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基于CFD方法的无人潜水器运动特性分析

中国造船 2024年第1期65卷 213-222页

作者：郭佳奇李鹏秦洪德林忠宇哈尔滨工程大学水下机器人技术国家重点实验室哈尔滨150001 哈尔滨工程大学烟台研究院烟台264006

以经典的SUBOFF潜艇模型为研究对象,运用商业软件STAR-CCM+收集和分析该艇的速度信息,计算作用在艇体上的水动力。分别进行了斜航运动与纯横荡、纯摇艏运动仿真,求取相应的水动力系数。给出在4.5kn与6.5kn航速下的斜航模拟试验中模型所... 详细信息

以经典的SUBOFF潜艇模型为研究对象,运用商业软件STAR-CCM+收集和分析该艇的速度信息,计算作用在艇体上的水动力。分别进行了斜航运动与纯横荡、纯摇艏运动仿真,求取相应的水动力系数。给出在4.5kn与6.5kn航速下的斜航模拟试验中模型所受的垂向力与摇艏力矩,对它们与速度的关系进行拟合,计算相应的水动力系数。对模型进行纯横荡与纯摇艏数值模拟,通过拟合曲线求得相应的水动力系数。该研究对进一步研究无人潜水器水动力性能和运动控制具有重要参考意义。

关键词：水动力系数 SUBOFF 水动力性能 CFD

A Free Surface Frequency Domain Green Function with Viscous Dissipation and Partial Reflections from Side Walls

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Journal of Marine Science and Application 2011年第3期10卷 259-264页

作者： hongde qin Jing Shen Xiaobo Chen College of Shipbuilding Engineering Harbin Engineering University Harbin 150001 China Research Department Bureau Veritas 925 70 Neuilly-Sur-Seine France

The free-surface Green function method is widely used in solving the radiation or diffraction problems caused by a ship or ocean structure oscillating on the waves. In the context of inviscid potential flow, hydrodynamic problems such as multi-body interaction and tank side wall effect cannot be properly dealt with based on the traditional free-surface frequency domain Green function method, in which the water viscosity is omitted and the energy dissipation effect is absent. In this paper, an open-sea Green function with viscous dissipation was presented within the theory ofvisco-potential flow. Then the tank Green function with a partial reflection from the side walls in wave tanks was formulated as a formal sum of open-sea Green functions representing the infinite images between two parallel side walls of the source in the tank. The new far-field characteristics of the tank Green function is vitally important fur improving the validity of side-wall effects evaluation, which can be used in supervising the tank model tests.

关键词： Green function viscous dissipation side wall effect partial reflection

迪北区块深层致密砂岩气藏氮气钻完井技术应用及认识

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钻采工艺 2024年第1期47卷 16-23页

作者：王春生冯少波龙敏李宁梁红军张权秦宏德滕志想中国石油塔里木油田公司新疆维吾尔自治区841000

针对塔里木油田迪北区块目的层阿合组致密砂岩储层岩性致密、地层压力高、煤层发育,应用常规液体介质的钻完井技术对储层损害严重,为此特引入氮气钻完井技术,并在DX1井开展现场试验,获得日产气量82.39×104m3,日产油量100.8 m3的高产。... 详细信息

针对塔里木油田迪北区块目的层阿合组致密砂岩储层岩性致密、地层压力高、煤层发育,应用常规液体介质的钻完井技术对储层损害严重,为此特引入氮气钻完井技术,并在DX1井开展现场试验,获得日产气量82.39×104m3,日产油量100.8 m3的高产。但由于地层岩性的复杂性,氮气钻完井过程中,出现了井壁垮塌严重、内防喷工具失效、井控装备冲蚀等问题,制约了氮气钻完井技术在该区块的推广应用。通过对井身结构、钻具组合、井口装备、排砂管线、内防喷工具以及配套工艺流程等关键工艺、装备的改进优化,形成适用于高压高产深层致密砂岩储层的氮气钻完井配套工艺技术,并在DB104井开展了现场试验,试验效果显著。与同区块液体介质钻井的钻完井方式相比,DB104井日产气增加了400余倍,日产油量增加了6倍。通过DX1井和DB104井证明,只要工艺、装备、措施得当,氮气钻完井技术在迪北区块这类高温高压深层致密砂岩气藏中对储层具有重要的保护作用,可为塔里木油田乃至全国高压高产致密砂岩储层的高效勘探开发提供技术支撑。

关键词：迪北区块高压高产深层致密气藏氮气钻完井储层保护

A Motion Simulation of Bionic Jellyfish Based on Shape Memory Alloy

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A Motion Simulation of Bionic Jellyfish Based on Shape Memor...

Analysis of short fruiting branch gene and Marker-assisted selection with SNP linked to its trait in upland cotton

第36届中国控制会议

作者： Zhuo Wang Xiyuan Lin Xiaoning Feng hongde qin Shenfang Xu Science and Technology on Underwater Vehicle Laboratory Harbin Engineering University College of computer Science and Technology Harbin Engineering University

ISBN: (纸本)9781538629185

Based on the research object of jellyfish,a kind of bionic jellyfish robot driven by shape memory alloy was designed,which could imitate the jet propulsion of the ***,the propulsion mode and morphological characteristics of jellyfish are ***,the characteristics of shape memory alloy sre studied,and the structure for the six leg drive based on shape memory alloy is *** driving methods of the shape memory alloy are researched and ***,the motion model for jellyfish is *** with the bell volume of jellyfish change,the movement numerical simulation of the jellyfish results are obtained through *** with three different groups of jellyfish parameters,through motion simulation of jellyfish,the optimal size is selected.

关键词： Bionic jellyfish Shape memory alloy Motion simulation

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Journal of Cotton Research 2018年第1期1卷 20-26页

作者： ZHANG Youchang FENG Changhui BIE Shu WANG Xiaogang ZHANG Jiaohai XIA Songbo qin hongde Institute of Cash Crops Hubei Academy of Agricultural Sciences Key Laboratory of Cotton Biology and Breeding in the Middle Reaches of the Yangtze River (Wuhan) Ministry of Agriculture

Background： With the rapid development of genomics, many functional genes have been targeted. Molecular marker assisted selection can accelerate the breeding process by linking selection to functional genes. Methods： In a study of upland cotton （Gossypium hirsutum L.）, the F2 segregated population was constructed by crossing X1570 （short branches） with Ekangmian 13 （long branches） to identify the short fruiting branch gene and marker assisted selection with SNP（Single Nucleotide Polymorphisms, SNP） linked to its trait. Result： The result demonstrated that linked SSR marker BNL3232 was screened by BSA（Bulked segregant analysis, BSA） method; one SNP locus was found, which was totally separated from the fruiting branches trait in upland cotton. Conclusion： It was verified that this SNP marker could be used for molecular assisted selection of cotton architecture

关键词： Short fruit branch Cotton Gene Marker assisted selection

Study on the Design Method of the Jack-up＇s X-Type Cantilever Allowable Load Nephogram

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Journal of Marine Science and Application 2014年第3期13卷 315-320页

作者： Yazhou Zhu Chengmeng Sun hongde qin Bin Jiang Yansong Fan College of Shipbuilding Engineering Harbin Engineering University Harbin 150001 China Offshore Engineering Equipment Research Institute Bohai Equipment Manufacturing Co. Ltd. China National Petroleum Corporation(CNPC) Panjin 124010 China

The extending of a cantilever and transverse moving of a drilling floor enable the jack-up to operate in several well positions after the Jack-up has pitched. The cantilever allowable load nephogram is the critical reference which can evaluate the jack-up's drilling ability, design the cantilever structure and instruct a jack-up manager to make the operations safe. The intent of this paper is to explore the interrelationships between the cantilever position, drilling floor and the loads including wind force, the stand set-back weight etc., through analyzing the structure and load characteristics of the x-type cantilever and the simplified mechanics model with the restriction of the maximum moment capacity of the cantilever single side beam. Referring to several typical position designs load values, the cantilever allowable load nephogram is obtained by using the suitable interpolation method. The paper gives a method for cantilever allowable load design, which is proved reliable and effective by the calculation example.

关键词： jack-up cantilever expand cantilever allowable loadnephogram drilling ability x-type cantilever

Mechatronic Design and Maneuverability Analysis of a Novel Robotic Shark

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Journal of Marine Science and Application 2022年第2期21卷 82-91页

作者： Liyang Gao Peng Li hongde qin Zhongchao Deng College of Shipbuilding Engineering Harbin Engineering UniversityHarbin 150001China Yantai Research Institute and Graduate School of Harbin Engineering University Yantai 264006China

In this paper,the mechatronic design and maneuverability analysis of a novel robotic shark are *** obtain good maneuverability,a barycenter regulating device is designed to assist the posture adjustment at low *** on the Newton-Euler approach,an analytical dynamic model is established with particular consideration of pectoral fins for threedimensional *** hydrodynamic coefficients are computed using computational fluid dynamics(CFD)*** amplitudes and phases are determined by fitting an optimized fish body *** performance of the robotic shark is estimated by varying the oscillation frequency and offset *** results show that with oscillation frequency increasing,the swimming speed increases *** robotic shark reaches the maximum swimming speed of 1.05 m/s with an oscillation frequency of 1.2 ***,the turning radius decreases nonlinearly as the offset angle *** robotic shark reaches the minimum turning radius of 1.4 times the body length with 0.2 Hz frequency and 12°offset *** the vertical plane,as the pectoral fin angle increases,the diving velocity increases nonlinearly with increase rate slowing down.

关键词： Mechatronic design Three-joint propulsion system Robotic shark Dynamic modeling Maneuverability analysis

Cloning and Expression Analysis of Chalcone Synthase and Chalcone Isomerase Encoding Genes in Gossypium hirsutum

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Agricultural Biotechnology 2018年第2期7卷 15-21,26页

作者： Chengpan SONG Songbo XIA Xiaogang WANG Jiaohai ZHANG hongde qin Youchang ZHANG Changhui FENG Shu BIE College of Life Sciences Wuhan UniversityWuhan 430000China Institute of Cash Crops Hubei Academy of Agricultural SciencesWuhan 430000China Key Laboratory of Cotton Biology and Breeding in the Middle Reaches of the Changjiang River Ministry of AgricultureWuhan 430064China

In this study,chalcone synthase and chalcone isomerase encoding genes(GhCHS and GhCHI)were cloned from upland cotton(Gossypium hirsutum)cultivar HM-40,and analyzed *** functions were analyzed through virus induced gene silencing(VIGS).The results showed that GhCHS gene has an open reading frame(ORF)of 1170 bp and encodes a protein of 389 amino *** phosphorylation sites were detected in GhCHS protein,suggesting that it may be involved in kinase *** deduced GhCHS protein was most closely related to Theobroma cacao CHS protein according to phylogenetic *** GhCHI ORF was 630 bp and encoded a protein of 209 amino *** phosphorylation sites were found in GhCHI protein,indicating that it may be related to kinase *** GhCHI protein was most closely related to Hibiscus cannabinus CHI protein according to phylogenetic *** PCR(q PCR)showed that GhCHS and GhCHI were rapidly activated after inoculation with Verticillium dahliae VD07,and then their expression levels kept increasing over time,indicating that the two genes might play an important role in the defense response against Verticillium *** induced gene silencing(VIGS)was used to silence endogenous GhCHS and GhCHI genes in upland cotton plants before VD07 was inoculated to identify disease *** results showed that the disease index of plants untreated with Agrobacterium tumefaciens was 31.2,and that of the plants inoculated with empty vector was *** disease index of GhCHS-silenced plants was 72.5,and that in GhCHI-silenced plants was *** results confirmed that GhCHS and GhCHI may play an important role in defense response of upland cotton to Verticillium wilt.

关键词： Upland cotton(Gossypium hirsutum L.) Grafting GhCHS GhCHI Verticillium wilt VIGSHome

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一种水下双目视觉测距方法研究

华中科技大学学报（自然科学版） 2018年第8期46卷 93-98页

作者：盛明伟周浩黄海秦洪德哈尔滨工程大学水下机器人重点实验室

基于改进的SIFT特征匹配算法,建立了一个水下双目视觉测距系统.围绕提高水下双目视觉测距的精度、速度和抗干扰度等,研究了图像预处理、SIFT特征匹配算法等关键技术.针对传统图像直方图均衡化结果过亮或过暗现象以及过增强的特点,提出... 详细信息

基于改进的SIFT特征匹配算法,建立了一个水下双目视觉测距系统.围绕提高水下双目视觉测距的精度、速度和抗干扰度等,研究了图像预处理、SIFT特征匹配算法等关键技术.针对传统图像直方图均衡化结果过亮或过暗现象以及过增强的特点,提出了一种改进的结合了OTSU阈值算法的直方图均衡化方法;结合稀疏匹配搜索算法,提出一种改进的SIFT特征匹配算法对左、右目图像进行特征匹配.利用区域增长算法,分别生成了水下标定板和机械臂的伪彩色视差图像,由视差图获得了目标相应位置的距离.实验结果显示：水下标定板平均测距精确度为97.66%,利用所提方法也获得了水下机械臂的双目视差图像.

关键词：图像处理双目视觉测距方法水下双目视觉特征匹配视差图像