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Displaying 1-16 of 16 articles from this issue
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Article type: Cover
Pages Cover1-
Published: December 17, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSDownload PDF (13K) -
Article type: Index
Pages Toc1-
Published: December 17, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSDownload PDF (59K) -
Kazuhiro KAWAHARAYAMA, Tokuhiro KITAMIArticle type: Article
Session ID: BCS99-81
Published: December 17, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSIn the previous works, the cell loss process in ATM switches was approximately modeled by a Gilbert Model with 2 states taking account only of cell loss runs. This paper presents more accurate cell loss process models based on the simulated cell discard process due to buffer overflow in an input-buffered ATM switch. The proposed cell discard process models are an IPP Model and a Fritchman Model with 3 states. These models are introduced taking account of the aggregated performance of cell loss runs and cell loss free runs. The simulation results shows that the proposed models are useful.View full abstractDownload PDF (506K) -
Shuji Nishijima, Kohei OtakeArticle type: Article
Session ID: BCS99-82
Published: December 17, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSIn this paper, we propose a new technique that can compensate frequency offset which causes the intercarrier interference(ICI)in OFDM systems. This proposed technique is a nondata-aided type which means the frequency offset compensation can be done using only the information bearing symbols, and it uses an adaptive filter to estimate frequency offset. Since the tracking range by this technique is influenced by the channel characteristics, the number of subcarriers and the number of guard-subcarriers, we analyse these characteristics theoretically and clarify compensation performances by computer simulation.View full abstractDownload PDF (637K) -
Hiroshi MIURA, Kohei OTAKEArticle type: Article
Session ID: BCS99-83
Published: December 17, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSThe multicarrier CDMA(MC-CDMA)communication system based on a combination of CDMA and OFDM techniques, has gained much attention as one of the most promissing next generation mobile communication system which is required of high data rate transmission. In this paper, we propose a quasi-synchronous MC-CDMA scheme with quard time inserted signal format, which can easily suppress both inter symbol and inter channel interfaces and this achieves good BER performances. It could be applicable even to the uplink due to the quasi-synchronous network operation which only requires the synchronization accuracy within guard time interval. The system model description and the system analisis under the multipath fading environment are made and the BER equations are derived for equal gain combining(EGC)and maximum ratio combining(MRC)receivers. Adaptive detectors for both receivers are also descrived. The computer simulation is conducted to clarify the BER characteristics of EGC and MRC receivers of them.View full abstractDownload PDF (668K) -
Shoji Shiomoto, Tetsuo SumidaArticle type: Article
Session ID: BCS99-84
Published: December 17, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSIn a bit stream multiplexing model used for the future digital broadcasting systems, establishment of the integration method which can deal with various contents and perform under the severe condition for transmission band width is desired. This paper introduces concept of a new parameter for delay estimation of data in multiplexing model. We also propose a new type of algorithm for multiplex operation to keep the bit stream in synchronization, which is robust even in momentary traffic congestion, and verify its performance through the simulation of bit stream multiplexing.View full abstractDownload PDF (687K) -
[in Japanese]Article type: Article
Session ID: BCS99-85
Published: December 17, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESS -
Satoshi Takase, Takeshi Ogihara, Yukio KanedaArticle type: Article
Session ID: BCS99-86
Published: December 17, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSUsual compression methods for limited color images do not use effectively two-dimensional context of images. In this paper, we propose a variation of finite context model to improve compression ratio. In this method, a context is made from the neighborhood of the current pixel to refer to two-dimensional information. We also propose a technique to reduce execution time using simply structured model. Instead of color indexes, a context is constructed from labels which represent the location of pixels with the same color in the neighborhood. We will also show the results of compression experiments.View full abstractDownload PDF (751K) -
Yutaka KANEKO, Yoshiaki SHISHIKUI, Yasuaki KANATSUGU, Yutaka TANAKAArticle type: Article
Session ID: BCS99-87
Published: December 17, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSThis paper describes a motion estimation method with eigenvalue algorithm matching local image feature. The proposed method first formulates the optical flow using the block gradient method with eigenvalue algorithm, and then low reliability optical flow is classified according to the characteristics inside the block. We introduce two estimation methods based on eigenvalue algorithm for improvement in accuracy. The first method is based on robust estimation. We apply this method to the blocks which include multiple movements. The second method is applied to the blocks in which one typical gradient alone exists. In the method, we complement the eigenvector from the object with the same edge in the subjective block, and then motion estimation is carried out with the complementary eigenvector. Experimental results show that the proposed method improves the estimation accuracy.View full abstractDownload PDF (1009K) -
Yoshiyuki ITO, Toshiaki FUJII, Tadahiko KIMOTO, Masayuki TANIMOTOArticle type: Article
Session ID: BCS99-88
Published: December 17, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSDiscrete consine transform(DCT)is widely used as a method of image coding. In the image coding scheme using DCT like JPEG, the DC coefficient is predicted by using the correlation of neighboring blocks. Further, the prediction is done on the AC coefficient in MPEG4. However, the prediction of the AC coefficient is difficult because the correlation of it is low, and the efficiency may reversely lower by the prediction. By using all blocks in the image, it may be able to do the prediction which is better than the conventional method. In this paper, we propose and examine new prediction system of the AC coefficient using all blocks.View full abstractDownload PDF (527K) -
Kumi Jinzenji, Hiroshi Watanabe, Naoki KobayashiArticle type: Article
Session ID: BCS99-89
Published: December 17, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSThe new video coding standard MPEG-4 provides content-based functionality and low bit-rate video compression. We focused on the "sprite coding" supported MPEG-4 Version 1 Main profile in order to achieve "VHS quality video on 2B(128kbps)" for narrow-band transmission such as the Internet. Automatic VOP(Video Object Plane)generation technologies are being studied as one of the most important issues of MPEG-4 object coding. This paper proposes a two-layer VOP generation scheme with some core algorithms such as GME(Global Motion Estimation), foreground moving object extraction, and background sprite generation. This paper also describes a shape information reduction method for foreground objects. Using this method, shape information is compressed by 90%. Experiments are conducted on VOP generation and video coding with MPEG-4. Coding efficiency is several times higher than that of typical existing video coding schemes at the same objective image quality.View full abstractDownload PDF (1215K) -
Mei KODAMA, Masayuki TAKEMOTO, Tomoji IKEDA, Tsuyoshi MASAKIArticle type: Article
Session ID: BCS99-90
Published: December 17, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSWe had indicated communication services using multimedia scalability packages(MSP), which can provide multimedia information accoding to functionality and availability for users. In this paper, we propose the MSP video searching system as one of the MSP multimedia services. And then, we inspected effects of methods, which have image feature sampling as first step and metching process as second step in video searching system. Especially, we study on effective video searching methods by two dispersion process from the client side and the server side using the MSP in reference tables.View full abstractDownload PDF (634K) -
Mei KODAMA, Tomoji IKEDA, Masayuki TAKEMOTO, Tsuyoshi MASAKIArticle type: Article
Session ID: BCS99-91
Published: December 17, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSWe had indicated communication services using multimedia scalability packages(MSP), which can provide multimedia information accoding to functionality and availability for users. In this paper, we propose the MSP video searching system as one of the MSP multimedia services. And then, the structuring methods of the data architecture are condisered to realize it. Especially, we study on the description schemes in mode data, action procedure, the generating data procesure in searching process. It needs automatic information descripter in both of client and server terminal. That's because users retrieve searching results using exchanging MSP data through network.View full abstractDownload PDF (604K) -
Mei KODAMA, Tomoji IKEDAArticle type: Article
Session ID: BCS99-92
Published: December 17, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSWe had indicated communication services using multimedia scalability packages(MSP), which can provide multimedia information accoding to functionality and availability for users. In this paper, we propose the MSP video searching system as one of the MSP multimedia services. And then, the structuring methods of the data architecture are condisered to realize it. Especially, we study on the description schemes in mode data, action procedure, the generating data procedure in searching process. It needs to update the mode data could control the remote play and MSP data access. That's because we have to make good use of the information in exchanging MSP data through network.View full abstractDownload PDF (602K) -
Mei KODAMA, Hidekazu TAKAHASHI, Masayuki TAKEMOTO, Tomoji IKEDA, Tsuyo ...Article type: Article
Session ID: BCS99-93
Published: December 17, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSIn this paper, we pay attention to video matching methods as image serching system. Especially, frecuencys of luminance signals are used. In this paper, we proposed the video matching methods using temporal variances as image characteristics. And then, we verified these schemes on the matching process and matching pattern. The proposed methods were efficient by simulation results. From the viewpoint of matching process, the grouping method was available in our mothods.View full abstractDownload PDF (574K) -
Article type: Appendix
Pages App1-
Published: December 17, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSDownload PDF (81K)
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