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The Consistency of LSE Estimators in Partial Linear Regression Models under Mixing Random Errors

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Acta Mathematica Sinica,English Series 2024年第5期40卷 1244-1272页

作者： yun bao YAO Yu Tan LÜ Chao LU Wei WANG Xue Jun WANG School of Mathematical Sciences Anhui UniversityHefei 230601P.R.China School of Big Data and Artificial Intelligence Chizhou UniversityChizhou 247000P.R.China School of Big Data and Statistics Anhui UniversityHefei 230601P.R.China

In this paper,we consider the partial linear regression model y_(i)=x_(i)β^(*)+g(ti)+ε_(i),i=1,2,...,n,where(x_(i),ti)are known fixed design points,g(·)is an unknown function,andβ^(*)is an unknown parameter to be estimated,random errorsε_(i)are(α,β)-mix_(i)ng random *** p-th(p>1)mean consistency,strong consistency and complete consistency for least squares estimators ofβ^(*)and g(·)are investigated under some mild *** addition,a numerical simulation is carried out to study the finite sample performance of the theoretical ***,a real data analysis is provided to further verify the effect of the model.

关键词： (α,β)-mixing random variables partial linear regression model least squares estimator consistency

Elimination of cracks in stainless steel casings via 3D printed sand molds with an internal topology structure

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China Foundry 2024年第4期21卷 319-326页

作者： Jun-hang Xu bao-zhi Li Zhao-wei Song yun-bao Gao Jing-ming Li Yu Wang Qiu-lin Wen Heng Cao Zeng-rui Wang National Key Laboratory of Advanced Casting Technologies Shenyang 110022China Shenyang Research Institute of Foundry Co. Ltd.CAMShenyang 110022China

The important supporting component in a gas turbine is the casing,which has the characteristics of large size,complex structure,and thin *** the context of existing 3DP sand casting processes,casting crack defects are prone to *** leads to an increase in the scrap rate of casings,causing significant resource ***,the presence of cracks poses a significant safety hazard after the casings are put into *** generation of different types of crack defects in stainless steel casings is closely related to casting stress and the high-temperature concession of the sand ***,the types and causes of cracks in stainless steel casing products,based on their structural characteristics,were systematically *** sand molds with different internal topology designs were printed using the 3DP technology to investigate the impact of sand mold structures on high-temperature *** optimal sand mold structure was used to cast casings,and the crack suppression effect was verified by analyzing its eddy current testing *** experimental results indicate that the skeleton structure has an excellent effect on suppressing cracks in the *** research holds important theoretical and engineering significance in improving the quality of casing castings and reducing production costs.

关键词： gas turbine casing crack defects 3D printed sand mold topological structure high-temperature concession

Artemordins A-S, Cadinane-Type Sesquiterpenoid Dimers from Artemisia ordosica and Their Antihepatoma Activities

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Chinese Journal of Chemistry 2024年第13期42卷 1493-1508页

作者： Yuan Wang Tian-Ze Li yun-bao Ma Chang-An Geng Yong-Cui Wang Ji-Jun Chen State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China University of Chinese Academy of Sciences Beijing 100049China

Nineteen new cadinane-involving sesquiterpenoid dimers,artemordins A-S(1-—19),together with 13 known SDs(20-32)were isolated from Artemisia *** structures and absolute configurations were established by comprehensive spectral analyses,X-ray single crystal diffraction,theoretical ECD,and NMR ***,artemordins A-F(1—6)were the first examples of two cadinane units constructed by unprecedented C-3−C-15′or C-3−C-13′single bond with an oxido-rearranged 6/5/6/6 fused ring system;artemordins G-K(7-11)were biogenetically connected by[4+2]cycloaddition reaction and artemordins G-J(7-10)possessed a novel 5/6/6/6/6/6/5-heptacyclic fused ring *** L-S(12-19)were formed by esterification,which involved three different types of *** assay suggested that the most active compounds,artemordins B and H(2 and 8),exhibited inhibitory activities on three hepatoma cell lines with IC50 values of 26.9 and 25.1μmol/L(HepG2),29.5 and 18.3μmol/L(Huh7),19.7 and 15.7μmol/L(SK-Hep-1).

关键词： Artemisia ordosica Artemordins A-s Cadinane-type sesquiterpenoid dimers Antihepatoma activities Terpenoids Natural products Cytotoxicity

Long Non-coding RNA PCED1B Antisense RNA 1 Promotes Cell Proliferation and Invasion in Hepatocellular Carcinoma by Regulating the MicroRNA-34a/CD44 Axis

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Current Medical Science 2024年第3期44卷 503-511页

作者： Jian-gang BI Qi LI Yu-sheng GUO Li-ping LIU Shi-yun bao Ping XU Department of Hepatobiliary and Pancreatic Surgery Shenzhen People's HospitalThe Second Clinical Medical CollegeJinan UniversityThe First Affiliated HospitalSouthern University of Science and TechnologyShenzhen 518020China Department of Endocrinology Shenzhen People's HospitalThe Second Clinical Medical CollegeJinan UniversityThe First Affiliated HospitalSouthern University of Science and TechnologyShenzhen 518020China

Objective This study aimed to examine the role of long non-coding RNA PCED1B antisense RNA 1(PCED1B-AS1)in the development of hepatocellular carcinoma(HCC).Methods A total of 62 pairs of HCC tissues and adjacent non-tumor tissues were obtained from 62 HCC *** interactions of PCED1B-AS1 and microRNA-34a(miR-34a)were detected by dual luciferase activity assay and RNA pull-down *** RNA expression levels of PCED1B-AS1,miR-34a and CD44 were detected by RT-qPCR,and the protein expression level of CD44 was determined by Western *** cell proliferation was detected by cell proliferation assay,and the cell invasion and migration by transwell invasion *** HCC tumor growth after PCED1B-AS1 was downregulated was determined by in vivo animal *** PCED1B-AS1 was highly expressed in HCC tissues,which was associated with poor survival of HCC ***,PCED1B-AS1 interacted with miR-34a in HCC cells,but they did not regulate the expression of each ***,PCED1B-AS1 increased the expression level of CD44,which was targeted by *** cell proliferation and invasion assay revealed that miR-34a inhibited the proliferation and invasion of HCC in vitro,while CD44 exhibited the opposite ***,PCED1B-AS1 suppressed the role of ***,the knockdown of PCED1B-AS1 repressed the HCC tumor growth in nude mice in *** PCED1B-AS1 may play an oncogenic role by regulating the miR-34a/CD44 axis in HCC.

关键词： long non-coding RNA PCED1B antisense RNA 1(PCED1B-AS1) hepatocellular carcinoma microRNA-34a(miR-34a) CD44 proliferation invasion

Geological reservoir and resource potential(10^(13)m^(3))of gas hydrates in the South China Sea

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China Geology 2024年第3期7卷 422-444页

作者： Pi-bo Su Wei Wei yun-bao Sun Yao-yao Lü Huai Cheng Wei-feng Han Wei Zhang Jin-qiang Liang National Engineering Research Center for Gas Hydrate Exploration and Development Guangzhou 511458China Sanya Institute of South China Sea Geology Guangzhou Marine Geological SurveySanya 572025China Central Laboratory of Geological Sciences Research Institute of Petroleum Exploration and DevelopmentLangfang 065007China Qingdao Institute of Marine Geology Qingdao 266237China Laboratory for Marine Mineral Resources Qingdao Marine Science and Technology CenterQingdao 266237China

A detailed understanding of the distribution and potential of natural gas hydrate(NGHs)resources is crucial to fostering the industrialization of those resources in the South China Sea,where NGHs are *** this study,this study analyzed the applicability of resource evaluation methods,including the volumetric,genesis,and analogy methods,and estimated NGHs resource potential in the South China Sea by using scientific resource evaluation methods based on the factors controlling the geological accumulation and the reservoir characteristics of ***,this study compared the evaluation results of NGHs resource evaluations in representative worldwise sea areas via rational *** results of this study are as follows:(1)The gas hydrate accumulation in the South China Sea is characterized by multiple sources of gas supply,multi-channel migration,and extensive accumulation,which are significantly different from those of oil and gas and other unconventional resources.(2)The evaluation of gas hydrate resources in the South China Sea is a highly targeted,stratified,and multidisciplinary evaluation of geological resources under the framework of a multi-type gas hydrate resource evaluation system and focuses on the comprehensive utilization of multi-source heterogeneous data.(3)Global NGHs resources is n×10^(15)m^(3),while the NGHs resources in the South China Sea are estimated to be 10^(13)m^(3),which is comparable to the abundance of typical marine NGHs deposits in other parts of the *** the South China Sea,the NGHs resources have a broad prospect and provide a substantial resource base for production tests and industrialization of NGHs.

关键词： Reservoir characteristics Natural gas hydrates Gas migration Resource potential Resource evaluation methods Hierarchical evaluation system Volumetric method South China Sea Clean energy exploration engineering

考虑多类型时间依赖资源约束的敏捷卫星调度优化

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控制理论与应用 2024年第6期41卷 1038-1046页

作者：李君邢立宁彭观胜徐运保湖南工程学院管理学院湖南长沙410073 西安电子科技大学电子工程学院陕西西安710071 中国人民解放军军事科学院国防科技创新研究院北京100000

随着现代空间科技的迅猛发展,光学遥感图像数据的应用需求越来越广泛,大力推动了光学对地观测卫星的发展.然而,由于高昂的发射成本的约束,对地观测卫星的资源是有限的,远远无法满足各类数据需求.因此,提高对地观测卫星的使用效率,提高... 详细信息

随着现代空间科技的迅猛发展,光学遥感图像数据的应用需求越来越广泛,大力推动了光学对地观测卫星的发展.然而,由于高昂的发射成本的约束,对地观测卫星的资源是有限的,远远无法满足各类数据需求.因此,提高对地观测卫星的使用效率,提高其任务执行率,具有非常重要的应用价值.本文聚焦于敏捷对地观测卫星的任务调度问题,即在给定的调度周期内,对有限的卫星资源制定合理的任务调度方案,在满足一定星上资源约束下,最大化观测任务收益.该问题难点在于星上的资源是非常有限的,例如存储图像数据的固存资源、用于采集数据和卫星姿态切换的能量资源及执行任务活动耗费的时间资源.需要注意的是,能量消耗量和时间消耗量依赖于任务的执行时间,这是敏捷卫星相对传统的非敏捷卫星独有的特性.不同任务场景对不同类型资源的需求不同,多种资源约束互相耦合,资源约束具有时间依赖特性,这些难点无疑极大地增加了卫星调度的求解难度.为高效地求解该问题,本文构建了多类型时间依赖资源约束的敏捷卫星调度整数规划模型,并针对问题特性提出了一种基于自适应选择因子的迭代局部搜索启发式算法.自适应选择因子综合考虑了目标收益、资源消耗量、资源约束的松弛量,采用动态变化的资源重要度,能快速自适应地根据当前场景下各种类型的资源数据使用量来确定最佳局部搜索方向,从而在有限时间内找到高质量的解.实验结果证明,本文所提出的算法在多种情况下相比当前最好算法求解效果显著更优.此外,算法独有的自适应选择因子相比传统的选择因子的求解质量更高,这是因为所设计的自适应选择因子兼顾了目标收益和资源消耗量之间权衡关系的同时,采用动态变化的资源重要度准确捕捉了资源需求的迫切程度.

关键词：卫星调度迭代局部搜索动态规划时间依赖性数据验证

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热−力耦合作用下垃圾土体积变形特性和模型研究

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岩土力学 2024年第1期45卷 49-58,67页

作者：李玉萍陈嘉瑞施建勇樊宝云河海大学岩土力学与堤坝工程教育部重点实验室江苏南京210098 河海大学岩土工程研究所江苏南京210098

城市生活垃圾填埋场因有机质降解产热导致其内部温度长期高于环境温度,引发工程运维问题。垃圾土温控三轴试验结果发现,温度变化引起的垃圾土体积应变与应力水平有关,且弹性体积应变占比较大,影响以塑性体积应变为硬化参数的弹塑性本构... 详细信息

城市生活垃圾填埋场因有机质降解产热导致其内部温度长期高于环境温度,引发工程运维问题。垃圾土温控三轴试验结果发现,温度变化引起的垃圾土体积应变与应力水平有关,且弹性体积应变占比较大,影响以塑性体积应变为硬化参数的弹塑性本构模型研究。在前期试验基础上,采用GDS温控应力路径三轴仪,研究了排水条件下温度对垃圾土中黏土体积变形特性和压缩特性的影响,并与相同条件下垃圾土体积变形特性进行比较,揭示了温度变化对垃圾土体积变形特性的影响机制。基于垃圾土温控三轴试验结果,推导了垃圾土热弹塑性压缩指数λT和热弹性压缩指数κT的确定方法;采用等效应力原则,假设温度变化引起的弹塑性体积应变等于某一等效应力增量引起的弹塑性体积应变,建立了垃圾土在热−力耦合作用下的体变计算模型,并对模型进行了验证分析。研究结果表明,孔隙比是影响垃圾土温度体积应变的主要因素;垃圾土的λT和κT随初始固结应力的增加而减小,比黏土高一个数量级;选取常温下相应固结应力水平的回弹指数κ和压缩指数λ比例值(κ/λ)能够较好地模拟热−力耦合作用下垃圾土的体积变形特性。

关键词：垃圾土热-力耦合作用体积变形弹性体积应变塑性体积应变

考虑温湿度作用的粒料基层沥青路面结构非线性力学行为

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长安大学学报（自然科学版） 2024年第1期44卷 24-35页

作者：黄优潘宇肖滨刘朝晖张允宝长沙理工大学道路灾变防治及交通安全教育部工程研究中心湖南长沙410114 长沙理工大学交通运输工程学院湖南长沙410114 湖南省交通运输厅交通建设造价管理站湖南长沙410011

为了研究温湿度作用下道路结构非线性力学行为,基于长期性能观测构建粒料基层沥青路面的温湿度组合,建立综合考虑应力和湿度影响的粒料非线性回弹模量模型,考察2个沥青层厚度和2个荷载水平,利用有限元开展沥青路面粒料层和土基非线性结... 详细信息

为了研究温湿度作用下道路结构非线性力学行为,基于长期性能观测构建粒料基层沥青路面的温湿度组合,建立综合考虑应力和湿度影响的粒料非线性回弹模量模型,考察2个沥青层厚度和2个荷载水平,利用有限元开展沥青路面粒料层和土基非线性结构力学行为分析,基于Miner’s损伤法则,计算基于沥青层底拉应变和土基顶部压应变的疲劳寿命。研究结果表明:采用考虑湿度调整的Uzan三参数模型能够较好地表征在役沥青路面粒料层和土基的非线性力学行为;非线性路面结构分析与现有线弹性路面结构计算相比,沥青层底拉应变和土基顶部压应变大小及其对温湿度变化的敏感程度均存在显著差异,结构寿命也相差较大,温湿度对道路结构力学行为的影响不容忽视;增加荷载和减小沥青面层厚度均会增加沥青路面结构响应、降低使用寿命,但是二者的影响机理不同;粒料应力硬化特性能在一定程度上缓解高应力水平下的沥青层底受拉。

关键词：道路工程沥青路面有限元粒料材料动态回弹模量路面结构力学行为非线性

涉中国-东盟数字贸易法治人才培养的价值和策略

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呼伦贝尔学院学报 2024年第1期32卷 86-90页

作者：包运成贵州师范大学贵州贵阳550025

涉中国—东盟数字贸易法治人才培养,是适应中国—东盟数字贸易迅速发展的需要,是落实中国—东盟现有数字贸易规则的需要,也是适应我国加入DEPA和CPTPP等新规则的需要。强化涉中国—东盟数字贸易法治人才培养是一项复杂的系统工程,需要... 详细信息

涉中国—东盟数字贸易法治人才培养,是适应中国—东盟数字贸易迅速发展的需要,是落实中国—东盟现有数字贸易规则的需要,也是适应我国加入DEPA和CPTPP等新规则的需要。强化涉中国—东盟数字贸易法治人才培养是一项复杂的系统工程,需要各个方面共同努力,当前可以几个方面着力:强化涉中国—东盟数字贸易法治人才培养顶层设计和统筹规划;加强涉中国—东盟数字贸易法治人才复合能力专项培养;强化涉中国—东盟数字贸易法治人才实践能力培养。

关键词：中国—东盟数字贸易法治人才培养