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Potential wells for classical acoustic waves

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Science China(Physics,Mechanics & Astronomy) 2014年第1期57卷 104-112页

作者： CHEN Shi lin ShuYu mo RunYang FU ZhiQiang Applied Acoustics Institute Shaanxi Normal University Shaanxi Key Laboratory of Ultrasound

The acceleration theorem of Bloch waves is utilized to construct random potential wells for classical acoustic waves in systems composed of alternating‘cavities’and‘couplers’.One prominent advantage of this method is these‘cavities’and‘couplers’are all monolayer *** allows forming more compact classical potential wells,which leads to the miniaturization of acoustic *** systematically investigate properties of harmonic,tangent,hyperbolic function,and square classical potential wells in quasi-periodic *** show these classical potential wells are analogues of quantum potential *** some technologies and concepts in quantum potential well fields may be generalized to classical acoustic wave *** addition,some abnormal cases regarding forming classical potential wells are also found.

关键词： classical potential wells phonon engineering acceleration theorem of Bloch waves localized eigenmodes

THE ASYMPTOTIC BEHAVIOR OF SOLUTION FOR THE SINGULARLY PERTURBED INITIAL BOUNDARY VALUE PROBLEMS OF THE REACTION DIFFUSION EQUATIONS IN A PART OF DOMAIN

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Applied Mathematics and Mechanics(English Edition) 2001年第10期22卷 1192-1197页

作者： LIU Qi-lin(刘其林) mo Jia-qi(莫嘉琪) Department of Mathematics Nanjing University Nanjing 210093 P R China Department of Mathematics Huzhou Teachers CollegeHuzhou 313000 P R China

A class of singularly perturbed initial boundary value problems for the reaction diffusion equations in a part of domain are considered. Using the operator theory the asymptotic behavior of solution for the problems i... 详细信息

关键词： singular perturbation reaction diffusion equation initial boundary value problem

Dynamics and Responses of Vegetation to Climatic Variations in Ziya- Daqing Basins, China

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Chinese Geographical Science 2016年第4期26卷 478-494页

作者： HUANG Farong mo Xingguo lin Zhonghui HU Shi Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China

Examining the direct and indirect effects of climatic factors on vegetation growth is critical to understand the complex linkage between climate change and vegetation dynamics. Based on the moderate Resolution Imaging Spectroradiometer(moDIS) Normalized Difference Vegetation Index(NDVI) data and meteorological data(temperature and precipitation) from 2001 to 2012, the trend of vegetation dynamics were examined in the Ziya-Daqing basins, China. The path analysis was used to obtain the information on the relationships among climatic factors and their effects on vegetation growth. It was found that the trends of growing season NDVI were insignificant in most plain dry land, while the upward trends were significant in forest, grass and dry land in Taihang mountains. According to the path analysis, in 23% of the basins the inter-annual NDVI variation was dominated by the direct effect of precipitation, in 5% by the direct effects of precipitation and temperature, and in less than 1% by the direct effect of temperature or indirect effects of these two climatic factors. It indicated that precipitation significantly affected the vegetation growth in the whole basins, and this effect was not regulated by temperature. Precipitation increase(especially in July, August and September) was favorable to greenness enhancement. Summer temperature rising showed negative effect on plant productivity enhancement, but temperature rise in April was beneficial for the vegetation growth. When April temperature increases by 1℃, the onset date of greenness for natural vegetation will be 2 days in advance. There was a lag-time effect of precipitation or temperature on monthly NDVI for all land use types except grass.

关键词： Normalized Difference Vegetation lndex (NDVI) phenology climate variation direct effect indirect effect

Microstructure and mechanical properties of WC-20wt% Co/ZrO_2(3Y)cermet composites

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Journal of University of Science and Technology Beijing 2006年第2期13卷 174-177页

作者： lin An Jingtao han Jan Chen Materials Science and Engineering School University of Science and Technology Beijing Beijing 100083 China Shougang Dongxing Industry Corporation Yantan 264006 China

The cermet composites WC-20wt%Co/ZrO2（E6）with four different comtents of ZrO2（3Y）were prepared by normal vacuum sinter processing;the optical microscope and SEMwere used to characterize their *** *** strength and impact toughness of the specimens were *** experimental results show that ZrO2（3Y） particles in WC-20wt%Co matrix are sphcrical particles in different sizes which are distributed uniformly in Co phases and WC phases,the bending strength and impact toughness of the WC-20wt%Co cermet composites added ZrO2（3Y）improve *** the hardness values have little change.

关键词： ZrO2(3Y) cermet composites mechanical properties microstructure normal vacuum sinter

Innovative construction of macroporous–mesoporous structured spherical alumina and its hydrothermal stability

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Particuology 2024年第7期90卷 429-435页

作者： Yufan mo Chunli Li Huiyu Li Wei han He Wen Yinghong han Chunxia Che Yongjun Feng State Key Laboratory of Chemical Resource Engineering Beijing Engineering Center for Hierarchical CatalystsCollege of ChemistryBeijing University of Chemical TechnologyBeijing100029China Lanzhou Petrochemical Research Center Petrochemical Research InstitutePetroChinaLanzhou730060China

The pore structure of spherical alumina supports is closely related to the dispersion of catalytically active components and the diffusion of *** excellent pore structure under strict reaction conditions is of utmost *** this work,sphericalγ-Al_(2)O_(3)support with a bimodal pore structure,composed of macropores and mesopores,was successfully synthesized using dodecane as the pore-forming agent through the oil–ammonia column-shaping *** morphology and internal pore structure of the alumina were found to be influenced by the amount of surfactant added and ultrasound treatment ***,when concentration of surfactant was 4‰and ultrasound voltage of 20 V was applied,the resultingγ-Al_(2)O_(3)-4‰-20 displayed a highly concentrated distribution of macropores with an average pore size of 100 nm,resulting in an impressive porosity of 69.21%.In contrast,the untreated sample ofγ-Al_(2)O_(3)-0-0 only exhibited a mesoporous distribution with a porosity of 54.03%.moreover,after being subjected to a hydrothermal treatment in a high temperature(600°C)and high humidity(water vapor)environment for 120 h,theγ-Al_(2)O_(3)-4‰-20 sample maintained a high BET specific surface area of 170.9 m^(2)g^(−1)and mercury intrusion porosimetry specific surface area of 263.3 m^(2)g^(−1).

关键词： Spherical alumina supports Pore-forming agent Oil-ammonia column shaping method Hydrothermal treatment Hydrothermal stability

Erector Spinae Plane Block Combined with Serratus Anterior Plane Block Versus Thoracic Paravertebral Block for Postoperative Analgesia and Recovery After Thoracoscopic Surgery:A Randomized Controlled Non-inferiority Clinical Trial

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Current Medical Science 2023年第3期43卷 615-622页

作者： Xuan mo Tao JIANG han WANG Yi ZhanG Department of Anesthesiology Hubei Key Laboratory of Geriatric Anesthesia and Perioperative Brain Healthand Wuhan Clinical Research Center for Geriatric AnesthesiaTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Objective This study aimed to compare the postoperative analgesia and recovery of ultrasound-guided erector spinae plane block combined with serratus anterior plane block(ESPB combined with SAPB)versus thoracic paravertebral block(PVB)after thoracoscopic *** Ninety-two patients who underwent video-assisted thoracoscopic surgery(VATS)were randomly divided into group S(n=46)and group P(n=46).After anesthesia induction,the same anesthesiologist performed ultrasound-guided ESPB at T5 and T7 levels combined with SAPB at the level of the fifth rib in the midaxillary line in group S and ultrasound-guided PVB at T5 and T7 levels in group *** in both groups were given 40 mL of 0.4%***-six patients completed the study(group S,n=44;group P,n=42).The morphine consumption,visual analogue scale(VAS)scores at rest and coughing,and frequency of remedial analgesia were recorded at 1,2,4,8,and 24 h *** function parameters were recorded at 1,4,and 24 h postoperatively,and the quality of recovery(QoR)-15 score at 24 h *** adverse effects,duration of chest tube drainage and length of stay were also *** The morphine consumption at postoperative 4 and 8 h and the incidence of ipsilateral shoulder pain(ISP)were significantly lower in group S than in group *** QoR-15 questionnaire score at postoperative 24 h was significantly lower in group P than in group S(Pmorphine consumption was lower at 24 h postoperatively in group S than in group P,with no significant difference found *** morphine consumption at other observed times,VAS scores,pulmonary function parameters,frequency of remedial analgesia,duration of chest tube drainage,length of stay,and incidence of other adverse events were comparable between group S and group *** Ultrasound-guided ESPB combined with SAPB is non-inferior to PVB in terms of morphine consumption at postoperative 24 h and postoperative ***,this appr

关键词： erector spinae plane block serratus anterior plane block thoracic paravertebral block postoperative analgesia postoperative recovery

Periodical Oscillations of Supercurrent Fluctuation in Mesoscopic Josephson Junctions in Quantized Electromagnetic Fields

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Chinese Physics Letters 1996年第5期13卷 359-361页

作者： KUANG Le-man WANG Yi-wen GE mo-lin Theoretical Physics Division Nankai Instilute of MathematicsTianjin 300071 Department of Physics Hu'nan Normal UriiversityChangsha 410081

Supercurrent fluctuation of a mesoscopic Josephson jutiction(MJJ)in the presence of a de static voltage and a time-varying quantized electromagnetic field(QEMF)is *** is shown thm the fluctuation of supercurrent in the MJJ exhibits periodical oscillations with a periodicity shich depends upon the rate of the classical static external voltage and the frequency of the QEMF.

关键词： Josephson Electromagnetic Periodical

Variational iteration solving method for El Nio phenomenon atmospheric physics of nonlinear model

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Acta Oceanologica Sinica 2005年第5期24卷 35-38页

作者： mo Jiaqi WANG Hui lin Wantao lin Yihua Anhui Normal University Wuhu 241000 China Division of Computional Science E-Institute of Shanghai Universities Shanghai Jiaotong University Shanghai 200240 China Chinese Academy of Meteorological Sciences Beijing 100081 China State Laboratory of Numerical modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmosheric Physics Chinese Academy of Sciences Beijing 100029 China

A class of E1 Niйo atmospheric physics oscillation model is considered. The E1 Niйo atmospheric physics oscillation is an abnormal phenomenon involved in the tropical Pacific ocean-atmosphere interactions. The conceptual oscillator model should consider the variations of both the eastern and western Pacific anomaly patterns. An E1 Niйo atmospheric physics model is proposed using a method for the variational iteration theory. Using the variational iteration method, the approximate expansions of the solution of corresponding problem are constructed. That is, firstly, introducing a set of functional and accounting their variationals, the Lagrange multiplicators are counted, and then the variational iteration is defined, finally, the approximate solution is obtained. From approximate expansions of the solution, the zonal sea surface temperature anomaly in the equatorial eastern Pacific and the thermocline depth anomaly of the sea-air oscillation for E1 Niйo atmospheric physics model can be analyzed. E1 Niйo is a very complicated natural phenomenon. Hence basic models need to be reduced for the sea-air oscillator and are solved. The variational iteration is a simple and valid approximate method.

关键词： nonlinear variational iteration method E1 Niйo phenomenon

Artistic Augmentation of Photographs with Droplets

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Journal of Computer Science & Technology 2019年第6期34卷 1294-1306页

作者： mo-han Zhang Jin-Hui Yu Kang Zhang Jun-Song Zhang State Key Laboratory of CAD&CG Zhejiang UniversityHangzhou 310027China Department of Computer Science Harbin Finance UniversityHarbin 150030China Department of Computer Science The University of Texas at DallasRichardsonTX 75080-3021U.S.A. Faculty of Information Technology Macao University of Science and TechnologyMacao 999078China National Engineering Research Center for E-Learning Central China Normal UniversityWuhan 430079China

Artistic augmentation of photographs with water droplets aims at generating aesthetic yet realistic images, and thus differs from traditional augmented reality in two aspects. One difference lies in the adoption of a new image as the environment map in order to render reflected or refracted effects on the surface of inserted water droplets. The other difference is in modeling of water droplets including hanging droplets and resting droplets. These differences raise two research challenges:(1) how to adjust the brightness and colors of the new environment map to maintain visual consistency between the new environment map and the original input image;(2) how to model hanging and resting droplets aesthetically. This paper proposes a framework that addresses these two challenges and demonstrates the effectiveness of our framework by generating example augmented images.

关键词： artistic augmentation augmented reality illumination estimation droplet modeling image-based modeling