NEC

About: NEC is a company organization based out in Tokyo, Japan. It is known for research contribution in the topics: Signal & Layer (electronics). The organization has 33269 authors who have published 57670 publications receiving 835952 citations. The organization is also known as: NEC Corporation & NEC Electronics Corporation.

Ring network with temporary master node for collecting data from slave nodes during failure

Abstract: In a ring network where network nodes are interconnected by an optical fiber ring, one of the nodes acts as a master node and each of the other nodes acts as a slave node. The master node successively designates a different slave node in a descending order of priorities, transmits a command message to the designated slave node, and updates its memory with a response message from the designated node. If the command message is received, each designated slave node updates its memory with data contained in the command message and returns a response message to the master node. If the command message is not received, each slave node, acting as a temporary master node, designates a different one of the other slave nodes in descending order, transmits a command message to each designated node, and updates its memory with a response message therefrom. Each temporary master node repeats the process until it receives a command message from another temporary master node having a priority higher than the priority of the sending node.

Lead frame for use in a semiconductor device and method of manufacturing the semiconductor device using the same

Abstract: A distance between each two sides adjacent to a first portion X of the outer peripheral portion of an island portion 3 and the inner end of an inner lead portion 4 is set to d 1 while the distance between each two sides adjacent to a second portion Y, which is diagonal to the first portion X, and the inner end of the inner lead portion 4 is set to d 2 (

Mobile terminal management system, network device, and mobile terminal operation control method used for them

Abstract: The object of the present invention is to provide a mobile terminal management system in which a mobile terminal can rapidly decide a PMIP operation or CMIP operation in accordance with the policy of a network administrator. According to the present invention, a network notifies a mobile terminal whether or not the mobile terminal is operable with the PMIP function. Moreover, the mobile terminal of the present invention transmits, to the network, notification saying that a use request for CMIP function has been stored in accordance with the policy of a terminal side, such as user setting or service contents, upon connection or hand-over to the access network.

Ultra fast quantum key distribution over a 97 km installed telecom fiber with wavelength division multiplexing clock synchronization

Abstract: We demonstrated ultra fast BB84 quantum key distribution (QKD) transmission at 625 MHz clock rate through a 97 km field-installed fiber using practical clock synchronization based on wavelength-division multiplexing (WDM). We succeeded in over-one-hour stable key generation at a high sifted key rate of 2.4 kbps and a low quantum bit error rate (QBER) of 2.9%. The asymptotic secure key rate was estimated to be 0.78–0.82 kbps from the transmission data with the decoy method of average photon numbers 0, 0.15, and 0.4 photons/pulse.