측정 또는 동력학적 잡음이 개입된 Lorenz 모형에서 시계열의 길이에 따른 매립환경변수 결정

이상훈 인제대학교기초과학연구소 1999 자연과학 Vol.3 No.-

최근 발전되고 있는 표준 시계열 분석 프로그램인 TISEAN을 이용하여 측정 또는 동력학적 잡음이 개입된 Lorenz모형에서 얻어진 혼돈 시계열의 길이에 따른 매립환경변수의 변화를 조사하였다. 잡음이 없는 경우 지연시간과 매립차원은 시계열의 길이가 짧을 경우 변화의 폭이 크나 길이가 8K(8192)개 이상이 되면 일정한 값을 유지한다. 매개변수를 매 순간 변화시키는 동력학적 잡음은 잡음이 개입되는 방향 성분의 시계열의 매립차원을 시계열의 길이가 충분히 길 때 2차원정도 상승시켰으며, 측정 잡음은 시계열의 길이가 늘어남에 따라 매립차원을 계속 증가시켰다. 본 결과는 여러 유형의 잡음들이 항상 개입되는 생체시계열의 매립환경 변수를 결정하는 기준 설정에 유용하다. Under the change of length of chaotic time series acquired from Lorenz model with measurement or dynamical noises involved, variations of embedding parameters were investigated using TISEAN that has recently been developed. Delay time and embedding dimension became constant when length of time series without noise exceeds 8K(8192), though it has large variance for short time series. Measurement noise reflecting the effect of changes in parameter in crease the embedding dimension of time series of noise-intervened component more than 2 dimensions. Measurement noise tends to continually increase embedding dimensions as the length of time series becomes larger. Those results may become useful in fixing criterion for determining the embedding parameters of life signals with various types of noises intervened.

당뇨환자의 말초혈관 혈류의 평균 진폭-스펙트럼-밀도 분석에 의한 신경증 및 갑상선 기능 조사

이상훈,남상희,유영종 인제대학교기초과학연구소 1998 자연과학 Vol.2 No.-

수지배면부(finger dorsum surface)의 말초혈관으로부터 비침습적인 (noninvasive) 방법인 LDF (Laser Doppler Flowmetry)을 이용하여 혈류흐름을 측정하였다. 당뇨환자가 정상인에 비하여 말초혈관의 혈류흐름이 손상되었음 1.25Hz 이하의 저주파영역에서의 FFT 분석을 이용한 평균 진폭-스펙트럼-밀도 (Amplitude Spectral Densities)를 통해서 조사하였다. 당뇨환자를 신경장애 음성반응 환자와 양성반응 환자, 갑상선기능항진 환자, 갑상선기능저하 환자로 구분하여, 말초혈관 혈류흐름에 대한 신경장애 및 갑상선기능의 영향을 조사하였다. 신경장애 양성 환자가 음성 환자보다 말초혈관 혈류흐름에 손상을 보이는 초저주파수 영역(0.0073-0.0513Hz)이 혈류 순환을 조절하는 신경계와 관련된 주파수 대임을 확인하였다. 또한 갑상선 기능저하 환자가 기능항진 환자보다 혈류흐름에 이상이 있음을 확인하였다. In the noninvasive measurement using LDF(Laser Doppler Flowmetry), time series of the blood flow were peripheral blood vessels of the finger dorsum surface. From the FFT analysis of frequency range lower than 1.25Hz, mean of amplitude spectral densities shows that the blood flow of diabetes was more impaired than the normal. We examined the effect of neuropathy and thyroid function on the blood flow in the peripheral blood vessels among diabetes with the following symptoms; neuropathy positive or negative, hypothyroidism or hyperthyroidism. The result that neuropathy positive undergo more impairment in blood flow than neuropathy negative in the very low frequency range implied that the very low frequency range (0.0073-0.0513Hz) is relevant to the nervous function of the circulating system of blood. We also confirmed that the blood flow of the hypothyroidism is more impaired than that of the hyperthyroidism.

건설현장 불법체류 외국인근로자 고용에 대한 내국인근로자 의식에 관한 연구

이상민,안성훈 대구대학교 산업기술연구소 2013 産業技術硏究 Vol.24 No.1

Foreign labors are increasing in Korean construction site due to lacks of domestic labors. The consciousness of domestic labors influences on the organization management in construction projects. So, the purpose of this study is to analyze the consciousness of the domestic labors are conscious that employment of illegal alien foreign labors are faithful and useful for the easy works in construction site. However, it is also revealed that the difficulty of employment, the short stay period, and little Korean ability are problems of illegal alien foreign labors to overcome for the improvement of organization management.

평면 구성 및 공간 분석을 위한 프로그램 개발

정상규,박우장,이요희,이훈 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.1

This paper aims at developing a program for the composition of plan and the analysis of space. This program is able to draw plans more easily and quickly, and to seek a proper design solution by analyzing the topology of space based on Space Syntax(Hillier & Hanson, 1984). The program includes the Algorithms united some theories such as Shape Grammar(Stiny & Mitchell, 1980). Dimensionless Representation, Space Syntax and so on. Therefore we exhibit developing tools for modifying, editing and analyzing architectural plans.

하악골에 발생된 Low grade 골육종:증례보고

조현이,정종철,김호성,최재욱,성대경,서지훈,김성범,이계혁 大韓顎顔面成形再建外科學會 2000 Maxillofacial Plastic Reconstructive Surgery Vol.22 No.1

Osteosarcoma is a primary malignant tumor arising most often in the long bone, but rare in jaw bone. Especially osteogenic sarcoma of the mandible is a rare tumor, comprising less than 0.5% of all head and neck tumors. Osteosarcoma occurs cheifly in young persons, and presenting very survival rates. Histopathologically this tumor can be classified three types, osteoblastic, fibroblastic, chondroblastic and classified from low grade to high grade by anaplasia or mitosis of the tumor cells. Sometimes, the exact diagnosis of osteosarcoma is difficult especially in low grade osteosarcoma, even if clinical or radiographical findings suggest to osteosarcoma. So suspcious to malignant bone tumor in clinical or radiological findings, biopsy should be taked from deep portion and multiple area, and sharing the patient history and radiographs with pathologist will assist in the development of the diagnosis. We report a case of low grade osteosarcoma on the mandible initially difficulty in accurate diagnosis. The patient visited our hospital for routine dental treatment but radiographic findings displayed ill-defined radiolucency with osteoid formation on the mandible. Final diagnosis was difficulty in initial biopsy but subsequent biopsy taked from deep portion presented infiltrative growth and mitosis of the tumor cell in some area with small osteoid bone formation, so we could reach final diagnosis as low grade sarcoma. We treated this patient with bloc resection of the mandible and immediate reconstruction with iliac corticocancellous block.

최대 등척성 수축시 표면근전도에서 근 수축 개시점 결정을 위한 기법들의 신뢰도

정이정,조상현,이정훈,이상헌 한국전문물리치료학회 2003 한국전문물리치료학회지 Vol.10 No.1

The purpose of this study was to compare the relative accuracy of a range of computer-based analysis with respect to EMG onset determined visually by an experienced examiner. Ten healthy students (6 male, 4 female) were recruited and three times randomly selected trials of isometric contraction of wrist flexion and extension were evaluated using four technique. These methods were compared which varied in terms of EMG processing, threshold value and the number of samples for which the mean must exceed the defined threshold, and beyond 7% of maximum amplitude. To identify determination of onset time, ICCs(Intraclass Correlation Coefficients) was used and inter-rater and intra-rater reliability ranged good in visually derived onset values. The results of this study present that in wrist flexion and extension, the reliability of the inter and intra-examiner muscle contraction onset times through visual analysis showed beyond .971 with ICCs. The reliability of the muscle contraction onset time decision through visual reading, tested with computer analysis, showed a relationship of all the selected analysis methods with ICCs .859 and .871. The objective computer-based analysis comparing with visual reading at the same time is the effective and qualitative data analysis method, considering the specificity of each study method.

긍정 또는 부정 청각자극에 대한 뇌파시계열의 비선형분석

이운철,이상훈 인제대학교 1998 仁濟論叢 Vol.14 No.1

요약 긍정 또는 부정 청각자극에 대한 뇌 전도신호(EEG)의 변화를 측정한 스칼라시계열에 대해 평균상호정보량(AMI), FNN알고리듬을 이용하여 지연 시간, 매립차원을 결정하였다. 시간지연좌표를 이용해 벡터공간을 재구성하여 끌개의 비선형 지수인 상관차원과 리야푸노프지수 그리고 Mean Crossing을 계산하였다. 끌개의 공간구조와 비선형 지수의 시간적 변화정도가 청각자극 전후의 뇌파의 동력학적 변화를 설명하는 척도가 됨을 확인했다. 또한 뇌의 부위 별로 자극의 종류에 따라 리야푸노프지수 등 비선형 적인 량들이 변화하는 정도를 조사하여 뇌의 각 부위별 반응을 분류하였다. 그리고 부정 청각자극에 대한 반응이 우측두엽에서 크게 발생함을 보인 wavelet 분석 결과를 확인하였다. Using algorithms of average mutual information and false nearest neighbors, the delay time and embedding dimensions were determined for the scalar time series measuring the variation of electroencephalogram(EEG) subject to positive or negative auditory stimulus. After reconstructing vector space in terms of time-delayed coordinates, we calculate nonlinear parameters of attractor; correlation dimension, lyapunov exponent, mean crossing. Geometric structure of attractor and the time variation of nonlinear parameters become good measures to explain the dynamical change during auditory stimulation. By examining the rate of change in nonlinear parameters such as lyapunov exponent, the response of brain were classified up to the sections of brain and the types of stimulus. Our analysis confirms the result of wavelet analysis that the right temporal lobe strongly responds to the negative auditory stimulus.

프랙탈변환 방법에 의한 컬러 영상 압축에서의 최적 컬러축약률 및 범위 이동

명연수,이상훈,이형원,임철홍 인제대학교 1993 仁濟論叢 Vol.9 No.2

프랙탈변환을 이용하여 256가지 색을 가진 영상을 압축하는 모사 실험을 수행하였다. 영역의 크기, 컬러축약률,범위 이동치 변화에 따른 압축 영상의 평균 강도 차를 비교하여 최적 압축 조건을 조사하였다. By using the fractal transform we perform the simulations that compress the 256-color real world images. The optimal compression conditions are examined by comparing the compressed images resulting from the variations of the size of domain, ratio of color contraction and range-shift.

비보강 조적벽체 전단내력산정에 관한 연구

이봉근,이정한,이원호,오상훈,나정민 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.1(구조계)

In Korea, more than four hundred earthquakes with medium intensity centered on off-coastal and inland of Korea during the past 20 years and due to the great earthquakes which occurred recently in neighboring countries the importance of the future earthquake preparedness measures in Korea is highly recognized. More than 80 percents of residential buildings are constructed with unreinforced masonry structure, in Seoul. In general, unreinforced masonry structure don't have enough strength against the lateral force. And low rise buildings such as unreinforced masonry structure didn't adopted seismic design. So, a huge damage is expected when an earthquake occurs. It is that the major variables of shear strength are the aspect ratio, the vertical strength and the method of masonry. The objectives of this study are, 1) to find out the shear behavior of masonry wall and the variables affect the shear capacity of masonry wall such as aspect ratio of the unreinforced masonry wall, and the vertical strength, 2) to propose the equation of the shear capacity of masonry wall by regression analysis using the test data.

상호작용하는 두 개의 신경세표의 결합 원사상 모형

김치용,유영종,이상훈 인제대학교기초과학연구소 1997 자연과학 Vol.1 No.-

두 개의 상호작용하는 신경세포들의 동력학을 기술하는 두 개의 확산결합된 선형적으로 또는 비선형적으로 이질적인 2차원 원사상의 2보차원 등주기갈래질의 전역구조를 전산모사하였다. 회전수집합과 리야프노프지수를 계산하여 결합한 원사상의 주기적 상태, 두 주파수 또는 세 주파수와 관련된 준주기 상태, 그리고 혼돈 및 초혼돈적 상태들을 분류하는 기준을 설정하였다. 아놀드의 혀 및 주기적 새우 구조와 같은 동위상 또는 반위상 동조가 선형 또는 비선형 매개변수 공간에서 발견되어 결합계에서의 혼돈 갈래질의 보편적구조를 확인하였다. We analyse the codimentsin-two isoperiodic bifurcatin diagrams of two homogeneous and heterogeneous diffusively coupled circle mape. In-phase or out-of-phase periodic states, two-frequency or three-frequency quasi-periodic states, chaotic, and hyperchaotic states are graphically classified and charac-terized by rotaion set and lyapunov specturm. In-phase or out-of-phase Entrainment such as Amold's tongues and peridic shrimps appear in quasiperiodic or chaotic area of the linear or nonlinear parameter space. We also discuss the relevance of entrainment in coupled neural systems.