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1.
Image matching technology is theoretically significant and practically promising in the field of autonomous navigation.Addressing shortcomings of existing image matching navigation technologies,the concept of high-dimensional combined feature is presented based on sequence image matching navigation.To balance between the distribution of high-dimensional combined features and the shortcomings of the only use of geometric relations,we propose a method based on Delaunay triangulation to improve the feature,and add the regional characteristics of the features together with their geometric characteristics.Finally,k-nearest neighbor(KNN)algorithm is adopted to optimize searching process.Simulation results show that the matching can be realized at the rotation angle of-8°to 8°and the scale factor of 0.9 to 1.1,and when the image size is 160 pixel×160 pixel,the matching time is less than 0.5 s.Therefore,the proposed algorithm can substantially reduce computational complexity,improve the matching speed,and exhibit robustness to the rotation and scale changes.  相似文献   

2.
To improve the efficiency of gate reassignment and optimize the plan of gate reassignment,the concept of disruption management is introduced,and a multi-objective programming model for airport gate reassignment is proposed.Considering the interests of passengers and the airport,the model minimizes the total flight delay,the total passengers′walking distance and the number of flights reassigned to other gates different from the planned ones.According to the characteristics of the gate reassignment,the model is simplified.As the multi-objective programming model is hard to reach the optimal solutions simultaneously,a threshold of satisfactory solutions of the model is set.Then a simulated annealing algorithm is designed for the model.Case studies show that the model decreases the total flight delay to the satisfactory solutions,and minimizes the total passengers′walking distance.The least change of planned assignment is also reached.The results achieve the goals of disruption management.Therefore,the model is verified to be effective.  相似文献   

3.
Aiming at the large cost of calculating variable bandwidth kernel particle filter and the high complexity of its algorithm, a self-adiusting kernel function particle filter is presented. Kernel density estimation is facilitated to iterate and obtain new particle set. And the standard deviation of particle is introduced in the kernel bandwidth. According to the characteristics of particle distribution, the bandwidth is dynamically adjusted, and the particle distribution can thus be more close to the posterior probability density model of the system. Meanwhile, the kernel density is used to estimate the weight of updating particle and the system state. The simulation results show the feasibility and effectiveness of the proposed algorithm.  相似文献   

4.
变化和重构是快速可重构信息系统 (RRIS)的两个核心概念 ,RRIS对变化的适应或演化能力使它优于传统信息系统。本文首先提出 RRIS的体系结构 ,然后以 RRIS框架为重点 ,讨论框架的定义、分类及设计 ,研究框架的构成、构成元素 (业务构件 )的设计及构件如何在构架的组织下协调地安插在 CORBA的软总线上 ,实现类似硬件IC的即插即用。构件在框架上即插即用的灵活机制及热点构件 (反映变化 )的灵活运用 ,提高了框架的可扩展性、可定制性 ,从而提高了 RRIS适应变化的可重构性。  相似文献   

5.
The Certificate of Registration is a legal document required by international convention(ICAO),and requires the aircraft’s registration to be marked on the exterior of every civil aircraft.The registration is an alphanumeric code to identify a single aircraft.which al indicates the country of registration of the aircraft,and must be displayed when the aircraft is in operation.  相似文献   

6.
There are two types of singularities in the linear thermoelasticity.The first one arises in the field of stresses if a force is applied to one point of the body.This singularity is physical and should be accepted.The second type of singularities is nonphysical and they arise in the fields of displacements and temperatures.There exist the nonlocal theories and gradient theories which have the goal to introduce the finite stresses instead of the infinite ones.The MAC model of the thermoelasticity is created to avoid the nonphysical singularities and it accepts the infinite stresses.MAC is the method of additional conditions,which allows introducing the new model to use the classical model,plus additional condition of the physical nonsingularity and/or condition of the good behavior of the solutions at infinity.The MAC Green′s functions for the heat conduction and for the elasticity could be introduced using the differential MAC models.The infinite and finite bodies are considered.The principle of superposition is applied to obtain the integral equations to solve the boundary value problems.The strength criteria based on finite stresses could be changed in this model because the infinite stresses are allowed.The strength criteria based on deformations are applicable.Classification of MAC models is given.  相似文献   

7.
A new approach to modifying the stiffness and mass matrices of finite element models is presented to improve the calculation precision. By measuring the mode frequencies and shapes of both of the original and the new structures with changed stiffness and mass, the stiffness and mass matrices of the finite element model can be updated through matrices calculation and solving algebra equations. Taking a multi-freedom model as an example, the relation between the number of the modes and the correction precision of stiffness and mass matrix elements is researched. The facility and precision of the method are totally confirmed especially when the modeling error is known limited to a definite local range. The feasibility of the approach is proven by an effective engineering application to the model updating of a wing piece used in flutter test.  相似文献   

8.
The dynamical and physical behavior of a complex system can be more accurately described by using the fractional model.With the successful use of fractional calculus in many areas of science and engineering,it is necessary to extend the classical theories and methods of analytical mechanics to the fractional dynamic system.Birkhoffian mechanics is a natural generalization of Hamiltonian mechanics,and its core is the Pfaff-Birkhoff principle and Birkhoff′s equations.The study on the Birkhoffian mechanics is an important developmental direction of modern analytical mechanics.Here,the fractional Pfaff-Birkhoff variational problem is presented and studied.The definitions of fractional derivatives,the formulae for integration by parts and some other preliminaries are firstly given.Secondly,the fractional Pfaff-Birkhoff principle and the fractional Birkhoff′s equations in terms of RieszRiemann-Liouville fractional derivatives and Riesz-Caputo fractional derivatives are presented respectively.Finally,an example is given to illustrate the application of the results.  相似文献   

9.
In coupled mode,the major problem of boom refueling system is undesirable nozzle loads.An automated load alleviation system(ALAS)is needed to alleviate nozzle loads.In order to simulate dynamic of the system and to validate ALAS,dynamic model is developed.Two models are established,which are the static model and the moving model,named after the two relative states between the fixed boom and the extension boom.Kane method is employed as main method considering system′s multi-body characteristics.D′Alembert′s principle is used to calculate nozzle loads.Simulation is conducted to research the effects of position disturbance and velocity disturbance on nozzle loads.Results indicate that position disturbance plays a more significant role in inducing nozzle loads.A fuzzy control law based ALAS is validated using the formulated model.It is concluded that this model can simulate system dynamic and validate ALAS.  相似文献   

10.
Aiming at the high fuel consumption and use-cost of truck-mounted concrete pump , an energy-saving matching strategy of pumping system is presented and the experimental study is conducted.Since pumping system occupies most resources of engine , the matching strategy between engine and main pump is analyzed to meet the load demand and reduce the engine rational speed drop.The testing method is established to measure the fuel consumption of engine under various working conditions , and the experimental data are analyzed to find the law of the fuel consumption of engine.The system performance can be improved by adjusting the system input value.Finally , the energy-saving matching strategy is established to reduce the fuel consumption of truck for unit workload , which provides a new approach for the energy-saving of truck-mounted concrete pump.  相似文献   

11.
结合企业人力资源的应用背景,提出企业人力资源管理信息系统的设计目标以及系统的体系结构,并设计企业人力资源管理信息系统的解决方案。  相似文献   

12.
通航飞机发动机燃油系统测试台智能化程度普遍较低,测试效率和测试精度低下,严重危及飞行安全。针对某型通航飞机发动机燃油系统测试台设计缺陷和现有不足,采用计算机辅助测试技术和信息管理系统,在原理分析和系统重建的基础上利用特定的编程语言和数据库构建了一套专门的测试软件和管理系统,有效地提高了燃油系统部件的测试效率和测试精度。  相似文献   

13.
田径运动会的编排是一项非常繁琐的工作 ,传统的人工编排操作效率低、准确度低 ,随着体育教学改革的深入 ,田径运动项目的增多 ,为发展高校体育运动 ,提高田径运动会的高科技含量 ,提高教职工、学生的体质 ,结合学校体育工作的实际情况 ,用VisualFoxPro、ASP、VBScript设计了一套高校田径运动会信息管理系统。主要包括网上报名、数据的编排和报表的打印模块。经我院田径运动会的应用表明 ,这一计算机编排系统能有效地减少劳动强度 ,提高数据准确度 ,并能及时输出各种实时数据及报表 ,而且操作简单、灵活、界面友好 ,是高校田径运动会有效的管理软件。  相似文献   

14.
提出了一种在成组技术中应用模糊综合评判理论识别零件几何与工艺特征、进行计算机辅助零件分类的新方法,据此设计了自动分类软件。本法是根据零件本身间的相似性自动分类,不需建立一套分类用编码系统,也不需事先设定假想零件。对不同的分类要求,修改各种输入信息很方便,具有柔性。本文对2300个航空附件回转类零件作了试验分析,讨论了特征抽取,目标类别,权级、权重分配,模糊关系矩阵计算,及自动分类应用软件设计.本软件是在IBM-PC微型计算机上用Fortran-77语言实现的,分类结果满意,自动分类正确率达90%以上。本软件设计方法也适用于设计管理部门.  相似文献   

15.
一个C程序切片系统的设计与实现   总被引:1,自引:0,他引:1  
针对C语言的特点,文中引入了C程序的一些重要概念,诸如数据依赖、控制依赖和程序依赖等。在分析C程序的程序依赖性的基础上,介绍了作者设计并实现的一个C程序切片系统,其中包括系统的概要设计思想,系统中使用的数据结构以及切片生成算法。C程序切片系统不仅可用于产生C程序的切片,而且可用于观察C程序的框架结构和有关变量的多种数据字典。所有这些结果,为C程序的测试、排错与维护提供许多有用的信息,对C程序的并行性检测、波动分析和复杂性度量提供有力的支持。  相似文献   

16.
基于形式概念分析技术,提出了一种验证特征模型和软件架构之间具有可追溯性的方法。该方法分析了特征的组成,定义了特征模型和软件架构的功能表达式,构造了概念格并提出了两个模型之间的映射规则。与一般的模型可追溯性验证方法相比,该方法更适用于复杂度高的模型,最后通过实例研究说明了方法的有效性。  相似文献   

17.
一种新的射频仿真目标位置控制方法与软件研究   总被引:3,自引:0,他引:3  
针对射频目标仿真系统中目标位置的控制,本文通过对国内外目标位置控制的常用方法进行研究,提出一种新的通用目标位置控制方法,该方法适用于任何天线分布的面阵。利用这种新的方法编写了基于三元阵天线阵面的射频仿真目标位置控制软件,实现对多目标在天线阵面上多种轨迹运动下的高速准确的定位,并能实时监视目标的运动状态和运动轨迹。  相似文献   

18.
在面向对象建模的基础上,首先给出了FMS的对象模型,着重研究了FMS动态调度软件自动生成的关键技术。在FMS调度软件的自动生成中,作者提出了运用构造调度指令表的方法,比较好地解决了FMS高度软件自动生存中系统触发唯一高度活动问题,而且将源代码自动生存的顺序,转化为调度摊在调度指令表中的顺序的生存,降低了软件自动生成的难度。文中给出了关键操作的算法,并考虑了死锁的预防,文末给出了应用实例。  相似文献   

19.
JOVIAL语言是美国空军唯一的标准语言。本文根据作者从事军用计算机语言研究的经验,从可靠性、可读性、效率、可维护性、可移植性、可用性、简明性、抽象性以及实现等角度对JOVIAL进行了分析、评价,并将JOVIAL与Pascal、Ada等语言进行了适当的比较,最后指出了作为军用语言的JOVIAL还缺少的语言设施。  相似文献   

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