The objectives of the study were to use finite element computer modeling to investigate the behavior of Wisconsin W wide-flanged prestressed girder ends during and immediately following the strand detensioning process, and to identify solutions for controlling girder end cracking by reducing concrete tension strain or introducing sufficient reinforcement to keep concrete tension strains low and crack width limited.

关键词：电子信息；计算机；模型识别；桥梁裂缝

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关键词：船舶买卖；标准；合同

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关键词：造船指标；经济指标

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关键词：船舶新政；造船

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The SGOS executive and its subsystems have been an integral component of the Shuttle Launch Safety Program for almost thirty years. it is usable (via the LAN) by over 2000 NASA employees at the Kennedy Space Center and 11,000 contractors. SGOS supports over 800 models comprised of several hundred thousand lines of code and over 1,00 MCP procedures. Yet neither language has a for loop. The simulation software described in this paper is used to train ground controllers and to certify launch countdown readiness.

关键词：电子信息；软件；航天；架构

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Flight controllers in NASA s mission control centers work day and night to ensure that missions succeed and crews are safe. The IT goals of NASA mission control centers are similar to those of most businesses: to evolve IT infrastructure from basic to dynamic. This paper describes Mission Control Technologies (MCT), an application platform that is powering mission control today and is designed to meet the needs of future NASA control centers. MCT is an extensible platform that provides GUI components and a runtime environment. The platform enables NASA's IT goals through its use of lightweight interfaces and configurable components, which promote standardization and incorporate useful solution patterns. The MCT architecture positions mission control centers to reach the goal of dynamic IT, leading to lower cost of ownership, and treating software as a strategic investment.

关键词：电子信息；软件；应用程序；飞行控制软件

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This paper outlines an architecture that provides data and software services to enable a set of Unmanned Aircraft (UA) platforms to operate in a wide range of air domains which may include terminal, en route, oceanic and tactical. The architecture allows a collection of command,control, situational awareness, conflict detection and avoidance, and data management elements to be composed in order to meet different requirement sets as defined by specific UA platforms, users, and operating regimes. The architecture discussed is based on a Service Oriented Architecture (SOA) with open standards on the interfaces between elements. Services may include common situational awareness, sense and avoid,weather, data management and flight plan information. Service contracts specify quality of service,interface specifications, service description metadata, security provisions, and governance. Pieces of the architecture have been implemented by MIT Lincoln Laboratory in the form of a Sense and Avoid (SAA) testbed that provides some of the core services. This paper describes the general architecture and a SAA testbed implementation that begins to realize that architecture and quantifies the benefits. The proposed architecture is not directed at a specific program but is intended to provide guidance and offer architectural best practices.

关键词：电子信息；软件；系统；集成

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Air travel has become an indispensable means of transport for enterprises, governments, and more importantly, individuals. In this respect, the demand for new aircraft has always been high over the past decade. Aircraft manufacturing companies manufacture aircraft primarily for airlines, charter operators, and defense organizations. The different types of aircraft that are manufactured can be classified into five types.The Global Aircraft market is expected to grow at a steady rate during the 2012-2016 period. The production of aircrafts has gained momentum with the steady increase in RPK and FTK. Moreover, there has been an increase in the defense budgets of various countries, which is a positive sign for aircraft manufacturers. The Global Aircrafts market was dominated by the Americas in 2012, followed by the EMEA and the APAC regions. The Global market is expected to grow at a CAGR of 6.32 percent during the forecast period.

关键词：航空旅行；个人运输；客机；公务机

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关键词：东南造船；经营模式；管理技术

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Aircraft electrical systems are used to generate, control, and distribute the electrical power throughout the aircraft. The electronic flight instrument integrated in the new generation aircraft completely rely on the electrical power system. Some of the major functions of an aircraft electrical system include controlling and operating essential aircraft systems, operating passenger services systems (such as cabin lighting and operation of in-flight entertainment systems), as well as controlling aircraft flight instrument systems. The products that come under the aircraft electrical systems are auxiliary power units, aircraft batteries, engine-driven generators, motors, power conversion, and distribution systems. Devices used to provide energy to large aircraft other than for the propulsion are known as auxiliary power units. To run the electrical systems of the aircraft, auxiliary power units generally produce 115V at 400 Hz of power. Auxiliary power units provide power through single-phase systems or three-phase systems. Aircraft batteries are the final source of backup power, but the power usage is limited due to the short life of the battery. Engine-driven generators produce power which is used to supply power to the aircraft.

关键词：飞机；电气系统；飞机电池；发电机；电动机

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