检索结果-南通市图书馆

ON THE VALIDITY OF THE LOCAL FOURIER ANALYSIS

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 2019年第3期37卷 340-348页

作者： Carmen Rodrigo Francisco j.gaspar Ludmil T.Zikatanov Departamento de Matematica Aplicada IUMAUniversidad de ZaragozaZaragozaSpain CWI Centrum Wiskunde & InformaticaScience Park 1231090 AmsterdamThe Netherlands Department of Mathematics The Pennsylvania State UniversityUniversity ParkPennsylvania 16802USAInstitute for Mathematics and InformaticsBulgarian Academy of SciencesSofia.Bulgaria

Local Fourier analysis(LFA)is a useful tool in predicting the convergence factors of geometric multigrid methods(GMG).As is well known,on rectangular domains with periodic boundary conditions this analysis gives the exact convergence factors of such met *** other boundary conditions are considered,however,this analysis was judged as been heuristic,with limited capabilities in predicting multigrid convergence *** this work,using the Fourier method,we extend these results by proving that such analysis yields the exact convergence factors for a wider class of problems,some of which can not be handled by the traditional rigorous Fourier analysis.

关键词： Local Fourier analysis Multigrid Fourier method

Measurement of in-plane deformations of microsystems by digital holography and speckle interferometry(Invited Paper)

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

Chinese Optics Letters 2009年第12期7卷 1109-1112页

作者： G. Pedrini j. gaspar O. Paul W. Osten Institut fr Technische Optik Universitt Stuttgart Department of Microsystems Engineering-IMTEK Universitt Freiburg

The reliability of microsystems is an important issue and for their quality inspection, it is necessary to know the displacements or deformations due to the applied mechanical, thermal, or electrostatic loads. We show how interferometrical techniques like digital holography and speckle interferometry can be used for the measurement of in plane deformations of microsystems with nanometric accuracy and we give a description of the measurement uncertainties.

关键词： Invited Paper Measurement of in-plane deformations of microsystems by digital holography and speckle interferometry

维普期刊数据库

A Posteriori Stabilized Sixth-Order Finite Volume Scheme with Adaptive Stencil Construction:Basics for the 1D Steady-State Hyperbolic Equations

在线全文

学校读者我要写书评

暂无评论

Communications on Applied Mathematics and Computation 2023年第2期5卷 751-775页

作者： gaspar j.machad. Stéphane Clain Raphaël Loubère Centre of Physics and Department of Mathematics University of MinhoCampus of Azurém4800-058 GuimaraesPortugal CNRS and Institut de Mathématiques de Bordeaux(IMB) Universitéde BordeauxTalenceFrance

We propose an adaptive stencil construction for high-order accurate finite volume schemes a posteriori stabilized devoted to solve one-dimensional steady-state hyperbolic *** accuracy(up to the sixth-order presently)is achieved,thanks to polynomial recon-structions while stability is provided with an a posteriori MOOD method which controls the cell polynomial degree for eliminating non-physical oscillations in the vicinity of *** supplemented this scheme with a stencil construction allowing to reduce even further the numerical *** stencil is shifted away from troubles(shocks,discontinuities,etc.)leading to less oscillating polynomial *** on linear,Burgers',and Euler equations,we demonstrate that the adaptive stencil technique manages to retrieve smooth solutions with optimal order of accuracy but also irregular ones without spurious ***,we numerically show that the approach allows to reduce the dissipation still maintaining the essentially non-oscillatory behavior.

关键词： Finite volume MOOD Adaptive stencil Steady-state solution Euler equations High order

Finite element model with imposed slip surfaces for earth mass safety evaluation

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 Central South University 2014年第9期21卷 3627-3638页

作者： Nuno ARAUjO gaspar j.machad. julio B.MARTINS Hugo M.R.D.SILVA C-TAC Territory Environment and Construction Research Centre School of EngineeringUniversity of Minho Guimaraes 4800-058 Portugal Centre of Mathematics School of Sciences University of Minho Guimaraes 4800-058 Portugal

The study of earth masses requires numerical methods that provide the quantification of the safety factor without requiring detrimental assumptions. For that, equilibrium analysis can perform fast computations but require assumptions that limit its potentiality. Limit analysis does not require detrimental assumptions but are numerically demanding. This work provides a new approach that combines the advantage of both the equilibrium method and the limit analysis. The defined hybrid model allows probabilistic analysis and optimization approaches without the assumption of interslice forces. It is compared with a published case and used to perform probabilistic studies in both a homogeneous and a layered foundation. Analyses show that the shape of the density probability functions is highly relevant when computing the probability of failure, and soil elasticity hardly affects the safety of factor of the earth mass.

关键词： slope stability probabilistic methods reliability genetic algorithms safety factor

维普期刊数据库

Redistribution of Soil Organic Carbon Triggered by Erosion at Field Scale Under Subhumid Climate,Hungary

在线全文

学校读者我要写书评

暂无评论

Pedosphere 2016年第5期26卷 652-665页

作者： Zoltan SZALAI judit SZABO jozsef KOVACS Erzsebet MESZAROS gaspar ALBERT Csaba CENTERI Boglarka SZABO Balazs MADARASZ Dora ZACHARY Gergely jAKAB Geographical Institute Research Centre for Astronomy and Earth Sciences Hungarian Academy of SciencesBudapest 1112(Hungary) Department of Environmental and Landscape Geography Eotvos Lordnd UniversityBudapest 1117(Hungary) Department of Applied and Environmental Geology Eotvos Lordnd UniversityBudapest 1117(Hungary) Department of Cartography and Geoinformatics Eotvos Lordnd UniversityBudapest 1117(Hungary) Department of Nature Conservation and Landscape Ecology Szent Istvdn UniversityGodollo 2100(Hungary)

Soil organic carbon(SOC) has primary importance in terms of soil physics, soil fertility and even of climate change control. One hundred soil samples were taken from an intensively cultivated Cambisol to quantify SOC redistribution triggered by soil erosion under a subhumid climate, by the simultaneous application of diffuse reflectance(240–1 900 nm) and traditional physico-chemical *** representative sample points were collected from the solum along the slopes at the depth of 20–300 cm with a mean SOC content of 12 g kg^(-1). Hierarchical cluster analyses were performed based on the determined SOC results. The spatial pattern of the groups created were similar, and even though the classifications were not the same, diffuse reflectance had proven to be a suitable method for soil/sediment classification even within a given arable field. Both organic and inorganic carbon distributions were found to be a proper tool for estimations of past soil erosion processes. The SOC enrichment was found on two sedimentary spots with different geomorphological positions. Soil organic matter composition also differed between the two spots due to selective deposition of the delivered organic matter. The components with low-molecular-weight reached the bottom of the slope where they could leach into the profile, while the more polymerised organic matter compositions were delivered and deposited even before on a higher segment of the slope in an aggregated form. This spatial difference appeared below the uppermost tilled soil layer as well, referring the lower efficiency of conventional ploughing tillage in soil spatial homogenisation.

关键词： Cambisol carbon sequestration diffuse reflectance selective erosion soil organic matter composition

维普期刊数据库

Calibration of Optical Systems for the Measurement of Microcomponents

在线全文

学校读者我要写书评

暂无评论

Calibration of Optical Systems for the Measurement of Microc...

International Conference on Experimental Mechanics 2008 (ICEM 2008)

作者： W.Osten G.Pedrini O.Paul j.gaspar Institute for Technical Optics University of Stuttgart

＜正＞Optical coherent techniques are well suited for the measurement of quantitative data of micro components but give only accurate results when calibrated systems are *** paper presents a strategy for the calibrati...

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

用四唑分析小麦种子不需将胚切开的新方法

种子 1986年第1期 66-67页

作者： gaspar S Nagy j 贺仲铭

我们使用不切开胚的方法鉴定了20个小麦样品的生活力。种子在浸水后放入四唑溶液中,用频率22KH,强度0.69瓦/厘米~2的超声波处理5～10分钟。超声波的处理促进了药液透入吸湿的种子。在20℃下染色24小时后,种子在乳酚(lactophenol)中煮沸... 详细信息

我们使用不切开胚的方法鉴定了20个小麦样品的生活力。种子在浸水后放入四唑溶液中,用频率22KH,强度0.69瓦/厘米~2的超声波处理5～10分钟。超声波的处理促进了药液透入吸湿的种子。在20℃下染色24小时后,种子在乳酚(lactophenol)中煮沸至种皮透明,不需将胚切开,能透过种皮鉴定胚的生活力。

关键词：小麦种子生活力超声波处理发芽力种皮四唑四氮杂茂氮杂环化合物

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

用C++开发Web商用程序

丛书名：计算机软件开发与程序设计系列丛书

1998年

作者：（美）（D.加斯帕）Don gaspar 杨晓云王建桥译

互连网络-C语言-程序设计 C语言-互连网络-程序设计程序设计-C语言-互连网络

ISBN: (数字)7111063236

ISBN: (纸本)7111063236

互连网络-C语言-程序设计 C语言-互连网络-程序设计程序设计-C语言-互连网络

关键词：互连网络 C语言程序设计

来源：畅想之星图书光盘版（南... 评论

在线全文

畅想之星图书光盘版（南通市图书馆镜像）

学校读者我要写书评

暂无评论

温带湿润气候条件下温室的能量平衡

气象科技 1988年第6期 64-70页

作者： H.j.Levit R.gaspar 王学文

一个模拟多种不同气候条件下的温室微气候状况的计算机动态模式业已建立并得到了验证。该模式是一维的,由四个层次组成,对各层的热量和质量通量进行了模拟。模式只需要输入初始边界条件。叶片的水分扩散由影响气孔阻力的环境参数来确定... 详细信息

一个模拟多种不同气候条件下的温室微气候状况的计算机动态模式业已建立并得到了验证。该模式是一维的,由四个层次组成,对各层的热量和质量通量进行了模拟。模式只需要输入初始边界条件。叶片的水分扩散由影响气孔阻力的环境参数来确定。除以往模式中的考虑外,还考虑了作物热贮量和作物特征的时间演变。分析了模式对各种参数的敏感性。用当地的一个商业温室获得观测实际资料,并将其与模拟值进行对照,两组资料十分一致。还用这个计算机动态模式计算了用于种植草莓的温室所需能量的大小。

关键词：模拟值实测值作物贮量加热器能量平衡