Abstract: The aim of the present invention is to achieve a low delay and high bandwidth efficiency in an upstream bandwidth and to accurately reflect assured bandwidth in an actual transmitted bandwidth. To achieve this, in the present invention the maximum value and the transmission cycle of a requested bandwidth are set for each service class. The present invention allocates bandwidth to a service path terminating section based on excess allocated bandwidth and requested bandwidth of each service path terminating section. For each service path terminating section the present invention also selects one bandwidth out of a plurality of bandwidths requested by a service path terminating section in such a manner that the sum value of the allocated bandwidths of the plurality of service path terminating sections is within a predetermined range.

Abstract: In a P2MP system in which upstream bandwidth is shared by a plurality of ONUs, a dynamic bandwidth allocation circuit is provided which reduces the consumption of memory capacity, and avoids the divergence of parameters. A dynamic bandwidth allocation circuit provided in an optical line terminal (OLT) calculates, for each cycle and for each ONU, a target data size (targetj,k) which constitutes a target for allocated data size (allocatedj,k). Furthermore, taking the time constant of an exponential weighted moving average as ?, and taking ?=(??1)/(?+1), an ideal allocated data size (idealj,k) is calculated by idealj,k=targetj,k?(?/(1??))·excessj,k?1. Furthermore, an excess allocated data size (excessj,k) per one cycle is calculated by excessj,k=?·excessj,k?1+(1??)·(allocatedj,k?targetj,k). If idealj,k<0, the condition that bandwidth allocation is not granted is used for bandwidth allocation.

Abstract: In a P2MP system in which upstream bandwidth is shared by a plurality of ONUs, a dynamic bandwidth allocation circuit is provided which reduces the consumption of memory capacity, and avoids the divergence of parameters. A dynamic bandwidth allocation circuit provided in an optical line terminal (OLT) calculates, for each cycle and for each ONU, a target data size (targetj,k) which constitutes a target for allocated data size (allocatedj,k). Furthermore, taking the time constant of an exponential weighted moving average as ?, and taking ?=(??1)/(?+1), an ideal allocated data size (idealj,k) is calculated by idealj,k=targetj,k?(?/(1??))·excessj,k?1. Furthermore, an excess allocated data size (excessj,k) per one cycle is calculated by excessj,k=?·excessj,k?1+(1??)·(allocatedj,k?targetj,k). If idealj,k<0, the condition that bandwidth allocation is not granted is used for bandwidth allocation.

Abstract: A roll changing apparatus for a four-high rolling mill comprises rails, provided in a rolling mill stand and on a work side of the rolling mill, for incoming and outgoing of a work roll assembly and a backup roll assembly, and a pusher, provided on a drive side or the work side of the rolling mill, for roll admission and withdrawal for both of work rolls and backup rolls. The roll changing apparatus can be modified into a side shift type roll changing apparatus with ease, at a low cost, and in a short time.

Abstract: The aim of the present invention is to achieve a low delay and high bandwidth efficiency in an upstream bandwidth and to accurately reflect assured bandwidth in an actual transmitted bandwidth. To achieve this, in the present invention the maximum value and the transmission cycle of a requested bandwidth are set for each service class. The present invention allocates bandwidth to a service path terminating section based on excess allocated bandwidth and requested bandwidth of each service path terminating section. For each service path terminating section the present invention also selects one bandwidth out of a plurality of bandwidths requested by a service path terminating section in such a manner that the sum value of the allocated bandwidths of the plurality of service path terminating sections is within a predetermined range.

Abstract: Hydraulic cylinders are provided in a housing so as to be opposed to roll chocks. Each of the hydraulic cylinders is constituted by movably fitting a thin plunger via a liner into a cylinder fixed to the housing, movably fitting a concave portion of the thin plunger over a center guide on the cylinder to form guide means, and connecting a liner for thrusting each of the roll chocks to a front end portion of the thin plunger.

Abstract: A roll changing apparatus for a four-high rolling mill comprises rails, provided in a rolling mill stand and on a work side of the rolling mill, for incoming and outgoing of a work roll assembly and a backup roll assembly, and a pusher, provided on a drive side or the work side of the rolling mill, for roll admission and withdrawal for both of work rolls and backup rolls. The roll changing apparatus can be modified into a side shift type roll changing apparatus with ease, at a low cost, and in a short time.