariate saddlepoint approximations. Our treatment differs from the one in Barndorff-Nielsen and Cox (1979, equation (4.7)) in two aspects: 1) our results are satisfied for random ve... We develop the theory of multivariate saddlepoint approximations. Our treatment differs from the one in Barndorff-Nielsen and Cox (1979, equation (4.7)) in two aspects: 1) our results are satisfied for random vectors that are not necessarily sums of independent and identically distributed random vectors, and 2) we consider that the sample is taken from any distribution, not necessarily a member of the exponential family of densities. We also show the relationship with the corresponding multivariate Edgeworth approximations whose general treatment was developed by Durbin in 1980, emphasizing that the basic assumptions that support the validity of both approaches are essentially similar. 展开更多
关键词 Approximate distributions Asymptotic expansions Edgeworth approximations Saddlepoint approximations.
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OUTLIER TEST IN RANDOMIZED LINEAR MODEL 被引量:2
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作者 XIANGLIMING SHILEI 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1994年第1期65-75,共11页
In this papert we give an approach for detecting one or more outliers inrandomized linear model.The likelihood ratio test statistic and its distributions underthe null hypothesis and the alternative hypothesis are giv... In this papert we give an approach for detecting one or more outliers inrandomized linear model.The likelihood ratio test statistic and its distributions underthe null hypothesis and the alternative hypothesis are given. Furthermore,the robustnessof the test statistic in a certain sense is proved. Finally,the optimality properties of thetest are derived. 展开更多
关键词 Randomized Linear Model.Outliers Likelihood Ratio Test UNIFORMLY
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Analysis of Genetic Diversity of Four Subpopulations of Chimonobambusa rivularis Yi in Sichuan 被引量:1
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作者 C. Y. Yang S. P. Gao +3 位作者 B. Wang Q. B. Chen L. J. Yang W. D. Liu 《Journal of Agricultural Science and Technology(B)》 2011年第1期95-100,共6页
A study of the genetic diversity within four subpopulations of Chimonobambusa rivularis Yi and adaptations to altitude, habitat and related factors in Qionglai City of Sichuan province in China, analyzed by random amp... A study of the genetic diversity within four subpopulations of Chimonobambusa rivularis Yi and adaptations to altitude, habitat and related factors in Qionglai City of Sichuan province in China, analyzed by random amplified polymorphic DNA technique. 22 random primers were selected in the amplification and 375 repetitive loci with 350 polymorphic loci were produced. The total average percentage of amplification loci was 93.3%. The genetic diversity of every subpopulation was medium on (the percentage of amplification loci was 49.33%-66.67%). The genetic diversity of high altitude samples of Zhengtiantai was lower than that of low altitude Wutonggang's. There was no obvious differentiation between two subpopulations of Zhengtiantais. The correlation is very low between altitude and the amplification loci and the genetic distance, Pearson correlation coefficient was 0.431 and 0.488 (P 〈 0.01). Through investigation, the primary cause of heredity multiplicity drops was that the habitat had been destroyed by tourism development and other human disturbance. 展开更多
关键词 Chimonobambusa rivularis Yi DNA-RAPD SUBPOPULATION genetic diversity altitude.
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