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Analysis of optimal initial glide conditions for hypersonic glide vehicles

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Chinese Journal of Aeronautics 2014年第2期27卷 217-225页

作者： yan Xiaodong Lyu Shi tang Shuo School of Astronautics Northwestern Polytechnical University Science and Technology on Aerospace Flight Dynamics Laboratory

Hypersonic glide vehicles （HGVs） are launched by a solid booster and glide through the atmosphere at high speeds. HGVs will be important means for rapid long-range delivery in the future. Given that the glide is unpowered, the initial glide conditions （IGCs） are crucial for flight. This paper aims to find the optimal IGCs to improve the maneuverability and decrease the con- straints of HGVs. By considering the IGCs as experiment factors, we design an orthogonal table with three factors that have five levels each by using the orthogonal experimental design method. Thereafter, we apply the Gauss pseudospectral method to perform glide trajectory optimization by using each test of the orthogonal table as the initial condition. Based on the analytic hierarchy process, an integrated indicator is established to evaluate the IGCs, which synthesizes the indexes of the maneuverability and constraints. The integrated indicator is calculated from the trajectory opti- mization results. Finally, optimal IGCs and valuable conclusions are obtained by using range anal- ysis, variance analysis, and regression analysis on the integrated indicator.

关键词： Analytic hierarchy process Hypersonic glide vehicles Optimization Orthogonat experimentaldesign Trajectory

Growth and Cd Accumulation of Orychophragmus violaceus as Affected by Inoculation of Cd-Tolerant Bacterial Strains

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Pedosphere 2014年第3期24卷 322-329页

作者： LIANG Xia HE Chi-Quan NI Gang tang Gui-E CHEN Xue-ping LEI yan-Ru School of Environmental and Chemical Engineering Shanghai University

Beneficial interactions between microorganisms and plants, particularly in the rhizosphere, are a research area of global interest. Four cadmium(Cd)-tolerant bacterial strains were isolated from heavy metal-contaminated sludge and their effects on Cd mobility in soil and the root elongation and Cd accumulation of Orychophragmus violaceus were explored to identify the capability of metalresistant rhizobacteria for promoting the growth of O. violaceus roots on Cd-contaminated soils. The isolated strains, namely, Bacillus subtilis, B. cereus, B. megaterium, and Pseudomonas aeruginosa, significantly enhanced the plant Cd accumulation. The Cd concentrations in the roots and shoots were increased by up to 2.29- and 2.86-fold, respectively, by inoculation of B. megaterium, as compared with the uninoculated control. The bacterial strains displayed different effects on the shoot biomass. Compared with the uninoculated plants, the shoot biomass of the inoculated plants was slightly increased by B. megaterium and significantly decreased by the other strains. B. megaterium was identified as the best candidate for enhancing Cd accumulation in O. violaceus. Thus, this study provides novel insight into the development of plant-microbe systems for phytoremediation.

关键词： heavy metals phytoremediation plant-microbe systems rhizobacteria soil contamination

SDE decomposition and A-type stochastic interpretation in nonequilibrium processes

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Frontiers of physics 2017年第6期12卷 1-9页

作者： Ruoshi Yuan Ying tang ping Ao Key Laboratory of Systems Biomedicine Ministry of Education Shanghai Center for Systems Biomedicine Shanghai Jiao Tong University Shanghai 200240 China Department of Physics and Astronomy Shanghai-Jiao Tong University Shanghai 200240 China

An innovative theoretical framework for stochastic dynamics based on the decomposition of a stochas- tic differential equation （SDE） into a dissipative component, a detailed-balance-breaking component, and a dual-role potential landscape has been developed, which has fruitful applications in physics, engineering, chemistry, and biology. It introduces the A-type stochastic interpretation of the SDE beyond the traditional Ito or Stratonovich interpretation or even the a-type interpretation for multi- dimensional systems. The potential landscape serves as a Hmniltonian-like function in nonequilibrimn processes without detailed balance, which extends this important concept from equilibrium statistical physics to the nonequilibrium region. A question on the uniqueness of the SDE decomposition was recently raised. Our review of both the mathematical and physical aspects shows that uniqueness is guaranteed. The demonstration leads to a better understanding of the robustness of the novel frame- work. In addition, we discuss related issues including the limitations of an approach to obtaining the potential function from a steady-state distribution.

关键词： nonequilibrium statistical physics nonequilibrium potential Lyapunov function,nonlinear stochastic dynamics systems biology

Method for Improving Transverse Wall Thickness Precision of Seamless Steel Tube Based on Tube Rotation

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Journal of Iron and Steel Research International 2015年第10期22卷 924-930页

作者： Yong-zheng JIANG Hua-ping tang State Key Laboratory of High Performance Complex Manufacturing Central South University

The tube rotation method （TRM） refers to the rotational movement of steel tube about its axis as well as translation in rolling direction in stretch reducing rolling process. The influence of the TRM on transverse wall thickness precision of seamless steel tube was studied. Thickness distribution of the TRM was obtained by superimposing the thickened amount of single pass rolling. Results show that the TRM can effectively improve the evenness of thickness distribution. In order to analyze the influence mechanism of the TRM, the finite element method was adopted to simulate the thickness distribution in stretch reduction process. Results show that the TRM changes the roundtrip flow between two fix places of conventional stretch reducing and inhibits the directional accumulation of metal. In addition, the TRM has a correction effect on thickness cusp. All these advantages of the TRM help to improve the transverse wall thickness precision of seamless steel tube.

关键词： seamless tube stretch reducing transverse unevenness tube rotation method

The action of medicinal animal horns on Escherichia coli growth investigated by microcalorimetry and chemometric analysis

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Chinese Science Bulletin 2010年第26期55卷 2945-2950页

作者： yan Dan HAN YuMei LUO Jiaoyang ZHANG ping tang HuiYing PENG Cheng XIAO XiaoHe Institute of Chinese Medicine 302 Hospital of People's Liberation Army Beijing 100039 China Chengdu University of Traditional Chinese Medicine Chengdu 610075 China Chongqing Institute of Technology Chongqing 400050 China

The action of Cornu Cervi Pantotrichum (CCP), Cornu Cervi (CC) and Cornu Saigae Tataricae (CST) on Escherichia coli growth were investigated using microcalorimetry to find the heat change regularity of microbial growth. The similarity of thermogenic curves and thermodynamics parameters were investigated as evaluation index, such as the growth rate constant in the first expo- nential phase (k1), maximum power in the first exponential phase (P1), maximum power in the secondary exponential phase (P2), peak time in the first exponential phase (T1), peak time in the stationary phase (T2) and the total heat production in stage 1 (Q1), and the total heat production in stage 2 (Q2). Chemometric analysis was used as a reference for the bioactivity evaluation of medicinal animal horns. The results indicated that the similarity between CST and the control was smaller than that between CCP, CC and the control. Both CCP and CC could increase the heat in the microbial growth, whereas CST decreased it. The biotic thermal activity of different medicinal animal horns was objectively, qualitatively, and quantitatively evaluated by the similarity of thermogenic curves and thermodynamics parameters analysis.

关键词：生长变化规律化学计量学药用动物大肠杆菌微生物生长相似性评估热力学参数生物活性评价

METHOD TO CALCULATE BENDING CENTER AND STRESS INTENSITY FACTORS OF CRACKED CYLINDER UNDER SAINT-VENANT BENDING

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Applied Mathematics and Mechanics(English Edition) 2001年第1期22卷 79-88页

作者： tang Pen-ji(汤任基) tang Xin-yan(汤昕燕) Department of Engineering Mechanics Shanghai Jiaotong University Shanghai 200030 P R China Agricultural Engineering College Nanjing Agricultural University Nanjing 210032 P R China

Using the single crack solution and the regular solution elf plane harmonic function, the problem of Saint-Venant bending of a cracked cylinder by a transverse force was reduced to solving two sets of integral equations and its general solution was then obtained. Based on the obtained solution, a method to calculate the bending center and the stress intensity factors of the cracked cylinger whose cross-section is not thin-walled, but of small torsion rigidity is proposed. Some numerical examples are given.

关键词： cracked cylinger Saint-Venant bending bending center stress intensity factors integral equation method

Current application situation of gastrointestinal endoscopy in China

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World Journal of Gastroenterology 2013年第19期19卷 2950-2955页

作者： Xiu-Li Zhang Zhong-Sheng Lu ping tang Jin-yan Kong Yun-Sheng yang Department of Gastroenterology and Hepatology Chinese PLA General Hospital

AIM:To study the current application situation of gastrointestinal(GI) endoscopy in China's ***:From 12 August,2011 to 15 February,2012,draft questionnaires were sent by e-mail to 289 hospital-based GI endoscopy units,including units with three levels(provincial,prefecture and county level) in China's *** the surveyed GI endoscopy units were state-owned and *** were compared using χ 2 *** between groups were performed using the Mann-Whitney U test.A probability of P < 0.05 was considered to represent a statistically significant ***:Based on satisfactory replies,169/279(60.6%) of units were enrolled in the survey,which covered 28 provinces(90.3%,28/31) in China's *** with published survey data,the number of GI endoscopes per unit has increased by nearly three times(from 2.9 to 9.3) in the past *** 33 of 169(19.5%) endoscopy units possessed an X-ray machine,which was mainly owned by provincial endoscopy units(43.2%,19/44).Video capsule endoscopes,which were almost unavailable ten years ago,were owned by 20.7%(35/169) of GI endoscopy *** submucosal dissection could be performed by 36.4%(19/44) of the provincial units,which was significantly higher than the prefecture level(9.9%,P < 0.01) and county level(0.0%,P < 0.01) units,***:Rapid development in GI endoscopy has been made in China's Mainland,and major diagnostic endoscopes and therapeutic endoscopy procedures are predominantly used in large endoscopy units.

关键词： Application situation Gastrointestinal endoscopy Video capsule endoscopy Endoscopic submucosal dissection

Model-driven path planning for robotic plasma cutting of branch pipe with single Y-groove based on pipe-rotating scheme

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Advances in Manufacturing 2024年第1期12卷 94-107页

作者： yan Liu Qiu tang Xin-Cheng Tian School of Control Science and Engineering Shandong UniversityJinan250061People’s Republic of China Engineering Research Center of Intelligent Unmanned System Ministry of EducationJinan250061People’s Republic of China School of Mechanical and Electronic Engineering Shandong Jianzhu UniversityJinan250101People’s Republic of China

The automatic cutting of intersecting pipes is a challenging task in *** improved automation and accuracy,this paper proposes a model-driven path planning approach for the robotic plasma cutting of a branch pipe with a single ***,it summarizes the intersection forms and introduces a dual-pipe intersection *** on this model,the moving three-plane structure(a description unit of the geometric characteristics of the intersecting curve)is constructed,and a geometric model of the branch pipe with a single Y-groove is ***,a novel mathematical model for plasma radius and taper compensation is ***,the compensation model and groove model are integrated by establishing movable ***,to prevent collisions between the plasma torch and workpiece,the torch height is planned and a branch pipe-rotating scheme is *** the established models and moving frames,the planned path description of cutting robot is provided in this novel *** accuracy of the proposed method is verified by simulations and robotic cutting experiments.

关键词： Automatic groove cutting of intersecting pipes Model-driven robot path planning Plasma beam radius and taper compensation

Practical ф_0 -stability of switched stochastic nonlinear systems and corresponding stochastic perturbation theory

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控制理论与应用（英文版） 2013年第1期11卷 92-95页

作者： yan ZHAO ping ZHAO School of Mathematical Sciences University of Jinan School of Electrical Engineering University of Jinan

The aim of this paper is to study the practical φ0-stability in probability （Pφ0 SiP） and practical ~o-stability in pth mean （Pφ0SpM） of switched stochastic nonlinear systems. Sufficient conditions on such practical properties are obtained by using the comparison principle and the cone-valued Lyapunov function methods. Also, based on an extended comparison principle, a perturbation theory of switched stochastic systems is given.

关键词： Stochastic nonlinear system Practical φ0-stability Comparison principle Lyapunov function Perturbed system