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Cooperative path planning for multi-AUV in time-varying ocean flows

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Journal of Systems Engineering and Electronics 2016年第3期27卷 612-618页

作者： mingyong liu Baogui Xu Xingguang Peng School of Marine Science and Technology Northwestern Polytechnical University

For low-speed underwater vehicles, the ocean currents has a great influence on them, and the changes in ocean currents is complex and continuous, thus whose impact must be taken into consideration in the path planning. There are still lack of authoritative indicator and method for the cooperating path planning. The calculation of the voyage time is a difficult problem in the time-varying ocean, for the existing methods of the cooperating path planning, the computation time will increase exponentially as the autonomous underwater vehicle（AUV） counts increase, rendering them unfeasible. A collaborative path planning method is presehted for multi-AUV under the influence of time-varying ocean currents based on the dynamic programming algorithm. Each AUV cooperates with the one who has the longest estimated time of sailing, enabling the arrays of AUV to get their common goal in the shortest time with minimum timedifference. At the same time, they could avoid the obstacles along the way to the target. Simulation results show that the proposed method has a promising applicability.

关键词： dynamic programming time-varying cooperate path planning autonomous underwater vehicle（AUV）

Sliding mode control and Lyapunov based guidance law with impact time constraints

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Journal of Systems Engineering and Electronics 2017年第6期28卷 1186-1192页

作者： Xiaojian Zhang mingyong liu Yang Li School of Marine Science and Technology Northwestern Polytechnical University Xi’an 710021 China

This paper analyses the issue of impact time control of super-cavitation weapons impact fixed targets which mainly refer to the ships or submarines who lost power, but still have combat capability. Control over impact time constraints of guidance law(ITCG) is derived by using sliding mode control(SMC) and Lyapunov stability theorem. The expected impact time is realized by using the notion of attack process and estimated time-to-go to design sliding mode surface(SMS). ITCG contains equivalent and discontinuous guidance laws, once state variables arrive at SMS,the equivalent guidance law keeps the state variables on SMS,then the discontinuous guidance law enforces state variables to move and reach SMS. The singularity problem of ITCG is also analyzed. Theoretical analysis and numerical simulation results are given to test the effectiveness of ITCG designed in this paper.

关键词： Lyapunov stability sliding mode control impact time salvo attack time-to-go guidance law

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鳝鱼自动剖切机设计与试验

食品与机械 2024年第2期40卷 97-103,226页

作者：刘明勇欧阳周寰韩新光向雪朱林湖北工业大学湖北省农机装备智能化工程技术研究中心湖北武汉430068

目的:设计一款专门用于剖杀细长且表面光滑的鱼类剖切机构。方法:以表体黏滑的鳝鱼为研究对象,开展夹持与剖切作业机理分析。以剖切质量和剖切时间为试验指标,探究夹轮转速、剖刀转速、夹轮表面几何形状等主要参数对剖切质量和剖切时间... 详细信息

目的:设计一款专门用于剖杀细长且表面光滑的鱼类剖切机构。方法:以表体黏滑的鳝鱼为研究对象,开展夹持与剖切作业机理分析。以剖切质量和剖切时间为试验指标,探究夹轮转速、剖刀转速、夹轮表面几何形状等主要参数对剖切质量和剖切时间的影响规律。结果:影响剖切质量的主要因素为刀片转速和夹持轮限位高度,影响剖切时间的最主要因素为夹轮转速。当夹轮限位高度为5 mm、刀片转速为1 350 r/min、夹轮转速为167 r/min时,可获得较高的剖切质量评分与剖切时间。结论:使用夹持轮可以有效输送鳝鱼,通过调配夹持轮转速、刀片转速和限位高度可以实现高效高速剖腹。

关键词：鳝鱼剖切加工剖切质量剖切时间刀片转速

基于LS-DYNA的铧式犁结构优化设计及性能分析

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农机化研究 2024年第10期46卷 153-160页

作者：刘明勇向雪闫春爱胡成龙韩新光欧阳周寰湖北工业大学武汉430068 湖北省农机装备智能化工程技术研究中心武汉430068 武昌工学院智能制造学院武汉430068

基于LS-DYNA法建立犁体与土壤的耦合接触有限元模型,讨论不同犁体导曲线、铧刃角、安装角、端点角、耕作速度对耕作过程翻垡效果和犁体应力影响,并进行试验验证。结果表明:椭圆曲面比抛物线曲面耕作时阻力更小、土壤翻垡效果更好,阻力降... 详细信息

基于LS-DYNA法建立犁体与土壤的耦合接触有限元模型,讨论不同犁体导曲线、铧刃角、安装角、端点角、耕作速度对耕作过程翻垡效果和犁体应力影响,并进行试验验证。结果表明:椭圆曲面比抛物线曲面耕作时阻力更小、土壤翻垡效果更好,阻力降低5.6%,翻垡距离提升14.8%;对犁体前进速度、铧刃角、安装角、端点角进行单因素分析,发现翻垡距离随着速度增加而增加,而随着铧刃角、安装角、端点角呈现出先增大后减小的趋势。因此,通过选取合适的速度与结构参数可以提升铧式犁的翻垡性能,减低犁体阻力。

关键词：铧式犁有限元法导曲线翻垡性能

Impact angle control over composite guidance law based on feedback linearization and finite time control

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Journal of Systems Engineering and Electronics 2018年第5期29卷 1036-1045页

作者： ZHANG Xiaojian liu mingyong LI Yang ZHANG Feihu School of Marine Science and Technology Northwestern Polytechnical University

The impact angle control over guidance(IACG) law against stationary targets is proposed by using feedback linearization control(FLC) and finite time control(FTC). First, this paper transforms the kinematics equation of guidance systems into the feedbackable linearization model, in which the guidance law is obtained without considering the impact angle via FLC. For the purpose of the line of sight(LOS) angle and its rate converging to the desired values, the second-order LOS angle is considered as a double-integral system. Then, this paper utilizes FTC to design a controller which can guarantee the states of the double-integral system converging to the desired values. Numerical simulation illustrates the performance of the IACG, in contrast to the existing guidance law.

关键词： guidance law impact angle feedback linearization finite time control global stabilization

Effects of Rosa roxburghii&edible fungus fermentation broth on immune response and gut microbiota in immunosuppressed mice

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Food Science and Human Wellness 2024年第1期13卷 154-165页

作者： Dechang Xu Jielun Hu Yadong Zhong Yanli Zhang Wenting liu Shaoping Nie mingyong Xie State Key Laboratory of Food Science and Technology China-Canada Joint Laboratory of Food Science and Technology(Nanchang)Key Laboratory of Bioactive Polysaccharides of Jiangxi ProvinceNanchang UniversityNanchang 330047China

With the rise of probiotics fermentation in food industry,fermented foods have attracted worldwide attention.In this study,protective effects of Rosa roxburghii&edible fungus fermentation broth(REFB)on immune function and gut health in Cyclophosphamide induced immunosuppressed mice were investigated.Results showed that REFB could improve the immune organ index,and promote the proliferation and differentiation of splenic T lymphocytes.In addition,it attenuated intestinal mucosal damage and improved intestinal cellular immunity.REFB administration also up-regulated the expression of IL-4,INF-γ,TNF-α,T-bet and GATA-3 mRNA in small intestine.Furthermore,administration of REFB modulated gut microbiota composition and increased the relative abundance of beneficial genus,such as Bacteroides.It also increased the production of fecal short-chain fatty acids.These indicate that REFB has the potential to improve immunity,alleviate intestinal injury and regulate gut microbiota in immunosuppressed mice.

关键词： Fermented foods Immunosuppressed mice Immune response Gut microbiota Short-chain fatty acids

Global approximation based adaptive RBF neural network control for supercavitating vehicles

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Journal of Systems Engineering and Electronics 2018年第4期29卷 797-804页

作者： LI Yang liu mingyong ZHANG Xiaojian PENG Xingguang School of Marine Science and Technology Northwestern Polytechnical University

A global approximation based adaptive radial basis function（RBF） neural network control strategy is proposed for the trajectory tracking control of supercavitating vehicles（SV）.A nominal model is built firstly with the unknown disturbance.Next, the control scheme is established consisting of a computed torque controller（CTC） for the practical vehicle and an RBF neural network controller to estimate model error between the practical vehicle and the nominal model. The network weights are adapted by employing a Lyapunov-based design. Then it is shown by the Lyapunov theory that the trajectory tracking errors asymptotically converge to a small neighborhood of zero. The control performance of the proposed controller is illustrated by simulation.

关键词： radial basis function （RBF） neural network computedtorque controller （CTC） adaptive control supercavitating vehicle（SV）

添加高铝粉煤灰对废窑具制备耐高温材料性能的影响

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耐火与石灰 2024年第1期49卷 11-16页

作者：王玲玲林凡凯刘明勇黄朝晖房明浩闵鑫中国地质大学(北京)材料科学与工程学院北京100083

为实现废窑具的高值材料化利用,以废窑具为主要原料,黏土和高铝粉煤灰为添加剂,采用干压成型法制备出坯体,分别在1100℃、1150℃、1200℃、1250℃下热处理保温3 h,制备出废窑具基耐高温材料。研究了高铝粉煤灰添加量对废窑具基耐高温材... 详细信息

为实现废窑具的高值材料化利用,以废窑具为主要原料,黏土和高铝粉煤灰为添加剂,采用干压成型法制备出坯体,分别在1100℃、1150℃、1200℃、1250℃下热处理保温3 h,制备出废窑具基耐高温材料。研究了高铝粉煤灰添加量对废窑具基耐高温材料的物相组成、显微形貌、物理性能和常温力学性能的影响,同时还研究了以不同结合剂制备的废窑具基耐高温材料的性能。结果表明:废窑具基耐高温材料的最佳工艺条件为热处理温度1250℃,高铝粉煤灰添加量为30%,所得试样的常温抗折强度为18.1 MPa,常温抗压强度为57.7 MPa;结合剂的种类对试样的常温力学性能也有一定影响。

关键词：废窑具耐高温材料高铝粉煤灰固废高值化利用

基于贝叶斯纳什均衡的不完全信息博弈目标分配决策

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西北工业大学学报 2022年第4期40卷 755-763页

作者：魏娜刘明雍西北工业大学航海学院陕西西安710072 西安石油大学电子工程学院陕西西安710065

针对AUV(autonomous underwater vehicle)协同对抗过程中的信息不完全问题,用不完全信息博弈理论研究AUV的对抗行为。以对抗双方的剩余生存概率和武器消耗量为评价指标,加入位置误差影响因子,建立了面向不完全信息的AUV博弈对抗目标分... 详细信息

针对AUV(autonomous underwater vehicle)协同对抗过程中的信息不完全问题,用不完全信息博弈理论研究AUV的对抗行为。以对抗双方的剩余生存概率和武器消耗量为评价指标,加入位置误差影响因子,建立了面向不完全信息的AUV博弈对抗目标分配模型。以贝叶斯纳什均衡理论为基础,通过虚拟参与者“自然(Nature)”,预先设置关于攻防策略类型的先验概率,选择出待分配的AUV类型,然后通过后验概率不断修正关于对方采用的目标分配策略类型的判断。提出了基于多目标离散粒子群的不完全信息目标分配求解算法,得到了博弈对抗双方的贝叶斯纳什均衡目标分配策略,为指挥官的作战指挥提供了策略选择帮助。

关键词：目标分配不完全信息博弈贝叶斯纳什均衡离散粒子群算法