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The role of landscape pattern analysis in understanding concepts of land cover change

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Journal of Geographical Sciences 2004年第1期14卷 3-17页

作者： jerry A GRIFFITH Department of Geography University of Southern Mississippi Box 5051 Hattiesburg Mississippi 39406-5051 USA

Landscape ecology and landscape pattern analysis are important components of national-scale programs to identify trends in land cover change because: 1) Statistics on changes in land cover proportions are not spatial. A change matrix derived from GIS provides useful information, but it does not show the spatial form of change in the landscape. Landscape pattern metrics reveal spatial pattern. 2) A growing body of literature has shown that a change in landscape pattern might indicate important changes in ecological functions: forest connectivity and species movements, number and size of farm patches, effects on water quality. Spatial pattern is important in structuring ecological communities and in maintaining existence of competitors. Spatial pattern may be determined by disturbance and may in turn, determine how disturbances propagate through the system. 3) Sometimes landscape pattern may not significantly change, even though land cover proportions do change. Or, vice-versa, sometimes landscape pattern can significantly change, even though land cover proportions don't significantly change. 4) Landscape pattern is an inherent and important part of describing landscapes: based on the literature, one of the most important descriptive characteristics of a landscape is its texture. The objectives of this paper are to: 1) Explain the importance of the role of landscape ecology and landscape pattern analysis in land cover change studies; 2) Review the literature that specifically incorporates landscape ecology into land cover change studies; and 3) List the theoretical and technical issues involved and suggest solutions for them.

关键词： landscape pattern landscape monitoring landscape ecology land cover change

New directions in anxiety disorder treatment

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General Psychiatry 2019年第6期32卷 295-296页

作者： jerry Rosenbaum Department of Psychiatry Massachusetts General HospitalBostonMassachusettsUSA Department of Psychiatry Harvard Medical SchoolBostonMassachusettsUSA

As this special volume indicates,we have multiple modalities and approaches for thinking about anxiety and its *** treatment approaches and understandings vary from the psychological and cognitive to the biological and *** also assert that the underlying neurobiology,mechanisms and evolutionary psychology of anxiety are the best understood of any form of psychiatric *** while most patients who suffer anxiety disorders can be helped,few are ***,while anxiety research is robust,as evidenced in this issue,the therapies and therapeutic outcomes of today look very much the same as 30 years *** most dramatically and acutely effective of pharmacological anxiolytic treatments are limited by challenges of tachyphylaxis,diversion and abuse,and withdrawal syndromes when discontinued.

关键词： treatment directions continued

The Discontinuous Galerkin Method by Divergence-Free Patch Reconstruction for Stokes Eigenvalue Problems

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Numerical Mathematics(Theory,Methods and Applications) 2022年第2期15卷 484-509页

作者： Di Li Zhiyuan Sun Fengru Wang jerry Zhijian Yang School of Mathematics and Statistics Wuhan UniversityWuhan 430072P.R.China Institute of Applied Physics and ComputationalMathematics Beijing 100094P.R.China Computational Science Hubei Key Laboratory Wuhan UniversityWuhan 430072P.R.China

The discontinuous Galerkin method by divergence-free patch reconstruction is proposed for Stokes eigenvalue *** utilizes the mixed finite element *** patch reconstruction technique constructs two categories of approximation ***,the local divergence-free space is employed to discretize the velocity space,and the pressure space is approximated by standard reconstruction space *** from the divergence-free constraint;the identical element patch serves two approximation spaces while using the element pair Pm+1/*** optimal error estimate is derived under the inf-sup condition *** examples are carried out to validate the inf-sup test and the theoretical results.

关键词： Stokes eigenvalue problems divergence-free patch reconstruction discontinuous Galerkin mixed finite element

Practical Absorbing Boundary Conditions forWave Propagation on Arbitrary Domain

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Advances in Applied Mathematics and Mechanics 2020年第6期12卷 1384-1415页

作者： Fengru Wang jerry Zhijian Yang Cheng Yuan School of Mathematics and Statistics Wuhan UniversityWuhanHubei 430072China Computational Science Hubei Key Laboratory Wuhan UniversityWuhanHubei 430072China

This paper presents an absorbing boundary conditions(ABCs)for wave propagations on arbitrary computational *** purpose of ABCs is to eliminate the unwanted spurious reflection at the artificial boundaries and minimize the finite size *** methods are usually complicate in theoretical derivation and implementation and work only for very limited types of boundary *** contrast to other existing methods,our emphasis is placed on the ease of *** particular,we propose a method for which the implementation can be done by fitting or learning from the simulation data in a larger domain,and it is insensitive to the geometry and space dimension of the computational ***,a stability criterion is imposed to ensure the stability of the proposed *** results are presented to demonstrate the effectiveness of our method.

关键词： Absorbing boundary condition wave equations stability conditions

Li Ruqian, the Lu Xun of the Nineteenth Century

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Frontiers of Literary Studies in China-Selected Publications from Chinese Universities 2018年第2期12卷 217-253页

作者： jerry D. Schmidt Department of Asian Studies Vancouver Campus University of British ColumbiaVancouver BC Canada V6T 1Z2

This paper discusses the biography, thought, and works of Li Ruqian （1852-19o9）. He was appointed Consul in Kobe 1882-84, during which period he studied the political institutions and culture of Meiji Japan and the West, eventually translating Washington Irving＇s biography of George Washington into Classical Chinese, a book which exercised a great influence on late Qing reformers. Li＇s literary theory strongly emphasized the importance of originality. He also cultivated a style that was simpler and closer to spoken Chinese than many of his contemporaries. He eventually espoused a thoroughgoing reform of Chinese government and society. He abandoned the idea of the centrality of Chinese culture for a worldview of cultural relativity in which all cultures of the world are viewed as equally valid. After his return to China Li became even more involved in reform activities, but soon he became almost totally alienated from Chinese society and even began expressing strong doubts about the whole tradition of classical writing. In his poems and prose works, he warned Chinese intellectuals to abandon their smug conservatism and adapt to the new world or perish, making fun of his own society in biting satirical pieces that remind one of the writings of Lu Xun＇s May Fourth era. Li Ruqian may, indeed, be the first Chinese author to develop the idea of Chinese inadequacy and guilt which is so common in the literature of the next century.

关键词： Li Ruqian Zheng Zhen Shatan Group George Washington Lu Xun Chinese centrality doubting of tradition reform

The impacts of MINER Act of 2006 on the *** industry

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Journal of Coal Science & Engineering(China) 2008年第3期14卷 501-506页

作者： TIEN jerry C. Dep.of Mining and Nuclear Engineering Missouri University of Science and TechnologyRolla Missouri 65401USA

Several high-profile coal mining accidents since 2006 that killed 27 coal miners have prompted the passing of the Mine Improvement and New Emergency Response Act of 2006 (MINER Act) which was signed into law in 2006,and the proposed S-MINER Act of 2007,which passed the House of Representative in early *** four coal mining accidents are described that are believed to be responsible for both the MINER Act and proposed S-MINER Act,and their potential impacts on the *** industry.

关键词： MINERAct coal mining accident S-MINERAct fatalities mine rescue

Direct Vlasov Solvers with High-Order Spectral Element Method

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Communications in Computational Physics 2010年第6期8卷 159-184页

作者： Jin Xu Brahim Mustapha Peter Ostroumov jerry Nolen Physics Division Argonne National Laboratory9700 S.Cass Ave.ArgonneIL 60439USA Mathematics and Computer Science Division Argonne National Laboratory9700 S.Cass Ave.ArgonneIL 60439USA

This paper presents the development of parallel direct Vlasov solvers using the Spectral Element Method(SEM).Instead of the standard Particle-In-Cell(PIC)approach for kinetic space plasma simulation,*** the Vlasov-Maxwell equations,the direct method has been used in this *** are several benefits to solve the Vlasov equation directly,such as avoiding noise associated with the finite number of particles and the capability to capture the fine structure in the plasma,*** most challenging part of direct Vlasov solver comes from high dimension,as the computational cost increases as N2d,where d is the dimension of the physical *** due to fast development of supercomputers,the possibility of high dimensions becomes more realistic.A significant effort has been devoted to solve the Vlasov equation in low dimensions so far,now more interests focus on higher *** numerical methods have been tried so far,such as finite difference method,Fourier spectral method,finite volume method,*** this paper SEM has been successfully applied to construct these *** has shown several advantages,such as easy interpolation due to local element structure and long time integration due to its high order *** decomposition in high dimensions have been used for parallelization,these include scalable parallel 1D and 2D Poisson *** results have been shown and simulation results have been reported for two different cases:one dimension(1P1V),and two dimensions(2P2V)in both physical and velocity spaces.

关键词： Vlasov equation Spectral Element Method Poisson’s equation interpolation domain decomposition

Effect of single dead end entry inclination on DPM plume dispersion

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International Journal of Mining Science and Technology 2017年第3期27卷 401-406页

作者： Zheng Yi Lan Hai Thiruvengadam Magesh Tien jerry C. Li Ying Department of Mining & Nuclear Engineering Missouri University of Science and Technology (MST) Rolla MO 65401 USA Clean Air Power Inc. Poway CA 92064 USA Division of Mining and Resources Engineering Department of Civil Engineering Monash University Clayton Campus Wellington Road Clayton VIC 3800 Australia

Diesel particulate matter(DPM) is a by-product from operating diesel engines. Since diesel powers are one of the major sources of energy for mobile underground mining equipment, the adverse health effects of DPM are of a great concern. This paper used computational fluid dynamics(CFD) method to study the effect of entry inclination on DPM plume distribution in a dead end entry. An upward mining face and a downward mining face were built with a truck and a loader in loading operation close to the face area. A species transport model with incorporated buoyancy effect was used to examine the DPM dispersion pattern for the above steady-state scenarios. High DPM and temperature regions were identified for the two different faces. The model was used to assess the role of auxiliary ventilation in reducing DPM exposures of underground miners working in those entries. In this study, it is suggested to provide local ventilation at least three times of the diesel exhaust rate to be able to lower the average DPM level for the mining upward face. The requirement for local ventilation is much less for the mining downward face. This can provide guidelines for good working practices and selection of diesel emission reduction technologies underground.

关键词： Entry inclination Diesel particulate matter Computational fluid dynamics Ventilation

Modeling of the Relationship Between Pore Size Distribution and Thickness of Ceramic MF Membrane

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Chinese Journal of Chemical Engineering 1998年第3期6卷 38-48页

作者：董军航王沛徐南平时钧 jerry Y.S.Lin Department of Chemical Engineering University of Cincinnati Cincinnati Ohio OH 45221 USA

The pore size distribution(PSD)measured by the gas bubble point(GBP)method ofceramic microfiltration(MF)membranes prepared by suspension technique was found to be signifi-cantly influenced by the membrane thickness.A culm-like model for pore structure was introduced tocharacterize the membrane pores instead of the conventional model which does not reflect the radiusvariation along the pore passages and is unable to explain the thickness effect on the membrane PSD.A laminate structure,taking the culm-like model for pore structure into consideration,was hypoth-esized for ceramic MF membranes.A mathematical model was then established to quantitativelydescribe the relationship between the membrane number PSD and the membrane *** were obtained for the correlation of mean pore size and simulation of the PSD for ceramicMF membranes.

关键词： modeling pore structure pore size distribution thickness ceramic membrane