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Measuring Environmental Performance of Provincial Thermal Power Plants in China:A Malmquist DEA Approach with Fixed-Sum Undesirable Outputs

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Journal of Systems Science & Complexity 2022年第4期35卷 1201-1224页

作者： HOU Wenhui ZHENG Yunwen liANG liang li yongjun School of Management University of Science and Technology of ChinaHefei230026China

With the development of China’s economy,environmental pollution has become cumulatively serious.The primary source of environmental pollution is thermal power generation,which has attracted the attention of governments and academia in recent years.To effectively reduce environmental pollution,research should study how to constrain the undesirable output of thermal power plants,that is,to limit the total undesirable output of the plants to a certain fixed sum.However,few studies have suggested that these undesirable outputs should be fixed-sum outputs.Moreover,no previous research publication about thermal power plants has analyzed their environmental performance changes.To address these gaps,a novel Malmquist-DEA approach is proposed for evaluate the environmental performance of thermal power plants in this paper.This approach generalizes the equilibrium efficient frontier DEA model with fixed-sum undesirable outputs and incorporates the model into the Malmquist productivity index(MPI).The authors apply this approach to the analysis of provincial thermal power plant environmental performance in China and analyze such plants’trends based on panel data from2011 to 2014.The empirical research shows that the environmental performance of regional thermal power plants was positively affected by efficiency change and negatively affected by technical change.Finally,the authors provide policy suggestions based on our findings.

关键词： Data envelopment analysis environmental performance fixed-sum undesirable outputs Malmquist productivity index thermal power plants

Stock Efficiency Evaluation Based on Multiple Risk Measures:A DEA-like Envelopment Approach

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Journal of Systems Science & Complexity 2022年第4期35卷 1480-1499页

作者： li Jun GAO Hengxuan li yongjun JIN Xi liANG liang School of Management University of Science and Technology of ChinaHefei230026China School of Management Hefei University of TechnologyHefei230009China

This paper proposes a new approach for stock efficiency evaluation based on multiple risk measures. A derived programming model with quadratic constraints is developed based on the envelopment form of data envelopment analysis(DEA). The derived model serves as an input-oriented DEA model by minimizing inputs such as multiple risk measures. In addition, the Russell input measure is introduced and the corresponding efficiency results are evaluated. The findings show that stock efficiency evaluation under the new framework is also effective. The efficiency values indicate that the portfolio frontier under the new framework is more externally enveloped than the DEA efficient surface under the standard DEA framework.

关键词： Data envelopment analysis(DEA) multiple risk measures portfolio selection stock efficiency evaluation

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思维方式传统与当代中国法治模式的路径选择

法学家 2024年第1期 1-14,191页

作者：李拥军吉林大学法学院

文化自信来自于文化的主体性。思维方式是一个民族的文化的重要组成部分,具有极强的稳定性。思维方式传统决定或影响着一个国家法治模式的选择和法治道路的走向。中国传统思维方式的核心特征在于“合”,而西方传统思维方式的核心特征则... 详细信息

文化自信来自于文化的主体性。思维方式是一个民族的文化的重要组成部分,具有极强的稳定性。思维方式传统决定或影响着一个国家法治模式的选择和法治道路的走向。中国传统思维方式的核心特征在于“合”,而西方传统思维方式的核心特征则在于“分”。西方的思维方式传统成就了其严密封闭的法律体系和司法适用;中国的思维方式传统孕育了其开放性、实用性的法律结构和司法适用。当今世界,中西方思维方式开始走到一起,西方法学对形式化的法律体系和司法模式进行了反思。当下中国在从传统迈向现代的过程中,确实需要思维方式转换,但这种转换绝不是中西方本源性思维方式的简单置换,而是要实现思维方式融合后的升华。在综合性思维方式下,中国的法治模式应该具有自己的面相。

关键词：思维方式法治模式主客二元关联性思维文化自信

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论居住权在民法典中的体系定位

比较法研究 2024年第1期 63-75页

作者：李永军中国政法大学

居住权在我国民法典上属于一种明文规定的用益物权,但从《民法典》第366条之规定看,没有认真区分物权与债权,甚至不能涵盖所有的居住权设立方式——居住权不仅可以通过合同设立,也可以通过遗嘱和法院裁判设立。居住权不仅可以是他物权,... 详细信息

居住权在我国民法典上属于一种明文规定的用益物权,但从《民法典》第366条之规定看,没有认真区分物权与债权,甚至不能涵盖所有的居住权设立方式——居住权不仅可以通过合同设立,也可以通过遗嘱和法院裁判设立。居住权不仅可以是他物权,也可以以自物权的形式出现——住宅所有权人的居住权也可以设立。尽管我国民法典第368条规定居住权属于登记物权,但在我国司法实践中也存在非登记的物权性居住权。居住权既可以在整个住宅上设立,也可以在住宅的一部分上设立,但是,该部分必须具有居住的功能。居住权可以为单个自然人设立,也可以设立共有居住权。通过遗嘱设立居住权的,无论是遗赠还是其他,都属于新权利的设立而非简单的继承,在遗嘱生效的时候仅仅产生债权性请求权而不发生直接的取得居住权。因此,我国民法典第230条不应适用于包括遗嘱设立居住权。居住权制度的目的在于首先满足生活居住的需要,不应该把商业化作为民法典之居住权的首要目的,当然也不能在现代社会中与商业化完全脱钩。另外,居住权作为需要登记生效的他物权在与其他物权登记的关系上,应采取登记优先则效力优先的原则,例如,居住权与抵押权的关系上,孰先登记孰之效力优先。

关键词：居住权住宅农村宅基地他物权遗嘱用益物权

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效力瑕疵合同返还不能时折价补偿的计算标准

南京社会科学 2024年第3期 76-88页

作者：李永军李昶中国政法大学民商经济法学院北京100088

《民法典》第157条规定效力瑕疵合同返还不能时应折价补偿,但并未对折价补偿的计算标准作具体规定。对此主要有客观价额说与主观价额说两种观点。《九民纪要》坚持以双方约定价款作为折价补偿的计算标准,并对标的物的涨跌以平均分摊为原... 详细信息

《民法典》第157条规定效力瑕疵合同返还不能时应折价补偿,但并未对折价补偿的计算标准作具体规定。对此主要有客观价额说与主观价额说两种观点。《九民纪要》坚持以双方约定价款作为折价补偿的计算标准,并对标的物的涨跌以平均分摊为原则,综合考虑多种要素予以适当倾斜。《九民纪要》中的这一主观价额标准以及相关规定存在一定问题。最高院在《合同编通则解释》中对《九民纪要》作了部分修正,采用了以客观价额标准为主的计算标准,但在如何确定评估客观价额的时间以及合理方式等问题上仍有待进一步完善和补充。折价补偿原则上应采客观价额标准,但实施中也存在一些例外。在因转售标的物等情况产生增值或贬值时,相应的增值或贬值部分应在折价补偿时全部归于得利人。标的物客观价额的评估时间点应为财产移转时,对其估价方式的选择应遵循比例原则。

关键词：折价补偿效力瑕疵合同返还清算不当得利风险负担

Allocating Fixed Costs with Considering the Return to Scale: A DEA Approach

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Journal of Systems Science & Complexity 2016年第5期29卷 1320-1341页

作者： DAI Qianzhi li yongjun liANG liang School of Management University of Science and Technology of China Institute of Policy and Management Chinese Academy of Sciences

When the allocated fixed cost is treated as the complement of other costs, conventional data envelopment analysis(DEA) researches have ignored the effect of the return to scale(RTS) in fixed cost allocation problems. This paper first demonstrates why the RTS should be considered in fixed cost allocation problems. Then treating the fixed cost as a complementary input, the authors investigate the relationship between the allocated cost and the variable return to scale(VRS) efficiency based on the super BCC DEA model. However, the infeasibility problem may exist in this situation.To deal with it, the authors propose an algorithm. The authors find that the super BCC efficiency is a monotone non-increasing function of the allocated cost. Based on the relationship, the authors finally propose a fixed cost allocation approach in terms of principles as:(i) The fixed cost proportion allocated to inelastic DMUs should be consistent with their consumed cost proportion, and(ii) the same efficiency satisfaction degree to the rest DMUs. The optimal allocation scheme is unique. A numerical example and a real example of allocating fixed costs among 13 subsidiaries are employed to illustrate the proposed approach.

关键词：数据包封分析(DEA ) 固定成本分配 infeasibility 回到规模(RTS )

The formation mechanism of accretionary wedge at Karamay in West Junggar,NW China

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Science China Earth Sciences 2017年第3期60卷 546-556页

作者： YANG GaoXue li yongjun TONG lili li GanYu Earth Science and Resources College Chang'an UniversityXi'an 710054China

Accretionary wedge is the typical product of subduction-zone processes at shallow depths.Determining the location,composition and mechanism of accretionary wedge has important implications for understanding the tectonism of plate subduction.The Central Asian Orogenic Belt(CAOB) is one of the world's largest accretionary orogenic belts,and records the bulk evolution of Paleo-Asian Ocean from opening to closure,with multi-stages and multi-types of crust-mantle interaction in the Paleozoic.West Junggar(western part of Junggar Basin),located in the core area of CAOB,is characterized by a multiple intra-oceanic subduction system during the Paleozoic.In its eastern part crop out Devonian-Carboniferous marine sedimentary rocks,Darbut and Karamay ophiolitic melanges,alkali oceanic island basalts,island arc volcanic rocks and thrusted nappe structure.Such lithotectonic associations indicate the occurrence of accretionary wedge at Karamay.In order to decipher its formation mechanism,this paper presents a synthesis of petrography,structural geology and geochemistry of volcanic rocks.In combination with oceanic subduction channel processes,itis suggested that the accretionary wedge is acomposite melange with multiple stages of formation.The application of oceanic subduction channel model to the Karamay accretionary wedge provides new insights into the accretion and orogenesis of CAOB.

关键词：海洋的外壳 Subduction 地区地球化学海洋的岛暗岩 Ophiolitic m

Application of Graphdiyne and Its Analogues in Photocatalysis and Photoelectrochemistry

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Chemical Research in Chinese Universities 2021年第6期37卷 1195-1212页

作者： HU Guilin HE Jingyi li yongjun Beijing National Laboratory for Molecular Sciences(BNLMS) CAS Key Laboratory of Organic SolidsInstitute of ChemistryCAS Research/Education Center for Excellence in Molecular SciencesChinese Academy of SciencesBeijing100190P.R.China University of Chinese Academy of Sciences Beijing100049P.R.China

Graphdiyne(GDY),a new carbon allotrope composed of sp-sp^(2) carbon atoms,has attracted increased attention in recent years.It has a direct band gap of 0.46-1.22 eV,high charge carrier mobility and lower work function compared to most of the typical semiconductors,which ensure successful hybridization with other semiconductors(e.g.,TiO_(2),g-C_(3)N_(4)).This review aims at discussing recent achievements of GDY and its analogues applied in photocatalytic and photoelectrochemical(PEC)reactions.Meanwhile,some challenges and new perspectives of opportunities in developing catalysts and electrodes based on GDY and its analogues are also discussed.

关键词： Graphdiyne Photocatalysis Photoelectrochemical cell Heterojunction

Microstructural evolution and mechanical properties of Mg-5Y-5Gd-xNd-0.5Zr magnesium alloys at different states

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Rare Metals 2010年第3期29卷 317-322页

作者： li yongjun ZHANG Kui ZHANG Ya li Xinggang MA Minglong State Key Lab for Fabrication and Processing of Nonferrous Metals General Research Institute for Nonferrous Metals Beijing 100088 China Design & Research Institute of Baotou Steel Group Corporation Baotou 014010 China

The microstructural evolution and mechanical properties of Mg-5Y-5Gd-xNd-0.5Zr magnesium alloys at different states were studied. The results reveal that island compounds at the grain boundaries of the as-cast alloys mainly were Mg24Y5, Mg41Nd5, and Mg5Gd phases. After homogenization at 808 K for 24 h, the distribution of the island compounds became discrete and Mg5Gd phases mostly decomposed and dissolved. With hot extrusion, the grain size was refined to about 20 μm on average, and both the strength and elongation were greatly improved. After ageing at 523 K for 5 h, the strength of different extruded alloys largely increased but the elongation decreased. With the increase of neodymium content, the strength of the alloys at different states increased. The content of neodymium element had an obvious effect on the elongation of the designed alloys. In the designed alloys, the Mg-5Y-5Gd-2.2Nd-0.5Zr alloy exhibited the best combination properties and its ultimate tensile strength, yield strength, and elongation could reach 380 MPa, 285 MPa, and 9.0%, respectively.

关键词： magnesium alloys neodymium extrusion homogenization microstructural evolution mechanical properties