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Multiple Change Points Detection in High-Dimensional Multivariate Regression

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Journal of Systems Science & Complexity 2022年第6期35卷 2278-2301页

作者： MA Xiaoyan zhou qin ZI Xuemin School of Statistics and Data Science LPMC and KLMDASRNankai UniversityTianjin 300071China School of Mathematics and Statistics Jiangsu Normal UniversityXuzhou 221116China School of Science Tianjin University of Technology and EducationTianjin 300222China

This paper considers the problem of detecting structural changes in a high-dimensional regression setting. The structural parameters are subject to abrupt changes of unknown magnitudes at unknown locations. The authors propose a new procedure that minimizes a penalized least-squares loss function via a dynamic programming algorithm for estimating the locations of change points. To alleviate the computational burden, the authors adopt a prescreening procedure by eliminating a large number of irrelevant points before implementing estimation procedure. The number of change points is determined via Schwarz’s information criterion. Under mild assumptions, the authors establish the consistency of the proposed estimators, and further provide error bounds for estimated parameters which achieve almost-optimal rate. Simulation studies show that the proposed method performs reasonably well in terms of estimation accuracy, and a real data example is used for illustration.

关键词： Consistency dynamic programming low-rank structure multi-task learning nuclear norm

Screening-Assisted Dynamic Multiple Testing with False Discovery Rate Control

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Journal of Systems Science & Complexity 2023年第2期36卷 716-754页

作者： MUSHTAQ Iram zhou qin ZI Xuemin School of Statistics and Data Science LPMC and KLMDASRNankai UniversityTianjin 300071China School of Mathematics and Statistics Jiangsu Normal UniversityXuzhou 221116China School of Science Tianjin University of Technology and EducationTianjin 300350China

In the era of big data,high-dimensional data always arrive in streams,making timely and accurate decision *** has become particularly important to rapidly and sequentially identify individuals whose behavior deviates from the *** at identifying as many irregular behavioral patterns as possible,the authors develop a large-scale dynamic testing system in the framework of false discovery rate(FDR)*** fully exploiting the sequential feature of datastreams,the authors propose a screening-assisted procedure that filters streams and then only tests streams that pass the filter at each time point.A data-driven optimal screening threshold is derived,giving the new method an edge over existing *** some mild conditions on the dependence structure of datastreams,the FDR is shown to be strongly controlled and the suggested approach for determining screening thresholds is asymptotically *** studies show that the proposed method is both accurate and powerful,and a real-data example is used for illustrative purpose.

关键词： Change-point false discovery rate high-dimensional datastreams large-scale inference sequential analysis weak dependence structure

Influence of sea-land breeze on the formation and dissipation of severe dense fog and its burst reinforcement in the Yellow Sea coastal area,China

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Science China Earth Sciences 2024年第2期67卷 432-449页

作者： ya GAO Duanyang LIU Shuqi yaN Wenjun zhou Hongbin WANG Fan ZU qin MEI Chuanxiang YI Ye SHENG Key Laboratory of Transportation Meteorology of China Meteorological Administration Nanjing210041China yancheng Meteorological Bureau Yancheng224000China Nanjing Joint Institute for Atmospheric Sciences Nanjing210041China Key Laboratory of Disaster Weather Chinese Academy of Meteorological SciencesBeijing100086China

Based on the global reanalysis data of the National Centers for Environmental Prediction(NCEP)/National Center for Atmospheric Research,the surface meteorological observation data,sounding data and satellite observation data,this paper comprehensively analyzes the evolution process and formation mechanism of a persistent severe dense fog process occurred on February 15–17,2015 in yancheng,eastern *** the numerical simulation experiment of Weather Research and Forecast(WRF)model,we further analyze the impact of sea-land breeze on the formation and burst reinforcement of *** show that the precipitation caused by the southwesterly airflow in front of the upper-level trough and the low-pressure inverted trough are conducive to the formation of early rain fog,while the nighttime clear radiance under the control of surface cold high and the infiltration of weak cold advection are conducive to the formation and development of later radiation-advection *** WRF model simulates the fog evolution process,which is basically consistent with the actual fog area,and the simulation results are credible to a certain *** simulation results show that the establishment of sea breeze has an advection cooling effect on the near surface layer,which is conducive to the formation and development of the inversion layer on the near surface,providing stable stratification conditions for the formation and burst reinforcement of *** one hand,the strengthening of sea breeze circulation can continuously transport water vapor to the study *** the other,the occurrence of ultra-low level jet is favorable for the accumulation of low-level water *** the same time,the inversion intensity further strengthens,which is in favor of the burst reinforcement and long-term maintenance of fog.

关键词： Radiation-advection fog Sea-land breeze Atmospheric boundary layer Fog burst reinforcement WRF model

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What are the keys to influence the life satisfaction of eco-migrants in the northern foot of the Qilian Mountains?A test based on the livelihood risk interaction

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Journal of Mountain Science 2022年第11期19卷 3227-3245页

作者： WANG ya zhou Li-hua Key Laboratory of Desert and Desertification Northwest Institute of Eco-environment and ResourcesChinese Academy of SciencesLanzhou 730000China Institutes of Science and Development Chinese Academy of SciencesBeijing 100190China School of public policy and management University of Chinese Academy of SciencesBeijing 100049China

Eco-migrants'ability to adapt to livelihood risks and their satisfaction with lives directly affect the ecological and economic benefits of ecological migration *** formulate an effective livelihood risk prevention system and welfare guarantee mechanism,we took the ecomigrants in Wuwei City as an example,developed an integrated analytical framework for life satisfaction and employed linear regression models to identify the interactions between livelihood risk and life *** findings indicate that 94.66%of eco-migrants in Wuwei City are threatened by livelihood risks after *** living expenses,poor quality of redistributed production goods,and re-poverty constitute the main *** risk multiplicity index is *** cultural types,there are no significant differences in regions and livelihoods.A total of 55.73%of eco-migrants are satisfied with their lives,with the Liangzhou district scoring the *** for satisfaction with development potential and public services,no significant intergroup differences were found among regions and livelihood ***-migrant's life satisfaction is significantly affected by livelihood ***-migrants'satisfaction with living income,social integration,farmer-friendly policies and overall life is negatively affected by the risk of repoverty and inadequate social *** ecomigrant's satisfaction with development potential and community construction is not influenced by one type of risk alone,but the interaction between risks has a strong *** interaction of welfare risks with economic risks and policy risks will balance and weaken the adverse effects of a single risk on those elements in the economic and policy *** study offers novel ideas for rural revitalization,hollow governance,and well-being assurance.

关键词： Eco-migrant Livelihood risk Life satisfaction Northern foot of Qilian Mountain

Numerical analysis of a Neumann boundary control problem with a stochastic parabolic equation

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Science China Mathematics 2023年第9期66卷 2133-2156页

作者： qin zhou Binjie Li School of Mathematics Sichuan UniversityChengdu 610064China School of Mathematics&Information China West Normal UniversityNanchong 637002China

We analyze the discretization of a Neumann boundary control problem with a stochastic parabolic equation, where additive noise occurs in the Neumann boundary condition. The convergence is established for general filtr... 详细信息

关键词： Neumann boundary control stochastic parabolic equation Q-Wiener process boundary noise discretization convergence

Retrieving Soil Water Contents from Soil Temperature Measurements by Using Linear Regression

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Advances in Atmospheric Sciences 2003年第6期20卷 849-858页

作者： qin XU Binbin zhou NOAA NationalSevereStormsLaboratoryNormanOklahomaUSA NOAAJNWSflNationalCentersforEnvironmentalPrediction CampSpringsMarylandUSA

A simple linear regression method is developed to retrieve daily averaged soil water content from diurnal variations of soil temperature measured at three or more depths. The method is applied to Oklahoma Mesonet soil temperature data collected at the depths of 5, 10, and 30 cm during 11–20 June 1995. The retrieved bulk soil water contents are compared with direct measurements for one pair of nearly collocated Mesonet and ARM stations and also compared with the retrievals of a previous method at 14 enhanced Oklahoma Mesonet stations. The results show that the current method gives more persistent retrievals than the previous method. The method is also applied to Oklahoma Mesonet soil temperature data collected at the depths of 5, 25, 60, and 75 cm from the Norman site during 20–30 July 1998 and 1–31 July 2000. The retrieved soil water contents are verified by collocated soil water content measurements with rms differences smaller than the soil water observation error (0.05 m3 m−3). The retrievals are found to be moderately sensitive to random errors (±0.1 K) in the soil temperature observations and errors in the soil type specifications.

关键词： retrieval soil water content

Simple and Efficient Procedure for Highly Diastereoselective Synthesis of trans- 1,1-Disubstituted-2,6-diarylcyclohexane-4-ones

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Chemical Research in Chinese Universities 2013年第6期29卷 1115-1118页

作者： YU ya-qin WANG Zhong-liang Tianjin Key Laboratory of Water Resources and Environment Tianjin Normal UniversityTianjin 300387 P.R.China State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of Sciences Guiyang 550002 P.R.China

A simple and efficient method has been developed for highly diastcreoselective synthesis of trans-1,1-disubstituted-2,6-diarylcyclohexane-4-ones from dibenzalacetone and malononitril with trans-1,2-diaminocyclohexane as catalyst. The substrate 1,5-diaryl-1,4-pentadien-3-ones and active methylene compounds proceeded to give the products with good to excellent yield within a short time.

关键词： Substituted cyclohexanone Double Michael addition Malononitrile

Temperature effect on photolysis decomposing of perfluorooctanoic acid

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Journal of Environmental Sciences 2016年第4期28卷 126-133页

作者： Tiliang Zhang Gang Pan qin zhou Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

Perfluorooctanoic acid（PFOA）is recalcitrant to degrade and ***,the effect of temperature on the photolytic decomposition of PFOA was *** decomposition of PFOA was enhanced from 34% to 99% in 60 min of exposure when the temperature was increased from 25 to 85℃ under UV light（201–600 nm）.The limited degree of decomposition at 25℃ was due to low quantum yield,which was increased by a factor of 12 at 85℃.Under the imposed conditions,the defluorination ratio increased from 8% at 25℃ to 50% at85℃ in 60 *** of perfluorinated carboxylic acids（PFCAs,C7–C5）,PFCAs（C4–C3）and TFA（trifluoroacetic acid,C2）accelerated and attained a maximum within 30 to 90 min at 85℃.However,these reactions did not occur at 25℃ despite extended irradiation to180 *** was decomposed in a step-wise process by surrendering one *** each cyclical process,increased temperature enhanced the quantum yields of irradiation and reactions between water molecules and intermediates *** energy consumption for removing eachμmol of PFOA was reduced from 82.5 k J at 25℃ to 10.9 k J at 85℃ using *** coupled with heat achieved high rates of PFOA degradation and defluorination.

关键词： Perfluorooctanoic acid PFOA Photolysis Temperature effect

Effect of glucose on the soil bacterial diversity and function in the rhizosphere of Cerasus sachalinensis

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Horticultural Plant Journal 2021年第4期7卷 307-317页

作者： Wenjie zhou Xu qin Deguo Lyu Sijun qin College of Horticulture Shenyang Agricultural UniversityShenyang 110866China Small Fruit Institute Eastern Liaoning University/Key Laboratory of Blueberry Breeding and Postharvest HandlingLiaoning ProvinceDandongLiaoning 118003China School of Garden Science and Engineering Shandong Agriculture and Engineering UniversityJinanShandong 250100China

Most cherry orchards in China have low organic carbon content,though carbon is very important for plant *** changes in soil carbon and bacterial diversity were determined after different amounts of 12C-glucose were added to the rhizosphere of Cerasus *** bacteria diversity was measured using high throughput sequencing,and bacteria containing 13C-glucose were identified using DNA-SIP *** results demonstrated that soil microbial biomass carbon(MBC)content and the soil respiratory rate were increased at 3 and 7 days after adding *** soil organic carbon(SOC)content was decreased on the 7th day in the treatment where the added glucose-C was equivalent to the MBC *** content was decreased on the 15th day after adding glucose-C equivalent to five times that of the soil *** to the controls,the relative abundance of taxa at the phylum level displayed no significant change in the treatments with glucose-C added as 10%and equal amount of soil MBC 3–30 days after ***,the relative abundance of Proteobacteria increased significantly in the treatment with the addition of glucose-C equivalent to five times of soil *** main changes were observed in the bacteria in several genera including A4,Flavisolibacter,Aquicella,and Candidatus ***-SIP results indicated that the relative abundance of the Proteobacteria and Pseudomonas was the highest;these were the primary bacteria phylum and genus,respectively,from day 3 to day *** conclusion,the changing pattern demonstrated that with the addition of more glucose,the range of the bacterial communities changed *** and Pseudomonas may be the bacteria promoting priming effect.

关键词： Cerasus sachalinensis Soil respiration Soil organic carbon High throughput sequencing DNA-SIP Priming effect