飞机飞行状态下燃油惯性特性计算方法研究

大型飞机的燃油惯性特性对于飞机的设计及飞行安全有着重要的影响.针对现有大型飞机燃油惯性特性计算方法不能准确仿真实际耗油过程,计算结果与实际差异大等问题.为解决上述问题,通过研究飞机燃油系统内燃油的流动规律,构建了流动规律的窜油模型,并给出模型的燃油惯性特性计算方法.经理论分析及仿真计算表明,窜油模型更加真实地仿真了飞机耗油过程中燃油在油箱各腔体之间的流动情况,利用窜油模型进行燃油惯性特性计算,并可以准确预测燃油数量,能更好地满足工程需要.     

超声波流量计在飞机燃油流量测试中的应用研究

燃油系统输油流量测试是飞机燃油系统地面模拟试验的一项重要内容;由于试验油箱内部的各管路与真实飞机油箱管路的布置是一致的,不适合在油箱内的狭小空间安装涡轮流量计,并且会破坏管路流阻特性;由于使用传统油箱油量标定的方法进行输油流量测量耗时耗力,所以需要采用一种新的技术或测量方法来完成油箱输油流量的测量;超声波流量计体积小,不会破坏输油管路流阻特性,防爆等级也符合试验要求;对超声波流量计在浸油状态下测试进行可行性分析,将超声波流量计在飞机燃油系统试验中实现创新性应用;通过试验证明了超声波流量计在飞机燃油流量测试中发挥了重要作用,并且首次将超声波流量计应用到飞机试验油箱内部输油管路的流量测试中,这对飞机其他系统的流量测试和飞机机上排故试验起到了重要作用。     

电动驶向未来

让耗油鬼都闪一边．这些混合动力机器将载我们到未来。 汽车制造商们正把自己逼进一个死胡同.世界上超过半数以上的人口都居住在城市，可如何满足城市驾驶者的需求，     

空中进攻作战模拟出动计划设计方法研究

出动计划是空中进攻作战模拟中数学模型设计的重要内容。目前有关的研究都是以火力打击计划为主，并且集中于出动计划理论问题和技术系统的顶层设计层面，在贴近实际方面还有待于进一步深化。该文提出的空中进攻作战出动计划设计方法，将空中信息进攻力量与空中火力进攻力量融为一体进行计划，提出了空中进攻作战出动计划的设计原则和设计步骤，重点设计了火力打击飞机和信息作战飞机的出动编队计算方法、弹药／器材携载计算方法，使整个计划更加完整，更符合现代空中进攻作战的实际。     

飞机油箱燃油量体积特性计算与油量测量仿真

飞机油箱体积特性数据库是油量测量计算的基础,直接影响油量测量的精度;针对目前将油箱模型离散化为有限规则单元,再进行叠加计算燃油体积方法存在的通用性差与精度低的不足,文章根据飞机油量传感器测量高度、飞行姿态以及三轴加速度信息,确定出油平面,并以此作为分割平面,通过CATIA二次开发实现油箱燃油体积特性数据库自动生成;根据特性数据库的特点与机载数据要求,采用后向试探法对数据库进行压缩与优化;模拟飞机油量测量过程,设计油量测量仿真软件,仿真结果表明;油量计算的相对误差小于1%,按所采用方法计算的数据库能达到工程要求。     

基于计算机视觉的飞机燃油非接触式测量系统

为了实现飞机在任意飞行姿态下燃油量的测量,提出了一种新型的飞机燃油测量 系统。首先采用基于计算机视觉的非接触性液位感测技术,测得油箱中油位高度。然后采用 CAD 技术对油箱建模,实现了飞行姿态误差的修正。实现在油箱外对当前液面进行实时观测和 三维重建,无需对油箱内燃油通电,避免了传统测量方式的电磁干扰、电路磨损问题,提升了 燃油系统的安全性和可靠性。实时精确地测量剩余燃油量,对飞机的加输油控制、系统状态监 控、故障诊断隔离等功能具有重要意义。该油量测量方式与传统方式相比具有数字化、智能化 程度高、抗干扰能力强、可靠性高等优点。     

提高无人作战飞机协同作战能力的关键技术

简要分析了提高无人作战飞机协同作战能力所涉及的几个关键技术问题。从国外无人作战飞机协同作战相关战例研究入手,对有人机对无人机飞行导航系统和战斗机交战管理2个典型协同战例进行描述;重点分析了多无人作战飞机协同作战、有人机与无人作战飞机协同作战两种作战样式中的关键技术问题;最后介绍了无人作战飞机协同作战的两种典型应用。     

基于电化学原理的飞机燃油箱氧浓度机载测量技术

飞机燃油箱惰化系统属飞机燃油系统设计中重要的分系统，为了准确评估燃油箱惰化系统的功能与性能，需要根据飞机实际使用剖面和惰化系统设计特点确定适用的飞行测试方法。提出了一种基于电化学原理的飞机燃油箱氧浓度机载测量方法，用于飞行实时测量运输类飞机油箱内无油空间或惰化管路的气体氧浓度，并对飞行中的实际影响因素进行模拟分析。经过分析飞行实际环境影响因素、关键传感器匹配性以及原理样机的试验验证等工作，将燃油箱氧浓度机载测量技术转化为专用的飞机燃油箱氧浓度机载测量系统，并通过了飞行实测考验。试飞结果表明，该项技术能够实时准确测量运输类飞机各种状态下的燃油箱氧浓度，满足飞机燃油箱惰化系统的效能评估要求。     

基于飞机训练模拟器的战役仿真

本文基于飞机训练模拟器，建立了战役模拟仿真系统，给出了系统软件的基本组成，着重介绍了作战推演过程模块的实现手段和方式以及统计评估模块的设计算法。     

基于DIS的防空训练空情保障系统

该文以新三打三防训练模拟为背景，建立了多种虚拟靶标，如巡航导弹、作战飞机、武装直升机的仿真模型，包括物理模型和决策模型，在此基础上，基于分布式交互仿真技术（Distributed Interactive Simulation,DIS）开发了一个用于防空训练模拟的空情保障系统。本文主要介绍了空情保障系统的模型建立、数据管理和系统集成方法。     

Aeroplane detection in very-high-resolution images using deep feature representation and rotation-invariant Hough forests

This letter proposes a processing chain for detecting aeroplanes from very high-resolution (VHR) remotely sensed images with the fusion of deep feature representation and rotation-invariant Hough forests. First, superpixel segmentation is used to generate meaningful and non-redundant patches. Second, deep learning techniques are exploited to construct a multi-layer feature encoder for representing high-order features of patches. Third, a set of multi-scale rotation-invariant Hough forests are trained to detect aeroplanes of varying orientations and sizes. Experiments show that the proposed method is a promising solution for detecting aeroplanes from VHR remotely sensed images, with a completeness, correctness, and F-measure of 0.956, 0.970, and 0.963, respectively. Comparative studies with four existing methods also demonstrate that the proposed method outperforms the other existing methods in accurately detecting aeroplanes of varying appearances, orientations, and sizes.     

基于刚粘塑性有限元法的定子挤压工艺仿真

该文讨论了油泵定子传统成形方法的局限性,提出了采用温挤压工艺成形油泵定子的新工艺,为验证新工艺的可行性以及降低产品开发周期与模具成本,对油泵定子温挤成形过程的有限元仿真分析,优化了成形工艺及模具参数,通过与物理试验比较,验证了数值模拟分析的准确性。研究结果表明：①采用新工艺可以成形出机械性能好、材料利用率高的油泵定子;②采用数值模拟优化后的坯料,可以成形出锻件质量好,综合机械性能高的产品;③生产试验表明,有限元数值模拟是分析金属塑性成形问题的一种先进的、有效的方法,采用数值模拟优化后的方案对锻件进行生产试制,可以获得成形质量好的锻件,且模拟结果与生产试制结果一致。     

Aeroplane detection from high-resolution remotely sensed imagery using bag-of-visual-words based hough forests

ABSTRACT

This paper presents a rotation-invariant method for detecting aeroplanes from high-resolution remotely sensed images. First, a superpixel-based strategy is proposed to generate salient and distinctive feature regions. Second, a bag-of-visual-words representation is adopted to characterize spectral statistical features of feature regions. Third, a multi-scale rotation-invariant Hough forest with embedded scale factors and orientation information is trained to cast rotation-invariant votes for estimating aeroplane centroids. Quantitative evaluations on the images collected from Google Earth service show that a completeness, correctness, quality, and F₁-measure of 0.980, 0.973, 0.954, and 0.976, respectively, are obtained. Comparative studies with five existing methods also demonstrate the superior performance of the proposed method in accurately and correctly detecting arbitrarily-orientated and varying-sized aeroplanes.     

Opportunistic planning for a fleet of transportation robots

The Dynamic Transportation-Planning Problem (DTPP) embodies a class of real-world applications that involve the reactive routing and scheduling of a fleet of vehicles in response to dynamically changing transportation demands. Examples include mobile robots in a warehouse, taxis in an urban road network, or aeroplanes for medical evacuation. In contrast with the Vehicle Routing Problem, for which a plethora of techniques is available, few approaches exist that permit the efficient deployment of a large number of vehicles in a changing environment. This paper highlights the characteristic features of the problem, reviews possible approaches and existing techniques, and proposes a heuristic solution to the DTPP using a Blackboard-based approach. The resulting application is an intelligent transportation planning system (ITPS) for a fleet of automated robot taxis, based on the generic assumption-based truth maintained Blackboard shell (GATMBS) and comprising traffic simulation models as well as various monitoring and problem-solving strategies for assignment and routing. The Blackboard architecture supports the dynamic alteration of planned routes in response to changes in traffic conditions and passenger requests. A prototype of the ITPS has been validated in simulation using a small fleet of robot taxis with randomly generated road networks, background traffic load, and passenger requests.     

黑油模型新解法器的研制

引言 大型稀疏线性代数方程组的迭代求解是当前数值代数研究领域的核心问题之一,许多成熟的算法已经在大规模科学与工程计算中产生了重要作用.具体到油藏数值模拟软件,线性代数方程组的求解占据了超过80%以上的计算量,故其性能好坏直接决定了油藏模拟的速度和质量,其中由黑油模拟形成的稀疏线性代数方程组迭代     

船舶分油机模拟器设计与实现

针对分油机控制系统的仿真设计落后于当前先进控制系统的问题,提出了一种以Alfa Laval S系列分油机的EPC-60控制系统为母型的分油机模拟控制系统。介绍了分油机模拟器的整体结构,设计了以ARM为主控元件的仿真控制箱,实现了网络通信、液晶显示、按键扫描等功能。采用Visual C#编程语言在PC机上设计出仿真控制界面。实验结果表明：基于EPC-60为母型控制系统的分油机模拟器具有功能全、运行稳定、和实物相似度高的优点,能够实现轮机教学实验和海员培训的功能。     

Road warriors — armoured and ready?

The road warrior has become a veritable moving office, but an office nonetheless that needs the same protection as its more traditional sibling. The same access control and authentication procedures apply. The same data has to be secured and protected. This data is routinely accessed at docking stations in hotels, trains, aeroplanes, homes offices, and quite literally, on the side of the road. While many of the bigger organizations have some pretty sophisticated security solutions in place, smaller ones may have little or no control over the way their roving employees access the company’s information infrastructure.     

福建海域溢油应急处置辅助决策系统设计和实现

海上溢油污染问题目前已成为国际公认的危害性极大的环境污染问题之一。建立相关海域溢油应急处置辅助决策系统,研究海上溢油漂移的数值预报机理,开发海上溢油应急处置模拟训练系统和海上溢油应急处置决策支持系统是十分必要的。本文提出了福建海域溢油应急处置辅助决策系统设计思路和实现技术路线。     

Exact solution for a two-type customers retrial system

Based on a real problem connected with the landing of aeroplanes we examine a special queuing system, where peculiar conditions prevail. In such systems a request for landing can be serviced upon arrival if the system is free. When other planes are using the runway or waiting to land, the entering plane has to start a circular manoeuvre and can put its further requests when it comes to the starting point of its trajectory. Because of possible fuel shortage it is natural to use the FIFO rule. The article describes a more generalized form of such a system. This serves two types of customers, but one of them is accepted only if the system is in free state. Together with generating functions of probabilities we also give the condition of ergodicity. Theory is underpinned by numerical investigation.     

某型飞机机翼油箱输油仿真研究

研究飞机机翼油箱优化控制问题,燃油系统在飞机上是一个非常庞大而且复杂的系统,传统增压泵输油方案存在重量大、功率需求高的缺点.针对传统方法对燃油系统仿真研究建模复杂、耗时长的缺点,提出了利用油箱间增压压力差向消耗油箱输油的输油方案.利用流体仿真软件FLOWMASTER对燃油系统进行建模.对所建燃油系统模型进行仿真,结果表明,燃油系统各项性能指标能够满足系统需求,验证了所提方案的正确性,为改进和优化燃油系统设计提供了新思路和方法.