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气垫带式输送机图解选型法
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作者 周全申 朱同顺 +1 位作者 刘存中 李广玉 《粮食与饲料工业》 CAS 北大核心 2014年第2期8-12,共5页
基于气垫带式输送机设计理论,提出"当量功率"、"当量风压"、"当量风量"、"空车功率"、"空车风量"、"空车风压"等概念,得到了一种气垫带式输送机图解选型方法,利用该方法... 基于气垫带式输送机设计理论,提出"当量功率"、"当量风压"、"当量风量"、"空车功率"、"空车风量"、"空车风压"等概念,得到了一种气垫带式输送机图解选型方法,利用该方法可以直观、快捷地选择满足工程要求的气垫带式输送机型号、驱动功率、风量及风压等相关参数。 展开更多
关键词 气垫带式输送机 “当量功率” “当量风量” “当量风压” “空车功率” “空车风量” “空车风压” 图解选型法
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直接空冷机组电动给水泵选型建议 被引量:2
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作者 徐传海 《电力勘测设计》 2006年第3期42-45,共4页
针对大容量直接空冷机组按照规定选用电动给水泵所伴生的问题,提出了按TRL工况选用电动给水泵的方法。此法节电效果巨大,就3台300MW直接空冷机组的电厂而言年节电约107kW h。
关键词 直接空冷机组 电动给水泵 节电选型法.
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600MW直接空冷机组电动调速给水泵选型建议
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作者 徐传海 《热机技术》 2006年第2期49-52,共4页
针对600MW直接空冷机组按规定所选的电动调速给水泵存在的液力耦合器功耗大、电动机容量大等问题,提出以TRL工况汽轮机进汽量为基数确定给水泵设计参数的选型法。600MW直接空冷机组运行一年至少节电346×10^4kWh。
关键词 直接空冷机组 电动调速给水泵 TRL工况选型法
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基于MATLAB GUI对燃气调压阀数值计算方法
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作者 袁庆洪 刘可 张燕 《机械工程师》 2020年第11期44-46,共3页
调压阀的选型通常有流量表选型法和数值计算法。流量表选型法只针对具体规格和型号的调压阀。为解决不同压力和任意流量的调压阀选型,通过MATLAB GUI编制程序的方法对调压阀的类型和大小进行初选,可以快速选择不同种类和结构的调压阀,... 调压阀的选型通常有流量表选型法和数值计算法。流量表选型法只针对具体规格和型号的调压阀。为解决不同压力和任意流量的调压阀选型,通过MATLAB GUI编制程序的方法对调压阀的类型和大小进行初选,可以快速选择不同种类和结构的调压阀,并明确阀门开度和可调比,为最终选择合适的调压阀提供数值依据。通过数值计算法和流量表选型法的数据对比,可以进一步验证数值计算法的合理性。 展开更多
关键词 调压阀 数值计算 流量表选型法 MATLAB GUI
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立式钻床立柱结构动静态分析与结构改进 被引量:4
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作者 仇君 朱晓慧 +1 位作者 黄伟 李小周 《机床与液压》 北大核心 2012年第7期152-155,共4页
以有限元理论为基础,建立立式钻床立柱结构的参数化模型,进行静态有限元分析,分析立柱结构承载及变形特点。在此基础上,采用选型法对立柱进行结构改进,并对改进后的模型做动态性能分析。结果表明:优化后,立柱静态性能提高,质量减少12.8%... 以有限元理论为基础,建立立式钻床立柱结构的参数化模型,进行静态有限元分析,分析立柱结构承载及变形特点。在此基础上,采用选型法对立柱进行结构改进,并对改进后的模型做动态性能分析。结果表明:优化后,立柱静态性能提高,质量减少12.8%;立柱固有频率值与原固有频率值相近,满足结构动态性能的要求。 展开更多
关键词 立柱 动静态有限元分析 选型法 结构改进
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Method and standard for selecting elite nut trees of Korean pine 被引量:8
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作者 杨凯 谷会岩 +2 位作者 扬凯 李春英 杨逢建 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第2期84-88,146,共5页
The fruit-bearing quantities of nut Korean pines (Pinus Koraiensis) of natural stands in Changbai Mountain, Xiaoxing'an Mountain, and Wanda Mountain and of artificial forest in Hegang area of Heilongjiang Province... The fruit-bearing quantities of nut Korean pines (Pinus Koraiensis) of natural stands in Changbai Mountain, Xiaoxing'an Mountain, and Wanda Mountain and of artificial forest in Hegang area of Heilongjiang Province were investigated and measured by seed collection of singletree during 1988–1998. In order to evaluate the elite nut tree of fructification, the characteristics of fructification of Korena pine, including, the fruit-bearing quantity, output of seed, quantity of cone, cone size, seed size, the ratio of null seed by solid seed, seed percentage of cone, rate of the cones infested with pest, and fruit-bearing index, etc., were analyzed with the variance analysis, multiple comparison and stepwise regression to obtain the contribution ratio of each fruit-bearing factor to fruit-bearing quantity. The multiple correlation factors and the partial correlation factors for fruit-bearing quantities of Korean pine were determined for different geographical areas, and the cone length, thousand-grain-weight, and the seed percentage of cone were considered as important indices for selection of elite trees. The method of modified weighted coefficients was adopted to select the elite nut trees of Korean pine. Standards for selecting elite nut trees from the natural stands and artificial forest of Korean pine were established. This study could provde selection method and standard of elite nut trees for setting up seed orchard of Korean Pine. 展开更多
关键词 Korean pine Elite nut tree Selection method
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Gaussian mixture model clustering with completed likelihood minimum message length criterion 被引量:1
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作者 曾洪 卢伟 宋爱国 《Journal of Southeast University(English Edition)》 EI CAS 2013年第1期43-47,共5页
An improved Gaussian mixture model (GMM)- based clustering method is proposed for the difficult case where the true distribution of data is against the assumed GMM. First, an improved model selection criterion, the ... An improved Gaussian mixture model (GMM)- based clustering method is proposed for the difficult case where the true distribution of data is against the assumed GMM. First, an improved model selection criterion, the completed likelihood minimum message length criterion, is derived. It can measure both the goodness-of-fit of the candidate GMM to the data and the goodness-of-partition of the data. Secondly, by utilizing the proposed criterion as the clustering objective function, an improved expectation- maximization (EM) algorithm is developed, which can avoid poor local optimal solutions compared to the standard EM algorithm for estimating the model parameters. The experimental results demonstrate that the proposed method can rectify the over-fitting tendency of representative GMM-based clustering approaches and can robustly provide more accurate clustering results. 展开更多
关键词 Gaussian mixture model non-Gaussian distribution model selection expectation-maximization algorithm completed likelihood minimum message length criterion
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Digital Rights Management:Model,Technology and Application 被引量:7
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作者 Zhaofeng Ma 《China Communications》 SCIE CSCD 2017年第6期156-167,共12页
with rapid achievement of current information technology and computing ability and applications,much more digital content such as films,cartoons,design drawings,office documents and software source codes are produced ... with rapid achievement of current information technology and computing ability and applications,much more digital content such as films,cartoons,design drawings,office documents and software source codes are produced in daily work,however to protect the content being copying,shared or deliberately stolen by inside or outside,digital rights management(DRM) became more and more important for digital content protection.In this paper,we studied various DRM model,technology and application,and first proposed DRM Security Infrastructure(DSI),in which we defined encryption,hash,signature algorithm,watermarking algorithms,authentication,usage control,trusted counter,conditional trace,secure payment,and based on the DSI we then proposed a whole classification approach and architecture of all kinds of DRMs,in which we proposed 6 typical classes of copyrights and content protection DRMs architecture:(1) Software-oriented DRM,(2) e Book-oriented DRM,(3) Video-oriented DRM,(4) Image-Oriented DRM(5) Unstructured data oriented DRM,(6) Text-oriented DRM.Based on the above DSI,we then proposed a dynamic DRM model selection method for various DRM application,which can be adapted dynamically for different technology of different applications,which can provide awhole solution for variant DRM development in a rapid and customized mode.The proposed DRM method,technology and application in this paper provided a common,flexible and extendable solution for variant DRM scenes,and can support rapid and customized development.Moreover,we proposed an opinion that the future life will enter into a new era that the content usage and consumption will not again adopt DRM technology rather than with law,liberty and morality. 展开更多
关键词 digital rights management drm security infrastructure ENCRYPTION WATERMARK usage control drm-free
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The Research on Social Networks Public Opinion Propagation Influence Models and Its Controllability 被引量:9
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作者 Lejun Zhang Tong Wang +3 位作者 Zilong Jin Nan Su Chunhui Zhao Yongjun He 《China Communications》 SCIE CSCD 2018年第7期98-110,共13页
Public opinion propagation control is one of the hot topics in contemporary social network research. With the rapid dissemination of information over the Internet, the traditional isolation and vaccination strategies ... Public opinion propagation control is one of the hot topics in contemporary social network research. With the rapid dissemination of information over the Internet, the traditional isolation and vaccination strategies can no longer achieve satisfactory results. A positive guidance technology for public opinion diffusion is urgently needed. First, based on the analysis of influence network controllability and public opinion diffusion, a positive guidance technology is proposed and a new model that supports external control is established. Second, in combination with the influence network, a public opinion propagation influence network model is designed and a public opinion control point selection algorithm(POCDNSA) is proposed. Finally, An experiment verified that this algorithm can lead to users receiving the correct guidance quickly and accurately, reducing the impact of false public opinion information; the effect of CELF is no better than that of the POCDNSA algorithm. The main reason is that the former is completely based on the diffusion cascade information contained in the training data, but does not consider the specific situation of the network structure and the diffusion of public opinion information in the closed set. thus, the effectiveness and feasibility of the algorithm is proven. The findings of this article therefore provide useful insights for the implementation of public opinion control. 展开更多
关键词 social network public opinion propagation control influence network
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A new improved Alopex-based evolutionary algorithm and its application to parameter estimation 被引量:1
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作者 桑志祥 李绍军 董跃华 《Journal of Central South University》 SCIE EI CAS 2013年第1期123-133,共11页
In this work, focusing on the demerit of AEA (Alopex-based evolutionary algorithm) algorithm, an improved AEA algorithm (AEA-C) which was fused AEA with clonal selection algorithm was proposed. Considering the irratio... In this work, focusing on the demerit of AEA (Alopex-based evolutionary algorithm) algorithm, an improved AEA algorithm (AEA-C) which was fused AEA with clonal selection algorithm was proposed. Considering the irrationality of the method that generated candidate solutions at each iteration of AEA, clonal selection algorithm could be applied to improve the method. The performance of the proposed new algorithm was studied by using 22 benchmark functions and was compared with original AEA given the same conditions. The experimental results show that the AEA-C clearly outperforms the original AEA for almost all the 22 benchmark functions with 10, 30, 50 dimensions in success rates, solution quality and stability. Furthermore, AEA-C was applied to estimate 6 kinetics parameters of the fermentation dynamics models. The standard deviation of the objective function calculated by the AEA-C is 41.46 and is far less than that of other literatures' results, and the fitting curves obtained by AEA-C are more in line with the actual fermentation process curves. 展开更多
关键词 ALOPEX evolutionary algorithm Alopex-based evolutionary algorithm clone selection parameter estimation
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Type Selection of Burning Equipment for Slagging-Coal Boilers
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作者 Li Weidong Zhou Hongguang +1 位作者 Zhang Jingwu Xu Chuankai 《Electricity》 2012年第1期32-35,共4页
The type selection of burning equipment for boilers is affected significantly by the slagging characteristics of coal. Based on the engineering statistics method, the designed furnace parameters are obtained from the ... The type selection of burning equipment for boilers is affected significantly by the slagging characteristics of coal. Based on the engineering statistics method, the designed furnace parameters are obtained from the 600-MW and 1 000-MW boilers with tangential firing and wall firing. The power and arrangement of the burners are analyzed. Their impacts on slagging on heating surfaces and the carbon contents in the ash and cinders are also discussed. Thermal parameters of furnace are recommended for boilers of 600 MW and 1 000 MW firing slagging coal in the design. The static or rotary classifier should be the first choice for the pulverizing system. 展开更多
关键词 burning equipment slagging coal type selection
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Smartphone Malware Detection Model Based on Artificial Immune System 被引量:1
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作者 WU Bin LU Tianliang +2 位作者 ZHENG Kangfeng ZHANG Dongmei LIN Xing 《China Communications》 SCIE CSCD 2014年第A01期86-92,共7页
In order to solve the problem that me traditional signature-based detection technology cannot effectively detect unknown malware, we propose in this study a smartphone malware detection model (SP-MDM) based on artif... In order to solve the problem that me traditional signature-based detection technology cannot effectively detect unknown malware, we propose in this study a smartphone malware detection model (SP-MDM) based on artificial immune system, in which static malware analysis and dynamic malware analysis techniques are combined, and antigens are generated by encoding the characteristics extracted from the malware. Based on negative selection algorithm, the mature detectors are generated. By introducing clonal selection algorithm, the detectors with higher affinity are selected to undergo a proliferation and somatic hyper-mutation process, so that more excellent detector offspring can be generated. Experimental result shows that the detection model has a higher detection rate for unknown smartphone malware, and better detection performance can be achieved by increasing the clone generation. 展开更多
关键词 artificial immune system smartphonemalware DETECTION negative selection clonalselection
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Statistical and Geometrical Way of Model Selection for a Family of Subdivision Schemes 被引量:1
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作者 Ghulam MUSTAFA 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2017年第5期1077-1092,共16页
The objective of this article is to introduce a generalized algorithm to produce the m-point n-ary approximating subdivision schemes(for any integer m, n ≥ 2). The proposed algorithm has been derived from uniform B-s... The objective of this article is to introduce a generalized algorithm to produce the m-point n-ary approximating subdivision schemes(for any integer m, n ≥ 2). The proposed algorithm has been derived from uniform B-spline blending functions. In particular, we study statistical and geometrical/traditional methods for the model selection and assessment for selecting a subdivision curve from the proposed family of schemes to model noisy and noisy free data. Moreover, we also discuss the deviation of subdivision curves generated by proposed family of schemes from convex polygonal curve. Furthermore, visual performances of the schemes have been presented to compare numerically the Gibbs oscillations with the existing family of schemes. 展开更多
关键词 Approximating subdivision schemes B-spline blending function Convex polygon Statistical and geometrical methods Model selection andassessment
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Adaptive quantile regression with precise risk bounds 被引量:1
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作者 TIAN MaoZai CHAN Ngai Hang 《Science China Mathematics》 SCIE CSCD 2017年第5期875-896,共22页
An adaptive local smoothing method for nonpaxametric conditional quantile regression models is considered in this paper. Theoretical properties of the procedure are examined. The proposed method is fully adaptive in t... An adaptive local smoothing method for nonpaxametric conditional quantile regression models is considered in this paper. Theoretical properties of the procedure are examined. The proposed method is fully adaptive in the sense that no prior information about the structure of the model is assumed. The fully adaptive feature not only allows varying bandwidths to accommodate jumps or instantaneous slope changes, but also al- lows the algorithm to be spatially adaptive. Under general conditions, precise risk bounds for homogeneous and heterogeneous cases of the underlying conditional quantile curves are established. An automatic selection algo- rithm for locally adaptive bandwidths is also given, which is applicable to higher dimensional cases. Simulation studies and data analysis confirm that the proposed methodology works well. 展开更多
关键词 adaptive smoothing automatic bandwidths conditional quantile risk bounds ROBUSTNESS
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Acquisition of English Reflexive Verb Constructions:Roles of Syntactical Indeterminacy and Token Frequency 被引量:1
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作者 Xu Chengping 《Chinese Journal of Applied Linguistics》 2016年第3期251-268,374,共19页
This study draws on usage-based approach to language learning and investigates the role of syntactical indeterminacy and token frequency in constructional acquisition, for which reflexive verb constructions were selec... This study draws on usage-based approach to language learning and investigates the role of syntactical indeterminacy and token frequency in constructional acquisition, for which reflexive verb constructions were selected as the testing field. Syntactic structures of reflexive verbs are either by reflexive constructions or adjectival passive, which have a polysemous interrelationship within the verb. To examine whether syntactic indeterminacy and token frequency play a role in the acquisition of reflexive verb constructions, a test of reflexive verb constructions and a baseline test formed with transitive verbs were developed and administered to L2 learners of an intermediate proficiency level. The findings show: (1) L2 reflexive verb constructions were less acquired than transitive constructions, suggesting that syntactic indeterminacy had an impact upon sentence production; (2) no significant difference was found between the productions of reflexive constructions and adjectival passives, but descriptive statistics showed that learners were attracted to the adjectival passive for production; (3) production of both syntactic structures reflected token frequency trend from COCA, indicating the important role of frequency in complex constructional acquisition. 展开更多
关键词 syntactical indeterminacy token frequency reflexive verb
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A SELF-SIMILAR LOCAL NEURO-FUZZY MODEL FOR SHORT-TERM DEMAND FORECASTING 被引量:2
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作者 HASSANI Hossein ABDOLLAHZADEH Majid +1 位作者 IRANMANESH Hossein MIRANIAN Arash 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2014年第1期3-20,共18页
This paper proposes a selfsimilar local neurofuzzy (SSLNF) model with mutual informati onbased input selection algorithm for the shortterm electricity demand forecasting. The proposed self similar model is composed ... This paper proposes a selfsimilar local neurofuzzy (SSLNF) model with mutual informati onbased input selection algorithm for the shortterm electricity demand forecasting. The proposed self similar model is composed of a number of local models, each being a local linear neurofuzzy (LLNF) model, and their associated validity functions and can be interpreted itself as an LLNF model. The proposed model is trained by a nested local liner model tree (NLOLIMOT) learning algorithm which partitions the input space into axisorthogonal subdomains and then fits an LLNF model and its associated validity function on each subdomain. Furthermore, the proposed approach allows different input spaces for rule premises (validity functions) and consequents (local models). This appealing property is employed to assign the candidate input variables (i.e., previous load and temperature) which influence shortterm electricity demand in linear and nonlinear ways to local models and validity functions, respectively. Numerical results from shortterm load forecasting in the New England in 2002 demonstrated the accuracy of the SSLNF model for the STLF applications. 展开更多
关键词 Mutual information self-similar local neuro-fuzzy model short-term load forecasting.
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机房电力有源滤波器和静止无功补偿器应用实用技术(二)
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作者 吕纯强 《机房技术与管理》 2016年第5期6-11,共6页
本文介绍了数据中心机房供配电系统电力无功补偿和谐波治理方面节能降耗并提高其系统安全可靠性的先进的补偿技术和应用方面的实用技术,包括静止无功补偿器SVG和电力有源滤波器APF工作原理、计算选型要点和方法、机房供配电系统电力补... 本文介绍了数据中心机房供配电系统电力无功补偿和谐波治理方面节能降耗并提高其系统安全可靠性的先进的补偿技术和应用方面的实用技术,包括静止无功补偿器SVG和电力有源滤波器APF工作原理、计算选型要点和方法、机房供配电系统电力补偿方案和SVG、APF应用注意事项,通俗易懂、实用性强。 展开更多
关键词 无功补偿 谐波治理 静止无功补偿器SVG 电力有源滤波器APF 选型 查表计算 容量计算 现场测试确定容量 集中补偿 部分补偿 就地补偿.
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机房电力有源滤波器和静止无功补偿器应用实用技术(一)
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作者 吕纯强 《机房技术与管理》 2016年第4期18-23,共6页
本文介绍了数据中心机房供配电系统电力无功补偿和谐波治理方面节能降耗并提高其系统安全可靠性的先进的补偿技术和应用方面的实用技术,包括静止无功补偿器SVG和电力有源滤波器APF工作原理、计算选型要点和方法、机房供配电系统电力补... 本文介绍了数据中心机房供配电系统电力无功补偿和谐波治理方面节能降耗并提高其系统安全可靠性的先进的补偿技术和应用方面的实用技术,包括静止无功补偿器SVG和电力有源滤波器APF工作原理、计算选型要点和方法、机房供配电系统电力补偿方案和SVG、APF应用注意事项,通俗易懂、实用性强。 展开更多
关键词 无功补偿 谐波治理 静止无功补偿器SVG 电力有源滤波器APF 选型 查表计算 容量计算 现场测试确定容量 集中补偿 部分补偿 就地补偿
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Variable Selection of Varying Dispersion Student-t Regression Models 被引量:1
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作者 ZHAO Weihua ZHANG Riquan 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2015年第4期961-977,共17页
The Student-t regression model is a useful extension of the normal model,which can be used for statistical modeling of data sets involving errors with heavy tails and/or outliers and provides robust estimation of mean... The Student-t regression model is a useful extension of the normal model,which can be used for statistical modeling of data sets involving errors with heavy tails and/or outliers and provides robust estimation of means and regression coefficients.In this paper,the varying dispersion Student-t regression model is discussed,in which both the mean and the dispersion depend upon explanatory variables.The problem of interest is simultaneously select significant variables both in mean and dispersion model.A unified procedure which can simultaneously select significant variable is given.With appropriate selection of the tuning parameters,the consistency and the oracle property of the regularized estimators are established.Both the simulation study and two real data examples are used to illustrate the proposed methodologies. 展开更多
关键词 LASSO SCAD Student-t distribution variable selection varying dispersion.
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