• Journal of Biomedical Engineering Research
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• v.15 no.2
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• pp.217-224
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• 1994

In order to study the shape and dimensions of heart, a procedure to reconstruct a three dimensional left ventricular geometry from two dimensional echocardiographic images was studied including the coordinate transformation, curve fitting and interpolation utilizing three dimensional position registration arm. Nonlinear material property of the left ventricular myocardium was obtained by finite element method performed on the reconstructed geometry and by optimization techniques which compared the computer predicted 3D deformation with the experimentally determined deformation. Elastic modulus ranged from 3.5g/$cm^2$ at early diastole to l53g/$cm^2$ at around end diastole showing slightly nonlinear relationship between the modulus and the pressure. Afterwards using the obtained nonlinear material propertry the stress distribution related with oxyzen consumption rate was analyzed. The maximum and minimum of ${\sigma}_1$ (max. principal stress) occurred at nodes on the second level intersection points of x-axis with endocardium and with epicardium, respectively. And the tendency of the interventricular septum to be flattened was observed from the compressive ${\sigma}_1$ on the anterior, posterior nodes of left ventricle and from the most significant change of dimension in $D_{RL}$ (septal-lateral dimension of right ventricle).

• Progress in Medical Physics
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• v.8 no.2
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• pp.19-26
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• 1997

3-dimensional Neuronavigator, Viewing Wand(ISG Technologies, Toronto, Cannda) is the surgery aid equipment for real time image (CT or MRI) guided surgery. The assurance of spatial accuracy of this system is important for clinical application. In this study, we have designed the acrylic brain phantom and measured the spatial error with that phantom. The phantom has designed to have capability to simulate image guided surgery. The phantom has 22 vertical rods whose diameters are 5mm and each rods has different length. CT scans were performed by 2.0mm slice and reconstructed for 3-Dimensional analysis. End point of rods can be obtained using reconstructed 3- Dimensional images and they are compared to actual position data. Average deviation was less than 2mm for various situations. Spatial error of Viewing Wand is acceptable in the clinical points of view, while cosmetics of the software needs to be modified to more user friend. Better accuracy can be expected when we apply the mixed fiducial fit registration and surface fit registration method. And even better results can be obtained if registration points distributed even and symetric around the target.

• Proceedings of the Korean Information Science Society Conference
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• 2004.10b
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• pp.592-594
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• 2004

문서 영상 획득(document scanning)은 문서 영상 분석과 인식을 위한 중요한 단계이다 최근, 문서 영상 획득 장치로 스캐너(flat scanner)가 가장 많이 이용되고 있지만, 만지면 망가질 것 같은 얇은 고서, 매우 두꺼운 책과 같은 문서를 획득하기에는 어려움이 있다 이런 어려움을 해결하기 위해, 카메라를 이용한 문서 영상 획득에 관한 않은 연구가 진행되고 있으며, 카메라의 저해상도나 잡음과 칼은 문제를 해결하면, 스캐너를 대신하는 입력 장치로 이용할 수 있다. 저해상도 문제를 해결하는 방법으로 기본의 일반적인 레지스트레이션(registration) 방법은, 연결 부분(stitching position)에서 오브젝트(object: text, graphics, image)의 왜곡이 생기는 문제점이 있다. 본 논문에서는 PTZ(pan-tilt-zoom) 카메라를 이용하여 연결 부분에서 왜곡을 최소화하여 오브젝트를 획득하는 컴포넌트 기반의 영상 레지스트레이션(component-based image registration) 방법을 제안한다. 제안한 방법은 연결 부분에서 오브젝트의 수를 최소화하는데 목적이 있으며, 일반적인 레지스트레이션 방법에 비해 연결 부분에서 왜곡을 상당히 줄일 수 있으며, 상대적으로 인식률을 놓일 수 있다.

• Proceedings of the Korea Society of Costume Conference
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• 2003.10a
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• pp.75-75
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• 2003

The distinctive design of apparel product is the crucial factor that provides the powerful competitive advantage and customer satisfaction. However, knock-offs or copycats easily copy the design of apparel product and its problem tends to be assented in real world. Design right is one of intellectual property rights that would be produced by intellectual activity and the appropriate means to establish the exclusive rights to the design should be established. Legal protection to the design right is the system that can prelude copycats from eroding an exclusive position in the market place. The present study was to analyze the trend of registration of design rights in apparel products and to point out problems of current protection law to design.

• Ocean Systems Engineering
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• v.1 no.3
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• pp.195-205
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• 2011

A method for calibrating a laser profiling system for seafloor micro-topography measurements is described. The system consists of a digital camera and an arrangement of six red lasers that are mounted as a unit on a remotely operated vehicle (ROV). The lasers project as parallel planes onto the seafloor, creating profiles of the local topography that are interpreted from the digital camera image. The goal of the calibration was to determine the plane equations for the six lasers relative to the camera. This was accomplished in two stages. First, distortions in the digital image were corrected using an interpolation method based on a virtual pinhole camera model. Then, the laser planes were determined according to their intersections with a calibration target. The position and orientation of the target were obtained by a registration process. The selection of the target shape and size was found to be critical to a successful calibration at sea, due to the limitations in the manoeuvrability of the ROV.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2004.03a
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• pp.613-616
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• 2004

Recently, in a field of cadastre, a computerization of cadastral map is in progress with great growth of GSIS field. Also, the needs for the integration of land and building information are widely increasing for integral-management and its application of various land related information. Through a revision of cadastral laws to replace the existing 2D-Cadastre with the 3D-Cadastre, a legal basis to register the position of buildings and facilities is prepared in the governmental or civil fields. This paper presented 3D-Cadastre theory that has been studied on Europe and surveyed building position directly with Totalstation at cadastral control point after choosing pilot test area, Also, the most efficient surveying method of registering building in a cadastral map is presented with comparing and analyzing building position after surveying digital orthophoto and digital map.

• Journal of Preventive Medicine and Public Health
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• v.40 no.3
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• pp.233-238
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• 2007

Objectives : We aimed to assess the relationship between long-term exposure to air pollution and lung cancer in the Republic of Korea. Methods : Using the Annual Report of Ambient Air Quality in Korea, Annual Report of National Cancer Registration, and Annual Report on the Cause of Death Statistics, we calculated the standardized mortality ratio (SMR) and standardized incidence ratio (SIR) of lung cancer for both sexes in 74 areas from 7 Korean metropolitan cities. We performed random intercept, Poisson regression using empirical Bayes method. Results : Both SMRs and SIRs in the 7 metropolitan cities were higher in women than in men. Mean SIRs were 99.0 for males and 107.0 for females. The association between $PM_{10}$ and lung cancer risk differed according to gender. $PM_{10}$ was not associated with the risk of lung cancer in males, but both incidence and mortality of lung cancer were positively associated with $PM_{10}$ in females. The estimated percentage increases in the rate of female lung cancer mortality and incidence were 27% and 65% at the highest $PM_{10}$ category $({\geq}70\;{\mu}g/m^3)$, compared to the referent category $({\geq}50\;{\mu}g/m^3)$. Conclusions : Long-term exposure to $PM_{10}$ was significantly associated with female lung cancer incidence in 7 Korean metropolitan cities. Further study is undergoing to estimate the relative risk of $PM_{10}$ using multi-level analysis for controlling individual and regional confounders such as smoking and socioeconomic position.

• The Korean Journal of Nuclear Medicine Technology
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• v.23 no.1
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• pp.59-63
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• 2019

Purpose The motion due to respiration of patients undergoing PET/CT is a cause of artifacts in image and registration error between PET and CT images. The degree of displacement and distortion for tumor, which affects the measurement of Standard Uptake Value (SUV) and lesion volume, is especially higher for tumors that is small or located at the base of lungs. The purpose of this study was to evaluate the usefulness of prone position in the correction of image distortion due to respiration of patients in PET/CT. Materials and Methods The imaging equipment used in this study was PET/CT Discovery 600 (GE Healthcare, MI, USA). 20 patients whose lesions were identified in the middle and lower lungs from May to August 2018 were enrolled in this study. After acquiring whole body image in the supine position, additional images of the lesion area were obtained in the prone position with the same conditions. SUVmax, SUVmean, and volume of the lesion were measured for each image, and the displacement of the lesion on PET and CT images were measured, compared, and analyzed. Results The SUVmax, SUVmean, and volume, and displacement of the lesion were $4.72{\pm}2.04$, $3.10{\pm}1.38$, $4.68{\pm}3.20$, and $4.64{\pm}1.88$, respectively for image acquired in the supine position and $5.89{\pm}2.42$, $3.97{\pm}1.65$, $2.13{\pm}1.09$, and $2.24{\pm}0.84$, respectively for image acquired in the prone position, indicating that, for all the lesions imaged, SUVmax and SUVmean were higher and volume and displacement were smaller in the images acquired in prone position compared to those acquired in supine one(p<0.05). Conclusion These results showed that the prone position PET/CT imaging improves the quality of the image by increasing the SUV of the lesion and reducing the respiratory artifacts caused by registration error between PET and CT images. It is considered that the PET/CT imaging in the prone position is helpful in the diagnosis of the disease as an economical and efficient methods that correct registration error for the lesions in basal lung and reduce artifacts.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.119.3-119
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• 2002

$\textbullet$ A bone-mountable surgical robot system for hip surgery $\textbullet$ A simple gauge-based registration method $\textbullet$ A proposed surgical procedure $\textbullet$ Evaluation method for position/orientation accuracy $\textbullet$ Evaluation method for surface conformity $\textbullet$ The performance evaluation of ARTHROBOT $\textbullet$ Summary

• The Journal of Korean Academy of Prosthodontics
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• v.33 no.4
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• pp.769-779
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• 1995

The understanding the nature of occlusal tooth contacts of natural dentition is important for correct diagnosis and treatment of diseases developed in stomatognatic system. Several investigator have studied the distribution of tooth contacts in maximum intercuspation and have repored contact locations with respect to the tooth position. However, there are few report the variation of the occlusal contact point with change in each head position. This study analysed the number of occlusal contact point with change in each head position. 30 subject(male 17, female 13), who ahad natural occlusion and no symptoms of temporomandibular disorder, were selected. The numbers and patterns of tooth contact were recorded by silicone bite registration on stone model at four different head positions with head anguration gauge(from the supine to the upright position). The results obtained were as follows : 1. The numbers of total occlusal contact point on teeth increased to average 25, 29, 35, 42 points as head angulation was changed from the supine to the upright position against the ala-tragus line, and there was significant difference(P<0.05). 2. In the 19 subject(65%)of total 30 subject, the perforated point of the silicone bite indicated that the locus for the prime contact point moved mesially as the head angulation was changed from the supine to the upright position. 3. On the basis of the fact that the anterior occlusal contact point increase as head angulation changed from the supine to the upright position, we could find that the mandibular position is moved anteriorly.