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An Alternating Direction Method of Multipliers for MCP-penalized Regression with High-dimensional Data

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Acta Mathematica Sinica,English Series 2018年第12期34卷 1892-1906页

作者： yue Yong SHI yu Ling JIAO Yong xiu CAO Yan Yan LIU School of Economics and Management China University of Geosciences Wuhan 430074 P. R. China Center for Resources and Environmental Economic Research China University of Geosciences Wuhan 430074 P. R. China School of Statistics and Mathematics Zhongnan University of Economics and Law Wuhan 430073 P. R. China School of Mathematics and Statistics Wuhan University Wuhan 430072 P. R. China

The minimax concave penalty （MCP） has been demonstrated theoretically and practical- ly to be effective in nonconvex penalization for variable selection and parameter estimation. In this paper, we develop an efficient alternating direction method of multipliers （ADMM） with continuation algorithm for solving the MCP-penalized least squares problem in high dimensions. Under some mild conditions, we study the convergence properties and the Karush-Kuhn-Tucker （KKT） optimality con- ditions of the proposed method. A high-dimensional BIC is developed to select the optimal tuning parameters. Simulations and a real data example are presented to illustrate the efficiency and accuracy of the proposed method.

关键词： Alternating direction method of multipliers coordinate descent continuation high-dimen-sional BIC minimax concave penalty penalized least squares

贵州某医高专在校学生自卑感现状及其与应对方式的相关性研究

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黔南民族医专学报 2024年第2期37卷 195-199页

作者：王晓鹏陶雯秦素霞华灿城苏娟余跃生黔南民族医学高等专科学校贵州都匀558013

目的:了解医学生自卑感现状及其与应对方式的相关性,为大学生心理健康教育和自卑心理干预提供参考依据。方法:采用应对方式问卷、自卑感量表和自制的一般资料调查表,对贵州某医高专在校学生的自卑感和应对方式进行问卷调查,使用SPSS22.... 详细信息

目的:了解医学生自卑感现状及其与应对方式的相关性,为大学生心理健康教育和自卑心理干预提供参考依据。方法:采用应对方式问卷、自卑感量表和自制的一般资料调查表,对贵州某医高专在校学生的自卑感和应对方式进行问卷调查,使用SPSS22.0统计软件包对调查数据进行t检验、Pearson相关分析和多元逐步回归分析。结果:医学生自卑感总分为(114.86±30.68),其中一年级学生(117.49±28.69)高于二年级学生(112.93±31.95),女生(119.68±30.22)高于男生(109.12±30.25),农村学生(119.52±29.56)高于城镇学生(110.30±34.45),非独生子女(115.94±29.67)高于独生子女(107.90±35.84),差异具有统计学意义(P0.05)。相关分析结果显示:自卑感与解决问题和求助应对方式呈负相关(P<0.05或P<0.01),与自责、幻想、退避和合理化应对方式呈正相关(P<0.01)。逐步回归分析结果显示:解决问题、自责、求助和退避应对方式与自卑感存在线性回归关系(P<0.01),解释自卑感变异的17.9%。结论:贵州某医高专在校学生的自卑感处于中等偏低水平,与解决问题、自责、求助、幻想、退避和合理化应对方式之间存在显著的相关关系。应及时开展心理健康教育和自卑心理干预,提高大学生心理健康水平。

关键词：自卑感应对方式相关性医学生

Theoretical Studies on the Si(001)-SiO_2 Interface Structure

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Chinese Journal of Structural Chemistry 2006年第6期25卷 647-652页

作者： ZHOU Ming-xiu YANG Chun DENG Xiao-Yan yu Wei-Fei LI Jin-Shan Key Laboratory of Computer Software Sichuan Normal University Chengdu Sichuan 610068 China China Academy of Engineering Physics Mianyang Sichuan 621000 China

Novel models （2× 1） of Si（001）-SiO2 interface structure have been established. The method of the first-principle General Gradient Approximation （GGA） is employed to structurally optimize the established theoretical models under the K-point space of periodic boundary condition. The structures after optimization have been analyzed, and the results show that the interfaces present in disordered state and both Si-O-Si and Si=O structures exist. Meanwhile, the bonding of surface structure is analyzed via the graphics of electron localization function（ELF）.

关键词： Si/SiO2 DFT interface structure

Immobilization of trophic anaerobic acetogen for semi-continuous syngas fermentation

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Chinese Journal of Chemical Engineering 2021年第1期34卷 311-316页

作者： Lijuan Zhang peng Hu Jiang Pan Huilei yu Jianhe Xu State Key Laboratory of Bioreactor Engineering Shanghai Collaborative Innovation Centre for BiomanufacturingEast China University of Science and TechnologyShanghai 200237China Shanghai GTL Biotech Co.Ltd. Shanghai 200438China

The massive consumption of fossil energy force s people to find new source s of *** fermentation has become a hot research field as its high potential in renewable energy production and sustainable *** this study,trophic anaerobic acetogen Morella thermoacetica was successfully immobilized by calcium alginate embedding *** ability of the immobilized cells on production of acetic acid through syngas fermentation was compared in both airlift and bubble column *** bubble column bioreactor was selected as the better type of *** production of acetic acid reached 32.3 g·L^(-1) in bubble column bioreactor with a space-time yield of 2.13 g·L^(-1)·d^(-1).The immobilized acetogen could be efficiently reused without significant lag period,even if exposed to air for a short time.A semi-continuous syngas fermentation was performed using immobilized cells,with an average space-time acetic acid yield of 3.20 g·L^(-1)·d^(-1).After 30 days of fermentation,no significant decrea se of the acetic acid production rate was observed.

关键词： Anaerobic Syngas Acetic acid Immobilization Bioreactors Semi-continuous fermentation

A Marine Environment Early Warning Algorithm Based on Marine Data Sampled by Multiple Underwater Gliders

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China Ocean Engineering 2019年第2期33卷 172-184页

作者： XU Zhen-zhen LI Lu yu Jian-cheng XU xiu-juan JIA Ming-fei School of Software Technology Dalian University of Technology The State Key laboratory of Robotics Shenyang Institute of AutomationCAS

This study analyzes and summarizes seven main characteristics of the marine data sampled by multiple underwater gliders. These characteristics such as the big data volume and data sparseness make it extremely difficult to do some meaningful applications like early warning of marine environment. In order to make full use of the sea trial data, this paper gives the definition of two types of marine data cube which can integrate the big marine data sampled by multiple underwater gliders along saw-tooth paths, and proposes a data fitting algorithm based on time extraction and space compression(DFTS) to construct the temperature and conductivity data cubes. This research also presents an early warning algorithm based on data cube(EWDC) to realize the early warning of a new sampled data *** results show that the proposed methods are reasonable and effective. Our work is the first study to do some realistic applications on the data sampled by multiple underwater vehicles, and it provides a research framework for processing and analyzing the big marine data oriented to the applications of underwater gliders.

关键词： big marine data early warning marine environment underwater gliders

Evaluating the effect of plain afforestation project and future spatial suitability in Beijing

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Science China Earth Sciences 2020年第10期63卷 1587-1598页

作者： Tengyun HU Xuecao LI peng GONG Wencheng yu Xiaochun HUANG Beijing Municipal Institute of City Planning and Design Beijing 100045China Department of Geological and Atmospheric Sciences Iowa State UniversityAmes 50011USA Ministry of Education Key Laboratory of Earth System Modeling Department of Earth System ScienceTsinghua UniversityBeijing 100084China Tsinghua Urban Institute Tsinghua UniversityBeijing 100084China

Taking the"One Million-Mu(666 km^2)"Plain Afforestation(PhaseⅠ)Project(Phase I afforestation)in Beijing city as an example,we monitored the growth status of planted forest using long-term remote sensing images,and evaluated the impacts of afforestation on land use change and vegetation *** found there is a large space for improvement regarding the ecological benefits of the ***,we found forest patches with decreasing greenness after the afforestation were mainly converted from farmland with high greenness and low heterogeneity in terms of the normalized difference vegetation index(NDVI).This implies that those farmland patches are inappropriate for *** to the results from PhaseⅠafforestation and the impact of urbanization on green space,we constructed a series of spatial variables and generated a suitability map for the next"New Round of One Million-Mu(666 km^2)Afforestation project"(PhaseⅡafforestation).We then modeled the spatial distribution of PhaseⅡafforestation based on the derived suitability *** study is crucial for the scientific evaluation of afforestation projects for space planning(e.g.,urban green space planning).The evaluation and modeling framework built in this study can be used to support the decision making and policy implementation of afforestation projects in China.

关键词： Urban land use Afforestation Forest growth Suitability Segmentation Forest modeling

Recent progresses on improving CO_(2)adsorption and proton production for enhancing efficiency of photocatalytic CO_(2)reduction by H_(2)O

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Green Chemical Engineering 2020年第1期1卷 33-39页

作者： peng Liu Xingcui peng yu-Long Men yun-Xiang Pan Dept.of Instrument Science and Engineering School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai200240PR China Dept.of Chemical Engineering School of Chemistry and Chemical EngineeringState Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai200240PR China

Photocatalytically reducing CO_(2)by H_(2)O into valuable carbon-containing chemicals is one of the greatest concerns for both scientific and industrial communities,due to its great potential in solving energy and environmental ***,the photocatalytic reduction efficiency is still much lower than the need of large-scale ap*** of photocatalysts in adsorbing CO_(2)and splitting H_(2)O to produce protons are crucial factors determining the photocatalytic reduction *** research efforts have been devoted to addressing the issues on CO_(2)adsorption and proton *** present review discusses the recent progresses in improving CO_(2)adsorption and proton production on photocatalysts for increasing the photocatalytic reduction *** research opportunities and challenges are also *** is hoped that the present review can stimulate more deep insights on adsorption of CO_(2)and production of proton for increasing the photocatalytic reduction efficiency。

关键词： Carbon dioxide Photocatalysis Adsorption of carbon dioxide Production of proton Water splitting

针刺颈夹脊穴联合颈椎矫正康复手法治疗神经根型颈椎病的临床效果研究

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中国伤残医学 2024年第8期32卷 83-86页

作者：于海良屈毅楠曾佳豪高思阳张铁军韩鹏苟莉晓战略支援部队兴城特勤疗养中心疗养六科辽宁葫芦岛125001

目的:观察针刺颈夹脊穴联合颈椎矫正康复手法对神经根型颈椎病患者的临床效果及其对颈椎功能的影响.方法:选择2019年8月—2021年9月在战略支援部队兴城特勤疗养中心接受康复治疗的62例神经根型颈椎病患者为研究对象,采用随机数字表法将... 详细信息

目的:观察针刺颈夹脊穴联合颈椎矫正康复手法对神经根型颈椎病患者的临床效果及其对颈椎功能的影响.方法:选择2019年8月—2021年9月在战略支援部队兴城特勤疗养中心接受康复治疗的62例神经根型颈椎病患者为研究对象,采用随机数字表法将研究对象分为对照组和观察组,每组31例.对照组采用颈椎矫正康复手法治疗,观察组采用针刺颈夹脊穴联合颈椎矫正康复手法治疗.比较2组治疗总有效率、疼痛视觉模拟(VAS)评分、颈椎功能评定量表(ASCS)评分及颈椎活动度评分.结果:观察组治疗总有效率高于对照组,差异有统计学意义(P<0.05).治疗后2周、1、3个月,2组VAS及ASCS评分均较治疗前降低,且观察组均低于对照组,差异有统计学意义(P<0.05).治疗后,观察组颈椎生理曲度C值和颈椎活动度均优于对照组,组间差异有统计学意义(P<0.05).结论:针刺颈夹脊穴联合颈椎矫正康复手法治疗神经根型颈椎病效果优于单纯应用颈椎矫正康复手法,能够改善颈椎功能及僵硬疼痛症状,且长期随访疗效稳定,利于颈椎恢复正常生理曲度,安全性高.

关键词：神经根型颈椎病颈椎矫正手法夹脊穴颈椎曲度

Passivity breakdown of 13Cr stainless steel under high chloride and CO_2 environment

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International Journal of Minerals,Metallurgy and Materials 2019年第3期26卷 329-336页

作者： Hui-xin Li Da-peng Li Lei Zhang Ya-wen Wang xiu-yun Wang Min-xu Lu Institute for Advanced Materials and Technology University of Science and Technology Beijing Safetech Research Institute (Beijing) Co. Ltd. CRRC Beijing Locomotive Co. Ltd.

Herein, the effect of high chloride ion(Cl^-) concentration on the corrosion behavior and passive film breakdown of 13Cr martensitic stainless steel under CO_2 environment was demonstrated. The Cl^- concentration was varied from 30 to 150 g/L and cyclic potentiodynamic polarization was conducted to investigate the influence of the Cl^- concentration on the corrosion potential(E_(corr)), passive breakdown potential(E_(pit)), and repassivation potential(E_(rep)). The results of the polarization curves revealed that 13Cr stainless steel is susceptible to pitting under high Cl^- concentration. The passive breakdown potential and repassivation potential decreased with the increase of Cl-concentration. The semiconducting behavior of the passive film was investigated by Mott-Schottky analysis and the point defect model(PDM). It was observed that the iron cation vacancies and oxygen vacancies were continuously generated by autocatalytic reactions and the higher Cl^- concentration resulted in higher vacancies in the passive film. Once the excess vacancies condensed at the metal/film interface, the passive film became locally detached from the metal, which led to the breakdown of the passive film.

关键词： 13Cr stainless steel electrochemical characterization pitting corrosion high chloride concentration passive film breakdown