• 대한공간정보학회지
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• 제23권4호
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• pp.17-24
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• 2015

본 연구에서는 춘천지역을 대상으로 집중호우에 의해 발생된 산사태 및 토석류에 대한 분석을 위해 고해상도 디지털항공사진영상과 항공 LiDAR 자료를 이용하여 생성된 고품질 3차원 공간정보를 활용하였다. 또한 산사태 발생 지역에 대한 기존 산사태 위험등급도와 산사태 관련인자의 연관성을 분석하였으며 집중호우에 의해 토석류를 동반한 산사태 피해가 많이 발생된 지역을 대상으로 토석류의 분석결과를 검토하였다. 이 결과를 이용하여 기존의 산사태 위험지도를 효과적으로 갱신하고 산사태 위험지역에 대한 관리에 고품질 공간정보를 활용할 수 있는 방안을 제시하고자 하였다.

• 한국산림과학회지
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• 제95권3호
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• pp.240-249
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• 2006

최근, 소나무재선충(Bursaphelenchus xylophilus)에 의한 소나무림의 피해에 대한 사회적 심각성이 크게 대두되고 있다. 소나무 재선충에 의한 산림피해는 피해지 내에서는 매개충인 솔수염하늘소의 자연적인 영역확장에 의해 확산되는 반면, 전국적으로는 감염목의 인위적 반출 및 이동에 의해 확산이 진행되고 있다. 본 연구에서는 부산 대변항의 재선충 피해지내에서 항공사진 및 현지조사에 의해 피해목의 공간적인 위치를 파악하였고, 공간통계학적인 방법을 통하여 피해목의 공간분포유형, 피해발생과 지형인자간의 관계를 분석하였다. 또한, 지형공간자료를 통계학적 Tree 모형에 적용한 CART(Classification and Regression Trees)모형을 이용하여 재선충 피해의 자연적인 확산 예측 지도를 작성하였다. 본 연구를 통해 공간통계학적인 분석과 CART모형이 소나무재선충 피해의 공간분포 및 자연적 확산유형을 파악하는데 유용한 도구로 활용될 수 있음을 확인할 수 있었다.

• 보존과학회지
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• 제27권3호
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• pp.251-260
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• 2011

이 연구에서는 석조문화유산의 손상유형별 표준범례를 제시하고, 손상지도 작성방법에 대한 공정시스템을 구축하였으며, 균열지수 개발과 표면 및 3차원 손상율 평가기법을 제시하였다. 손상유형별 표준범례는 균열, 박리, 박락, 탈락, 입상분해 및 공동으로 세분한 다음 상용 그래픽 프로그램으로 제작하였으며, 손상지도는 손상 영역에 대한 정확도와 신뢰도를 높이기 위해 3차원 디지털복원과 고해상도 사진맵핑 기술을 적용하였다. 또한 균열지수를 개발하여 대상 석조문화유산의 물리적 손상도에 대한 정량평가를 수행하였고, 가상복원 모델링을 통해 탈락부의 부피와 3차원 손상율을 산출하였다. 이를 통해 마곡사오층석탑의 손상도를 정량적으로 평가한 결과, 전체적으로 북측면이 구조상 균열(1.70), 미세균열(1.34), 박락(20.2%), 탈락(13.0%)의 손상점유율이 높게 나타났으며, 1층 옥개석의 3차원 손상율은 6.7%로 산출되었다.

• Journal of Periodontal and Implant Science
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• 제24권1호
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• pp.165-177
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• 1994

To investigate the depth of the root concavity and root surface area of the maxillary first premolar, 40 maxillary first premolars were used. All the teeth which extracted because of advanced periodontal disease and orthodontic treatment procedure, were sectioned every 1.5mm from cementoenameljunction to the apex with hard tissue microtome. Each sectioned root was taken photograph with slide film, and projected for measuring with a calibrated digital Curvi-Meter. The root surface area, percentage of the RSA and the linear variation of the RSA were calibrated for each 1.5mm section. Linear variation of the depth of root concavity was measured on mesial and distal root surface for each section using computer-aided digitizer. The results were as follows. 1. The total mean root length of maxillary first premolar was 13.48mm. Mean buccal root length of 2-rooted tooth was 12.59mm, mean palatal root length was 12.73mm, and mean root length of single rooted tooth was 13.78mm. 2. The total mean root surface area of maxillary first premolar was $194.17mm^2$, mean root surface area for 2-rooted tooth was $205.97mm^2$ and mean root surface area for single rooted tooth was $188.49mm^2$. 3. It was 59.93% of the total root surface area that the area from CEJ to coronal 6mm. And, the coronal half of the root length accounted for approximately 71.76% of the total root surface area. 4. Most deepest concavity of the mesial root surface was 0.65mm at apical 3.0mm, 4.5mm level in maxillary first premolar. And, that of the distal root surface was 0.37mm at apical 4.5mm level. 5. All of the maxillary first premolar had mesial root surface concavity. This mesial root surface concavity appeared to be more pronounced in 2-rooted tooth than single rooted tooth.

• Journal of Periodontal and Implant Science
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• 제43권4호
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• pp.160-167
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• 2013

Purpose: This study examined the factors that can be associated with the appearance of the interproximal papilla. Methods: One hundred and forty-seven healthy interproximal papillae between the maxillary central incisors were examined. For each subject, a digital photograph and periapical radiograph of the interdental embrasure were taken using a 1-mm grid metal piece. The following parameters were recorded: the amount of recession of the interproximal papilla, contact point-bone crest distance, contact point-cemento-enamel junction (CEJ) distance, CEJ-bone crest distance, inter-radicular distance, tooth shape, embrasure space size, interproximal contact area, gingival biotype, papilla height, and papilla tip form. Results: The amount of recession of the interproximal papilla was associated with the following: 1) increase in contact point-bone crest, contact point-CEJ, and CEJ-bone crest distance; 2) increase in the inter-radicular distance; 3) triangular tooth shape; 4) decrease in the interproximal contact area length; 5) increase in the embrasure space size; and 6) flat papilla tip form. On the other hand, the amount of gingival recession was not associated with the gingival biotype or papilla height. In the triangular tooth shape, the contact point-bone crest distance and inter-radicular distance were longer, the interproximal contact area length was shorter, and the embrasure space size was larger. The papilla tip form became flatter with increasing inter-radicular distance and CEJ-bone crest distance. Conclusions: The relative position of the interproximal papilla in healthy subjects was associated with the multiple factors and each factor was related to the others. A triangular tooth shape carries a higher risk of recession of the interproximal papilla because the proximal contact point is positioned more incisally and the bone crest is positioned more apically. This results in an increase in recession of the interproximal papilla and flat papilla tip form.

• Archives of Plastic Surgery
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• 제36권5호
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• pp.654-659
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• 2009

Purpose: A botulinum toxin type A (BoNT - A) injection has been used as a noninvasive management for lower face contouring since 2000. The aim of this study was to compare reduction rate of lower face width for a longtime according to repeated Botox$^{(R)}$ injections on masseter muscles for lower face contouring procedure. Methods: Forty - five patients were analyzed for single session of Botox$^{(R)}$ injection and 13 patients were evaluated for repeated Botox$^{(R)}$ injections for over two years. Single injection group was tracked regular intervals at 1, 3, 6, 10, 12 months after injection, and repeated injection group was measured at every injection time. Twenty - five to thirty units of Botox$^{(R)}$ was injected into each masseteric muscle at five to six points at the prominent portions of the mandibular angle. Standardized frontal view of digital photographs were analyzed by Adobe Photoshop$^{(R)}$ (version CS3) to measure an reduction rate of lower face width. Results: Reduction rate was 3.7%, 6.9%, 6.2%, 4%, 4% at 1, 3, 6, 10, 12 months post injection each other in single injection group. However, more than 8% reduction rate was found in repeated injection group persistently for more than two years. Conclusion: This study shows that effective duration of Botox$^{(R)}$ injection for lower face contouring is expected to continue over one year clinically. Moreover, repeated injections maintained lower reduction rate consistently for a long time. Therefore, repeated injections on masseter muscles at regular intervals are most effective procedure for lower face contouring.

• 대한기계학회논문집
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• 제12권5호
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• pp.1121-1129
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• 1988

본 연구에서는 oil-bath를 이용한 종래의 방법에 의해 얻어진 사진으로 부터 분무액적의 수와 크기를 자동적으로 측정하는 방법을 시도하였다.특히 측정을 효과 적으로 수행하기 위해 한 영상에서 비교적 맣은 분무액적을 측정하는 방법과 붙어있는 액적들이나 이물질 등을 걸러내는데 중점을 두었으며, 아울러 본 연구를 통하여 설정 된 측정방법의 정확도를 검토하였다.

• Nutrition Research and Practice
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• 제15권5호
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• pp.655-671
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• 2021

BACKGROUND/OBJECTIVES: While plate waste has been widely investigated in hospitals, there have been minimal studies specific to the texture-modified diet (TMD). This study aims to determine the percentage of plate waste among patients prescribed with TMD and its contributory factors. SUBJECTS/METHODS: This was a single-centre study conducted in the university hospital on three types of TMD (blended diet, mixed porridge, minced diet) during lunch and dinner meals. Weighing method and visual estimation method assisted by digital photograph were adopted in this study. Face to face interview was carried out to investigate on 1) the food/food service quality factors in terms of patients' satisfaction level towards sensorial quality of food and food services provided and 2) the clinical/external factors including appetite, the provision of oral nutrition support, time taking the diet, the need for feeding assistance and the length of hospital stay. RESULTS: The mean percentage of overall plate waste of 95 patients receiving TMD was high (47.5%). Blended diet was identified as the most wasted diet (65%) followed by minced diet (56%) and mixed porridge (35%). Satisfaction level among patients was moderate. Patients on TMD in general had higher satisfaction level on the aspect of food service as compared to food quality. Substantial association between sensorial qualities of food and plate waste were varied according to individual TMD type. A multiple linear regression showed that only the satisfaction level toward the aspects of appearance and variety of foods were the predictors of TMD plate waste (R² = 0.254, P < 0.05). CONCLUSIONS: A significant relationship between the percentage of plate waste and the overall satisfaction level of patients receiving TMD suggests that vigorous strategies are needed to reduce the food waste of TMD which will lead to a better nutritional status and clinical outcomes among the patients.

• 치위생과학회지
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• 제21권4호
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• pp.219-226
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• 2021

Background: Proper detection and management of dental plaque are essential for individual oral health. We aimed to evaluate the maturation level of dental plaque using a two-tone disclosing agent and to compare it with the fluorescence of dental plaque on the quantitative light-induced fluorescence (QLF) image to obtain primary data for the development of a new dental plaque scoring system. Methods: Twenty-eight subjects who consented to participate after understanding the purpose of the study were screened. The images of the anterior teeth were obtained using the QLF device. Subsequently, dental plaque was stained with a two-tone disclosing solution and a photograph was obtained with a digital single-lens reflex (DSLR) camera. The staining scores were assigned as follows: 0 for no staining, 1 for pink staining, and 2 for blue staining. The marked points on the DSLR images were selected for RGB color analysis. The relationship between dental plaque maturation and the red/green (R/G) ratio was evaluated using Spearman's rank correlation. Additionally, different red fluorescence values according to dental plaque accumulation were assessed using one-way analysis of variance followed by Scheffe's post-hoc test to identify statistically significant differences between the groups. Results: A comparison of the intensity of red fluorescence according to the maturation of the two-tone stained dental plaque confirmed that R/G ratio was higher in the QLF images with dental plaque maturation (p<0.001). Correlation analysis between the stained dental plaque and the red fluorescence intensity in the QLF image confirmed an excellent positive correlation (p<0.001). Conclusion: A new plaque scoring system can be developed based on the results of the present study. In addition, these study results may also help in dental plaque management in the clinical setting.

• Restorative Dentistry and Endodontics
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• 제46권2호
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• pp.23.1-23.11
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• 2021

Objectives: This study assessed the reliability of digital color measurements using images of resin composite specimens captured with a cellphone. Materials and Methods: The reference color of cylindrical specimens built-up with the use of resin composite (shades A1, A2, A3, and A4) was measured with a portable spectrophotometer (CIELab). Images of the specimens were obtained individually or pairwise (compared shades in the same photograph) under standardized parameters. The color of the specimens was measured in the images using RGB system and converted to CIELab system using image processing software. Whiteness index (WI_D) and color differences (ΔE₀₀) were calculated for each color measurement method. For the cellphone, the ΔE₀₀ was calculated between the pairs of shades in separate images and in the same image. Data were analyzed using 2-way repeated-measures analysis of variance (α = 0.05). Linear regression models were used to predict the reference ΔE₀₀ values of those calculated using color measured in the images. Results: Images captured with the cellphone resulted in different WI_D values from the spectrophotometer only for shades A3 and A4. No difference to the reference ΔE₀₀ was observed when individual images were used. In general, a similar ranking of ΔE₀₀ among resin composite shades was observed for all methods. Stronger correlation coefficients with the reference ΔE₀₀ were observed using individual than pairwise images. Conclusions: This study showed that the use of cellphone images to measure the color difference seems to be a feasible alternative providing outcomes similar to those obtained with the spectrophotometer.