• Proceedings of the Korea Multimedia Society Conference
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• 2012.05a
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• pp.340-342
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• 2012

Integral Imaging (II) is an attractive technique for three-dimensional (3D) image, video display and recording. Inherently, the high resolution II requires an enormous amount of data for storing and transmitting of 3D scenes. Compression techniques attempt to evade this issue. In this study, we made a comparative performance analysis of popular transforming/compression techniques such as the Discrete Cosine Transform (DCT) and the Discrete Wavelet Transform (DWT) in order to compress 3D-II. The standard baseline JPEG (Joint Photographic Experts Group) using DCT and JPEG 2000 using DWT methods were manipulated in our experiments. In our analysis, we have shown that the DWT based JPEG 2000 compression methodology could be a good alternative for 3D-II.

• Proceedings of the Optical Society of Korea Conference
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• 2009.10a
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• pp.6-7
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• 2009

We proposed the two-dimensional (2D) / three-dimensional (3D) convertible modified integral imaging system using functional polarizing film named $imazer^{TM}$, which transfer or scatter the incident light ray according to the polarizing direction of ray. When the incident light rays transfer to $imazer^{TM}$, the rays generate 3D image through the process of the modified integral imaging system. However, the scattered light rays generate 2D image through the simple backlight scheme when the incident rays are scattered by the film. The proposed method can be implemented the partial 3D display system without any mechanical movements. In this paper, we propose and verify our system using some basic experiments and its results.

• Proceedings of the Korean Information Science Society Conference
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• 2001.04a
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• pp.91-93
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• 2001

볼륨 렌더링(Volume Rendering)은 과학, 의학, 공학 등의 분야에서 3차원 볼륨 데이터(Volume Date)를 효과적으로 시각화(Visualization)하는 목적으로 널리 사용되고 있으며 고화질 영상 요구로 인해 3차원 볼륨 데이터의 크기는 점차 대용량화되어 가는 추세이다. 이러한 대용량 데이터의 고성능 처리를 위해서는 병렬입출력이 필수적이다. 본 논문에서는 병렬볼륨 렌더링에 최적화된 병렬화일시스템 PBS(Parallel Block Server)을 제안한다. PBS는 고성능 입출력 제공을 위해서 데이터입출력에 대한 응용 프로그램의 집적 통제를 위한 다양한 기능을 제공하도록 설계되어 있다. 이러한 직접통제의 단점인 복잡한 인터페이스 문제를 해결하기 위해서 볼륨 렌더링에 최적화된 데이터 입출력 전략을 자동화시킨 PBS 기반 라이브러리 VRPIO(Volume Rendering Parallel Input Output)를 제공한다.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2006.07a
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• pp.461-461
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• 2006

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2006.07a
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• pp.281-281
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• 2006

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.44 no.3 s.357
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• pp.105-110
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• 2007

We have built the millimeter-wave passive imaging system with a lens and mechanical scan antenna. The lens was designed based on optical theory in order to focus millimeter-wane. A full image was taken from image points scanned by Placing antenna at the representative focal plane selectively. An integrated antenna array device for low-loss and low-noise with the array of 4 by 1, where components such as antenna, balun, MMIC, and detector were assembled on a sin91e substrate, and a fermi tapered slot antenna with high-gain and low-side lobe were used for elements of this millimeter-wave passive imaging system. Two dimensional antenna arrangement on focal plane was achieved in this imaging system.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.43 no.12 s.354
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• pp.55-64
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• 2006

This work proposes a calibration-free 14b 70MS/s 0.13um CMOS ADC for high-performance integrated systems such as WLAN and high-definition video systems simultaneously requiring high resolution, low power, and small size at high speed. The proposed ADC employs signal insensitive 3-D fully symmetric layout techniques in two MDACs for high matching accuracy without any calibration. A three-stage pipeline architecture minimizes power consumption and chip area at the target resolution and sampling rate. The input SHA with a controlled trans-conductance ratio of two amplifier stages simultaneously achieves high gain and high phase margin with gate-bootstrapped sampling switches for 14b input accuracy at the Nyquist frequency. A back-end sub-ranging flash ADC with open-loop offset cancellation and interpolation achieves 6b accuracy at 70MS/s. Low-noise current and voltage references are employed on chip with optional off-chip reference voltages. The prototype ADC implemented in a 0.13um CMOS is based on a 0.35um minimum channel length for 2.5V applications. The measured DNL and INL are within 0.65LSB and l.80LSB, respectively. The prototype ADC shows maximum SNDR and SFDR of 66dB and 81dB and a power consumption of 235mW at 70MS/s. The active die area is $3.3mm^2$.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.9
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• pp.4152-4158
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• 2012

The Stereo X-ray inspection system is designed for effectively providing the additional information of objects than the conventional inspection system that offers only 2D cross-section of objects. We studied the geometric improvement of the stereo X-ray inspection system, the stereo matching algorithm of the single object using the edge and the volume reconstruction method for the inspected object. In this paper, we conduct a matching algorithm to find the correspondences between the images and reconstruct 3-D shapes of real objects using the stereo X-ray images. Also, we apply a new 3D reconstruction algorithm for the discrimination of two objects. For the separation of the overlapping objects, we calculate the vector of the object and divide inner and outer voxel of objects. And for the elimination of the overlapping area, we study the reconstruct 3D shapes using the threshold based Z-axis. The experimental results show that the proposed technique can enhance the accuracy of stereo matching and give more efficient visualization for overlap objects in the restricted environment.

• Nuclear Engineering and Technology
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• v.12 no.1
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• pp.19-28
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• 1980

An instant labelling technique for lyophilized pyrophosphate with $^{99m}$Tc is described labelling yield of about 90% is obtained at the pH range 3.5-5.5 on reconstitution with sodium pertechnetate-$^{99m}$ Tc solution. The final product is controlled by a modified two dimensional paper chromatography using 85% methanol and 0.85% saline, and biodynamic investigations are performed on white mice. Generally, the less amount of stannous chloride is used. the higher labelling yield is obtained. The molar ratio of pyrophosphate to stannous chloride of 10 : 1 ~ 50 : 1 is sufficient. The more amount of reduced unbound $^{99m}$Tc is injected, the more radioactivity is incorporated in the liver. Thus. the cause of the false bone-imaging is attributable to the presence of reduced unbound $^{99m}$Tc which is known to be well adsorbed to oxidized tin colloidals. The maximum uptake ratio of bone: liver in mice, in weight basis, 35 : 1 is achieved in lime of 60 min. or so. Tile preparation is suitable for clinical investigations on patients with bone diseases.iseases.

• Korean Journal of Optics and Photonics
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• v.24 no.1
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• pp.1-8
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• 2013

In this paper, we report design, fabrication and characterization of the WBRM (Wide Band Receiver Module) for LADAR (LAser Detection And Ranging) application. The WBRM has been designed and fabricated using self-made APD (Avalanche Photodiode) and TIA (Trans-impedance Amplifier). The APD and TIA chips have been integrated on 12-pin TO8 header using self-made ceramic submount and circuit. The WBRM module showed 450 ps of rise time, and corresponding 780 MHz bandwidth. Furthermore, it showed very low output noise less than 0.8 mV, and higher SNR than 15 for 150 nW of MDS(Minimum Detectable Signal). To the author's knowledge, this is the best performance of an optical receiver module for LIDAR fabricated by 200 um InGaAs APD.