묘성증후군 환아 1예에서 관찰된 안과적 소견

김상균,김형석,김승현,Sang Kyoon Kim,Hyoung-Seok Kim,Seung Hyun Kim 대한안과학회 2008 대한안과학회지 Vol.49 No.11

돈(豚)의 간회충증(肝蛔蟲症)에 관(關)한 병리학적(病理學的) 검색(檢索)

김상균,임창형,Kim, Sang Kyun,Lim, Chang Hyeong 대한수의학회 1970 大韓獸醫學會誌 Vol.10 No.1

1. Hepatic ascariasis represented by milk spots on the liver surface was found in 475(31.7%) out of 1,500 pigs. 2. For histopathological studies, 170 cases were collected at random from the milk spotted liver From these cases ascaris larva was found in 14 cases(8.2%). 3. Grossly, the occurrence of milk spots was not confined to any particular lobes of the liver. The lesions, however, were more frequently found in the diaphragmatic surface than in the visceral surface. The extent of the spots was limited to the subcapsular region and the deeper tissue was not affected. 4. Histologically, hemorrhage and eosinophilic infiltration were observed in the area invaded by the larva. The increase of connective tissue followed by a form of chronic lymphocytic hepatitis was observed at the late stage of infection. There was numerous eosinophilic infiltration around the larva trapped in the liver tissue. Consequently, encapsulation of the larva was followed by organization and calcification.

재발된 간헐외사시에서 순응도에 따른 부분가림치료의 장기적 효과

김상균,이승태,김승현,조윤애,Sang Kyoon Kim,MD,Sung-Tae Yi,MD,Seung-Hyun Kim,MD,PhD,Yoonae A,Cho,MD,PhD 대한안과학회 2009 대한안과학회지 Vol.50 No.1

Purpose: To evaluate the reoperation rate and the change of exo-angle according to compliance level of part time occlusion therapy in recurrent intermittent exotropia. Methods: This retrospective study included 52 patients of recurrent intermittent exotropia who followed up more than 5 years after their first operation. They were ordered part time occlusion therapy for recurrent exotropia. The patients were divided into 4 groups according to the level of compliance of part time occlusion therapy (\'excellent\', \'good\', \'fair\', \'poor\'). We evaluated the reoperation rate in 5 years after the first operation and the change of exo-angle from the early recurrent time according to compliance levels. Results: The reoperation rate within 5 years after the first operation of \'excellent\' and \'good\' compliance groups was lower than that of \'fair\' and \'poor\' groups (33.3, 26.3, 73.7 and 45.5% respectively) and the degree of exo-angle progression from the early recurrent time of the \'excellent\' and \'good\' compliance groups was less than that of \'fair\' and \'poor\' compliance groups, both results of which were statistically significant (p=0.02, 0.03). Conclusions: Part time occlusion therapy in recurrent intermittent exotropia has good long-term effects of decreasingreoperation rates in patients with a high level of compliance.

LPCVD 장치를 이용한 메탄과 수소 혼합기체로부터 다이아몬드 박막의 제조

김상균,최진호,주광열,Kim Sang Kyun,Choy Jin-Ho,Choo Kwng Yul 대한화학회 1990 대한화학회지 Vol.34 No.5

일반적인 화학증기증착(CVD : Chemical Vapor Deposition)실험에서 반응기작을 연구할 수 있는 LPCVD (Low Pressure CVD) 장치의 설계 및 제작에 관한 것과, 특히 이 장치를 이용하여 메탄, 수소의 혼합기체와 헬륨을 완충(buffer) 가스로 사용하여 p-type (111) Si wafer 위에 다이아몬드 박막(diamond film)을 얻고자 시도한 것에 대하여 기술하였다. 실험은 두 가지 방법으로 나누어서 행하였다. (1) Si wafer를 반응기 안에 있는 heater(약 480$^{\circ}C$)위에 놓고 두 개의 다른 inlet 가스관을 사용하여 실험하였다. Posphoric acid로 coating된 하나의 관은 microwave discharge시킨 수소 기체를 흘려주는데 사용하였고, 다른 관은 discharge시키지 않은 메탄 기체를 흘려주는데 사용하였다. 그 결과로 무정형 탄소 뭉치 화합물(amorphous carbon cluster)을 얻었다. (2) 수소와 메탄을 동시에 discharge시켜 plasma 상태인 discharge tube안에 Si wafer을 넣고 증착시켜, 그 결과로 다이아몬드 구조를 갖은 반응생성물을 얻었다. We describe how to design and construct a LPCVD (Low Pressure Chemical Vapor Deposition) apparatus which can be applicable to the study of reaction mechanism in general CVD experiments. With this apparatus we have attempted to make diamond like carbon films on the p-type (111) Si wafer from (H$_2$ + CH$_4$) gas mixtures. Two different methods have been tried to get products. (1)The experiment was carried out in the reactor with two different inlet gas tubes. One coated with phosphoric acid was used for supplying microwave discharged hydrogen gas stream, and methane has been passed through the other tube without the microwave discharge. In this method we got only amorphous carbon cluster products. (2) The gas mixture (H$_2$ + CH$_4$) has been passed through the discharge tube with the Si wafer located in and/or near the microwave plasma. In this case diamond-like carbon products could be obtained.

IQ Imbalance와 위상 잡음을 고려한 OFDM 통신 시스템의 성능 분석

김상균,유흥균,강병수,이광천,Kim, Sang-Kyun,Ryu, Heung-Gyoon,Kang, Byung-Su,Lee, Kwang-Chun 한국전자파학회 2007 한국전자파학회논문지 Vol.18 No.7

OFDM(Orthogonal Frequency Division Multiplexing) 시스템은 이동성이 있는 고속 데이터 전송에 적합한 전송 방법으로 널리 알려져 있지만, 위상 잡음과 직교 불균형(IQ imbalance)에 매우 민감한 특성을 보이는 단점이 있다. 그러므로, 본 논문에서는 위상 잡음 특성에 따른 위상 잡음 분산을 계산한 다음, 직교 불균형이 있는 OFDM 시스템의 통신 성능을 분석하였다. 시뮬레이션 결과, 위상 잡음의 분산과 직교 불균형의 크기 변화에 따라 통신 성능이 변화하는 것을 분석하였다. 분석 결과, 진폭 불균형이 ${\varepsilon}$=0.2; 0.3; 0.4이고, 위상 불균형이 ${\phi}=10^0$이고, 위상 잡음의 분산 ${\sigma}^2=0.012$일 때, BER은 $10^{-5}$에서 각각 2.88 dB, 3.61 dB, 4.69 dB의 SNR penalty가 존재한다. OFDM system is an excellent high speed transmission method but it is seriously sensitive to the phase noise and IQ imbalance. Therefore, in this paper, we analyze the communication performance of the OFDM communication system with IQ imbalance and phase noise. Phase noise's variance can be calculated by integral calculus of phase noise power spectrum. From simulation results, it can be shown that the BER performances show different change according to the phase noise variance and IQ imbalance amount. When amplitude imbalance is ${\varepsilon}$=0.2; 0.3; 0.4 and phase imbalance is ${\phi}=10^0$, and distribution of phase noise is ${\sigma}^2=0.012$, BER is degraded by 2.88 dB, 3.61 dB, 4.09 dB in $10^{-5}$ in the respect of the SNR penalty.

SMV코덱의 음성/음악 분류 성능 향상을 위한 최적화된 가중치를 적용한 입력벡터 기반의 SVM 구현

김상균,장준혁,조기호,김남수,Kim, Sang-Kyun,Chang, Joon-Hyuk,Cho, Ki-Ho,Kim, Nam-Soo 한국음향학회 2009 韓國音響學會誌 Vol.28 No.5

본 논문에서는 변별적 가중치 학습 (discriminative weight training) 기반의 최적화된 가중치를 가지는 입력벡터를 구성하여 support vector machine (SVM)을 이용한 기존의 3GPP2 selectable mode vocoder (SMV)코덱의 음성/음악 분류 성능을 향상 시키는 방법을 제안한다. 구체적으로, 최소 분류 오차 minimum classification error (MCE) 방법을 도입하여, 최적화된 가중치를 각각의 특징벡터별로 부가한 SVM을 적용하여 기존의 가중치를 고려하지 않은 SVM 기반의 알고리즘과 비교하였으며, 우수한 음성/음악 분류 성능을 보였다. In this paper, we apply a discriminative weight training to a support vector machine (SVM) based speech/music classification for the selectable mode vocoder (SMV) of 3GPP2. In our approach, the speech/music decision rule is expressed as the SVM discriminant function by incorporating optimally weighted features of the SMV based on a minimum classification error (MCE) method which is different from the previous work in that different weights are assigned to each the feature of SMV. The performance of the proposed approach is evaluated under various conditions and yields better results compared with the conventional scheme in the SVM.

확률유한요소 해석에 의한 근접터널 안정성 분석

김상균,Kim, Sang-Gyun 한국터널지하공간학회 2008 한국터널지하공간학회논문집 Vol.10 No.4

본 논문에서는 탄소성 유한요소해석 알고리즘과 연계한 확률장 생성기법과 근접터널 조건에서의 파괴확률을 분석하였다. 유한요소 해석을 위한 이산 확률장의 생성은 빠르고 정확하며 랜덤변수의 해상도를 자유롭게 조절할 수 있는 local average subdivision 기법을 사용하였으며 터널모델링을 위해 유한요소 크기와 형상 변화 등을 적절히 고려하여 지반물성치를 적용하는 방안을 제안하였다. 예제해석 조건에 대해 강도정수의 분산정도 및 공간상관길이에 따른 파괴확률을 파악하였으며 결정론적 안정성 해석결과 및 단일랜덤변수 해석결과와 비교하였다. 강도정수의 분산특성에 따라 강도감소기법에 의한 안전율과 단일랜덤변수 해석에 의한 파괴확률의 관계를 규명하였으며 확률유한요소 해석을 통해 공간상관길이가 파괴확률에 미치는 영향을 분석하였다. 이를 통해 강도감소기법에 의한 안전율과 분산계수로부터 단일랜덤변수에 의한 파괴확률을 도출할 수 있었으며 단일랜덤변수 해석결과가 근접터널의 실제적인 파괴확률을 과소평가 할 수 있음을 파악하였다. In this paper, the modeling procedure of random field with an elasto-plastic finite element algorithm and probability of failure on closely-spaced tunnel were investigated. Local average subdivision (LAS) method which can generate discrete random variables fast and accurately as well as change the resolution in certain region was used. And correlated value allocating and weighted average method were suggested to implement geometrical characteristics of tunnel. After the probability of failure on the test problem was thoroughly investigated using random finite element method, the results were compared with the deterministic strength reduction factor method and single random variable method. Of particular importance in this work, is the conclusion that the probability of failure determined by simplified probabilistic analysis, in which spatial variability is ignored by assuming perfect correlation, can be estimated from the safety factor determined by strength reduction factor method. Also, single random variable method can lead to unconservative estimates of the probability of failure.

SET에 대한 이해

김상균,Kim, Sang-Gyun 한국데이터베이스진흥원 1997 디지털콘텐츠 Vol.12 No.-

전자상거래의 사실상의 보안표준 프로토콜로 부상하고 있는 SET에 대해 그 구체적인 모습과 역할, 구성요소에 대해 알아보도록 하겠다.

개질 비대칭 폴리에테르이미드막을 통한 물-이소프로판올 혼합물 투과증발 분리: NaOH용액의 농도와 개질반응 시간에 따른 몰폴로지 변화

김상균,제갈종건,이규호,Kim, Sang-Gyun,Jegal, Jonggeon,Lee, Kew-Ho 한국공업화학회 1999 공업화학 Vol.10 No.4

상분리 방법으로 비대칭 폴리에테르이미드막을 제조하였고, 수산화나트륨 수용액으로 막의 표면층을 개질 했을 때의 몰폴로지 변화를 반응기간과 반응용액 농도에 대하여 살려보았다. 표면층 몰폴로지는 개질 용액의 농도가 증가함에 따라 치밀한 구조에서 둥근 입자상의 형태로 변화되었고, 개질 시간이 증가될수록 치밀 영역이 증가되었다. 그러나 반응 농도가 아주 높거나 장시간 개질을 하면 비대칭 폴리에테르이미드막의 표면에서 치밀 구조층이 없어지는 결과를 나타냈다. 결과적으로, 표면의 몰폴로지는 개질 용액의 농도와 시간에 따라 크게 좌우됨을 알 수 있었다. 이러한 결과는 폴리에테르이미드가 수산화나트륨에 의해서 폴리아믹산으로 가수분해되면서 나타나는 현상으로 추측되었다. Asymmetric polyetherimide membrane were prepared by phase inversion method, and the effects of NaOH concentration and reaction time on the morphology change of the polyetherimide membranes were studied. The morphology of skin layers varied from dense structure to sphere structure with increasing concentration of modification solution. The thickness of dense layer increased with increasing reaction time. However, when either the concentration of modifying solution was very high or the reaction time was very long, the dense layers of the asymmetric membrane were disappeared. From these results, it was found that the surface morphology of the asymmetric polyetherimide membranes depended strongly on the modification conditions such as concentration of modification solution and reaction time. These results might be explained by the hydrolysis reaction of polyetherimide into polyamic acid by the NaOH solution.

노인의 범죄패해특성에 관한 연구

김상균,Kim, Sang-Kyun 한국경호경비학회 2000 시큐리티연구 Vol.- No.3

The purpose of thesis is to examine the two aspects of realities and fear of criminal victimization in the old. It also intends to provide useful date for criminal victimization prevention strategies and looks for alternatives promoting social welfare of the old in our society. For this, some important theories about criminal victimization and compensating of crime victims are reviewed as theoretical backgrounds. In addition to theoretical reviews, to identify realities of criminal victimization and fear of crime among the old, empirical survey was conducted using questionnaires about 200 respondents of 60 years old in Taegu.