Abstract: A cell handover method and apparatus, and user equipment are provided. The method includes: when User Equipment (UE) camps on a first cell, obtaining first information, where the first information is used to indicate an abnormal situation when the UE uses a data network corresponding to the first cell; and when the first information meets a first preset condition, handing over from the first cell to a second cell, where the second cell is a cell whose signal quality parameter meets a second preset condition, or the second cell is a cell with the highest access priority; where the first information includes at least one of the following: information about a target data packet, network-related information corresponding to at least one application, a target uplink resource, a data accumulation amount at a data link layer, and a channel quality parameter of the first cell.

Abstract: Bismuth (Bi) doped optical fibers (BiDF) and Bi-doped fiber amplifiers (BiDFA) are shown and described. The BiDF comprises a gain band and an auxiliary band. The gain band has a first center wavelength (?1) and a first six decibel (6 dB) gain bandwidth. The auxiliary band has a second center wavelength (?2), with ?2>?1. The system further comprises a signal source and a pump source that are optically coupled to the BiDF. The signal source provides an optical signal at ?1, while the pump source provides pump light at a pump wavelength (?3).

Abstract: A file retrieval method of a file allocation table (FAT) system is provided, which includes steps of: A: acquiring cluster numbers of all clusters of a file; B: sorting the cluster numbers to create a cluster number index table; and C: looking up the cluster number index table to obtain a cluster number of a file cluster to be retrieved, and acquiring a content of the file cluster to be retrieved from a physical storage address corresponding to the cluster number. A file retrieval device is further provided, which includes a central processing unit (CPU) and an address index storage unit. The address index storage unit stores a cluster number index table of sorted cluster numbers of all clusters of a file. The CPU is adapted to obtain a cluster number of a file cluster to be retrieved according to the cluster number index table during retrieving and acquire a content of the file cluster to be retrieved from a physical storage address corresponding to the cluster number.