• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 제14회 신호처리 합동 학술대회 논문집
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• pp.47-50
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• 2001

본 논문에서는 프레임 메모리를 줄이는 간이형 비디오 디코더의 다섯가지 알고리즘을 연구하여 성능을 비교한다. fixed-length ADPCM 기법을 적용하여 메모리를 줄이는 알고리즘과 수평 방향으로 decimation 하는 방법, 그리고 DCT 계수를 filtering 하는 방법을 구현하고 이보다 더 압축률을 높여서 수평 방향으로 decimation 하거나 DCT 계수를 filtering 하는 방법에 ADPCM 기법을 결합한다. 이렇게 함으로써 원래의 비디오 디코더 프레임 메모리의 25% 까지 메모리를 줄일 수가 있다. 메모리 크기를 줄이는 이점 이외에, 하나의 비디오 디코더 구조가 몇가지 압축 모드를 구성하므로 원하는 복잡도와 메모리 크기에 따라 응용이 자유롭다.

• Journal of Chest Surgery
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• 제27권9호
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• pp.808-811
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• 1994

We reported a successful right pneumonectomy using video assisted thoracoscopy for endobronchial tuberculosis. Thoracoscopic surgery has many advantages in spite of its technical difficulties. These advantages include good cosmetic effects, short hospital stay, decreased postoperative morbidity, and good postoperative pulmonary function.The patient was young unmarried female, and her right lung was nearly total obstructed by endobronchial tuberculous dissemination and secondary pulmonary infection. The procedure was a little complicated by inadequate placements of the thoracoscopic ports and 5cm length utility thoracotomy incision. Minimal pain killer was needed only two days after operation and scar of operative wound was very satisfying. Postoperative course was unusual and the patient was discharged 7 days after operation.

• 한국통신학회:학술대회논문집
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• 한국통신학회 1987년도 춘계학술발표회 논문집
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• pp.31-34
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• 1987

A new efficientcoding system which can transmit video conferenceof viedeophone signals at a 64kbps is proposed. In addition to the interframe and CRC (Conditional Repleni shment Coding) system, BTVQ (Binary Tree searched Vector Quantizer)and RLC (Run Length Coding) methods are incorporated. Couble buffer memory is used for simple comtrol of channel symbol transmission and memory underflow And also buffer memory onerfolw is easily controlled by the thresholds of a MAD (Moving Area Betector)

• 대한인간공학회지
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• 제8권2호
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• pp.35-41
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• 1989

In this paper a new method is proposed to create 3-dimensional coordinate values from two 2- dimensional images (side and front image of objects) using image processing system and two video cameras. This method is task requiring measurements of camera lense distortion, calibrations and conversin 2-dimensional images into 3-dimensional images. This system provides 3-dimensional me- asurement error of +5mm for about 2m length objects.

• ETRI Journal
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• 제30권1호
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• pp.167-169
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• 2008

In this paper, we propose hardware architecture for a high-speed context-adaptive variable length coding (CAVLC) decoder in H.264. In the CAVLC decoder, the codeword length of the current decoding block is used to determine the next input bitstreams (valid bits). Since the computation of valid bits increases the total processing time of CAVLC, we propose two techniques to reduce processing time: one is to reduce the number of decoding steps by introducing a lookup table, and the other is to reduce cycles for calculating the valid bits. The proposed CAVLC decoder can decode $1920{\times}1088$ 30 fps video in real time at a 30.8 MHz clock.

• Nuclear Engineering and Technology
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• 제28권4호
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• pp.379-389
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• 1996

To experimentally investigate the several wave patterns for the horizontal countercurrent stratified air-water flow, a series of systematic experimental studies have been performed. The experiments are carried out in a horizontal pipe with 4m in length and 102mm in inner diameter. The oater and air superficial velocities vary from 0.0004 to 0.0204 and from 0 to 6m/s, respectively. The instantaneous water thickness is measured by parallel-wire conductance probes, and the wave field is recorded by high speed video camera. Also, to evaluate the wave effect on interfacial friction factor, the pressure drop is measured. Statistical data anal)sis is accomplished in order to obtain the fundamental wave parameters such as un amplitude, length and velocity, and spatial growth factor. By using these statistical parameters, the wave regime boundaries can be verified.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 추계종합학술대회 논문집
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• pp.360-363
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• 1999

Video data compression is a major key technology in the field of multimedia applications. Variable-length coding is the most popular data compression technique which has been used in many data compression standards, such as JPEG, MPEG and image data compression standards, etc. In this paper, we present memory efficient VLC decoder architecture for MPEG-2 application which can achieve small memory space and higher throughput. To reduce the memory size, we propose a new grouping, remainder generation method and merged lookup table (LUT) for variable length decoders (VLD's). In the MPEG-2, the discrete cosine transform (DCT) coefficient table zero and one are mapped onto one memory whose space requirement has been minimized by using efficient memory mapping strategy The proposed memory size is only 256 words in spite of mapping two DCT coefficient tables.

• 전자공학회논문지A
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• 제33A권11호
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• pp.152-161
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• 1996

This paper descrisbes the implementation of a 20D DCT that can be used for video conference, JPEG, and MPEG-related applications. The implemented DCT consists of two 1-D DCTs and a transposed memory between them, and uses ROM-based multipliers instead of conventional ones. As the system bit length, the minimum bit length that satisfies the accuracy specified by the ITU standard H.261 was chosen through the simulations using the C language. The proposed design uses a dual port RAM for the transposed memory, and processes two bits of input-pixel data simultaneously t ospeed up addition process using two sets of ROMs. The basic system architecture was designed using th Synopsys schematic editor, and internal modules were described in VHDL and synthesized to logic level after simulation. Then, the compass silicon compiler was used to create the final lyout with 0.8um CMOS libraries, using the standard cell approach. The final layout contains about 110, 000 transistors and has a die area of 4.68mm * 4.96mm, and the system has the processing speed of about 50M pixels/sec.

• 대한교통학회지
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• 제17권2호
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• pp.179-191
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• 1999

고속도로의 교통혼잡을 관리하기 위해서는 근본적으로 혼잡지점 상류부의 진입교통량을 제어해야 한다. 이를 위한 효과적인 램프미터링 운영전략이나 고속도로 교통정보제공방안을 수립하기 위해서는 흔잡영향권(대기행렬 길이)에 관한 신뢰성 있는 데이터가 반드시 필요하다. 고속도로의 대기행렬길이를 산정하기 위해 일반적으로 충격파이론과 대기행렬이론을 제시하고 있으나, 이들은 실질적인 목적으로 사용하는데 현실적으로 여러 가지 한계점을 지니 고 있다. 본 논문은 고속도로상의 병목현상으로 인해 발생하는 대기행렬길이와 혼잡구간의 혼잡정도를 산정할 수 있는 모형개발을 위한 기초연구로서 혼잡상태의 연속류 특성을 분석하는데 목적이 있다. 이를 위해, 본 연구에서는 서울시 도시고속도로에서 비디오촬영을 통해 수집한 실제 데이터(본선 및 램프교통량, 밀도. 속도, 그리고 대기 행렬길이)를 이용하여 진입램프지점의 혼잡상태에서 대기행렬길이가 증가하는 과정을 분석하였다. 분석결과, 흔잡기간중의 대기행렬길이는 혼잡구간에 진입하는 교통량과 병목지점을 실제로 통과하는 교통량을 이용하여 추정이 가능함을 확인하였으며, 혼잡구간의 혼잡정도 역시 실시간으로 수집이 가능한 교통량 자료를 이용하여 신뢰성 있게 판단할 수 있는 분석방법을 제시하였다.

• 수산해양기술연구
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• 제46권4호
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• pp.458-465
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• 2010

Hundreds of Steller sea lions, Eumetopias jubatus, migrate from Sakhalin and the northern Kuril Islands to Hokkaido every winter. During this migration, they may use their roaring sounds to navigate and to maintain their groups. We recorded the roars of wild Steller sea lions that had landed on reefs on the west coast of Hokkaido, and those of captive sea lions, while making video recordings. A total of 300 roars of wild sea lions and 870 roars of captive sea lions were sampled. The fundamental frequency ($F_0$), formant frequency ($F_1$), pulse repetition rate (PRR), and duration of syllables (T) were analyzed using a sonagraph. $F_0$, $F_1$, and PRR of the roars emitted by captive sea lions increased in the order male, female, and juvenile. By contrast, the $F_1$ of wild males was lower than that of females, while the $F_0$ and PRR of wild males and females did not differ statistically. Moreover, the $F_0$ and $F_1$ frequencies for captive sea lions were higher than those of wild sea lions, while PRR in captive sea lions was lower than in wild sea lions. Since there was a linear relationship between body length and the $F_0$ and $F_1$ frequencies in captive sea lions, the body length distribution of wild sea lions could be estimated from the $F_0$ and $F_1$ frequency distribution using a regression equation. These results roughly agree with the body length distribution derived from photographic geometry. As the volume of the oral cavity and the length of the vocal cords are generally proportional to body length, sampled roars can provide useful information about a population, such as the body length distribution and sex ratio.