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Journal of Ocean University of China 2017年第5期16卷 814-822页

作者： TANG Hao hu fuxiang XU Liuxiong DONG Shuchuang ZHOU Cheng WANG Xuefang College of Marine Sciences Shanghai Ocean University Shanghai 201306 P. R. China Faculty of Marine Science Tokyo University of Marine Science and Technology Minato Tokyo 108-8477 Japan National Engineering Research Center for Oceanic Fisheries Shanghai 201306 P. R. China Shanghai Collaborative Innovation Center for Oceanic Fisheries Shanghai 201306 P. R. China College of Fisheries Zhejiang Ocean University Zhoushan 316000 P. R. China

Knotless polyethylene(PE) netting has been widely used in aquaculture cages and fishing gears, especially in Japan. In this study, the hydrodynamic coefficient of six knotless PE netting panels with different solidity ratios were assessed in a flume tank under various attack angles of netting from 0?(parallel to flow) to 90?(perpendicular to flow) and current speeds from 40 cm s^(-1) to 130 cm s^(-1). It was found that the drag coefficient was related to Reynolds number, solidity ratio and attack angle of netting. The solidity ratio was positively related with drag coefficient for netting panel perpendicular to flow, whereas when setting the netting panel parallel to the flow the opposite result was obtained. For netting panels placed at an angle to the flow, the lift coefficient reached the maximum at an attack angle of 50? and then decreased as the attack angle further increased. The solidity ratio had a dual influence on drag coefficient of inclined netting panels. Compared to result in the literature, the normal drag coefficient of knotless PE netting measured in this study is larger than that of nylon netting or Dyneema netting.

关键词： panel fishing hydrodynamic Reynolds nylon polyethylene perpendicular Angle assessed aquaculture

Experimental and Numerical Investigations of the Hydrodynamic Characteristics, Twine Deformation, and Flow Field Around the Netting Structure Composed of Two Types of Twine Materials for Midwater Trawls

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Journal of Ocean University of China 2021年第5期20卷 1215-1235页

作者： THIERRY Bruno Nyatchouba Nsangue TANG Hao ACHILE Njomoue Pandong XU Liuxiong ZHOU Cheng hu fuxiang College of Marine Sciences Shanghai Ocean UniversityShanghai 201306China National Engineering Research Center for Oceanic Fisheries Shanghai 201306China Key Laboratory of Oceanic Fisheries Exploration Ministry of Agriculture and Rural AffairsShanghai 201306China The Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources Ministry of EducationShanghai Ocean UniversityShanghai 201306China Scientific Observing and Experimental Station of Oceanic Fishery Resources Ministry of Agriculture and Rural AffairsShanghai 201306China Laboratory E3M National High Polytechnic School of DoualaUniversity of DoualaDouala 2701Cameroon Faculty of Marine Science Tokyo University of Marine Science and TechnologyMinatoTokyo 108-8477Japan

Nettings are complex flexible structures used in various *** the hydrodynamic characteristics,de-formation,and the flow field around nettings is important to design successful fishing *** study investigated the hydrodynamic characteristics and deformation of five nettings made of polyethylene and nylon materials in different attack angles through numeri-cal simulation and physical model *** numerical model was based on the one-way coupling between computational fluid dynamics(CFD)and large deflection nonlinear structural ***-Stokes equations were solved using the finite volume ap-proach,the flow was described using the k-ωshear stress turbulent model,and the large deflection structural dynamic equation was derived using a finite element approach to understand the netting deformation and nodal *** porous media model was chosen to model the nettings in the CFD *** data were compared with the experimental results of the physical model to validate the numerical *** showed that the numerical data were compatible with the experimental data with an average relative error of 2.34%,3.40%,6.50%,and 5.80%in the normal drag coefficients,parallel drag coefficients,inclined drag coefficients,and inclined lift coefficients,*** hydrodynamic forces of the polyethylene and nylon nettings decreased by approxi-mately 52.56%and 66.66%,respectively,with decreasing net *** drag and lift coefficients of the nylon netting were appro-ximately 17.15%and 6.72%lower than those of the polyethylene netting.A spatial development of turbulent flow occurred around the netting because of the netting ***,the flow velocity reduction downstream from the netting in the wake region in-creased with increasing attack angle and net *** addition,the deformation,stress,and strain on each netting increased with in-creasing solidity ratio.

关键词： netting k-ωshear stress turbulent(SST)model porous media model large deflection nonlinear structural model hydrodynamic characteristics

Identifying the turbulent flow developing inside and around the bottom trawl by Electromagnetic Current Velocity Meter approach in the flume tank

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Journal of Hydrodynamics 2021年第3期33卷 636-656页

作者： Nyatchouba Nsangue Bruno Thierry Hao Tang Liu-xiong Xu fuxiang hu Xinxing You Micah Adekunle David Njomoue Pandong Achille College of Marine Sciences Shanghai Ocean UniversityShanghai201306China National Engineering Research Center for Oceanic Fisheries Shanghai201306China Key Laboratory of Oceanic Fisheries Exploration Ministry of Agriculture and Rural AffairsShanghai201306China The Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources Shanghai Ocean UniversityMinistry of EducationShanghai201306China Scientific Observing and Experimental Station of Oceanic Fishery Resources Ministry of Agriculture and Rural AffairsShanghai201306China Department of Marine Biosciences Tokyo University of Marine Science and TechnologyMinatoTokyoJapan College of Fisheries and Life Sciences Shanghai Ocean UniversityShanghai201306China Faculty of Industrial Engineering University of DoualaDoualaCameroon

The Knowledge of turbulent flow developing inside and around the bottom trawl net is of great importance not only for improving the hydrodynamic performance of the gear but also for the selectivity via the fish response,such as the herding response or escape *** 3-D Electromagnetic Current Velocity Meter(ECVM)measurements were performed to investigate the effect of turbulent flow on the bottom trawl net performance and to analyze the turbulence intensity and velocity ratio inside and around different parts of the trawl *** orthogonal decomposition(POD)method was applied in order to extract the phase averaged mean velocity field of turbulent flow from each available ECVM instantaneous *** results demonstrated the existence of turbulence flow,consisting of turbulent boundary layer flow and the turbulence due to the trawl wake developing all inside and around the bottom trawl *** input streamwise velocity results in faster trawl movement and a significant turbulent *** maximum turbulence intensity inside and around trawl wing,square part,first belly,second belly,third belly,cod-end is 0.95%,1.34%,3.40%,4.10%,4.25%and 3.80%,*** was found that the mean velocity field in a turbulent flow inside and around trawl net cod-end recovered on the average was~77.58%of the input streamwise *** is~12.92%,~13.07%,~11.40%,~13.00%and~0.45%less than that inside and around trawl wing,square part,first belly,second belly,and third belly of the bottom trawl net,*** turbulent flow behavior depends strongly on the structure oscillation,input streamwise velocity and,porosity of the net *** is necessary to take into account the velocity reduction inside and around a different part of the trawl net to improve the entire drag force determination,cod-end design,and further selectivity control of the fishing gear.

关键词： Hydrodynamic bottom trawl net turbulent flow Electromagnetic Current Velocity Meter(ECVM) turbulence intensity proper orthogonal decomposition(POD)

A newly developed soft-type turtle releasing device(Soft-TRD)for setnet fisheries

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Aquaculture and Fisheries 2021年第4期6卷 359-366页

作者： Daisuke Shiode Maika Shiozawa fuxiang hu Tadashi Tokai Yoshio Hirai Tokyo University of Marine Science and Technology MinatoTokyo108-8477Japan NITTO SEIMO Co. LTD.MinatoTokyo105-0004Japan

This study investigated a newly developed soft-type turtle releasing device(Soft-TRD)for *** setnet fish chambers(bag nets)are open at the sea surface,while others are closed(with ceiling netting)and *** turtles that stray into submerged bag nets often drown because the ceiling netting prevents them from swimming up to the surface to *** Soft-TRD has a slit that functions as an escape outlet at the center of a 2 m×2 m *** escape slit remains closed,due to the buoyancy of a float attached at each end of the slit,and prevents fish from getting *** can push the escape slit upward,which opens and allows the turtles to *** decide the optimum design of the Soft-TRD,a turtle releasing trial was conducted in an outdoor water *** loggerhead turtles(Caretta caretta)(standard carapace length(SCL):67.1-72.8 cm)and five green turtles(Chelonia mydas)(SCL:42.4-63.4 cm)were used for the trial.A single turtle was placed into the experimental bag net where the Soft-TRD(six models in total)was mounted at the center part of the ceiling,and its behavior was *** turtles successfully escaped the model with a 150 cm length escape slit,10 cm overlaying width,and a 4 kgf buoyancy float at each *** escape slit immediately closed after the turtles escaped.A sea trial(same model)was also performed using a submerged bag net(30×10×10 m)for two *** 90%(seven of the eight)of the entrapped loggerhead turtles successfully escaped out through the *** was not interrupted by the introduction of this *** use of the Soft-TRD would be helpful in releasing sea turtles from the setnets and contribute to sea turtle conservation efforts.

关键词： Bycatch Push-up Setnet Soft-TRD Turtle releasing device Turtle releasing system

Revealing the Fluttering Motions of Mid-Water Trawl Codend Through Sea Trials:Case Study of Antarctic Krill Trawl Codend

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Journal of Ocean University of China 2023年第2期22卷 555-564页

作者： LIU Wei TANG Hao NYATCHOUBA NSANGUE Bruno Thierry ZHANG Feng YIN Liqiang XU Liuxiong hu fuxiang LIU Pengfei College of Marine Sciences Shanghai Ocean UniversityShanghai 201306China National Engineering Research Center for Oceanic Fisheries Shanghai 201306China Key Laboratory of Oceanic Fisheries Exploration Ministry of Agriculture and Rural AffairsShanghai 201306China The Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources Shanghai Ocean UniversityMinistry of EducationShanghai 201306China Scientific Observing and Experimental Station of Oceanic Fishery Resources Ministry of Agriculture and Rural AffairsShanghai 201306China Faculty of Marine Science Tokyo University of Marine Science and TechnologyMinatoTokyo 108-8477Japan Tendering Office Shanghai Ocean UniversityShanghai 201306China

The dynamic coupling between the fluttering motions and hydrodynamic characteristics of codend is essential in understanding the trawl selectivity through fish response and the drag force acting on the whole *** study investigated the effect of towing speed,warp length,warp tension,and catch size on the fluttering motions of Antarctic krill trawl codend during net shooting,towing,and hauling by using sea trial *** time-periodicity of codend oscillation was analyzed by the Morlet wavelet transform *** indicated that the period of codend oscillation was between 50 s and 90 s and showed an increasing trend with the warp tension but a decreased value at the towing *** coefficient amplitude of codend oscillation was between 0 and 4 at the net shooting and hauling stages,and between 0.2 and 0.6 at the towing *** amplitude of codend oscillation increased with the warp tension,towing speed,and catch size,but decreased with the increase of the warp *** addition,the period of codend oscillation increased with the towing speed at the net shooting and hauling stages,but decreased at the towing *** results from codend fluttering motions can improve the understanding of fish behavior and gear shape that modify the hydrodynamic force on the codend instantaneously.

关键词： codend fluttering motions sea trials Morlet wavelet periodicity

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多目标模糊决策在台阶高度优化中的应用

金属矿山 2000年第4期29卷 20-22,34页

作者：胡福祥马鞍山矿山研究院

针对多个评价指标的矿山开采工艺参数确定问题 ,进行了多目标模糊决策方法在露天矿台阶高度优化中的应用研究 ,应用结果表明。

关键词：露天矿台阶高度多目标模糊决策最佳化

The deformation characteristics and flow field around knotless polyethylene netting based on fluid structure interaction(FSI)one-way coupling

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Aquaculture and Fisheries 2022年第1期7卷 89-102页

作者： Baiqiang Zou Nyatchouba Nsangue Bruno Thierry Hao Tang Liuxiong Xu Shuchuang Dong fuxiang hu College of Marine Sciences Shanghai Ocean UniversityShanghai201306PR China National Engineering Research Center for Oceanic Fisheries Shanghai201306PR China Key Laboratory of Oceanic Fisheries Exploration Ministry of Agriculture and Rural AffairsShanghai201306China The Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources Shanghai Ocean UniversityMinistry of EducationShanghai201306China Scientific Observing and Experimental Station of Oceanic Fishery Resources Ministry of Agriculture and Rural AffairsShanghai201306China Institute of Industrial Science The University of Tokyo5-1-5 KashiwanohaKashiwaChiba277-8574Japan Faculty of Marine Science Tokyo University of Marine Science and TechnologyMinatoTokyo108-8477Japan

Knotless polyethylene(PE)netting is widely used in fisheries because of its excellent hydrodynamic performance and low *** deformation and the surrounding flow field distribution play an important role in determining the hydrodynamic characteristics of netting in moving *** order to investigate the effect of solidity ratio and attack angle on drag,netting deformation,and flow field distribution through the netting,a fluid-structure interaction(FSI)model based on a one-way coupling combining the shear stress turbulent(SST)k-omega model and the large deformation nonlinear structural finite element model was *** results showed the difference between the parallel and normal drag forces found in the present numerical model and experimental flume tank data were 9.17%and 11.58%,*** mean relative error in the inclined hydrodynamic drag for different flow velocities and attack angles was 8.35%,6.69%,and 5.37%for the nettings 1,2,and 3,*** results show that the present numerical simulation based on FSI one-way coupling can be used to examine hydrodynamic forces on *** flow simulation results show that there is a noticeable flow velocity decrease through the netting and a rather large velocity reduction region downstream from the netting for different attack *** results reveal the existence of turbulent flow due to the netting *** was found that the equivalent stress and total deformation increase as the flow velocity increases and solidity ratio decreases.

关键词： Knotless netting Fluid structure interaction Deformation characteristics Flow field SST k-omega model

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信息化导向的高职未来课堂探讨与设计

中国职业技术教育 2019年第30期35卷 14-19页

作者：胡伏湘长沙商贸旅游职业技术学院

将信息技术融入教育,构建未来课堂,推动课堂革命,这是国家的要求,更是学习者的期盼。从有关文件着手,系统梳理了国内外未来课堂主题所取得的阶段性成果,探讨了未来课堂所涵盖的七个关键内容,研究了信息化导向的未来课堂的特征、建设目... 详细信息

将信息技术融入教育,构建未来课堂,推动课堂革命,这是国家的要求,更是学习者的期盼。从有关文件着手,系统梳理了国内外未来课堂主题所取得的阶段性成果,探讨了未来课堂所涵盖的七个关键内容,研究了信息化导向的未来课堂的特征、建设目标与思路,并设计了包括数据采集和数据中心的信息化教学环境建设方案,提出了"双高计划"背景下实施未来课堂的四个阶段,为职业院校实施智慧教育提供借鉴和参考。

关键词：信息化未来课堂课堂革命双高计划智慧教育

Experimental investigation of hydrodynamic characteristics of tuna purse seine netting panels with different knot types in uniform flow

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Experimental investigation of hydrodynamic characteristics o...

2016年中国水产学会学术年会

作者： Hao Tang Liuxiong Xu fuxiang hu College of Marine Sciences Shanghai Ocean University National Engineering Research Center for Oceanic Fisheries Faculty of Marine Science Tokyo University of Marine Science and Technology

Nylon netting is widely used in purse seine and other fishing gears due to its excellent physical characteristics with high strength and better sinking *** study aims to investigate hydrodynamic characteristics of nylon netting at various attack angles and current speeds,and to quantify the difference in the hydrodynamic coefficients between different netting panels with different knot types and twine *** was found that the hydrodynamic coefficients was related to Reynolds number,solidity ratio,attack angle,knot type and twine *** solidity ratio was positively correlated with normal drag coefficient,whereas it is contrary in the dependence of the parallel drag *** netting panel inclined to the current,the solidity ratio had a dual influence on drag coefficient;the lift coefficient reached the culminating point at an attack angle of 50°and subsequently decreased as increased attack angle *** found that the drag coefficient generated by knot accounted for 15-25%of total drag coefficient,the knotted netting with higher solidity ratio exhibits a greater parallel drag coefficient,opposite to results of knotless *** to knotless PE netting,the drag coefficients of knotless PA netting were dominant at higher Reynolds number（Re＞2200）.

关键词： Nylon netting Solidity ratio Drag coefficient Lift coefficient Knot type

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基于XML的分布式防火墙异常规则发现算法

计算机应用与软件 2008年第11期25卷 261-264页

作者：胡伏湘中南林业科技大学环艺学院湖南长沙410004 长沙民政学院软件学院湖南长沙410004

分析了分布式防火墙(DFW)规则异常产生的原因,定义了规则的四种相关性:完全无关、完全匹配、包含匹配、部分相关,然后对四种类型规则异常进行了规范的定义,包括阴影异常、虚假异常、冗余异常和关联异常,并运用基于XML的规则模型设计了基... 详细信息

分析了分布式防火墙(DFW)规则异常产生的原因,定义了规则的四种相关性:完全无关、完全匹配、包含匹配、部分相关,然后对四种类型规则异常进行了规范的定义,包括阴影异常、虚假异常、冗余异常和关联异常,并运用基于XML的规则模型设计了基于XML的异常规则发现算法。通过FPA软件实现了本算法,对查全率和性能进行了分析。

关键词： DFW 策略管理 XML 异常规则算法设计