TMS320C6201을 이용한 적응 다중 전송율을 갖는 광대역 음성부호화기의 실시간 구현

이승원,배건성,Lee, Seung-Won,Bae, Keun-Sung 한국통신학회 2004 韓國通信學會論文誌 Vol.29 No.9C

본 논문에서는 적응 다중 전송율을 갖는 광대역 음성부호화기인 AMR-WB 의 알고리즘을 분석하고, TI사의 고정소수점 DSP인 TMS320C6201를 이용한 실시간 구현 결과를 제시한다. AMR-WB 음성부호화기는 두 가지 대 역으로 분리된 신호가 독립적으로 부호화되며, 저대역 신호는 ACELP 방식으로、 고대역 신호는 잡음 여기신호와 선형예측 합성필터를 사용하는 방식으로 각각 합성된다. 구현된 AMR-WB 음성부호화기는 프로그램 메모리와 데이터 메모리가 각각 218 kbytes, 92kbytes의 크기를 가지며 , 한 프레임인 20 ms를 처리하는데 평균 920,267 정도의 클릭 수가 사용되어 약 5.75 ms의 시간이 소요 되였다. 또한, DSP로 구현한 AMR-WB 음성부호화기의 결과와 PC에서 시뮬레이션 한 결과가 서로 일치함을 확인하였다. This paper deals with analysis and real-time Implementation of a wide band adaptive multirate speech codec (AMR-WB) using a fixed-point DSP of TI's TMS320C6201. In the AMR-WB codec, input speech is divided into two frequency bands, lower and upper bands, and processed independently. The lower band signal is encoded based on the ACELP algorithm and the upper band signal is processed using the random excitation with a linear prediction synthesis filter. The implemented AMR-WB system used 218 kbytes of program memory and 92 kbytes of data memory. And its proper operation was confirmed by comparing a decoded speech signal sample-by-sample with that of PC-based simulation. Maximum required time of 5 75 ms for processing a frame of 20 ms of speech validates real-time operation of the Implemented system.

경량 비디오 코덱을 위한 3D 웨이블릿 코딩 기법

이승원,김성민,박성호,정기동,Lee, Seung-Won,Kim, Sung-Min,Park, Seong-Ho,Chung, Ki-Dong 한국정보처리학회 2004 정보처리학회논문지B Vol.11 No.2

비디오 압축에 사용되는 움직임 예측은 많은 계산과정을 요구하기 때문에 전체적인 부호기 복잡도를 높이는 단점을 지닌다. 이러한 부호기의 복잡도를 줄이기 위해 3D-WT과 같은 움직임 예측을 사용하지 않는 연구들이 소개되고 있다. 하지만, 기존의 3D-WT 기법들은 부호화를 위한 과도한 메모리 요구사항과 복호를 위한 수신 측의 지연시간이 가장 큰 단점으로 지적되었다. 본 논문에서는 수정된 Haar wavelet filter와 개선된 부호화 알고리즘을 통해서 메모리 사용량과 재생을 위한 지연시간을 최소로 하는 확장 가능한 3D-WT 기법인 FS(Fast playable and Scalable) 3D-WT를 소개한다. 3D-WT 중 가장 개선된 형태인 3D-V 기법과의 실험 결과 3D-V와 거의 비슷한 계산 처리 시간으로 높은 압축률과 수신 측에서의 짧은 지연시간을 보였다. It is a weak point of the motion estimation technique for video compression that the predicted video encoding algorithm requires higher-order computational complexity. To reduce the computational complexity of encoding algorithms, researchers introduced techniques such as 3D-WT that don't require motion prediction. One of the weakest points of previous 3D-WT studies is that they require too much memory for encoding and too long delay for decoding. In this paper, we propose a technique called `FS (Fast playable and Scalable) 3D-WT' This technique uses a modified Haar wavelet transform algorithm and employs improved encoding algorithm for lower memory and shorter delay requirement. We have executed some tests to compare performance of FS 3D-WT and 3D-V. FS 3D-WT has exhibited the same high compression rate and the same short processing delay as 3D-V has.

망막정맥폐쇄와 당뇨망막병증에서 황반부종 치료를 위한 유리체내 베바시주맙 주입술의 효과

이승원,김무상,김응석,곽형우,유승영,Seung Won Lee,MD,Moo Sang Kim,MD,Eung Suk Kim,MD,Hyung Woo Kwak,MD,Seung Young Yu,MD 대한안과학회 2009 대한안과학회지 Vol.50 No.2

Purpose: To evaluate the long-term results of intravitreal bevacizumab injection for macular edema (ME) due to retinal vein obstruction (RVO) and diabetic retinopathy (DR). Methods: The objects of study were patients with decreased visual acuity due to ME with RVO and DR for whom intravitreal injections of 1.25 mg (0.05 ml) bevacizumab were repeated three times with an interval of six weeks and who were available for a follow-up period of more than 12 months. The patients underwent additional bevacizumab injections if ME increased as assessed by optical coherence tomography (OCT). Best-corrected visual acuity (BCVA) and central macular thickness (CMT) were measured at baseline and follow-up visits. Results: There were 16 patients with RVO and 18 patients with DR. In the RVO group, the mean length of follow-up was 12.4±1.1 months, the mean baseline BCVA was 0.75±0.32 and the final BCVA was 0.42±0.25, a difference that was statistically significant (p<0.05). The mean CMT at baseline was 588.5±301.0 μm and this decreased to a mean of 191.8±112.0 μm at the end of the follow-up period (p<0.05). In the DR group, the mean length of follow-up was 15.4±3.2 months, the mean baseline BCVA was 0.63±0.33 and the final BCVA was 0.61±0.37, a difference that was not statistically significant (p>0.05). The mean CMT at baseline was 462.0±195.0 μm and decreased to a mean of 282.2±177.3 μm at the end of the follow-up period (p<0.05). Conclusions: In RVO and DR, three injections of intravitreal bevacizumab with an interval of six weeks and additional injections as indicated were effective in reducing ME and showed especially good results in improvement of visual acuity for ME due to RVO.

수축형 수차발전기 축진동에 관한 연구(I)

이승원(Lee Sung Won) 대한전기학회 1964 전기의 세계 Vol.13 No.3

It is the intention of this thesis to discriminate and investigate the cause of the shaft vibration of the vertical type hydroelectric power generator with respect to electrical, mechanical and hydraulic aspects, and to analyze the vibration which will occure by the each cause investigated above. In order to test the shaft vibration of No.1 generator in Hwachon, Korea new measurement method and measuring equipments were designed. In practice the shaft vibration of the generator was measured by above equipments and analyzed by the discriminative method. Detailed explanation for the designed measurement method and instruments is presented, and the results which I had tested three times for the generator No.1 in Hwachon power plant are added. As a appendix the mechanism and causes of the thrust bearing's wear and remarks for the runner are written.

수축형 수차발전기 축진동에 관한 연구 (II)

이승원(Lee Sung Won) 대한전기학회 1964 전기의 세계 Vol.13 No.4

수차발전기에서 이상진동이 발생하였을 경우 일반적인 진동판별법을 서술하기로 한다. 실제로 부디치는 진동문제를 취급하여 보면 단순한 원인에 의한 것 뿐만아니라 여러가지 원인이 중첩되어 복잡한 비선형적인 현상이 나타날 경우가 많다. 원동기측 및 피동기측의 회전자급 고정자의 각각에 진동을 발생하는 다수의 요인이 있고 또 각각의 진동원인들의 상호간의 영향력이 작용하여 복잡한 진동현상을 가지고 있어서 그 원인을 판별하기가 용이한 일이 아니다. 이러한 진동원인중 주 되는 몇가지 원인을 찾아내기 위하여는 진동특성에 관한 충분한 이해와 적절한 측정장치를 선택할 필요가 있다.

산간지역 매립장의 침출수에 의한 지하수오염 거동 특성

이승원 ( Seung-won Lee ),박남배 ( Nam-bae Park ),이상용 ( Sang-yong Lee ),박성현 ( Sung-hyun Park ),김정권 ( Jung-kwon Kim ) 한국환경기술학회 2012 한국환경기술학회지 Vol.13 No.4

본 연구는 경상남도 사천군 주위 산간지역의 수리학적 특성 및 지하수위 변동 등의 인자를 이용하여 지하수 흐름 및 매립장 침출수 이동을 GMS 7.0모델을 통해 재현하고 미래에 예상되는 변화를 예측하는 것이 목적이다. 대상영역은 1,510m×1,270m로서 151column과 127row로 세분화하였다. 또한 Cl^-이온 4,000mg/L를 매립장 운영기간(23년) 동안 연속적으로 발생한다고 가정하여 모델링 하였으며, 오염물질 거동을 파악하기 위해 매립장 인근 4개소의 감시정을 설치 한 후 오염물질 농도를 관측하였다. 본 모델링 지역의 남서 및 북서방향은 산계로 이루어져 있어 남동방향으로 지하수가 유동하는 양상을 보이고 있다. 이때 Cl^- 400mg/L가 매립장에서 유출되는 4개의 감시정 중 COW2(남동방향)최대 539.84mg/L로 발생되었으며, 이는 다른 3방향의 감시정에 비해 약 2.6~3배 높은 것으로 나타났다. 결과적으로 산간지역의 경우 연직 차수벽 훼손 시 지하수 유동에 따라 오염물질이 빠르게 확산되므로 지하수 거동 특성이 매우 중요하다. The purpose of this research is to forecast the future variation and to reproduce for movement of leachate landfill and ground water flow by means of using ground water head and hydraulic character of mountain area around in Gyeongsangnam-do Sacheon -gun through GMS 7.0 Model. This domain area is 1510 m × 1,270 m which is subdivided into 151 column and 127 row. It is modeled that 4,000mg/L Cl^- ion is continuously discharged during the landfill operating period for 23 years. In order to observe Cl^- ion, four monitoring systems were installed around the landfill. According to the result of Modflow, as the modeling area for southwest and northwest is consisted mountainous district, ground water is flowing to southeast direction. At this time, Cl^- ion the outflow from the landfill was observed max 539.84 mg/L at COW2(southeast) monitoring system. It was surveyed that Cl^- ion concentration is roughly 2.6~3 times higher, compared with other monitoring systems(COW1, COW3 and COW4). As a results, mountains area is very important to consider the ground water flow characteristics when vertical impermeable wall is torn specially. Since, the landfill leachate flows very fast with ground water flow.

침투도랑 시설의 유지관리 시점 산정방법에 관한 연구

이승원 ( Seung Won Lee ),차성민 ( Sung Min Cha ) 한국물환경학회(구 한국수질보전학회) 2020 한국물환경학회지 Vol.36 No.1

To manage the non-point source pollution and restore the water circulation, many technologies including infiltration or reservoir systems were installed in the urban area. These facilities have many problems regarding maintenance as their operation period becomes lengthier. The purpose of this study was to estimate the optimal maintenance timing through a long-term load test on the infiltration trench as one of the low impact development techniques. An infiltration trench was installed in the demonstration test facility, and stormwater was manufactured by Manual on installation and operation of non-point pollution management facilities from the Ministry of Environment, Korea and entered into the infiltration trench. Particle size distribution (PSD), suspended solids (SS) removal efficiency, and infiltration rate change tests were performed on inflow and outflow water. In case of the PSD, the maximum particulate size in the outflow decreased from 64 μm to 33 μm as the operating duration elapsed. The SS removal efficiency improved from 97 % to 99 %. The infiltration rate changed from 0.113 L/sec to 0.015 L/sec during the operation duration. The maintenance timing was determined based on the stormwater runoff requirements with these changes in water quality and infiltration rate. The methodologies in this study could be used to estimate the timing of maintenance of other low impact development techniques.

전류 피드백을 이용하여 주파수 동작범위와 노이즈 특성을 향상시킨 홀센서 인터페이스 계측 증폭기 설계에 대한 연구

이승원(Seung-Won Lee),손상희(Sang-Hee Son) 한국정보기술학회 2020 한국정보기술학회논문지 Vol.18 No.8

In this paper, we proposed an interface instrumentation amplifier circuit structure that can increase the operating frequency range by using chopper and current feedback in the fully differential amplifier structure and reduce power consumption. It is easy to use independent input and output common mode voltages and the high CMRR of a size similar to that of the previous circuit is maintained at the same time. A chopper circuit is additionally used to suppress the generation of 1 / f noise generated at low noise and low frequency. At the same time, a filter was added between the output of the instrumentation amplifier circuit and the two-stage amplifier to eliminate ripples occurring at the chopping frequency. This prevented the inflow of ripple voltage. To use the this structure, it was possible to operate in 10 times higher frequency range than the conventional amplifier. The amplifier circuit proposed in this paper was performed and verified by computer simulation using 0.18㎛ TSMC CMOS process technology.

적응 극점 배치에 의한 로보트 매니퓰레이터 제어

이승원(Seoung-Won Lee),이종용(Chong-Young Lee),양태규(Tae-Gyu Yang),이상효(Sang-Hyo Lee) 대한전기학회 1987 대한전기학회 학술대회 논문집 Vol.1987 No.7

E종 절연 유도 전동기의 설계

이승원(Sung Won Lee) 대한전기학회 1967 전기의 세계 Vol.16 No.2

From the discovery of Alago's disk, a number of trials and efforts have been concentrated on a small-sized and light-weighted induction motor. They have devoted themseleves, however, mainly to a improvement of cooling effect, a proper weight-distribution of copper and iron and desirable number of slots. In consequence, such an effort restricted only to the field of design, has resulted in unsatisfactory developments in the insulating materials consisting of the main parts of an induction motor. The quality of fibre and paper which are used as class-A insulation materials with their "compound" and "varnish" has been increased to some extent. Similarly Class-B insulation materials like asbest mica has been almost a combination of inorganic and binding materials. But nowadays synthesic chemistry is making a remarkable progress. So it comes possible for us to have silicon resin and other good ones of similar charateristics. And even a thin silicon resin insures us to get excellent heat-pro f and insulation, so a better space factor and cost-down in motor design have come possible in most advanced nations of the world, but not in our country. Furthermore, a consideration of productivity and economy in manufacturing process has been neglected by a majority of engineers. This is more unpleasant und more undesirable. I think this rational method of induction motor design using new synthesic resin will devote in making your productivity and economy better. And the nation-wide standard value of electric motor size is sited here. size is sited here.