• 한국지반공학회논문집
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• 제20권9호
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• pp.155-166
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• 2004

국내 연약지반 활용을 위한 효율적이고 경제적인 안정처리 공법의 선정과 설계 및 시공을 위해서는 대상지반의 특성을 파악하는 것이 대단히 중요하다. 본 연구는 시화지구 연약점토의 물리적, 역학적 특성과 광물학적 특성을 파악하여 연약점토의 물리적, 역학적 특성과 광물학적 특성과의 상관관계를 알아보는 데 그 목적이 있다. 본 연구에서 는 연약점토의 광물학적 특성을 파악하기 위하여 X선 형광분석, X선 회절분석, 주사전자현미경분석과 에너지분산미분석 실험을 실시하였으며 시화지구 연약지반의 시추조사결과, 실내시험 및 현장시험결과와의 상관관계를 알아보았다. 또한 시화지구 연약점토의 특성을 양산과 군산 지역 연약점토의 특성과 비교하였다.

• 대한공간정보학회지
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• 제18권2호
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• pp.55-61
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• 2010

본 연구는 지상라이다로부터 획득한 3차원 점 데이터를 이용하여 구축된 공간자료를 격자(gridded) 및 비격자(un-gridded)로 구분하여 모델링을 실시하였고, 이러한 모델링 결과를 이용하여 가시선 분석 실험을 실시하였다. 두 모델의 형태에 따른 가시선 분석 결과를 비교하기 위하여 본 연구에서는 실험지역의 가시선 최대 도달거리를 A지역 30m, B지역 40m, C지역 50m로 구분하였고, 가시선 분석 소요 시간과 가시되는 점의 개수를 측정하였다. 실험 결과를 살펴보면, 비격자모델의 경우, 격자모델에 비해 지역별로 A지역은 약 3.9배, B지역은 약 5.4배, C지역은 약 6.5배 정도 많은 시간이 가시선 분석에 소요되었으며, A지역은 약 0.97배, B지역은 약 0.93배, C지역은 약 0.94배 정도 적은 가시점 개수가 측정되었다. 가시선 분석 소요시간은 가시선의 최대도달거리가 증가함에 따라 격자모델과 비격자 모델의 차이가 증가함을 알 수 있고, 반면에 가시되는 점의 개수는 가시반경의 크기에 크게 영향을 받지 않았다.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2007년도 춘계학술발표회 논문집
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• pp.243-248
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• 2007

This study proposed a procedure to improve the error defection of attached cadastral maps using digital map data. In addition, this study also provided the direction for the accuracy improvement of attached cadastral maps by comparing analysis methods. - such as centroid, Lee Sallee shape index, and area index. The analysis is performed as follows. First, by using centroid measurement, the center point of cadastral maps and attached cadastral maps are compared. Secondly by using Lee Sallee shape measurement, the location accuracy of range area is investigated. Thirdly, by using area measurement, the range area within allowable error scope is verified. Based on analysis, the discrepancy between cadastral maps and the attacked cadastral maps are detected as follows; 98.2% from Lee Sallee shape index, 41.8% from centroid, 15.4% from area index in the whole error.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 춘계 학술발표회 초청강연 및 논문집
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• pp.1036-1041
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• 2008

In order to analysis the reason of sliding failure in embankment slope under construction in soft soil area, a model section located in Gimhae Region in Gyeongsangnam-Do, where the sliding failure had been occurred during embankment works in soft soil area, had been selected. This area had been firstly treated with the Pack Drain Method, and additional embankment works of 9.7 meters out of total 14 meters in thickness had been under construction. The results of analysis showed that the reason of sliding failure were overspeed in embankment construction and the overestimation of design factors in calculating strength of each layer of embankment and poor management and inaccuracy reading of measurement devices.

• Journal of the Korean Wood Science and Technology
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• 제26권2호
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• pp.29-37
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• 1998

An image analysis program with the function of measuring various quantitative characteristics in the transverse surface of wood was developed using Delphi 2.0. Data on pore characteristics (conditions for image processing, proportion of pores in relationship to other elements, tangential diameter, area, tangential and radial diameter, x and y coordinates of pore center, and geometric coefficients) were saved in text file format. In addition, the pore area histogram in the tangential and radial directions was saved as a BMP (bitmap) type file. Analyses indicated that quantitative characteristics such as the relative radial distribution of pores in a growth ring, pore tangential area histogram, and proportion of pore in lumen area appear to be useful in separating four diffuse-porous woods and four ring-porous woods on the species level.

• 대한공간정보학회지
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• 제18권1호
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• pp.83-88
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• 2010

본 논문은 수도권 내 지역을 도시적 특성에 따라 군집 분석하여 수도권의 지역유형을 구분하고 그 특성을 파악하고자 하였다. 수도권 도시의 유형화를 위해 2005년을 시점으로 도시의 구성요소인 인구, 활동, 토지 및 시설을 나타내는 지표 10가지를 선정하였으며, 주성분분석을 통해 변수들의 공통된 특성이나 유사한 성질에 따라 공통인자를 추출하였다. 추출된 인자에 대한 인자득점을 이용하여 군집분석을 행하였고, 군집분석의 방법은 계층적 군집방법인 최단연결법, 최장연결법, 평균연결법, 와드법을 이용하였다. 그 결과 수도권을 5개의 군집으로 유형화 할 수 있었다.

• 대한치과기공학회지
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• 제27권1호
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• pp.27-39
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• 2005

This study is to show the qualitative analytic methods of facial asymmetry with three-dimensional morphometry and find out asymmetry change resulted from enlarging three local regions. Steel balls (1.2mm in diameter) were attached in twenty seven landmarks of a symmetrical artificial human skull. This artificial human skull was used as experimental materials. Twelve different asymmetrical artificial human skulls were formed by gradually enlarging the mandibular body length, gonial angle, and ramus height of the left hemiface. From the three-dimensional morphometry of each skull type, nine local area measurements and three total sum area measurements(representing the mandibular area, maxillary area, and lower facial area) were acquired and made into the surface area asymmetry degree. Menton deviation itself was used as the surface area asymmetry degree while right-left percentages were used in the other measurements. These surface area asymmetry degrees were compared with each other to find out asymmetry change according to the degree of actual facial asymmetry. Through the statistical analysis, following results were obtained. The results were as follows: 1. Left maxillary area of artificial human skull was 7.13$\pm$0.26% larger while mandibular area was 4.14$\pm$0.12% smaller than each those of right hemiface. After all, left lower facial area was 1.44$\pm$0.07% larger than those of right hemiface.(n=7). 2. Among the reduce rates of surface area asymmetry degree resulted from enlarging three local regions, ramus height was similar to mandibular body length while it was bigger than those of gonial angle. 3. Among the increase rates of menton deviation resulted from enlarging the local regions, ramus height was the biggest, mandibular body length was the second and gonial angle was the smallest. These results suggest that three-dimensional morphometry can be used to qualitatively analyse facial asymmetry and the asymmetry degree is more influenced by enlarging the ramus height, mandibular body length than those of gonial angle.

• Imaging Science in Dentistry
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• 제31권1호
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• pp.35-42
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• 2001

Purpose: To evaluate the usefulness of fractal analysis for diagnosis of periodontitis. Materials and Methods : Each 30 cases of periapical films of male mandibular molar were selected in normal group and patient group which had complete furcation involvement. They were digitized at 300 dpi, 256 gray levels and saved with gif format. Rectangular ROIs (10×20 pixel) were selected at furcation, interdental crest, and interdental middle 1/3 area. Fractal dimensions were calculated three times at each area by mass radius method and were determined using a mean of three measurements. We compared fractal dimensions at furcation and interdental crest area of normal group with those of patient group. And then we compared ratio of fractal dimensions at furcation area, interdental crest area to interdental middle 1/3 area. Results: Fractal dimension at interdental crest area of normal group was 1.979±0.018 and that of patient group 1.971±0.012 (p>0.05). Fractal dimension at furcation area of normal group was 1.986±0.024 and that of patient group 1.974±0.015 (p<0.05). The ratio of fractal dimension at interdental crest area to interdental middle 1/3 of normal group was 1.003±0.015 and that of patient group 0.993±0.018 (p<0.05). The ratio of fractal dimension at furcation area to interdental middle 1/3 of normal group was 1.006±0.018 and that of patient group 0.994±0.018 (p<0.05). Conclusion : The ratio of fractal dimension at interdental crest and furcation area to interdental middle 1/3 area showed a statistically significant difference between normal and patient group. In conclusion, it is thought that fractal analysis might be useful for the diagnosis of periodontitis.

• Asian Pacific Journal of Cancer Prevention
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• 제16권13호
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• pp.5573-5578
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• 2015

Background: A systematic review and meta-analysis were performed to compare the post-recurrence survival with hepatic re-resection versus transarterial chemoembolization (TACE) for recurrent hepatocellular carcinoma (HCC) after initial resection. Materials and Methods: All relevant papers were searched via PubMed, EMBASE, and Cochrane Library databases. Hazard ratios (HRs) with 95% confidence intervals (CIs) were pooled using a random-effects model. Subgroup analysis was performed according to country. Sensitivity analysis was performed in studies which clearly reported the recurrent regions, in moderate/high-quality studies, in studies published in full-text form, and in studies published after 2005. Results: In total, twelve papers were included in our study. Five and seven of them were of moderate- and poor-quality, respectively. The overall meta-analysis demonstrated a statistically significantly higher post-recurrence survival in the hepatic re-resection group than in those undergoing TACE (HR=0.64, 95%CI=0.52-0.79, P<0.0001). Heterogeneity was statistically significant and statistical significance remained in the subgroup analysis. Sensitivity analyses were also consistent with the overall analysis. Conclusions: Hepatic re-resection might provide a better post-recurrence survival than TACE for recurrent HCC after initial resection. However, considering the low quality of published studies and the potential bias of treatment selection, further randomized trials should be warranted to confirm these findings.

• 한국지리정보학회지
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• 제6권3호
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• pp.117-128
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• 2003

본 연구는 춘천시를 대상으로 수치표고모델, 토지이용 데이터 및 토지피복분류 데이터를 구축하고 이를 이용한 토지이용 CG(computer graphics)화상과 토지피복 CG화상의 작성과 가시권분석을 통해 광역적 도시경관의 특성을 파악하였다. 토지피복분석의 결과, 1989년에서 2000년까지 시가지는 $7.7km^2$ 증가하였으며, 녹지는 $12.7km^2$가 감소하였다. 용도지역상 시가지, 개발제한구역, 녹지지역 등에서 녹지의 감소와 시가지의 증가가 나타났다. 춘천시의 도시경관은 3개의 유형으로 대분할 수 있었다. 유형1은 개발제한구역을 중심으로 형성된 경관, 유형2는 자연녹지, 생산녹지 등의 녹지를 중심으로 한 경관, 그리고 유형3은 시가지와 수역을 중심으로 한 경관특성을 가지고 있었다. 토지피복 CG화상은 모든 유형에서 녹지의 감소와 시가지의 증가가 나타났다. 가시권 분석의 결과, 경관적 중요도가 높은 영역에서도 녹지감소의 경향이 동일하게 나타나 이 영역에서 녹지경관의 보전 및 관리가 요구되었다.