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A DIAGNOSTIC STUDY OF FEEDBACK MECHANISM IN GREENHOUSE EFFECTS SIMULATED BY NCAR CCM1

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Acta meteorologica Sinica 1994年第3期8卷 270-282页

作者：龚威周秀骥 Wang Wei-Chyung Chinese Academy of Meteorological Sciences Beijing 100081 Atmospheric Sciences Research Center State University of New York at AlbanyNew YorkU.S.A

This paper describes a diagnostic study of the feedback mechanism in greenhouse effects of increased CO_2 and oth- er trace gases(CH_4,N_2O and CFCs),simulated by general circulation *** study is based on two sensitivity exper- iments for doubled CO_2 and the inclusion of other trace gases,respectively,using version one of the community climate model(CCM1)developed at the National Centre for Atmospheric Research.A one-dimensional(1-D)and a two-dimensional(2-D)radiative-convective models are used to diagnose the feedback *** shows that the feedback factors in global and annual mean conditions are in the sequence of surface albedo,water vapor amount,water vapor distribution,cloud height,critical lapse rate and cloud cover,while in zonal and annual mean conditions in the tropical region the above sequence does not change except the two water vapor terms being the largest feedback compo- *** the feedback components,the total water vapor feedback is the largest(about 50%).The diagnosis also gives a very small feedback of either the cloud cover or the lapse rate,which is substantially different from the 1-D feedback analysis by Hansen et al.(1984).The small lapse rate feedback is considered to be partly caused by the convective adjustment scheme adopted by CCM1 model. The feedback effect for doubled CO_2 is very different from that of the addition of other trace gases because of their different vertical distributions of radiative forcing although the non-feedback responses of surface air temperature for both cases are almost the *** instance,the larger forcing at surface by the addition of other trace gases can cause stronger surface albedo feedback than by doubled CO_***,because of the negative forcing of doubled CO_2 in the stratosphere,cloud height feedback is more *** larger surface forcing in the case of other trace gases can also in- fluence atmospheric water vapor amount as well as the water vapor distribution,which will in tu

关键词： diagnostic study feedback greenhouse effect GCM simulation

Low-Rank Combined Adaptive Sparsifying Transform for Blind Compressed Sensing Image Recovery

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Chinese Journal of Electronics 2020年第4期29卷 678-685页

作者： HE Ning WANG Ruolin LYU Jiayi XUE Jian Beijing Union University Logistics Department of Beijing Military region capital Normal University University of Chinese Academic of Sciences

Compressed sensing(CS) exploits the sparsity of images or image patches in a transform domain or synthesis dictionary to reconstruct images from undegraded *** the synthesis dictionary learning methods involves NP-hard sparse coding and expensive learning steps, sparsifying transform based blind compressed sending(BCS) has been shown to be effective and efficient in applications, while also enjoying good convergence *** minimizing the rank of an overlapped patch group matrix to efficiently exploit the nonlocal self-similarity features of the image, while the sparsifying transform model imposes the local features of the *** propose a combined low-rank and adaptive sparsifying transform(LRAST) BCS method to better represent natural *** utilized the patch coordinate(PCD) descent algorithm to optimize the method, and this enforced the intrinsic local sparsity and nonlocal self-similarity of the images simultaneously in a unified *** experimental results indicated a promising performance, even in comparison to state-of-theart methods.

关键词： Low-rank Sparsifying transform Blind compressed sensing(BCS) Patch coordinate descent(PCD) Image recovery

Critical Point of Ising Films with Different Growth Directions

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Chinese Physics Letters 2000年第1期17卷 55-57页

作者： WANG Huai-yu ZHOU Yun-song D.L.Lin Department of Physics Yantai UniversityYantai 264005 Department of Physics Capital Normal UniversityBeijing 100037 Department of Physics State University of New York at BuffaloBuffaloNY 14260-1500U.S.A.

The critical temperature Tc of a spin-1/2 Ising film of cubic structures is calculated by the variational cumulant expansion method for three directions of *** results from different growth directions are analysed and compared with each *** the present model,the Tc values depend largely on the number of nearest neighbors in a monolayer for films with the same number of monolayers but grown in different *** sc,bcc and fee structures,the highest Tc is found along the(100),(110),and(111)direction,respectively.

关键词： directions Ising variational

Associations of Jet Streams with Tornado Outbreaks in the North America

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Atmospheric and Climate Sciences 2015年第3期5卷 336-344页

作者： Igor G. Zurbenko Mingzeng Sun Department of Epidemiology and Biostatistics State University of New York at Albany New York USA

Jet streams, a current of fast winds located about seven miles up near the tropopause, are major weather driving factors in the mid-latitudes. Using the Modern-Era Retrospective Analysis for Research and Applications (MERRA) reanalysis data resources for the period 1979 to 1988, we defined the latitudinal distribution of daily wind maxima by month, and analyzed latitudinal distribution of the highest daily wind speed at the selected longitude in the 19th week of the year. We showed the typical diving pattern of jet stream over Central America in spring. We found that latitudinal distribution of daily wind maxima was concurrently oscillated with latitudinal distribution of tornado outbreaks in April, May and June. KZ filter smoothed latitudinal distribution of highest daily wind speed on tornado days showed a substantial increase in number of daily wind maxima over tornado alley region, compared to that on non-tornado-days.

关键词： Jet Stream Tornado KZ Filter Specific Humidity

Jet Stream as a Major Factor of Tornados in USA

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Atmospheric and Climate Sciences 2016年第2期6卷 236-253页

作者： Igor G. Zurbenko Mingzeng Sun Department of Epidemiology and Biostatistics State University of New York at Albany New York USA

Using the Modern-Era Retrospective Analysis for Research and Applications (MERRA) reanalysis data resources for the period 1979 to 1988, we defined the spatial distribution and temporal trends of jet stream by month, and analyzed geographic distribution of the smoothed hourly wind speed of jet stream in May, after applied Kolmogorov-Zurbenko Adaptive (KZA) filter. We showed the impressive synchronousness between hourly tornado risks and diurnal distribution of top 3 maximum daily wind speed of jet stream over USA. We observed that latitudinal distribution of jet stream concurrently oscillated with latitudinal distribution of tornado outbreaks. KZA filter smoothed spatial distribution of jet stream on tornado days showed a substantial increase in presence of jet stream over tornado alley region, compared to that on non-tornado-days.

关键词： Jet Stream Tornado KZA Filter

THE BEHAVIOUR OF Mn ATOMS IMPLANTED INTO Na^+- BETA- ALUMINA SINGLE CRYSTAL

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Nuclear Science and Techniques 1990年第3期1卷 137-142页

作者：姬成周 P.Wang 单锦安郑东东 Institute of Low- Energy Nuclear Physics Beijing Normal University Beijing 100875 China The Department of Physics State University of New York at Albany Albany USA.

Upon heating, Mn atoms implanted into Na - beta- alumina diffuse inwards andoutwards with an activation energy of 0.96 eV, and substitute for Al3+ in the spinel layers of the crystal. For specimens annealed at 900 C, the optical absorption shows remarkable change in 190nm-400nm wavelength region. They fluoresce brightly green and a well- defined peak (at 525 nm) has been found in the radiative spectra.

关键词： Beta-alumina Diffusion Luminescence Ion implantation

A DYNAMIC ALLOCATION MODEL FOR MEDICAL RESOURCES IN THE CONTROL OF INFLUENZA DIFFUSION

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Journal of Systems Science and Systems Engineering 2015年第3期24卷 276-292页

作者： Ming Liu Zhe Zhang Ding Zhang Department of Management Science and Engineering Nanjing University of Science and Technology School of Business State University of New York

In this paper, we develop a unique time-varying forecasting model for dynamic demand of medical resources based on a susceptible-exposed-infected-recovered （SEIR） influenza diffusion model. In this forecasting mechanism, medical resources allocated in the early period will take effect in subduing the spread of influenza and thus impact the demand in the later period. We adopt a discrete time-space network to describe the medical resources allocation process following a hypothetical influenza outbreak in a region. The entire medical resources allocation process is constructed as a multi-stage integer programming problem. At each stage, we solve a cost minimization sub-problem subject to the time-varying demand. The corresponding optimal allocation result is then used as an input to the control process of influenza spread, which in turn determines the demand for the next stage. In addition, we present a comparison between the proposed model and an empirical model. Our results could help decision makers prepare for a pandemic, including how to allocate limited resources dynamically.

关键词： Time-varying demand medical resources influenza diffusion time-space network

Experimental study of hollow rectangular bridge column performance under vertical and cyclically bilateral loads

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Earthquake Engineering and Engineering Vibration 2013年第3期12卷 433-445页

作者： Han Qiang Du Xiuli Yihui Zhou George C. Lee Key Laboratory of Urban Security and Disaster Engineering of MOE Beijing University of Technology MCEER University at Buffalo State University of New York

To investigate the seismic performance of hollow reinforced concrete （RC） bridge columns of rectangular cross section under constant axial load and cyclically biaxial bending, five specimens were tested. A parametric study is carried out for different axial load ratios, longitudinal reinforcement ratios and lateral reinforcement ratios. The experimental results showed that all tested specimens failed in the flexural failure mode and their ultimate performance was dominated by flexural capacity, which is represented by the rupture/buckling of tensile longitudinal rebars at the bottom of the bridge columns. Biaxial force and displacement hysteresis loops showed significant stiffness and strength degradations, and the pinching effect and coupling interaction effect of both directions severely decrease the structural seismic resistance. However, the measured ductility coefficient varying from 3.5 to 5.7 and the equivalent viscous damping ratio varying from 0.19 and 0.26 can meet the requirements of the seismic design. The hollow RC rectangular bridge columns with configurations of lateral reinforcement in this study have excellent performance under bidirectional earthquake excitations, and may be considered as a substitute for current hollow RC rectangular section configurations described in the Guideline for Seismic Design of Highway Bridges （JTG/T B02-01-2008）. The length of the plastic hinge region was found to approach one sixth of the hollow RC rectangular bridge column height for all specimen columns, and it was much less than those specified in the current JTG/T. Thus, the length of the plastic hinge region is more concentrated for RC rectangular hollow bridge columns.

关键词： bridge columns hollow section cyclic loading test biaxial bending seismic performance

Two new hyperspectral indices for comparing vegetation chlorophyll content

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Geo-Spatial Information Science 2014年第1期17卷 17-25页

作者： Amy E.FRAZIER Le WANG Jin CHEN Department of Geography University at Buffalo-The State University of New YorkBuffaloNYUSA College of Resource Environment and Tourism Capital Normal UniversityBeijingChina state Key Laboratory for Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijingChina Department of Geography Oklahoma State UniversityStillwaterOKUSA

The red edge region of a hyperspectral vegetation reflectance curve provides important information regarding the biochemical and biophysical parameters of plants such as stress,senescence,and chlorophyll ***,shifts of the red edge position(REP)to longer or shorter wavelengths have also been correlated with other factors such as water content,nitrogen,and *** other factors can confuse the effect of chlorophyll on *** objective of this study is to define two new hyperspectral curve indices,the red valley width(RVW)and the chlorophyll absorption region(CAR)that are designed to provide less-sensitive characterizations of the chlorophyll content of vegetation in order to allow better comparisons among spatially or temporally distant populations of *** RVW and the CAR are both located in the visible near-infrared portion of the light spectrum and are derived from multiple hyperspectral curve features that have been found to be correlated with chlorophyll content,thus making them less sensitive to other biophysical and biochemical factors that can affect the REP *** robustness of the two new features is tested using the Leaf Optical Properties Experiment database,and the findings are used to compare two populations of saltcedar(Tamarix spp.)from a native habitat in China and an invasive habitat in the *** is a highly invasive plant species in the USA but does not pose the same ecological and economic threats in its native habitat throughout *** findings are interpreted in the context of the environmental characteristics of each region.

关键词： remote sensing spectral comparison non-native exotic species