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.

Videotelephone apparatus for transmitting high and low resolution video signals over telephone exchange lines

Abstract: In an audiovisual communication, a first high fram rate video signal is derived from a motion image and converted to a low fram rate low resolution multiframe signal. A second high frame rate video signal is derived from an still image and converted to a single frame high resolution signal. Because of the low frame rates, the frequencies of the low and high resolution signals are within the range of frequencies of a telephone exchange line. A switching matrix is provided to sequentially couple both the low and high resolution signals to a transmission line in response to a mode select signal. The single frame high resolution signal is stored into a memory at the receiving end and repeatedly retrieved out of the memory into a display through the switching matrix.

Flip chip type semiconductor device and method for manufacturing the same

Abstract: A multilayer wiring structure is formed on a flat metal plate and then an entire surface of the metal plate is etched away to thereby leave only a multilayer wiring layer. An insulating substrate having through hole sections is bonded to the multilayer wiring layer, a conductive bonding agent is embedded into the through hole section, a semiconductor chip is mounted and a solder ball is coupled.

Decay property of regularity-loss type for dissipative timoshenko system

Abstract: We study the decay property of the dissipative Timoshenko system in the one-dimensional whole space. We derive the L2 decay estimates of solutions in a general situation and observe that this decay structure is of the regularity-loss type. Also, we give a refinement of these decay estimates for some special initial data. Moreover, under enough regularity assumption on the initial data, we show that the solution approaches the linear diffusion wave expressed in terms of the heat kernels as time tends to infinity. The proof is based on the detailed pointwise estimates of solutions in the Fourier space.

Card type recording medium, certifying method and apparatus for the recording medium, forming system for recording medium, enciphering system, decoder therefor, and recording medium

Abstract: In a card type recording medium containing a data area where data containing ID information of a holder are recorded, and an image area where image data are recorded, in the image area are recorded second image data which are generated by transforming first image data specifying the holder to frequency-area data, adding the transformed frequency-area data with the ID information and inversely transforming the added data to image signals.