The Secondary flow in a curved duct of square cross-section, is investigated numerically using the spectral method. The walls of the duct except the outer wall rotate around the centre of curvature and an azimuthal pressure gradient is imposed. Multiple solutions are obtained at the same flow condition. It is also found that the secondary flow in a cross-section consists of two-vortex, four-vortex, eight-vortex or even non-symmetric vortex with respect to the centre line of the cross-section. The linear stability analysis for the multiple solution is also carried out to investigate the actual flow patterns.

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Aiming at the difference of the people as a particularity resource。In this paper ,the personnel training mode is divided into junior and senior, and a multi-objective integer programming model is established at the lowest cost of staff training, the highest man-machine adaptability degree and minimum personnel workload. Calculating example of a real production cell is presented. The results show that the model is correct and the necessity for classification of training modes.The model can help the management to adopt reasonable training mode and achieve desirable objectives.

Although Application-level multicast is a new multi-point data transmission model, there is no mature and effective scheme for network heterogeneity problem. This paper proposes an agent-based adaptive media multicast system, i.e., the so-called iPALM system (Proxy based Application-level Multicast). It uses efficiently data transmission of IP multicast in LAN, and every IP multicast area sets one agent server named MPN, the backbone network composed of MPNs transmits data using application-level multicast. At the same time, iPALM provides the head format of system protocol, and the definition of transmission message in XML format which demonstrates that iPALM system can satisfy every different application requirement, and improves the media service quality in heterogeneous environment.