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Frontiers of Mathematics in China 2021年第3期16卷 825-856页

作者： Xiaowei YANG Shuang SONG huiming zhang School of Mathematics and Statistics Chaohu UniversityChaohuHefei238024China Center for Statistical Science Tsinghua UniversityBeijing100084China Department of Industrial Engineering Tsinghua UniversityBeijing100084China Department of Mathematics University of MacaoTaipa MacaoChina UMacao Zhuhai Research Institute Zhuhai519000China

We study the law of the iterated logarithm (LIL) for the maximum likelihood estimation of the parameters (as a convex optimization problem) in the generalized linear models with independent or weakly dependent (ρ-mixing) responses under mild conditions. The LIL is useful to derive the asymptotic bounds for the discrepancy between the empirical process of the log-likelihood function and the true log-likelihood. The strong consistency of some penalized likelihood-based model selection criteria can be shown as an application of the LIL. Under some regularity conditions, the model selection criterion will be helpful to select the simplest correct model almost surely when the penalty term increases with the model dimension, and the penalty term has an order higher than O(log log n) but lower than O(n). Simulation studies are implemented to verify the selection consistency of Bayesian information criterion.

关键词： Generalized linear models(GLMs) weighted scores method non-natural link function model selection consistency weakly dependent

Synthesis of ZSM-5/MOR Co-crystalline Zeolite without Template and the Catalytic Application Thereof

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China Petroleum Processing & Petrochemical Technology 2009年第1期11卷 51-57页

作者： zhang huiming Ma Guangwei Shanghai Research Institute of Petrochemical Technology SINOPEC Shanghai 201208

A ZSM-5/MOR co-crystalline zeolite was synthesized without using the template. The physico-chemical properties of the zeolite were characterized by XRD, FT-IR, SEM and TPD and then compared with the co-crystalline zeolite synthesized with a template. Analytical results indicated that they were similar in structure and composition. The influences ofpH value and Si/Al ratio on synthesis were studied. It was found that a high pH value or a low Si/AI ratio could provide better environment for mordenite （MOR） crystallization. The zeolites applied as catalysts in naphtha catalytic cracking for producing ethylene and propylene showed outstanding catalytic performance with the total yield of ethylene and propylene reaching 55 m%. The process could achieve most favorable efficiency when the catalyst contained 5 m% of MOR.

关键词： ZSM-5 mordenite co-crystalline catalytic cracking ethylene propylene

COM-negative binomial distribution： modeling overdispersion and ultrahigh zero-inflated count data

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Frontiers of Mathematics in China 2018年第4期13卷 967-998页

作者： huiming zhang Kai TAN Bo LI School of Mathematical Sciences and Center for Statistical Science Peking UniversityBeijing 100871 China Department ofStatistics University of Kentucky Lexington KY 40508 USA School of Mathematics and Statistics Central China Normal University Wuhan 430079 China

We focus on the COM-type negative binomial distribution with three parameters, which belongs to COM-type （a, b, 0） class distributions and family of equilibrium distributions of arbitrary birth-death process. Besides, we show abundant distributional properties such as overdispersion and underdispersion, log-concavity, log-convexity （infinite divisibility）, pseudo compound Poisson, stochastic ordering, and asymptotic approximation. Some characterizations including sum of equicorrelated geometrically distributed random variables, conditional distribution, limit distribution of COM-negative hypergeometric distribution, and Stein＇s identity are given for theoretical properties. COM- negative binomial distribution was applied to overdispersion and ultrahigh zeroinflated data sets. With the aid of ratio regression, we employ maximum likelihood method to estimate the parameters and the goodness-of-fit are evaluated by the discrete Kolmogorov-Smirnov test.

关键词： Overdispersion zero-inflated data infinite divisibility Stein'scharacterization discrete Kolmogorov-Smirnov test

New discoveries generate new questions about RNA-directed DNA methylation in Arabidopsis

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National Science Review 2017年第1期4卷 10-15页

作者： huiming zhang Jian-Kang Zhu Shanghai Center for Plant Stress Biology and CAS Center for Excellence in Molecular Plant SciencesChinese Academy of Sciences Department of Horticulture and Landscape Architecture Purdue University

Plants can establish de novo DNA methylation via the RNA-directed DNA methylation(RdDM)pathway,which involves a complex array of proteins as well as small interfering RNAs(siRNAs)and scafold *** the canonicalRd DM pathway that is best understood in Arabidopsis,complementary pairing between 24-nt siRNAs and nascent scafold RNAs,together with protein–protein interactions,recruits the protein machinery for DNA methylation.

关键词： DCL RNA DNAmethylation AGO

Impact of the Yellow River capture on the paleoenvironmental changes of Hongze Lake, China

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International Journal of Sediment Research 2023年第4期38卷 503-515页

作者： Hongwu Tang Ming Gao Saiyu Yuan huiming zhang Yang Xiao Fuxin zhang Kun zhang State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Key Laboratory of Hydrologic-Cycle and Hydrodynamic-System of Ministry of Water Resources Hohai University Institute of Water Science and Technology Hohai University

The Yellow River(YR) capture of the Huai River had a profound effect on the landscape evolution,ecology, and social development in China, disrupting the evolution of some vital shallow floodplain *** of the absence of lacustrine sediment provenance analysis, previous studies were inadequate in distinguishing the influence of YR capture on paleoenvironmental changes in these lakes, especially on landscape evolution, redox conditions, lake level changes, and organic productivity. The current study aims to use X-ray fluorescence-core scanning(XRF-CS) and multivariate statistics on a 9.8 m sediment core from Hongze Lake(HZL), China, to analyze the impact of the YR capture on the lake’s paleoenvironmental changes and the sediment provenance simultaneously. High-resolution images, magnetic susceptibility, and XRF-based multi-element data were obtained using a GEOTEK Multi-Sensor Core Logger. The calcium(Ca) content indicates the presence of YR sediment in HZL, given the high Ca content in YR sediment and the identification of mainly exogenous sources of Ca in HZL. The high values of Ca indicate that 48.7% of the sediment in the center of HZL is related to the YR’s incursion. Periods of higher Ca content coincide with periods of higher oxygenation levels of the lake(as indicated by the ratio of manganese to titanium) and lower organic content in the lake sediment(as indicated by the ratio of incoherent to coherent scatter). These analyses reveal that the YR’s capture of HZL significantly increased the lake’s oxygen level. Furthermore, the decrease in the organic content of sediment tends to be the result of the accelerated deposition caused by the YR. The decrease in Ca content coincides with an increase in lake levels(as indicated by magnetic susceptibility). Thus, it can be inferred that the embankment on the eastern side of HZL, built to increase lake storage, has reduced the incursion frequency of the YR.

关键词： Yellow River capture Paleoenvironmental reconstruction XRF-CS Hongze Lake

Compressive properties of aluminum foams by gas injection method

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China Foundry 2012年第3期9卷 215-220页

作者： zhang huiming Chen Xiang Fan Xueliu Li Yanxiang Department of Mechanical Engineering Tsinghua University Beijing 100084 China Key Laboratory for Advanced Materials Processing Technology Ministry of Education Tsinghua University Beijing 100084 China

The compressive properties of aluminum foams by gas injection method are investigated under both quasi-static and dynamic compressive loads in this paper. The experimental results indicate that the deformation of the aluminum foams goes through three stages: elastic deforming, plastic deforming and densification stage, during both the quasi-static and dynamic compressions. The aluminum foams with small average cell size or low porosity have high yield strength. An increase in strain rate can lead to an increase of yield strength. The yield strength of the aluminum foams under the dynamic loading condition is much greater than that under the quasi-static loading condition. Dynamic compressive tests show that a higher strain rate can give rise to a higher energy absorption capacity, which demonstrates that the aluminum foams have remarkable strain rate sensitivity on the loading rate.

关键词： aluminum foam strain rate porosity energy absorption

Solid-State Electrolytes for Lithium-Sulfur Batteries

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第4期35卷 565-577页

作者： zhang huiming Guo Cheng Nuli Yanna Yang Jun Wang Jiulin Shanghai Electrochemical Energy Devices Research Center School of Chemistry and Chemical EngineeringShanghai Jiao Tong University

Secondary lithium-sulfur batteries have attracted extensive attention due to their high energy density,low cost and environment ***,the"shuttle effect"of polysulfides dissolved in liquid electrolytes leads to a decrease of the cell Coulomb efficiency(CE).Therefore,researchers have used solid electrolytes instead of traditional liquid electrolytes and separators to suppress the"shuttle effect"of polysulfides and the growth of lithium *** progress in electrolytes for solid-state lithium-sulfur batteries including solid-state polymer,inorganic,and composite electrolytes to solve the issues is summarized.

关键词： lithium-sulfur batteries solid-state polymer electrolytes inorganic electrolytes composite electrolytes

The Mid-Long Term Outcome of Breast-Conserving Patients with Different Ages

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Clinical oncology and cancer researeh 2009年第4期6卷 250-255页

作者： huiming zhang XiangWang Baoning zhang Department of Abdominal Surgery CancerHospital Chinese Academy of Medical Sci-ences Peking Union Medical College Beijing100021. China.

OBJECTIVE Breast-conserving surgery has been a standard treatment for relatively small size of breast cancer. Younger breast cancer patients have more desire to conserve their breasts. This study was to investigate the clinicopathological characteristics and prognosis of younger breast cancer patients who received breastconserving treatment in China. METHODS The data of 232 breast cancer patients who received breast-conserving treatment in Cancer Hospital of Chinese Academy of Medical Science from January Ist, 1999 to December 31st, 2005, were collected and retrospectively analyzed. According to the age, the patients were divided into 2 groups： younger group （age ≤ 35 at the time of diagnosis） and elder group （age 〉35）. The clinical features of the patients in the 2 groups were compared, and their clinical characteristics, recurrence, metastasis and survival status were summarized. RESULTS In the 232 cases, younger patients accounted for 15.9% （37/232）, the elder 84.1% （195/232）. By December 2008, the median time of follow-up was 54 months （ranging from 2 months to 118 months）. Two patients （5.41% , 2/37） in the younger group and 5 patients （2.56% 5/195） in the elder group died. The 5-year overall survival rate （OS） in the younger and elder groups was 96.08% and 97.19%, respectively （X2= 0.69, P = 0.4066）. Local recurrence （LR） or distant metastasis （DM） presented in 5 patients （5/37, 13.51%） in younger group. LR or DM presented in 10 patients （10/195, 5.13%） in elder group. The 5-year disease-free survival （DFS） rate in the younger and elder groups was 82.58% and 95.52%, respectively （X2 = 4.02, P = 0.0451）. Lymph node status and the age of 35 years old or younger were the prognosis factors affecting the DFS of patients who received breast-conserving treatment （OR = 3.467, 95%CI： 1.048-11.472, P 〈0.05; OR = 0.245, 95%CI： 0.069-0.863, P 〈 0.05）. Lymph node status was the only prognostic factor affecting the DFS of younger group patients （OR = 7.357, 95%CI： 1.030-52.

关键词： breast neoplasms breast-conserving treatment,age clinical characteristics treatment prognosis.

WEIGHTED LASSO ESTIMATES FOR SPARSE LOGISTIC REGRESSION:NON-ASYMPTOTIC PROPERTIES WITH MEASUREMENT ERRORS

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Acta Mathematica Scientia 2021年第1期41卷 207-230页

作者： Huamei HUANG Yujing GAO huiming zhang Bo LI Department of Statistics and Finance University of Science and Technology of ChinaHefei 230026China Guanghua School of Management Peking UniversityBeijing 100871China School of Mathematical Sciences Peking UniversityBeijing 100871China School of Mathematics and Statistics Central China Normal UniversityWuhan 430079China

For high-dimensional models with a focus on classification performance,the?1-penalized logistic regression is becoming important and ***,the Lasso estimates could be problematic when penalties of different coefficients are all the same and not related to the *** propose two types of weighted Lasso estimates,depending upon covariates determined by the Mc Diarmid *** sample size n and a dimension of covariates p,the finite sample behavior of our proposed method with a diverging number of predictors is illustrated by non-asymptotic oracle inequalities such as the?1-estimation error and the squared prediction error of the unknown *** compare the performance of our method with that of former weighted estimates on simulated data,then apply it to do real data analysis.

关键词： logistic regression weighted Lasso oracle inequalities high-dimensional statistics measurement error

Concentration Inequalities for Statistical Inference

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Communications in Mathematical Research 2021年第1期37卷 1-85页

作者： huiming zhang Song Xi Chen School of Mathematical Sciences Peking UniversityBeijing 100871P.R.China Guanghua School of Management Peking UniversityBeijing 100871P.R.China Center for Statistical Sciences Peking UniversityBeijing 100871P.R.China Department of Mathematics Faculty of Science and TechnologyUniversity of MacaoMacaoP.R.China

This paper gives a review of concentration inequalities which are widely employed in non-asymptotical analyses of mathematical statistics in awide range of settings,fromdistribution-free to distribution-dependent,from sub-Gaussian to sub-exponential,sub-Gamma,and sub-Weibull random variables,and from the mean to the maximum *** review provides results in these settings with some fresh new *** the increasing popularity of high-dimensional data and inference,results in the context of high-dimensional linear and Poisson regressions are also *** aim to illustrate the concentration inequalities with known constants and to improve existing bounds with sharper constants.

关键词： Constants-specified inequalities sub-Weibull randomvariables heavy-tailed distributions high-dimensional estimation and testing finite-sample theory randommatrices