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Coordinating control of multiple rigid bodies based on motion primitives

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Acta Mechanica Sinica 2012年第2期28卷 482-489页

作者： Fan Wu Zhi-yong geng State Key Laboratory for Turbulence and Complex Systems Peking University100871 BeijingChina

This paper studies the problem of coordinated motion generation for a group of rigid bodies. Two classes of coordinated motion primitives, relative equilibria and ma- neuvers, are given as building blocks for generating coordi- nated motions. In a motion-primitive based planning frame- work, a control method is proposed for the robust execution of a coordinated motion plan in the presence of perturba- tions. The control method combines the relative equilibria stabilization with maneuver design, and results in a close- loop motion planning framework. The performance of the control method has been illustrated through a numerical sim- ulation.

关键词： Coordinating control Motion plan execution Motion primitive. Relative equilibrium. Maneuver

Municipal solid waste management in Dalian： practices and challenges

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Frontiers of Environmental Science & Engineering 2012年第4期6卷 540-548页

作者： Xinbei WANG yong geng Institute of Applied Ecology Chinese Academy of ScienceShenyang 110016China

The fast growing of urban areas in developing countries has brought serious problems on municipal solid waste （MSW） management. It will be rational to adopt an integrated approach to deal with such a challenge so that the overall eco-efficiency of MSW management could be improved. To better examine how attributes of integrated MSW management are being interpreted and put into practice, and to explore what changes should be made to improve the application of integrated MSW management, we employ a case study method so that lessons learned could be used to inform initiatives in other cities and the potential solution may offer feasible strategies. The case study city is Dalian, a typical seaport city with fast growing rate in economy. The outcomes of this case study show us that fragmented management structure, ineffective and inefficient enforcement of relevant regulations, backward technologies, limited financial resources and lack of public participation are main barriers for the implementation of integrated MSW management. Consequently, in order to overcome these barriers, we propose an integrated management framework on MSW management, aiming to maximize the overall eco-efficiency of MSW management.

关键词： municipal solid waste (MSW) management 3R principles challenges eco-efficiency effective and efficient enforcement

Global Smooth Solutions to Relativistic Euler-Poisson Equations with Repulsive Force

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Acta Mathematicae Applicatae Sinica 2014年第4期30卷 1025-1036页

作者： yong-cai geng Lei WANG Department of Mathematics Shanghai Institute of Technology Wuxi Teachers' College

In this paper, we are concerned with the global existence of smooth solutions for the one dimen- sional relativistic Euler-Poisson equations： Combining certain physical background, the relativistic Euler-Poisson model is derived mathematically. By using an invariant of Lax＇s method, we will give a sufficient condition for the existence of a global smooth solution to the one-dimensional Euler-Poisson equations with repulsive force.

关键词： relativistic Euler equations relativistic Euler-poisson equations global existence characteristic-based method

Spatiotemporal evolution and driving factors for GHG emissions of aluminum industry in China

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Frontiers in Energy 2023年第2期17卷 294-305页

作者： Chao TANG yong geng Xue RUI Guimei ZHAO School of Environmental Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China China Institute for Urban Governance School of International and Public AffairsShanghai Jiao Tong UniversityShanghai200030China SJTU-UNIDO Joint Institute of Inclusive and Sustainable Industrial Development School of International and Public AffairsShanghai Jiao Tong UniversityShanghai200030China School of Finance and Economics Jiangsu UniversityZhenjiang212013China

China’s aluminum(Al)production has released a huge amount of greenhouse gas(GHG)*** one of the biggest country of primary Al production,China must mitigate its overall GHG emission from its Al industry so that the national carbon neutrality target can be *** such a background,the study described in this paper conducts a dynamic material flow analysis to reveal the spatiotemporal evolution features of Al flows in China from 2000 to *** analysis is also performed to uncover the driving factors of GHG emission generated from the Al *** major findings include the fact that China’s primary Al production center has transferred to the western region;the primary Al smelting and carbon anode consumption are the most carbonintensive processes in the Al life cycle;the accumulative GHG emission from electricity accounts for 78.14% of the total GHG emission generated from the Al industry;China’s current Al recycling ratio is low although the corresponding GHG emission can be reduced by 93.73% if all the primary Al can be replaced by secondary Al;and the total GHG emission can be reduced by 88.58% if major primary Al manufacturing firms are transferred from Inner Mongolia to *** upon these findings and considering regional disparity,several policy implications are proposed,including promotion of secondary Al production,support of clean electricity penetration,and relocation of the Al industry.

关键词： aluminum material flow analysis GHG(greenhouse gas)emissions LMDI(logarithmic mean divisa index)

Effects of aging treatment on microstructure and mechanical properties of Cr25Ni35Nb and Cr35Ni45Nb furnace tube steel

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Acta Metallurgica Sinica(English Letters) 2011年第3期24卷 235-242页

作者： Limin SHEN Jianming GONG yong JIANG Luyang geng College of Mechanical and Power Engineering Nanjing University of Technology Nanjing 210009 China

Cr25Ni35Nb and Cr35Ni45Nb alloys are usually used in the ethylene cracking furnaces. However, premature failure of furnace tubes often occurs ahead of design life due to elevated temperature exposure conditions （1050-1100 ℃） and aggressive service environment. Effects of exposure temperature and time on microstructure and mechanical properties of Cr25Ni35Nb and Cr35Ni45Nb steel at aging temperature （1200 ℃） with various exposure time were simulated different service times at 1050 ℃. Change of mechanical properties at room temperature and elevated temperature （900 ℃） of the aged Cr25Ni35Nb and Cr35Ni45Nb steel were investigated. Under exposure at 1200 ℃, ultimate tensile and yield strength, elongation of Cr35Ni45Nb steel increase initially and then decrease, however, strength and ductility of Cr25Ni35Nb steel decrease with aging time increasing. Large amount of fine secondary carbide particles precipitated and dispersed in matrix of Cr35Ni45Nb steel, which increased strength and ductility for dispersion strengthening. However, the effect of the dispersion strengthening is weakened by needle-like secondary carbides. Strength and ductility decreased with fine secondary carbide particles growing. For Cr25Ni35Nb steel, few fine secondary carbide particles precipitated and dispersed in the matrix, and needle-like secondary carbides generated in the matrix, which causes strength and ductility decreased with aging time increasing.

关键词： Aging treatment Furnace tube steel Mechanical property Microstructure Cr25Ni35Nb Cr35Ni45Nb

Existence and Nonexistence of Global Positive Solutions for a Weakly Coupled P-Laplacian System

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Acta Mathematicae Applicatae Sinica 2013年第3期29卷 541-554页

作者： Xian-zhong ZENG Zhen-hai LI yong-geng GU School of Mathematics and Computing Science Hunan University of Science and Technology College of Science Guangxi University for Nationalities Department of Mathematics Hunan Normal University

In this paper, we deal with a weakly coupled evolution P-Laplacian system with inhomogeneous terms. We obtain a critical criterion concerning existence and nonexistence of its global positive solutions. Such a criterion is different from that of the weakly coupled evolution P-Laplacian system with homogeneous terms. Further, we demonstrate existence and nonexistence of its global positive solutions.

关键词： the evolution P-Laplacian system inhomogeneous terms blow-up global existence

Accounting greenhouse gas emissions of food consumption between urban and rural residents in China: a whole production perspective

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Frontiers in Energy 2022年第2期16卷 357-374页

作者： Yanfeng XU yong geng Ziyan GAO Shijiang XIAO Chenyi ZHANG Mufan ZHUANG China-UK Low Carbon College Shanghai Jiao Tong UniversityShanghai 200240China School of International and Public Affairs Shanghai Jiao Tong UniversityShanghai 200030China China Institute for Urban Governance Shanghai Jiao Tong UniversityShanghai 200030China School of Environmental Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Management China University of Mining and TechnologyXuzhou 221116China

Food consumption is necessary for human *** a global scale,the greenhouse gas(GHG)emission related to food consumption accounts for 19%–29%of the total GHG *** has the largest population in the world,which is experiencing a rapid *** the background of urbanization and the adjustment of the diet structure of Chinese residents,it is critical to mitigate the overall GHG emission caused by food *** study aims to employ a single-region input-output(SRIO)model and a multi-regional input-output(MRIO)model to measure GHG emission generated from food consumption in China and compare the contributions of different industrial sectors,uncovering the differences between urban and rural residents and among different provinces(autonomous regions/municipalities),as well as identifying the driving forces of GHG emission from food consumption at a national *** results indicate that the total GHG emission generated from food consumption in China tripled from 157 Mt CO_(2)e in 2002 to 452 Mt CO_(2)e in *** fastest growing GHG emission is from the consumption of other processed food and meat *** GHG emissions from both urban and rural residents increased,the gap between them is ***,processing and manufacture of food,manufacture of chemical and transportation,storage and post services sectors are key sectors inducing food consumption related GHG *** a regional perspective,the top five emission provinces(autonomous regions/municipalities)include Shandong,Hubei,Guangdong,Zhejiang,and *** on such results,policy recommendations are proposed to mitigate the overall GHG emission from food consumption.

关键词： greenhouse gas(GHG)emission food consumption industry sectors mitigation measures urban governance

Uncovering CO_(2) emission drivers under regional industrial transfer in China’s Yangtze River Economic Belt: a multi-layer LMDI decomposition analysis

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Frontiers in Energy 2021年第2期15卷 292-307页

作者： Huijuan JIANG yong geng Xu TIAN Xi ZHANG Wei CHEN Ziyan GAO China-UK Low Carbon College Shanghai Jiao Tong UniversityShanghai 200240China School of International and Public Affairs Shanghai Jiao Tong UniversityShanghai 200240China China Institute for Urban Governance Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China School of Environmental Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Geography and Environment Shandong Normal UniversityJinan 250358China

With the relocation of heavy industries moving from downstream region to upstream and midstream regions in the Yangtze River Economic Belt(YREB),it is critical to encourage coordinated low carbon development in different regions within the *** paper uncovers the evolution of CO_(2) emissions in different regions within the YREB for the period of 2000–*** decomposes regional CO_(2) emission changes using the temporal and cross-regional three-layer logarithmic mean Divisia index(LMDI)***,it decomposes industrial CO_(2) emission changes using the temporal two-layer LMDI *** research results show that economic growth is the major driver for regional CO_(2) emission *** mitigation drivers,such as energy intensity and energy structure,lead to a more decreased CO_(2) emission in the downstream region than in the upstream and midstream *** addition,it proposes several policy recommendations based upon the local realities,including improving energy efficiency,optimizing energy structure,promoting advanced technologies and equipment transfers,and coordinating the development in the upstream,midstream and downstream regions within the YREB.

关键词： CO_(2)emission multi-layer LMDI decomposition industrial transfer governance

Anthropogenic mineral generation and its potential resource supply:The case of niobium

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Science China Earth Sciences 2024年第8期67卷 2583-2591页

作者： Xianlai ZENG Moisés Gómez Mahmoud BAKRY yong geng Jinhui LI School of Environment Tsinghua UniversityBeijing 100084China School of Environmental Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of International and Public Affairs Shanghai Jiao Tong UniversityShanghai 200030China

The strategy of carbon neutrality is reshaping the global landscape of resource flow and *** the final sink of geological minerals,the proliferated anthropogenic minerals,also called secondary resources,play an increasingly important role in resource supply *** is a critical metal that lacks full concern for its *** fundamental principle of niobium circularity is to recycle and maintain the material as close to the manufacturing process as *** we estimate the niobium-containing applications lost at their end-of-life,underscoring the imperative to minimize such ***,we elucidate the extraction processes for scrap and alloy quantities throughout the industry's *** from anticipated waste generated by the majority of niobium applications,a forecast indicates a potential loss of approximately 168 kt by 2090 in the absence of ***,with a recycling efficiency of 90%for niobium,the projected loss diminishes to approximately 16 *** delve into the significance of niobium's circular economy and explore various aspects that demand further investigation for a seamless transition from linear to circular practices.

关键词： Niobium Anthropogenic mineral Circular economy Recycling Sustainability