机场容量评估中仿真飞机流的设计与实现

为了提高机场及终端区容量评估的计算精度,以机场实际航班运行数据库为基础,讨论了仿真飞机流的数据构成,提出了飞机流的仿真思路、模块结构设计和仿真流程,构建了飞机流生成模型.为保证航空器运行的"单列不可超车"性和最小运行间隔要求,运用数理统计方法,确定了机头距服从移位负指数分布的假设检验,并采用素数模积式发生器和逆变法保证了仿真过程的随机性,编程实现了随机飞机流的仿真.算例仿真结果表明,此模型是可行的,实现了统计意义上机头距概率分布类型的优化,为容量仿真评估提供了较为理想且准确的仿真飞机流.     

突发大规模需求下铁路军事运输保障研究

以"5·12"汶川地震为背景,分析了突发大规模需求下铁路军事运输保障的特点及要求,提出了应急铁路军事运输保障的具体对策,如建立健全铁路军事运输指挥机制、制订输送保障运行计划等,对铁路军事运输部门提高突发大规模需求情况下的运输保障能力具有借鉴意义.     

西福河大桥T梁架设工艺

文章以广东省道S119线西福河大桥工程施工为例,介绍采用军用六四式轻便杆件现场设计和组装双导梁架桥机跨河架设35～40mT梁的工艺技术,此技术不仅可降低架梁费用;取得较好的经济效益,而且能克服设备进场难和交通干扰等问题。     

终端区飞机排序的混合人工鱼群算法

为了保障飞行安全,对终端区着陆飞机进行有效的排序,建立了以航班延误总时间最小为目标函数的规划模型,以人工鱼群算法为基础,融合了遗传算法的选择操作和模拟退火算法的依概率接受的思想,形成混合人工鱼群算法,对着陆飞机排序问题进行了仿真计算,并与先到先服务算法、模拟退火算法以及蚁群算法进行了对比研究。仿真结果表明:与先到先服务相比,使用人工鱼群算法使得单跑道、双跑道延误分别减少了9·3%和48·0%,计算时间小于3s;与蚁群算法和模拟退火算法相比,求解的延误与时间最小,因此,提出的混合算法可行。     

军事通信系统的效能评估初探

随着信息技术的发展,军事通信系统的构成日益复杂,规模日益庞大,战术技术指标更加复杂多样。以往那种仅凭经验作定性分析的效能评估方法已很难对现有军事通信系统的效能做出科学准确的评估。论文从军事通信系统的功能划分着手,构建了军事通信系统效能评估的指标,并对军事通信系统的效能评估方法做了初步探讨。     

Effective aircraft maintenance schedule adjustment following incidents

In the real world, planned aircraft maintenance schedules are often affected by incidents. Airlines may thus need to adjust their aircraft maintenance schedules following the incidents that occur during routine operations. In tradition, such aircraft maintenance schedule adjustment has been performed manually, a process which is neither effective nor efficient, especially when the problem scale is large. In this study, an aircraft maintenance schedule adjustment model is developed, with the objective of minimizing the total system cost, subject to the related operating constraints. The model is formulated as a zero-one integer program and is solved using a mathematical programing solver. The effectiveness of the model is evaluated by application to a case study using data from an aircraft maintenance center in Taiwan. The test results show the proposed model, as well as the scheduling rules abstracted from the results are useful for the decision maker to adjust good maintenance schedules.     

A three-stage least squares approach to the analysis of airline strategies for aircraft size and airline frequency on the north Atlantic: an airline case study

In response to increasing demand, airlines may increase capacity by increasing the frequency of flights or they may choose to increase aircraft size. This may yield operating cost economies. If the airports they operate from are capacity constrained, they will be limited in the extent that they can change frequency which will limit their ability to compete with the number of frequencies offered. This article focuses on this trade-off and pays particular attention to the practices of a specific airline. Conclusions are offered on the impact of inter alia competition, changes in aircraft technology, 9/11 and the impact of slot constraints. It appears that changes in size are more important than frequency, which is consistent with the presence of slot constraints and there is a significant impact of competition. As the concentration of carriers increases, so aircraft size falls. 9/11 also has a significant impact on traffic whereas the introduction of the Boeing 777, as an illustration of a change in technology, does not.     

保障高原军用公路畅通手段的探讨

阐述了影响高原军用公路安全的各种主要自然灾害类型与形成的原因和特点,从工程技术方面提出了泥石流、滑坡、溜砂、水毁的防治方案与对策,并从Et常管理方面对保障高原军用公路畅通的各种手段进行了探讨。有助于高原军用公路保持通畅状态。     

战时铁路军事运输态势推演研究

在对战场态势推演相关理论和态势推演系统结构研究的基础上,分析了应急作战条件下铁路军事运输态势推演的需求,研究了战时铁路军事运输态势推演系统的体系结构,为未来我军研究应急作战铁路军事运输态势推演系统提供理论参考。     

机场水泥混凝土道面飞机荷载影响深度分析

荷载影响深度是研究机场道面沉降的重要参数。本文采用ABAQUS有限元软件为平台,针对4C、4D和4E等级机场分别提出了相应的＂道面结构-飞机荷载＂组合形式,并借鉴公路研究思路,通过对比基础内的荷载应力与自重应力,分别采用σZ/σB=0.1和σZ/σB=0.2两种判断标准,得到了不同土质、不同等级机场条件下的基础影响深度。研究表明,不同土质对基础影响深度的影响非常小;不同等级机场的基础影响深度相差可达100%。