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A Trust Region Algorithm for Solving Bilevel Programming Problems

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Acta Mathematicae Applicatae Sinica 2013年第3期29卷 491-498页

作者： Guo-shan LIU shi-qin XU Ji-ye HAN School of Business Renmin University of China Academy of Mathematics and Systems Science Chinese Academy of Sciences

In this paper, we present a new trust region algorithm for a nonlinear bilevel programming problem by solving a series of its linear or quadratic approximation subproblems. For the nonlinear bilevel programming problem in which the lower level programming problem is a strongly convex programming problem with linear constraints, we show that each accumulation point of the iterative sequence produced by this algorithm is a stationary point of the bilevel programming problem.

关键词： Bilevel programming problem trust region algorithm global convergence mathematical program with equilibrium constraints stationary point

Local Preserving Graphs Using Intra-Class Competitive Representation for Dimensionality Reduction of Hyperspectral Image

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Journal of Beijing Institute of Technology 2021年第2期30卷 139-158页

作者： Zhen ye shihao shi Tao Sun Lin Bai School of Electronics and Control Engineering Chang’an UniversityXi’an 710064China

As a key technique in hyperspectral image pre-processing,dimensionality reduction has received a lot of ***,most of the graph-based dimensionality reduction methods only consider a single structure in the data and ignore the interfusion of multiple *** this paper,we propose two methods for combining intra-class competition for locally preserved graphs by constructing a new dictionary containing neighbourhood *** two methods explore local information into the collaborative graph through competing constraints,thus effectively improving the overcrowded distribution of intra-class coefficients in the collaborative graph and enhancing the discriminative power of the *** classifying four benchmark hyperspectral data,the proposed methods are proved to be superior to several advanced algorithms,even under small-sample-size conditions.

关键词： intra-class competition graph construction hyperspectral image dimensionality reduction

Energy Consumption and Its Influencing Factors of Iron and Steel Enterprise

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Journal of Iron and Steel Research International 2013年第8期20卷 8-13页

作者： DU Tao shi Tian LIU Yong ye Jian-bo State Environmental Protection Key Laboratory of Eco-Industry Northeastern University

Based on the theory of system energy-saving, a multilevel input-output computational model ot the iron and steel enterprise was established. And one example was calculated using this model to analyze the product energy value, the process of energy consumption and energy consumption per ton of steel of an iron and steel enterprise. The influences of factory layout, steel ratio and production structure are calculated and analyzed. The calculation example indicates that reasonable factory layout is helpful to reduce its transportation energy consumption, decrease loss of heat, improve product rate and reduce environmental contamination; ore to steel ratio and iron to steel ratio decrease at the same degree; the influence of ore to steel ratio on energy intensity per ton is less than that of iron to steel ratio. The lord process product structure has a certain effect on comprehensive energy consumption per ton of steel.

关键词： energy consumption product energy value input-output model influencing factor

Further Understanding on the Three Domains of Isotactic Polypropylene by Investigating the Crystalline Morphologies Evolution after Treatment at Different Domains

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Chinese Journal of Polymer Science 2016年第3期34卷 344-358页

作者： ding-ding hu shi-bing ye fei yu 冯嘉春 State Key Laboratory of Molecular Engineering of Polymers Collaborative Innovation Center of Polymers and Polymer Composite Materials Department of Macromoleeular Science Fudan University Shanghai 200433 China

The introduction of concept of the three domains of isotactic polypropylene（iPP） by Wittmann and Lotz et al. is an important advance in understanding the influence of the melt structures on the crystallization behaviors and consequent properties. To further understand the physical nature of the melt structures, the crystalline structures of i PP after thermal treatment in the three domains are systematically investigated. It is found that after treated at different domains the crystal morphologies, including the sizes and birefringence of spherulitic, the proportion of radial and tangential lamellae, etc., have distinctly different features. Our study reveals that the ＂nuclei＂ at domain II compose of locally ordered chains and the induced memory effect could not be erased under annealing treatment, while the ＂nuclei＂ at domain III compose of crystal fragments, which will aggregate under annealing process. Based on our results, highly schematic diagrams are proposed to illustrate the probable physical characteristics of the melt structures at the three different domains.

关键词： Polypropylene Self-nucleating Annealing Crystallization morphology

Sedimentary paleoenvironment and its control on organic matter enrichment in the Mesoproterozoic hydrocarbon source rocks in the Ordos Basin,southern margin of the North China Craton

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Petroleum Science 2024年第4期21卷 2257-2272页

作者： Zhi-Chen Wu Ju-ye shi Tai-Liang Fan Ming Jiang School of Energy Resources China University of Geosciences(Beijing)Beijing100083China Key Laboratory of Marine Reservoir Evolution and Hydrocarbon Enrichment Mechanism Ministry of EducationChina University of Geosciences(Beijing)Beijing100083China

The black shale of the Mesoproterozoic Cuizhuang Formation in the Changcheng System in Yongji city,North China Craton,is a potential source *** the organic matter enrichment mechanism is crucial for evaluating source rock resources and understanding oil and gas accumulation *** this study,we evaluated the sedimentary paleoenvironment and organic matter enrichment mechanisms of shale using thin section observations,mineral composition analysis,organic geochemistry,and elemental *** found significant differences in the sedimentary paleoenvironment and organic matter enrichment mechanisms between the lower Cuizhuang Formation and the Beidajian Formation *** Cuizhuang Formation was deposited in a late-stage,restricted basin environment during the rift phase,and elemental and geochemical indicators showed that the Cuizhuang Formation was in a suboxic-anoxic water environment,that was influenced by a warm and humid paleoclimate and submarine hydrothermal activities,which promoted the accumulation of organic ***,the enrichment of organic matter in the Cuizhuang Formation was mainly controlled by redox *** formation of suboxic-anoxic water environments may be closely related to the warm and humid paleoclimate and submarine hydrothermal *** conditions promote continental weathering and increase marine productivity,thereby consuming oxygen in the bottom ***,acidic hydrothermal activity also helps to establish an anoxic *** results reveal the effects controlling various coupled mechanisms dominated by redox conditions,which may explain the development of source rocks in the Cuizhuang Formation.

关键词： Cuizhuang formation Paleoproterozoic source rocks Marine productivity Paleoenvironments Submarine hydrothermal activity Organic matter enrichment

Regulating non-precious transition metal nitrides bifunctional electrocatalysts through surface/interface nanoengineering for air-cathodes of Zn-air batteries

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Green Energy & Environment 2022年第1期7卷 16-34页

作者： Qixing Du Yanmei gong Muhammad Arif Khan Daixin ye Jianhui Fang Hongbin Zhao Jiujun Zhang Department of Chemistry&Institute for Sustainable Energy College of SciencesShanghai UniversityShanghai200444China Department of Physics College of SciencesShanghai UniversityShanghai200444China School of Material Science and Engineering Shanghai UniversityShanghai200444China

Zn-air batteries(ZABs),especially the secondary batteries,have engrossed a great interest because of its high specific energy,economical and high ***,due to the insufficient activity and stability of bifunctional electrocatalysts for air-cathode oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)processes,the practical application of rechargeable ZABs is seriously *** the effort of developing high active,stable and cost-effective electrocatalysts,transition metal nitrides(TMNs)have been regarded as the candidates due to their high conductivity,strong corrosion-resistance,and bifunctional catalytic *** this paper,the research progress in TMNs-based material as ORR and OER electrocatalysts for ZABs is discussed with respect to their synthesis,chemical/physical characterization,and performance validation/*** surface/interface nanoengineering strategies such as defect engineering,support binding,heteroatom introduction,crystal plane orientation,interface construction and small size effect,the physical and chemical properties of TMNs-based electrocatalysts are emphasized with respect to their structures/morphologies,composition,electrical conductivity,specific surface area,chemical stability and corrosion *** challenges of TMNs-based materials as bifunctional air-cathode electrocatalysts in practical application are evaluated,and numerous research guidelines to solve these problems are put forward for facilitating further research and development.

关键词： Surface/interface nanoengineering Non-precious transition metal nitrides Zn-air batteries Oxygen reduction reaction Oxygen evolution reaction

Cross-national Perspectives on Using Sustainable Development Goals(SDGs) Indicators for Monitoring Sustainable Development: A Database and Analysis

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Chinese Geographical Science 2021年第4期31卷 600-610页

作者： WANG Xiangyu SONG Changqing CHENG Changxiu ye Sijing SHEN shi Key Laboratory of Environmental Change and Natural Disaster Ministry of EducationBeijing Normal UniversityBeijing 100875China Center for Geodata and Analysis Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China National Tibetan Plateau Data Center Beijing 100101China

Sustainable development is the theme of the 21st century. To monitor the progress of sustainable development, the United Nations launched Sustainable Development Goals(SDGs) in 2015. Subsequently, nations of the world have drawn up a list of localized indicators regarding the United Nations SDGs as a paradigm. We established a database including SDGs indicator systems of 11 economies by collecting and determining a large number of materials. Based on this database, we analyzed SDGs indicators by designing a conceptual framework of comparative analysis that included three views. We found that the SDGs indicator systems of 11 economies are different between the number of indicators, the proportion of different categories, and the connotation of indicators. Although the SDGs indicator systems among economies regarded the United Nations SDGs as a framework and included the major social problems related to sustainability, the inconsistency between SDGs indicator systems is large. It is a major reason why scholars lack the systematic method for developing indicators. There are challenges faced in data accessibility. The framework for comparative analysis could be applied to different economies.

关键词： Sustainable Development Goals(SDGs) framework indicator cross-national database

Manganese doping to boost the capacitance performance of hierarchical Co_(9)S_(8)@Co(OH)_(2) nanosheet arrays

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Green Energy & Environment 2022年第6期7卷 1289-1297页

作者： Lingxia Zheng Weiqing ye Pengju Yang Jianlan Song Xiaowei shi Huajun Zheng State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology Zhejiang University of TechnologyHangzhou310014China Department of Applied Chemistry Zhejiang University of TechnologyHangzhou310014China

Transition metal sulfides(TMSs)have been regarded as greatly promising electrode materials for supercapacitors because of abundant redox electroactive sites and outstanding ***,we report a self-supported hierarchical Mn doped Co_(9)S_(8)@Co(OH)_(2) nanosheet arrays on nickel foam(NF)substrate by a one-step metal–organic-framework(MOF)engaged approach and a subsequent sulfurization *** results reveal that the introduction of manganese endows improved electric conductivity,enlarged electrochemical specific surface area,adjusted electronic structure of Co_(9)S_(8)@Co(OH)_(2) and enhanced interfacial activities as well as facilitated reaction kinetics of *** optimal Mn doped Co_(9)S_(8)@Co(OH)_(2) electrode exhibits an ultrahigh specific capacitance of 3745 F g^(-1) at 1 A g^(-1)(5.618 F cm^(-2) at 1.5 mA cm^(-2))and sustains 1710 F g^(-1) at 30 A g^(-1)(2.565 F cm^(-2) at 45 mA cm^(-2)),surpassing most reported values on ***,a battery-type asymmetric supercapacitor(ASC)device is constructed,which delivers high energy density of 50.2 Wh kg^(-1) at power density of 800 W kg^(-1),and outstanding long-term cycling stability(94%capacitance retention after 8000 cycles).The encouraging results might offer an effective strategy to optimize the TMSs for energy-storage devices.

关键词： Mn doped Co_(9)S_(8)@Co(OH)_(2) MOF High capacitance Asymmetric supercapacitor

Effect of Stress Ratio on the Fatigue Crack Propagation Behavior of the Nickel-based GH4169 Alloy

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Acta Metallurgica Sinica(English Letters) 2017年第9期30卷 809-821页

作者： Shen ye Jian-Guo gong Xian-Cheng Zhang Shan-Tung Tu Cheng-Cheng Zhang Key Laboratory of Pressure Systems and Safety Ministry of EducationSchool of Mechanical and Power EngineeringEast China University of Science and TechnologyMeilongRoad 130Xuhui DistrictShanghai 200237People'sRepublic of China AECC Commercial Aircraft Engine Co.LTD ShanghaiEngineering Research Center for Commercial Aircraft EngineShanghai 201108People's Republic of China

The fatigue crack growth behavior of the newly developed GH4169 nickel-based alloy at a maximum stress of 700 MPa and different stress ratios was investigated in the present work employing the specimens with a single micro- notch at a frequency of 129 Hz at room temperature. The results demonstrate a typical three-stage process of fatigue crack propagation processing from the microstructurally small crack （MSC） stage to the physically small crack （PSC） stage, and finally to the long crack stage. The crack growth rate in the MSC stage is relatively high, while the crack growth rate in the PSC stage is relatively low. A linear function of crack-tip reversible plastic zone size was proposed to predict the crack growth rate, indicating an adequate prediction solution.

关键词： Fatigue crack Crack growth rate Stress ratio Nickel-based alloy