• 한국지구물리탐사학회:학술대회논문집
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• 2005.05a
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• pp.129-136
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• 2005

The groundwater survey was carried out by electrical resistivity and resistivity tomography using several kinds of electrode array to delineate the depth of the saturated zone and basement complex, the aquifer system of fractured rock, and the 2-D resistivity structure was obtained by inversion technique. And the hole-to-surface and crosshole tomography were applied for two boreholes and the inverted resistivity tomogram are obtained. The comparison of those data with core logging data was performed and those results were relatively well correlated. And it was possible to find out the configuration of basement and the fracture zone and the aquifer system from the 2-D resistivity structure and resistivity tomogram.

• The korean journal of orthodontics
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• v.22 no.1
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• pp.89-107
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• 1992

The purpose of this study was to investigate the difference between normal and malocclusion subjects in Temporomandibular joint. This study was based on the 44 subjects with normal occlusion, 30 subjects with Class II malocclusion, 30 subjects with Class III malocclusion before treatment. After submental vertex view analysis, each subject was given the TMJ Tomogram in centric relation and centric occlusion and the Cephalogram was taken with Quint Sectograph. The TMJ spaces were measured and analyzed statistically. Following results were obtained. 1. When centric relation was compared to centric occlusion, The condyles were positioned more posteriorly and superiorly in centric relation position of the normal occlusion group and the class II malocclusion group. In the Class III malocclusion group. There was no significant difference in the condylar position between centric occlusion and centric relation. 2. The condyles of the Class III malocclusion group were positioned more superiorly than the normal occlusion group and the Class II malocclusion group. 3. In the correlation between articular eminence posterior slope angle and lingual slope angle of the upper anterior central incisor, there was significant correlation in the normal occlusion group. But no significant correlation was found in the malocclusion group. 4. The mean value of the horizontal angulation of condylar head to the transear rod axis plane was $20.32^{\circ}{\pm}8.12^{\circ}$ in the normal occlusion group, $25.08^{\circ}{\pm}4.83^{\circ}$ in the class II malocclusion group, $14.68^{\circ}{\pm}4.08^{\circ}$ in the class III malocclusion group.

• Korean Journal of Bronchoesophagology
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• v.18 no.2
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• pp.49-55
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• 2012

Background and Objectives This study was conducted to gather three dimensional images from computed tomogram in detecting and gaining information about fish bones. Materials and Methods Thirty-nine fish bones and 2 chicken leg bones were used. Bones sandwiched between the cotton sheets were placed into the 3 plastic boxes. Computed tomogram of the bones in the boxes were reconstructed three-dimensionally by Xelis (Infinitt, Korea) to make images of MPR, MIP and VR images. The images were compared with real chicken bones and fish bones as to possibility of detection, finding of location and orientation, and evaluation of shape and calculation of size. Results All 41 bones were detected in all reconstructed images. Distance to the bones from reference point can be measured and orientation can be checked. Shapes were similar between matched images of all real bones. Conclusion The results indicate the usefulness of 3D reconstruction technique in getting informations about fish bones.

• Annual Conference of KIPS
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• 2009.11a
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• pp.395-396
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• 2009

Electron tomography를 이용한 3차원적 영상 시각화는 electron microscopy를 통해 하나의 실험 대상으로부터 연속된 이미지를 생산함으로써 이루어진다. 이미지 데이터 내부에는 대용량의 정보값을 포함하고 있어 3차원 구조물로의 변환이 가능하다. electron tomography 작업 과정 중 고해상도 원본 이미지에 pattern recognition 알고리즘이 적용된 필터링을 적용하면 실험에 필요한 데이터의 정보 손실을 최소화한 상태에서 electron tomography 시스템의 효율성을 높일 수 있다. 또한 tomographic econstruction이 진행되는 각 단계에 hanning windowing을 적용하면 불필요한 정보 값이나 노이즈 등을 효과적으로 제거할 수 있다. 윤곽선 데이터의 효과적 활용을 위하여 sobel 필터 처리를 할 경우 관찰하고자 하는 대상의 윤곽선 특징을 뚜렷하게 시각화 할 수 있었다. 본 연구를 통하여 데이터의 시각화 과정에서 실험의 신뢰성 확보를 위해 원본 이미지를 기반으로 하는 tomogram과 필터링을 적용한 tomogram을 비교하여 최종 결과물의 정확도를 높이고, electron tomography를 통한 결과물의 질적 향상을 유도할 수 있음을 확인하였다.

• Journal of Korean Tunnelling and Underground Space Association
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• v.11 no.4
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• pp.361-371
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• 2009

Resistivity tomography is very effective geophysical method to find out the resistivity distribution and its change in time around a tunnel. Thus, the resistivity tomogram can provide helpful information which is necessary for the effective maintenance of the tunnel. However, an air filled tunnel severely distorts tomography data, especially when the current or potential electrode is placed near the tunnel. Moreover, the distortion can often lead to misinterpretation of tomography monitoring data. To solve these problem, we developed a resistivity modeling and time-lapse inversion program which include a tunnel. In this study, using the developed program we assured that the inversion including a tunnel gives much more accurate image around a tunnel, compared with the conventional tomogram where the tunnel is not included. We also confirmed that the time-lapse inversion of resistivity monitoring data defines well resistivity changed areas around a tunnel in time.

• Journal of Industrial Technology
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• v.20 no.A
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• pp.285-293
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• 2000

In 1970's, the analysis of shallow substructure was the interests of geological engineering and environmental problems. And seismic refraction method was applied to detect those structures. From 1980's, digital electric industry is rapidly developed and high resolution prospecting equipment is supplied. And seismic reflection method is applied to achieve various data gathering and data analysis. In this study, geophysical prospecting method is applied to calculate the basic data of limestone yield production. Seismic shallow reflection method is used to detect the depth of bedrock and electrical resistivity method is used to detect of limestone layer boundary.

• Advances in pediatric surgery
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• v.1 no.2
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• pp.204-208
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• 1995

Neonatal adrenal hemorrhage is frequently associated with birth trauma or perinatal hypoxia. Hemorrhagic necrosis of the adrenal glands is often found at autopsy and many small lesions are usually asymptomatic. A palpable abdominal mass and jaundice are the usual presenting signs. Ultrasound is very useful in the diagnosis of this lesion; however, if the mass has mixed echoic pattern, magnetic resonance imaging (MRl) is helpful for the differential diagnosis from neuroblastoma. We present the case of a female newborn who was found to have a abdominal mass on physical examination. The patient showed anemia and hyperbilirubinemia. An ultrasonogram disclosed a $3.8{\times}3.0$ cm suprarenal mass with mixed echoic pattern. The mass was initially suspected to be neuroblastoma. An abdominal computed tomogram was not able to differentiate the mass. Magnetic resonance imaging revealed markedly increased signal intensity on T1 and T2-weighted sequences. This finding was consistent with adrenal hemorrhage. Serial sonogram demonstrated the mass that resolved completely by 12 weeks of age.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.26 no.6
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• pp.811-816
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• 2002

For the first time, airflow in the nasal cavity of a normal Korean adult is investigated experimentally by PIV measurement. Nasal airflow can be subdivided into two interrelated categories; nasal airflow resistance and heat and mass transfer between the air stream and the walls of the nasal cavity. In this study, thanks to a new method for the model casting by a combination of the rapid prototyping and curing of clear silicone. a transparent rectangular box containing the complex nasal cavity can be made fur PIV experiments. The CBC PIV algorithm is used for analysis. Average and RMS distributions are obtained for inspirational and expiration nasal airflows. Data fer the airflow at the end of meatuses are obtained for the first time. Comparisons between western and Korean nasal airflows are appreciated. Due to the difference in geometry of the frontal part of nasal cavity, the flow near nares shows the difference.

• Journal of Chest Surgery
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• v.9 no.1
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• pp.41-43
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• 1976

Primary tumors of trachea are rather uncommon, and few cases of direct surgical excision were reported in the literature. Recently we had the opportunity to see a patient with a benign obstructing tumor of the trachea which was confirmed as fibroma. The patient has complained of intermittent dyspnea, especially during inspiratory phase, dry cough and wheezing of a strident character for last 8 years. Bronchoscopy or bronchography were not attempted because of severe dyspnea. Trachea tomogram revealed oval mass at the terminal trachea. The right posterolateral thoracotomy was performed. Tumor, $2.5{\times}1.7cm$ in size, was located at terminal trachea and removed through right lateral tracheotomy without difficulty. Postoperatively all the symptoms and signs disappeared.

• The Journal of the Korean dental association
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• v.36 no.2 s.345
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• pp.135-143
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• 1998

Cephalogram is one of the most important tool in researching growth and development of craniofacial area, orthodontic diagnosis and treatment planning. But its inherent distortion of actual length and angles during projecting three dimensional object to two dimensional plane might cause errors in quantitative analysis of shape and size. three dimensional high quality images can be obtained using computerized tomogram and have reported in literatures. Considering its expenses and amount of exposure to radiation, limitations still remain to be solved in its application to routine practice. construction of three dimensional image using principle of orientator can be obtained by biplanar stereoradiography. Theoretically two images, lateral and P-A can be used to construct three dimensional image provided that those are taken at same time by two different focal spots. As two images(lateral and P-A) obtained by conventional cephalogram have different head posture, those need compensation to construct three dimensional images. This study introduced principle of computerized head posture compensation and showed that conventional cephalogram could be used to construct three dimensional image and could be applied to routine orthodontic practice.