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An Integrated Hydrodynamics and Control Model of A Tethered Underwater Robot

China Ocean Engineering 2018年第5期32卷 557-569页

作者： WU Jia-ming XU ying TAO Long-bin YU Miao dou yi-zhe Department of Naval Architecture and Ocean Engineering School of Civil Engineering and TransportationSouth China University of Technology Department of Naval Architecture Ocean & Marine EngineeringUniversity of Strathclyde

An integrated hydrodynamics and control model to simulate tethered underwater robot system is proposed. The governing equation of the umbilical cable is based on a finite difference method, the hydrodynamic behaviors of the underwater robot are described by the six-degrees-of-freedom equations of motion for submarine simulations, and a controller based on the fuzzy sliding mode control(FSMC) algorithm is also incorporated. Fluid motion around the main body of moving robot with running control ducted propellers is governed by the Navier–Stokes equations and these nonlinear differential equations are solved numerically via computational fluid dynamics(CFD) technique. The hydrodynamics and control behaviors of the tethered underwater robot under certain designated trajectory and attitude control manipulation are then investigated based on the established hydrodynamics and control model. The results indicate that satisfactory control effect can be achieved and hydrodynamic behavior under the control operation can be observed with the model; much kinematic and dynamic information about tethered underwater robot system can be forecasted, including translational and angular motions of the robot, hydrodynamic loading on the robot, manipulation actions produced by the control propellers, the kinematic and dynamic behaviors of the umbilical cable. Since these hydrodynamic effects are fed into the proposed coupled model, the mutual hydrodynamic influences of different portions of the robot system as well as the hydrological factors of the undersea environment for the robot operation are incorporated in the model.

关键词： tethered underwater robot umbilical cable ducted propeller fuzzy sliding mode control CFD trajectory and attitude control

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水下潜器系统导管螺旋桨水动力特性及周围流场分布预报与分析

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船舶力学 2018年第5期22卷 540-551页

作者：吴家鸣赖宇锋李江伟窦义哲陈东军华南理工大学土木与交通学院广州510640

运用计算流体力学方法对水下潜器系统中导管螺旋桨在水下潜器转艏运动中螺旋桨周围的水动力现象进行观察,对在这样的工况下导管螺旋桨周围流场特征、进速、诱导速度、推力沿盘面和桨叶径向的分布,以及螺旋桨所发出的推力与螺旋桨周围流... 详细信息

运用计算流体力学方法对水下潜器系统中导管螺旋桨在水下潜器转艏运动中螺旋桨周围的水动力现象进行观察,对在这样的工况下导管螺旋桨周围流场特征、进速、诱导速度、推力沿盘面和桨叶径向的分布,以及螺旋桨所发出的推力与螺旋桨周围流场之间的关系进行观察。计算结果表明:在一定的螺旋桨转速条件下,进速越小,螺旋桨所发出的推力也越大;由于导管出口处激发出的梢泄涡作用,导致盘面后叶梢附近轴向诱导速度降低、压力增大,该处叶面与叶背之间的压差也随之增大;螺旋桨的推力沿桨叶径向的分布呈现出半径越大,所产生的推力也越大的特点。

关键词：导管螺旋桨计算流体力学水下潜器推力进速诱导速度

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40m游艇艇艏砰击压力有限元分析

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集美大学学报（自然科学版） 2014年第6期19卷 442-445页

作者：窦义哲陈章兰集美大学轮机工程学院福建厦门361021

为了研究艇艏横倾时的砰击状况,采用数值模拟的方法对一艘长40 m钢制游艇的艇艏砰击性能进行了分析.在验证有限元方法模拟船舶入水砰击的基础上,利用ANSYS/LS-DYNA软件建立船艏二维有限元模型,分析了游艇不同入水速度和横倾角对艇艏砰... 详细信息

为了研究艇艏横倾时的砰击状况,采用数值模拟的方法对一艘长40 m钢制游艇的艇艏砰击性能进行了分析.在验证有限元方法模拟船舶入水砰击的基础上,利用ANSYS/LS-DYNA软件建立船艏二维有限元模型,分析了游艇不同入水速度和横倾角对艇艏砰击压力的影响规律,数值模拟结果为预报艇艏的砰击压力状况提供依据,为游艇的结构设计提供参考价值.

关键词：艇艏砰击压力二维有限元

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Effects of Bifidobacterium lactis BLa80 on fecal and mucosal flora and stem cell factor/c-kit signaling pathway in simulated microgravity rats

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World Journal of Gastroenterology 2025年第1期31卷 93-109页

作者： Ping Zhang ying Zhu Pu Chen Tong Zhou zhe-yi Han Jun Xiao Jian-Feng Ma Wen Ma Peng Zang ying Chen Graduate School Hebei North UniversityZhangjiakou 075000Hebei ProvinceChina Key Laboratory of Aerospace Nutrition and Food Engineering China Astronaut Research and Training CenterBeijing 100094China Department of Gastroenterology The Air Force Medical CenterBeijing 100142China Department of Blood Transfusion Air Force Medical CenterBeijing 100142China

BACKGROUND Simulated microgravity environment can lead to gastrointestinal motility *** pathogenesis of gastrointestinal motility disorders is closely related to the stem cell factor(SCF)/c-kit signaling pathway associated with intestinal flora and Cajal stromal ***,intestinal flora can also affect the regulation of SCF/c-kit signaling pathway,thus affecting the expression of Cajal stromal *** cells are the pacemakers of gastrointestinal *** To investigate the effects of Bifidobacterium lactis(***)BLa80 on the intestinal flora of rats in simulated microgravity and on the gastrointestinal motility-related SCF/c-kit *** The internationally recognized tail suspension animal model was used to simulate the microgravity environment,and 30 rats were randomly divided into control group,tail suspension group and drug administration tail suspension group with 10 rats in each group for a total of 28 *** tail group was given *** BLa80 by intragastric administration,and the other two groups were given water intragastric administration,the concentration of intragastric administration was 0.1 g/mL,and each rat was 1 mL/***&eosin staining was used to observe the histopathological changes in each segment of the intestine of each group,and the expression levels of SCF,c-kit,extracellular signal-regulated kinase(ERK)and p-ERK in the gastric antrum of each group were detected by Western blotting and *** fecal flora and mucosal flora of rats in each group were detected by 16S *** Simulated microgravity resulted in severe exfoliation of villi of duodenum,jejunum and ileum in rats,marked damage,increased space between villi,loose arrangement,shortened columnar epithelium of colon,less folds,narrower mucosal thickness,reduced goblet cell number and crypts,and significant improvement after probiotic *** microgravity reduced the expressions of SCF and c-kit,and increased the express

关键词： Simulated microgravity Rat Intestinal flora Gastrointestinal motility Stem cell factor/c-kit signaling pathway

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导管剖面设计对导管螺旋桨水动力特性的影响

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舰船科学技术 2017年第11期39卷 38-43页

作者：吴家鸣廖贯宇赖宇锋窦义哲陈东军华南理工大学土木与交通学院广东广州510640

运用计算流体的方法对导管螺旋桨的叶梢漩涡、螺旋桨周围流场和推力特性进行计算,并且通过组合不同类型的导管对比分析了梢涡的改善方法和推力性能的优化方案。计算结果表明:调整导管螺旋桨中的导管迎角,并延长导管有助于改善导管螺旋... 详细信息

运用计算流体的方法对导管螺旋桨的叶梢漩涡、螺旋桨周围流场和推力特性进行计算,并且通过组合不同类型的导管对比分析了梢涡的改善方法和推力性能的优化方案。计算结果表明:调整导管螺旋桨中的导管迎角,并延长导管有助于改善导管螺旋桨梢涡的产生和改善桨毂后的尾流,有利于提高导管螺旋桨的稳定性;增大导管迎角并延长导管能够使桨叶上荷载和推力分布更加均匀;在进速系数J=0.4左右,导管螺旋桨性能更优,也更高效。本文结论有助于设计出性能优良的导管螺旋桨。

关键词：导管螺旋桨计算流体力学梢涡导管水动力

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Bi-continuous Mg-Ti interpenetrating-phase composite as a partially degradable and bioactive implant material

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Journal of Materials Science & Technology 2023年第15期146卷 211-220页

作者： Chenxi dou Mingyang Zhang Dechun Ren Haibin Ji zhe yi Shaogang Wang Zengqian Liu Qiang Wang Yufeng zheng zhefeng Zhang Rui Yang Liaoning Provincial Key Laboratory of Oral Diseases School and Hospital of StomatologyChina Medical UniversityShenyang 110001China Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China School of Materials Science and Engineering Peking UniversityBeijing 100871China Center for Adaptive System Engineering School of Creativity and ArtShanghaiTech UniversityShanghai 201210China

Mg(and Mg alloys)and Ti(and Ti alloys)are two important classes of metallic implant materials which are respectively completely degradable and non-degradable after *** composites composed of them offers the promise for combining their property advantages for bone ***,we present a Mg-Ti composite fabricated by pressureless infiltration of pure Mg melt into 3D printed Ti scaffold,and demonstrate a potential of the composite for use as new partially degradable and bioactive implant *** composite has such architecture that the Mg and Ti phases are topologically bicontinuous and mutually interspersed in 3D space,and exhibits several advantages over its constituents,such as higher strengths than as-cast pure Mg and Ti scaffold along with lower Young’s modulus than dense ***,the degradation of Mg phase may induce the formation and ingrowth of new bone tissues into the Ti scaffold to form mechanical interlocking between them;in this process,the Ti scaffold provides constant support and Young’s modulus adaptively decreases toward that of *** the accelerated corrosion than pure Mg,the composite remains non-cytotoxic and does not cause obvious adverse reactions after implantation as revealed by in vitro and in vivo *** study may offer a new possibility for combining mechanical durability and bioactivity in implant materials,and allow for customized and targeted design of the implant.

关键词： Mg-Ti composite Interpenetrating-phase architecture Implant Bioactivity Degradation Strength

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To explore the mechanism of yigong San anti-gastric cancer and immune regulation

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1965-1994页

作者： dou-dou Lu Ling Yuan Zhao-Zhao Wang Jian-Jun Zhao Yu-Hua Du Na Ning Guo-Qing Chen Shi-Cong Huang yi Yang zhe Zhang yi Nan School of Clinical Medicine Ningxia Medical UniversityYinchuan 750004Ningxia Hui Autonomous RegionChina College of Pharmacy Ningxia Medical UniversityYinchuan 750004Ningxia Hui Autonomous RegionChina Traditional Chinese Medicine College Ningxia Medical UniversityYinchuan 750004Ningxia Hui Autonomous RegionChina Department of Chinese Medical Gastrointestinal China-Japan Friendship HospitalBeijing 100029China Key Laboratory of Ningxia Minority Medicine Modernization Ministry of Education Ningxia Medical UniversityYinchuan 750004Ningxia Hui Autonomous RegionChina

BACKGROUND yigong San(YGS)is a representative prescription for the treatment of digestive disorders,which has been used in clinic for more than 1000 ***,the mechanism of its anti-gastric cancer and regulate immunity are still remains *** To explore the mechanism of YGS anti-gastric cancer and immune *** Firstly,collect the active ingredients and targets of YGS,and the differentially expressed genes of gastric ***,constructed a protein-protein interaction network between the targets of drugs and diseases,and screened hub *** the clinical relevance,mutation and repair,tumor microenvironment and drug sensitivity of the hub gene were ***,molecular docking was used to verify the binding ability of YGS active ingredient and hub *** Firstly,obtained 55 common targets of gastric cancer and *** Kyoto Encyclopedia of Genes and Genomes screened the microtubule-associated protein kinase signaling axis as the key pathway and IL6,EGFR,MMP2,MMP9 and TGFB1 as the hub *** 5 hub genes were involved in gastric carcinogenesis,staging,typing and prognosis,and their mutations promote gastric cancer ***,molecular docking results confirmed that the components of YGS can effectively bind to therapeutic *** YGS has the effect of anti-gastric cancer and immune regulation.

关键词： Gastric cancer yigong San Mechanism Immune

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Cascading failures in local-world evolving networks

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Journal of zhejiang University-Science A(Applied Physics & Engineering) 2008年第10期9卷 1336-1340页

作者： zhe-jing BAO yi-jia CAO School of Electrical Engineering Zhejiang University Hangzhou 310027 China College of Electrical and Information Engineering Hunan University Changsha 410082 China

The local-world (LW) evolving network model shows a transition for the degree distribution between the exponential and power-law distributions, depending on the LW size. Cascading failures under intentional attacks in LW network models with different LW sizes were investigated using the cascading failures load model. We found that the LW size has a significant impact on the network's robustness against deliberate attacks. It is much easier to trigger cascading failures in LW evolving networks with a larger LW size. Therefore, to avoid cascading failures in real networks with local preferential attachment such as the Internet, the World Trade Web and the multi-agent system, the LW size should be as small as possible.

关键词： Complex network Local world (LW) Cascading failures Power-law Attack

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Influence of a multi-step process on the thickness reduction error of sheet metal in a flexible rolling process

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International Journal of Minerals,Metallurgy and Materials 2019年第1期26卷 76-85页

作者： yi Li Ming-zhe Li Kai Liu Dieless Forming Technology Center Roll Forging Institute Jilin University College of Materials Science and Engineering Jilin University

Flexible rolling is a forming process based on thickness reduction, and the precision of thickness reduction is the key factor affecting bending deformation. The major purpose of the present work is to solve the problem of bending deformation error caused by insufficient thickness reduction. Under the condition of different rolling reductions with the same sheet thickness and the same thickness reduction with different sheet thicknesses, the thickness reduction error of sheet metal is analyzed. In addition, the bending deformation of sheet metal under the same conditions is discussed and the influence of the multi-step forming process on the thickness reduction error is studied. The results show that, under the condition of the same sheet thickness, the thickness reduction error increases with increasing rolling reduction because of an increase in work hardening. As rolling reduction increases, the longitudinal bending deformation decreases because of the decrease of the maximum thickness difference. Under the condition with the same thickness reduction, the thickness reduction error increases because of the decrease of the rolling force with increasing sheet thickness. As the sheet thickness increases, the longitudinal bending deformation increases because of the increase in the maximum thickness difference. A larger bending deformation is divided into a number of small bending deformations in a multi-step forming process, avoiding a sharp increase in the degree of work hardening; the thickness reduction error is effectively reduced in the multi-step forming process. Numerical simulation results agree with the results of the forming experiments.

关键词： flexible rolling convex surface numerical simulation thickness reduction error multi-step forming process

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Hilbert genus fields of biquadratic fields

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Science China Mathematics 2014年第10期57卷 2111-2122页

作者： OUYANG yi ZHANG zhe School of Mathematical Sciences University of Science and Technology of China

The Hilbert genus field of the real biquadratic field K=Q（√δ,√d）is described by Yue（2010）and Bae and Yue（2011）explicitly in the case＆=2 or p with p=1 mod 4 a prime and d a squarefree positive *** this article,we describe explicitly the Hilbert genus field of the imaginary biquadratic field K=Q（√δ,√d）,whereδ=-1,-2 or-p with p=3 mod 4 a prime and d any squarefree *** completes the explicit construction of the Hilbert genus field of any biquadratic field which contains an imaginary quadratic subfield of odd class number.

关键词： class group Hilbert symbol Hilbert genus field

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