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Multiscale Basis Functions for Singular Perturbation on Adaptively Graded Meshes

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Advances in Applied Mathematics and Mechanics 2014年第5期6卷 604-614页

作者： Mei-Ling Sun Shan Jiang College of Mathematics Science Yangzhou UniversityYangzhou 225002China Education and Technology Center Nantong Vocational CollegeNantong 226007China Department of Mathematics Texas A&M UniversityCollege StationTX 77843USA

We apply the multiscale basis functions for the singularly perturbed reaction-diffusion problem on adaptively graded meshes,which can provide a good balance between the numerical accuracy and computational *** multiscale space is built through standard finite element basis functions enriched with multiscale basis *** multiscale basis functions have abilities to capture originally perturbed information in the local problem,as a result our method is capable of reducing the boundary layer errors remarkably on graded meshes,where the layer-adapted meshes are generated by a given *** numerical experiments we demonstrate that the multiscale method can acquire second order convergence in the L^(2)norm and first order convergence in the energy norm on graded meshes,which is independent ofε.In contrast with the conventional methods,our method is much more accurate and effective.

关键词： Multiscale basis functions singular perturbation boundary layer adaptively graded meshes.

One Nonparabolic End Theorem on Kahler Manifolds

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Communications in Mathematical Research 2014年第3期30卷 237-244页

作者： ZHU PENG Yin Jing-xue School of Mathematics and Physics Jiangsu University of Technology

In this paper, the complete noncompact Kahler manifolds satisfying the weighted Poincare inequality are considered and one nonparabolic end theorem which generalizes Munteanu＇s result is obtained.

关键词： nonparabolic end weighted Poincare inequality Kahler manifold

Effects of flashing green on driver's stop/go decision at signalized intersection

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Journal of Central South university 2015年第2期22卷 771-778页

作者：沈家军王炜 College of Civil Science and Engineering Yangzhou University School of Transportation Southeast University

The primary objective of this work is to explore how drivers react to flashing green at signalized intersections. Through video taping and data procession based on photogrammetry, the operating speeds of vehicles before and after the moment when flashing green started was compared using paired-samples T-test. The critical distances between go and stop decisions was defined through cumulative percentage curve. The boundary of dilemma zone was determined by comparing stop distance and travel ***-running violation was analyzed on the basis of the travel time to the stop line. And finally, a logistic model for stop and go decisions was constructed. The results shows that the stopping ratios of the first vehicles of west-bound and east-bound approaches are 41.3% and 39.8%, respectively; the amber-light running violation ratios of two approaches are 31.6% and 25.4%, respectively;the operating speed growth ratios of first vehicles selecting to cross intersection after the moment when flashing green started are26.7% and 17.7%, respectively; and the critical distances are 48 m and 46 m, respectively, which are close to 44 m, the boundary of dilemma zone. The developed decision models demonstrate that the probability of go decision is higher when the distance from the stop line is shorter or operating speed is higher. This indicates that flashing green is an effective way to enhance intersection safety,but it should work together with a strict enforcement. In addition, traffic signs near critical distance and reasonable speed limitation are also beneficial to the safety of intersections.

关键词： signalized intersections flashing green critical distance dilemma zone amber-running violation logistic decision model

Recent advances in nanotherapeutics for the treatment and prevention of acute kidney injury

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Asian Journal of Pharmaceutical Sciences 2021年第4期16卷 432-443页

作者： Hui Yu Di Liu Gaofeng Shu Feiyang Jin Yongzhong Du Institute of Pharmaceutics College of Pharmaceutical SciencesZhejiang UniversityHangzhou 310058China

Acute kidney injury(AKI)is a serious kidney disease without specific medications currently except for expensive dialysis *** potential drugs are limited due to their high hydrophobicity,poor in vivo stability,low bioavailability and possible adverse ***,kidney-targeted drugs are not common and small molecules are cleared too quickly to achieve effective drug concentrations in injured *** problems limit the development of pharmacological therapy for *** based on nanotechnology have been proved to be an emerging and promising treatment strategy for AKI,which may solve the pharmacological therapy *** and more nanotherapeutics with different physicochemical properties are developed to efficiently deliver drugs,increase accumulation and control release of drugs in injury kidneys and also directly as effective ***,we discuss the recent nanotherapeutics applied in the treatment and prevention of AKI with improved effectiveness and few side effects.

关键词： Nanotherapeutic Acute kidney injury Drug delivery Target Controlled release Inorganic nanoparticles

A novel latch-up free SCR-LDMOS with high holding voltage for a power-rail ESD clamp

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Journal of Semiconductors 2013年第1期34卷 53-57页

作者：潘红伟刘斯扬孙伟锋 National ASIC System Engineering Research Center Southeast University

The low snapback holding voltage of the SCR-LDMOS device makes it susceptible to latch-up failure,when used in power-rail ESD（electro-static discharge） clamp *** order to eliminate latch-up risk,this work presents a novel SCR-LDMOS structure with an N-type implantation layer to achieve a 17 V holding voltage and a 5.2 A second breakdown *** device has been validated using TLP measurement analysis and is applied to a power-rail ESD clamp in half-bridge driver ICs.

关键词： ESD protection ESD robustness SCR-LDMOS latch-up holding voltage

Stress analysis of anisotropic thick laminates in cylindrical bending using a semi-analytical approach

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Journal of Zhejiang university-Science A(Applied Physics & Engineering) 2007年第11期8卷 1740-1745页

作者： LU Chao-feng LIM C.W. XU Feng Department of Civil Engineering Zhejiang University Hangzhou 310027 China） Department of Building and Construction City University of Hong Kong Kowloon Hong Kong China Zhejiang Tiandi Environmental Protection Engineering Co. Ltd. Hangzhou 310012 China

Semi-analytical elasticity solutions for bending of angle-ply laminates in cylindrical bending are presented using the state-space-based differential quadrature method (SSDQM). Partial differential state equation is derived from the basic equations of elasticity based on the state space concept. Then, the differential quadrature (DQ) technique is introduced to discretize the longitu- dinal domain of the plate so that a series of ordinary differential state equations are obtained at the discrete points. Meanwhile, the edge constrained conditions are handled directly using the stress and displacement components without the Saint-Venant principle. The thickness domain is solved analytically based on the state space formalism along with the continuity conditions at interfaces. The present method is validated by comparing the results to the exact solutions of Pagano’s problem. Numerical results for fully clamped thick laminates are presented, and the influences of ply angle on stress distributions are discussed.

关键词： Semi-analytical elasticity solution State-space-based differential quadrature method (SSDQM) Angle-ply laminates Cylindrical bending

Nondoped-type White Organic Light-Emitting Diode Using Star-Shaped Hexafluorenylbenzene as an Energy Transfer Layer

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Chinese Journal of Chemical Physics 2008年第5期21卷 500-504页

作者： Jun-sheng Yu Tao Ma Shuang-ling Lou Ya-dong Jiang Qing Zhang State Key Laboratory of Electronic Thin Films and Integrated Devices School of Optoelectronic Information University of Electronic Science and Technology of China Chengdu 510054 China Department of Polymer Science School of Chemistry and Chemical Technology Shanghai Jiao Tong University Shanghai 200240 China

White organic light-emitting diodes （WOLEDs） with a structure of indium-tin-oxide （ITO）/N,N＇-bis- （1-naphthyl）-N,N＇-diphenyl- （1, 1＇-biphenyl）-4,4＇-diamine （NPB）/1,2,3,4,5,6-hexakis（9,9-diethyl-9H-fluoren-2- yl）benzene （HKEthFLYPh）/5,6,11,12-tetraphenylnaphtacene （rubrene）/tris（8-hydroxyquinoline） aluminum （Alq3）/Mg：Ag were fabricated by vacuum deposition method, in which a novel star-shaped hexafluorenyl- benzene HKEthFLYPh was used as an energy transfer layer, and an ultrathin layer of rubrene was inserted between HKEthFLYPh and Alq3 layers as a yellow light-emitting layer instead of using a time-consuming doping process. A fairly pure WOLED with Commissions Internationale De L＇Eclairage （CIE） coordinates of （0.32, 0.33） was obtained when the thickness of rubrene was 0.3 nm, and the spectrum was insensitive to the applied voltage. The device yielded a maximum luminance of 4816 cd/m2 at 18 V.

关键词： White organic light-emitting diode diethyl-9H-fluoren-2-yl)benzene Energy transfer Star-shaped hexafluorenylbenzene 1 2 3 4 5 6-hexakis(9 9- Ultrathin layer

Relationship between rheological manufacturing process and optical performance of optical fiber coupler

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Journal of Central South university of Technology 2006年第2期13卷 175-179页

作者：帅词俊段吉安钟掘 School of Mechanical and Electrical Engineering Central South University Changsha 410083China

Through theoretical analysis and experiments, the viscoelastic mechanical model of optical fiber coupler in the process of fused biconical taper was established, and the numerical analysis in non-uniform temperature field was made. The results show that the rheological parameters, such as drawing speed and fused temperature, have a tremendous influence on stress distribution and performance of optical fiber coupler, especially the influence of fused temperature. The change of fused temperature by 5℃ can lead to the change of the maximum stress by 30% and stress difference by 20% in the same cross section. The change of temperature gradient by 3% can result in the change of stress difference by 90%. In the present condition of rheological technology, rheological defects such as crystallizations and microcracks are easy to generate in the optical fiber coupler.

关键词： optical fiber coupler fused biconical taper viscoelastic rheology

Simulation of mold filling and prediction of gas entrapment on practical high pressure die castings

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Transactions of Nonferrous Metals Society of China 2010年第11期20卷 2064-2070页

作者：赵海东白砚飞欧阳晓贤董普云 State Engineering Research Center for Metallic Materials Net-shape Forming South China University of Technology

Element parameters including volume filled ratio,surface dimensionless distance,and surface filled ratio for DFDM(direct finite difference method)were proposed to describe shape and location of free surfaces in casting mold filling processes.A mathematical model of the filling process was proposed specially considering the mass,momentum and heat transfer in the vicinity of free ***,a method for gas entrapment was established by tracking flow of entrapped *** model and method were applied to practical ADC1 high pressure die *** gas entrapment prediction was compared with the fraction and maximum size of porosities in the different casting *** comparison shows validity of the proposed model and *** study indicates that final porosities in high pressure die castings are dependent on both gas entrapment during mold filling process and pressure transfer within solidification period.

关键词： high pressure die casting mold filling gas entrapment