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CHALLENGEs AND COrrEsPONDING POLICIEs FOr CHINA's UrBAN sUsTAINABLE DEVELOPMENT

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Journal of Geographical sciences 1996年第1期6卷 72-77页

作者： Gu Chaolin(Institute of Geography, CAs, Beijing 100101People’s republic of China) Inst of Geography CAS Beijing 100101 China

since the late 1970s, China's economy has been growing very fast with an average rate of over 8 percent annually. Urbanization has become the indicator of economic and secial deveopment in China. rapid growth of oromy in China pushed the process of urbanization. since 1978, China's urban non-agricultural population has grown from under 113.4 million in 1977 to 176.09 million in 1993. The number of cities increased from 188 to 617 in 1994. With urban economic activities making up an increasing share of GDP, preductivity of urban economy will heavily influence economic growth. In eastern coastal area, because economy of larger scale and agglomeration has been made more productive, the forces contributing to urban growth bome *** number of cities has increased from 78 to 247 since 1980. Urban population was over 90 million. The urbanization level reached 31.5 peed. Four megalopolises have been emerged, they are : the shanghai -Nanjing-Hangzhou region, the Pearl river Delta region, the Beijing-Tianjin- Tangshan region and the shenyang-Dalian region. According to statistics, the area of these four regions occupies about 2.6 perat of China's total territory, but their GDP has exceeded 35 percent of the country's total. However, the rapid urbanization also resulted in a series of problems on deveopment and environment.

关键词： urbanization environmental protection sustainable development urban fringe China

Thermoelastic stress Analysis of a Finite structure Containing an Asymmetrical-Oriented, Arbitrarily-shaped Hole

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Journal of Mechanics Engineering and Automation 2017年第3期7卷 145-159页

作者： s. Kurunthottikkal Philip r. E. rowlands Cummins Westport lnc (WPI) Columbus IN47201 USA Department of Mechanical Engineering University of Wisconsin-Madison Madison WI 53 706 USA

stresses, particularly those at geometric discontinuities, influence the structural integrity of engineering components. Motivated by the prevalence of complicated-shaped perforated components, the objective of this paper is to demonstrate the ability to stress analyze loaded finite members containing asymmetrical, irregularly-shaped cutouts. recognizing the difficulties in obtaining purely theoretical or numerical solutions for these situations, the paper presents an expeditious means of experimentally stress analyzing such structures. Processing the load-induced temperature information with a series representation of a stress function provides the independent stress components reliably full-field, including on the edge of a hole. The stresses satisfy equilibrium and strains satisfy compatibility. In addition to being able to stress analyze complicated shapes using real, rather than complex variables, the technique is significant in which it smooths the recorded thermal information, is widely applicable, and requires neither differentiating the measured data nor knowing the elastic properties or external boundary conditions. The latter is extremely important since the external loading is often unknown in practice. That the approach provides the independent stresses is also significant since fatigue analyses and strength criteria typically necessitate knowing the individual components of stress. Present results are supported by those from a finite element analysis, strain gage measurements and load equilibrium.

关键词： Irregular cutouts stresses thermoelastic stress analysis finite structure.

Model with strong γ_4 T-violation

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Chinese Physics C 2008年第12期32卷 939-944页

作者： r. Friedberg T. D. Lee Physics Department Columbia University New York NY 10027 U.S.A. China Center of Advanced science and Technology (CCAsT/World Lab.) P.O. Box 8730

eAbstract We extend the T violating model of the paper on ＂Hidden symmetry of the CKM and neutrinomapping matrices＂ by assuming its T-violating phases X↑ and X↓ to be large and the same, with X = X↑ = X↓. In this case, the model has 9 real parameters： aT, α↑,β↑,ξ↑,η↑T for the T-quark sector, α↓,β↓,ξ↓,η↓, for the sector and a common X- We examine whether these nine parameters are compatible with ten observables： the six quark masses and the four real parameters that characterize the CKM matrix （i.e., the Jarlskog invariant and three Eulerian angles）. We find that this is possible only if the T violating phase X is large, between -120^o to -135^o. In this strong T violating model, the smallness of theJarlskog invariant 3 × 10^-5 ismainly accounted for by the large heavy quark masses, with mc/mt〈ms/mb≈0.02, as well as the near completeoverlap of t and b quark, with （c｜b）=-0.04.

关键词： Jarlskog invariant CKM matrix strong γ4 T-violation

Investigation of Li-ion transport in Li7P3s11 and solid-state lithium batteries

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Journal of Energy Chemistry 2019年第11期28卷 1-7页

作者： Chuang Yu swapna Ganapathy Ernst r.H.van Eck Lambert van Eijck Niek de Klerk Erik M.Kelder Marnix Wagemaker Department of radiation science and Technology Delft University of TechnologyMekelweg 152629JB Delftthe Netherlands Institute for Molecules and Materials Radboud University NijmegenHeyendaalseweg 1356525 AJ Nijmegenthe Netherlands

The high Li-ion conductivity of the Li7P3s11 sulfide-based solid electrolyte makes it a promising candidate for all-solid-state lithium batteries. The Li-ion transport over electrode-electrolyte and electrolyteelectrolyte interfaces, vital for the performance of solid-state batteries, is investigated by impedance spectroscopy and solid-state NMr experiments. An all-solid-state Li-ion battery is assembled with the Li7P3s11 electrolyte, nano-Li2s cathode and Li-In foil anode, showing a relatively large initial discharge capacity of 1139.5 m Ah/g at a current density of 0.064 m A/cm^ 2 retaining 850.0 m Ah/g after 30 cycles. Electrochemical impedance spectroscopy suggests that the decrease in capacity over cycling is due to the increased interfacial resistance between the electrode and the electrolyte. 1D exchange ^7Li NMr quantifies the interfacial Li-ion transport between the uncycled electrode and the electrolyte, resulting in a diffusion coefficient of 1.70(3) ×10^-14cm^2/s at 333 K and an energy barrier of 0.132 e V for the Li-ion transport between Li2s cathode and Li7P3s11 electrolyte. This indicates that the barrier for Li-ion transport over the electrode-electrolyte interface is small. However, the small diffusion coefficient for Li-ion diffusion between the Li2s and the Li7P3s11 suggests that these contact interfaces between electrode and electrolyte are relatively scarce, challenging the performance of these solid-state batteries.

关键词： Li7P3s11 Li-ion transport spin-lattice NMr Exchange NMr solid-state battery

Fiber Cavity ring-Down Using an Optical Time-Domain reflectometer

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Photonic sensors 2014年第4期4卷 295-299页

作者： D. J. PAssOs s. O. sILVA J. r. A. FErNANDEs M. B. MArQUEs O. FrAZAO INEsC Porto Rua do Campo Alegre 687 4169-007 Porto Portugal and Dept. de Fisica e Astronomia da Faculdade deCiOncias da Universidade do Porto Rua do Campo Alegre 687 4169-007 Porto Portugal Departamento de Fisica Escola de Ci~ncias e Tecnologia Universidade de Tr6s-os-Montes e Alto Douro Quinta dePrados 5001-801 Vila Real Portugal

This work presented a demonstration of the potential for a fiber based cavity ring-down （CrD） using an optical time-domain reflectometer （OTDr）. The OTDr was used to send the impulses down into about 20km of a standard single optical fiber, at the end of which the fiber cavity ring-down was placed. The OTDr measured no appreciable losses, so other CrDs multiplexed could be spliced in parallel along the same optical fiber. To demonstrate the behavior and sensitivity of the proposed configuration, a displacement sensor based on a fiber taper with a diameter of 50 μm was placed inside the fiber loop, and the induced losses were measured on the CrD signal -- a sensitivity of 11.8 ＋ 0.5 μs/mm was achieved. The dynamic range of the sensing head used in this configuration was about 2 mm. Finally, this work was also compared with different works published in the literature.

关键词： Optical fiber sensors cavity ring-down OTDr

soil Properties as influenced by incorporation of Cropresidnes

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Pedosphere 1994年第3期4卷 209-215页

作者： A. sCAGNOZZI, r. LEVI-MINZI, A. sAVIOZZI and r. rIFFALDIInstttute of Agricultural Chemistry, University of Pisa, Via s. Michele degli scalzi 2, 56124 Pisa (Italy)

Chemical transformation , nutrient release and changes in the energy content of decomposing rape,sunflower and soybean residues confined in buried fiberglass bags were assessed in a laboratory study duringa 340-day incubation period. The organic C decreased by about 70% while total N, after initial decay,remained almost constant for each type of residue. The NH￣+sub>4sub>-N was progressively oxidized and, consequently,the NO￣-sub>3sub>N increased. The C/N ratio narrowed with loss of C. Hemicellulose, cellulose and lignin decreasedwith different trends for each crop residue. The energy content, was reduced to about 25% in rape, 30% insunflower and 20% in soybean residues. Total P, K, Ca and Mg contents decreased for each type of *** results suggest that the three residues could improve the nutrient pool of the soil.

关键词： bags crop residues organic matter decomposition soil properties

The AiiDA-KKr plugin and its application to highthroughput impurity embedding into a topological insulator

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npj Computational Materials 2021年第1期7卷 108-116页

作者： Philipp rüßmann Fabian Bertoldoand stefan Blügel Peter Grünberg Institut and Institute for Advanced simulation Forschungszentrum Jülich and JARAD-52425 JülichGermany

The ever increasing availability of supercomputing resources led computer-based materials science into a new era of highthroughput ***,Pizzi et *** the AiiDA framework that provides a way to automate calculations while allowing to store the full provenance of complex workflows in a *** present the development of the AiiDA-KKr plugin that allows to perform a large number of ab initio impurity embedding calculations based on the relativistic full-potential Korringa-Kohn-rostoker Green function *** capabilities of the AiiDA-KKr plugin are demonstrated with the calculation of several thousand impurities embedded into the prototypical topological insulator *** results are collected in the JuDiT database which we use to investigate chemical trends as well as Fermi level and layer dependence of physical properties of *** includes the study of spin moments,the impurity’s tendency to form in-gap states or its effect on the charge doping of the *** properties depend on the detailed electronic structure of the impurity embedded into the host crystal which highlights the need for ab initio calculations in order to get accurate predictions.

关键词： method topological embedding

reconstruction of a pre-rodinia supercontinent: New advances and perspectives

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Chinese science Bulletin 2002年第19期47卷 1585-1588页

作者： s.A.Wilde 2.Department of Aplied Geology Curtin University of Technology

The global collisional orogenic events (e.g. Grenvil-lian or Pan-African event) have occurred for several times since 2.5 billion years (Ga) ago, which has led Earth scientists to speculate that continental landmasses have periodically assembled and dispersed, resulting in the assembly and breakup of supercontinent. In the last decade, the reconstruction of ancient supercontinents has been focused on rodinia, a defined supercontinent that was assembled along the -1.0 Ga "Grenvillian" oro-gens. In reconstructing rodinia, however, Earth scientists have noticed that not all continental blocks in the supercontinent were welded by the -1.0 Ga orogenic belts (fig. 1(a)), and that most blocks welded by the 1.0 Ga orogens contain abundant evidence that they are a

关键词： New advances and perspectives reconstruction of a pre-rodinia supercontinent

A Novel PsO Algorithm for Optimal Production Cost of the Power Producers with Transient stability Constraints

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Journal of Electromagnetic Analysis and Applications 2009年第4期1卷 265-274页

作者： M. ANITHA s. sUBrAMANIAN r. GNANADAss Department of Electrical Engineering Annamalai University Department of Electrical & Electronics Engineering Pondicherry Engineering College

The application of a novel Particle swarm Optimization (PsO) method called Fitness Distance ratio PsO (FDr PsO) algorithm is described in this paper to determine the optimal power dispatch of the Independent Power Producers (IPP) with linear ramp model and transient stability constraints of the power producers. Generally the power producers must respond quickly to the changes in load and wheeling transactions. Moreover, it becomes necessary for the power producers to reschedule their power generation beyond their power limits to meet vulnerable situations like credible contingency and increase in load conditions. During this process, the ramping cost is incurred if they violate their permissible elastic limits. In this paper, optimal production costs of the power producers are computed with stepwise and piecewise linear ramp rate limits. Transient stability limits of the power producers are also considered as addi-tional rotor angle inequality constraints while solving the Optimal Power Flow (OPF) problem. The proposed algo-rithm is demonstrated on practical 10 bus and 26 bus systems and the results are compared with other optimization methods.

关键词： Optimal Power Flow Production Cost ramping Cost Fitness Distance ratio Particle swarm Optimization Transient stability Limit Piecewise Linear ramp rate Limit