• 대한기계학회논문집A
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• 제24권5호
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• pp.1271-1280
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• 2000

A sensor placement technique to identify structural parameter was developed. Experimental results must be acquired to identify unknown dynamic characteristics of a targeting structure for the comparison between analytical model and real structure. If the experimental environment was not equipped itself properly, it can be happened that some valuable information are distorted or ill-condition can be occurred. In this work the index to determine exciting points was derived from the criterion of maximizing parameter sensitivity matrix and that to choose measurement points was from that of preserving the invariant of sensitivity matrix. This idea was applied to a compressor hull structure to verify its performance. The result shows that the selection of measurement and excitation points using suggested criteria improve the ill-conditioning problem of inverse type problems such , as model updating.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.2
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• pp.91-96
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• 2006

Presently, cycle-slip detection is done between adjacent two points in many cycle-slip methods. Inherently, it is simple wavelet analysis. A new idea is put forward that the number of difference point can adjust by a parameter factor; we study this method to smooth raw data and detect cycle-slip with wavelet analysis. Taking CHAMP satellite data for example, we get some significant conclusions. It is showed that it is valid to detect cycle-slip in GPS phase measurement based on this wavelet function, and it is helpful to improve the precision of GPS data pre-processing and positioning.

• International Journal of Control, Automation, and Systems
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• 제3권4호
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• pp.542-551
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• 2005

A new distance measurement method with the use of a single camera and a rotating mirror is presented. A camera in front of a rotating mirror acquires a sequence of reflected images, from which distance information is extracted. The distance measurement is based on the idea that the corresponding pixel of an object point at a longer distance moves at a higher speed in a sequence of images in this type of system setting. Distance measurement based on such pixel movement is investigated. Like many other image-based techniques, this presented technique requires matching corresponding points in two images. To alleviate such difficulty, two kinds of techniques of image tracking through the sequence of images and the utilization of multiple sets of image frames are described. Precision improvement is possible and is one attractive merit. The presented approach with a rotating mirror is especially suitable for such multiple measurements. The imprecision caused by the physical limit could be improved through making several measurements and taking an average. In this paper, mathematics necessary for implementing the technique is derived and presented. Also, the error sensitivities of related parameters are analyzed. Experimental results using the real camera-mirror setup are reported.

• 벤처창업연구
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• 제13권4호
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• pp.197-209
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• 2018

최근 창업을 권장하는 사회적 분위기 속에서 창업하고자 하는 시도가 늘어나는 만큼 창업실패 사례도 다수 발생하고 있다. 특히 청년창업은 일반창업보다 생존율이 낮게 나타났는데, 청년 창업자는 기업경영에 관한 사전 지식과 경험이 부족한 상태에서 취업의 어려움을 뛰어넘기 위해 단순한 아이디어만으로 창업에 도전하는 사례가 많아 성공보다는 실패하는 경우가 많다. 그러므로 창업실패의 원인은 창업 준비부족과 창업역량 부족이라고 할 수 있다. 이에 본 연구에서는 청년층을 대상으로 창업역량 개발과 창업 준비 활동을 위한 기본적 틀을 구축할 수 있도록 측정 도구를 개발하는 것에 목적을 둔다. 창업역량 측정 도구를 개발하기 위해 먼저 정성적 연구방법인 문헌연구, 초점집단 인터뷰, 전문가 검증을 통하여 예비문항을 개발하였다. 이후 정량적 연구방법을 사용하여 창업자 102명을 대상으로 설문조사를 하였고, 측정 도구의 구성 타당도 검증을 위해서 탐색적 요인분석과 확인적 요인분석 과정을 거쳐 최종 창업역량 측정 도구를 완성했다. 본 연구 과정을 통해서 개발된 창업역량 측정 도구는 7개의 구성요인과 15개의 측정 문항으로 구성된다. 먼저 창업 의지확인단계에는 자기 분석력 2개 문항, 창업철학 정립 능력 3개 문항이며, 창업모델구상단계에서는 창업 아이디어 도출능력, 아이디어 타당성 분석력, 벤처창업 모델 기획력에서 각 2개 문항씩, 벤처창업계획단계에서는 사업계획 프레젠테이션 능력, 조직 시스템 구축 능력에서 각 2개 문항으로 구성된다. 본 연구에서 개발된 창업역량 측정 도구는 청년 창업자 또는 예비 청년 창업자가 창업 초기 단계에서 자신의 창업역량을 측정해 봄으로써 창업을 준비하는 데 있어 부족한 역량을 알아보고, 필요로 하는 역량을 함양하는 데 도움을 줄 수 있으며, 창업교육에서는 청년 창업자의 창업역량을 진단해 볼 수 있는 기초적 자료를 제공하는 데 의의가 있다.

• 지질공학
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• 제10권1호
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• pp.63-77
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• 2000

The dipole method is now popular means for S-wave logging. Essential features of this method are explained, emphasizing basic concept based on approximation of the long-wavelength and the far-field. History of my researches concerned is shortly reviewed as background to reach the idea of this method. Short wavelength behavior of the dipole method is simply reviewed. Methods to reject tube wave noise are commented.

• 한국정밀공학회지
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• 제4권2호
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• pp.36-46
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• 1987

An optical technique using laser for non-contact measurement of surface roughness and form accuracy of ground surfaces is presented. It is found that, when a ground surface is illuminated by a beam of laser light, the roughness height and slope distribution has significant influence on the pattern of reflection and it maintains an unique Gaussian distribution relationship with the surface roughness. The principle idea of the optical measurement system is therefore monitor the radiation, and then calibrate it in process against surface roughness by means of necessary digital data processing. On the other hand, measuring the form accuracy of a ground surface is accomplished by using a triangular method, which is based on observing the movement of an image of a spot of light projected onto the surface. The image is focused, through a series of lenses for magnification, on a photodetector array lf line configur- ation. Then the relative movement of image and consequently the form accuracy of the surface can be obtained through appropriate calibration procedures. Experimental test showed that the optical roughness measurement technique suggested in this work is very efficient for most industrial applications being capable of monitoring the roughness heights ranging 0.1 to 0.6 .$\mu$m CLA values. And form accuracy can be measured in process with a resolution of 10 .$\mu$m.

• International Journal of Control, Automation, and Systems
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• 제3권1호
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• pp.130-136
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• 2005

A new optical digitizing system for determining the position of a cursor in three dimensions(3D) and an experimental device for its measurement are presented. A semi-passive system using light intensity modulation, a technology that is well known in radar ranging, is employed in order to overcome precision limitations imposed by background light. This system consists of a charge-coupled device camera placed before a rotating mirror and a light-emitting diode whose intensity is modulated. Using a Fresnel pattern for light modulation, it is verified that a substantial improvement of the signal to noise ratio is realized for the background noise and that a resolution of less than a single pixel can be achieved. This opens the doorway to the realization of high precision 3D digitized measurement. We further propose that a 3D position measurement with a monocular optical system can be realized by a numerical experiment if a linear-period modulated waveform is adopted as the light-modulating one.

• 대한수학교육학회지:수학교육학연구
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• 제15권3호
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• pp.233-249
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• 2005

이 논문에서는 분수의 역사발생 과정을 분석함으로써 분수 개념이 측정 과정에서 유래되었음을 밝히고, 이를 활용하여 측정 과정을 통하여 초등학생들에게 분수를 지도할 것을 제안하였다. 여러 연구에서는 많은 초등학생들이 현행 교육과정에서 6학년에 도입되는 비 개념에 대한 예비 활동으로서 3학년부터 지속적으로 다루어지고 있는 분수의 여러 의미를 파악하지 못하고 있음을 보여주고 있다. 연구자는 선행 연구와 교재 분석을 통하여 이러한 문제점이 분수의 다양한 의미를 다루는 방식에서 학생들에게 혼란을 초래할 수 있음을 논하였다. 그리고 이에 대한 대안적인 방법의 하나로서, 측정 과정을 통하여 초등학교에서 분수를 도입할 것을 주장하였다.

• 기술혁신연구
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• 제6권1호
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• pp.163-186
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• 1998

The psychological work environments which facilitate technology innovations in organizations are divided into two dimensions of supportive work environments and uncertain work environments. The measurement variables have significant reliability. And the confirmatory factor analysis confirm the construct validity of two dimensional work environments. Two work environments have the significant effects on motivations to the technology innovations. So, simple and hierarchical regression analyses confirm criterion-related validity. Therefore, Both of the uncertain work environments(uncertainty of external-organizational environments and tasks) and the two important work environments(supporting idea, resource supply, job autonomy) are the two important psychological work environments which indicate technology innovations in organizations. Measures for innovative psychological work environments are provided.

• 한국생산제조학회지
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• 제5권2호
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• pp.57-62
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• 1996

Basically, the idea underlying most edge-detection technique is the computation of a local derivative operator used for edge detection in gray level image. This concept can be easily illustrated with the aid of object which shows an image of a simple lilght on a dark background, Using the gray level profile along a horizontal scan line of the image. the first and second derivatives of it were acquired. This study is to develop an automatic measuring system based on the digital image processing which can be applied to the real time measurement of the characteristics of the ultra-thin thickness. The experimental results indicate that the developed automatic inspection can be applied in real situation.