근위축성 측삭경화증 환자 1년 후 추적 조사

김현식,송봉근,박만용,임나라,김성하,김성철,Kim, Hyun-Sik,Song, Bong-Kuen,Park, Man-Yong,Lim, Na-Ra,Kim, Sung-Ha,Kim, Sung-Chul 대한약침학회 2010 Journal of pharmacopuncture Vol.13 No.1

Objectives : This study was to investigate the effects of Oriental medical treatment on ALS. Methods : We investigated 12 ALS patients which were admitted to Gwang-Ju O.M.hospital for 3 months and follow-up at 8 months after discharge. All patients were treated by SAAM-acupuncture, herb medication, Bee venom Pharmacopuncture therapy, Needle-embedding therapy, etc and after discharge self-therapy at home. We evaluated patients using the Amyotrophic lateral sclerosis Functional Rating Scale-Revised(ALSFRS-R), Medical Research Council (MRC) Scale. Results : After 1 month, mean ALSFRS-R score of patients was $29.08{\pm}7.99$, 2 months $28.70{\pm}7.17$, 3 months $28.16{\pm}8.23$, 1 year $21.33{\pm}9.93$ and mean MRC Scale of patients was $25.34{\pm}8.45$, 2 months $25.34{\pm}8.45$, 3months $21.56{\pm}9.20$. But in both cases, the variation was not statistically significant. Conclusions : We think that the results of this case be a pilot study that proves the effect of Oriental Medical treatment on ALS.

Multi Channel LED 조명 Module 구동에서 최대 효율을 위한 최대 Channel 전압 감지회로

김현식,김기원,김기훈,김유신,송상빈,Kim, Hyun-Sik,Kim, Ki-Woon,Kim, Gi-Hoon,Kim, Yu-Sin,Song, Sang-Bin 한국전기전자재료학회 2012 전기전자재료학회논문지 Vol.25 No.11

LED is divided to multichannel in order not to exceed a certain voltage in aspects of electric standard. However, it's not possible to know in accordance with what channel SMPS controls the constant voltage and current. In order to solve this problem, it needs to detect the maximum LED String voltage which is applied to LED control circuit, and it is possible to minimize the voltage drop when a difference of LED string voltage occurs by each channel if LED is controlled by the maximum LED string voltage detected. In addition, it is also possible to maximize the efficiency of LED if change LED voltage by detecting the maximum voltage. Feasibility of this claim was verified through implementation of the circuit.

가변 시상수를 이용한 자동 노출제어 시스템

김현식,이성목,장원우,하주영,김주현,강봉순,이기동,Kim, Hyun-Sik,Lee, Sung-Mok,Jang, Won-Woo,Ha, Joo-Young,Kim, Joo-Hyun,Kang, Bong-Soon,Lee, Gi-Dong 한국정보통신학회 2007 한국정보통신학회논문지 Vol.11 No.2

In order to obtain a fine picture, a camera has many convenient functions. Its representative functions are Auto Focus(AF), Auto White Balance(AWB) and Auto Exposure(AE). In this paper, we present the new algorithm of Auto Exposure control system, one of its useful functions The proposed algorithm of Auto Exposure control system is based on IIR Filter with Variable Time Constant. First, in order to establish the standards of exposure control, we compare change of the picture luminance with luminance of an object in the Zone system. Second, we make an ideal characteristic graph of luminance by using the results. Finally, we can find the value of the right exposure by comparing an ideal characteristic graph of the luminance with the value of the current expose of a scene. We can find an appropriate exposure as comparing the ideal characteristic graph of the luminance with current exposure of a scene. In order to find a suitable exposure state, we make use of IIR Filter instead of a conventional method using micro-controller. In this paper, the proposed system has therefore simple structure, we use it for compact image sensor module used in the handheld device. 사진을 찍을 때 카메라는 보기 좋은 사진을 얻을 수 있도록 많은 기능을 제공하고 있다. 대표적인 기능으로 자동 초점거리 조정(Auto Focus), 자동 색온도 보정(Auto White Balance), 자동 노출 조정(Auto Exposure)이 있다. 본 논문에서는 편리한 기능들 중 하나로서 새로운 자동 노출제어 시스템을 제안한다. 본 논문에서 제안하는 자동 노출제어 시스템은 가변 시상수(Variable Time Constant)를 가지는 IIR Filter를 이용한다. 먼저 노출제어의 기준을 정하기 위해서 사진에서 밝기변화와 Zone System에서 보여주는 사물의 휘도정보를 비교하여 이상적인 휘도변화 특성 그래프를 얻는다. 얻어진 이상적인 휘도 변화 그래프와 현재의 노출설정을 비교하여 적정 노출의 설정을 찾는다. 제안하는 자동 노출제어 시스템은 적정 노출을 얻을 수 있는 설정으로 조정하기 위해 기존의 마이크로 콘트롤러 등을 이용하여 구현하는 방법과 달리 IIR Filter를 사용하므로 간단한 구성을 가지며 콤팩트 이미지 센서모듈(ISM)를 구성하기 위하여 사용할 수 있다.

퍼지 슬라이딩 모드 제어기 및 신경망 보간기를 이용한 Underwater Flight Vehicle의 심도 제어

김현식,박진현,최영규,Kim, Hyun-Sik,Park, Jin-Hyun,Choi, Young-Kiu 대한전기학회 2001 전기학회논문지 D Vol.52 No.3

In Underwater Flight Vehicle depth control system, the followings must be required. First, it needs robust performance which can get over modeling error, parameter variation and disturbance. Second, it needs accurate performance which have small overshoot phenomenon and steady state error to avoid colliding with ground surface or obstacles. Third, it needs continuous control input to reduce the acoustic noise and propulsion energy consumption. Finally, it needs interpolation method which can sole the speed dependency problem of controller parameters. To solve these problems, we propose a depth control method using Fuzzy Sliding Mode Controller with feedforward control-plane bias term and Neural Network Interpolator. Simulation results show the proposed method has robust and accurate control performance by the continuous control input and has no speed dependency problem.

머신러닝 알고리즘을 사용한 웨어러블 스마트 에어백에 관한 연구

김현식,백원철,백운경,Kim, Hyun Sik,Baek, Won Cheol,Baek, Woon Kyung 한국안전학회 2020 한국안전학회지 Vol.35 No.2

Bikers can be subjected to injuries from unexpected accidents even if they wear basic helmets. A properly designed airbag can efficiently protect the critical areas of the human body. This study introduces a wearable smart airbag system using machine learning techniques to protect human neck and shoulders. When a bicycle accident happens, a microprocessor analyzes the biker's motion data to recognize if it is a critical accident by comparing with accident classification models. These models are trained by a variety of possible accidents through machine learning techniques, like k-means and SVM methods. When the microprocessor decides it is a critical accident, it issues an actuation signal for the gas inflater to inflate the airbag. A protype of the wearable smart airbag with the machine learning techniques is developed and its performance is tested using a human dummy mounted on a moving cart.

수량화II류를 이용한 산림휴양기능의 평가

김현식,Kim, Hyun-Sik 한국산림과학회 2008 한국산림과학회지 Vol.97 No.4

본 연구는 자연휴양림 내에서 휴양지구를 설정하기 위한 방법을 모색하기 위하여 산림휴양기능의 평가를 시도하였다. 청옥산 자연휴양림을 연구대상지로 선정하고, 표준지 173개 소반을 추출하여 수량화II류를 이용하여 분석하였다. 이때 외적기준은 산림휴양 효용의 정도를 전문가로부터 부여받았고, 설명변수는 기존의 연구결과와 대상지의 산림휴양자원을 고려하여 임상, 임령, 경사, 수변, 도로, 시설의 6인자를 선정하였다. 그 결과, 절대판별적중률은 제 1 2상관비 축에서 각각 82%, 75%로서 예측 가능한 판별 정도(精度)를 얻었다. 요인으로서는 도로와 경사가 산림휴양기능의 잠재력에 큰 영향을 미치고 있으며, 카테고리에 있어서는 도로가 있는 것이, 경사는 낮을수록 산림휴양기능을 높이는 방향으로 작용하는 것을 알 수 있었다. 또한, 청옥산 자연휴양림의 소반별 산림휴양기능의 잠재력을 평가하기 위하여 표준지에서의 예측식을 사용하여 산림휴양효용의 정도를 나타내는 종합점수를 구한 다음, 판별구분점에 의하여 높다(H), 보통(M), 낮다(L)로 3구분하였으며, GIS를 이용하여 분포를 나타내는 평가도를 작성하였다. 수량화라는 형식을 매개로 하여 산림휴양의 효용의 정도에 관한 현실의 직관적 경험적 종합판단을 평가인자와 카테고리가 개입된 분석적 판단으로 변환하고 있는 점에 본 연구의 의의가 있다. This study has intended to evaluate the forest recreation functions to seek methods to designate the recreational areas inside a recreation forest. This study has Mt. Chung-ok in Korea as a study area to which Quantification method II as a valuation measure was applied. This study also has chosen a degree of recreational utility as an external criterion and six factors including Forest type, Forest age, Slope, Riparian area, Road, and Facility for the 173 stands in this area. As a result, absolute discriminated success rate was obtained, so that the first and second estimated correlation ratios were 82% and 74%, respectively. Road and Slope had great influences on the potential power of recreational functions. In the category, recreational function was more influenced by the existence of road and the lower degree of slope. Also, this study has drawn an evaluation map, which displayed the potential power of recreational functions by classifying three discrimination points such as H(High), M(Medium), and L(Low) through calculating the degree of recreational utility of the recreation forest for the stands by applying an estimation formula of recreational function in the stands. This study seems to be worthwhile in terms of actual, experimental, and intuitive interpretation for the degree of recreational utility calculated by using Quantification method theory.

열차 내 무배선통신시스템 구축을 위한 통신연결장치 개발

김현식,박수훈,강석근,Kim, Hyun Sik,Park, Soo Hoon,Kang, Seog Geun 한국정보통신학회 2015 한국정보통신학회논문지 Vol.19 No.4

본 논문은 열차 내에 산재한 도체 선로를 활용하여 무배선통신시스템 구축할 수 있는 통신연결장치의 설계 방법을 제시한다. 또한 여기서는 기존 선로에 직접 연결되는 전도성 연결장치와 전자기 유도현상을 이용하는 유도성 연결장치를 개발한다. 개발된 통신연결장치를 전력선에 적용하여 데이터 통신 실험한 결과, 목표 성능인 200 m 거리에서 20 Mbps급 이상의 무배선통신시스템의 구축을 실현할 수 있음을 확인하였다. 또한 내환경 시험 결과 개발된 통신연결장치는 열차의 내외부 발생될 수 있는 극심한 환경 변화에서도 안정적으로 동작하는 것으로 측정되었다. 따라서 개발된 장치는 현재 운행되고 있는 열차의 전도성 매체를 활용한 통신네트워크 구축에 유용할 것으로 판단된다. In this paper, a design of communication joint tools to implement a legacy-line communication (LLC) system, which exploits various conductive lines in a train, is presented. We develop two kinds of joint tools; one is a conductive joint tool (CJT) that is connected directly to the conventional lines and the other is the inductive joint tool (IJT) which connects the conventional lines indirectly using electromagnetic induction. As a result, the practical experiment of data communication confirms that an LLC system with the developed joint tools has a transmission rate more than 20 Mbps in the distance of 200 m away. In addition, an environmental durability test shows that the joint tools operate stably in an extreme environmenal variation. It is, therefore, considered that the developed joint tools are very useful to implement a communication network in the train working currently.

선박 내 통신네트워크 구축을 위한 전력선 기반 무배선통신시스템

김현식,강석근,Kim, Hyun-Sik,Kang, Seog Geun 한국정보통신학회 2015 한국정보통신학회논문지 Vol.19 No.8

본 논문은 전력선 기반 무배선통신시스템을 이용하여 선박에 통신네트워크를 구축하는 방안을 제시한다. 이를 위하여 전력선과 데이터통신 기기의 연결을 위한 유도성 결합장치와 복합통신장치를 개발한다. 실제 운항되는 선박을 대상으로 시험한 결과, 구현된 무배선통신시스템은 최장 200 m 거리에서 25.8 Mbps 이상의 전송속도를 제공하고, 통신 성공률은 100%인 것으로 측정되었다. 따라서 제시된 시스템은 전송채널의 추가 설치 없이도 선박에 통신네트워크를 구축할 수 있는 유용한 대안인 것으로 판단된다. 또한 설치가 용이하고 데이터통신을 위한 다양한 인터페이스를 지원하므로 미래 디지털 선박에 실시간 모니터링 시스템을 도입하는 경우 매우 효과적일 것으로 기대된다. In this paper, a method of implementing a communication network in ship, which exploits a powerline-based legacy-line communication system (LLC), is presented. We develop an inductive coupling unit and a multi-interface device to connect a data communication terminal to the powerline. As a result of operation tests for the ship under working, the implemented LLC shows a transmission rate of at least 25.8 Mbps in the distance of 200 m away with 100% success rate. Thus, the system can be a useful alternative to implement a communication network in ship without additional channels. Being easy to be implemented and supporting various interfaces for data communication, the presented system will be very effective when a real-time monitoring system is launched in future digital ship.

송전선용 비접촉식 커플러의 설계와 적용연구

김현식,이동철,김민호,이진,오영우,민병훈,Kim, Hyun-Sik,Lee, Dong-Chul,Kim, Min-Ho,Lee, Gean,Oh, Young-Woo,Min, Byung-Hoon 한국전기전자재료학회 2010 전기전자재료학회논문지 Vol.23 No.3

An inductive coupler, which feeds communication to the electric power transmission line, is required to establish Power Line Communication(PLC). The electro-magnetic property of magnetic core and design technology for coupler are very important to manufacture an inductive coupler for power transmission line. The magnetic core with superior electro-magnetic property was manufactured by using nanocrystalline alloy and an inductive coupler, which can operate at the maximum 2,000 A current, was designed and manufactured by establishment of current saturation, signal out winding, and electromagnetic simulation in this study. Communication speed of 14 Mbps in 600 meter communication distance of the real electric power transmission line was obtained by using the inductive coupler and application possibility of the inductive coupler for the electric power transmission line was certified.

CoNbZr / Cu / CoNbZr 다층막의 습식 식각에 관한 연구

김현식,민복기,송재성,이영생,오영우 ( Hyun Sik Kim,Bok Ki Min,Jae Sung Song,Young Seang Lee,young Woo Oh ) 한국전기전자재료학회 1997 한국전기전자재료학회 춘계학술대회논문집 Vol.1997 No.0