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The Superiority of Bayes Estimators in a Multivariate Linear Model with Respect to Normal-Inverse Wishart Prior

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Acta Mathematica Sinica,English Series 2015年第6期31卷 1003-1014页

作者： Kai XU dao jiang he School of Statistics and Management Shanghai University of Finance and Economics School of Mathematics and Computer Science Anhui Normal University

In this paper, the multivariate linear model Y = XB＋e, e ～ Nm×k（0, ImΣ） is considered from the Bayes perspective. Under the normal-inverse Wishart prior for （BΣ）, the Bayes estimators are derived. The superiority of the Bayes estimators of B and Σ over the least squares estimators under the criteria of Bayes mean squared error （BMSE） and Bayes mean squared error matrix （BMSEM） is shown. In addition, the Pitman Closeness （PC） criterion is also included to investigate the superiority of the Bayes estimator of B.

关键词： Normal-inverse Wishart distribution matrix t distribution Bayes estimator least' squaresestimator Pitman closeness criterion BMSE and BMSEM criteria

有缺失数据的条件独立正态母体中参数的最优同变估计

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数学学报（中文版） 2016年第6期59卷 783-794页

作者：许凯何道江上海财经大学统计与管理学院上海200433 安徽师范大学数学计算机科学学院芜湖241000

在缺失数据机制是可忽略的假设下,导出了有单调缺失数据的条件独立正态模型中协方差阵和精度阵的Cholesky分解的最大似然估计和无偏估计.通过引入一类特殊的变换群并在更广义的损失下,获得了其最优同变估计.这表明最大似然估计和无偏估... 详细信息

在缺失数据机制是可忽略的假设下,导出了有单调缺失数据的条件独立正态模型中协方差阵和精度阵的Cholesky分解的最大似然估计和无偏估计.通过引入一类特殊的变换群并在更广义的损失下,获得了其最优同变估计.这表明最大似然估计和无偏估计是非容许的.最后,通过数值模拟验证了相关结果的有效性.

关键词： Cholesky分解同变估计不变Haar测度

High Speed Sintering:Assessing the Influence of Energy Input on Microstructure and Mechanical Properties of Polyether Block Amide(PEBA)Parts

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Chinese Journal of Polymer Science 2024年第5期42卷 675-682,I0004,I0010页

作者： jiang-Tao Sun Zhi-Yong Fan Yi-Wei Mao Wei Li Wei Zhu dao-Sheng Cai Qing-Song Wei State Key Laboratory of Materials Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhan430074China State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430074China National Engineering Research Centre for High Efficiency Grinding Hunan UniversityChangsha410082China Wuhan EasyMFG Technology CO. LTDWuhan430074China

High speed sintering,a new powder-bed fusion additive manufacturing technology,utilizes infrared lights(IR)to intensely heat and melt polymer *** presence of defects such as porosity,which is associated with particle coalescence,is highly dependdent on the level of energy *** study investigate the influcence of energy input on porosity and its subsequent effects on the mechanical properties and microstructures of PEBA *** parts were manufactured with a variety of lamp powers,resulting in a range of energy input levels spanning from low to ***,they underwent testing using Archimedes’method,followed by tensile *** porosity,mechanical characteristics,and energy input exhibit a strong correlation;inadequate energy input was the primary cause of pore *** the reduced IR light power resulted in the following outcomes:porosity,ultimate tensile strength,and elongation of 1.37%,7.6 MPa,and 194.2%,*** the energy input was further increased,the porosity was reduced to as low as 0.05%and the ultimate tensile strength and elongation were increased to their peak values of 233.8%and 9.1 MPa,respectively.

关键词： High speed sintering Additive manufacturing Energy input Powder bed fusion PEBA

Recent progress and strategies of cathodes toward polysulfides shuttle restriction for lithium-sulfur batteries

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Rare Metals 2024年第9期43卷 4132-4161页

作者： Xing-You Rao Shuang-Fei Xiang Jian Zhou Zhen Zhang Xiang-Yu Xu Yuan-Yuan Xu Xin-Chi Zhou Zheng-dao Pan Su-Chong Tan Shi-Xing Dong Zhou-Lu Wang Yu-Tong Wu Yun-Lei Zhou Xiang Liu Yi Zhang Shan jiang School of Energy Sciences and Engineering Nanjing Tech UniversityNanjing 211816China School of Materials Science and Engineering and Institute of Smart Fiber Materials Zhejiang Sci-Tech UniversityHangzhou 310018China jiangSu Sailboat Petrochemical Co. LtdLianyungang 222000China Hangzhou Institute of Technology Xidian UniversityHangzhou 311200China

Lithium-sulfur batteries(LSBs)have already developed into one of the most promising new-generation high-energy density electrochemical energy storage systems with outstanding features including high-energy density,low cost,and environmental ***,the development and commercialization path of LSBs still presents significant limitations and challenges,particularly the notorious shuttle effect triggered by soluble longchain lithium polysulfides(LiPSs),which inevitably leads to low utilization of cathode active sulfur and high battery capacity degradation,short cycle life,*** research efforts have been conducted to develop various sulfur host materials capable of effectively restricting the shuttle *** review firstly introduces the fundamental electrochemical aspects of LSBs,followed by a comprehensive analysis of the mechanism underlying the shuttle effect in Li–S batteries and its profound influence on various battery components as well as the overall battery ***,recent advances and strategies are systematically reviewed,including physical confinement,chemisorption,and catalytic conversion of sulfur hosts for restricting LiPSs shuttle *** interplay mechanisms of sulfur hosts and LiPSs are discussed in detail and the structural advantages of different host materials are ***,key insights for the rational design of advanced host materials for LSBs are provided,and the upcoming challenges and the prospects for sulfur host materials in lithium-sulfur batteries are also explored.

关键词： Lithium-sulfur batteries Polysulfides Shuttle effect Host

铝土岩系和煤系地层中沉积黏土型锂矿床:研究现状与展望

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矿物岩石地球化学通报 2024年第1期43卷 90-101页

作者：张七道蒋少涌王微葛文中国地质大学(武汉)地质过程与矿产资源国家重点实验室资源学院紧缺战略矿产资源协同创新中心武汉430074 中国地质调查局昆明自然资源综合调查中心昆明650100 中国地质大学(武汉)材料与化学学院武汉430074

沉积岩型锂矿是自然界中最主要的锂矿床之一,我国铝土岩系和煤系地层中沉积黏土型锂矿主要分布在扬子地块西南部和华北地块,该类型锂矿分布广、储量大,对其进行研究对破解我国未来锂资源困局具有重要意义。本文总结了我国铝土岩系和煤... 详细信息

沉积岩型锂矿是自然界中最主要的锂矿床之一,我国铝土岩系和煤系地层中沉积黏土型锂矿主要分布在扬子地块西南部和华北地块,该类型锂矿分布广、储量大,对其进行研究对破解我国未来锂资源困局具有重要意义。本文总结了我国铝土岩系和煤系地层中黏土型锂矿的分布状况,锂的赋存状态、来源,以及开发利用现状等方面的研究进展。锂的富集过程主要与风化-沉积作用及火山岩浆活动有关,锂主要来源于火山凝灰岩、早期形成的岩浆岩、黏土岩等富锂基底岩石。锂以锂绿泥石独立矿物或者类质同象/吸附在黏土矿物、三水铝石和勃姆石中。锂的提取流程与锂的赋存状态密切相关。随着实验及工业提锂技术的发展,该类型锂资源具有广阔的前景。

关键词：沉积黏土型锂矿铝土岩系煤系地层锂赋存状态物质来源开发利用潜力

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明清徽州慈善文化的成因、特质和历史贡献

蚌埠学院学报 2024年第3期13卷 95-99页

作者：蒋道霞安徽师范大学历史学院安徽芜湖241002

崇儒重教的文化传统、同宗抱团的宗族思想、徽商对故土的认同、商业经济的风险是明清徽州慈善文化的成因。明清徽州慈善文化具有商贾反哺乡村、商业反哺教育、宗族内部互济、践行儒家思想的特质,在倡导扶贫济困的善举、维护宗族的整体... 详细信息

崇儒重教的文化传统、同宗抱团的宗族思想、徽商对故土的认同、商业经济的风险是明清徽州慈善文化的成因。明清徽州慈善文化具有商贾反哺乡村、商业反哺教育、宗族内部互济、践行儒家思想的特质,在倡导扶贫济困的善举、维护宗族的整体利益、促进徽州乡村社会的善治、助力徽州乡村社会的繁荣方面作出了历史贡献。传承明清徽州慈善文化,有利于为当前我国乡村振兴战略的实施提供借鉴。

关键词：徽州地区慈善文化成因特质贡献

混合所有制改革与民营经济高质量发展——基于企业ESG表现视角的研究

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经济问题 2024年第3期 16-22页

作者：邵剑兵姜道平辽宁大学经济学部商学院辽宁沈阳110036

以2013—2021年沪深A股上市公司为研究样本,实证检验了国有资本参股对民营企业ESG表现的影响。研究发现,国有资本参股程度越高,民营企业ESG的表现越好。机制检验表明,国有资本参股通过提高环保补助、强化社会责任信息披露质量和降低第... 详细信息

以2013—2021年沪深A股上市公司为研究样本,实证检验了国有资本参股对民营企业ESG表现的影响。研究发现,国有资本参股程度越高,民营企业ESG的表现越好。机制检验表明,国有资本参股通过提高环保补助、强化社会责任信息披露质量和降低第二类代理成本提高民营企业的ESG表现。此外,国家股参股和国有股权参与度高的企业中,国有资本参股对民营企业ESG表现的促进作用更为显著。分项检验发现,国有资本参股主要通过提高社会和治理维度来提高民营企业的ESG表现,而国有资本参股对环境表现的提高作用存在环境治理和压力的差异性。

关键词：逆向混改环境、社会和治理环保补助社会责任信息披露代理成本

The complete mitochondrial genomes of five blind scolopendromorph centipedes and phylogenetic within Scolopendromorpha(Chilopoda)

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Zoological Systematics 2024年第4期 299-308页

作者： Tianyun Chen Chao jiang State Key Laboratory for Quality Ensurance and Sustainable Use of dao-di herbs National Resource Center for Chinese Materia MedicaChina Academy of Chinese Medical Sciences

Mitochondrial genomes of five Tykhepoda scolopendromorphs(Cryptopidae,Scolopocryptopidae and Plutoniumidae) are sequenced and analyzed using methods of comparative genomics to provide more information on the phylogeny of *** locations of 22 t RNAs, 13 PCGs, and 2 rRNAs are annotated. The heavy chain of mitochondrial genomes are 14,841–15,619 bp in length. A+T % vary from 64.79% to 77.40%,and mitochondrial genomes are CG and AT skewed. The phylogenetic reconstructions showed the blind clade, recently named Tykhepoda, is monophyletic with high support values(BS = 100%and PP = 1).

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基于仿真分析的小模数齿轮传动及降噪设计

环境技术 2024年第3期42卷 125-131页

作者：罗道江西南电子技术研究所成都610036

针对影响雷达传动转台噪声形成的主要影响因数,运用动力学分析结合振动噪声仿真等现代传动设计技术,对机械扫描雷达小模数齿轮传动系统结构模型进行优化设计,解决了齿轮传动系统降噪声设计主要依靠经验数据的粗略设计模式而导致降噪效... 详细信息

针对影响雷达传动转台噪声形成的主要影响因数,运用动力学分析结合振动噪声仿真等现代传动设计技术,对机械扫描雷达小模数齿轮传动系统结构模型进行优化设计,解决了齿轮传动系统降噪声设计主要依靠经验数据的粗略设计模式而导致降噪效果不一的问题,为齿轮传动系统提供了较为精准的降噪声优化设计方法,运用齿轮传动系统降噪设计模式对某雷达传动系统降噪设计达到良好的降噪设计效果。

关键词：系统结构模型动力学仿真噪声仿真