• Journal of KIISE:Computer Systems and Theory
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• v.27 no.3
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• pp.235-244
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• 2000

This paper addresses a new method for constructing surface representation of 3D structures from a sequence of tomographic cross-sectional images, Firstly, we propose cell-boundary representation by transforming the cuberille space into cell space. A cell-boundary representation consists of a set of boundary cells with their 1-voxel configurations, and can compactly describe binary volumetric data. Secondly, to produce external surface from the cell-boundary representation, we define 19 modeling primitives (MP) including volumetric, planar and linear groups. Surface polygons are created from those modeling primitives using a simple table look-up operation. Comparing with previous method such as Marching Cube or PVP algorithm, our method is robust and does not make any crack in resulting surface model. Hardware implementation is expected to be easy because our algorithm is simple(scan-line), efficient and guarantees data locality in computation time.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.05
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• pp.141-144
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• 1997

Femoral neck anteversion is the angle between the neck and the knee axis projected on a plane perpendicular to the longitudinal axis. Conventional methods that use cross-sectional Computed Tomography(CT) images to estimate femoral anteversion have several problems because of the complex 3D structure of the femur. These are the ambiguity of defining the longitudinal axis, the femoral neck axis and condylar line, and the dependence on patient positioning. Especially the femoral neck axis that is known as a major source of error is hard to determine from a single or multiple 2D transverse images. So we developed a new method for measuring femoral anteversion by 3D modeling method. In this method, femoral head is modeled as a sphere. The center of femoral neck is the mid-point of the 2D reconstructed oblique image in the femoral neck part. Then neck axis is a line connecting foregoing two centers. We model the longitude of femur as a cylinder, and the long axis is defined from the fitted cylinder. The knee axis which is tangent to the back of the femoral condyles is easily determined by table-top method. By the definition of femoral anteversion, the femoral anteversion is easily calculated from this model.

• Journal of the Optical Society of Korea
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• v.19 no.1
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• pp.69-73
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• 2015

The mesothelium is an essential lining for maintaining the normal homeostasis of the closed body cavity and a central component of pathophysiologic processes. The mesothelium has been known as the end target for asbestos which induces asbestos-related lung diseases. Malignant mesothelioma (MM) is a rare and fatal neoplasm predominantly due to asbestos exposure. Adaptation of an advanced and reliable technology is necessary for early detection of MM because it is difficult to diagnose this disease in its early stages. Optical coherence tomography (OCT) provides cross-sectional images of micro-tissue structures with a resolution of $2-10{\mu}m$ that can image the mesothelium with a thickness of ${\sim}100{\mu}m$ and, therefore, enable investigation of early development of MM. The mesothelium is typically located at the pleura and tunica vaginalis of the scrotum. In this study, we developed animal window models in the above two anatomical sites to visualize mesothelial layers within the mesothelium. OCT images at the two locations were also acquired.

• Journal of Dental Rehabilitation and Applied Science
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• v.19 no.1
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• pp.7-15
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• 2003

This study used FEM(Finite Element method) based on micro-CT images to see the effects of occlusal force distribution with varying bone density and structure. the mandibular premolar region from human cadaver, thickness of 10mm was imaged using micro-CT. the cross sectional images were taken every $10{\mu}m$. these were reconstructed and the longitudinal image at the mid point of mesiodistal of the speciman was obtained for the specimen for the FEM. The stress disribution produced by a vertical force at 100N and 100N horizontal were analyzed by MSC Nastran FEM Package. according to the result of this study the occlusal force distribution depends on the structure of cancellus bone and for further information on the occlusal force distribution on the tooth and the surrounding structure requires further studies on cancellus bone structure. CEJ of all model show the highest peak and region whice meet teeth and bone show second high peak. Original model and cortical bone add model show different stress distribution. Stress distribution changed according to bone structures and densities.

• Journal of East-West Nursing Research
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• v.17 no.1
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• pp.9-15
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• 2011

Purpose: The purpose of this study was to investigate recognition and knowledge regarding clinical trials, in particular, after a clinical trial education program (CTEP) among student nurses. Methods: A cross-sectional survey design of 215 student nurses at a university in Seoul was used with structured questionnaires. Results: Respondents had a high level of need for clinical trial and moderate levels in favorable image, safety, and need for education regarding clinical trial. The respondents who had participated in the CTEP felt the clinical trial more favorable and safer than those who did not. However, there were no significant differences in necessity of clinical trials and need for education regarding clinical trial between the CTEP participation and no participation groups. Respondents had a high level of knowledge about clinical trial, even though half of the respondents misunderstood that the physician can convince the subject to participate in clinical trial. There was no significant difference in knowledge level between groups. One third of the respondents had an intention to work in the area related to clinical trial because of aptitude or future prospect. Conclusion: The results of this study demonstrated that the CTEP might have an effect on student nurses' recognition rather than knowledge. The CTEP should be therefore developed targeting specific areas of misconceptions and recognition changes.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.4
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• pp.1677-1684
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• 2016

Background: Among the factors reported to determine the quality of life of breast cancer patients are socio-demographic background, clinical stage, type of treatment received, and the duration since diagnosis. Objective: The objective of this study was to determine the quality of life (QOL) scores among breast cancer patients at a Malaysian public hospital. Materials and Methods: This cross-sectional study of breast cancer patients was conducted between March to June 2013. QOL scores were determined using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30) and its breast cancer supplementary measure (QLQ-BR23). Both the QLQ-C30 and QLQ-BR23 assess items from functional and symptom scales. The QLQ-C30 in addition also measures the Global Health Status (GHS). Systematic random sampling was used to recruit patients. Results: 223 breast cancer patients were recruited with a response rate of 92.1%. The mean age of the patients was 52.4 years (95% CI = 51.0, 53.7, SD=10.3). Majority of respondents are Malays (60.5%), followed by Chinese (19.3%), Indians (18.4%), and others (1.8%). More than 50% of respondents are at stage III and stage IV of malignancy. The mean Global Health Status was 65.7 (SD = 21.4). From the QLQ-C30, the mean score in the functioning scale was highest for 'cognitive functioning' (84.1, SD=18.0), while the mean score in the symptom scale was highest for 'financial difficulties' (40.1, SD=31.6). From the QLQ-BR23, the mean score for functioning scale was highest for 'body image' (80.0, SD=24.6) while the mean score in the symptom scale was highest for 'upset by hair loss' (36.2, SD=29.4). Two significant predictors for Global Health Status were age and employment. The predictors explained 10.6% of the variation of global health status ($R^2=0.106$). Conclusions: Age and employment were found to be significant predictors for Global Health Status (GHS). The Quality of Life among breast cancer patients reflected by the GHS improves as age and employment increases.

• The Journal of the Korea Contents Association
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• v.11 no.10
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• pp.488-493
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• 2011

The Korean spine geometry and property data for researchers were made by KISTI and Catholic Institute for Applied Anatomy. We took whole spine CT, X-Ray, BMD scan for making high resolution cross-sectional spine images using more 20 donated cadavers(60 - 80 years). Then we constructed 3-dimensional volume model using serial CT images by Mimics software. The major morphometric parameters of vertebrae were measured. Mechanical motion and property data were obtained by the same cadavers using the DEXA for BMD and the spine simulator. The Korean spine geometry and property data could be used for research and development of medical device.

• Journal of the Korean Society for Nondestructive Testing
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• v.24 no.6
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• pp.581-589
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• 2004

In this study, the capacitive micromachined ultrasonic transducer(cMUT) was developed based on the previous research results. The cross sectional image of the developed cMUT was characterized. To measure the membrane displacement of the cMUT, the Michelson phase modulation fiber interferometer was constructed. The measured membrane displacement was in good agreement with the result of the finite element analysis. To estimate the ultrasonic wave generated by the cMUT, an ultrasonic system including a pulser, receiver and charge amplifier was used. The cMUT developed in this study shows a good performance and hence will be widely used in the non-contact ultrasonic applications.

• Journal of the Korean institute of surface engineering
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• v.49 no.5
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• pp.423-430
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• 2016

In this study, we investigated the corrosion damage characteristics of steel for offshore wind turbine tower substructure using an accelerated electrochemical test. The galvanostatic corrosion test method was employed with a conventional 3 electrode cell in natural sea water, and the steel specimen was served as a working electrode to induce corrosion in an accelerated manner. Surface and cross-sectional image of the damaged area were obtained by optical microscope and scanning electron microscope. The weight of the specimens was measured to determine the gravimetric change before and after corrosion test. The result revealed that the steel tended to suffer uniform corrosion rather than localized corrosion due to active dissolution reaction under the constant current regime. With increasing galvanostatic current density, the damage depth and surface roughness of surface was increased, showing approximately 25 times difference in damage depth between the lowest current density ($1mA/cm^2$) and the highest current density ($200mA/cm^2$). The gravimetric observation showed that the weight loss was proportionally increased with increment of current density that has 75 times different according by experimental conditions. Consequently, uniform corrosion of the steel specimen was conveniently induced by the electrochemically accelerated corrosion technique, and it was possible to control the extent of the corrosion damage by varying the current density.

• Restorative Dentistry and Endodontics
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• v.28 no.1
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• pp.41-49
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• 2003

There are increasing usage of Nickel-Titanium rotary files in modern clinical endodontic treatment because it is effective and faster than hand filing due to reduced step. This study was conducted to evaluate the effect of canal preparations using 3 different rotary Nickel-Titanium files that has different cross sectional shape and taper on the maintenance of canal curvature. Simulated resin block were instrumented with Profile(Dentsply, USA), GT rotary files(Dentsply, USA), Hero 642(Micro-Mega France), and Pro-Taper(Dentsply, USA). The image of Pre-instrumentation and Post-instrumentation were acquired using digital camera and overspreaded in the computer. Then the total differences of canal diameter, deviation at the outer portion of curvature, deviation at the inner portion of curvature, movement of center of the canal and the centering ratio at the pre-determined level from the apex were measured. Results were statistically analyzed by means of ANOVA, followed by Scheffe test at a significance level of 0.05. The results were as follows； 1. Deviation at the outer portion of curvature, deviation at the inner portion of curvature were showed largest in Pro-Taper so also did in the total differences of canal diameter(p＜0.05). 2. All the groups showed movements of center Profile combined with GT rotary files and Hero 642 has no difference but Pro-Taper showed the most deviation(p＜0.05). 3. At the 1, 2, 3mm level from the apex movements of center directed toward the outer portion of curvature, but in 4, 5 mm level directed toward the inner portion of curvature(p＜0.05). As a results of this study, it could be concluded that combined use of other Nickel-Titanium rotary files is strongly recommended when use Pro-Taper file because it could be remove too much canal structure and also made more deviation of canal curvature than others.