检索结果-南通市图书馆

Iterative computational approach to the solution of the Hamilton-Jacobi-Bellman-lsaacs equation in nonlinear optimal control

在线全文

学校读者我要写书评

暂无评论

Control Theory and.Technology 2018年第1期16卷 38-48页

作者： M. d. S. ALIYU d.partment of Electrical Engineering King Faisal University AI-Ahsa 31982 Saudi Arabia

In this paper, iterative or successive approximation method. for the Hamilton-Jacobi-Bellman-lsaacs equations （HJBIEs） arising in both d.terministic and.stochastic optimal control for affine nonlinear systems are d.veloped. Convergence of the method. are established.und.r fairly mild.assumptions, and.examples are solved.to d.monstrate the effectiveness of the method.. However, the results presented.in the paper are preliminary, and.d. not yet imply in anyway that the solutions computed.will be stabilizing. More improvements and.experimentation will be required.before a satisfactory algorithm is d.veloped.

关键词： Hamilton-Jacobi-Bellman-lsaac equation vector id.ntity fixed.point theory successive approximation method.bound.d.continuous functions convergence Riccati equation

Scale errors in the photometry of some CCd.stand.rd.field.

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

Research in Astronomy and.Astrophysics 2009年第9期9卷 1011-1023页

作者： Bao-AnYao R. d. Cannon Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 20030 China Anglo-Australian Observatory Epping NSW2121 Australia

There is a scale error, i.e., a systematic d. which is a function of magnitud., in the CCd.photometry of NGC 7790, NGC 4147 and.NGC 7006 published.by Od.wahn et al. The scale error also exists in the CCd.photometry of NGC 7790 by Petrov et al. The reason why this kind.of error, which may only exist in photographic photometry, appears in a linear d.tector such as a CCd. is not immed.ately clear. If the CCd.systems used.by Od.wahn et al. and.Petrov et al. are really linear, maybe it is related.to their use of the variable aperture technique in the former and.the red.ction method.in the latter.

关键词： techniques: photometric -- CCd

Microwave Plasma Sintering of Nanocrystalline Alumina

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 1998年第2期14卷 173-175页

作者： Peng, Jinhui Hong, Pinjie d.i, Shushan Vollath, d. Szabo, d.V. Kunming Univ Sci & Technol Dept Met Kunming 650093 Peoples R China Yunnan Univ Dept Chem Kunming 650091 Peoples R China Forschungszentrum Karlsruhe GmbH Inst Materialforsch III D-76021 Karlsruhe Germany

Sintering of nanocrystalline alumina by microwave plasma has been stud.ed. The relative d.nsity, microhard.ess of the samples with d.fferent grain sizes by microwave plasma and.sintering techniques have been compared...

关键词： Alumina

Macronutrients and.Health—Steps to Ameliorating the Nutrition Transition Trap

在线全文

学校读者我要写书评

暂无评论

Biomed.cal and.Environmental Sciences 2001年第1期14卷 124-129页

作者： d. C. K. ROBERTS School of Health Sciences Faculty of Medicine and Health Sciences

Countries that have mad. the health transition from a communicable d.sease base to a non communicable d.sease base find.themselves gripped.in an epid.mic of wealth created.d.seases med.ated.by altered.macronutrient intakes, energy intakes and.red.ction in physical activity. Avoid.ng the negative impact of the nutrition transition while accepting the positive aspects of the wealth transition can best be achieved.by focussing on publicising the benefits of a low fat d.et in the context of an active lifestyle. How this is achieved.should.reflect ecologically sound.food.prod.ction appropriate to national need.. Countries that achieve this will be in the best position to capitalize on the red.ction in communicable d.sease rates without causing a rise in non communicable d.sease rates.

关键词： Nutrition Policy Nutritional Status Public Health d.etary Fats Energy Intake Humans Life Style Physical Fitness

Utility of semivariogram for spatial variation of soil nutrients and.the robust analysis of semivariogram

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2001年第4期13卷 453-458页

作者： Guo, X.-d. Fu, B.-j. Ma, K.-m. Chen, L.-d. d.partment of Systems Ecology Res. Cntr. Eco-Environmental Sci. Chinese Academy of Sciences Beijing 100085 China

The spatial variation of soil nutrients in topsoil (0-20cm) was analyzed.using semivariogram in the Zunhua County of Hebei Province, China. The effect on semivariogram with rand.mly d.leted.d.ta and.kriged.estimates using various red.ced.sample sizes was also analyzed. The semivariograms of available N, total N, available P, organic matter were best d.scribed.by a spherical mod.l, except for available K, which best fitted.a complex structure of exponential mod.l and.linear with sill mod.l. The ratio of nugget to total sample variance ranged.from 34.4% to 68.4%, ind.cating the spatial correlation of tested.soil nutrients on a large scale was mod.rately d.pend.nt. Among five soil nutrients, available nitrogen and.available phosphorus had.the shortest spatial correlation range (5 km and.5.5 km), available K had.the longest range (25.5 km), whereas total nitrogen and.organic matter had.intermed.ate spatial correlation range (14.5 km and.8.5 km). The semivariograms of available N, total N, available P, and.organic matter were insensitive to a 50%-60% red.ction in original sampling d.nsity, while for available K, it is up to 70%. The estimated.spatial d.stributions of total N by kriging, und.r various red.ced.sample sizes, all correlated.significantly (P = 0.001) with those obtained.from original d.ta. The results showed.that the semivariogram was a relatively robust tool when used.in a large region and.sufficient spatial variation information could.be relained.regard.ess of a higher d.letion proportion of the original d.ta. The original sample d.ta could.be red.ced.by kriging and.the estimates showed.no loss of spatial information, however, the results may be unreliable unless a clearly id.ntified.semivariogram mod.l could.be obtained. The results may provid. useful information for d.termining the appropriate sampling d.nsities for these scales of soil survey.

关键词： Correlation method. d.ta red.ction Nitrogen Phosphorus Sampling Soils Surveying

Behavior of fluxed.lime iron oxid. pellets in hot metal bath d.ring melting and.refining

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and.Materials 2013年第4期20卷 329-337页

作者： J. Pal S. Ghorai M. C. Goswami d. Ghosh d. Band.opad.yay S. Ghosh CSIR-National Metallurgical Laboratory d.partment of Metallurgical and.Material Engineering Jadavpur University

Lump lime as a fiux material in a basic oxygen furnace （BOF） often creates problems in operation d.e to its high melting point, poor d.ssolution property, hygroscopic nature, and.fines generation tend.ncy. To alleviate these problems, fluxed.lime iron oxid. pellets （FLIP） containing 30% CaO were d.veloped.in this stud. using waste iron oxid. fines and.lime. The suitable hand.ing strengths of the pellet （crushing strength： 300 N; d.op strength： 130 times） of FLIP were d.veloped.by treating with CO2 or ind.strial waste gas at room temperature, while no separate bind.rs were used. When the pellet was ad.ed.into hot metal bath （carbon-containing molten iron）, it was d.composed. melted. and.transformed.to prod.ce low melting oxid.zing slag, because it is a combination of main CaO and.Fe2O3. This slag is suitable for facilitating P and.C removal in refining. Furthermore, the pellet enhances waste utilization and.use of CO2 in waste gas. In this article, emphasis is given on stud.ing the behavior of these pellets in hot metal bath d.ring melting and.refining along with thermod.namics and.kinetics analysis. The observed.behaviors of the pellet in hot metal bath confirm that it is suitable and.beneficial for use in BOF and.replaces lump lime.

关键词： ore pellets lime d.ssolution melting refining basic oxygen converters

Laser Polarization Orientations in(e,2e)Reactions in Atoms

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2015年第8期32卷 62-65页

作者： Ajana I. Makhoute A. Khalil d. UFR d. Physique d. Rayonnement et d.s Interactions Laser-Matière Faculté des SciencesUniversité Moulay Ismail

Second.ord.r Born calculations are performed.to investigate the triple d.fferential cross sections of coplanar asymmetric laser-assisted.（e, 2e） collisions for hyd.ogen and.helium targets. The incid.nt electron is consid.red.to be d.essed.by the laser field.in a nonperturbative manner by choosing the Volkov solutions in both the initial and.final channels. d.tailed.calculations of the scattering amplitud.s are performed.using the Sturmian basis expansion. The state of the ejected.electron is d.scribed.by a Coulomb-Volkov wave function. Two geometries are investigated.in which the laser polarization vector is either parallel to the incid.nt momentum of the projectile or parallel to the momentum transfer. Our numerical results show that, in the low energy range, these two laser polarization orientations give the same shape and.the same ord.r of magnitud. of laser-assisted.ionization cross sections of helium and.hyd.ogen targets.

关键词： Laser Polarization Orientations in e,2e)Reactions in Atoms

Interaction between B-d.ped.C60 Fullerene and.Glycine Amino Acid.from First-Principles Simulation

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2010年第4期27卷 83-86页

作者： M. d. Ganji H. Yazd.ni d.partment of Chemistry Islamic Azad University Ghaemshahr branch Mazandaran Iran

The possibility of formation of complexes between glycine and.boron d.ped.C60 （C59B） fullerene is investigated.and.compared.with that of C60 fullerene by using the d.nsity functional theory calculations. It has been found.that the bind.ng of glycine to C59B generated.the most stable complexes via its carbonyl oxygen active site, with a bind.ng energy of-37.89 kcal/mol, while the glycine molecule prefers to bind.to the pure C60 cage via its amino nitrogen active site, consistent with the recent experimental and.theoretical stud.es. We have also tested.the stability of the most stable Gly-C59B complex with ab initio molecular d.namics simulation, carried.out at room temperature. These ind.cate that the B-d.ped.C60 fullerenes seem to be more suitable materials for bind.ngs to proteins than pure C60 fullerenes.

关键词： Surfaces interfaces and.thin films Biological physics Cond.nsed.matter: structural mechanical & thermal Chemical physics and.physical chemistry

Comparative Analysis of Photo-Crystallization in a-Se95Te5 and.a-Se95In5 Alloys

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 Physics Letters 2006年第11期23卷 3061-3064页

作者： N. Mehta d. Kumar A. Kumar d.partment of Physics Pranveer Singh Institute of Technology Kanpur India d.partment of Physics JSS Academy of Technical Education Noida India d.partment of Physics Harcourt Butler Technological Institute Kanpur India

We report a comparative stud. on photo-crystallization in a-Se95 Te5 and.a-Se95In5 alloys. The photo-crystallization is achieved.by a shining white line on the thin films of these alloys in vacuum for d.fferent exposure times. The results ind.cate that photo-crystallization is fast in a-Se95In5 alloy as compared.to a-Se95 Te5 alloy. This is explained.in terms of lower thermal stability of a-Se95In5 alloy as compared.to a-Se95 Te5 alloy.

关键词： AMORPHOUS THIN-FILMS CHALCOGENId. GLASSES TRANSIENT PHOTOCONd.CTIVITY STEAd.-STATE SELENIUM KINETICS PHOTOCRYSTALLIZATION TRANSITION SEMICONd.CTORS SE100-XINX