• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.28 no.1
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• pp.27-36
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• 1998

The purpose of this study was to obtain information on the clinical and radiographic features of the fibro-osseous lesions in the jaws. For this study, the author examined and analysed the clinical records and radiographs of 71 cases of 68 patients in fibrous dysplasia, 35 cases of ossifying fibroma and 30 cases of 16 patients of periapical cemental dysplasia diagnosed by clinical and radiographic or histopathological examinations. The obtained results were as followings: L Fibrous dysplasia occurred most frequently in the 2nd decade (30.0％), ossifying fibroma in the 3rd-4th decades, periapical cemental dysplasia in the 4th decade, and all of three lesions showed slight predilection in females. In most cases, chief complaints were painless facial swelling in fibrous dysplasia and ossifying fibroma, and periapical cemental dysplasia was found accidentally in radiographs. 2. Fibrous dysplasia was occurred more frequently in maxilla, ossifying fibroma in mandible and both lesions in premolar-molar area. Periapical cemental dysplasia was occurred most frequently in the mandibular anterior area. The size of fibrous dysplasia was larger than that of ossifying fibroma, and the shape of ossifying fibroma was more round and elliptical than fibrous dysplasia whose was fusiform. 3. Fibrous dysplasia was shown homogeneous radiopaque shadow of 57.6％ and ossifying fibroma & periapical cemental dysplasia were shown mixed appearance of radiolucency and radiopacity shadows at 74.2％, 60.0％, respectively. 4. Fibrous dysplasia was entirely shown poorly defined at 87.7％, but ossifying fibroma & periapical cemental dysplasia were shown well outlined at 60.0％, 70.0％, respectively. 5. Cortical thinning and expansion were observed in fibrous dysplasia and ossifying fibroma, and severe in ossifying fibroma than fibrous dysplasia, and those signs were not seen in periapical cemental dysplasia. Loss of lamina dura was dominant in fibrous dysplasia and root resorption was dominant in ossifying fibroma. Displacement of mandibular canal and the degree of the increase of vertical dimension were alike in both lesions. Displacement of maxillary sinus or nasal cavity, thinning & expansion of the maxillary sinus were dominant in fibrous dysplasia. 6. Polyostotic fibrous dysplasia was occurred at 5.9％, Multiple periapical cemental dysplasia at 43.7％. Occurrence rate in the edentulous area of fibrous dysplasia and ossifying fibroma were 7.0％, 8.6％, respectively.

• Journal of Korean Society of Forest Science
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• v.78 no.4
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• pp.381-395
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• 1989

The main purpose of this research is to provide scientific informations about standard wage and performance tariffs in forest management with special reference to working time for thinning. To identify relationships between net working time and tree characteristics, three geographically different sample plots were established at Yangsan, Bongpyung and Jinan and 460 oaks, 372 Japanese larches, 232 red pine and 240 pitch pine mere selected at each sample plots. The results of statistical analysis using multiple regression are as follows ; 1. Five independent variables of breast height diameter(DBH), mid-diameter(MD) large end diameter(LD), log-length(L), No. of branches(NOB) were stable independent of worker and tree species. 2. Comparing correlation coefficient of five independent variables, the best predictive variables, breast height diameter and No. of branches, were selected. Breast height diameter and No. of branches were identified as the most important independent variables in terms of effect on the dependent variable of the working time. 3. Comparing coefficient of determination (Rp) and residual mean square (MSEp), the best Linear regression equation for each tree species was selected as follower : $WT=a+b1{\times}NOB+b2{\times}DBF$ 4. Proportion of hang-up time to total working time in thinning were 66% in oak stand, 74%, in Japanese larch stand, 55%, in red pine stand and 52% in pitch pine stand, respectively. 5. Based on the best regression equation, a table of working time was made by strata of number of branches and breast height diameter. 6. Total working time using the best regression equation in Table 5 can be predicted in terms of felling time, limbing time, hang-up time, i.e., total working time increases by 11 to 13 seconds with every 1 centimeter increase in breast height diameter from 7 to 16 centimeter.

• Childhood Kidney Diseases
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• v.19 no.2
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• pp.125-130
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• 2015

Introduction: This study investigated whether renal and bladder ultrasonography (RBUS) findings performed in children with the first incidence of febrile urinary tract infection (UTI) can predict UTI recurrence, high-grade vesicoureteral reflux (high-grade VUR), or acquired renal scarring (aRS). Methods: In all, 917 children who were admitted to our hospital from January 2001 to October 2010, owing to the first incidence of febrile UTI were enrolled in this study. All children underwent RBUS during admission. The mean follow-up was 7.9 months (standard deviation $[SD]{\pm}13.3$). UTI recurrence rates were calculated according to various clinical parameters. By using bivariate and multiple logistic regression analyses, we determined whether age, sex, abnormal RBUS findings, abnormal dimercaptosuccinic acid renal scan findings, or RBUS findings parameters were predictive of UTI recurrence, high-grade VUR, or aRS. Results: On RBUS, hydronephrosis and congenital anomaly of the kidney and urinary tract significantly predicted UTI recurrence. A small kidney, hydroureter, hydronephrosis, cortical thinning, and increased parenchymal echogenicity significantly predicted high-grade VUR. However, their odds ratios (OR) are low compared to normal RBUS findings (recurrent UTI: OR 0.432 and 0.354 vs. 0.934, respectively, high-grade VUR: .019, 0.329, 0.126, 0.058, and 0.188 vs. 2.082, respectively). No RBUS findings significantly predicted aRS. Recurrent UTI, high-grade VUR, and abnormal RBUS findings significantly predicted aRS (OR of 4.80, 4.61, and 2.58, respectively). Conclusion: RBUS is necessary to exclude severe congenital renal scarring, obstructive uropathy, and renal abscess at the first incidence of febrile UTI and is helpful in determining the need for subsequent clinical imaging.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.21 no.5
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• pp.81-96
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• 2018

The purpose of this study is to analyze the characteristics of vegetation changes and structures in the buffer green zone of Sihwa Industrial Complex and propose environmental, ecological and multi-functional vegetation management directions. The density of the Pinus thunbergii decreased from $23.1trees/100m^2$ in 2006 to $9.6trees/100m^2$ in 2017 due to the influence of thinning works. Its green volume increased from $0.97m^3/m^2$ to $2.02m^3/m^2$, contributing to the improvement of the atmospheric environment and promotion of biodiversity. The density of deciduous broad-leaved trees at the top maintained at $18{\sim}21trees/100m^2$. In the areas where the understory vegetation was removed, Pueraria lobata spread as an invasive plant and disturbed the forest. In the areas where the understory vegetation was not removed, various native plant species including the Rhus javanica and Celtis sinensis were introduced and contributed to the development of a forest in a multiple structure. There was a concern with the spread of Robinia pseudoacacia which developed into understory vegetation in Pinus thunbergii forest and some canopy forest. The study proposed vegetation management directions for the back, top and front side according to the physical structure of large-scale buffer green zone formed in a long linear form and the usage characteristics of adjacent land.

• Journal of the Korean Society of Radiology
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• v.2 no.1
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• pp.23-29
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• 2008

The present study proposed a method that dissolves ultrasonographic images into multiple resolutions using wavelet conversion and a boundary detection filter and improves the quality of ultrasonographic images through boundary detection filtering. In order to reduce noises and strengthen edges, the proposed method adjusted selectivity coefficient by area step by step from a low resolution image obtained from wavelet converted images to a high resolution image and performed edge filtering in consideration of direction. Through this method, we generated a selective low pass filtering effect in areas except edges by decreasing the wavelet coefficient for pixels in spot areas, improved continuity by smoothing edges in the tangential direction, and enhanced contrast by thinning in the normal direction. Through an experiment, we compared the filtering method using a non linear anisotropic expansion model and the filtering method using wavelet contraction structure in single resolution.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11b
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• pp.227-235
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• 2000

Agricultural products are easily deformable its shape because of some external forces. However, these force behavior is difficult to measure quantitatively. Until now, many researches on the mechanical property was performed with various methods such as material testing, chemical analysis and non-destructive methods. In order to investigate force behavior on the cellular unit of agricultural products, electro-microscope based 3D image processing method will contribute to analysis of plant cells behavior. Before image measurement of plant cells, plant sample was cut off cross-sectioned area in a size of almost 300-400 ${\mu}$ m units using the micron thickness device, and some of preprocessing procedure was performed with fixing and dyeing. However, the wall structure of plant cell is closely neighbor each other, it is necessary to separate its boundary pixel. Therefore, image merging and shrinking algorithm was adopted to avoid disconnection. After then, boundary pixel was traced through thinning algorithm. Each image from the electro-microscope has a information of x,y position and its height along the z axis cross sectioned image plane. 3D image was constructed using the continuous image combination. Major feature was acquired from a fault image and measured area, thickness of cell wall, shape and unit cell volume. The shape of plant cell was consist of multiple facet shape. Through this measured information, it is possible to construct for structure shape of unit plant cell. This micro unit image processing techniques will contribute to the filed of agricultural mechanical property and will use to construct unit cell model of each agricultural products and information of boundary will use for finite element analysis on unit cell image.

• Journal of Korean Society of Forest Science
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• v.88 no.4
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• pp.498-509
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• 1999

This study aims to clarify the effect of forest management practices(thinning and pruning) in forest hydrological processes on electrical conductivity to get the fundamental information on the facilitation of purifying water quality after forestry practices. Rainfall, throughfall, stemflow, soil and stream water were sampled at the study sites which consist of Abies holophylla and Pinus koraiensis in Kwangnung Experimental Forest for 6 months from March 1 to August 4, 1998. In case of deviding into forest hydrological processes, multiple regression equations of electrical conductivity and total amount of anion, $NO{_3}^-$ of throughfall, stemflow, soil water of management site in Abies holophylla shows high significance. And multiple regression equations of electrical conductivity and total amount of anion, $SO{_4}^{2-}$, $Cl^-$ of throughfall, stemflow, soil water of non-management site in Abies holophylla shows high significance. Multiple regression equations of electrical conductivity and $NO{_3}^-$, before non-rain days of throughfall, stemflow, soil water of management site in Pinus koraiensis shows high significance. And multiple regression equations of electrical conductivity and total amount of ion, $NO{_3}^-$, $K^+$, pH, total amount of anion of throughfall, stemflow, soil water of non-management site in Plinus koraiensis shows high significance. Multiple regression equations of electrical conductivity and pricipitation, total amount of ion, $Na^+$ of stream water in Abies holophylla and Pinus koraiensis shows high significance. In case of combining into forest hydrological processes, multiple regression equations of electrical conductivity and total amount of cation and anion, $Na^+$, $Cl^-$, and pH in rainfall, throughfall, stemflow, soil and stream water shows high significance.

• The korean journal of orthodontics
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• v.30 no.2 s.79
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• pp.185-196
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• 2000

Patients who want to reduce their lip protrusion usually estimate the severity of the lip protrusion on the frontal aspect. Most orthodontists have a perplexed experience of a reduced thin line of vermilion border on the frontal aspect as incisors we retracted, even though the lip protrusion is thought to be reduced favorably on the sagittal aspect. Some patients also look older after orthodontic treatment because of severe lip thinning. This unaesthetic reduction of vermilion border urges us to study the vertical lip change during orthodontic procedure. The purpose of this study was to evaluate the vertical lip and perioral soft tissue changes in respect to incisor retraction in an effort to analyze which factors might be responsible for their vertical changes, using the multiple regression analysis. The results were as follows. 1. Upper and lower lip philtrum length(SnLs, LiB') were increased after retraction of anterior teeth, where as upper and lower vermilion height(LsSuls, StmiLi), and vermilion length(LsLi) were decreased. 2. Upper and lower lip length(SnStms, StmiB'), and soft tissue lower anterior facial height(SnMe') did not show any significant difference after treatment. 3. The increase of the upper lip philtrum length was mainly influenced by the extrusion of upper anterior teeth(${\Delta}U1V$), and the increase of the lower lip philtrum length was mainly influenced by the initial overjet before treatment. 4. The decrease of the upper and lower lip vermilion height was mainly influenced by the decrease of upper lip thickness.

• Journal of the Institute of Convergence Signal Processing
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• v.10 no.1
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• pp.7-12
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• 2009

In this paper, we propose a directional feature extraction method for off-line handwritten numerals by using the morphological operations. Direction features are obtained from four directional line images, each of which contains horizontal, vertical, right-diagonal and left-diagonal lines in entire numeral lines. Conventional method for extracting directional features uses Kirsch masks which generate edge-shaped double line images for each direction, whereas our method uses directional erosion operations and generate single line images for each direction. To apply these directional erosion operations to the numeral image, preprocessing steps such as thinning and dilation are required, but resultant directional lines are more similar to numeral lines themselves. Our four [$4{\times}4$] directional features of a numeral are obtained from four directional line images through a zoning method. For obtaining the higher recognition rates of the handwrittern numerals, we use the multiple feature which is comprised of our proposed feature and the conventional features of a kirsch directional feature and a concavity feature. For recognition test with given features, we use a multi-layer perceptron neural network classifier which is trained with the back propagation algorithm. Through the experiments with the CENPARMI numeral database of Concordia University, we have achieved a recognition rate of 98.35%.

• Childhood Kidney Diseases
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• v.23 no.1
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• pp.36-42
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• 2019

Purpose: We investigated whether a renal size discrepancy on a renal sonogram (US) in children with febrile urinary tract infection (UTI) was correlated with the presence of cortical defects on their dimercaptosuccinic acid (DMSA) renal scan. Methods: We examined 911 children who were admitted consecutively to our hospital with their first episode of febrile UTI from March 2001 to September 2014. All enrolled children underwent a US and DMSA scan during admission. According to the US findings, including the renal size discrepancy, data were compared between children with positive and negative DMSA scan results. A positive DMSA scan result was defined as reduced or absent tracer localization and indistinct margins that did not deform the renal contour. Results: Mean renal lengths of the right and left kidneys were larger in children with positive DMSA scan results than in children with negative DMSA scan results ($63.2{\pm}11.3mm$ vs. $58.4{\pm}7.8mm$, P<0.001; $64.9{\pm}11.2mm$ vs. $59.9{\pm}7.9mm$, P<0.001; respectively). A significant difference was observed in both renal lengths between children with positive and negative DMSA scan results ($4.6{\pm}3.8mm$ vs. $3.3{\pm}2.6mm$, P<0.001). A multiple logistic regression analysis, revealed that a small kidney, cortical thinning, and a renal length discrepancy on US findings were significant factors for predicting the presence of cortical defects on an acute DMSA scan [P=0.028, 95% confidence interval (CI) 1.054-2.547; P= 0.004, 95% CI 1.354- 4.810; P<0.001, 95% CI 1.077-1.190, respectively]. Conclusion: In conclusion, a renal size discrepancy on US findings in children with their first episode of febrile UTI was a helpful tool for predicting the presence of cortical defects on an acute DMSA scan.