• 한국전자파학회:학술대회논문집
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• 한국전자파학회 2001년도 종합학술발표회 논문집 Vol.11 No.1
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• pp.319-324
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• 2001

An anatomical head and a multi-layered spherical head with a half-wave handset antenna have been analysed and compared using the Finite-Difference Time-Domain (FDTD) and the Eigenfuntion Expansion Method (EEM), respectively. The analysis shows that results from a simple spherical head with a half-wave antenna can be used to predict the main antenna radiation patters as well as estimates of the peak SAR in a handset user's head. Various representative design data are presented using a six-layered spherical head with a half-wave antenna at 900 MHz

• 디지털융복합연구
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• 제11권2호
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• pp.243-248
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• 2013

본 논문에서는 복잡한 배경에서의 사람의 머리 추적에 있어서 효과적인 Adaptive Boosting에 의한 방법을 제안한다. 하나의 특징 추출 방법은 사람의 머리를 모델링하기에는 부족하다. 따라서 본 연구에서는 여러 가지 특징 추출 방법을 병행하여 정확한 머리 검출을 시도하였다. 머리 영상의 특징 추출은 sub-region과 Haar 웨이블릿 변환(Haar wavelet transform)을 이용하였다. Sub-region은 머리의 지역적인 특징을 나타내고, Haar 웨이블릿 변환은 얼굴의 주파수 특성을 나타내기 때문에 이들을 이용하여 특징을 추출하면 효과적인 모델링이 가능해 진다. 실시간으로 입력되는 영상에서 사람의 머리를 추적하기 위하여 제안하는 방법에서는 3가지 형태의 Harr-wavelet 특징을 AdaBoosting 알고리즘으로 학습한 후 결과를 이용하였다. 원래 AdaBoosting 알고리즘은 학습시간이 매우 길며 학습데이터가 변하면 다시 학습을 수행해야 하는 단점이 존재한다. 이 단점을 극복하기 위하여 제안하는 방법에서는 캐스케이드를 이용한 AdaBoosting의 효율적인 학습방법을 제안한다. 이 방법은 머리 영상에 대한 학습시간은 감소시키며, 학습데이터의 변화에도 효율적으로 대처할 수 있다. 이 방법은 학습과정을 레벨별로 분리한 후 중요도가 높은 학습데이터를 다음 단계에 반복적으로 적용시킨다. 제안하는 방법이 적은 학습 시간과 학습 데이터를 사용해서 우수한 성능을 가지는 분류기를 생성하였다. 또한, 이 방법은 다양한 머리데이터를 가진 실시간 영상데이터에 적용한 결과 다양한 머리를 정확하게 검출 및 추적하였다.

• 한국병원경영학회지
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• 제21권3호
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• pp.37-52
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• 2016

The purpose of this study was to analyze the job of Head hospital coordinators based on the DACUM(Developing A Curriculum) method. The contents of this study were to extract the duties, tasks and performance standards consisting of the job of a Head hospital coordinator and to investigate levels of importance, difficulties, frequency and entry level on each task, and to make out a job model of Head hospital coordinators. A DACUM committee(seven members) was composed to analyze the job of Head hospital coordinators and the committee members were totally nine : a facilitator, seven Head hospital coordinators and a recorder. This study was conducted in Seoul and Gyeonggi Province from August to December, 2015. The major findings of this study were as follows; first, a Head hospital coordinator is defined to be an expert to create values and culture of a hospital, plan and manage hospital's efficient management methods to maximize customer satisfaction and improve the management of a hospital. Second, the job of Head hospital coordinators was categorized into total nine duties and sixty eight tasks. Third, duties in the job of Head hospital coordinators were classified into organization of medical management planning, medical management analysis, medical service quality management, hospital marketing, hospital customer management, hospital human resource management, hospital organization management, hospital financial management and self development.

• 한국음향학회지
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• 제20권6호
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• pp.94-103
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• 2001

수치해석 방법을 이용하여 실험으로 구한 머리전달함수 (Head Related Transfer Function: HRTF)를 컴퓨터 시뮬레이션으로 대치하고, 청취자의 머리 주변에서의 음장을 가시화하는 방법에 대해 다룬다. 본 논문에서는 경계요소법 (Boundary Element Method)과 무한요소법 (Infinite-Finite Element Method)의 두 가지 방법을 이용한다. 지금까지는 더미헤드 (Dummy-Head)등을 이용한 실험으로 머리전달함수를 구하였는데 이 실험에는 상당한 시간과 장비가 필요하다. 3차원 레이저스캐너를 이용하여 KEMAR 더미헤드의 형상을 측정하고 이것을 여러 다른 요소 수를 가지는 경계요소모델 및 무한요소모델로 변환하여 머리전달함수를 계산하고 모델의 요소 크기와 적용 가능한 주파수 대역과의 관계에 대해 분석한다. 측정을 통해 구한 머리전달함수와 비교하여 모델을 검증하고 음향학의 상반원리를 적용하여 머리전달함수의 데이터베이스를 구한다. 또한 몇 가지 가상음향 시스템에 대한 음장해석을 통해 주파수 및 시간영역에서의 음장을 가시화한다.

• 대한치과교정학회지
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• 제35권5호
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• pp.341-350
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• 2005

두부방사선규격사진에서는 매 촬영 시마다 두부의 수직적 회전 정도를 일정하게 유지하기 위하여 두부자세의 재현이 필요하다 본 연구는 유도방법에 따른 자연두부자세의 수직적 두부회전 정도의 차이를 비교하고 각 두부자세의 재현성을 평가하기 위하여 시행되었다 20대 성인 남녀 30명을 연구대상으로 하여 head posture aligner를 이용한 방법(HPA법)과 self balance posture를 이용한 방법(SBP법)으로 자연두부자세를 유도하여 측모 및 정모두부방사선규격사진을 각각 한 달 간격으로 촬영한 후, 측모두부방사선규격사진 상에서 유도 방법에 따른 수직적 두부회전 정도의 차이를 비교하는 한편, 측모 및 정모두부방사선규격사진에서 시간 간격을 두고 동일 방법으로 유도하여 촬영한 두 사진 상의 동일 계측항목 간 차이를 비교함으로써 각 두부자세의 유도방법에 대한 재현성을 평가하였다 연구결과 SBP법으로 유도한 자연두부자세는 HPA법에 의해 유도된 자연두부자세보다 평균 $2.79^{\circ}$ 고개를 숙인 자세로 나타났다. 또한 HPA법 또는 SBP법을 이용하여 시간 간격을 두고 각각 2회 촬영한 측모두부방사선규격사진과 정모두부방사선규격사진 상의 계측치는 모든 계측항목에서 통계적으로 유의한 차이를 보이지 않는 것으로 나타났다. 본 연구 결과는 HPA법과 SBP법으로 유도한 자연두부자세가 모두 재현성이 있음을 나타내는 것으로 두부방사선규격사진 촬영 시 재현성을 높이기 위하여 HPA법과 더불어 SBP법도 임상적으로 사용될 수 있음을 시사하였다.

• 대한인간공학회지
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• 제16권3호
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• pp.1-10
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• 1997

This paper is concerned with the development and evaluation of the camera calibration method for a real-time head tracking system. Tracking of head movements is important in the design of an eye-controlled human/computer interface and the area of virtual environment. We proposed a video-based head tracking system. A camera was mounted on the subject's head and it took the front view containing eight 3-dimensional reference points(passive retr0-reflecting markers) fixed at the known position(computer monitor). The reference points were captured by image processing board. These points were used to calculate the position (3-dimensional) and orientation of the camera. A suitable camera calibration method for providing accurate extrinsic camera parameters was proposed. The method has three steps. In the first step, the image center was calibrated using the method of varying focal length. In the second step, the focal length and the scale factor were calibrated from the Direct Linear Transformation (DLT) matrix obtained from the known position and orientation of the camera. In the third step, the position and orientation of the camera was calculated from the DLT matrix, using the calibrated intrinsic camera parameters. Experimental results showed that the average error of camera positions (3- dimensional) is about $0.53^{\circ}C$, the angular errors of camera orientations are less than $0.55^{\circ}C$and the data aquisition rate is about 10Hz. The results of this study can be applied to the tracking of head movements related to the eye-controlled human/computer interface and the virtual environment.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권2호
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• pp.45-53
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• 2013

Many cases of strategically designed groundwater remediation have lack of information of hydraulic conductivity or permeability, which can render remediation methods inefficient. Many studies have been carried out to minimize this shortcoming by determining detailed hydraulic information either through direct or indirect measurements. One popular method for hydraulic characterization is the pilot point method (PPM), where the hydraulic property is estimated at a small number of strategically selected points using secondary measurements such as hydraulic head or tracer concentration. This paper adopted a D-optimality based pilot point method (DBM) developed previously for hydraulic head measurements and extended it to include both hydraulic head and tracer measurements. Based on different combinations of trials, our analysis showed that DBM performs well when hydraulic head is used for pilot point selection and both hydraulic head and tracer measurements are used for determining the conductivity values.

• 대한간호학회지
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• 제14권2호
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• pp.5-11
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• 1984

The main purpose of this study were; to determine the reliability and validity of evaluation tool administered to the nursing student in nursing management practice,；to identify the effective evaluation method of nursing student in nursing management practice. The subjects were 46 senior nursing students at Department of Nursing, College of Medicine, Seoul National University in 1983. The evaluation tool was analyzed according to evaluation method; self-evaluation. and head nurse evaluation. Also individual item of evaluation tool was analyzed by item analysis in order to determine the evaluation area, and appropriateness of the test item used. A Summary of the results is as follows; 1. The reliability and validity of evaluation tool were relatively high both in self-evaluation and head nurse evaluation. 2. In comparison of mean scores, there is no significant difference between head nurse evaluation and self-evaluation. 3. The nursing management activities which have the correlation of self-evaluation and head nurse evaluation were in the activity of interpersonal relation, independent activity and implementing nursing process. In general nursing practice and unit management activity, there was no correlation of self-evaluation and head nurse evaluation.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 Ⅳ
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• pp.1887-1890
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• 2003

This paper presents a three-dimensional (3D) head pose estimation algorithm using the stereo image. Given a pair of stereo image, we automatically extract several important facial feature points using the disparity map, the gabor filter and the canny edge detector. To detect the facial feature region , we propose a region dividing method using the disparity map. On the indoor head & shoulder stereo image, a face region has a larger disparity than a background. So we separate a face region from a background by a divergence of disparity. To estimate 3D head pose, we propose a 2D-3D Error Compensated-SVD (EC-SVD) algorithm. We estimate the 3D coordinates of the facial features using the correspondence of a stereo image. We can estimate the head pose of an input image using Error Compensated-SVD (EC-SVD) method. Experimental results show that the proposed method is capable of estimating pose accurately.

• 로봇학회논문지
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• 제5권3호
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• pp.262-269
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• 2010

This paper presents a probabilistic head tracking method, mainly applicable to face recognition and human robot interaction, which can robustly track human head against various variations such as pose/scale change, illumination change, and background clutters. Compared to conventional particle filter based approaches, the proposed method can effectively track a human head by regularizing the sample space and sequentially weighting multiple visual cues, in the prediction and observation stages, respectively. Experimental results show the robustness of the proposed method, and it is worthy to be mentioned that some proposed probabilistic framework could be easily applied to other object tracking problems.