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一类区段赋时弧有色Petri网的可达性和可阻断性分析
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作者 方宇炜 张兰玲 韩曾晋 《控制理论与应用》 EI CAS CSCD 北大核心 1999年第4期487-491,共5页
为了描述和分析实际复杂实时系统,提出一种新的时间限制Perti网模型,区段赋时弧有色Petri网模型.这种Petri网在有色Petri网的库所输出弧上标注以输入库所的颜色为自变量的时间区间函数.基于一种充分考虑了系统时间不确定性的激发规... 为了描述和分析实际复杂实时系统,提出一种新的时间限制Perti网模型,区段赋时弧有色Petri网模型.这种Petri网在有色Petri网的库所输出弧上标注以输入库所的颜色为自变量的时间区间函数.基于一种充分考虑了系统时间不确定性的激发规则,给出了区段赋时弧有色Petri网的发生元序列时间界估计,并以此为依据,提出了基于状态类的可达性分析方法和可阻断性分析方法. 展开更多
关键词 有色PETRI网 可在性 可阻断 炼钢 连续铸钢
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Peroral cholangioscopy in the new millennium 被引量:12
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作者 Mansour A Parsi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第1期1-6,共6页
Peroral cholangioscopy was first described in 1970s and has recently gained popularity.Peroral cholangioscopy is appealing to therapeutic endoscopists because a direct intraluminal view of the biliary duct system offe... Peroral cholangioscopy was first described in 1970s and has recently gained popularity.Peroral cholangioscopy is appealing to therapeutic endoscopists because a direct intraluminal view of the biliary duct system offers possibilities for diagnosis and interventions beyond that which other imaging or endoscopic modalities can provide.As the image quality of cholangioscopies improves,so too does their diagnostic capability,and as their durability and maneuverability increases,so too does their potential use for therapeutic applications.This editorial is intended to provide a brief review of recent developments in peroral cholangioscopy and current indications for its use. 展开更多
关键词 Endoscopic retrograde cholangiopancreatography CHOLANGIOSCOPY Peroral cholangioscopy CHOLANGIOCARCINOMA Biliary stricture Pancreatic cancer BIOPSY Brush cytology
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MJO potential predictability and predictive skill in IAP AGCM 4.1
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作者 WANG Kun LIN Zhao-Hui +2 位作者 LING Jian YU Yue WU Cheng-Lai 《Atmospheric and Oceanic Science Letters》 CSCD 2016年第5期388-393,共6页
A 30-year hindcast was performed using version 4.1 of the IAP AGCM(IAP AGCM4.1), and its potential predictability of the MJO was then evaluated. The results showed that the potential predictability of the MJO is 13 ... A 30-year hindcast was performed using version 4.1 of the IAP AGCM(IAP AGCM4.1), and its potential predictability of the MJO was then evaluated. The results showed that the potential predictability of the MJO is 13 and 24 days, evaluated using the signal-to-error ratio method based on a single member and the ensemble mean, respectively. However, the MJO prediction skill is only9 and 10 days using the two methods mentioned above. It was further found that the potential predictability and prediction skill depend on the MJO amplitude in the initial conditions. Prediction initiated from conditions with a strong MJO amplitude tends to be more skillful. Together with the results of other measures, the current MJO prediction ability of IAP AGCM4.1 is around 10 days, which is much lower than other climate prediction systems. Furthermore, the smaller difference between the MJO predictability and prediction skill evaluated by a single member and the ensemble mean methods could be ascribed to the relatively smaller size of the ensemble member of the model.Therefore, considerable effort should be made to improve MJO prediction in IAP AGCM4.1 through application of a reasonable model initialization and ensemble forecast strategy. 展开更多
关键词 MJO IAP AGCM 4.1 PREDICTABILITY prediction skill
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The Qualitative Analysis of a Solution of a Series Maintenance System with Two Components 被引量:1
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作者 GUOWei-hua YANGMing-zeng 《Chinese Quarterly Journal of Mathematics》 CSCD 2003年第3期320-327,共8页
In this paper, firstly we study the series ma intenance system with two components, obtain its exsistence and uniqueness of a dynamic state nonnegative solution by strongly continuous semigroups of operator s theory. ... In this paper, firstly we study the series ma intenance system with two components, obtain its exsistence and uniqueness of a dynamic state nonnegative solution by strongly continuous semigroups of operator s theory. Then we prove that 0 is the eigenvalue of the system’s host operators, a nd finally we study the eigenvector of the eigenvalue 0. 展开更多
关键词 series connection maintenance system semig roups of operators nonnegative solution
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Fresh Water Demand Minimization in Residential Urban Buildings
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作者 Antonios Saragkas George Paschalidis 《Journal of Environmental Science and Engineering(A)》 2015年第4期210-214,共5页
In the last decades, there is a lot of discussion in many scientific fields, about the high importance of water as a basic element for the existence and the maintenance of life, aiming to the right and proper usage of... In the last decades, there is a lot of discussion in many scientific fields, about the high importance of water as a basic element for the existence and the maintenance of life, aiming to the right and proper usage of water in our everyday basic water-needs due to its limited resources and the growing demand. This research deals with simple ways and technological systems applicable in urban residential buildings for the better management of domestic fresh water, as far as its maintenance and sustainability. Main aim of the survey is the effective minimization of urban daily water usage. All measurements of water quantities have estimated in the imperial gallon (1 gallon = 4.546 liter), and in liter (1 liter = 0.2 gallon). 展开更多
关键词 Efficient urban water management sustainable buildings water resources sustainability
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Existence of almost periodic solutions to a class of non- autonomous functional integro-differential stochastic equations
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作者 Lijie Li Yu Feng Weiquan Pan 《International Journal of Technology Management》 2013年第3期46-49,共4页
In this paper, a class of non-autonomous functional integro-differential stochastic equations in a real separable Hilbert space is studied. When the operators A(t) satisfy Acquistapace-Terreni conditions, and with s... In this paper, a class of non-autonomous functional integro-differential stochastic equations in a real separable Hilbert space is studied. When the operators A(t) satisfy Acquistapace-Terreni conditions, and with some suitable assumptions, the existence and uniqueness of a square-mean almost periodic mild solution to the equations are obtained. 展开更多
关键词 Stochastic differential equations Square-mean almost periodic mild solution Acquistapace-Terreni conditions
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Prediction of VIGS efficiency by the Sfold program and its reliability analysis in Gossypium hirsutum 被引量:2
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作者 Xiaoyang Ge Jie Wu +10 位作者 Chaojun Zhang Qianhua Wang Yuxia Hou Zuoren Yang Zhaoen Yang Zhenzhen Xu Ye Wang Lili Lu Xueyan Zhang Jinping Hua Fuguang Li 《Science Bulletin》 SCIE EI CAS CSCD 2016年第7期543-551,共9页
Genetic transformation in some plant species, including cotton (Gossypium hirsutum), is hampered by laborious and time-consuming processes and often unachievable. Virus-induced gene silencing (VIGS) by double-stra... Genetic transformation in some plant species, including cotton (Gossypium hirsutum), is hampered by laborious and time-consuming processes and often unachievable. Virus-induced gene silencing (VIGS) by double-stranded RNAs can serve as a reverse-genetics tool to determine gene function. However, knockdown levels vary greatly when using a tobacco rattle virus-based vector that carries different cDNA fragments of a gene. How to choose the optional target fragment for high interference efficiency is very challenging. Addressing this challenge requires increasing the efficacy of small interference RNA (siRNA) in target fragment. Here, we describe a method to assess VIGS efficiency by comparing the following parameters of siRNA in target sequence: the disruptionenergy of the target (△Gdisruption), the differential stability of siRNA duplex ends (DSSE), and the internal stability at positions 9-14 of the siRNA antisense strand (AIS), which are calculated by Sfold program (http://sfold.wadsworth. org). We find that the siRNAs with low mGdisruption, high DSSE and high AIS have high activity and easily result in high VIGS efficiency by experimentally testing the actual knockdown levels of the four target genes, GhPDS, GhCLA1, GhAOS1, and GhCXE1 via choosing different target sequences for each gene. Therefore, the Sfold pro- gram can be used to analyze target sequences when car- rying out VIGS design to increase gene-silencing effects in plants. 展开更多
关键词 VIGS Sfold program SIRNA Targetsequences Gossypium hirsutum
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Global Existence of Classical Solutions for Some Oldroyd-B Model via the Incompressible Limit 被引量:3
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作者 Zhen LEI School of Mathematical Sciences, Fudan University, Shanghai 200433, China School of Mathematics and Statistics, Northeast Normal University, Changchun 130024, China. 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2006年第5期565-580,共16页
In this paper, we prove local and global existence of classical solutions for a system of equations concerning an incompressible viscoelastic fluid of Oldroyd-B type via the incompressible limit when the initial data ... In this paper, we prove local and global existence of classical solutions for a system of equations concerning an incompressible viscoelastic fluid of Oldroyd-B type via the incompressible limit when the initial data are sufficiently small. 展开更多
关键词 Incompressible limit Global existence Oldroyd model
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TRAVELING WAVE SOLUTIONS FOR A CLASS OF NONLINEAR DISPERSIVE EQUATIONS 被引量:38
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作者 LIJIBIN LIUZHENGRONG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2002年第3期397-418,共22页
The method of the phase plane is emploied to investigate the solitary and periodic traveling waves for a class of nonlinear dispersive partial differential equations.By using the bifurcation theory of dynamical system... The method of the phase plane is emploied to investigate the solitary and periodic traveling waves for a class of nonlinear dispersive partial differential equations.By using the bifurcation theory of dynamical systems to do qualitative analysis,all possible phase portraits in the parametric space for the traveling wave systems are obtained.It can be shown that the existence of a singular straight line in the traveling wave system is the reason why smooth solitary wave solutions converge to solitary cusp wave solution when parameters are varied.The different parameter conditions for the existence of solitary and periodic wave solutions of different kinds are rigorously determined. 展开更多
关键词 Solitary wave Periodic wave Integrable system Bifurcation of phase portraits Smoothness of wave
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THE -PROBLEM FOR HOLOMORPHIC (0,2)-FORMS ON PSEUDOCONVEX DOMAINS IN SEPARABLE HILBERT SPACES AND D.F.N. SPACES
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作者 J.LEE K.H.SHON 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2002年第1期67-74,共8页
This paper shows that the 8-problem for holomorphic (0, 2)-forms on Hubert spaces is solv-able on pseudoconvex open subsets. By using this result, the authors investigate the existence of the solution of the -equation... This paper shows that the 8-problem for holomorphic (0, 2)-forms on Hubert spaces is solv-able on pseudoconvex open subsets. By using this result, the authors investigate the existence of the solution of the -equation for holomorphic (0, 2)-forms on pseudoconvex domains in D.F.N. spaces. 展开更多
关键词 -prob1em Pseudoconvex domain Nuclear operator D.F.N. space
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Exact Controllability and Asymptotic Analysis for Shallow Shells
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作者 S.KAIZU N.SABU 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2007年第1期93-122,共30页
The authors consider the exact controllability of the vibrations of a thin shallow shell, of thickness 2ε with controls imposed on the lateral surface and at the top and bottom of the shell. Apart from proving the ex... The authors consider the exact controllability of the vibrations of a thin shallow shell, of thickness 2ε with controls imposed on the lateral surface and at the top and bottom of the shell. Apart from proving the existence of exact controls, it is shown that the solutions of the three dimensional exact controllability problems converge, as the thickhess of the shell goes to zero, to the solution of an exact controllability problem in two dimensions. 展开更多
关键词 Exact controllability Asymptotic analysis Shallow shells
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SENSITIVITY OF DARCY'S LAW TO DISCONTINUITIES
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作者 C.BERNARDI O.PIRONNEAU 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2003年第2期205-214,共10页
The authors investigate the sensitivity of hydrostatic pressure of flows through porous media with respect to the position of the soil layers. Indeed, these induce discontinuities of the porosity which is a piecewise ... The authors investigate the sensitivity of hydrostatic pressure of flows through porous media with respect to the position of the soil layers. Indeed, these induce discontinuities of the porosity which is a piecewise constant coefficient K of the partial differential equation satisfied by the pressure u and it leads to the computation of the derivative of u with respect to changes in position of discontinuity surface of K.The analysis relies on a mixed formulation of the problem. Preliminary numerical simulations are given to illustrate the theory. An application to a simple inverse problem is also given. 展开更多
关键词 Partial differential equations Flow through porous media Sensitivity Darcy's equation Topological optimization
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Modified Kadomtsev-Petviashvili Equation in (3+1) Dimensions:Multiple Front-Wave Solutions
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作者 A.M.Wazwaz XU Gui-Qiong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2015年第6期727-730,共4页
A modified Kadomtsev-Petviashvili (mKP) equation in (3+1) dimensions is presented. We reveal multiple front-waves solutions for this higher-dimensional developed equation, and multiple singular front-wave solutio... A modified Kadomtsev-Petviashvili (mKP) equation in (3+1) dimensions is presented. We reveal multiple front-waves solutions for this higher-dimensional developed equation, and multiple singular front-wave solutions as well. The constraints on the coefficients of the spatial variables, that assure the existence of these multiple front-wave solutions are investigated. We also show that this equation falls the Painleve test, and we conclude that it is not integrable in the sense of possessing the Painleve property, although it gives multiple front-wave solutions. 展开更多
关键词 modified Kadomtsev-Petviashvili equation multiple front-waves solutions Hirota's method
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