복시환자의 임상양상

김민석,최진,김정훈,김재석,이주화,Min Seok Kim,Jin Choi,Jung Hoon Kim,Jae Suk Kim,Joo Hwa Lee 대한안과학회 2013 대한안과학회지 Vol.54 No.11

Purpose: To evaluate the clinical features, causes and outcomes of patients with diplopia. Methods: All patients presenting with diplopia from October 2010 to March 2012 and followed up for more than 3 months were retrospectively investigated. Results: During the study period, 59 patients with diplopia were identified. There were 42 males and 17 females with an average age of 50 years. Binocular diplopia accounted for 54 cases (92%) and 5 cases (8%) had monocular diplopia. Cranial nerve palsies were the most common cause of binocular diplopia (28 cases, 52%). Within the cranial nerve palsies group, 14 cases (50%) were accompanied by hypertension or diabetes mellitus. Binocular diplopia spontaneously resolved in 35 cases (65%) by 3 months rising to 41 cases (76%) by 7 months. Thirteen (93%) out of 14 cases of cranial nerve palsies with hypertension or diabetes resolved spontaneously by 3 months. Conclusions: Binocular diplopia was caused most commonly by cranial nerve palsy and resolved after 3 months in 65% of patients. A spontaneous recovery from diplopia was observed after 3 months in 93% of patients with cranial nerve palsies and microvascular disease such as hypertension or diabetes. Therefore, the initial observation without additional treatment would be sufficient in these patients. J Korean Ophthalmol Soc 2013;54(11):1772-1777

열처리 및 단조조건에 따른 알루미늄 6056 소재의 특성변화 및 자동차의 피스톤 블록 설계

김민석,정병덕,박효영,최정묵,김정민,박준식,Kim, Min Seok,Jung, Hyung Duck,Park, Hyo young,Choi, Jeong Mook,Kim, Jeong Min,Park, Joon Sik 한국재료학회 2015 한국재료학회지 Vol.25 No.10

The mechanical properties and microstructures of Aluminum 6056 alloys were investigated for their use in the fabrication of a piton block. The EN-AW6056 alloys exhibited a tensile strength of 375 MPa for a solution treatment temperature of $550^{\circ}C$ for 2 h followed by an aging treatment at $190^{\circ}C$ for 4 h. The microstructures of the heat treated specimen showed that the $Mg_2Si$ phase with a size of 3~5 um was dispersed throughout the aluminum matrix when the heat treatment was done. Moreover, in order to identify the forgeability of the specimen, upsetting tests were done. For up to 80 % of the upsetting ratio, the specimen maintained its original shape, and at above 80 % of the upsetting ratio, the specimen underwent crack development. The specimen was successfully forged without any defects with the examined material conditions. The material conditions together with the forging conditions are discussed in terms of the microstructures and mechanical properties.

2.3 GHz 대역에서 단일 Half-LO 주파수를 이용한 Double-Conversion Down Mixer 설계

김민석,문주영,윤상원,Kim Min-Seok,Moon Ju-Young,Yun Sang-Won 한국전자파학회 2006 한국전자파학회논문지 Vol.17 No.8

본 논문에서는 Half-LO 주파수를 이용하는 새로운 방식의 double-conversion down mixer를 2.3 GHz 대역에서 설계하였다. 제안된 mixer에서는 Half-LO 주파수를 2개의 HEMT에 인가하여 두 HEMT에서의 변환 방식을 gate type과 resistive type으로 다르게 함으로서 IF 주파수를 얻게 된다. 기존의 sub-harmonic mixers와 같이 Half-LO 주파수를 사용하지만 제안된 mixer는 Half-LO의 second harmonic 성분을 이용하지 않고 Half-LO의 기본 주파수를 이용하여 주파수 변환을 하고 두 번째 HEMT에서 Resistive mixer type으로 IF 신호를 얻기 때문에 기존의 능동 mixer보다 향상된 선형성을 얻을 수 있다. 2.3 GHz 대역에서 설계 제작된 mixer는 Half-LO 전력 10 dBm을 이용하여 5dB의 변환 손실과 16.25dBm의 IIP3 특성을 얻을 수 있었다. In this paper, we designed the double conversion down mixer by using Half-LO frequency in 2.3 GHz band. The IF frequency is obtained by supplying two LO frequencies to HEMT in both gate type and resistive type. The proposed mixer uses Half-LO frequency the same way as conventional sub-harmonic mixers. However the proposed one uses fundamental component of Half-LO frequency in first stage instead of using second harmonic components of Half-LO frequency, and the IF frequency is obtained by resistive type mixer in second stage, thereby the proposed mixer can improve linearity in comparison with conventional active mixer. We can verify that the proposed mixer has an conversion loss of 5dBm and IIP3 of 16.25dBm by using 10 dBm Power.

영상처리 기법을 이용한 샥-하트만 파면 센서의 측정범위 확장에 대한 연구

김민석,김지연,엄태경,윤성기,이준호,Kim, Min-Seok,Kim, Ji-Yeon,Uhm, Tae-Kyung,Youn, Sung-Kie,Lee, Jun-Ho 한국광학회 2007 한국광학회지 Vol.18 No.6

샥-하트만 센서는 렌즐릿 배열을 이용하여 파면의 국부적인 기지를 계산하고 이로부터 파면의 왜곡된 정도를 측정하는 파면측정 센서이다. 일반적으로 하나의 점영상에 대한 중심점을 추출하여 기준 점영상의 중심점에 대한 상대적 이동량을 통해 파면의 국부 기울기를 계산, 전체 파면을 복원하는 원리이다. 따라서 하나의 점영상에 대한 정확한 중심점의 추출을 위하여 해당하는 하부개구 내에 점영상이 존재하여야 한다. 하지만 큰 기울기의 파면이 샥-하트만 센서에 입사하게 되면 측정범위를 벗어나게 되어 일반적인 방법으로는 파면의 국부적인 기울기를 계산할 수 없게 되는 문제점이 있다. 이를 해결하기 위해 특정 측정시스템에만 국한된 알고리즘이 아닌 모든 파면에 대해 측정 가능하면서도 추가적인 장비 없이 일반적인 샥-하트만 파면 센서가 지니고 있는 측정범위의 한계를 극복할 수 있는 알고리즘이 필요하다. 본 연구에서는 영상처리 기법을 이용하여 각 점영상에 대한 유동적인 탐색영역을 설정하고 이러한 탐색영역 내에서 중심점을 추출하는 방법을 제안하였다. 또 점영상 대응법을 적용하여 측정 점영상과 기준 점영상을 일대일 대응시킴으로써 전체 측정파면을 복원할 수 있는 알고리즘을 제안함으로써 측정범위에 제한 없이 파면왜곡을 측정할 수 있는 측정방법을 제시하였다. 이렇게 제안된 알고리즘을 샥-하트만 파면 센서 시스템을 이용한 초점벗어남 측정실험을 통하여 검증하였다. The Shack-Hartmann wavefront sensor is composed of a lenslet array generating the spot images from which local slope is calculated and overall wavefront is measured. Generally the principle of wavefront reconstruction is that the spot centroid of each lenslet array is calculated from pixel intensity values in its subaperture, and then overall wavefront is reconstructed by the local slope of the wavefront obtained by deviations from reference positions. Hence the spot image of each lenslet array has to remain in its subaperture for exact measurement of the wavefront. However the spot of each lenslet array deviates from its subaperture area when a wavefront with large local slopes enters the Shack-Hartmann sensor. In this research, we propose a spot image searching method that finds the area of each measured spot image flexibly and determines the centroid of each spot in its area Also the algorithms that match these centroids to their reference points unequivocally, even if some of them are situated off the allocated subaperture, are proposed. Finally we verify the proposed algorithm with the test of a defocus measurement through experimental setup for the Shack-Hartmann wavefront sensor. It has been shown that the proposed algorithm can expand the dynamic range without additional devices.

상호운용을 지원하는 코바 기반 공간 데이터 제공자의 설계 및 구현

김민석,안경환,홍봉희,Kim, Min-Seok,An, Kyoung-Hwan,Hong, Bong-Hee 한국공간정보학회 1999 개방형지리정보시스템학회 논문지 = Journal of the Korea Open Geogr Vol.1 No.2

CORBA와 같은 분산 컴퓨팅 환경에서 이종의 시스템 및 데이타베이스들의 통합을 위해 기존에는 포장자(wrapper)를 사용하였다. 이러한 여러 분야에 적용되는 포장자들 중에는 클라이언트에게 공통의 인터페이스를 제공하는 공간 데이타 제공자가 있다. 기존에는 공간 데이타 제공자를 데이타 소스별로 작성해야 하기 때문에 중복 구현과 구현 후의 변경 확장에 대한 문제가 있다. 이 논문에서는 공간 데이타 세공자의 재사용과 확장성을 위해 독립 포장자 객체와 종속 포장자 객체의 두개의 층으로 이루어진 새로운 구조를 제시한다. 종속 포장자 객체는 각 데이타소스에 대한 공간 데이타 작성시에 새로이 작성되야 하는 객체이고, 독립포장자 객체는 재사용될 수 있는 객체를 말한다. 또한 이 논문에서는 미들웨어에서 질의 처리 결과 유지 방법에 따른 구현 방법론을 제시한다. 질의 결과 유지 방법에는 질의 결과를 데이타로 유지하는 방법과 CORBA 객체로 변환하여 유지하는 방법으로 나뉘어진다. 각 방법에 대한 성능 평가 결과 CORBA 객체를 생성하는 방법의 비용이 상당히 높은 것을 알 수 있다. In distributed computing platforms like CORBA, wrappers are used to integrate heterogeneous systems or databases. A spatial data provider is one of the wrappers because it provides clients with uniform access interfaces to diverse data sources. The individual implementation of spatial data providers for each of different data sources is not efficient because of redundant coding of the wrapper modules. This paper presents a new architecture of the spatial data provider which consists of two layered objects : independent wrapper components and dependent wrapper components. Independent wrapper components would be reused for implementing a new data provider for a new data source, which dependent wrapper components should be newly coded for every data source. This paper furthermore discussed the issues of implementing the representation of query results in the middleware. There are two methods of keeping query results in the middleware. One is to keep query results as non-CORBA objects and the other is to transform query results into CORBA objects. The evaluation of the above two methods shows that the cost of making CORBA objects is very expensive.

BTMSM/$O_2$ 고유량으로 증착된 low-k SiOCH 박막의 전기적인 특성

김민석,황창수,김홍배,Kim, Min-Seok,Hwang, Chang-Su,Kim, Hong-Bae 한국반도체디스플레이기술학회 2008 반도체디스플레이기술학회지 Vol.7 No.1

We studied the electrical characteristics of low-k SiOCR interlayer dielectric(ILD) films fabricated by plasma enhanced chemical vapor deposition (PECVD). The precursor bis-trimethylsilylmethane (BTMSM) was introduced into the reaction chamber with the various flow rates. The absorption intensities of Si-O-$CH_x$, bonding group and Si-$CH_x$, bonding group changed synchronously for the variation of precursor flow rate, but the intensity of Si-O-Si(C) responded asynchronously with the $CH_x$, combined bonds. The SiOCH films revealed ultra low dielectric constant around 2.1(1) and reduced further below 2.0 by heat treatments.

Greedy Kernel PCA를 이용한 화자식별

김민석,양일호,유하진,Kim, Min-Seok,Yang, Il-Ho,Yu, Ha-Jin 대한음성학회 2008 말소리 Vol.66 No.-

In this research, we propose a speaker identification system using a kernel method which is expected to model the non-linearity of speech features well. We have been using principal component analysis (PCA) successfully, and extended to kernel PCA, which is used for many pattern recognition tasks such as face recognition. However, we cannot use kernel PCA for speaker identification directly because the storage required for the kernel matrix grows quadratically, and the computational cost grows linearly (computing eigenvector of $l{\times}l$ matrix) with the number of training vectors I. Therefore, we use greedy kernel PCA which can approximate kernel PCA with small representation error. In the experiments, we compare the accuracy of the greedy kernel PCA with the baseline Gaussian mixture models using MFCCs and PCA. As the results with limited enrollment data show, the greedy kernel PCA outperforms conventional methods.

당뇨망막병증에서 나비라스 레이저 시스템과 기존 범망막광응고술의 소요시간과 통증 비교

김민석,이성우,김재석,Min Seok Kim,Seong Woo Lee,Jae Suk Kim 대한안과학회 2014 대한안과학회지 Vol.55 No.8

Purpose: To compare the pain scale and time necessary for panretinal photocoagulation (PRP) between Navilas<sup><font size=`2`>Ⓡ</font> (OD-OS, Teltow, Germany) and conventional laser in diabetic retinopathy. Methods: Fifteen patients who required PRP for diabetic retinopathy were enrolled in the present study. PRP was performed using Navilas<sup><font size=`2`>Ⓡ</font> (5 x 5 array patterned system) in the superior, nasal and inferior areas, and using conventional laser at the temporal area 1 week later. Total time of laser application and number of laser shots were counted for calculating required time per 100 spots of each laser system. Immediately after the laser photocoagulation, patients were asked to quantify their pain on a visual analog pain scale (0 = no pain; 10 = worst pain). Results: PRP using Navilas<sup><font size=`2`>Ⓡ</font> required shorter time per 100 laser spots (27.7 sec vs. 102.0 sec, <em>p</em> < 0.001) and subjects had lower treatment-related pain than with the conventional laser system (3.3 vs. 6.9,<em> p</em> < 0.001). Conclusions: PRP using Navilas<sup><font size=`2`>Ⓡ</font> can be considered as an efficient method for improving patient and operator's comfort with faster laser application and lower treatment-related pain. J Korean Ophthalmol Soc 2014;55(8):1150-1154

Functional Independence Measure를 이용한 뇌졸중(腦卒中) 환자의 임상적 관찰

김민석,정승현,신길조,이원철,Kim, Min-Seok,Jung, Seung-Hyun,Shin, Gil-Cho,Lee, Won-Chul 대한한방내과학회 1998 大韓韓方內科學會誌 Vol.19 No.1

BACKGROUND The purpose of this study was to investigate disability of the patients after stroke, clinical applicability and usefulness of the FIM in evaluating the functional abilities and to assess the characteristics of the patients after stroke. And this study examined difference by predictive factors on the treatment outcome. METHOD The study was composed of 31 stroke patients who were within 1 week after stroke and had been treated in hospital more than 4 weeks. Improving rate was measured by using the Functional Independence Measure(FIM), and the correlation was analyzed between Motor FIM and Cognitive FIM. We analyzed significant meaning statistically in the mean value of FIM. RESULT 1. There was no significant meaning statistically in the mean value of FIM that was between both at admission and after 2 weeks. But there was proportional correlation between both at admission and after 4 weeks, and significant meaning statistically. 2. There was proportional correlation between both FIM and Motor FIM, and significant meaning statistically. But there was no significant meaning statistically between both FIM and Cognitive FIM. 3. There was no significant meaning statistically between both FIM and sex, age, side of weakness, stroke subtype, hypertension, hypercholesterolemia, diabetes mellitus, heart disease, starting point of rehabilitation therapy and past history of cerebral vascular accident. While dysarthria affected functional recovery in stroke patients, and significant meaning statistically. CONCLUSION 1. FIM appeared to be a valid and reliable method to measure the functional abilities of the patients after stroke. 2. Only one thing between Motor FIM and score didn't influence FIM score. 3. Dysarthria affected functional recovery in stroke patients, and it is the statistically significant factor.

유완소(劉完素)의 중풍론(中風論)에 관(關)한 고찰(考察)

김민석,정승현,신길조,이원철,Kim, Min-Seok,Jung, Seung-Hyun,Shin, Gil-Cho,Lee, Won-Chul 대한한방내과학회 1997 大韓韓方內科學會誌 Vol.18 No.1

In this study, the purpose was to consider the conception, the causes, the pathology, the treatment and the prescription of 'Zhong Feng(中風)' through Liu Wan-Su's works. The results are obtained as fallows. First, Liu Wan-Su regarded Zhong Feng(中風) as 'Feng Re(風熱)'. He thought the causes and the pathology of Zhong Feng(中風) that pathologically fever was due to excess of feelings and 'Heart-fire(心火)', was due to intemperate living, so he thought the leading causes of Zhong Feng(中風) were Feng Re(風熱) and Heart-fire(心火) and emphasized the internal causes of Zhong Feng(中風). But he excluded absolutely external causes. He also insisted that Feng Re(風熱) was cause in a fat and a thin person. Second, according to symptom of the limbs and 'Jiu Qiao(九竅)', he classified Zhong Feng(中風) into 'Zhong Fu(中腑)' and 'Zhong Zang(中臟)'. And in the treatment of Zhong Feng(中風), the three principle was set up that 'Sweating .method(發表法)' in the case of Zhong Fu(中腑), 'Passing method(通滯法)' in Zhong Zang(中臟) and 'Nutrient method(養筋法)', in case that both symptom would not revealed. And in the prescription of Zhong Feng(中風), he presented 'Xumingtang(續命湯)', 'Sanhuatang(三化湯)' and 'Daqinfantang(大秦?湯)' to them each.