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RESEARcH ON THE cHAOS DYNAMIc MODEL OF RUNOFF

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Journal of Hydrodynamics 2000年第2期12卷 85-91页

作者： Jiang, chuanwen Quan, Xianzhang zhang, Yongchuan Hou, Zhijian Huazhong Univ of Science and Technology Wuhan China

The identification of chaos in the study of runoff serial was introduced and a dynamic model of runoff with the observed values of runoff serial was proposed. By checking the difference between the original serial and substitute serial, the nature of the runoff serial can be identified. This paper thus provides an effective method for studying the rule of runoff. The study of the chaos features of runoff and the understanding of its nonlinear dynamic model are of great significance to the understanding of the rules of runoff movement and the accurate prediction.

关键词： chaos theory Dynamics Models Runoff

Numerical Study for Turbulent Flow of Drag and Flow Noise with Wavy Wall

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Journal of shanghai jiaotong university(Science) 2011年第1期16卷 45-54页

作者：孟堃宇张怀新史勇林潘雨村 School of Naval Architecture Ocean and Civil EngineeringShanghai Jiaotong University

In this paper,a numerical simulation of flow-induced noise by the low Mach number turbulent flow with a sinusoidal wavy wall was presented based on the unsteady incompressible Navier-Stokes equations and Lighthill's acoustic *** eddy simulation (LES) was used to investigate the space-time flow field and the Smagorinsky sub-grid scale (SGS) model was introduced for turbulence *** Lighthill's acoustics analogy,the flow field simulated by LES was taken as near-field sound sources and radiated sound from turbulent flow was computed by the curle's integral formulation under the low Mach number *** spanwise wavy wall and streamwise wavy wall with various wall wave amplitudes were discussed to investigate their effects on reducing the drag and flow *** relationship between flow noise and drag on the wavy wall is also studied.

关键词： large eddy simulation (LES) wavy wall riblets turbulent flow flow noise

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矿石颗粒尺度分布的双圆算法

上海交通大学学报 2010年第3期44卷 384-388页

作者：应俊豪张秀彬上海交通大学电子信息与电气工程学院上海200240

针对高炉内矿石颗粒外形不规则和边缘暗淡模糊等特性,提出了双圆比的概念,运用图像预处理、彩色形态学平滑、颗粒点定位、颗粒最大区域扩张、双圆尺度检测等方法,能够很好地对矿石颗粒尺度分布情况进行检测.对比实验表明,该算法比经典... 详细信息

针对高炉内矿石颗粒外形不规则和边缘暗淡模糊等特性,提出了双圆比的概念,运用图像预处理、彩色形态学平滑、颗粒点定位、颗粒最大区域扩张、双圆尺度检测等方法,能够很好地对矿石颗粒尺度分布情况进行检测.对比实验表明,该算法比经典算法具有更高的准确度.

关键词：颗粒尺度分布双圆比形态学平滑平面划分计算机视觉

INFLUENcE OF Ge ON THE ANTIFERROMAGNETIc TRANSITION AND γ→ε MARTENSITIc TRANSFORMATION OF Fe-24Mn ALLOYS

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Acta Metallurgica Sinica(English Letters) 2002年第6期15卷 517-524页

作者： B. zhang, X. Lu Z.X. Qin, H.B. chang and X.Y. RuanDepartment of Plastic Deforming, shanghai jiaotong university, shanghai 200030, c.inaDepartment of Materials Science & Engineering, Dalian Railway Institute, Dalian 116028, c.ina Department of Plastic Deforming Shanghai Jiaotong University

The aims of the work were to study the effect of Ge (0-6wt. %) on the paramagnetic-antiferromagnetic transition and martensitic transformation of Fe-Mn alloy using the susceptibility, micro structure examination, X-ray diffraction (XRD) and latticeparameter measurement. Ge lowers the Néel temperature, TN, and enhances the magnetic susceptibility x, changing the Pauli paramagnetism above TN to paramagnetismstate obeying the curie Weiss law, which is essentially similar to that of γ-Fe-Mnalloys containing Al or Si; Ge depresses γ-ε martensitic transformation, whichattribute to Ge increasing the stacking fault energy; Moreover, Ge increases the lattice parameter of γ phase, and low content Ge increases the lattice parameter of γphase more than that of high Ge content. comparing Ge(4s24p2) with Si(3s23p2) and Al(3s2 3p1), which have the same outer-shell of electron structures, we found that their effects on the martensitic transformation of Fe-Mn alloy are completely different. The result suggests the outer-shell of electron is not the main factor of governing the Ms temperature of Fe-Mn alloy although it is essential in the alloy's antiferromagnetic transition. The relation among the Ms temperature, stacking fault energy and lattice parameter of austenite, has been discussed in brief.

关键词： antiferromagnetic transition martensitic transformation lattice parameter

The Analysis of the Geometric Structure of the Delayed Time Used in the Embedding Process in Predicting chaotic Time Series

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生物数学学报 1997年第1期12卷 23-26页

作者： Gu Shengshi Holden A V zhang H(applied mathematics Department,jiaotong university,shanghai 20030 P.R.c.ina.)(physiology Department centre for Nonlinear Studies,The university of Leeds,LS2 9JT,UK.) 上海交通大学应用数学系上海 200030 university of Loeds 美国

Using the logistic map,we implicitly analyse the geometric structure of the delayed time used in the embedding process in prediction of a chaotic time series.

关键词： Delayed time embedding process chaotic time series

Numerical Modeling of Dual-Pulse Shock Test Machine for Simulating Underwater Explosion Shock Loads on Warship Equipments

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Journal of shanghai jiaotong university(Science) 2009年第2期14卷 233-240页

作者：张志谊王贡献汪玉 Institute of Vibration Shock and Noise Shanghai Jiaotong University School of Logistics Engineering Wuhan University of Technology Naval Arming Academy

In order to qualify shock resistance performance of shipboard equipments and simulate real underwater explosion environment,a novel dual-pulse shock test machine is *** new machine will increase testing capability and meet special shock testing *** key parts of the machine,the velocity generator and the shock pulse regulator,play an important role in producing the positive acceleration pulse and the succeeding negative acceleration pulse,*** generated dual-pulse shock for test articles is in conformity with an anti-shock test *** on the impact theory,a nonlinear dynamic model of the hydraulically-actuated test machine is established with thorough analysis on its mechanism that involves conversion of gas potential energy and dissipation of kinetic *** results have demonstrated that the proposed machine is able to produce a double-pulse acceleration shock in the time domain or a desired shock response spectrum in the frequency domain,which sets up a base for the construction of the machine.

关键词： shock test machine underwater explosion (UNDEX) velocity generator shock pulse regulator

A SD rat model of thoracic aortic aneurysms

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上海医学 2007年第S1期30卷 65-66页

作者： cAO Jiumei, cHEN Ying, zhang Xin, LU Lin, HE Rumin, SHEN Weifeng. Department of cardiology, Ruijin Hospital, shanghai jiaotong university School of Medicine, shanghai, 200025, c.ina

Backgroud Thoracic aortic aneurysm (TAA) disease is a serious condition with both high mortality and morbidity rates associated with surgical therapy. Further understanding of the formation and progression of TAAs may provide novel, less invasive therapeutic strategies in patients with this devastating disease. Aneurysm formation is a complicated, dynamic process involving both cellular and extracellular processes. The mechanisms of TAA formation are poorly understood, mainly due to the lack of a useful and reproducible model. In 2003, Ikonomidis in South carolina developed a murine model of *** mouse model was less satisfactory because the small size of the murine aorta. The rat model has the advantage of larger aorta and the ability to do more research. Proper animal models are useful to understand the aetiology and evolution and they can be used to evaluate the efficacy of new *** The goal of this study was to test the hypothesis that abluminal calcium chloride application could creat TAAs in the SD *** Eight-week-old male Sprague-Dawley(SD) rats(n=60) were divided into two groups equally. All rats were anesthetized. An angiocath was then advanced through the mouth into the trachea under direct vision and connected to a rodent ventilator set at a respiratory rate of 180 breaths per minute. And their thoracic aortas were exposed via left thoracotomy. In the experiment group,a sponge soaked in 0.5 mol/L cacl2 was placed on the distal half of the exposed descending thoracic aorta under direct vision. As control group, 0.5 mol/L cacl2 was instead of 0.9% Nacl. After 15 min, the sponge was removed. Then the chest was closed. At 4,8,12 weeks, all animals undergoing fixation and aortic harvest were reanesthetized and the thorax was then opened beneath the xiphoid process. Potassium chloride was injected into the left ventricle under direct vision to arrest the heart. Then it was perfusion program and the entire animal was immersed in formal

关键词： thoracic aorta descending sponge distal exposed disruption eosin stained collagen

Direct transfer of A20 gene into pancreas protected mice from streptozotocin-induced diabetes

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Acta Pharmacologica Sinica 2004年第6期25卷 19-24页

作者： Lu-yang YU, Bo LIN, Zhen-lin zhang2, Li-he GUO3 Instituteof Biochemistryand cell Biology, shanghai Institutes for Biological Sciences, chinese Academy ofSciences, shanghai 200031 center for Preventing and Treating Osteoporosis, Osteoporosis Research Unit, 2 shanghai jiaotong universityAffiliated Sixth People’s Hospital, shanghai 200233, c.ina Institute of Biochemistry and cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences center for Preventing and Treating Osteoporosis Osteoporosis Research Unit Shanghai JiaoTong University Affiliated Sixth People’s Hospi

AIM: To investigate the efficiency of transfer of A20 gene into pancreas against STZ-induced diabetes. METHODS: PVP-plasmid mixture was directly transferred into the pancreatic parenchyma 2 d before STZ injection. The uptake of plasmid pcDNA3-LacZ or pcDNA3-A20 was detected by PcR and the expression of LacZ was confirmed by histological analysis with X-gal. A20 expression in the pancreas of pcDNA3-A20 transgenic mice was measured by RT-PcR and Western blots. Urine amylase, NO generation, and histological examination were examined. RESULTS: Injection of PVP-plasmid mixture directly into the pancreatic parenchyma increased urine amylase concentration 16 h after operation and reversed it to nearly normal 36 h later. On d 33 LacZ expression could be found in spleen, duodenum, and islets. The development of diabetes was prevented by direct A20 gene transferring into the pancreas and A20-mediated protection was correlated with suppression of NO production. The insulitis was ameliorated in A20-treated mice. cONcLUSION: Injection of PVP-plasmid mixture directly into the pancreatic parenchyma led to target gene expression in islets. Direct transfer of A20 gene into the pancreas protected mice from STZ-induced diabetes.

关键词： adenoviridae streptozocin insulin-dependent diabetes mellitus gene therapy nitric oxide glucose amylases reversed transcriptase polymerase chain reaction Western blotting

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椭圆定形曲线拟合问题若干新型算法

上海交通大学学报 2002年第8期36卷 1210-1213页

作者：雷志术张雁波上海交通大学应用数学系上海200240

针对一类特殊的参数辨识问题——椭圆定形曲线拟合问题 ,对原有的几何距离法提出了进化算法的求解方案 .基于反问题的求解思想给出了一种新的椭圆拟合度量 ,和原有度量相比 ,它既反映了拟合曲线的弯曲特性又便于数值求解 ,在该度量基础... 详细信息

针对一类特殊的参数辨识问题——椭圆定形曲线拟合问题 ,对原有的几何距离法提出了进化算法的求解方案 .基于反问题的求解思想给出了一种新的椭圆拟合度量 ,和原有度量相比 ,它既反映了拟合曲线的弯曲特性又便于数值求解 ,在该度量基础上构造出一种新型算法——加权新度量法 .数值模拟结果表明 ,提出的新方法是有效的。

关键词：椭圆定形曲线拟合问题椭圆拟合度量最小二乘法进化算法参数辨识加权新度量法