目标回声分类特征的冗余性评价

对目标回声分类特征的冗余性进行评价与分析.对于2个特征维之间的冗余性,采用基于特征间线性相关系数作为冗余性度量,通过特征的相关系数矩阵分析了特征维之间的冗余度.此外,本文提出了基于特征协方差矩阵近零特征值的冗余性度量,据此可以进一步分析特征组内部的多维组合冗余.最后,利用以上2种冗余性度量,对5种目标回声分类特征各自的...     

一类基于模型预测的船舶自动舵控制策略研究

针对自动舵K-T模型的特点改进了传统的动态矩阵控制方法.改进后的方法避免了K-T模型截断误差的影响,能有效校正模型参数变动的影响,使之可用于船舶自动舵的控制.仿真结果证明了此改进方法的可行性.     

基于改进层次分析法的舰炮武器系统作战效能评估

舰炮武器系统作战效能评估是一个多目标评价过程,利用层次分析法可以对此非定量事件作定量分析,而一致性检验在层次分析法中是必不可少的。在实际评估中,一般都凭着大致的估计来调整判断矩阵使之满足一致性要求,这样具有很大的盲目性。利用最优传递矩阵的概念,对层次分析法进行改进,使之自然满足一致性要求,直接求出权重值。效能评价实例说明了基于最优传递矩阵的层次分析法的可行性和有效性。     

影响矩阵法在施桥大桥吊杆二次调索中的应用

在系杆拱桥施工过程中,为增大结构的安全储备并保证主梁受力安全,通常对吊杆采用两次张拉,最终达到设计成桥索力,由此提出二次调索施调索力、顺序的计算问题.以影响矩阵理论为基础,建立了二次调索最优控制的数学模型,采用惩罚函数法求解,该方法计算精确、简便、实用,也可用于成桥后索力的误差调整.     

Motorcycle suspension design using matrix inequalities and passivity constraints

This paper presents a design methodology for the suspension system of a novel aerodynamically efficient motorcycle. Since the machine’s layout and the rider’s seating position are unconventional, several aspects of the machine design, including the suspension, must be reviewed afresh. The design process is based on matrix inequalities that are used to optimise a road-grip objective function – others could be used equally well. The design problem is cast as the minimisation of an H ₂ cost with passivity constraints imposed on the suspension transference. The resulting bilinear matrix inequality problem is solved using a locally optimal iterative algorithm. The matrix inequality-type characterisation of positive real functions permits the optimisation of the suspension system over an entire class of passive admittances. Torsional springs, dampers and inerters are then used to construct networks corresponding to the optimal (positive real) admittances. Networks of first, second, third and fourth orders are considered, and an argument based on the compromise between complexity and improved grip is made for the most suitable suspension configuration. Finally, the effects of improved road grip on the stability of the vehicle’s lateral dynamics are analysed.     

交通网络中动态OD矩阵估计模型研究

动态起点-迄点（OD）矩阵为智能交通系统提供所需的基础数据。为了提高交通网络中动态OD矩阵估计的精度,在最小化路段实际交通量和分配交通量之间差值以及最小化历史OD矩阵和待估计OD矩阵之间差值的基础上,将浮动车采集信息融合到OD矩阵估计过程中;在动态网络加载过程中,OD矩阵估计值如果大于加载车辆数会使网络中的定点问题求解发散。为了避免该情况的发生,基于广义最小二乘模型并引入容量约束,提出1种带不等式约束的动态OD矩阵估计方法。仿真实验表明,该方法对于OD矩阵估计的精度较好,优于带滑动窗的广义最小二乘算法。     

一种基于灵敏度矩阵进行桥梁损伤识别的方法

重点研究了一种基于灵敏度矩阵对桥梁进行损伤识别的方法。基于振动分析的矩阵摄动理论,首先讨论了求取模态参数对结构物理参数灵敏度矩阵的方法,形成灵敏度矩阵的过程中避免了偏微分计算;基于灵敏度矩阵,建立了桥梁的损伤识别模型,并给出了此模型具体的求解方法;然后利用Guyan缩减的方法来缩减结构的模态自由度,保证了在进行损伤识别的过程中利用较少的模态参数,进而提高了方法的实用性;最后把所述方法应用于三跨预应力混凝土连续箱梁桥的实际损伤诊断工程。结果表明,利用所述方法进行预应力混凝土连续梁桥的损伤识别是有效的。     

Pole location control design of an active suspension system with uncertain parameters

This paper addresses the problem of robust control design for an active suspension quarter-car model by means of state feedback gains. Specifically, the design of controllers that assure robust pole location of the closed-loop system inside a circular region on the left-hand side of complex plane is investigated. Three sufficient conditions for the existence of a robust stabilizing state feedback gain are presented as linear matrix inequalities: (i) the quadratic stability based gain; (ii) a recently published condition that uses an augmented space and has been here modified to cope with the pole location specification; (iii) a condition that uses an extended number of equations and yields a parameter-dependent state feedback gain. Unlike other parameter-dependent strategies, neither extensive gridding nor approximations are needed. In the suspension model, the sprung mass, the damper coefficient and the spring constant are considered as uncertain parameters belonging to a known interval (polytope type uncertainty). It is shown that the parameter-dependent gain proposed allows one to impose the closed-loop system pole locations that in some situations cannot be obtained with constant feedback gains.     

路网容量及最大流算法研究

对城市道路网的现有路网容量理论和模型进行了研究,在国内外现有较成熟的路网研究方法的基础上,分析了各种模型的假设条件、模型特点以及模型应用范围,并基于最大流、最小割理论分析了国内外现有的最大流算法及其缺陷,提出了改进的算法和在Matlab中的实现方式。     

高速公路出入口OD矩阵推算方法

研究已建高速公路历年断面流量变化规律,对制定各项管理措施和项目评估都至关重要。在我国断面交通流量硬件观测设施不十分普及的情况下,各收费站口数据的整理统计分析显得尤为重要。本文结合高速公路实际,提出以收费站数据为基础,进行高速公路出入口OD流量推算的一般方法,并对太旧高速公路2002年某天数据进行实例分析。