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The core concrete filling is the key to the construction of concrete-filled steel tubes arch bridge. This paper presents a control system for the workability of core self-consolidating concrete with high robustness and its test methods which aim at tackling the problems of a shortage of high-quality raw materials and a wide temperature difference during placing in the construction of Lalin Railway Zangmu Bridge in the Qinghai-Tibet Plateau. A new type of high robustness polycarboxylate water reducer was developed based on the hydrophobic associating and sustained or controlled release high polymer molecules construction. This new type of polycarboxylate water reducer improved the workability robustness of the core self-consolidating concrete and weakened its susceptibility to variable raw materials temperatures and other factors compared with conventional polycarboxylate water reducers which has satisfied the demand of design and construction well. [ABSTRACT FROM AUTHOR]

As the basis of the research on reducing wake vortex separations, numerical simulation and constructing of fast-models for simulating wake vortex have become the focus of many international ATM research institutes. In the research field of wake vortex numerical simulation, the formation, evaluation and decay of wake vortex are calculated based on RANS, LES or DES methods. These data can help to reveal the regulation of wake vortex, and can provide basic foundation for constructing wake vortex models. In the field of fast simulation of wake vortex, Some organizations have done many theoretical researches on the formation and dissipation of wake vortex, attempting to deduce the behavioural characteristics of wake vortex by establishing complex mathematical models, including CROW instability, Greene model, APA model, TDAWP model, D2P model and the three-phase decay model, etc. The research status quo is analyzed and the key works in the next phase are also provided. [ABSTRACT FROM AUTHOR]

In order to evaluate the navigation ability of required navigation performance (RNP) for the newly designed civil aircraft, the lateral and vertical flight error model were developed for the track to fix(TF) segment and the radius to fix(RF) segment. Through converted geographic coordinates, the deviation between the actual flight path and the defined path was calculated. The actual flight of an airport was taken as an example to analyze the airworthiness of the new civil aircraft. The flight deviation was statistically analyzed to study the mean, maximum and distributions of deviation in order to obtain the corresponding navigation ability. The verification results show that the performance based navigation(PBN) accuracy of the aircraft can meet the requirements of RNP 0.1 in the airworthiness standard, and the quality of the RNP program is up to the standard. [ABSTRACT FROM AUTHOR]

Taking the design data and operation parameter of actual molecular sieve dehydration unit as example, the main technique process, equipment design and adjustment of the operation data are introduced in detail. It gives reference to similar design of molecular sieve dehydration unit and provides ideas for reducing energy consume of molecular sieve dehydration unit. [ABSTRACT FROM AUTHOR]