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CoN-Ⅰ高模量改性沥青制备及性能研究 被引量:1
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作者 李梦月 赵磊 +2 位作者 刘从峰 安平 闫翔鹏 《石油沥青》 2022年第1期35-40,共6页
高模量沥青是解决路面车辙问题的有效途径之一,对成品SBS沥青添加CoN-I高模量改性剂研制高模量沥青,对其三大指标及布氏黏度性能进行分析研究,研究结果表明:改性剂的加入使沥青的软化点升高、针入度减小、低温延性降低,黏度增大;当改性... 高模量沥青是解决路面车辙问题的有效途径之一,对成品SBS沥青添加CoN-I高模量改性剂研制高模量沥青,对其三大指标及布氏黏度性能进行分析研究,研究结果表明:改性剂的加入使沥青的软化点升高、针入度减小、低温延性降低,黏度增大;当改性剂掺量为17%时,调制的CoN-I高模量沥青性能指标满足高模量沥青技术指标标准;结合沥青气动回弹试验进一步分析验证沥青性能变化,沥青蠕变变形与针入度具有较好的相关性。 展开更多
关键词 con-Ⅰ高模量改性剂 沥青性能指标 气动回弹 蠕变变形
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Effects of Brassinosteroid on Salinity Tolerance of Cotton 被引量:5
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作者 束红梅 郭书巧 +2 位作者 巩元勇 帕尔哈提·买买提 倪万潮 《Agricultural Science & Technology》 CAS 2014年第9期1433-1437,1470,共6页
[Objective] In order to study the effects of brassinosteroid on salinity toler- ance of cotton. [Method] Three application modes (leaf application, root application and leaf/root application) of brassinosteroid for ... [Objective] In order to study the effects of brassinosteroid on salinity toler- ance of cotton. [Method] Three application modes (leaf application, root application and leaf/root application) of brassinosteroid for cotton under NaCI stress were de- signed to understand the effects of brassinosteroid on Na+ and CI- accumulation, osmotic adjustment substance (proline) and biomass accumulation of cotton under NaCI stress. [Result] NaCI inhibited the growth of cotton seedlings. Compared with the control group, the biomass of cotton seedlings was decreased, Na+ and CI- contents, MDA content and proline content were increased in cotton under NaCI stress. Under the NaCI stress, three application modes of brassinosteroid significant- ly improved the biomass, chlorophyll content in leaves, root activity and proline content; while Na~ and CI- content, MDA content were decreased. The enhancement of root activity and root physiological functions were more marked in root application and leaf/root application treatments than in leaf/root application treatment. [Conclu- sion] Three application modes of brassinosteroid all could alleviate the NaCI injuries on cotton, but root application and root/leaf application modes of brassinosteroid for cotton under NaCI stress are superior to the leaf application. 展开更多
关键词 COTTON NaCI stress BRASSINOSTEROID Na+and CI- content Proline con- tent
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APPLICATION OF HYBRID AERO-ENGINE MODEL FOR INTEGRATED FLIGHT/PROPULSION OPTIMAL CONTROL 被引量:4
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作者 王健康 张海波 +1 位作者 孙健国 李永进 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第1期16-24,共9页
The real-time capability of integrated flight/propulsion optimal control (IFPOC) is studied. An appli- cation is proposed for IFPOC by combining the onboard hybrid aero-engine model with sequential quadratic pro- gr... The real-time capability of integrated flight/propulsion optimal control (IFPOC) is studied. An appli- cation is proposed for IFPOC by combining the onboard hybrid aero-engine model with sequential quadratic pro- gramming (SQP). Firstly, a steady-state hybrid aero-engine model is designed in the whole flight envelope with a dramatic enhancement of real-time capability. Secondly, the aero-engine performance seeking control including the maximum thrust mode and the minimum fuel-consumption mode is performed by SQP. Finally, digital simu- lations for cruise and accelerating flight are carried out. Results show that the proposed method improves real- time capability considerably with satisfactory effectiveness of optimization. 展开更多
关键词 integrated flight/propulsion optimal control AERO-ENGINE hybrid model performance seeking con- trol sequential quadratic programming
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Clinical Study on Suspension Pancreatic-Duct-Jejunum End-to-Side Continuous Suture Anastomosis in Pancreaticoduodenectomy 被引量:5
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作者 Ke Dong Wei Xiong +1 位作者 Xiao-jiong Yu Chun Gu 《Chinese Medical Sciences Journal》 CAS CSCD 2013年第1期34-38,37-38,共5页
Objective To study the influence of Suspension Pancreatic-Duct-Jejunum End-to-Side Continuous Suture Anastomosis (SPDJCS) on the incidence of pancreatic fistula after pancreaticoduodenectomy, and to analyze its appl... Objective To study the influence of Suspension Pancreatic-Duct-Jejunum End-to-Side Continuous Suture Anastomosis (SPDJCS) on the incidence of pancreatic fistula after pancreaticoduodenectomy, and to analyze its applicability, safety, and efficacies. Methods A prospective controlled trial was conducted with 165 cases receiving pancreati- coduodenectomy in the Department of Hepatopancreatobiliary Surgery from January 2010 to May 2012. The patients were divided into Group A (end-to-end/end-to-side invaginated anastomosis, n=52), Group B (end-to-side mucosal anastomosis, n=48), and Group C (SPDJCS, n=65). The preoperative data, intra- operative data, and operative outcomes (incidence of pancreatic fistula, operation time, intraoperative blood loss, peritoneal drainage, peritoneal hemorrhage, peritoneal abscess, delayed gastric emptying, pulmonary infection, postoperative infection, blood transfusion, and perioperative mortality) were com- pared among the 3 groups. Results The total incidence of pancreatic fistula was 13.9% (23/165) in all the 165 patients. The inci- dence in Group A and Group B was 23.1% (12/52) and 18.8% (9/48), both higher than that in Group C [3.1% (2/65), both P〈0.05]. Group C showed significantly better outcomes than group A and B in terms of the opera- tion time (5.5±1.2 hours vs. 6.1±1.1 hours, 5.5±1.2 hours vs. 6.3±1.5 hours), volume of blood loss (412.0±205.0 mL vs. 525.0±217.0 mL, 412.0±205.0 mL vs. 514.0±217.0 mL), and postoperative drainage amount of plasma tubes (175.0±65.0 mE vs. 275.0±80.0 mL, 175.0±65.0 mL vs. 255.0±75.0 mL) (all P〈0.05), while Group A and Group B displayed no difference in these aspects (P〉0.05). As complications other than pancreatic fistula were concerned, the three groups were not different from each other (P〉0.05). Conclusions SPDJCS may have the effect of reducing the incidence of pancreatic fistula after pan- creaticoduodenectomy. It could be safe, practical and convenient technique of anastomosis for pancreaticoje- junostomy. 展开更多
关键词 PANCREATICODUODENECTOMY pancreatic fistula PANCREATICOJEJUNOSTOMY con- tinuous suture suspension of pancreatic duct
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Neural network based adaptive sliding mode control of uncertain nonlinear systems 被引量:4
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作者 Ghania Debbache Noureddine Goléa 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第1期119-128,共10页
The purpose of this paper is the design of neural network-based adaptive sliding mode controller for uncertain unknown nonlinear systems. A special architecture adaptive neural network, with hyperbolic tangent activat... The purpose of this paper is the design of neural network-based adaptive sliding mode controller for uncertain unknown nonlinear systems. A special architecture adaptive neural network, with hyperbolic tangent activation functions, is used to emulate the equivalent and switching control terms of the classic sliding mode control (SMC). Lyapunov stability theory is used to guarantee a uniform ultimate boundedness property for the tracking error, as well as of all other signals in the closed loop. In addition to keeping the stability and robustness properties of the SMC, the neural network-based adaptive sliding mode controller exhibits perfect rejection of faults arising during the system operating. Simulation studies are used to illustrate and clarify the theoretical results. 展开更多
关键词 nonlinear system neural network sliding mode con- trol (SMC) adaptive control stability robustness.
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Game-theoretic approach to power and admission control in hierarchical wireless sensor networks 被引量:2
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作者 Guofang Nan Zhifei Mao Minqiang Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第2期216-224,共9页
Power efficiency and link reliability are of great impor- tance in hierarchical wireless sensor networks (HWSNs), espe- cially at the key level, which consists of sensor nodes located only one hop away from the sink... Power efficiency and link reliability are of great impor- tance in hierarchical wireless sensor networks (HWSNs), espe- cially at the key level, which consists of sensor nodes located only one hop away from the sink node called OHS. The power and admission control problem in HWSNs is comsidered to improve its power efficiency and link reliability. This problem is modeled as a non-cooperative game in which the active OHSs are con- sidered as players. By applying a double-pricing scheme in the definition of OHSs' utility function, a Nash Equilibrium solution with network properties is derived. Besides, a distributed algorithm is also proposed to show the dynamic processes to achieve Nash Equilibrium. Finally, the simulation results demonstrate the effec- tiveness of the proposed algorithm. 展开更多
关键词 hierarchical network power control admission con- trol game theory double-pricing scheme.
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Cooperative Differential Game for Model Energy-Bandwidth Efficiency Tradeoff in the Internet of Things 被引量:3
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作者 LIN Fuhong LIU Qian +2 位作者 ZHOU Xianwei CHEN Yueyun HUANG Daochao 《China Communications》 SCIE CSCD 2014年第1期92-102,共11页
Internet of Things (IoT) refers to an infrastructure which enables the forms of com- munication and collaboration between people and things, and between things themselves. In order to improve its performance, we pre... Internet of Things (IoT) refers to an infrastructure which enables the forms of com- munication and collaboration between people and things, and between things themselves. In order to improve its performance, we present a tradeoff between bandwidth and energy con- sumption in the loT in this paper. A service providing model is built to find the relation- ship between bandwidth and energy consump- tion using a cooperative differential game mo- del. The game solution is gotten in the condi- tion of grand coalition, feedback Nash equili- brium and intermediate coalitions and an allo- cation policy is obtain by Shapley theory. The results are shown as follows. Firstly, the per- formance of IoT decreases with the increasing of bandwidth cost or with the decreasing of en- ergy cost; secondly, all the nodes in the IoT com- posing a grand coalition can save bandwidth and energy consumption; thirdly, when the fac- tors of bandwidth cost and energy cost are eq- ual, the obtained number of provided services is an optimised value which is the trade-off between energy and bandwidth consumption. 展开更多
关键词 Internet of things bandwidth con- sumption energy consumption cooperative diff- erential game theory
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New CFAR target detector for SAR images based on kernel density estimation and mean square error distance 被引量:4
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作者 Yi Cui Jian Yang Xinzheng Zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第1期40-46,共7页
A new constant false alarm rate (CFAR) target detector for synthetic aperture radar (SAR) images is developed. For each pixel under test, both the local probability density function (PDF) of the pixel and the cl... A new constant false alarm rate (CFAR) target detector for synthetic aperture radar (SAR) images is developed. For each pixel under test, both the local probability density function (PDF) of the pixel and the clutter PDF in the reference window are estimated by the non-parametric density estimation. The target detector is defined as the mean square error (MSE) distance between the two PDFs. The CFAR detection in SAR images having multiplicative noise is achieved by adaptive kernel bandwidth proportional to the clutter level. In addition, for obtaining a threshold with respect to a given probability of false alarm (PFA), an unsupervised null distribution fitting method with outlier rejection is proposed. The effectiveness of the proposed target detector is demonstrated by the experiment result using the RADATSAT-2 SAR image. 展开更多
关键词 synthetic aperture radar (SAR) target detection con- stant false alarm rate (CFAR).
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Variational Assimilation of GPS Precipitable Water Vapor and Hourly Rainfall Observations for a Meso-βScale Heavy Precipitation Event During the 2002 Mei-Yu Season 被引量:2
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作者 张盟 倪允琪 张福青 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2007年第3期509-526,共18页
Recent advances in Global Positioning System (GPS) remote sensing technology allow for a direct estimation of the precipitable water vapor (PWV) from delayed signals transmitted by GPS satellites, which can be ass... Recent advances in Global Positioning System (GPS) remote sensing technology allow for a direct estimation of the precipitable water vapor (PWV) from delayed signals transmitted by GPS satellites, which can be assimilated into numerical models with four-dimensional variational (4DVAR) data assimilation. A mesoscale model and its 4DVAR system are used to access the impacts of assimilating GPS-PWV and hourly rainfall observations on the short-range prediction of a heavy rainfall event on 20 June 2002. The heavy precipitation was induced by a sequence of meso-β-scale convective systems (MCS) along the mei-yu front in China. The experiments with GPS-PWV assimilation cluster and also eliminated the erroneous rainfall successfully simulated the evolution of the observed MCS systems found in the experiment without 4DVAR assimilation. Experiments with hourly rainfall assimilation performed similarly both on the prediction of MCS initiation and the elimination of erroneous systems, however the MCS dissipated much sooner than it did in observations. It is found that the assimilation-induced moisture perturbation and mesoscale low-level jet are helpful for the MCS generation and development. It is also discovered that spurious gravity waves may post serious limitations for the current 4DVAR algorithm, which would degrade the assimilation efficiency, especially for rainfall data. Sensitivity experiments with different observations, assimilation windows and observation weightings suggest that assimilating GPS-PWV can be quite effective, even with the assimilation window as short as 1 h. On the other hand, assimilating rainfall observations requires extreme cautions on the selection of observation weightings and the control of spurious gravity waves. 展开更多
关键词 GPS precipitable water vapor four-dimensional variational assimilation meso-β-scale con- vective system
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Multireference configuration interaction potential curve and analytical potential energy function of the ground and low-lying excited states of CdSe 被引量:1
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作者 高峰 杨传路 +1 位作者 胡振彦 王美山 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第12期3668-3674,共7页
The potential energy curves (PECs) of the ground state (^3∏) and three low-lying excited states (^1∑, ^3∑,^1∏) of CdSe dimer have been studied by employing quasirelativistic effective core potentials on the ... The potential energy curves (PECs) of the ground state (^3∏) and three low-lying excited states (^1∑, ^3∑,^1∏) of CdSe dimer have been studied by employing quasirelativistic effective core potentials on the basis of the complete active space self-consistent field method followed by multireference configuration interaction calculation. The four PECs are fitted to analytical potential energy functions using the Murrel-Sorbie potential function. Based on the PECs, the vibrational levels of the four states are determined by solving the Schrodinger equation of nuclear motion, and corresponding spectroscopic constants are accurately calculated. The equilibrium positions as well as the spectroscopic constants and the vibrational levels are reported. By our analysis, the ^3∏ state, of which the dissociation asymptote is Cd(^1S) + Se(^3p), is identified as a ground state of CdSe dimer, and the corresponding dissociation energy is estimated to be 0.39eV. However, the first excited state is only 1132.49cm^-1 above the ground state and the ^3∑ state is the highest in the four calculated states. 展开更多
关键词 potential energy curve multireference configuration interaction spectroscopic con- stants vibrational levels
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Generalized projective synchronization of fractional-order complex networks with nonidentical nodes 被引量:1
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作者 刘金桂 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第12期130-134,共5页
This paper investigates the synchronization problem of fractional-order complex networks with nonidentical nodes. The generalized projective synchronization criterion of fractional-order complex networks with order 0 ... This paper investigates the synchronization problem of fractional-order complex networks with nonidentical nodes. The generalized projective synchronization criterion of fractional-order complex networks with order 0 〈 q 〈 1 is obtained based on the stability theory of the fractional-order system. The control method which combines active control with pinning control is then suggested to obtain the controllers. Furthermore, the adaptive strategy is applied to tune the control gains and coupling strength. Corresponding numerical simulations are performed to verify and illustrate the theoretical results. 展开更多
关键词 fractional-order complex networks generalized projective synchronization pinning con- trol adaptive coupling law
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Percutaneous panvascular intervention in an unusual case of extensive atherosclerotic disease 被引量:1
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作者 Rajesh Vijayvergiya Dheeraj Garg Saroj K Sinha 《World Journal of Cardiology》 CAS 2012年第2期48-53,共6页
It is common to see patients with atherosclerotic coronary disease and peripheral arterial disease in routine clinical practice. One needs to have a comprehensive and integrated multi-speciality approach and panvascul... It is common to see patients with atherosclerotic coronary disease and peripheral arterial disease in routine clinical practice. One needs to have a comprehensive and integrated multi-speciality approach and panvascular revascularization in such patients. We report a 54-year-old diabetic hypertensive male with extensive atherosclerotic coronary and peripheral arterial disease, who presented with congestive heart failure, claudication of both lower limbs and mesenteric ischemia. He underwent successful percutaneous panvas- cular revascularization of coronary, renal, mesenteric, aorto-iliac and superficial femoral arteries. Long-term patency of all the stents was also documented. 展开更多
关键词 Atherosclerosis Aorto-iliac bifurcation Coronary ARTERY DISEASE Chronic MESENTERIC ischemia con- trast induced NEPHROPATHY C-reactive protein Inferior MESENTERIC ARTERY Peripheral arterial DISEASE STENTS
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Artificial boundary conditions for Euler–Bernoulli beam equation 被引量:1
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作者 Shao-Qiang Tang Eduard G.Karpov 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2014年第5期687-692,共6页
In a semi-discretized Euler-Bernoulli beam equa- tion, the non-nearest neighboring interaction and large span of temporal scales for wave propagations pose challenges to the effectiveness and stability for artificial ... In a semi-discretized Euler-Bernoulli beam equa- tion, the non-nearest neighboring interaction and large span of temporal scales for wave propagations pose challenges to the effectiveness and stability for artificial boundary treat- ments. With the discrete equation regarded as an atomic lattice with a three-atom potential, two accurate artificial boundary conditions are first derived here. Reflection co- efficient and numerical tests illustrate the capability of the proposed methods. In particular, the time history treatment gives an exact boundary condition, yet with sensitivity to nu- merical implementations. The ALEX (almost EXact) bound- ary condition is numerically more effective. 展开更多
关键词 Euler-Bernoulli beam. Artificial boundary con- dition - Wave propagation
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THE HAUSDORFF DIMENSION AND MEASURE IN GENERALIZED GEOMETRIC GRAPH DIRECTED CONSTRUCTION
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作者 苏峰 赵兴球 《数学物理学报(A辑)》 CSCD 北大核心 1997年第S1期162-167,共6页
Abthors introduce the notation of generalized geometric constructions in Rm generated by a directed graph G and by a sequence of similarity ratios which are labelled with the edges of this graph. In this paper, it is ... Abthors introduce the notation of generalized geometric constructions in Rm generated by a directed graph G and by a sequence of similarity ratios which are labelled with the edges of this graph. In this paper, it is obtained the Hausdorff dimension and measure of this construction object for some cases. 展开更多
关键词 HAUSDORFF DIMENSION HAUSDORFF MEASURE GENERALIZED GRAPH dirceted con- struction
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Branch Structure of Corona Discharge: Experimental Simulation and Chemical Properties
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作者 邹吉军 刘昌俊 《Plasma Science and Technology》 SCIE EI CAS CSCD 2004年第6期2585-2588,共4页
The branch structure of corona discharge has been investigated via C2H2 corona discharge. Carbon filament with excellent branch structure is formed in the discharge. This carbon filament offers a direct mimic of the b... The branch structure of corona discharge has been investigated via C2H2 corona discharge. Carbon filament with excellent branch structure is formed in the discharge. This carbon filament offers a direct mimic of the branch structure of corona discharge. It provides a very useful way to study on the average energy, physical and chemical characteristics of corona discharge. On this basis, the chemical property of corona discharge for methane conversion is discussed. 展开更多
关键词 corona discharge branch structure ACETYLENE carbon filament methane con- version
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Non-Uniformity of Heavy-Ion Beam Irradiation on a Direct-Driven Pellet in Inertial Confinement Fusion
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作者 Leila GHOLAMZADEH Abbas GHASEMIZAD 《Plasma Science and Technology》 SCIE EI CAS CSCD 2011年第1期44-49,共6页
Heavy-ion-driven fusion (HIF) is a scheme to achieve inertial confinement fusion (ICF). Investigation of the non-uniformity of heavy-ion beam (HIB) irradiation is one of the key issues for ICF driven by powerful... Heavy-ion-driven fusion (HIF) is a scheme to achieve inertial confinement fusion (ICF). Investigation of the non-uniformity of heavy-ion beam (HIB) irradiation is one of the key issues for ICF driven by powerful heavy-ion beams. Ions in HIB impinge on the pellet surface and deposit their energy in a relatively deep and wide area. Therefore, the non-uniformity of HIB irradiation should be evaluated in the volume of the deposition area in the absorber layer. By using the OK1 code with some corrections, the non-uniformity of heavy-ion beam irradiation for the different ion beams on two kinds of targets were evaluated in 12-beam, 20-beam, 60-beam and 120-beam irradiation schemes. The root-mean-square (RMS) non-uniformity value becomes aRMS = 8.39% in an aluminum mono-layer pellet structure and aRMS = 6.53% in a lead-aluminum layer target for the 12-uranium-beam system. The RMS non-uniformity for the lead-aluminum layer target was lower than that for the mono-layer target. The RMS and peak-to-valley (PTV) non-uniformities are reduced with the increase in beam number, and low at the Bragg peak layer. 展开更多
关键词 heavy ion beam deposition energy irradiation non-uniformity inertial con- finement fusion Bragg peak layer
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ON A NEW 3D MODEL FOR INCOMPRESSIBLE EULER AND NAVIER-STOKES EQUATIONS
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作者 王术 《Acta Mathematica Scientia》 SCIE CSCD 2010年第6期2089-2102,共14页
In this paper, we investigate some new properties of the incompressible Euler and Navier-Stokes equations by studying a 3D model for axisymmetric 3D incompressible Euler and Navier-Stokes equations with swirl. The 3D ... In this paper, we investigate some new properties of the incompressible Euler and Navier-Stokes equations by studying a 3D model for axisymmetric 3D incompressible Euler and Navier-Stokes equations with swirl. The 3D model is derived by reformulating the axisymmetric 3D incompressible Euler and Navier-Stokes equations and then neglecting the convection term of the resulting equations. Some properties of this 3D model are reviewed. Finally, some potential features of the incompressible Euler and Navier-Stokes equations such as the stabilizing effect of the convection are presented. 展开更多
关键词 finite time singularities nonlinear nonlocal system stabilizing effect of con- vection incompressible Euler and Navier-Stokes equations
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Complications Related to Transcatheter Occlusion of Atrial Septal Defect with Amplatzer Septal Occluder in Children
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作者 王树水 李渝芬 +2 位作者 张智伟 王慧深 钱明阳 《South China Journal of Cardiology》 CAS 2004年第2期75-79,共5页
Objectives To investigate the causes, theraputic and preventive methods of com- plications associated with transcatheter occlusion of at- rial septal defect ( ASD) using the Amplatzer septal oc- cluder (ASO) in childr... Objectives To investigate the causes, theraputic and preventive methods of com- plications associated with transcatheter occlusion of at- rial septal defect ( ASD) using the Amplatzer septal oc- cluder (ASO) in children. Methods 289 cases un- derwent transcatheter closure of ASD with ASO. Com- plications occurred in 9 cases. The complications in procedure included systemic circulatory systemic air embolism in 2, pulmonary air embolism in 1, pericar- dial tamponade in 1, ASO malposition requiring emer- gency surgical removal in 1, transient atrial extrasysto- les in 1 and sizing balloon rupture in 1 case. 2 cases with postoperative complications were found in the fol- low-up studies. These included perforation of mitral valve and ASO partially dislodged. In this study, 5 children with intraoperative complication received e- mergency therapy including surgical intervention, and others needed only follow-up, as the complications were transient or asymptomatic. Results There were no children death in this study. The 5 cases who re- ceived treatment were completely healing, and the oth- ers with intra - procedure complications were also had no sequela existed. Cases with mitral valve and ASO partially dislodged were still in follow-up studies, as the 2 patients having no symptoms. Conclutions Air embolism were occurred easily in atrial septal defect cases who received ASO therapy. Complications mainly caused by inappropriate operative procedure and some complications needed emergency treatments. Follow-up studies were important to cases with transcatheter oc- clusion therapy. 展开更多
关键词 Atrial septal defects Catheteriza- tion Complication Atrial septal defect (ASD) was a common con- genital heart defect with an estimated prevalence of 3. 78/10 000 live . In recent years the meth- od of surgical treatment of ASD was s
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Geometric Characterizations of Convergence for Sequences of Continuous Linear Functionals
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作者 徐际宏 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2001年第3期371-376,共6页
We prove the following main result: Let X be a normed linear space,fn ∈ X*\{θ},Hn = {x ∈ X: fn(x) = l},n = 0, 1,2,...Then w* - limfn = f0 iff H0 lim inf Hn and θ limsup Hn; when X is a reflexive Banach space, l... We prove the following main result: Let X be a normed linear space,fn ∈ X*\{θ},Hn = {x ∈ X: fn(x) = l},n = 0, 1,2,...Then w* - limfn = f0 iff H0 lim inf Hn and θ limsup Hn; when X is a reflexive Banach space, lim ||fn - f0|| = 0. If and only if θ w-limsup Hn Ho It simplifies the related results in [1]. 展开更多
关键词 norm-(weak- weak*-) convergence Kuratowski(Mosco- Wijsman-) con- vergence.
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Experimental study on electrical conductivity of dunite at high temperature and pressure——The evidence of electrical conductivity of cold mantle in the Gaize-Lugu area 被引量:5
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作者 WANG Duojun LI Heping +5 位作者 LIU Congqiang ZHAO Zhidan MO Xuanxue GUO Tieying SU Gengli DING Dongye 《Chinese Science Bulletin》 SCIE EI CAS 2001年第24期2089-2092,共4页
The electrical conductivities of the dunite from the Qinghai-Xizang (Tibetan) Plateau were measured with the impedance spectra method at 1.0-4.0 GPa and 643-1093 K. The experimental results indicated that activation e... The electrical conductivities of the dunite from the Qinghai-Xizang (Tibetan) Plateau were measured with the impedance spectra method at 1.0-4.0 GPa and 643-1093 K. The experimental results indicated that activation enthalpies of the dunite are smaller than 0.9 eV, the conduction mechanism in dunite may be attributed to the mixed electrical conduction involving grain interiors and boundaries. On the basis of the results of this experiment, we can deduce that there exists cold mantle in the area of Gaize-Lugu in the Qinghai-Xizang (Tibetan) Plateau by reverse methods from the magnetotelluric sounding data (conductivity-depths profile) available for western Tibet. The result provides the present cold mantle viewpoint with strong proof on the basis of high temperature and pressure experiments. 展开更多
关键词 high temperature and PRESSURE DUNITE electrical con- ductivity conduction mechanism COLD mantle.
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