Today's Internet only provides '%est-effort" service. Traffic is processed as quickly as possible, but with no commitment as to bandwidth or latency guarantee. This is inadequate for applications requiring timeliness such as video conference, video+ndemand (VOD) and voice over IP (VoIP), etc. For these applications to be widely used, Quality of Service (QoS) must be quantified and managed efficiently by the Internet. This paper focuses on QoS provisioning using IPv6 flow label field. In this paper, we first investigate the flow label specification and its usage in QoS support proposed in the literature, then propose an end-to-end QoS scheme using the IPv6 flow label field, which employs a hybrid approach for flow label specification and a " flow label option" for IPv4 packet. This proposed QoS scheme is especially designed for transitional IP network containing both IPv4 and IPv6 network nodes, which is the reality in the process of Internet transition from IPv4 to IPv6. Our simulation results show that the proposed QoS scheme can efficiently differentiate various types of traffic to meet differentiated QoS requirements in a transitional network containing IPv4 and IPv6 routers.

In Gara-bo spinning, relations among spinning conditions and structural parameters of yarn are very complicated and have not been formulated. when the spinning is in a steady state, some formulae were derived about a relation among the yarn thickness D, the twist rate A, the established yarn tension T and the fiber density pp. Namely, where, CuA, Cm and CdA are coefficients without relation to T and pp.Moreover, based upon the essential principle of Gara-bo, a device was developed for the precise measurement by using electronic technology. Through some experiments done with the device, it is ascertained that Cu, Cm and CdA can be almost considered as a constant and the theoretical formulae can be used with sufficient suitability.Therefore, when the yarn thickness deviated from the hoped value in spinning process, the compensation quantity of the established tension, which modifies the deviation, can be decided by the formulae.

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