• Journal of the Korean School Mathematics Society
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• v.21 no.4
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• pp.343-376
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• 2018

The purpose of this study is to compare and analyze the perceptions of TPACK for mathematics teachers who practice the technology-using lessons. In addition, by looking at the part where the perception is expressed in the actual class and the part where the difference of recognition can be revealed, it is possible to provide the direction to teachers who want to practice the technology-using lessons in the future. To do this, two mathematics teachers were selected using purposeful sampling. And we conducted research study and interview in order to analyze the characteristics of the teacher's general background and TPACK recognition, and we analyzed the video, the class materials, and the interview contents for teaching practices from the perspective of TPACK. As a result, the two mathematics teachers practicing the technology-using lessons were connected with the actual class situation focusing on the sub-knowledges of TPACK recognizes as having a lot of them. In addition, technology-based lessons were able to confirm that the functional capabilities of technology alone were not sufficient conditions to lead effective instruction. Finally, teaching method using technology has been confirmed that experience-based field practice can be more important than simply knowing mathematics content, technology, teaching method. Based on the results of this study, it is possible not only to provide methodological guidance to teachers who practice the technology-based instruction, but also to suggest the direction of TPACK research or the development of teacher training program in the future.

• Journal of Broadcast Engineering
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• v.25 no.6
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• pp.973-979
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• 2020

This study aims to objectively and quantitatively determine the social emotion of empathy by collecting pupillary response. 52 subjects (26 men and 26 women) voluntarily participated in the experiment. After the measurement of the reference of 30 seconds, the experiment was divided into the task of imitation and spontaneously self-expression. The two subjects were interacted through facial expressions, and the pupil images were recorded. The pupil data was processed through binarization and circular edge detection algorithm, and outlier detection and removal technique was used to reject eye-blinking. The pupil size according to the empathy was confirmed for statistical significance with test of normality and independent sample t-test. Statistical analysis results, the pupil size was significantly different between empathy (M ± SD = 0.050 ± 1.817)) and non-empathy (M ± SD = 1.659 ± 1.514) condition (t(92) = -4.629, p = 0.000). The rule of empathy according to the pupil size was defined through discriminant analysis, and the rule was verified (Estimation accuracy: 75%) new 12 subjects (6 men and 6 women, mean age ± SD = 22.84 ± 1.57 years). The method proposed in this study is non-contact camera technology and is expected to be utilized in various virtual reality with smart glasses.

• Science of Emotion and Sensibility
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• v.24 no.4
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• pp.107-116
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• 2021

This study aims to investigate the effect of multisensory stimulation on relieving the stress experienced by drivers. The photoplethysmograms (PPGs) of 30 healthy subjects were measured, and their subjective response to stressful situations and normal driving were evaluated. The subjects underwent nonstimulation and multisensory stimulation in stressful driving situations. Heart rate estimation from the PPG was collected via an ear-type sensor to reduce movement noise. The signals acquired were sampled at 200 Hz using BIOPAC PPG100C. Heart rate variability (HRV) was analyzed to compare the effect of multisensory stimulation on stress situations. In the multisensory stimulation, blue, green, and yellow were used for the visual sensory system; white, pink, and brown noises were used for the auditory sensory system; and lavender, lemon, and rosemary were used for the olfactory sensory system. No difference was observed in the subjective evaluation; however, the HRV results showed an increased HF (%) and decreased LF (%) and LF/HF (%) in the multisensory stimulation (e.g., green, pink noise, and rosemary) when compared to the nonstimulation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.21 no.1
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• pp.43-51
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• 1976

Marine deposite soil was studied to evaluate morohological changes of paddy rice under subdrainage control. The content of organic and inorganic mate rial were low at high temperature in the mid-summer. This soil lacked air and accumulated more H$_2$ S. Thus rice root was rotted with high infection of virus and insect and yield was relatively low.

• Journal of the Korean Vacuum Society
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• v.15 no.1
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• pp.97-102
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• 2006

Anodic alumina with self-organized and ordered nano hole arrays can be a good candidate of an irradiation mask to modify the properties of nano-scale region. In order to try using porous anodic alumina as a mask for ion-beam patterning, ion beam transmittance of anodic alumina was tested. 4 Um thick self-standing AAO templates anodized from Al bulk foil with two different aspect ratio, 200:1 and 100:1, were aligned about incident ion beam with finely controllable goniometer. At the best alignment, the transmittance of the AAO with aspect ratio of 200:1 and 100:1 were $10^{-8}\;and\;10^{-4}$, respectively. However transmittance of the thin film AAO with low aspect ratio, 5:1, were remarkably improved to 0.67. The ion beam transmittance of self-standing porous alumina with a thickness larger than $4{\mu}m$ is extremely low owing to high aspect ratio of nano hole and charging effect, even at a precise beam alignment to the direction of nano hole. $SiO_2$ nano dot array was formed by ion irradiation into thin film AAO on $SiO_2$ film. This was confirmed by scanning electron microscopy that the $SiO_2$ nano dot array is similar to AAO hole array.

• Pediatric Infection and Vaccine
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• v.6 no.2
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• pp.239-244
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• 1999

Purpose : In 1998, there was an outbreak of mumps in Taejon, Korea. We analyzed the monthly incidence, clinical manifestations, and complications during the outbreak and the annual incidence of the recent ten years. Methods : We reviewed the clinical records of 35 mumps patients who had been admitted to Taejon St. Mary's Hospital from January to December, 1998. Results : Mumps was prevalent in summer(from June to August) with 20 cases(57%). Thirthy-three patients(94.3%) received MMR at 15 months of age and no patients received a booster mumps vaccine. The mean age of the mumps patients was 10.5 years-old and the majority of mumps(71%) occurred between 5 and 12 year of age. The male female ratio was 2.2 : 1. The clinical manifestations were swelling of parotid gland(100%), fever (91%), vomiting(77%), abdominal pain(74%) and headache(66%) in order of frequency. Meningitis occurred in 20 cases(57%) and the mean WBC count of CSF was $464{\pm}263/mm^3$. In serology, the mean serum amylase level was $483{\pm}294IU/dL$ and anti-mumps IgM and IgG were positive in 11 and 15 out of 18 cases, respectively. From 1989 to 1997, the mean number of inpatients with mumps was 3.4 per year. Conclusion : We experienced an outbreak of mumps in 1998. It is suggested that there was a primary mumps vaccine failure in Korea and that further studies for vaccine faiure and method of booster mumps vaccine are necessary.

• Childhood Kidney Diseases
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• v.3 no.2
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• pp.145-152
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• 1999

Purpose: The prevalence of childhood renal diseases including the nephrotic syndrome in Korea has not been well established. In priority to this point, we analyzed ninety-six nephrotic children of the annual incidence, the ratio of them to all inpatients and estimated incidence of childhood nephrotic syndrome under 15 years of age in Taejon, Korea. Also we classified them by clinical and histopathological findings. Methods: we analyzed the admission and outpatient records retrospectively between June 1986 and December 1998. For the estimation of incidence, we were assisted with three other general hospitals in Taejon Results: The mean annual number and the ratio to inpatients were $7.4{\pm}2.1,\;0.3{\pm}0.11%$ respectively. The latter showed a tendency to decrease during the recent three years. The estimated annual incidences of childhood nephrotic syndrome in Taejon were 5.6 in 1988, 5.5 in 1993 and 4.8 in 1998 per 100,000 for children aged up to 15 years. The mean age of our patients was $6.8{\pm}3.5$ tears, 1-7 years of age was 55 cases(57.3%), and male to female ratio was 3.6:1. By the clinicopathologic classification, 89 cases(92.7%) were classified as primary nephrotic syndrome, and 7 cases(7.3%) as secondary nephrotic syndrome. Among the primary nephrotic syndrome, there was 79.8% of minimal change nephrotic syndrome, focal segmental glomerulosclerosis 11.2%, mesangial proliferation 4.5%, membranoproliferative glomerulonephritis 3.4%, and membranous nephropathy 1.1%. $Henoch-Sch\"{o}nlein$ nephritis was the most frequent of 3 cases in the secondary nephrotic syndrome. Respones to steroid therapy of 71 cases minimal change were classified as non-relapse 22.5%, non-frequent relapse 49.3%, frequent relapse 18.3% and steroid-dependence 9.9%. Conclusion: The estimated incidence of childhood nephrotic syndrome was about 5 per 100,000 for children aged up to 15 years and it showed little changes during 10 years in Taejon, Korea. Our results of clinicopathologic study was little difference from the results reported in other literatures.

• The Korean Journal of Pesticide Science
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• v.14 no.4
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• pp.319-325
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• 2010

To understand the influences of the substituents ($R_1{\sim}R_4$) on insecticidal activity of N'-phenyl-N-methylformamidine analogues (1~22) against two spotted spider mite (Tetranychus urticae), comparative molecular field analysis (CoMFA) model and comparative molecular similarity indices analysis (CoMSIA) model as three dimensional quantitative structure-activity relationships (3D-QSARs) model were derived and discussed quantitatively. From the results, the correlativity and predictability ($r^2{_{cv.}}=0.575$ and $r^2{_{ncv.}}=0.945$) of the CoMFA 1 model were higher than those of the rest models. The the CoMFA 1 and CoMSIA 1 model with the sensitivity of the perturbation and the prediction produced ($d_q{^{2'}}/dr^2{_{yy}}=1.071{\sim}1.146$ & $q^2=0.545{\sim}0.626$) by a progressive scrambling analysis were not dependent on chance correlation. The insecticidal activities from the optimized CoMFA 1 model were depend upon the steric field (62.5%), electrostatic field (28.9%), and hydrophobic field (8.6%) of N'-phenyl-N-methylformamidine analogues. Therefore, the inhibitory activities with optimized CoMFA 1 model were dependent upon steric factor. From the contour maps of the optimized models, it is predicted that the structural distinctions that contribute to the insecticidal activity will be able to applied new potent insecticides design.

• Journal of Chest Surgery
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• v.38 no.3 s.248
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• pp.221-228
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• 2005

Reduction aortoplasty has been advocated for dilatation of the ascending aorta associated with aortic valve disease in older, high-risk patients. We report our results with modification of reduction aortoplasty and aortic valve replacement. Material and Method: Between July 2001 and December 2002, 14 consecutive patients who underwent modification of reduction aortoplasty, suture plication technique without excision of the dilated aortic wall, were reviewed. The mean age was 63.7$\pm$6.7 (50 to 75) years. Ten patients had congenital bicuspid aortic valve, Twelve patients had severe aortic valve stenosis and 6 had regurgitation of grade III$\~$IV. The diameter of the ascending aorta was measured before and immediately after surgery and 6 and 12 months postoperatively using echocardiography or computed tomography. Follow-up was complete in an average of 14.7$\~$5.4 (7 to 24) months. Result: There were no early postoperative deaths and no bleeding complications. Reduction aortoplasty with suture plication technique decreased the diameter of ascending aorta from 49.4$\pm$3.5 mm preoperatively to 33.2$\pm$3.4 mm postoperatively (p <0.001). During follow-up, there were no late deaths and no aneurysm recurrence on the ascending aorta. Conclusion: Suture plication technique of reduction aortoplasty without excision of the dilated aortic wall offers good early and short-term results in older, high-risk patients with dilatation of the ascending aorta associated with aortic valve disease. Surgical long-term results of our technique should be evaluated in further studies.

• Clinical and Experimental Pediatrics
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• v.46 no.5
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• pp.480-483
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• 2003

Purpose : We evaluated clinical manifestations and laboratory findings in patients with measles according to C-reactive protein(CRP) concentration. Methods : A retrospective analysis was performed using the medical records of patients with measles at The Catholic University of Korea, Daejeon St. Mary's Hospital from October 1999 to May 2000. We divided the patients with measles into four groups according to CRP level, i.e., those with below 5 mg/L(134 patients, negative group), those with 6-19 mg/L(85 patients), those with 20-49 mg/L(27 patients), and those over 50 mg/L(7 patients). We compared clinical and laboratory characteristics among these four groups. Results : The mean CRP level of all patients was $11.1{\pm}7.5mg/L$. No statistical differences were present between the negative group and the 6-19 mg/L group or the 20-49 mg/L group in the duration of fever, hospitalization days, complications determined with longer hospitalization for more than eight days, white blood cell count, and incidence of hepatitis. Compared with the negative group, the over 50 mg/L group showed a longer duration of fever($4.7{\pm}1.7$ vs $7.2{\pm}3.9days$), duration of hospitalization($5.4{\pm}1.4$ vs $9.4{\pm}4.7days$), incidence of complications(5.2% vs 42.9%) and a higher mean level of WBC count($5,900{\pm}2,700/mm^3$ vs $12,700{\pm}6,700/mm^3$). With an increasing CRP level, there was a tendency for the duration of fever, complications and WBC count to increase. However the levels of liver enzymes(AST/ALT) were not associated with CRP level. Conclusion : A CRP level of over 50 mg/L in measles is associated with severity and complications.