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991.
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993.
该装置结构简单,实用性强,适用性广,便于拆装,易于操作,成本低廉,功能齐全,设计人性化.集座椅、高空缓降、担架、登高梯、运送小车等功能于一体.主要适用于中低层建筑在火灾或小型地质灾害下的逃生救援. 相似文献
994.
《Bautechnik》2017,94(8):526-534
Repair of the left chamber of the Neckar lock Aldingen and of the upstream boat landing From 1921 to 1968, the Neckar was extended over a length of approximately 200 km to a federal waterway. The lock was built as part of the water retaining structure in the course of the canalisation of the Neckar from the 1930s, interrupted by the Second World War, until the end of the 1950s. The chambers of the double lock have a length of 110 m and a width of 12 m, the head is 3.60 m. The article describes the planning of a major overhaul of the left chamber of the Neckar lock Aldingen as well as of strengthening measures of the upstream boat landing such as: refurbishment of the chamber (concrete facing) and lock heads, new construction of the lock‐gates, replacement of the drives, as well as of the electrical systems and control technology, replacement of the slope revetment in the upstream boat landing (riprap), furthermore construction of a new pile berth with an access bridge. The planning is based on a study on the standardisation of the extension of the Neckar locks measures, prepared by the Federal Waterways Engineering and Research Institute and the Specialised Unit of Mechanical Engineering Southwest, besides being based on the technical body of rules. The article concludes with an insight into the ongoing construction works. 相似文献
995.
随着国家信息化和宽带中国战略的实施,三大运营商均提出了大规模的站址需求,铁塔公司面临着一方面要满足客户站址建设需求,另一方面要解决选址建设难度,确保站址落地.铁塔公司需要充分发挥掌握的百万存量资源、归集3家运营商需求的优势,力争在站址规划满足率、共享率以及落地率方面达到行业领先水平,同时积极将铁塔等移动通信基础设施纳入城乡专项规划,确立移动通信基础设施的公共基础设施地位,实现规划站址的落地.本文就铁塔公司通信基站专项规划的规划思路进行了探讨,尤其为确保规划与需求吻合、与建设一致提出了详细的规划方法和步骤,同时从铁塔公司长期的站址储备提出了站址预规划空洞选址思路,为更好的化\"被动需求\"为\"主动引导\",提升资源利用率. 相似文献
996.
Space mission design places a premium on cost and operational efficiency. The search for new science and life beyond Earth calls for spacecraft that can deliver scientific payloads to geologically rich yet hazardous landing sites. At the same time, the last four decades of optimization research have put a suite of powerful optimization tools at the fingertips of the controls engineer. As we enter the new decade, optimization theory, algorithms, and software tooling have reached a critical mass to start seeing serious application in space vehicle guidance and control systems. This survey paper provides a detailed overview of recent advances, successes, and promising directions for optimization-based space vehicle control. The considered applications include planetary landing, rendezvous and proximity operations, small body landing, constrained attitude reorientation, endo-atmospheric flight including ascent and reentry, and orbit transfer and injection. The primary focus is on the last ten years of progress, which have seen a veritable rise in the number of applications using three core technologies: lossless convexification, sequential convex programming, and model predictive control. The reader will come away with a well-rounded understanding of the state-of-the-art in each space vehicle control application, and will be well positioned to tackle important current open problems using convex optimization as a core technology. 相似文献
997.
As the backbone of Communications, Navigation and Surveillance Systems for Air Traffic Management (CNS/ATM), Automatic Dependent Surveillance-Broadcast (ADS-B) is a surveillance technology and digital-technology enabler relying on the Global Navigation Satellite System (GNSS). The onboard ADS-B Out system broadcasts the aircraft’s real-time digital information such as position and ground speed periodically (every 0.5–2 s), which is more frequent than the radar system. Taking this advantage, situational awareness and flight efficiency can be highly improved. In this paper, a novel heuristic search method based on ADS-B is proposed for the Aircraft Landing Problem (ALP) with the objective of reducing flight time while maintaining the time separation standards mandated by the International Civil Aviation Organization (ICAO). The recorded ADS-B data in Shanghai Hongqiao and Pudong international airports are adopted to demonstrate the performance of the proposed method. Results show that there is an obvious decrease in the total flight time. Besides, the heuristic search method can achieve continuous and real-time ALP updates, satisfying the requirements for air traffic control. While highlighting ADS-B-based applications, this study also provides some basic implications for the updated model in air traffic management. 相似文献
998.
主要阐述了消防联动系统中防火卷帘门、非消防电源、电梯迫降、气体灭火控制等方面的逻辑关系,并根据工程实际情况对逻辑关系中的一些问题提出了自己的看法. 相似文献
999.
本文对高速线材轧制工艺过程中的强制水冷过程进行了分析,并在此基础上设计了一套控制系统。该系统根据穿水冷却过程的特点对系统功能进行了层次划分,在上层采用神经网络模型进行自学习分类,并将训练得到的权值用于控制模型,以得到底层控制系统所需的设定值,底层系统依设定值进行有效控制,从而得到较好的金相组织。 相似文献
1000.
载人登月软着陆中手动控制制导方案研究 总被引：1，自引：0，他引：1
针对载人登月软着陆的接近段和着陆段,研究手动控制重新选址方案。首先引入了载人登月阶段划分,建立了登月舱动力学模型,然后对电视制导和舷窗制导2种手动控制选址方案进行了比较。电视制导方案中,宇航员能够直接在视场内选择新的着月点,并由自动控制系统实现对目标的制导;传统的舷窗制导要求宇航员全程参与控制,主要约束包括手动控制的延迟以及舷窗的视线范围,并且每次手动调节量有限。对2种制导方案的仿真结果表明,电视制导由于不受视线角约束,着月点可调整范围大于舷窗制导。同时电视制导对姿态机动的要求更高。并且宇航员重新选址操作进行得越早,着月点可调整范围越大。 相似文献