Shinji Fukuma

A Novel Detection Method of Active and Reactive Currents in Single-Phase Circuits Using the Correlation and Cross-Correlation Coefficients and Its Applications

This paper proposes a novel method of detecting the active and reactive currents in single-phase circuits using the correlation and cross-correlation coefficients in the time domain. The active current is detected using the correlation coefficient between the source voltage and load current waveforms, and the reactive current is detected using the cross-correlation coefficient. The basic principle of the proposed detection method is discussed, and the proposed method is applied to a previously proposed single-phase shunt active filter for consumer electronic equipment. Simulation and experimental results demonstrate the excellent practicability of the proposed detection method.

Lossless coding of still images with four channel prediction

In this paper a new lossless coding of digital image data with a four channel filter bank (4ch FB) having optimized filter coefficients is proposed. The method has an advantage of less restrictions on optimizing the filter coefficients compared to the cascade form of two channel filter banks (2ch FB). Simulation results are shown to confirm its effectiveness.

Switching Wavelet Transform for ROI Image Coding

In region-of-interest (ROI) image coding based on wavelet transforms, the tap length of the wavelet filter as well as energy compaction characteristics affect the quality of the restored image. This paper presents a wavelet transform comprised of two wavelet filter sets with different tap lengths. The wavelet filter is switched to the shorter-length set to code a ROI of an image and to the longer-length one for the remaining region, the region of non-interest (RONI). ROI coding examples demonstrate that this switching wavelet transform provides better quality levels than fixed transforms under the same total bits; the quality of the recovered ROI is improved in the lossy coding of both regions while that of the full image is improved in the lossless coding of the ROI.

Lossless color coordinate transform for lossless color image coding

This paper proposes a lossless color coordinate transform for lossless color image coding. Lossless color coordinate transforms are used to remove the correlation and to bias the signal energy ratio between the color signal components. In order to form the lossless coding, a ladder network is used. It is confirmed by the numerical simulations that the performance of the lossless coding scheme with the lossless color coordinate transform is better than that without the lossless color coordinate transform.

Two channel non-separable 2D subband coding and its optimization

A new lossy/lossless coding of digital image data with two channel non-separable filter bank is proposed. The method has freedom of selecting taps and coefficients of the filters and this freedom is used for maximizing the coding gain. Simulation results are shown to confirm its effectiveness.

Physical motion analysis system in driving using image processing

This paper proposes an optical motion capture system for physical motion analysis in driving. Markers for motion capture consist of two high intensity LEDs, one for position measurement and the other for pilot signal. The pilot marker flashes synchronized with the periodic pulse, which is generated by multiplying the UTC second (1PPS) obtained by the GPS. Video cameras are also triggered with the pulse and thus the proposed system can distinguish the marker every one second in the automobile in the daytime. This copes with problems in optical motion capture system, occlusions and swappings.

Inter color and inter/intra band prediction on reversible wavelet for lossless progressive color coding

We propose a new lossless progressive color coding of color still images. An image is firstly transformed by reversible wavelet transform such as S transform due to progressive transmission of image. And we utilize for an improvement of the compression performance not only for the inter color correlation but also the inter/intra band correlation of the subbands of reversible wavelet transform. We show three effective predictors to remove that correlation, and it is confirmed by numerical experiment that combination of all the predictions is the best in performance.

A real-time GPU-based coupled fluid-structure simulation with haptic interaction

Time series scientific simulation on supercomputers generates huge amounts of data at each time step. In the big data era, these data become impossible to be stored anymore, so simultaneous analysis of these data is strongly demanded. In order to realize such an on-the-fly intuitive analysis of simulation, this paper showcases a multimodal visualization and steering system with visual and haptic interfaces for a real-time GPU-based coupled fluid-structure simulation. Since the nature of touching sense of human beings requires extremely fast and continuous refreshing to form authentic feeling, parallel techniques were utilized to speed up haptic updating to around one millisecond. A middle-layer interface for a haptic device was developed to realize the ease of use of this device. Furthermore, a model of palpation was proposed to allow users to touch, push and sense the dynamic fluid motion inside a deformable tube.

A Simple and Real-Time Parallel Compression of Time Series Scientific Simulation Data for Interactive and Cooperative Supercomputing

In order to realize a cooperative supercomputing environment, Large-scale scientific simulation data should be exchanged among supercomputers over the Internet. To maintain the interactivity of the time-series simulation in such an environment, real-time data compression is required. Given the accuracy requirements of scientific simulation, we only focus on lossless data compression. In this paper, we propose Think Mantissa as Integer method to decrease the entropy of scientific datasets, achieving a good compression ratio and speeds. We evaluate this scheme in two experiments and compare it with the existing compression strategies (gzip, bzip2). Our approach gets about a 30% improvement in the compression ratio and hundreds of times speed acceleration. We also computed the total time of the data transfer using this method under some specific bandwidth cases, and nearly all of them have gotten a good acceleration.

Prototype Implementation of a GPU-based Interactive Coupled Fluid-Structure Simulation

This paper reports a prototype implementation of 3D Fluid-Structure Simulation. In this implementation, heartbeat fluid flows inside a rectangular tube where the operator can interactively change the width of the tube. In order to achieve interactive simulation speed, some parts of the simulation is accelerated by GPU. For further improvement of the simulation speed, two techniques have been examined: the first one reduces the communication between CPU and GPU, and the second one offloads a whole fluid flow simulation onto GPU.