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.

상호상관 함수를 이용한 지중선로 고장점 추정

朴星完,林泳範,鄭州桓,成洛煥,金喆煥,申明徹 成均館大學校 科學技術硏究所 1994 論文集 Vol.45 No.2

This paper is intended as an investigation of fault location for underground line. Over the past few decades a considerable number of studies have been made on protection of underground line. However, these approaches require the interruption of electric power supply from source for fault location estimation. Therefore, we proposed fault location algorithm for underground line protection without interruption of electric power supply. Cross correlation function is used in this algorithm. Also, EMTP data is used to demonstrate the capability of the proposed fault location algorithm.

동종 골수 이식한 백혈병에서 단반복 유전자로 살펴본 혼합 키메라 현상의 의의

장대영,이정신,서철원,이규형,이제환,지현숙,박찬정,한면수,최동원,김정균,최성준,김성배,김상위,김우건,김상희 대한조혈모세포이식학회 1998 대한조혈모세포이식학회지 Vol.3 No.1

연구배경 : 동종 골수 이식한 백혈병에서 키메라 현상의 분석은 착상, 질병 재발과 이식 거부를 이해하는데 도움을 줄 수 있다. 최근 STR을 PCR로 증폭한 검사법에 의해 매우 민감하고 유용하게 혼합 키메라 현상을 검출할 수 있다고 보고되고 있으나, 이 방법의 민감도와 임상적 의의는 아직 완전히 정립되지는 않았다. 따라서 PCR-STR검사법이 혼합 키메라 현상을 민감하게 검출하는지 보고, 동종 골수 이식 후 혼합 키메라 현상의 변화 양상을 관찰하고, 키메라 현상의 임상적 의의를 보고자 하였다. 방법 : 형제로부터 동종 골수 이식한 급성 백혈병 6명과 만성 백혈병 2명의 모두 8명을 대상으로 하였다. 44개 골수 검체에서 phenol/chloroform방법에 의하여 단핵세포 DNA를 추출하였다. DNA는 CTT 삼중체, vWA와 amelogenin시발체를 이용하여 증폭하였다. 증폭 산물은 5% 폴리아크랄아미드 젤에서 전기영동 뒤 은 염색으로 확인하였다. 2명의 DNA를 여러 비율로 혼합하여 상기 검사를 하여 검출 가능 최소 농도를 결정하였다. 결과 : 상기 검사법의 검출 가능 최소농도는 0.25%였다. 혼합 키메라 현상은 8명중 4명에서 관찰되었다. 혼합 키메라 현상은 보인 1명에서 급성 및 만성 이식편대 숙주 질환이 나타났고, 완전 공여자 키메라 현상을 보인 1명에서 만성 이식편 대 숙주 질환이 나타났다. 점진적으로 증가하는 혼합 키메라 현상을 보인 2명은 이식 후 12개월에 질병 재발을 보였으나, 완전 공여자 키메라 현상을 보인 경우엔 재발이 관찰되지 않았다. 결론 : PCR-STR검사법은 동종 골수 이식 후 남아 있는 환자 세포를 검출하고 키메라 현상을 관찰하는데 유용한 방법이다. 또한 이 검사법은 동종 골수 이식 후 재발의 조기 진단, 이식편 대 숙주 질환의 평가와 면역 관용에 임상적으로 응용할 수 있으리라 생각한다. Background : Chimerism analysis after allogeneic bone marrow transplantation (BMT) for leukemia could be helpful understanding of the early marrow engraftment, disease relapse, and graft rejection. Recently, a PCR technique which amplifies short tandem repeats(STR) has been reported to be highly sensitive and reliable in detecting mixed chimerism. But its sensitivity and clinical significance has not been established. The purpose of this study was firstly, to confirm whether a PCR-STR in highly sensitive enough ti assess mixed chimerism, secondly to monitor the changing patterns of mixed chimerism after allogeneic BMT, and lastly to determine correlation between the chimeric status and the clinical outcome. Methods : A study was made eight patients (six with acute leukemia and two with chronic leukemia) who underwent unmanipulated allogeneic BMT along with matched donors. DNA was extracted from mononuclear cells of 44 bone marrow samples using a phenol/chloroform method. Amplification of DNA was done using CSFIPO-TPOX-TH01(CTT) triplex with or without vWA or amelogenin primer. The amplified product was separated on 5% polyacrylamide gel and was confirmed by silver staining. The sensitivity of CTT triplex method was determined by mixing DNA from two person in serial proportion using the same method. Results : The sensitivity for CTT triplex method was 0.25% Mixed chimerism was documented in 4 of 8 patients. ONe of four patients with mixed chimerism developed acute and chronic graft versus host disease (GVHD) and one of four patients with complete donor chimerism also developed chronic GVHD. Two patient with progressive mixed chimerism relapsed at 12 months post-BMT, whereas no patient with complete donor chimerism has relapsed. Conclusion : The study has found that PCR-STR was an effective method for the detecting residual host cell and monitoring the chimeric status after allogenic BMT. PCR-STR can also be clinically applicable in early prediction of relapse, appropriate assessment of GVHD, as well as tolerance after allogeneic BMT.

서울의 Penicillinase Producing Neisseria Gonorrhoeae 발생빈도(1996)

김재홍,황동규,전재홍,김윤석,김중환,김용준,이창균,임동진,김현수,조창근,김경문,박상훈,전우형,김희성,이호정,차명수,김갑형,김형석,김석우,황지환,박병순,권오상,이민수,송기훈,성소영,이인섭,부태성 대한화학요법학회 1999 대한화학요법학회지 Vol.17 No.2

Background : In recent years, gonorrhea has been panedemic and remains one of the most commom STDs in the world, especially in developing countries. Objective & Methods: For the detection of a more effective therapeutic regimen and assessing the prevalence of PPNG, we have been trying to study the patients who have visited the VD Clinic of Choong-Ku Public Health Center in Seoul since 1980 by means of the chromogenic cephalosporin method. Results: In 1996, 139 strains of N. gonorrhoeae were isolated, among which 53(39.0%) were PPNG. Conclusion: Our results suggests that after a peak of 74.3% in 1993, the prevalence of PPNG in Seoul is gradually declining.

2형 당뇨 환자에 있어서 C형 간염의 유병률에 관한 연구

김구영,서광섭,유광렬,임병욱,채선애,강남훈,김창훈,권영우,김희수,류성태,이정환,박성우,오웅식,김정한 중앙대학교 의과대학 의과학연구소 2003 中央醫大誌 Vol.28 No.1

Background: We have doubt about the truth that Type 2 DM is associated with chronic hepatitis C infection. The aim of our study was to prove a close relationship between chronic HCV infection and type 2 DM in korean patients. Methods: We reviewed the out-patient's medical records of 466 patients with type 2 DM who visit the Sung-ae hospital from March 2000 to August 2001. Diabetic patients were analyzed for the following variables: age, sex, waist circumference, weight, waist/hip ratio, using of self monitoring of blood glucose, method of therapy, duration of disease, experience of previous transfusion, major surgical procedure, accompanied disease, liver function tests (LFT), HbA1 c. We ruled out patients with liver cirrhosis. Results: Hepatitis C virus infection was observed more frequently in patient with Type 2 DM. Of 466 Type 2 DM patients, 13 patients were infected with Hepatitis C virus (2.79%). Compared with mean prevalence of Korean population (1.3~1.6%), it's value is very high. the other hand, 21 patients were infected with Hepatitis B virus (4.5%). Such results are similar to mean prevalence of the general public (4~5%). Conclusions: Prevalence of hepatitis C was closely associated in korean patients with type 2 DM. And an increased prevalence is independent of cirrhosis.

새 자동 안면특성 추출과 인식

정성환 國立 昌原大學校 基礎科學硏究所 1993 基礎科學硏究所論文集 Vol.5 No.-

A new facial-feature extraction and recognition scheme is proposed. It consists of the extraction part using the Gabor wavelet transform and the rule-based recognition part. Our experiment with this system used 25 facial images. The result shows that most mouths and noses can be recognized.

나리屬 식물의 촉성 재배에 있어 엽초 제거가 생육에 미치는 영향

정우윤,최상태,박인환,김성태,박현근 慶北大學校 農業科學技術硏究所 2003 慶北大農學誌 Vol.21 No.-

The study aimed to identify leaf sheath through the investigation a characteristic of leaf by planting depth and leaf sheath function through the investigation of effect of leaf sheath removals on growth and flowering in forcing of Lilium cultivars. The number of leaf sheath of 'Jolanda', 'Dream Land', 'Casablanca' were 6, 5, 11 in 0㎝ planting depth and 6, 5, 14 in 6㎝ planting depth. The number of leaf sheath in 'Jolanda' and 'Dream Land' were little different in according to planting depth. The other hand, the number of leaf sheath in 'Casablanca' were increased 3 when it were planted in 6㎝ planting depth. As leaf sheath were removed, plant height and stem root growth were decreased in 'Le Reve' and 'Casablanca'. Whereas the growth of basal root and flower number varied among of Lillium and stem diameter, the days of flowering and flower size were little different.

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.

액체막법에 의한 중금속이온의 분리 및 회수

曺文換,丁學鎭,이상인,金振浩,金始中 江原大學校 附設 環境硏究所 1994 環境硏究 Vol.11 No.-

거대고리 리간드는 금속이온과 선택적으로 결합하는데, 이를 이용하여 에멀젼 액체막을 통한 금속이온의 이동에 관하여 연구를 수행하였다. 금속이온은 유기층에 있는 운반체에 의하여 source phase에서 receiving phase으로 이동한다. 운반체로는 거대고리 리간드인 DBN_(3)O_(3)를 사용하였다. 여기에서 에멀젼 액체막을 통한 금속이온의 이동에 관한 요인과 어떤 금속이온의 선택적 분리에 관하여 검토하였다. 금속이온과 거대고리 리간드 그리고 금속이온과 receiving phase내에 있는 음이온에 대한 안정도 상수를 금속이온의 선택적 이동에 대한 척도로 조사하였다. 납이온이 혼합 용액에서 다른 금속이온보다 높은 이동속도를 나타내었다. Receiving phase내의 음이온이 금속이온의 이동에 중요한 역할을 한다. Receiving phase내에 있는 NO_(3)^(-)을 S_(2)O_(3)^(2-) 대치하면 이동량이 증가함을 보였는데 이는 Pb^(2-)-S_(2)O_(3)^(2-) 상호작용이 Pb^(2+)-NO_(3)^(-) 상호작용보다 크기 때문이다. Macrocyclic ligand has been know to selectively bind with metal ions so that ability applied for the transport of metal ions across the emulsion liquid membrane in this study. The metal ions are transproted from the source phase to the receiving phase by the carrier of the organic phase. Several factors involved in the transport of metal ions acrose the emulsion membrane we reported here and these factors proveided the informations for the selective seperation of some metal ion. Stability constants for cation-macrocyclic ligand and metal ion-anion receiving phase interaction are examined as parameters for the prediction of metal ion transport selectivities Pb^(2+) was transported higher rates than the other metal ions in the mixture solution. The interaction of metal ion to anion in receiving phase is important. S_(2)O_(3)^(2-) in replacement of NO_(3)^(-) in the receiving phase enhances the transport of pb^(2-) since Pb^(2-)-S_(2)O_(3)^(2-) interaction is greater than Pb^(2+)-NO_(3)^(+) interaction.

근사 DCT를 사용한 훼손된 영상 데이타의 압축 연구

정성환,팽영혜 昌原大學校 基礎科學硏究所 1996 基礎科學硏究所論文集 Vol.8 No.-

Image compression techniques are very important for storing and transmitting image data which require, in general, a lot of storage space and transmitting time. In this paper, we investage the compression performance of an approximate DCT to the degraded images with Gaussian noise, impulse noise, and BSC noise. Using real images, the performance of the approximate DCT is compared with that of the standard DCT. As the result of experiment, it shows less blocking artifact and faster than the conventional DCT.