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Joint modeling of longitudinal proportional measurements and survival time with a cure fraction

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Science China Mathematics 2016年第12期59卷 2427-2442页

作者： song Hui PENG YingWei TU DongSheng School of Mathematical Sciences Dalian University of Technology Departments of Public Health Sciences & Mathematics and Statistics Queen's UniversityKingston Canadian Cancer Trials Group Queen's UniversityKingston

In cancer clinical trials and other medical studies, both longitudinal measurements and data on a time to an event(survival time) are often collected from the same patients. Joint analyses of these data would improve the efficiency of the statistical inferences. We propose a new joint model for the longitudinal proportional measurements which are restricted in a finite interval and survival times with a potential cure fraction. A penalized joint likelihood is derived based on the Laplace approximation and a semiparametric procedure based on this likelihood is developed to estimate the parameters in the joint model. A simulation study is performed to evaluate the statistical properties of the proposed procedures. The proposed model is applied to data from a clinical trial on early breast cancer.

关键词： cure fraction joint model Laplace approximation proportional data simplex distribution survival times

Efficient pairing-based batch anonymous authentication scheme for VANET

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The Journal of China Universities of Posts and Telecommunications 2018年第1期25卷 85-94页

作者： song Cheng Zhang Mingyue Peng Weiping School of Computer Science and Technology Henan Polytechnic University

To solve the efficiency problem of batch anonymous authentication for vehicular Ad-hoc networks （VANET） , an improved scheme is proposed by using bilinear pairing on elliptic curves. The signature is jointly generated by roadside unit （RSU） node and vehicle, thus reducing the burden of VANET certification center and improving the authentication efficiency, and making it more difficult for attacker to extract the key. Furthermore, under random oracle model （ROM） security proof is provided. Analyses show that the proposed scheme can defend against many kinds of security problems, such as anonymity, man-in-the-middle （ MITM ） attack, collusion attack, unforgeability, forward security and backward security etc. , while the computational overheads are significantly reduced and the authentication efficiency is effectively improved. Therefore, the scheme has great theoretical significance and application value under computational capability constrained Internet of things （IoT） environments.

关键词： bilinear pairing anonymous authentication privacy protection vehicular Ad-hoc networks random oracle model

Traffic flow prediction based on BILSTM model and data denoising scheme

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Chinese Physics B 2022年第4期31卷 191-200页

作者： Zhong-Yu Li Hong-Xia ge Rong-Jun Cheng Faculty of Maritime and Transportation Ningbo UniversityNingbo 315211China Jiangsu Provincial Collaborative Innovation Center for Modern Urban Traffic Technologies Nanjing 210096China National Traffic Management Engineering and Technology Research Center Ningbo University Subcenter Ningbo 315211China

Accurate prediction of road traffic flow is a significant part in the intelligent transportation *** prediction can alleviate traffic congestion,and reduce environmental *** the management department,it can make effective use of road *** individuals,it can help people plan their own travel paths,avoid congestion,and save *** to complex factors on the road,such as damage to the detector and disturbances from environment,the measured traffic volume can contain *** the influence of noise on traffic flow prediction is a piece of very important ***,in this paper we propose a combination algorithm of denoising and BILSTM to effectively improve the performance of traffic flow *** the same time,three denoising algorithms are compared to find the best combination *** this paper,the wavelet(WL) denoising scheme,the empirical mode decomposition(EMD) denoising scheme,and the ensemble empirical mode decomposition(EEMD) denoising scheme are all introduced to suppress outliers in traffic flow *** addition,we combine the denoising schemes with bidirectional long short-term memory(BILSTM)network to predict the traffic *** data in this paper are cited from performance measurement system(PeMS).We choose three kinds of road data(mainline,off ramp,on ramp) to predict traffic *** results for mainline show that data denoising can improve prediction ***,prediction accuracy of BILSTM+EEMD scheme is the highest in the three methods(BILSTM+WL,BILSTM+EMD,BILSTM+EEMD).The results for off ramp and on ramp show the same performance as the results for *** is indicated that this model is suitable for different road sections and long-term prediction.

关键词： traffic flow prediction bidirectional long short-term memory network data denoising

Temperature-induced deformation of CRTS II slab track and its effect on track dynamical properties

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Science China(Technological Sciences) 2014年第10期57卷 1917-1924页

作者： song XiaoLin ZHAO ChunFa ZHU XiaoJia State Key Laboratory of Traction Power Southwest Jiaotong University

Two finite-element models of the CRTS II slab track are presented to simulate temperature-induced deformations of the concrete track slab with no deterioration or with a deteriorated cement asphalt mortar(CAM).One model,which considers the fully bonding interface between the slab and the CAM layer,could applied to a track that is in good condition;the other model uses cohesive zone elements to simulate the deteriorated CAM with some possible interfacial separation and *** both of the models,temperature-induced warp deformations of track under various temperature loads are *** influence of temperature deformation on the dynamic properties of the track is analyzed based on the train-track coupled *** results show that the deteriorated CAM layer can significantly increase temperature deformations of a CRTS II track slab,which would produce tiny rail *** are clear differences between the deformation shapes of the track slabs that have an inseparable mortar layer and those have a separable mortar *** track slab with a deteriorated mortar layer showed more open curl distortion than the track slab in good *** dynamical response index of the slab track is intensified to a certain level due to the temperature deformation;with an increase of the train speed,the track dynamical responses increased ***,rail irregularities due to the temperature deformations are very *** if a track is exposed to extreme temperature loads and the mortar layer is deteriorated,temperature deformation can have a negligible effect on the track’s dynamical properties.

关键词： high-speed railway temperature deformation slab track dynamical properties

A New Acylated Flavonoid from Anaphalis aureo-punctata

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Chinese Chemical Letters 2003年第1期14卷 66-67页

作者： yan Qi WU Shuo LI ya LI Yu LI National Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhou 730000

A new acylated flavonoid glycoside, 3-O-kaempferol-3-O-acetyl-6-O-(p-coumaroyl)-- D-glucopyranoside 1 was isolated from the whole plant of Anaphalis aureo-punctata. The structure was established by spectral methods.

关键词： Anaphalis aureo-punctata flavonoid 3-O-kaempferol-3-O-acetyl-6-O-(p-coumaroyl)- -D-glucopyranoside.

Correlations Between Foliar Stable Carbon Isotope Composition and Environmental Factors in Desert Plant Reaumuria soongorica （Pall.） Maxim.

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Journal of Integrative Plant Biology 2005年第9期47卷 1065-1073页

作者： Jian-Ying MA Tuo CHEN Wei-ya QIANG Gang WANG School of Life Sciences Lanzhou University Lanzhou 730000 China Cold and Arid Environmental and Engineering Research Institute the Chinese Academy of Sciences Lanzhou 730000 China

Leaves of 407 individuals of Reaumuria soongorica （Pall.） Maxim. collected from the major distribution areas were measured to investigate the distribution characteristics of the stable carbon isotope in this desert plant, as well as correlations between δ^13C values and environmental factors. Results showed that δ^13C values in R. soongorica ranged from -22.77‰ to -29.85‰ and that the mean δ^13C value （-26.52‰） was higher than a previously reported δ^13C value for a different desert ecosystem. This indicates that R. soongorica belongs to the C3 photosynthetic pathway and has higher water use efficiency than other species. The correlations between δ^13C values and environmental factors demonstrated that the foliar δ^13C values in R. soongorica increased significantly with decreasing mean annual precipitation and mean relative humidity, and decreased with decreasing duration of sunshine and evaporation. The spatial distribution trend of δ^13C values in R. soongorica was not obvious and there was no significant correlation between the δ^13C values and mean annual temperature. We conclude that different distribution trends in δ^13C values for R. soongorica were likely caused by stomatal limitation rather than by nutrient-related changes in photosynthetic efficiency and that precipitation played an important role in the wide distribution range of R. soongorica. This pattern of δ^13C values for R. soongorica reinforced that it is a super-xerophil in terms of its adaptive strategies to a desert environment.

关键词： carbon isotope composition desert plant meteorological factor Reaumuria soongorica.

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Revised BDS test

Applied Mathematics(A Journal of Chinese Universities) 2024年第4期39卷 721-749页

作者： LUO Wen-ya BAI Zhi-dong HU Jiang WANG Chen School of Data Science Zhejiang University of Finance and EconomicsHangzhou 310018China

In this paper,we focus on the BDS test,which is a nonparametric test of ***,the null hypothesis H0 of it is that {u_(t)} is i.i.d.(independent and identically distributed),where {u_(t)} is a random *** BDS test is widely used in economics and finance,but it has a weakness that cannot be ignored:over-rejecting H0 even if the length T of {u_(t)} is as large as(100;2000).To improve the over-rejection problem of BDS test,considering that the correlation integral is the foundation of this test,we not only accurately describe the expectation of the correlation integral under H_(0),but also calculate all terms of the asymptotic variance of the correlation integral whose order is O(T^(-1))and O(T^(-2)),which is essential to improve the finite sample performance of BDS *** on this,we propose a revised BDS(RBDS)test and prove its asymptotic normality under *** RBDS test not only inherits all the advantages of BDS test,but also effectively corrects the over-rejection problem of it,which can be fully confirmed by the simulation results we ***,based on the simulation results,we find that similar to BDS test,RBDS test would also be affected by the parameter estimations of the ARCH-type model,resulting in size distortion,but this phenomenon can be alleviated by the logarithmic transformation preprocessing of the estimate residuals of the ***,through some actual datasets that have been demonstrated to fit well with ARCH-type models,we also compared the performance of BDS test and RBDS test in evaluating the goodness-of-fit of the model in empirical problem,and the results reflect that,under the same condition,the performance of the RBDS test is more encouraging.

关键词： independence the correlation integral over-rejection BDS test

Design of thiol-containing amino acids for native chemical ligation at non-Cys sites

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Chinese Chemical Letters 2013年第4期24卷 265-269页

作者： Qiao-Qiao He ge-Min Fang Lei Liu Tsinghua-Peking Center for Life Sciences Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology(Ministry of Education)Department of ChemistryTsinghua University High Magnetic Field Laboratory Chinese Academy of Sciences

Protein chemical synthesis usually relies on the use of native chemical ligation that couples peptide thioester with a Cys-peptide. A limitation of this method is the difficulty of finding an appropriate Cys ligation site in many synthetic targets. To overcome this problem, the ligation-desulfurization approach has been developed. This approach involves the use of a thiol-containing amino acid as the ligation partner. After the sequence assembly is completed, the thiol group is removed through a desulfurization reaction to generate the standard amino acids. Currently this strategy has been applied to the ligations at a number of amino acids including Ala, Phe, Val, Lys, Thr, Leu, Pro and Gin. The present article reviews the design and svnthesis of these thiol-containing amino acids for native chemical libation at non-Cys sites.

关键词： Protein chemical synthesisNative chemical ligationDesulfurization

Transcriptome analysis of the symbiosis-related genes between Funneliformis mosseae and Amorpha fruticosa

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Journal of Forestry Research 2019年第2期30卷 483-495页

作者： Xuan Liu Mingguo Jiang Fuqiang song Heilongjiang University GuangXi University for Nationalities

Arbuscular mycorrhizal fungi(AMF) can colonize and form associations with the roots of Amorpha fruticosa L.(desert false indigo). Various genes are induced during the symbiotic process. In this study, de novo transcriptome sequencing using RNA-seq was conducted for the first time for a comprehensive analysis of AMF-A. fruticosa symbionts at the transcript level. We obtained 12 G of raw data from illumina sequencing and recovered 115,786 unigenes with an average length of547 bp, among them 41,848 of significance. A total of2460 diffexpression genes were identified, including 1579 down-regulated and 881 up-regulated genes. A threshold for false discovery rate of \ 0.001 and fold change of [ 1 determined significant differences in gene *** these criteria, we screened 285 significant differentially expressed genes, of which 82 were up-regulated and203 down-regulated. The 82 up-regulated genes were classified according to their functions and assigned into seven categories: stress and defense, metabolism, signaling transduction, protein folding and degradation, energy,protein synthesis, and transcription. The 203 down-regulated genes were screened according to fold change [ 2,and 50 highly significant down-regulated genes were obtained related to stress and defense. The results of this study will provide a useful foundation for further investigation on the metabolic characteristics and molecular mechanisms of AMF associations with leguminous woody shrubs.

关键词： Amorpha fruticose Arbuscular mycorrhizal fungi RNA-seq Symbiosis-related gene Quantitative real-time PCR