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复杂载荷下舰炮后坐试验台架结构优化

火炮发射与控制学报 2024年第4期45卷 26-34页

作者：谭敏马保吉刘彬西安工业大学兵器科学与技术学院陕西西安710021 铜川职业技术学院机电工程学院陕西铜川727031

后坐试验台架是舰炮后坐试验系统的支撑结构,其刚强度会直接影响测试准确性和试验安全性。为了进一步提高台架的刚强度,开展了正常工作与摇摆载荷复合作用下的结构优化研究。通过动力学分析模型的建立,获得后坐与复进运动过程的载荷变... 详细信息

后坐试验台架是舰炮后坐试验系统的支撑结构,其刚强度会直接影响测试准确性和试验安全性。为了进一步提高台架的刚强度,开展了正常工作与摇摆载荷复合作用下的结构优化研究。通过动力学分析模型的建立,获得后坐与复进运动过程的载荷变化规律,采用有限元分析得到受最大载荷时的应力与变形,对试验台架的厚度参数进行了灵敏度分析和试验设计,根据Kriging模型建立了关键板梁厚度同最大应力和变形的响应曲面,结合多目标优化法预测最优参数方案并验证了优化效果。结果表明:台架上横梁2与复进机前承座底部易发生损坏;调整上横梁2、上斜肋板及上纵板的厚度可有效提高台架刚强度。

关键词：动力学仿真横摇纵摇有限元分析灵敏度响应面优化

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基于CFD法的桨前预旋导流罩设计与分析

上海海事大学学报 2024年第1期45卷 85-91页

作者：蔺永杰张宝吉上海海事大学海洋科学与工程学院上海201306

为满足现有船舶能效指数(energy efficiency existing ship index,EEXI)要求,达到节能减排的目的,基于水动力学基础理论,设计一种桨前预旋导流罩节能装置。该装置由加速型导管和导叶组成:加速型导管可以使水流紧贴船体,改善流动分离,使... 详细信息

为满足现有船舶能效指数(energy efficiency existing ship index,EEXI)要求,达到节能减排的目的,基于水动力学基础理论,设计一种桨前预旋导流罩节能装置。该装置由加速型导管和导叶组成:加速型导管可以使水流紧贴船体,改善流动分离,使进入螺旋桨的水流更加均匀,从而提高螺旋桨的推进效率;导叶可以为螺旋桨提供预旋,减少能量损失。利用计算流体动力学(computational fluid dynamics,CFD)软件对比分析优化前后的船尾流场和伴流分布。通过组合与优化节能装置的设计参数,节能装置的节能效果可达7.96%。与自航试验结果比较,证明了采用CFD软件进行桨前预旋导流罩节能装置设计是切实可行的。

关键词：桨前预旋导流罩计算流体动力学(CFD) 节能装置数值模拟

基于误差预测的矿山贯通测量质量控制优化方法研究

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江西煤炭科技 2024年第3期 182-184,187页

作者：马保稷晋能控股煤业集团浙能麻家梁煤业公司山西朔州036000

针对矿井贯通测量误差影响较大的问题,为使加测陀螺定向边数量和位置都达到最优效果,分析了陀螺仪的工作原理,研究了贯通测量误差预测方法,按照麻家梁煤业(二号井)13采区和14采区测量需求和相关规定提出两套优化方案:方案一加测8条间距... 详细信息

针对矿井贯通测量误差影响较大的问题,为使加测陀螺定向边数量和位置都达到最优效果,分析了陀螺仪的工作原理,研究了贯通测量误差预测方法,按照麻家梁煤业(二号井)13采区和14采区测量需求和相关规定提出两套优化方案:方案一加测8条间距分布均匀的陀螺定向边,13采区和14采区在支导线终边进行加测;方案二对13采区和14采区加测位置和大巷中原陀螺定向边位置不发生改变,调整其他陀螺定向边位置。通过实测,两套优化方案均能满足矿井贯通测量需求和相关设计要求,其中方案二能实现陀螺定向边最大限度优化,误差分布更均匀,中误差减小到12.5 mm。

关键词：贯通测量陀螺定向误差预测优化方案

Study on Application of Pour Point Depressant for Diesel Fuel

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China Petroleum Processing & Petrochemical Technology 2008年第2期10卷 19-22页

作者： Zhang baoji SINOPEC Research Institute of Petroleum Processing Beijing 100083

Taking into account the actual crude slate processed at the refinery, it is necessary to make reasonable combination and blending of crude oils. In order to cope with high wax content in diesel fuel it is proposed to appropriately regulate the refining process scheme and add additives to refined products. This measure after being applied in the production practice has brought about good results and has met the needs of commercial production.

关键词： pour point depressant for diesel fuel high-wax diesel blending commercial application

Multiobjective Optimization of Hull Form Based on Global Optimization Algorithm

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Journal of Shanghai Jiaotong university(Science) 2022年第3期27卷 346-355页

作者： LIU Jie ZHANG baoji Merchant Marine College Shanghai Maritime UniversityShanghai 201306China College of Ocean Science and Engineering Shanghai Maritime UniversityShanghai 201306China

Rankine source method,optimization technology,parametric modeling technology,and improved multiobjective optimization algorithm were combined to investigate the multiobjective optimization design of hull form.A multiobjective and multilevel optimization design framework was constructed for the comprehensive navigation performance of *** software was utilized as the optimization platform,and nondominated sorting genetic algorithm II(NSGA-II)was used to conduct multiobjective optimization research on the resistance and sea-keeping performance of the ITTC Ship A-2 fishing *** objectives of this study are heave/pitch response amplitude and wave-making *** the displacement and the length between perpendiculars as constraints,we optimized the profile of the *** hierarchy process(AHP)and technique for order preference by similarity to ideal solution(TOPSIS)were used to sort and select Pareto solutions and determine weight coefficient of each navigation performance objective in the general ***,the hydrodynamic performance before and after the parametric deformation of the hull was *** results show that both the wave-making resistance and heave/pitch amplitude of the optimized hull form are reduced,and the satisfactory optimal hull form is *** results of this study have a certain reference value for the initial stage of multiobjective optimization design of hull form.

关键词： multiobjective optimization Rankine source method global optimization algorithm nondominated sorting genetic algorithm II(NSGA-II)

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水下作业装置直航状态水动力学研究

船舶工程 2024年第7期46卷 149-155,165页

作者：张港庆董建帅苏世杰殷宝吉晏飞江苏科技大学机械工程学院江苏镇江212003 中国船舶科学研究中心江苏无锡214082 深海技术科学太湖实验室江苏无锡214082

为了研究不同雷诺数对水下作业装置水动力特性的影响,采用RANS控制方程和RNG k-ε湍流模型对水下作业装置进行数值模拟。首先对SUBOFF潜艇进行了数值模拟,并与试验值进行比较,验证数值模拟的有效性和可靠性。研究在直航的状态下不同雷... 详细信息

为了研究不同雷诺数对水下作业装置水动力特性的影响,采用RANS控制方程和RNG k-ε湍流模型对水下作业装置进行数值模拟。首先对SUBOFF潜艇进行了数值模拟,并与试验值进行比较,验证数值模拟的有效性和可靠性。研究在直航的状态下不同雷诺数对表面压力、涡量以及湍流动能的影响。数值模拟的结果表明,随着雷诺数增加,水下作业装置在迎流处表面压力增大,机械臂后涡量和湍流动能增大。研究结果可为水下作业装置的稳定性优化提供参考。

关键词：水下作业装置水动力雷诺数计算流体动力学

Effects of non-Gaussian noise on the dynamical properties of a logistic system

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Chinese Physics B 2013年第6期22卷 228-232页

作者：王参军 Nonlinear Research Institute Baoji University of Arts and Sciences

The dynamical properties of a tumor cell growth system described by the logistic system with coupling between non- Gaussian and Gaussian noise terms are investigated. The effects of the nonextensive index q on the stationary properties and the transient properties are discussed, respectively. The results show that the nonextensive index q can induce the tumor cell numbers to decrease greatly in the case of q 〉 1. Moreover, the switch from the steady stable state to the extinct state is speeded up as the increases of q, and the tumor cell numbers can be more obviously restrained for a large value of q. The numerical results are found to be in basic agreement with the theoretical predictions.

关键词： logistic growth system non-Gaussian noise dynamical properties

UNRAVELING ECOTOURISM PRACTICE:PROBLEM ANALYSIS BASED ON STAKEHOLDERS

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Chinese Geographical Science 2004年第1期14卷 82-89页

作者： L1UXue-mei baoji-gang CenterforTourismPlanningandResearch ZhongshanUniversityGuangzhou510275P.R.China

Despite the considerable literatures defined what Ecotourism is or should be, it is experiencing vario- us practices with different features. Now the term "Ecotourism" is almost applied to all tourism activities which are based on nature. Faced to the flooding of those unqualified Ecotourism, it is of great necessity to put forward professional claim. The present writer holds that the key to the realization of rigorous Ecotourism chiefly lies in the relationships among the different interest groups involved in it. So the focus of this paper is just on giving a special analysis to the interest relations between those stakeholders which include local government, tour-operators, local residents and eco-tourists, and thus helping to find out what wrong is in those unqualified Ecotourism and the roots of those problems.

关键词： Ecotourism stakeholder interest relations

Faulty Feeder Identification and Fault Area Localization in Resonant Grounding System Based on Wavelet Packet and Bayesian Classifier

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Journal of Modern Power Systems and Clean Energy 2020年第4期8卷 760-767页

作者： Jingwen Chen Enliang Chu Yingchun Li baoji Yun Hongshe Dang Yali Yang Power System Relay Protection Laboratory of Shaanxi University of Science and Technology Xi’anChina Xi’an Xirui Control Technology Co. Ltd.Xi’anChina State Grid Shaanxi Electric Power Company Maintenance Company Xi’anChina

Accurate fault area localization is a challenging problem in resonant grounding systems(RGSs).Accordingly,this paper proposes a novel two-stage localization method for single-phase earth faults in ***,a faulty feeder identification algorithm based on a Bayesian classifier is *** characteristic parameters of the RGS(the energy ratio,impedance factor,and energy spectrum entropy)are calculated based on the zero-sequence current(ZSC)of each feeder using wavelet packet ***,the values of three parameters are sent to a pre-trained Bayesian classifier to recognize the exact fault *** this result,the faulty feeder can be finally *** find the exact fault area on the faulty feeder,a localization method based on the similarity comparison of dominant frequency-band waveforms is proposed in an RGS equipped with feeder terminal units(FTUs).The FTUs can provide the information on the ZSC at their *** wavelet-packet transformation,ZSC dominant frequency-band waveforms can be obtained at all FTU *** of the waveforms of characteristics at all FTU points are calculated and *** neighboring FTU points with the maximum diversity are the faulty sections finally *** proposed method exhibits higher accuracy in both faulty feeder identification and fault area localization compared to the previous ***,the effectiveness of the proposed method is validated by comparing simulation and experimental results.

关键词： Resonant grounding system single-phase earth fault faulty feeder identification fault area localization wavelet packet Bayesian classifier