• Journal of radiological science and technology
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• v.8 no.2
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• pp.11-14
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• 1985

The author came to analize and get the following problems after researched radiographic quality in order to find out the necessary factors to improve in radiographs of frontal projection of the chest selected at random of the adult patients (1545 male, 1520 female) who had been examined in 4 departments of radiology of the general hospitals in Seoul and Kyungki area. 1. Problems of x-ray film or of radiographic cassette appeared in 2.97% radiographs on account of selection of the film size (except costophrenic sinus) (1.79%), poor screen-film contact (0.85%), light leakage of cassette (0,33%). 2. Problems of patients' positioning or breathing appeared in 16.57% radiographs of all because of overlapping of lung apex and clavicle (6.98%), overlapping of scapula and lung field (5.87%), asymmetrical projection of clavicles (1.76%), errors in positioning and breathing of the patient (1.96%). 3. Problems of x-ray exposure factors or film processing appeared in 22.25% radiographs because of over-density (2.64%), under-density (3.95%), fog (0.59%), demonstration density under clavicles or lung marking unsharply (3.82%), not clear of lung marking from breast region (0.94%), not clear the lung marking from the part overlapped of heart and lungs (3.92%), not clear the lung marking from the part overlapped of liver and lung (6.49%).

• Journal of the Korean Society for Precision Engineering
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• v.28 no.12
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• pp.1353-1358
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• 2011

LAT(Laser Assisted Turning) is a method that applies a machining process after softening a workpiece in which a preheating process is locally applied to its machining section using laser heat source. LAT shows several advantages, such as high productivity, reduction of manufacturing cost, high quality. Analysis of temperature distribution after preheating for LAT is very difficult due to its very small heat input area and large energy and its movement. Also, the LAT for a square bar is more difficult because the shape of a laser heat source can be changed according to the rotation of the workpiece. In this study, thermal analysis for LAT of square bar was performed using laser heat source projection method. And, the analysis results were compared with the results of the prior study of numerical calculation method. It is thus shown that the proposed method is efficient for the thermal analysis of a shaped bar.

• Journal of Technologic Dentistry
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• v.41 no.1
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• pp.9-19
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• 2019

Purpose: This study was conducted to comparative evaluate the marginal and internal gap of three-unit metal frameworks(Co-Cr) fabricated by wax milling method and digital light projection method of CAD/CAM systems. Methods: All the specimens were fabricated by three different fabrication methods: conventional wax up with casting(CWC), milled wax block with casting(MWC), digital light projection with casting(DLPC) (n=10 each). The marginal and internal fits of specimens were examined using a replica technique. The light-body silicone thickness was measured at 8 reference points(each abutment: 16 measurements). All measurements were conducted by a stereomicroscope. Digital photo were taken at $150{\times}$ magnification and then analyzed using a measurement software. The Mann-Whitney test was used for analyzing the results. Results: Statistically significant differences were found between the fabrication methods(p<0.001). The mean(SD) is ${\mu}m$ for fabrication methods, the mean marginal fit were recorded respectively, CWC 63(38), MWC group 50(33), DLPC 103(54) and the mean internal fit CWC 96(47), MWC group 116(41), DLPC 138(66). Conclusion : The marginal and internal fit were statistically different according to the fabrication methods(p<0.001). In all fabrication methods, the greatest misfit was found the occlusal area of all specimens.

• Journal of Broadcast Engineering
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• v.12 no.2
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• pp.137-147
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• 2007

Projection-based augmented reality (AR) system refers to the system that accurately project high quality virtual information at the user-specified area by using the projector. Most of projection-based AR systems use the display device to support high quality and wide screen for increasing the user-immersion. Furthermore, they are implemented on the desktop environment due to the computational complexity. However, these projection-based AR systems are not suited as a mobile system and thus it may be inconvenient in the user point of view. Fortunately, Miniaturization of projectors and improved capacity of the mobile processor allowed the mobile AR system to be convenient. The limitation of established mobile AR system is that it uses small display screen which does not support high-resolutions and thus it may reduce the user-immersion into the system. In this paper, we propose portable projection-based display system, which overcomes the limitations of both projection-based and mobile-based AR systems. We have conducted the user evaluation to verify the effectiveness and the utmost capacity of the system.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.651-652
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• 2011

• Archives of Plastic Surgery
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• v.34 no.4
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• pp.490-492
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• 2007

Purpose: Nipple reconstruction is an important step in breast reconstruction after mastectomy. There are considerable number of reconstructive methods developed over the past years. Each of these has not only its own special advantages, but also limitations. Therefore, no single method has become the overwhelming favorite. Sometimes it seems to be compromised when the nipple must be located directly over a linear scar. Methods: A 48-year-old female patient received a central lumpectomy with circumareolar resection of the nipple areolar complex 4 months ago. The newly designed nipple must be positioned directly astride a scar. We drew two equal-sized rectangular flaps sharing a common limb on a transverse scar and the result was two opposing plow form. Each flap size was about 1.3 cm wide and 2.5 cm long. First we elevated the flap from the distal part at a deep dermal plane, then deepened the level of dissection to raise the dermal-fat flaps. The donor site could be closed directly without any dog-ear deformity. Then we folded down the elevated flaps and loosely sutured skin with nonabsorbable materials. Each flap inner side was approximated side by side. Finally we made new natural nipple with 6 mm projection. We applied tattooing in the areola area with micropigmentation device after three months. Results: After ten months of follow-up periods, the nipple projection was stable and symmetric. The nipple projection was 3.1 mm, compared with 2.8 mm for the opposite nipple. Conclusion: Our experiences shows that this double opposing plow flap is a particularly useful and simple technique when there is a traverse scar crossing the center of the proposed nipple area.

• Journal of Korea Multimedia Society
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• v.6 no.2
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• pp.230-239
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• 2003

This paper presents face recognition algorithm using projection vector reflecting local feature for the area in contour lines. The outline shape of a face has many difficulties to distinguish people because human has similar face shape. For 3 dimensional(3D) face images include depth information, we can extract different face shapes from the nose tip using some depth values for a face image. In this thesis deals with 3D face image, because the extraction of contour lines from 2 dimensional face images is hard work. After finding nose tip, we extract two areas in the contour lilies from some depth values from 3D face image which is obtained by 3D laser scanner. And we propose a method of projection vector to localize the characteristics of image and reduce the number of index data in database. Euclidean distance is used to compare of similarity between two images. Proposed algorithm can be made recognition rate of 94.3% for face shapes using depth information.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.365-365
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• 2000

In this paper, we describe the system to recognize the six digit postal number of mails using neural network. Our zip-code recognition system consists of a preprocessing procedure for the original captured image, a segmentation procedure for separating an address block area with a shape, and recognition procedure for the cognition of a postal number. we extract the feature vectors that are the input of a neural network for the recognition process based on an area optimizing and an image thinning processing. The neural network classifies the zip-code in the mail and the recognized zip-code is verified through the zip-code database.

• Journal of Korean Academy of Nursing Administration
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• v.8 no.4
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• pp.615-632
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• 2002

Purpose : this study was to project demand of home nursing care in Korea for contributing toward the distribution of home nursing care resource. Method : demand of home nursing care is projected according to income level and needed service level of each person. in addition, demand sufficiency of home nursing care is taken by estimating for supply level available. Result : home nursing care service is scarecely provided to people who belong to second area, that is, only $1.6{\sim}2.3%$ out of them are provided and also, supply system comes short of meeting demand of the other people(who belong to one, third area). Conclusion : therefore, for proper provision of home nursing care, different supply system and policy direction for establishment and expansion of home nursing care is to be developed.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.11 no.2
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• pp.55-65
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• 2008

This study was surveyed to analyze vegetation structure of mountainous wetlands in Chung-ju city and around area from September to November, 2006. 6 sites of total 15 potential mountainous wetlands were discriminated throughout field survey. By classification system of mountainous wetlands presented in manual of forest wetlands research, types of wetlands were classified into slant and a flat. Many sites were covered with land plants as Pueraria thunbergiana and so on. To understand vegetation structure of mountainous wetlands, Height, DBH (diameter at breast height), DI (Dominance Index), Sociability and Constancy were surveyed and Based on this result, a projection chart was drawn. As results, Salix koreensis in tree layer and Persicaria thunbergii and Impatiens textori in herb layer were surveyed as broadly distributed species. This study is mainly focused on vegetation condition of mountainous wetlands. But, it will be needed studying on classification system of mountainous wetland type and functional assessment for conservation or management of wetlands.