检索结果-南通市图书馆

MODEL ANALYSIS AND PARAMETER EXTRACTION FOR MOS CAPACITOR INCLUDING QUANTUM MECHANICAL EFFECTS

在线全文

学校读者我要写书评

暂无评论

Journal of Computational Mathematics 2006年第3期24卷 401-411页

作者： Hai-yan Jiang ping-wen Zhang LMAM CCSE and School of Mathematical Sciences.Peking University Beijing 100871 China

The high frequency CV curves of MOS capacitor have been studied. It is shown that semiclassical model is a good approximation to quantum model and approaches to classical model when the oxide layer is thick. This conclusion provides us an efficient （semiclassical） model including quantum mechanical effects to do parameter extraction for ultrathin oxide device. Here the effective extracting strategy is designed and numerical experiments demonstrate the validity of the strategy.

关键词： Poisson Equation SchrSdinger Equation MOS Capacitor Quantum Effect,Sensitivity Parameter Extraction.

STABILITY OF THEORETICAL SOLUTION AND NUMERICAL SOLUTION OF NONLINEAR DIFFERENTIAL EQUATIONS WITH PIECEWISE DELAYS

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Computational Mathematics 2005年第4期23卷 393-400页

作者： Li-ping wen Shou-fu Li School of Mathematics and Computational Science Xiangtan University Xiangtan 411105 China

This paper is concerned with the stability of theoretical solution and numerical solution of a class of nonlinear differential equations with piecewise delays. At first, a sufficient condition for the stability of theoretical solution of these problems is given, then numerical stability and asymptotical stability are discussed for a class of multistep methods when applied to these problems.

关键词： Stability Delay differential equations Linear multistep methods

Comparison between the Response of the Northwest Pacific Ocean and the South China Sea to Typhoon Megi(2010)

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Advances in Atmospheric Sciences 2017年第1期34卷 79-87页

作者： Zi-Liang LI ping wen Physical Oceanography Laboratory College of Oceanic and Atmospheric SciencesOcean University of ChinaQingdao 266100China Hunan Provincial Meteorological Station Changsha 430100China

The upper-ocean responses to Typhoon Megi （2010） are investigated using data from ARGO floats and the satellite TMI. The experiments are conducted using a three-dimensional Princeton Ocean Model （POM） to assess the storm, which affected the Northwest Pacific Ocean （NWP） and the South China Sea （SCS）. Results show that the upwelling and entrainment experiment together account for 93% of the SST anomalies, where typhoon-induced upwelling may cause strong ocean cooling. In addition, the anomalous SST cooling is stronger in the SCS than in the NWP. The most striking feature of the ocean response is the presence of a two-layer inertial wave in the SCS--a feature that is absent in the NWE The near-inertial oscillations can be generated as typhoon wakes, which have maximum flow velocity in the surface mixed layer and may last for a few days, after the typhoon＇s passage. Along the typhoon tracks, the horizontal currents in the upper ocean show a series of alternating negative and positive anomalies emanating from the typhoon.

关键词： typhoon South China Sea Northwest Pacific upwelling entrainment near-inertial oscillation

Transient accelerating scalar models with exponential potentials

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2013年第6期13卷 629-634页

作者： wen-ping Cui Yang Zhang Zheng-wen Fu Key Laboratory for Research in Galaxies and Cosmology The University of Science and Technology of China Chinese Academy of Sciences

We study a known class of scalar dark energy models in which the potential has an exponential term and the current accelerating era is transient. We find that, although a decelerating era will return in the future, when extrapolating the model back to earlier stages （z ≥ 4）, scalar dark energy becomes dominant over matter. So these models do not have the desired tracking behavior, and the predicted transient period of acceleration cannot be adopted into the standard scenario of the Big Bang cosmology. When couplings between the scalar field and matter are introduced, the models still have the same problem; only the time when deceleration returns will be varied. To achieve re-deceleration, one has to turn to alternative models that are consistent with the standard Big Bang scenario.

关键词： cosmology cosmological parameters -- cosmology theory

Orientation-Dependent Morphology and Evolution of Interfacial Dislocation Networks in Ni-Based Single-Crystal Superalloys:A Molecular Dynamics Simulation

在线全文

学校读者我要写书评

暂无评论

Acta Mechanica Solida Sinica 2021年第1期34卷 79-90页

作者： Bin Chen wen-ping Wu Ming-Xiang Chen Department of Engineering Mechanics School of Civil EngineeringWuhan UniversityWuhan430072China State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan430072China

In this paper,the morphology and evolution of interfacial dislocation networks of(100),(110)and(111)interphases of Ni-based single-crystal superalloys are studied by molecular dynamics(MD)***-dimensional cubic-type and sandwich-type models are chosen to explore the orientation-dependent morphology of dislocation networks,and their respective advantages and disadvantages are *** the simulations,it is observed that various lattice orientations and model types lead to different morphologies of dislocation *** on the analysis of average atomic energy and dislocation characteristics,the(100)orientation model has a more regular dislocation network,lower energy and better stability than the(110)and(111)orientation models after MD relaxation,which are supported by previous experimental and numerical ***,the cubic-type model has lower energy and better stability than the sandwich-type *** will be helpful for choosing a more appropriate and reasonable model for simulating the interfacial dislocation networks of Ni-based single-crystal superalloys.

关键词： Ni-based single-crystal superalloys Molecular dynamics simulation Orientation Interfacial dislocation networks

Assessment of Soil Water Content in Field with Antecedent Precipitation Index and Groundwater Depth in the Yangtze River Estuary

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2013年第4期12卷 711-722页

作者： XIE wen-ping YANG Jing-song State Key Laboratory of Soil and Sustainable Agriculture/Institute of Soil Science Chinese Academy of Sciences

To better understand soil moisture dynamics in the Yangtze River Estuary （YRE） and predict its variation in a simple way, a field monitoring experiment was carried out along the north branch of the Yangtze River, where seawater intrusion was strong and salt-water variation is one of the limiting factors of local agriculture. In present paper, relation between antecedent precipitation index （API） and soil water content is studied, and effects of groundwater depth on soil water content was analyzed. A relatively accurate prediction result of soil water content was reached using a neural network model. The impact analysis result showed that the variation of the API was consistent with soil water content and it displayed significant correlations with soil water content in both 20 and 50 cm soil layer, and higher correlation was observed in the layer of 20 cm. Groundwater impact analysis suggested that soil moisture was affected by the depth of groundwater, and was affected more greatly by groundwater at depth of 50 cm than that at 20 cm layer. By introducing API, groundwater depth and temperature together, a BP artificial network model was established to predict soil water content and an acceptable agreement was achieved. The model can be used for supplementing monitoring data of soil water content and predicting soil water content in shallow groundwater areas, and can provide favorable support for the research of water and salt transport in estuary area.

关键词： antecedent precipitation index groundwater depth soil water content assessment

Excess heat capacity in glass-forming liquid systems containing molecules

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2013年第6期56卷 1090-1095页

作者： KE HaiBo wen ping WANG WeiHua Institute of Physics Chinese Academy of Sciences

Excess heat capacities at glass transition temperature in two types of glass-forming systems of [xNaNO3(1x)KNO3]60·[Ca(NO3)2]40(0x1) and Ca(NO3)2yH2O(4y13) are *** the former system,with the replacement of K + cation with Na + cation,the excess heat capacity is around 65.1 J mol-1·K-1,while the excess increases by 38.9 J mol-1·K-1 upon one molar H2O content in latter system.A quantitative description to the excess heat capacity is built up with the thermal effects of atomic and molecular translational motion in *** results might offer a further understanding to the glass transition.

关键词： glass-forming liquid excess heat capacity the glass transition

On the Finite Convergence of Newton-type Methods for P_0 Affine Variational Inequalities

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2007年第9期23卷 1553-1562页

作者： Li ping ZHANG wen Xun XING Department of Mathematical Sciences Tsinghua University Beijing 100084 P. R. China

Based on the techniques used in non-smooth Newton methods and regularized smoothing Newton methods, a Newton-type algorithm is proposed for solving the P0 affine variational inequality problem. Under mild conditions, the algorithm can find an exact solution of the P0 affine variational inequality problem in finite steps. Preliminary numerical results indicate that the algorithm is promising.

关键词： affine variational inequality non-smooth smoothing Newton method finite termination

Regulated polarization degree of upconversion luminescence and multiple anti-counterfeit applications

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第5期43卷 2172-2183页

作者： Dong-ping wen ping Chen Yi Liang Xiao-Ming Mo Cao-Feng Pan Center On Nanoenergy Research Guangxi Key Laboratory for Relativistic AstrophysicsSchool of Physical Science and TechnologyGuangxi UniversityNanning 530004China Key Laboratory of Micronano Energy and Sensor CAS Center for Excellence in NanoscienceBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing 100140China

Polarization upconversion luminescence(PUCL)of lanthanide ions(Ln^(3+))has been widely used in single particle tracking,microfluidics detection,three-dimensional displays,and so ***,no effective strategy has been developed for modulating *** we report a strategy to regulate PUCL in Ho^(3+)-doped NaYF4single nanorods based on the number of upconversion *** constructing a multiphoton upconversion system for Ho^(3+),we regulate the degree of polarization(DOP)of PUCL from 0.590 for two-photon luminescence to 0.929 for three-photon upconversion luminescence(UCL).Furthermore,our strategy is verified from cross-relaxation between Ho^(3+)and Yb^(3+),excitation wavelength,excitation power density,and local site *** this regulation strategy of PUCL has also been achieved in Tm^(3+),with the DOP ranging from 0.233 for two-photon luminescence to 0.925 for four-photon UCL Besides,multi-dimensional anti-counterfeiting display has been explored with *** work provides an effective strategy for regulating PUCL and also provides more opportunities for the development of polarization display optical encoding,anti-counterfeiting,and integrated optical devices.

关键词： Polarization upconversion luminescence Degree of polarization Population density of excited state Number of upconversion photons Polarization anti-counterfeitingdisplay