http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Improved DCT-Based Image Coding and Decoding Methods For Low-Bit Rate Applications
Jung, Sung-Hwan,Sanjit K. Mitra 國立 昌原大學校 基礎科學硏究所 1994 基礎科學硏究所論文集 Vol.6 No.-
The discrete cosine transform (DCT) is well known for highly efficient coding performance, and it is widely used in many image compression applications. However, in low-bit rate coding, it produces undesirable block artifacts that are visually not pleasing. In addition, in many applications, faster computation and easier VLSI implementation of DCT coefficients are also important issues. The removal of the block artifacts and faster DCT computation are therefore of practical interest. In this paper, we outline a modified DCT computation scheme that provides a simple efficient solution to the reduction of the block artifacts while achieving faster computation. We also derive a similar solution for the efficient computation of the inverse DCT. We have applied the new approach for the low-bit rate coding and decoding of images. Initial simulation results on real images have verified the improved performance obtained using the proposed method over the standard JPEG method.
정연택,한경희,이승환,김성남 明知大學校 産業技術硏究所 1987 産業技術硏究所論文集 Vol.6 No.2
This paper, in case of chopper controlling D.C. Motors, suggested three phase chopper system in order to reduce a source current and amature current ripple, and it's characteristic proves study on the theory and experiment. As a result of consideration, it was found that chopper system had reduced current ripple compare with two phase chopper system and impressed voltage of motor could be continuously controlled from 0 to the source voltage by adjusting chopper's time ratio α from 0 to 1.
ADALINE을 이용한 훼손된 영상에 대한 에지검출 연구
鄭聖煥,禹容泰 國立昌原大學校 基礎科學硏究所 1992 基礎科學硏究所論文集 Vol.3 No.-
The edge detection technique using neural network is discussed for some noisy images. It is compared with conventional edge detection techniques by the subjective measure and objective. The edge detection technique of neural network shows better performance than others in some noisy environments.
근사 DCT와 움직임 보상을 이용한 연속 영상 부호화 기법 연구
정성환 國立昌原大學校 基礎科學硏究所 1994 基礎科學硏究所論文集 Vol.6 No.-
A simple and fast image coding technique using an approximate DCT and a motion compensation is proposed. Through the experiment using a real image sequence SALESMAN, it shows faster performance and less blocking effects than the conventional DCT-based sequence coding method.
항공기 엔진용 Ti-6Al-4V합금의 열화학적 방법을 통한 미세조직 개선에 관한 연구
정성환,김광배 한국 항공대학교 항공산업기술연구소 1996 航空宇宙産業技術硏究所 硏究誌 Vol.6 No.-
This paper is aimed for grain refinement of Ti-6Al-4V alloy used in aircraft engine part with thermochemical processing. Ti alloys can be hydrogenated with large amount of hydrogen at relatively elevated temperature and hydrogen is simply removed by a vacuum annealing to levels below which no detrimental effects occur. The presence of hydrogen allows the titanium alloy to be processed at lower temperature due to the increace of β phase volume fraction and enhanced mechanical properties because of grain refinement caused by recrystallization after heat treatment. This study determines optimum procedures of thermochemical processing to improve mechanical properties of Ti-6Al-4V.
오디오와 영상 정보를 이용한 비디오 샷, 장면 경계 검출 및 크래시피케이션
정해준,정성환 창원대학교 정보통신연구소 2001 精報通信論文集 Vol.5 No.-
본 논문에서는 효과적인 내용기반 비디오 검색을 위한 샷 경계 검출, 장면 경계 검출, 그리고 비디오 크래시피케이션 방법을 연구하였다. 먼저, 샷 경계 검출을 위해 칼라 히스토그램과 DCT변환 계수를 통합하여 사용했다. 그리고 장면 경계 검출을 위해서는 영상 정보뿐만 아니라 오디오 정보를 함께 사용하여 장면 경계를 검출하였다 또한 비디오 크래시피케이션에서는 장면 경계 검출시 추출한 오디오 정보를 이용해 비디오를 내용별로 분류하는 연구를 제안하였다. 뉴스, 광고, 스포츠 등 다양한 3개 분야의 TV 프로그램으로 구성된 약 8,500개 영상 프레임과 약 50,000개의 오디오 프레임을 가진 실험 비디오 데이터베이스를 구성하여 제안된 시스템을 실험하였다. 실험한 결과, 약 88%의 정확도(Precision)를 가지는 장면 경계 검출과 약 85%의 평균 분류율을 보였다.
콩 단백질/펙틴/몬모릴로나이트 나노복합 필름의 특성 및 산소 투과도 연구
정세환,김성철,조규순,신용섭,장상희,홍기헌,이태진,신부영 嶺南大學校 工業技術硏究所 2004 工業技術硏究所論文集 Vol.32 No.2
In this study, Mechanical property, thermal property, watervapor, and oxygen permeability of biodegradable Soy protein/Pectin-montmorillonite nanocomposite, prepared with Na^(+)-MMT, have been studied. X-ray diffraction and TEM experiments an polymer/silicate composite samples demonstrated that the intercalation of polymer chains leads to increase in the spacing between silicate layers. In addition, it were found that the intercalated Soy protein/Pectin/montmorillonite nanocomposite were prepared. It was found that the addition of only a small of clay was enough to improve the thermal stability and mechanical property of Soy protein/Pectin/montmorillonite nanocomposite. watervapor of Soy protein/Pectin/montmorillonite nanocomposite was generally lower than that of Soy protein/Pectin. oxygen permeability of Soy protein/Pectin/montmorillonite nanocomposite was generally lower than that of Soy protein/Pectin.
유방통을 호소하는 한국 여성에서 Gamma Linolenic acid의 임상적인 효과
정재헌,김권천,조현진,민영돈,김성환,김정용,장정환 조선대학교 부설 의학연구소 2000 The Medical Journal of Chosun University Vol.25 No.1
Background and Objectives : Recently, the incidence of breast cancer is gradually increasing in korea. Many patients visit the hospital with a fear of breast cancer, if she had the pain in her breast. But Breast pain is not a cardinal sign of breast cancer. Only 7% of patient in breast cancer has breast pain. Materials and Method : To know the clinical effects of gamma-linolenic acid(GLA), we analyzed the medical records of 55 cases with breast pain, who visited the outpatient clinic of Chosun university hospital, between July of 1999 to December of 1999. Of the 55cases of breast pain, we analyzed 26 cases of patient with breast pain who was treated with GLA for 2 month and we excluded patients of breast pain who had breast mass or were treated with other drug. Results : 2 Patients we are dropped out because nausea and vomiting were developed, 4 Patient with breast pain were treated with GLA for 1 month, and relieved completely from mastalgia and 8 patients with breast pain were treated with GLA for 2 months and breast pain was relieved completelys. 4 patient had treatment for 2 months, were relieved slightly. But 8 patients with breast pain didn't reveal the relief of symptom after the intake of GLA. Conclusion : We conclude that GLA could be considered a first line drug in patients with mastalgia.
대구지역 금호강 및 주요 지천 퇴적물의 시·공간적 독성변화
정홍배,문성환,정진애,김재현,박정규,배철한,황인영 한국환경독성학회 2001 환경독성보건학회지 Vol.16 No.4
1. 사전에 선정된 공통 조사 정점들 가운데 KㆍH4(금호대교)이후의 퇴적물 독성이 상부의 것보다 크게 나타났다. 즉, 정점 KH3과 KH4, 그리고 KH4와 KH5 사이에 독성물질 유입원이 있는 것으로 판단되었다. 2. 하천 퇴적물의 독성 수준에 영향을 주고 있는 물질의 종류와 배출원 파악이 필요하였다. 이러한 내용을 향후 계속적 연구 및 조사를 통하여 수행되어야 하는 과제라 사료된다. 3. 퇴적물 시료의 채취 시점에 따라서 동일 정점의 독성 변화가 심하였다. 유해화학물질에 의한 오염 수준과 하천 생태계의 영향을 예측하기 위해서는 하천 퇴적물을 대상으로 경시적으로 독성의 변화를 계속 관측하는 것이 필요하다고 판단되었다. In aqueous ecosystems, the level of toxicity is highly responsive dependant to multiple variables, including rainfall, sunlight, pH, adhesion, etc. Because Korea has particularly distinct wet and dry seasons, the toxicity of pollutants in rivers or streams is dependant on the sampling season and time. In order to examine the effects of rainfall on toxicity, sediment samples were collected from five sites along the Keumho river. It was found that Microlox toxicity levels were generally higher during the dry season than the wet season. It indicated that river pollutants are carried off more quickly by the water during the wet season. As a result, it was recommended that the point sources of pollutants of the Keumho river would be placed between KH3 (Paldalgyo) and KH4 (Keumhogyo), KH4 (Keumhogyo) and KH5 (Dasa).