基于舰载无人机的海战场打击效果评估研究

针对基于图像理解的海战场打击效果评估,研究基于图像理解的海战场打击效果评估模型,讨论图像处理、毁伤数据库模型和毁伤等级算法模型问题,给出打击效果评估的数学模型和评估流程,对尚处于理论研究阶段的海上目标打击效果评估问题有积极的参考意义.     

炮兵目标遥感图像毁伤判据的建立与分析

目标毁伤判据是炮兵进行精确毁伤效果评估基础,对评估结果的优劣有重要影响。在分析目标结构、易损性和目标图像特征的基础上,提出了以目标的遥感图像特征为底层毁伤因素的遥感图像毁伤判据建立方法,并建立了毁伤判据。最后,对遥感图像毁伤判据进行了实验验证。实验结果表明,与传统的毁伤判据相比,基于遥感图像的毁伤判据评估结果更加精确,实现了自动毁伤效果评估。     

不规则形状目标毁伤效果计算方法

针对不规则形状目标的毁伤效果评估问题,研究了一种基于不规则形状目标灰度图像进行毁伤效果评估的新方法。通过采用不同灰度等级表示目标不同部位的重要性,结合像素点分析法进行蒙特卡罗模拟评估射击毁伤效果,分析了基于灰度图像运用像素点法评估不规则形状目标毁伤效果的基本步骤,并在Matlab软件中通过实例分析进行了仿真验证。仿真结论验证了该方法的可行性和便捷性。     

目标毁伤指标量化问题分析

通过分析国内外毁伤指标分类,提出了目标毁伤指标的五种类型.结合战场实际,建立目标重要性量化模型.在确定目标重要性基础上,通过概率分布的形式来确定目标的毁伤指标.     

基于毁伤树构建系统目标毁伤评估模型研究

针对系统目标毁伤评估的特点和要求,在分析目标功能结构的基础上,提出了基于毁伤树构建毁伤评估模型的方法。提出的基于目标功能的毁伤评估算法的最大优点在于简化了系统目标毁伤评估的复杂性,将作战效能的获取和毁伤意图有机结合在一起,克服了传统毁伤评估的局限性,为复杂系统目标的毁伤评估与建模提供了新的方法。     

目标毁伤指标量化问题分析

通过分析国内外毁伤指标分类,提出了目标毁伤指标的五种类型。结合战场实际,建立目标重要性量化模型。在确定目标重要性基础上,通过概率分布的形式来确定目标的毁伤指标。     

海军编队作战岸上目标毁伤效果评估研究

近期几场高技术条件下局部战争中目标毁伤评估方面具有许多经验和教训,海战中对岸上目标毁伤效果评估应得到高度重视.针对我海军目前作战能力和作战方式,开展对岸火力毁伤效果评估研究,为合理运用海军火力资源、提高海军火力运用效能提供科学依据.     

基于遥感图像的舰船毁伤效果评估方法研究

提出了一种基于遥感图像变化检测的舰船毁伤效果评估方法,主要包括图像预处理、舰船检测、毁伤前后目标区域提取、特征提取和分级评估五个部分。研究了目标区域提取和变化特征选取等问题,提取几何特征与纹理特征进行分级评估。基于视景仿真技术进行了舰船毁伤效果模拟,采用模拟的图像进行毁伤效果评估仿真实验。实验结果表明,该方法能有效地实现对海上舰船目标的毁伤效果评估。     

打击核电厂目标的毁伤指标分析

对打击核电厂进行功能毁伤评估和核辐射安全评估是评估核电厂目标毁伤效果的首要任务。采用目标特性分析方法构建核电厂功能毁伤程度指标体系与核电厂辐射程度指标体系,并对指标体系中具体指标进行了定量分析,为打击核电厂目标的毁伤评估建模打下了铺垫。     

舰船目标毁伤特征采集效果评估软件设计

快速准确评估舰船目标毁伤特征能够确保取得好的海上作战效果,同时也可以为技术人员提供好的决策支持。传统的舰船目标毁伤特征采集效果评估软件缺少与初始状态的对比,只能单一的记录毁伤后的状态,对比性不够强烈。为了解决此问题,基于贝叶斯网络推理技术研究了一种新的采集效果评估软件,设计了毁伤树评估流程,利用可视化界面记录船舶的初始状态、遭受毁伤后的状态,以及二维模拟后的毁伤状态。为了检测该软件的实际工作效果,与传统软件系统进行对比,设计了对比实验。实验结果表明,该软件能够综合性地评价目标船舶的毁伤情况,为海上攻击作战提供有利的技术支持。     

一种空中目标空间分群算法

针对信息化战场条件下具有集群作战的特点,提出了一种空中目标空间群识别算法。依据目标的类型、属性、位置和速度等特征,综合考虑目标间的相似度,可以有效地对不同类型空中目标进行空间群划分,在此基础上,获得目标群参数,为进一步的战场态势评估奠定基础。     

液化石油气船疲劳强度校核方法

提出了改进的ＦＡＳＳ（Ｆａｔｉｇｕｅ Ａｓｓｅｓｓｍｅｎｔ ｏｆ Ｓｈｉｐ Ｓｔｒｕｃｔｕｒｅｓ）评估系统,使之适用于液化石油ＬＰＧ,Ｌｉｑｕｉｆｉｅｄ Ｐｅｔｒｏｌｅｕｍ Ｇａｓ）船船体结构的疲劳寿命校核。该系统从疲劳分析的基本原理出发,以疲劳累积损伤度公式为理论基础,可对船体结构进行疲劳寿命校核。通过对１６５００ｍ＾３ＬＰＧ船的验算,表明改进后的方法能有效评估ＬＰＧ船舶体结构的疲劳寿命。     

基于工程简化的Topside管廊结构疲劳寿命分析

对“船形”海洋工程结构的疲劳评估方法进行了详细讨论,并结合有限元法,采用工程简化实用的疲劳评估方法,对某海洋工程Topside管廊结构的疲劳损伤和疲劳寿命进行计算分析,验证了该结构抗疲劳设计的合理性。此疲劳分析过程简单方便,可为类似工程结构的疲劳寿命分析提供参考。     

液货晃荡对油船结构性能的影响研究

论文研究了液货晃荡对油船的结构响应影响研究.论文对比研究了考虑液货晃荡与忽略液货晃荡影响的油船结构强度,包括设计波参数对比,最大扭矩、最大垂向弯矩、最大水平弯矩控制参数对应工况下的结构应力分布特征对比.对比研究了考虑液货晃荡与忽略液货晃荡影响的油船疲劳强度,包括满载状态下的疲劳评估结果、疲劳损伤的浪向角分布结果对比.论文针对液货晃荡对油船结构响应影响提出的研究结论,对油船的结构设计及评估具有重要的研究意义.     

圆筒型FPSO上部模块支撑结构疲劳分析

与船型FPSO相比,圆筒型FPSO没有明显的总纵弯曲,上部模块与船体结构之间通常采用刚性支墩来连接,水平运动所产生的弯矩和装/卸载引起的船体垂向变形对模块支撑结构的影响较为显著。因此,以“希望6号”圆筒型FPSO上部模块支撑结构为研究对象,基于DNVGL船级社规范,介绍一种简化疲劳分析方法。以FPSO运动加速度和船体变形载荷作为载荷输入条件,利用SESAM/GeniE软件进行有限元分析,得到结构在所有组合工况下应力的扫描计算结果。根据作业海域各个方向波浪发生的概率,运用简化疲劳分析方法计算得到所关注节点的疲劳损伤和各个工况对结构节点疲劳损伤度的贡献。结果表明,所关注节点的疲劳强度均满足设计疲劳强度要求;同一节点的疲劳损伤对不同浪向的敏感度不一样。该简化疲劳分析方法同样适用于承受周期性载荷的FPSO上部模块主结构和其他型式海洋结构物的疲劳分析。     

Environmental lumping for efficient fatigue assessment of large-diameter monopile wind turbines

Fatigue damage is one of the governing factors for the design of offshore wind turbines. However, the full fatigue assessment is a time-consuming task. During the design process, the site-specific environmental parameters are usually condensed by a lumping process to reduce the computational effort. Preservation of fatigue damage during lumping requires an accurate consideration of the met-ocean climate and the dynamic response of the structure. Two lumping methods (time-domain and frequency-domain) have been evaluated for a monopile-based 10 MW offshore wind turbine, both based on damage-equivalent contour lines. Fatigue damage from lumped load cases was compared to full long-term fatigue assessment. The lumping methods had an accuracy of 94–98% for the total long-term fatigue damage and 90% for individual wind speed classes, for aligned wind and waves. Fatigue damage was preserved with the same accuracy levels for the whole support structure. A significant reduction of computational time (93%) was achieved compared to a full long-term fatigue assessment. For the cases with 30° and 60° wind-wave misalignment, there was a mean underestimation of approximately 10%. Variations in penetration depth did not affect the selection of the lumped sea-state parameters. This work presents a straightforward method for the selection of damage-equivalent lumped load cases, which can adequately preserve long-term fatigue damage throughout the support structure, providing considerable reduction of computational effort.     

海底掩埋目标的散射特性分析

在对不同掠射角条件下掩埋目标的散射特性进行分析的基础上,认为低频、宽带、窄波束在小掠射角的情况下是适合掩埋目标探测和识别的,并对掩埋目标探测和识别声纳设计提出了建议。     

Damage assessment of a tunnel-type structure to protect submarine power cables during anchor collisions

The dynamic characteristics of a tunnel structure used to protect underwater power cables, the so-called A-duct, were determined for anchor collisions to provide a procedure for damage assessment and recommendations. The required physical quantities of five target anchors, including the drag coefficient, were obtained using an element-based finite-volume method and ANSYS-CFX software. The terminal velocities of the anchors were then calculated to maximize the colliding kinetic energy. For collision analysis, four parameters (anchor type, ground condition, collision velocity, and collision point) were considered, and the A-duct was modeled based on the Riedel–Hiermaier–Thoma concrete model using ANSYS-Autodyn software. Our analysis results indicated severe damage (D = 1) for most of the gauge points; the damaged area and level increased with the anchor weight. The results showed that the damage was concentrated in the collision area for stock anchors; however, for stockless anchors, damage was also evident in adjacent areas (i.e., damage propagation) due to the anchor head shape as well as the transfer mechanism provided by its reinforcing nets. Accordingly, the 2-ton stock anchor caused more damage at the gauge points near the collision location than the 2-ton stockless anchor. Second, regardless of the ground conditions and rotation angle of the anchor heads with respect to the vertical axis, the damage levels were almost identical. Fixed boundary conditions and non-rotational angle were sufficient for the model used. Third, the damaged areas became smaller when the anchor collision locations deviated from the reference gauge point (P1), i.e., the center of the A-duct. Finally, a comparison of the field-test results to equivalent numerical collision simulations indicated that the size of the predicted and experimentally observed damaged areas were in agreement within 7%.