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We present a digital holography using high dynamic range (HDR) imaging to improve quality of the reconstructed image of digital holography. The technique extends the dynamic range of the digitally recorded hologram using multiple holograms recorded with different exposures. We numerically and experimentally demonstrated the technique based on an off-axis digital holography system. In the numerical simulation and experiment, the quality of the reconstructed images by the proposed technique is higher than that by the conventional digital holography without HDR imaging.

This paper presents a new smart grid infrastructure for active distribution systems that will allow continuous and accurate monitoring of distribution system operations and customer utilization of electric power. The infrastructure allows a complete array of applications. The paper discusses four specific applications: a) protection against downed conductors; b) load levelization; c) loss minimization; and d) reliability enhancement.

An efficient mobile video streaming system needs to cope with unstable network bandwidth and limited battery life. We propose a novel streaming system which jointly considers picture quality, bit-rate and energy consumption. Reducing the spatial resolution of a video stream adaptively proves to be more efficient in terms of picture quality and energy consumption than conventional rate control using only adjustment of quantization parameter. We apply the same scheme to scalable coding for large-scale mobile video streaming. This extends the adaptation of an SVC stream to lower bit-rates, while maintaining temporal stability. Our approach has been shown to improve picture quality by approximately 0.5 dB in low bit-rate conditions, and also reduces energy consumption by more than 50% compared to conventional video streaming.

Tilt error can affect a serious effect to holographic data storage system using angle(polytopic) multiplexing. Because the tolerance about tilt error is very tight it is important to measure the tilt error and compensate it. In this paper, tilt error measurement system with additional red laser and reflection geometry is suggested and servo control experiments are conducted. A servo controller to compensate tilt error is designed using disturbance observer. Amount of tilt is decreased smaller than 0.01 degree and signal-to-noise ratio is increased with the tilt servo controller when 0.216 degree of tilt disturbance is applied.

In this paper, we aim to reduce the channel switching time for Internet protocol TV (IPTV) without unduly influencing the picture quality. For this purpose, we propose to adopt the H.264 scalable video coding scheme, for which we allocate a base layer and enhancement layers of each channel to two separate multicast groups. In preview mode, users access the base layers of different channels already stored in a buffer, so they can switch between channels without delay. In watching mode, they use both the base and enhancement layers of the selected channel to achieve full quality. While providing fast channel switching in the preview mode, our approach proves to maintain the picture quality similar to the case of single layer coding. An experimental result, for example, shows that, even with complicated scenes, a 1.5 Mbps scalable video stream for IPTV has achieved a good picture quality with a PSNR of 33.7 dB1.

Comprehensive study on control system design for a rapid thermal processing (RTP) equipment has been conducted with the purpose to obtain maximum temperature uniformity across the wafer surface, while precisely tracking a given reference trajectory. The study covers from model development, identification, optimum multivariable iterative learning control (ILC), to reduced-order controller design. The highlight of the study is the ILC technique on the basis of a semi-empirical dynamic radiation model named as T/sup 4/-model. It was shown that the T/sup 4/-model-based ILC technique can remarkably improve the performance of RTP control compared with the ordinary linear model-based ILC. In addition, reduced-order control methods and the associated optimum sensor location have been addressed. The proposed techniques have been evaluated in an RTP equipment fabricating 8-in wafers.

In the above titled paper (ibid., vol. 55, no. 3, pp. 1682-1689, Aug. 09), Figures 3 and 11 were inadvertently omitted in production. The figures are presented here.