• Journal of Astronomy and Space Sciences
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• v.26 no.1
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• pp.25-30
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• 2009

We report the relation between the solar activity and terrestrial climate change with the solar north-south asymmetry. For this purpose, we calculate sliding correlation coefficients between sunspot numbers and earth's mean annual temperature anomalies. Then, we compare the epoch that the sign of correlation changes with the epoch that the sign of the solar north-south asymmetry changes. We obtain that corresponding times are 1907 and 1985, respectively. Further more, these two epoches are well consistent with those of signs of the solar north-south asymmetry changes. We also obtain that the plot between sunspot numbers and temperature anomalies could be classified by 1907 and 1985. We conclude that temperature anomalies are shown to be negatively correlated with sunspot numbers when the southern solar hemisphere is more active: and vice versa.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.5 no.4
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• pp.47-63
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• 1994

An important parameter in characterizing mobile communication channel is delay spread. This paper presents the results of measured delay profiles and calculated distribution funcations of delay spread for typical cellular service environments at Taejon and vicinities. The measurement system uses 1023 chip length, 5 Mbps PN code and sliding correlation method. It has been evaluated by using commercial hardware channel simulator for reliability of out data. As results the value of mean delay spread is 2.08 $\mu\textrm{s}$for suburban area. 2.12 $\mu\textrm{s}$ for urban area and 1.3 $\mu\textrm{s}$ for national/local road. Delay spread is less then 3.4$\mu\textrm{s}$, 2.8$\mu\textrm{s}$ and 1.5 $\mu\textrm{s}$ for probability of 50% and 4.5$\mu\textrm{s}$, 4.2$\mu\textrm{s}$ and 2.9$\mu\textrm{s}$ for probability of 90% at each tested site. The difference of delay spread is within 7% between going and returning status along same street. In this experiment, we found delay spread for suburban area is larger than reported foreign test results.

• Composites Research
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• v.19 no.2
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• pp.28-34
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• 2006

[ $Cu-TiB_2$ ] metal matrix composites with various weight fractions of $TiB_2$ were fabricated by combination of manufacturing process, SPS (self-propagating high-temperature synthesis) and SPS (spark plasma sintering). The feasibility of $Cu-TiB_2$ composites for welding electrodes and sliding contact material was investigated through experiments on the tensile properties, hardness and wear resistance. To obtain desired properties of composites, composites are designed according to reinforcement's shape, size and volume fraction. Thus proper modeling is essential to predict the effective material properties. The elastic moduli of composites obtained by FEM and tensile test were compared with effective properties from the original Eshelby model, Eshelby model with Mori-Tanaka theory and rule-of-mixture. FEM result showed almost the same value as the experimental modulus and it was found that Eshelby model with Mori-Tanaka theory predicted effective modulus the best among the models.

• Journal of Oral Medicine and Pain
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• v.31 no.3
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• pp.245-254
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• 2006

While orofacial pain or various dental factors are generally considered as the primary cause of unilateral chewing tendency, there exist several studies indicating that dental factors did not affect the preferred chewing side. The aim of this study was to examine difference of occlusal scheme between the subjects with and without chewing side preference. The difference between the chewing and non-chewing sides in the unilateral chewing group was investigated as well. Computerized, T-Scan II system was used for occlusal analysis. 20 subjects for the unilateral chewing group (mean age of $25.25{\pm}2.84$ years) and 20 subjects for the bilateral chewing group (mean age of $27.00{\pm}5.07$ years) were selected by a questionnaire on presence or absence of chewing side preference and those with occlusal problem or pain and/or dysfunction of jaw were excluded. T-Scan recordings were obtained during maximum intercuspation and excursion movement. The number of contact points, relative occlusal force ratio between right and left sides, tooth sliding area and elapsed time throughout the maximum intercuspation were calculated. Elapsed time for excursion was also investigated. The results of this study shows that the unilateral chewing group had the smaller average tooth contact areas compared with those of the bilateral group (p<0.005). In the unilateral chewing group, the contact areas of non-chewing side are smaller than those of chewing side (p<0.005). The contact areas on their preferred sides were not significantly different with those of right or left side of the subjects without chewing side preference. There was no significant difference in the elapsed time during maximum intercuspation and lateral excursion, the sliding areas and relative of right-to-left occlusal force ratio between the two groups. From the results of this study, it is likely that individuals prefer chewing on the side with more contact areas for efficient chewing.

• The Journal of Korean Society for Radiation Therapy
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• v.26 no.2
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• pp.239-245
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• 2014

Purpose : The purpose of this study is to verify the accuracy of dose delivery according to the pitch and roll rotational setup error with 6D robotic couch in Intensity Modulated Radiation Therapy (IMRT) for pelvic region in patients. Materials and Methods : Trilogy(Varian, USA) and 6D robotic couch(ProturaTM 1.4, CIVCO, USA) were used to measure and analyze the rotational setup error of 14 patients (157 setup cases) for pelvic region. The total 157 Images(CBCT 78, Radiography 79) were used to calculate the mean value and the incidence of pitch and roll rotational setup error with Microsoft Office Excel 2007. The measured data (3 mm, 3%) at the reference angle ($0^{\circ}$) without couch rotation of pitch and roll direction was compared to the others at different pitch and roll angles ($1^{\circ}$, $1.5^{\circ}$, $2^{\circ}$, $2.5^{\circ}$) to verify the accuracy of dose delivery by using 2D array ionization chamber (I'mRT Matrixx, IBA Dosimetry, Germany) and MultiCube Phantom(IBA Dosimetry, Germany). Result from the data, gamma index was evaluated. Results : The mean values of pitch and roll rotational setup error were $0.9^{\circ}{\pm}0.7$, $0.5^{\circ}{\pm}0.6$. The maximum values of them were $2.8^{\circ}$, $2.0^{\circ}$. All of the minimum values were zero. The mean values of gamma pass rate at four different pitch angles ($1^{\circ}$, $1.5^{\circ}$, $2^{\circ}$, $2.5^{\circ}$) were 97.75%, 96.65%, 94.38% and 90.91%. The mean values of gamma pass rate at four different roll angles ($1^{\circ}$, $1.5^{\circ}$, $2^{\circ}$, $2.5^{\circ}$) were 93.68%, 93.05%, 87.77% and 84.96%. when the same angles ($1^{\circ}$, $1.5^{\circ}$, $2^{\circ}$) of pitch and roll were applied simultaneously, The mean values of each angle were 94.90%, 92.37% and 87.88%, respectively. Conclusion : As a result of this study, it was able to recognize that the accuracy of dose delivered is lowered gradually as pitch and roll increases. In order to increase the accuracy of delivered dose, therefore, it is recommended to perform IGRT or correct patient's position in the pitch and roll direction, to improve the quality of treatment.

• Journal of Chest Surgery
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• v.39 no.4 s.261
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• pp.275-280
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• 2006

Background: Aortopulmonary window (APW) is a very rare congenital heart anomaly, often associated with other cardiac anomalies. It causes a significant systemic to pulmonary artery shunt, which requires early surgical correction. Accurate diagnosis and surgical correction will bring good outcomes. The purpose of this study was to describe our 20-year experience of aortopulmonary window. Material and Method: Between March 1985 and January 2005, 16 patients with APW underwent surgical repair. Mean age at operation was $157.8{\pm}245.3$ ($15.0{\sim}994.0$) days and mean weight was $4.8{\pm}2.5$ ($1.7{\sim}10.7$) kg. Patent ductus arteriosus (8), atrial septal defect (7), interruptedaortic arch (5), ventricular septal defect (4), patent foramen ovate (3), tricuspid valve regurgitation (3), mitral valve regurgitation (2), aortic valve regurgitation (1), coarctation of aorta (1), left superior vena cavae (1), and dextrocardia (1) were associated. Repair methods included 1) division of the APW with primary closure or patch closure of aorta and pulmonary artery primary closure or patch closure (11) and 2) intra-arterial patch closure (3). 3) Division of the window and descending aorta to APW anastomosis (2) in the patients with interrupted aortic arch or coarctation. Result: There was one death. The patient had 2.5 cm long severe tracheal stenosis from carina with tracheal bronchus supplying right upper lobe. The patient died at 5th post operative day due to massive tracheal bleeding. Patients with complex aortopulmonary window had longer intensive care unit and hospital stay and showed more morbidities and higher reoperation rates. 5 patients had reoperations due to left pulmonary artery stenosis (4), right pulmonary artery stenosis (2), and main pulmonary artery stenosis (1). The mean follow-up period was $6.8{\pm}5.6$ (57.0 days$\sim$16.7 years)years and all patients belonged to NYHA class 1. Conclusion: With early and prompt correction of APW, excellent surgical outcome can be expected. However, optimal surgical method needs to be established to decrease the rate of stenosis of pulmonary arteries.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.11
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• pp.705-710
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• 2017

This paper proposes an estimation method of populations of Grapholita molestas using object segmentation and an SVM classifier in the moth images. Object segmentation and moth classification were performed on images of Grapholita molestas moth acquired on a pheromone trap equipped in an orchard. Object segmentation consisted of pre-processing, thresholding, morphological filtering, and object labeling process. The classification of Grapholita molestas in the moth images consisted of the training and classification of an SVM classifier and estimation of the moth populations. The object segmentation simplifies the moth classification process by segmenting the individual objects before passing an input image to the SVM classifier. The image blocks were extracted around the center point and principle axis of the segmented objects, and fed into the SVM classifier. In the experiments, the proposed method performed an estimation of the moth populations for 10 moth images and achieved an average estimation precision rate of 97%. Therefore, it showed an effective monitoring method of populations of Grapholita molestas in the orchard. In addition, the mean processing time of the proposed method and sliding window technique were 2.4 seconds and 5.7 seconds, respectively. Therefore, the proposed method has a 2.4 times faster processing time than the latter technique.

• Archives of Plastic Surgery
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• v.35 no.1
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• pp.48-55
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• 2008

Purpose: We measured linear distances, angles and inclinations on the cast models of the noses, and compared these indirect measurements with the direct measurements obtained from the nose in order to validate the accuracy of the indirect anthropometry using the cast model. Methods: Subjects were 50 males and 50 females, medical students in twenties(mean 27.1 years). Cast models were made from the alginate impression material and the plaster. In direct anthropometry, 16 linear, 7 angular, and 2 inclination measurements between 11 landmarks on the nose were obtained using sliding caliper, spreading caliper, and fabric tape measure. At the same time, the same measurements were obtained from the cast models of the same people. Total 25 measurements were compared, and tested by the independent t-test of SPSS. Results: The standard values of Korean nose in twenties were obtained. 24 measurements except the columellar labial angle were not statistically different between the indirect anthropometry and the direct anthropometry. Conclusion: Indirect anthropometry on the cast model of the nose revealed no significant difference from the anthropometric measurement statistically, accounting for 24 in 25 measurements(96%). There are two possible reasons that caused the difference of columellar labial angle between direct and indirect anthropometry. First, the columellar labial angle could be decreased by protrusion of the lips which resulted from contracting mouth in which an drinking straw had been applied on the mouth corner for patients' respiration during making cast model. Second, it is generally known that the columellar labial angle could be measured larger when soft tissues were pressed by protractor in direct anthropometry. Using a drinking straw with greater diameter, and scheming respiration through the nostrils that patients don't feel discomfort, the more accurate data would be obtained from the indirect anthropometry using the cast models of the noses.

• Archives of Plastic Surgery
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• v.36 no.2
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• pp.174-182
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• 2009

Purpose: The Mulliken's method is a one of the very excellent technique to correction of the unilateral cleft lip. It could decrease the need of additional operation and second operation by the early simultaneous correction of unilateral cleft lip and nasal deformity, at a time. Numerous procedures were advocated for the correction of nasal deformity, but with general dissatisfaction of the results, it became obvious that no one procedure is the ideal one. The authors have been operating on unilateral cleft lip by Mulliken's method and long term follow - up of postoperative result was evaluated. Methods: The authors have done long term follow - up of result in the 75 cases unilateral cleft lip patient, during 1 ~ 7 years. That was repaired by simultaneous correction of cleft lip and nasal deformity by Mulliken's method at the period from June, 1997 to December, 2007. The patients were unilateral complete cleft lip 39 cases, unilateral incomplete cleft lip 36 cases. In the severe complete cleft lip cases, lip adhesion operation was done before definite operation. The mean age of unilateral cleft lip operation was 3.2 months. Five anthropometric parameters, which were upper lip, cutaneous lip and vermilion mucosa height, nasal tip protrusion, columella length were measured by Sliding Vernier Caliper. The anthropometric analysis was performed preoperative and postoperative at 6 months, 3, 5 and 7 years and the results were com pared with those of age - matched, normal children. T - tests were used to analyze the differences between the measurements. Results: Long - term postoperative results were evaluated by anthropometrically. Most patients showed adequate growth of upper lip height, vermilion mucosa height and columella length. But nasal tip protrusion was relatively short compare with normal value. Incomplete cleft lip group was nearly normal growth results than complete cleft lip group. Conclusion: In conclusion, we could make harmonious Cupid's bow, natural philtrum and lip, appropriate nasal shape by Mulliken's method. But nasal tip protrusion was under the normal values on complete and incomplete group. And incomplete group was more good results than complete group. We have experienced repair of cleft lip by Mulliken's method with 75 cases of unilateral cleft lip patients and conclude that it was very useful and good method.

• Journal of Chest Surgery
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• v.35 no.12
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• pp.882-889
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• 2002

Acute Complications of Remodelling Plasty of Costochondral Rib Cage For Pectus excavatum Recently, Remodelling Plasty of Costochondral Rib Cage has been introduced as an minimally invasive procedure and expanded its application for pectus excavatum. Outcomes and acute complications were reviewed Material and Method: A retrospective survey of 55 patients who underwent Remodelling Plasty of Costochondral Rib Cage from September, 1999 to February, 2002 was conducted to review complications, postoperative treatments, and outcomes. Result: Age ranged from 1 to 27 years(mean 11.4 $\pm$ 7.1). 35(64%) were less than 15-year old and 20(36%) were more than 15-year old. There were 44(80%) Male patients and 11(20%) female patients. Length of hospital stay was 7.8 $\pm$ 2.1 days for less than 15-Y-old group, 10.6 $\pm$ 6.2 days for more than 15-Y-old group(p ＝ 0.042) One substernal bar was inserted in 52 patients and two substernal bars were inserted in 3 patients. As for stabilizer, one lateral side was fastened in 15 patients and both lateral sides were fastened in 6 patients. In the less than 15-Y-old group, 4 patients needed stabilizer, whereas in the more than 15-Y-old group, 18 patients needed stebilizer(s)(p ＝ 0.000). Including all kinds of complications, 28(51 %)patients had postoperative complications. Of them, only 7 patients were treated for complications(C-tube insertion was done in 7 patients and reoperation for bar refixation or removal was done in 3 patients of them). Conclusion: Most complications after Remodelling Plasty of Costochondral Rib Cage For Pectus Excavatum were trivial without treatment although C-tube drainage was needed in some patients. However bar displacement such as rotation and lateral sliding should be corrected as soon as detected in order not to remove the bar(the worst situation).