-
1811.基于北斗卫星载波相位平滑伪距的列车定位方法
[铁路、船舶、航空航天和其他运输设备制造业] [2014-05-15]
随着我国北斗卫星导航系统的建设,北斗卫星已逐步具备应用于列车定位的能力.列车在铁路线上存在轨道占用区分的需求,北斗民用伪距定位对并行股道占用情况难以精确定位识别.采用北斗实时载波相位定位精度高,但需近距离基准站的差分信号和模糊度解算,不利于大范围内的实时应用.因此,本文结合北斗卫星伪距的无模糊度和载波相位的高精度特点,提出一种基于北斗载波相位平滑伪距的列车定位方法.该方法首先利用北斗组合相位伪距法探测与修复载波数据周跳,并采用修复后的载波相位数据平滑伪距.文中推导北斗载波相位平滑伪距的原理,分析不同平滑方法的特性和对应的噪声检验公式.采用实测数据计算两种平滑方式得到的结果表明:本文提出的方法能够有效快速探测与修复周跳,平滑伪距精度优于0.2m,满足北斗导航系统在铁路列车定位中的精度要求.
关键词：列车定位；北斗卫星；相位平滑伪距；周跳探测
-
1812.地震激励下高速列车动态响应与运行安全边界研究
[铁路、船舶、航空航天和其他运输设备制造业] [2014-05-15]
为研究地震对高速列车动态响应与运行安全的影响,建立地震激励下车辆-轨道耦合动力学模型,地震波被简化为周期性的横向正弦波加入车辆轨道仿真模型中.基于仿真计算,对地震作用下高速列车的动态响应、脱轨机理及运行安全边界进行详细地分析和讨论,给出地震下高速列车安全运行及脱轨边界.分析结果表明:地震所引起的轨道结构大幅横向振动对高速列车的安全运行影响极大；横向地震波激励下,车轮与钢轨频繁地发生分离、车轮的大幅度抬升和车辆激烈的横向滚摆运动是造成高速列车脱轨的主要原因.
关键词：脱轨；地震；高速列车；车辆-轨道耦合动力学；脱轨准则
-
1813.基于随机机会约束规划的内燃机车减排技术评价优化模型研究
[铁路、船舶、航空航天和其他运输设备制造业] [2014-05-15]
利用不确定规划理论,提出基于随机机会约束规划的机车减排技术决策评价优化模型及其算法.模型的目标函数为期望运营成本最小,决策变量为减排技术种类及减排效率,约束条件为排放污染物致癌风险及对健康影响情况不超过一定概率等.将随机模拟和智能算法相结合,设计求解模型的双层混合智能算法,并利用此算法对算例进行求解,说明模型和算法的可行性和有效性.
关键词：机车减排；技术评价；优化模型；随机机会约束规划；混合智能算法
-
1814.全球商用飞机碳刹车盘市场报告（2014-2018年）
[铁路、船舶、航空航天和其他运输设备制造业] [2014-04-26]
Modern, lightweight, and fuel-efficient aircraft are now in demand and aircraft manufacturers are trying hard to meet this demand. The carbon brake, which is a substitute for the traditional brake, is lightweight and has high energy absorption capability. The cost of carbon brakes used to be high; therefore, steel brakes were used in small aircraft and carbon brakes were used in large aircraft. In recent years, there have been a lot of improvements in the carbon brake technology, making carbon brakes cost competitive with steel brakes. The Global Commercial Aircraft Carbon Brake market is expected to witness steady growth due to the presence of some emerging trends that are expected to negate the impact of the challenges to a certain extent. One such trend is the increasing demand for low-maintenance carbon brakes. Another trend is the increasing focus on R&D.
关键词：碳刹车；市场状况；飞机
-
1815.全球无人机机载遥感市场报告（2014-2018年）
[计算机、通信和其他电子设备制造业,铁路、船舶、航空航天和其他运输设备制造业] [2014-04-20]
The Global UAV Airborne Remote Sensing Technology market is expected to grow at a moderate rate during the period 2013-2018. The majority of the demand for remote sensing products was from the Americas, which accounted for 64-66 percent of the market revenue in 2013. The APAC and the EMEA regions are experiencing promising growth, and this trend is expected to continue during the forecast period. The Global UAV Airborne Remote Sensing Technology market is expected to reach US$2.86 billion by 2018, growing at a CAGR of 5.39 percent during the forecast period.
关键词：遥感；材料对象；信息；设备收集；空间（卫星）；飞机
-
1816.环球飞行管理系统市场报告（2014-2018年）
[信息传输、软件和信息技术服务业,铁路、船舶、航空航天和其他运输设备制造业] [2014-04-19]
The electronic systems used in spacecraft, aircraft, and artificial satellites are known as avionics systems. Avionics systems include the flight management system, navigation systems, and communication systems. A flight management system is a device that performs the work that was originally carried out by navigators and flight engineers. The prime function of flight management systems is in-flight handling of the flight plan. The systems have various sensors that help the devices locate the position of the aircraft and guide the pilot according to the flight plan.
关键词：航天器；飞机；人造卫星；航空电子设备系统；飞行管理系统；导航系统；通信系统
-
1817.全球航空航天复合材料市场报告（2014-2018年）
[铁路、船舶、航空航天和其他运输设备制造业] [2014-04-15]
This report covers the present scenario and the growth prospects of the Global Aerospace Composites market for the period 2014–2018. The report considers 2013 as the base year and provides data for the trailing 12 months. The market size was calculated on the basis of the total global revenue generated from the shipment of composite materials for the Global Aerospace market. The report also presents the vendor landscape and a corresponding detailed analysis of the top four vendors in the Global Aerospace Composites market. In addition, it discusses the major drivers that influence the growth of the Global Aerospace Composites market. It also outlines the challenges faced by the vendors and the market at large, as well as the key trends that are emerging in the market.
关键词：复合材料；飞机制造；高的强度；重量比；抗疲劳耐力；耐腐蚀性；耐磨性；展性
-
1818.美国宇航局空间通信网络集成
[信息传输、软件和信息技术服务业,计算机、通信和其他电子设备制造业,铁路、船舶、航空航天和其他运输设备制造业] [2014-04-03]
Salient features of the Integrated Network include (a) a central system element that performs service management functions and user mission interfaces for service requests; (b) a set of common service execution equipment deployed at the all stations that provides return, forward, and radiometric data processing and delivery capabilities; (c) the network monitor and control operations for the entire integrated network are conducted remotely and centrally at a prime-shift site and rotating among three sites globally (a follow-the-sun approach); (d) the common network monitor and control software deployed at all three network elements that supports the follow-the-sun operations.
关键词：通信；宇宙通信；网络控制；数据处理；成本
-
1819.北极地区通信小卫星（ARC-Sat）
[计算机、通信和其他电子设备制造业,铁路、船舶、航空航天和其他运输设备制造业] [2014-04-03]
Organizations are unable to support near‐ and mid‐term Arctic operations to include: Humanitarian Response, Environmental Response, International Search & Rescue (SAR), and Counter‐Trafficking (to include WMD).
关键词：通信；小卫星技术；通信卫星；北极地区
-
1820.机场移动航空通信系统干扰对机场的辐射模式特性的影响
[铁路、船舶、航空航天和其他运输设备制造业,计算机、通信和其他电子设备制造业] [2014-04-03]
In this study, the cumulative interference power distribution at low earth orbit from AeroMACS transmitters at the 497 major airports in the contiguous United States was simulated with the Visualyse Professional software. The dependence of the interference power on the number of antenna beams per airport, gain patterns, and beam direction orientations was simulated. As a function of these parameters, the simulation results are presented in terms of the limitations on transmitter power required to maintain the cumulative interference power under the established threshold.
关键词：通信；无线辐射模式；移动通信系统；仿真
027-87841330