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1.
Dirk Bühler 《Mauerwerk》2020,24(1):26-36
The Rank construction company and the introduction of brick vaults in Munich after 1945 The construction of vaults without scaffolding with thin bricks has a centuries‐old tradition, particularly in Spain and Italy. Since the beginning of the 19th century, it has been successfully spread mainly on the American double continent. The Rank Brothers construction company in Munich is known to date as one of those construction companies that began building with concrete in its home city very early on. New investigations, which were made possible above all by the provision of archive material by Paul Basiner, now point to an additional focus of this company's work. The architects and engineers of the company had been also able to familiarise themselves with this traditional Spanish brick‐vaulted construction method via the branch office in Spain, which was established from 1911 on. This knowledge was particularly in demand in the years following World War II, when the destroyed vaults had to be rebuilt with simple means and low material consumption. Together with Carl Sattler, who had become acquainted with similar construction methods in Italy, brick vaults were initially used to complete the construction of the Landeszentralbank in Munich. In the following years, Rank was able to provide many buildings in and around Munich with brick vaults. It was not until the 1960s that this construction technique went out of fashion and was thus somewhat forgotten.  相似文献   
2.
In this article, a decentralized optimal tracking control strategy is proposed for a class of nonlinear systems with tracking error constraints by utilizing adaptive dynamic programming (ADP). It should be noted that ADP technology cannot be directly used to solve decentralized optimal tracking problem of large-scale interconnected nonlinear system with nonzero equilibrium points, since that an infinite domain performance index function may result in an unsolvable solution. In addition, by introducing a smooth function, the constrained tracking error is transformed into an unconstrained one. Then, the error dynamics and a new infinite domain performance index function are designed, such that ADP technology can be used. Following the designed performance index function, the tracking error can be ensured within a small neighborhood of zero. Finally, the feasibility and the effectiveness of the proposed decentralized optimal control scheme are verified through two simulation examples.  相似文献   
3.
介绍了一种大轮拖底盘涂装线控制系统,采用西门子PLC、PROFIBUS、WINCC等控制技术,实现了涂装线的集中监测和分散控制,解决了涂装线生产任务高、工艺工位多、设备分布分散的问题,提高了轮拖涂装线的自动化水平。  相似文献   
4.
5.
Interlock failure of combined sheet pile walls In addition to multiple combinations of king piles and intermediate sheet piles the installation method of combined sheet pile walls can differ as well. The installation has to adapt to the boundary conditions of the construction work considering soil conditions, profile and interlock system, interlock protection, driving equipment, driving assistance etc. Despite the established construction of combined sheet pile walls interlock failure occurs. In this paper, the installation aspects of combined sheet pile walls in northern Europe are compiled and analyzed for the occurrence of interlock failure.  相似文献   
6.
Expansion of the branch channel to Salzgitter from SKS‐km 3,550 to 14,918 The branch channel to Salzgitter will be extended to the waterway category Vb in the next years. This will enable inland waterway vessels with a width of 11,45 m and a loaded draft of 2,80 m to run it without limitations. The reaches Wedtlenstedt and Üfingen will be extended in most areas to a trapezoidal cross section with a width at water level of 36,90 m and a water depth of 4,00 m. The exit basins of the locks will be extended on one side. Overall about 1 000 000 m2 of soil will be moved. About 300 000 m2 of clay sealing and 460 000 m2 of rip‐rap will be installed. Three culverts have to be replaced by new constructions to adapt to the new cross section of the channel. In addition two bridges will be modified to allow for a clearance of 5,25 m. At present the plan approval procedure is carried out. It is expected to achieve the plan approval order in 2017. The construction is planned to start in 2018. Completion is scheduled for 2024.  相似文献   
7.
贺新良 《山西建筑》2007,33(29):199-200
阐述了执行力是企业市场竞争取胜的根本保证,从人员、决策制度、监督考核等方面分析了当前影响企业执行力的主要因素,深入地探讨了提升企业执行力的途径,以提高企业的执行力,从而保证企业的生存和发展。  相似文献   
8.
工程量清单计价的合同贯穿在建设工程的实施过程中,如何在计价方式、风险约定、合同备案、合同的履行等方面进行管理,有利于《建设工程工程量清单计价规范》的推广和执行。  相似文献   
9.
姜平 《世界建筑》2002,(11):18-23
回顾评介SOM的发展进程及近期作品。  相似文献   
10.
王晓军  邵蓉  孙枫然 《煤气与热力》2004,24(12):690-691
对集中生活热水供应方式和各用户使用小型燃气热水器生活热水分散供应方式进行了经济性分析。集中热水供应为供暖期采用供热锅炉和生活热水换热机组(设在热力站)供应生活热水.非供暖期采用小型热水锅炉和生活热水换热机组供应生活热水。  相似文献   
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