一种新的灰色多属性决策方法

针对模糊群体多属性决策问题,提出一种新的灰色多属性决策方法.该方法依据一般的灰色关联分析方法的基本思路,将灰色关联度和欧氏距离有机结合,构造出一种平均相似度对方案进行评价.平均相似度同时反映了方案与正负理想方案之间的位置和数据曲线的相似性差异,其物理意义更加明确.最后通过算例表明了所提出方法的可行性和有效性.     

Near surface flaw detection by ultrasonic critical angle imaging

Acoustic critical angle measurements usually involve broad beam or global isonification of a water-solid interface. In order to obtain local interface data, it is convenient to use a focused acoustic source with lens axis at incident angle and point-receiver at specular reflection angle . By scanning this combination at various critical angles (=_crit), interface waves are generated locally near the lens focus. These waves penetrate the solid to a depth of approximately one shear wavelength _T and are modulated by discontinuities such as flaws, inclusions, and debonds that may be present there. A radiated longitudinal wave in water accompanies these modulated interface waves and carries information on subsurface flaws to the point-detector along the direction of a specularly reflected wave. By scanning the focus-receiver combination along the interface, the receiver output may be used to form images of local subsurface detail. We show that in anisotropic materials, such as crystals, there are generally two different _crit where a radiating interface wave provides subsurface information. We also discuss special problems associated with the use of a focused acoustic source including nonlinear effects (generation of harmonics) in the water.     

金属基仿生减阻材料元素与性能量化分析

借助灰色关联度分析方法,建立了触土部件金属基仿生减阻材料构成元素与性能之间的灰色关系分析模型,通过仿生犁壁材料的试验数据计算了仿生犁壁材料构成元素C、Re、Mn等分别与仿生性能指标接触角、硬度、成本等之间的关联度。分析了仿生犁壁材料元素构成比例与各性能指标之间的量化关系,为地面仿生机械减阻材料的研究提供了又一种科学分析方法。     

平面二维挟沙力公式系数的确定

水流挟沙能力反映了运动水体所能挟带泥沙的最大能力,确定水流挟沙力公式对于泥沙数学模型的发展具有重要意义,而关键是其系数的最佳确定.通常挟沙力公式在实际应用时都要用实测资料对系数进行率定,对李义天的平面二维挟沙力公式,利用最小二乘法与灰色关联度相结合对其系数进行确定.     

灰色软测量在介质填充率检测中的应用研究

通过对磨矿过程原理的分析，提出了基于径向基（RBF）网络的软测量方法，对以往无法在线检测的球磨机关键参数——介质填充率进行实时估计．针对现有软测量辅助变量选择方法存在的问题，结合灰关联分析理论，提出了一致关联度算法，并应用该算法实现了介质填充率软测量建模中辅助变量的选择．仿真结果表明，该软测量方法估计的平均相对误差保持在0．7％以下，可满足实际需要．同时，一致关联度算法可以准确的提取变量间的相关性，是一种有效的辅助变量选择方法．     

一种同构、非同构布局模式构造算法

给出了一种基于完全关联图的准确构造同构、非同构布局模式的算法,并给出了其计算复杂度及适应范围.与李广强等（2003）的布局模式构造方法相比较表明,本算法能构造准确布局模式,适用范围较广,计算复杂度低,前者为O（n^3）,本文为O（n）,O（n^2）或O（n^3）.     

基于矢量观测确定卫星轨道姿态:欧拉角估计器

针对“矢量观测+陀螺”这种典型的三轴稳定卫星姿态确定系统配置模式,采用欧拉角作为姿态参数,应用扩展卡尔曼滤波技术综合处理姿态测量信息,给出了具有良好滤波性能的轨道姿态估计算法.在算法的设计过程中,针对单矢量观测情况,通过改进协方差修正算法加快了状态估值的收敛速度;针对多矢量观测情况,把 QUEST 法作为矢量观测数据压缩技术有效地结合进姿态估计器中,使得在多矢量观测情况下的滤波修正算法得到了简化.     

带双腹板、顶底角钢梁柱连接有限元分析

对带双腹板顶底角钢梁柱半刚性连接进行了有限元分析，得到了此类连接在单向荷载作用下的应力发展状况、应力分布以及破坏形式，同时还对有限元分析结果与理论分析、试验结果做出了对比，得到了一些结论。     

Transition from split streamlines to dip-coating during Langmuir–Blodgett film deposition

Mono-molecular films of arachidic acid were deposited on glass slides using the Langmuir–Blodgett (LB) technique. The liquid subphases were dilute solutions of ZnSO₄ at different pH. Glass slides were treated to create contact angles (θ) ranging from approximately 15° for clean glass slides, to contact angles greater than 120° for slides treated with ferric stearate. Intermediate contact angles were created by immersing slides in solutions of Sigmacote^® of varying concentration. Very small contact angles, θ≈0° were obtained with clean glass slides at high pH values. LB deposition data and transfer ratios (TR) were recorded for up-stroke and down-stroke operation. During upstroke, TR increase with decreasing contact angles reaching a maximum TR close to 100% when the receding contact angle is approximately 15–20°. This is typical of the split-ejection flow pattern found during up-stroke. For very small contact angles, i.e. less than 10°, TR suddenly become zero indicating a transition to a dip-coating flow pattern. During down-stroke operation, TR is zero or negative for small contact angles, reaching a maximum TR approximately 100% for contact angles larger than 120°.     

A Method of Determining the Axes of a Three-Component Magnetometer Sensor with Respect to the Axes of the Navigation System of a Ferromagnetic Mobile Object

A method of determining the orientation of the axes of a three-component magnetometer sensor with respect to the axes of the navigation system of a ferromagnetic mobile object is considered, which eliminates the effect of the magnetization of the object on the determination of the angular position of the axes of the sensor with respect to the axes of the navigation system.