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Research Progress on Functional Components and Pharmacological Effects of Red Jujube ( Ziziphus jujuba Mill.)
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作者 Qian SHI 《Agricultural Biotechnology》 CAS 2023年第4期71-74,87,共5页
Red jujube(Ziziphus jujuba Mill.),as a traditional Chinese medicine and edible plant,has a long history and extensive uses.Red jujubes are not only widely used in the food industry and traditional Chinese medicine pre... Red jujube(Ziziphus jujuba Mill.),as a traditional Chinese medicine and edible plant,has a long history and extensive uses.Red jujubes are not only widely used in the food industry and traditional Chinese medicine preparations,but also have attracted widespread research interest due to their rich functional components and various pharmacological effects.This paper reviewed the main functional components of jujubes,including polysaccharides,triterpenoid saponins,organic acids and alkaloids,and discussed in detail the pharmacological effects of these components such as blood sugar-regulating,antioxidant,anti-inflammatory and anti-tumor effects.Furthermore,the paper also summarized the safety issues such as drug interactions and toxic side effects of jujubes,and prospected the future development direction of jujube research. 展开更多
关键词 JUJUBE functional components Pharmacological effects
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Research Progress of Tea Functional Components in the Prevention and Treatment of Lung Cancer
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作者 Hao Wu Qin-You Ren +7 位作者 Xing Tang Hui Zhang Can-Jun Zhao Jian-Gang Yang Lan-Hui Zhang Ao-Yu Shi Bi-Zhu Geng Jin Zheng 《Food Therapy and Health Care》 2020年第1期12-23,共12页
The incidence and mortality of lung cancer rank first among all malignant tumors,so the prevention and treatment of lung cancer has become a worldwide concern.Tea is one of the most popular healthy drinks in the world... The incidence and mortality of lung cancer rank first among all malignant tumors,so the prevention and treatment of lung cancer has become a worldwide concern.Tea is one of the most popular healthy drinks in the world.A large number of studies have shown that tea polyphenols,theophylline,tea pigments,theanine,tea polysaccharides and other functional components in tea can promote apoptosis of cancer cells,inhibit proliferation and division of cancer cells,and regulate the expression of tumor-related gene protein through strong antioxidant activity,inhibiting the activity of key enzymes and blocking signal transduction to prevent and treat the occurrence,development and metastasis of lung cancer.In this study,the application of tea in the prevention and treatment of lung cancer was elaborated through the traceability,basic components,basic theory of traditional Chinese medicine,anti-lung cancer mechanism,expert opinions and so on,in order to provide direction for the prevention and treatment of tea and lung cancer. 展开更多
关键词 TEA Lung cancer functional components Traditional Chinese medicine Research progress
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DIRECT AND ADAPTIVE SLICING ON CAD MODEL OF IDEAL FUNCTIONAL MATERIAL COMPONENTS (IFMC) 被引量:3
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作者 XuDaoming JiaZhenyuan GuoDongming 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第1期139-144,共6页
A brand new direct and adaptive slicing approach is proposed, which canapparently improve the part accuracy and reduce the building time. At least two stages are includedin this operation: getting the crossing contour... A brand new direct and adaptive slicing approach is proposed, which canapparently improve the part accuracy and reduce the building time. At least two stages are includedin this operation: getting the crossing contour of the cutting plane with the solid part anddetermining the layer thickness. Apart from usual SPI algorithm, slicing of the solid model has itsspecial requirements. Enabling the contour line segments of the cross-section as long as possible isone of them, which is for improving manufacturing efficiency and is reached by adaptively adjustingthe step direction and the step size at every crossing point to obtain optimized secant height. Thelayer thickness determination can be divided into two phases: the geometry-based thicknessestimation and the material-based thickness verifying. During the former phase, the geometrytolerance is divided into two parts: a variety of curves are approximated by a circular arc, whichintroduces the first part, and the deviation error between the contour line in LM process and thecircular arc generates the second part. The latter phase is mainly verifying the layer thicknessestimated in the former stage and determining a new one if necessary. In addition, an example usingthis slicing algorithm is also illustrated. 展开更多
关键词 Rapid prototyping Ideal functional material components Direct and adaptiveslicing Surface/plane intersection MARCHING
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CAE-integrated Fabrication of Functionally Graded Components
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作者 Y C Yeung K M Yu 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期214-215,共2页
A typical contemporary computerized product develop me nt workflow is outlined in Fig.1. Product geometry information is first prep ared with computer-aided design (CAD) software. The CAD format can then be com munica... A typical contemporary computerized product develop me nt workflow is outlined in Fig.1. Product geometry information is first prep ared with computer-aided design (CAD) software. The CAD format can then be com municated to other downstream-computerized applications like, computer-aided e ngineering analysis (CAE), computer-aided manufacturing (CAM) and/or rapid prot otyping. Since design may need to be modified to incorporate new requirements, a loop back path is also depicted in Fig.1. The design engineers will check ac cording to their experience, result of physical test and CAE simulation to decid e whether redesign is needed or not. If the design passes all tests, its pr ototype or product can be produced. Otherwise, the current practice is to chang e its geometry and/or select a more appropriate material. The iteration repeat s until the latest version satisfies the engineering specification and customer requirements. Note that the material is homogeneous in the part to be designed. With the advent of functionally graded material (FGM) research, a new workflow will become possible. Components incorporating FGM’s can be designed to achieve levels of performance superior to that of homogeneous materials by combining the desirable properties of each constituent phase. Theoretically, the material composition can be tailo red within a component to achieve local control of properties; for example, form ability, corrosion resistance, hardness, toughness, and so on. By such local co ntrol, monolithic components can be created that integrate the function of multi ple discrete components, saving part count, space, weight, and enabling concepts that would otherwise be impractical. Controlling the spatial distribution of p roperties via composition will allow for control of the state of the entire comp onent (the state of residual stress in a component). There are various methods p roposed to produce FGM components. In particular, solid freeform fabrication ( SFF) methods are commonly used to directly fabricate an FGM part in an additive fashion directly from a computer controlled, layer-by-layer, additive process in which a standard CAD is sliced into a series of horizontal planes. Common SF F techniques being investigated include three-dimensional printing (3DP), Lamin ate Object Manufacturing (LOM), Extrusion Freeform Fabrication (EFF), Selective Laser Sintering (SLS) and even Stereolithography (SL). Fig.1 Current CAE design workflow Fig.2 Proposed CAE design workflow for FGM Albeit the feasibility to fabricate FGM components, one gap still needs to be fi lled for real life FGM product design; namely, where and how to grade the compon ent. This paper will, thus, address issues on incorporating FGM for design impr ovement. Rather than changing the geometry or reselecting a new material, a FGM approach can be employed in design enhancement as shown in Fig.2. The same geo metry and material is retained except that functional property in needed regions is selectively reinforced. As in conventional workflow, CAE simulation is perf ormed after CAD modelling. CAE simulation is preferred since physical test is v ery expensive and most of them are destructive. Moreover, the experience of the engineers may not be accurate. More importantly, the result of CAE simulation is used in this research to produce a stress intensity map for selective reinfor cement. The map will be converted to tool path control signals for generating FG component via SFF machine. On the implementation side, SolidWorks is used fo r CAD modeling, COSMOS/Works is used for CAE simulation. The model is then selec tively reinforced according to the simulation result to produce a FGM enriched p ath plan to drive the Z-corp machine. Case studies are performed to verify the approach. The preliminary result is positive. Future extension to material oth er than starch and plaster powders and enhancement other than stress distributio n may be explored. In conclusion, a CAE-based methodology for FGM product des ign 展开更多
关键词 CAE-integrated Fabrication of functionally Graded components FGM
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Unsupervised Functional Data Clustering Based on Adaptive Weights
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作者 Yutong Gao Shuang Chen 《Open Journal of Statistics》 2023年第2期212-221,共10页
In recent years, functional data has been widely used in finance, medicine, biology and other fields. The current clustering analysis can solve the problems in finite-dimensional space, but it is difficult to be direc... In recent years, functional data has been widely used in finance, medicine, biology and other fields. The current clustering analysis can solve the problems in finite-dimensional space, but it is difficult to be directly used for the clustering of functional data. In this paper, we propose a new unsupervised clustering algorithm based on adaptive weights. In the absence of initialization parameter, we use entropy-type penalty terms and fuzzy partition matrix to find the optimal number of clusters. At the same time, we introduce a measure based on adaptive weights to reflect the difference in information content between different clustering metrics. Simulation experiments show that the proposed algorithm has higher purity than some algorithms. 展开更多
关键词 functional Data Unsupervised Learning Clustering functional Principal Component Analysis Adaptive Weight
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Biomass Allocation Patterns of Alpine Grassland Species and Functional Groups along a Precipitation Gradient on the Northern Tibetan Plateau 被引量:7
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作者 WU Jian-shuang SHEN Zhen-xi +1 位作者 ZHANG Xian-zhou SHI Pei-li 《Journal of Mountain Science》 SCIE CSCD 2013年第6期1097-1108,共12页
Variations in the fractions of biomass allocated to functional components are widely considered as plant responses to resource availability for grassland plants. Observations indicated shoots isometrically relates to ... Variations in the fractions of biomass allocated to functional components are widely considered as plant responses to resource availability for grassland plants. Observations indicated shoots isometrically relates to roots at the community level but allometrically at the species level in Tibetan alpine grasslands. These differences may result from the specific complementarity of functional groups between functional components, such as leaf, root, stem and reproductive organ. To test the component complementary responses to regional moisture variation, we conducted a multi-site transect survey to measure plant individual size and component biomass fractions of common species belonging to the functional groups: forbs, grasses, legumes and sedges on the Northern Tibetan Plateau in peak growing season in 2010. Along the mean annual precipitation (MAP) gradient, we sampled 7o species, in which 2o are in alpine meadows, 20 in alpine steppes, 15 in alpine desert-steppes and 15 in alpine deserts, respectively. Our results showed that the size of alpine plants is small with individual biomass mostly lower than 1.0 g. Plants keep relative conservative component individual responses moisture functional fractions across alpine grasslands at the level. However, the complementary between functional components to variations specifically differ among groups. These results indicate that functional group diversity may be an effective tool for scaling biomass allocation patterns from individual up to community level. Therefore, it is necessary andvaluable to perform intensive and systematic studies on identification and differentiation the influences of compositional changes in functional groups on ecosystem primary services and processes. 展开更多
关键词 Biomass fractions Complementaryresponse functional components functional groups Changtang Plateau
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Concept and Research Progress of Functional Feed 被引量:2
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作者 明炜 丁磊磊 《Agricultural Science & Technology》 CAS 2017年第7期1322-1324,1331,共4页
The concept and research progress of functional feed were summarized. Compared with the basic nutrition, functional feed is a kind of new health care feed which contains functional ingredients, and can promote the gro... The concept and research progress of functional feed were summarized. Compared with the basic nutrition, functional feed is a kind of new health care feed which contains functional ingredients, and can promote the growth of animal health, enhance immunity, improve the quality of animal products, improve the level of ani- mal welfare, reduce environmental pollution, improve the ecological environment, as well as increase the economic benefits. Studies on the functional feed are mainly concentrated in the development of functional feed products, and but few to under- stand the compositions and compatibility mechanism of the functional components that have the function effects. Moreover, these functional components are low in plants, so the wide application in feed industry requires research on biological engi- neering and chemical synthesis, which will become the trend of future research. 展开更多
关键词 functional feed functional components CONCEPT Research progress
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Comparative Study on Functional Properties of Mulberry Black Tea Fermented by Phellinus igniarius and Eurotium cristatum 被引量:2
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作者 Yanrui MA Xuezhen LI +4 位作者 Xuemei YANG Guangpeng LIU Le CHU Yan ZHAO Fatao HE 《Medicinal Plant》 CAS 2022年第3期14-17,共4页
[Objectives]To compare functional properties of mulberry black tea fermented by Phellinus igniarius and Eurotium cristatum.[Methods]The functional components of mulberry black tea fermented by P.igniarius and E.crista... [Objectives]To compare functional properties of mulberry black tea fermented by Phellinus igniarius and Eurotium cristatum.[Methods]The functional components of mulberry black tea fermented by P.igniarius and E.cristatum,the deep processing and health care effects of two probiotic fungi were explored.[Results]The polysaccharide content in the tea fermented by P.igniarius was the highest at 0.410 mg/mL,and the hydroxyl radical scavenging rate was the strongest,reaching 60.31%;the content of flavonoids in the tea fermented by E.cristatum was the highest,reaching 60.65μg/mL,and the content of polysaccharides was 83.17%higher than that of mulberry black tea,reaching 0.279 mg/mL.[Conclusions]The mulberry black tea fermented by P.igniarius and E.cristatum has improved in different functional components,and has its own advantages in aroma and mouthfeel,so it has certain research value and market prospect. 展开更多
关键词 Phellinus igniarius Eurotium cristatum Mulberry black tea functional components
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Study on Influence of Functional Composition Distribution on Combustion Performance of a Modified Single Base Propellant
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作者 刘波 王琼林 +5 位作者 刘少武 于慧芳 李达 姚月娟 潘清 魏伦 《Defence Technology(防务技术)》 CAS 2012年第2期114-118,共5页
The modified single base propellant samples were prepared by impregnating blasting oil into single base grains and deactivating deterrent in water medium. The concentration distribution of functional compositions in t... The modified single base propellant samples were prepared by impregnating blasting oil into single base grains and deactivating deterrent in water medium. The concentration distribution of functional compositions in this propellant was determined by using FTIR micro-spectroscopy. Its combustion performance was investigated by means of closed-bomb and interior ballistic tests. The results show that the concentration of NG distributes parabolically along the radius and the concentration of NA decreases from the surface to the centre exponentially. The deeper the NG impregnates, the slower the NA concentration decreases, the stronger the progressive combustion is and the better the interior ballistic performance is. When the depth corresponding to maximum NG concentration is about 1/2 of the web and the NA decreases slowly, the progressive combustion is the strongest and the interior ballistic performance is the best. 展开更多
关键词 physical chemistry modified single base propellant functional component CONCENTRATION combustion performance
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Functional Fibers and Functional Fiber‑Based Components for High‑Power Lasers 被引量:8
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作者 Xiao Chen Tianfu Yao +4 位作者 Liangjin Huang Yi An Hanshuo Wu Zhiyong Pan Pu Zhou 《Advanced Fiber Materials》 SCIE EI 2023年第1期59-106,共48页
The success of high-power fiber lasers is fueled by maturation of active and passive fibers,combined with the availability of high-power fiber-based components.In this contribution,we first overview the enormous poten... The success of high-power fiber lasers is fueled by maturation of active and passive fibers,combined with the availability of high-power fiber-based components.In this contribution,we first overview the enormous potential of rare-earth doped fibers in spectral coverage and recent developments of key fiber-based components employed in high-power laser systems.Subsequently,the emerging functional active and passive fibers in recent years,which exhibit tremendous advantages in balancing or mitigating parasitic nonlinearities hindering high-power transmission,are outlined from the perspectives of geo-metric and material engineering.Finally,novel functional applications of conventional fiber-based components for nonlinear suppression or spatial mode selection,and correspondingly,the high-power progress of function fiber-based components in power handling are introduced,which suggest more flexible controllability on high-power laser operations. 展开更多
关键词 High-power laser Laser fiber Passive fiber-based component functional fiber functional fiber-based component
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Clustering for Bivariate Functional Data
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作者 Shi-yun CAO Yan-qiu ZHOU +1 位作者 Yan-ling WAN Tao ZHANG 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2024年第3期613-629,共17页
In this paper,we consider the clustering of bivariate functional data where each random surface consists of a set of curves recorded repeatedly for each subject.The k-centres surface clustering method based on margina... In this paper,we consider the clustering of bivariate functional data where each random surface consists of a set of curves recorded repeatedly for each subject.The k-centres surface clustering method based on marginal functional principal component analysis is proposed for the bivariate functional data,and a novel clustering criterion is presented where both the random surface and its partial derivative function in two directions are considered.In addition,we also consider two other clustering methods,k-centres surface clustering methods based on product functional principal component analysis or double functional principal component analysis.Simulation results indicate that the proposed methods have a nice performance in terms of both the correct classification rate and the adjusted rand index.The approaches are further illustrated through empirical analysis of human mortality data. 展开更多
关键词 bivariate functional data -centres surface clustering functional principal component analysis partial derivative function
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Healthy function and high valued utilization of edible fungi 被引量:27
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作者 Yanrong Zhang Dawei Wang +5 位作者 Yuetong Chen Tingting Liu Shanshan Zhang Hongxiu Fan Hongcheng Liu Yu Li 《Food Science and Human Wellness》 SCIE 2021年第4期408-420,共13页
Edible fungi are large fungi with high added value that can be utilized as resources.They are rich in high-quality protein,carbohydrate,various vitamins,mineral elements and other nutrients,and are characterized by hi... Edible fungi are large fungi with high added value that can be utilized as resources.They are rich in high-quality protein,carbohydrate,various vitamins,mineral elements and other nutrients,and are characterized by high protein,low sugar,low fat and low cholesterol.In addition,edible fungi contain a variety of bioactive substances,such as polysaccharides,dietary fiber,steroids,polyphenols,and most of these compounds have antioxidant,anti-tumor and other physiological functions.This review comprehensively discusses the bioactive components and functional characteristics of edible fungi(such as antioxidant,anti-aging,hypolipidemic activities,etc.).Then the recent developments and prospect in the high-valued utilization of edible fungi are discussed and summarized.The objective of this review is to improve the understanding of health-promoting properties of edible fungi,and provide reference for the industrial production of edible fungi-based health products. 展开更多
关键词 Edible fungi functional components Processing and utilization High valued utilization
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Bootstrap inference of the skew-normal two-way classification random effects model with interaction
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作者 YE Ren-dao AN Na +1 位作者 LUO Kun LIN Ya 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2022年第3期435-452,共18页
In this paper,we consider the statistical inference problems for the fixed effect and variance component functions in the two-way classification random effects model with skewnormal errors.Firstly,the exact test stati... In this paper,we consider the statistical inference problems for the fixed effect and variance component functions in the two-way classification random effects model with skewnormal errors.Firstly,the exact test statistic for the fixed effect is constructed.Secondly,using the Bootstrap approach and generalized approach,the one-sided hypothesis testing and interval estimation problems for the single variance component,the sum and ratio of variance components are discussed respectively.Further,the Monte Carlo simulation results indicate that the exact test statistic performs well in the one-sided hypothesis testing problem for the fixed effect.And the Bootstrap approach is better than the generalized approach in the one-sided hypothesis testing problems for variance component functions in most cases.Finally,the above approaches are applied to the real data examples of the consumer price index and value-added index of three industries to verify their rationality and effectiveness. 展开更多
关键词 skew-normal two-way classification random effects model with interaction fixed effect variance component functions BOOTSTRAP generalized approach
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Application of Particle Swarm Optimization to Fault Condition Recognition Based on Kernel Principal Component Analysis 被引量:1
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作者 WEI Xiu-ye PAN Hong-xia HUANG Jin-ying WANG Fu-jie 《International Journal of Plant Engineering and Management》 2009年第3期129-135,共7页
Panicle swarm optimization (PSO) is an optimization algorithm based on the swarm intelligent principle. In this paper the modified PSO is applied to a kernel principal component analysis ( KPCA ) for an optimal ke... Panicle swarm optimization (PSO) is an optimization algorithm based on the swarm intelligent principle. In this paper the modified PSO is applied to a kernel principal component analysis ( KPCA ) for an optimal kernel function parameter. We first comprehensively considered within-class scatter and between-class scatter of the sample features. Then, the fitness function of an optimized kernel function parameter is constructed, and the particle swarm optimization algorithm with adaptive acceleration (CPSO) is applied to optimizing it. It is used for gearbox condi- tion recognition, and the result is compared with the recognized results based on principal component analysis (PCA). The results show that KPCA optimized by CPSO can effectively recognize fault conditions of the gearbox by reducing bind set-up of the kernel function parameter, and its results of fault recognition outperform those of PCA. We draw the conclusion that KPCA based on CPSO has an advantage in nonlinear feature extraction of mechanical failure, and is helpful for fault condition recognition of complicated machines. 展开更多
关键词 particle swarm optimization kernel principal component analysis kernel function parameter feature extraction gearbox condition recognition
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Concepts of Safety Critical Systems Unification Approach &Security Assurance Process
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作者 Faisal Nabi Jianming Yong +3 位作者 Xiaohui Tao Muhammad Saqib Malhi Umar Mahmood Usman Iqbal 《Journal of Information Security》 2020年第4期292-303,共12页
The security assurance of computer-based systems that rely on safety and security</span><span style="font-family:'Minion Pro Capt','serif';"> </span><span style="fon... The security assurance of computer-based systems that rely on safety and security</span><span style="font-family:'Minion Pro Capt','serif';"> </span><span style="font-family:Verdana;">assurance, such as consistency, durability, efficiency and accessibility, require or need resources. This target</span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;"> the System-of-Systems (SoS) problems with the exception of difficulties and concerns that apply similarly to subsystem interactions on a single system and system-as-component interactions on a large information</span><span style="font-family:'Minion Pro Capt','serif';"> </span><span style="font-family:Verdana;">system. This research addresses security and information assurance for safety-critical systems, where security and safety </span><span style="font-family:Verdana;">are</span><span style="font-family:Verdana;"> addressed before going to actual implementation/development phase for component-based systems. For this purpose, require a conceptual idea or strategy that deals with the application logic security assurance issues. This may explore the vulnerability in single component or a reuse of specification in existing logic in component-based system. Keeping in view this situation, we have defined seven concepts of security assurance and security assurance design strategy for safety-critical systems. 展开更多
关键词 System Security Assurance of Component Function Safety-Critical Software Software Assurance
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Testing for Error Correlation in Semi-Functional Linear Models
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作者 YANG Bin CHEN Min ZHOU Jianjun 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2023年第4期1697-1716,共20页
Existing methods for analyzing semi-functional linear models usually assumed that random errors are not serially correlated or serially correlated with the known order.However,in some applications,these assumptions on... Existing methods for analyzing semi-functional linear models usually assumed that random errors are not serially correlated or serially correlated with the known order.However,in some applications,these assumptions on random errors may be unreasonable or questionable.To this end,this paper aims at testing error correlation in a semi-functional linear model(SFLM).Based on the empirical likelihood approach,the authors construct an empirical likelihood ratio statistic to test the serial correlation of random errors and identify the order of autocorrelation if the serial correlation holds.The proposed test statistic does not need to estimate the variance as it is data adaptive and possesses the nonparametric version of Wilks'theorem.Simulation studies are conducted to investigate the performance of the proposed test procedure.Two real examples are illustrated by the proposed test method. 展开更多
关键词 Empirical likelihood error correlation functional principal component analysis semifunctional linear model spline estimation Wilks'theorem
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Modeling and prediction of children’s growth data via functional principal component analysis 被引量:8
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作者 HU Yu HE XuMing +1 位作者 TAO Jian SHI NingZhong 《Science China Mathematics》 SCIE 2009年第6期1342-1350,共9页
We use the functional principal component analysis(FPCA) to model and predict the weight growth in children.In particular,we examine how the approach can help discern growth patterns of underweight children relative t... We use the functional principal component analysis(FPCA) to model and predict the weight growth in children.In particular,we examine how the approach can help discern growth patterns of underweight children relative to their normal counterparts,and whether a commonly used transformation to normality plays any constructive roles in a predictive model based on the FPCA.Our work supplements the conditional growth charts developed by Wei and He(2006) by constructing a predictive growth model based on a small number of principal components scores on individual's past. 展开更多
关键词 EIGENFUNCTION functional principal component analysis LMS method growth curve Primary 62H25 Secondary 62P10
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Statistical inference in the partial functional linear expectile regression model 被引量:1
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作者 Juxia Xiao Ping Yu +1 位作者 Xinyuan Song Zhongzhan Zhang 《Science China Mathematics》 SCIE CSCD 2022年第12期2601-2630,共30页
As extensions of means, expectiles embrace all the distribution information of a random variable.The expectile regression is computationally friendlier because the asymmetric least square loss function is differentiab... As extensions of means, expectiles embrace all the distribution information of a random variable.The expectile regression is computationally friendlier because the asymmetric least square loss function is differentiable everywhere. This regression also enables effective estimation of the expectiles of a response variable when potential explanatory variables are given. In this study, we propose the partial functional linear expectile regression model. The slope function and constant coefficients are estimated by using the functional principal component basis. The convergence rate of the slope function and the asymptotic normality of the parameter vector are established. To inspect the effect of the parametric component on the response variable, we develop Wald-type and expectile rank score tests and establish their asymptotic properties. The finite performance of the proposed estimators and test statistics are evaluated through simulation study. Results indicate that the proposed estimators are comparable to competing estimation methods and the newly proposed expectile rank score test is useful. The methodologies are illustrated by using two real data examples. 展开更多
关键词 expectile regression functional principal component analysis Wald-type test expectile rank score test HETEROSCEDASTICITY
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Estimation of partial derivative functionals with application to human mortality data analysis 被引量:1
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作者 Tao Zhang Zhaohai Li +1 位作者 Aiyi Liu Qingzhao Zhang 《Science China Mathematics》 SCIE CSCD 2021年第9期2117-2140,共24页
To better describe and understand the time dynamics in functional data analysis,it is often desirable to recover the partial derivatives of the random surface.A novel approach is proposed based on marginal functional ... To better describe and understand the time dynamics in functional data analysis,it is often desirable to recover the partial derivatives of the random surface.A novel approach is proposed based on marginal functional principal component analysis to derive the representation for partial derivatives.To obtain the Karhunen-Lo`eve expansion of the partial derivatives,an adaptive estimation is explored.Asymptotic results of the proposed estimates are established.Simulation studies show that the proposed methods perform well in finite samples.Application to the human mortality data reveals informative time dynamics in mortality rates. 展开更多
关键词 bivariate functional data functional principal component analysis MORTALITY partial derivatives
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Rank-Based Test for Partial Functional Linear Regression Models 被引量:1
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作者 XIE Tianfa CAO Ruiyuan YU Ping 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2020年第5期1571-1584,共14页
This paper investigates the hypothesis test of the parametric component in partial functional linear regression models.Based on a rank score function,the authors develop a rank test using functional principal componen... This paper investigates the hypothesis test of the parametric component in partial functional linear regression models.Based on a rank score function,the authors develop a rank test using functional principal component analysis,and establish the asymptotic properties of the resulting test under null and local alternative hypotheses.A simulation study shows that the proposed test procedure has good size and power with finite sample sizes.The authors also present an illustration through fitting the Berkeley Growth Data and testing the effect of gender on the height of kids. 展开更多
关键词 Asymptotic normality functional principal component analysis Karhunen-loève expansion local alternative hypothesis rank regression
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