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任意圆弧形凸起地形中隧洞对入射平面SH波的影响

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地震学报 2004年第5期26卷 495-508页

作者：梁建文罗昊 vincent w.lee 天津大学土木工程系 Department of Civil Engineering University of Southern California Los Angeles CA 90089-2531 U.S.A.

借助辅助函数的思想 ,采用波函数展开法给出了圆弧形凸起地形中隧洞对入射平面SH波影响问题的一个解析解 .数值结果表明 ,凸起地形中隧洞的存在以及隧洞大小 ,对凸起地形表面运动 ,以及凸起地形中的隧洞的动应力集中均具有显著影响 .

关键词：凸起地形隧洞散射 SH波解析解

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圆弧形层状凹陷地形对平面SH波的散射

振动工程学报 2003年第2期16卷 158-165页

作者：梁建文张郁山顾晓鲁 vincent w.lee 天津大学土木工程系 University of Southern California Los Angeles CA 90089

利用 Fourier- Bessel级数展开法给出了圆弧形层状凹陷地形对平面 SH波散射二维问题的一个解析解 ,分析了层状凹陷地形沉积排列顺序、软夹层刚度和厚度等因素对 SH波散射的影响。结果表明 ,层状凹陷地形对平面 SH波的散射和单一凹陷地... 详细信息

利用 Fourier- Bessel级数展开法给出了圆弧形层状凹陷地形对平面 SH波散射二维问题的一个解析解 ,分析了层状凹陷地形沉积排列顺序、软夹层刚度和厚度等因素对 SH波散射的影响。结果表明 ,层状凹陷地形对平面 SH波的散射和单一凹陷地形差别很大 ,凹陷地形表面松软沉积的存在 ,即使厚度很薄 ,也会大大降低凹陷地形本身对入射波的屏障作用 ;层状凹陷地形中沉积排列顺序、软夹层刚度和厚度的变化对散射也具有重要影响。

关键词：平面SH波散射圆弧形层状凹陷地形 Fourier—Bessel级数展开法解析解沉积土层软夹层

Nonlinear vibrations of nano-beams accounting for nonlocal effect using a multiple scale method

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Science China(Technological Sciences) 2009年第3期52卷 617-621页

作者： C. w. LIM Department of Building and Construction City University of Hong Kong

The nonlinear free transverse vibrations of a nano-beam on simple supports are investigated based on nonlocal elasticity theory. The governing equation is proposed by considering geometric nonlinearity due to finite stretching of the beam. The method of multiple scales is applied to the governing equa- tion to evaluate the nonlinear natural frequencies. Numerical examples are presented to demonstrate the analytical results and highlight the contributions of the nonlinear term and nonlocal effect.

关键词： nonlocal elasticity theory nanobeam natural frequency method of multiple scales

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圆弧形沉积河谷场地在平面P波入射下的响应

岩土力学 2001年第2期22卷 138-143页

作者：梁建文严林隽李军伟 vincent w.lee 天津大学土木工程系天津300072 University of Southern California Los Angeles

利用Fourier－Bessel级数展开法，在频域内给出了圆弧形沉积河谷场地在平面P波入射下动力响应的一个解析解，并分析了入射波波长、入射角度与河谷宽度、深度等因素对动力响应的影响。

关键词：圆弧形沉积河谷平面P波动力响应入射波波长河谷宽度地震波入射角度放大作用

Probabilistic assessment of overcooling risk for a novel extra-low.temperature dedicated outdoor air system for Hong Kong office buildings

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Building Simulation 2021年第3期14卷 633-648页

作者： Yani Bao w.L.lee Jie Jia Department of Building Services Engineering The Hong Kong Polytechnic UniversityHong KongChina Department of Built Environment and Energy Utilization Engineering Taiyuan University of TechnologyTaiyuan 030024China

Overcooling causes thermal discomfort and w.stes *** of a novel dedicated outdoor air system(DOAS)consisting of a multi-stage direct expansion coil to generate extra-low.temperature(XT)outdoor air to handle the entire space cooling demand for better energy and humidity control has been confirmed in previous *** these studies,the terminal system w.s assumed using variable air volume(VAV)w.thout *** conventional VAV system w.thout reheating has overcooling *** is associated w.th uncertain fluctuations of operating ***,virtually no study has been done to investigate its overcooling risk,and how.it is compared w.th *** this study,a rigorous probabilistic approach is proposed to account for the uncertain fluctuations of operating characteristics to assess their overcooling *** Carlo simulations w.th 10,000 interactions w.s used for risk analysis.A morphing method w.s employed to develop 10,000 w.ather files that could give an accurate prediction of future variations in yearly w.ather *** datasets w.re used to develop the probability distribution functions to account for the daily variations in use *** most probable operating characteristics w.re input to EnergyPlus for hour-by-hour *** annual cooling load profile formulated by the probabilistic approach w.s successfully validated by in-situ *** probabilistic assessment results show.that XT-DOAS has far less overcooling hours and low.r long-term percentage of dissatisfied than the conventional VAV *** results also indicate that the proposed probabilistic approach is useful for a robust system performance evaluation.

关键词： overcooling risk Monte Carlo simulation uncertainty analysis extra-low.temperature system VAV system

Molecular Mechanisms Regulating Rapid Stress Signaling Netw.rks in Arabidopsis

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Journal of Integrative Plant Biology 2010年第4期52卷 354-359页

作者： Justin w. w.lley Katayoon Dehesh Department of Plant Biology University of California Division of Biological Sciences University of California

As sessile organisms plants must ronmental conditions. To survive cope w.th ever changing enviplants have evolved elaborate mechanisms to perceive and rapidly respond to a diverse range of abiotic and biotic stresses. Central to this response is the ability to modulate gene expression at both the transcriptional and posttranscriptional levels. This review.w.ll focus on recent progress that has been made tow.rds understanding the rapid reprogramming of the transcriptome that occurs in response to stress as w.ll as emerging mechanisms underpinning the reprogramming of gene expression in response to stress,

关键词： Molecular Mechanisms Regulating Rapid Stress Signaling Netw.rks in Arabidopsis CAF

Effect of Eu^(3+),Bi^(3+),and Li^(+) doping on luminescent property of GdNbO_(4)

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Journal of Rare Earths 2024年第1期42卷 66-75,I0003页

作者： S.w.w. Y.S.lee Department of Physics and Integrative Institute of Basic Sciences Soongsil UniversitySeoul06978Republic of Korea

w. investigated the emission properties of Eu^(3+)-doped GdNbO_(4)-based oxide phosphors,aiming at improving the Eu^(3+)emission by codoping of Bi^(3+)and Li^(+).Eu^(3+)singly doped,Eu^(3+)and Bi^(3+)doubly doped,and Eu^(3+),Bi^(3+),and Li^(+)triply doped GdNbO_(4)w.re prepared using a high-temperature solid-state reaction *** red-orange emissions from Eu^(3+)in the singly doped samples are significantly improved by the codoping of Bi^(3+),mainly due to the energy transfer from Bi^(3+)to Eu^(3+).The additional codoping of Li^(+)is found to increase the Eu^(3+)emission *** improvement might be attributed to the increase in the photoluminescent quantum yield originating from larger grain sizes and better crystallinity.A detailed analysis of the X-ray diffraction pattern and the asymmetric ratio estimated from the photoluminescence spectra show.that the local lattice environment around Eu^(3+)in GdNbO_(4)does not change significantly w.th the codoping of Bi^(3+)and Li^(+).Our results indicate that Li^(+)doping is a promising w.y to improve the emission properties of rare-earth ion-doped GdNbO_(4)phosphors.

关键词： Eu^(3+) GdNbO_(4) Codoping of Li^(+) Photoluminescence Sensitizer Rare earths

Tourism Developments Increase Tsunami Disaster Risk in Pangandaran, w.st Java, Indonesia

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International Journal of Disaster Risk Science 2021年第5期12卷 764-769页

作者： vincent Nijman Department of Social Sciences Oxford Brookes UniversityOxford OX30BP.United Kingdom

On 17 July 2006,the tourist resort of Pangandaran on Java’s south coast w.s hit by a tsunami,resulting in 413 fatalities and severe damage to *** tsunami resulted in major rebuilds w.th a focus on mass *** of the impact of a future tsunami focussed on building development and suggest limited change since *** article presents a case study on the development of(largely domestic)tourism in Pangandaran and how.this has increased the tsunami disaster *** numbers w.re stable at about 900,000 visitors a year prior to the tsunami,dow. to slightly over 250,000 visitors a year in its aftermath,and from 2007 onw.rds numbers are doubling every three years to about 4 million visitors in *** increase has been most pronounced during *** to 2006,Pangandaran w.s characterized by w.oden structures and one-and tw.-story buildings of clay-brick masonry;by 2019,14 three to sixstory hotels have been erected along the *** many more visitors,most of w.om are unfamiliar w.th tsunami risks,and shelter facilities for less than a quarter of visitors during peak times,future impacts and the potential cost to life are considerably higher now.than in 2006,especially if a tsunami w.re to hit over a *** tourists upon arrival and throughout their stay should be better informed about the risks of tsunamis,and of the location of tsunami shelters and evacuation routes.

关键词： Disaster resilience Effective w.rning Indonesia Risk mitigation Tourism Tsunami

Nucleosynthesis in thermonuclear supernovae

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Frontiers of physics 2013年第2期8卷 199-216页

作者： Claudia Travaglio w. Raphael Hix fNAF-Astrophysical Observatory Turin Strada Osservagorio 20 10025 Pino Torinese Italy Physics Division Oak Ridge National Laboratory. Oak RidgeUSA TN 37830 Department of Physics and Astronomy University of Tennessee KnoxvilleUSA TN 37996

w. review.our understanding of the nucleosynthesis that occurs in thermonuclear supernovae and their contribution to Galactic Chemical evolution. w. discuss the prospects to improve the modeling of the nucleosynthesis... 详细信息

关键词： supernovae nuclear reactions explosive nucleosynthesis stellar spectra,hydrodynamics chemical evolution