• Journal of the Korean Association of Geographic Information Studies
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• v.13 no.4
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• pp.111-124
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• 2010

To monitor the environment of land surface change is considered as an important research field since those parameters are related with land use, climate change, meteorological study, agriculture modulation, surface energy balance, and surface environment system. For the change detection, many different methods have been presented for distributing more detailed information with various tools from ground based measurement to satellite multi-spectral sensor. Recently, using high resolution satellite data is considered the most efficient way to monitor extensive land environmental system especially for higher spatial and temporal resolution. In this study, we use two different spatial resolution satellites; the one is SPOT/VEGETATION with 1 km spatial resolution to detect coarse resolution of the area change and determine objective threshold. The other is Landsat satellite having high resolution to figure out detailed land environmental change. According to their spatial resolution, they show different observation characteristics such as repeat cycle, and the global coverage. By correlating two kinds of satellites, we can detect land surface change from mid resolution to high resolution. The K-mean clustering algorithm is applied to detect changed area with two different temporal images. When using solar spectral band, there are complicate surface reflectance scattering characteristics which make surface change detection difficult. That effect would be leading serious problems when interpreting surface characteristics. For example, in spite of constant their own surface reflectance value, it could be changed according to solar, and sensor relative observation location. To reduce those affects, in this study, long-term Normalized Difference Vegetation Index (NDVI) with solar spectral channels performed for atmospheric and bi-directional correction from SPOT/VEGETATION data are utilized to offer objective threshold value for detecting land surface change, since that NDVI has less sensitivity for solar geometry than solar channel. The surface change detection based on long-term NDVI shows improved results than when only using Landsat.

• The Korean Journal of Nuclear Medicine
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• v.34 no.1
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• pp.55-61
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• 2000

Purpose: We performed this study to evaluate the changes of gallbladder ejection fraction (GBEF) in diabetic patients with or without autonomic neuropathy. Materials and Methods: This study included 37 diabetic patients (25 women, 12 men, mean age 51 years) and 24 normal controls (10 women, 14 men, mean age 38 years). After intravenous injection of 185 MBq of $^{99m}Tc$-DISIDA, serial anterior abdominal images were acquired before and after fatty meal. Regions of interest were applied on gallbladder and right hepatic lobe on 60 and 90 minute images to calculate GBEF. Results: GBEF was significantly reduced in diabetes with autonomic neuropathy ($43{\pm}12.3%$) and without autonomic neuropathy ($57.5{\pm}13.2%$) compared with normal controls ($68{\pm}11.6%$, p<0.05). And also, GBEF was significantly reduced in diabetes with autonomic neuropathy compared with diabetes without autonomic neuropathy (p<0.05). Fasting blood glucose level, age, sex, hemoglobin Alc, body mass index, serum lipid level were not different in these two diabetic patient groups (p>0.05). When 50.2% of GBEF was used as the criteria for diabetic autonomic neuropathy, the sensitivity and specificity were 80%, 76.5%, respectively. The area under receiver operating characteristic curve was 0.846. Conclusion: GBEF of diabetic patients with autonomic neuropathy was significantly reduced than that of diabetic patients without autonomic neuropathy.

• Tuberculosis and Respiratory Diseases
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• v.39 no.5
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• pp.400-406
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• 1992

Background: It has been known that see antigen was used in diagnosis of uterine cervical cancer and also known to be higher in squamous cell lung cancer. There has been no report about see antigen in squamous cell lung cancer in Korea. This study was designed to evaluate the usefulness of see antigen as a diagnostic tool and index for follow up after treatment. Method: The serum level of see antigen was measured in 12 cases with squamous cell lung carcinoma, 9 patients with other types of lung cancer, 7 patients with benign lung disease and 7 normal subjects by radioimmunoassay with Abott see Riabeap radioimmunoassay kit. We also measured see antigen after treatment in 6 patients who had received chemotherapy or sugery. Result: 1) The level of see antigen ($mean{\pm}1$ SD) was $2.27{\pm}1.53$, $0.67{\pm}0.38$, $0.62{\pm}0.53$, $0.53{\pm}0.36\;ng/ml$ respectively. 2) The see antigen activity in squamous cell lung carcinoma according to stage were as gollows. I; $2.07{\pm}1.56$, $III_a$; $5.04{\pm}0.53$ $III_b$; $1.94{\pm}0.7$ IV; $1.07{\pm}0.64$ (ng/ml). 3) In squamous cell lung cancer, 5 of 12 (42%) cases was shown more than 2.0 ng/ml see antigen. (sensitivity; 42%), but there was no case in any other type of lung cancer, benign lung disease, and in control groups (specificity; 100%). 4) The serum sec antigen level after treatment was significantly decreased in patients with partial or complete remission (p<0.01). Conclusion; It was suggested that see antigen might be used as a useful tumor marker for the response of treatment and assessment of prognosis in squamous cell lung cancer, but further study should be performed for the clinical use of see antigen.

• Clinical and Experimental Pediatrics
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• v.48 no.5
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• pp.481-487
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• 2005

Purpose : Adiponectin, adipose tissue-specific protein, has anti-inflammatory and anti-atherogenic properties. It has been found to have a negative correlation with obesity and to play a role in modulating glucose tolerance and insulin sensitivity. Serum adiponectin concentrations are decreased in adults with obesity and type 2 diabetes. We investigated the difference in adiponectin levels between obese and non-obese children, and evaluated the relationship of serum adiponectin with body mass index(BMI), serum fasting insulin, lipid profiles and homeostasis model assessment(HOMA) in children. Methods : We measured serum adiponectin levels by radioimmunoassay in 113 children(82 obese children and 31 non-obese controls) from 8 to 15 years of age, and also checked BMI, fasting serum glucose, insulin and lipid profiles. Fasting and postprandial serum adiponectin concentrations were compared by oral glucose tolerance tests in 27 obese children. The correlations of adiponectin with BMI, insulin, low density lipoprotein(LDL)-cholesterol and HOMA were analyzed by Pearson's correlation. Results : The serum adiponectin levels were significantly lower in the obese group(19.7 mg/mL) than in the non-obese group(27.5 mg/mL)(P<0.01). Serum adiponectin concentrations were negatively correlated with BMI(r=-0.39, P<0.01), serum insulin(r=-0.28, P<0.01), LDL-C(r=-0.20, P<0.01) and HOMA(r=-0.22, P<0.01). At oral glucose tolerance tests in obese children, postprandial 2 hours adiponectin level(19.8 mg/mL) was decreased compared to fasting level(25.8 mg/mL)(P<0.01). Conclusion : Serum adiponectin concentrations were inversely related to adiposity and insulin resistance in children. We suggest the serum adiponectin level could be used as an early marker of insulin resistance in obese children.

• Journal of Nutrition and Health
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• v.41 no.5
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• pp.414-427
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• 2008

The purpose of the study was to develop an eating habit checklist for screening elementary school children at high risk of energy overintake. Dietary habits, food intake, anthropometric data were collected from 142 children (80 boys and 62 girls) in the 4th to 6th grades of elementary schools. Energy intake, fat intake, and percentage of Estimated Energy Requirement (%EER) were used as indices to detect the risk of energy overintake of the children. Pearson correlation coefficients were calculated between dietary habit scores and energy overintake indices in order to select questions included in the checklist. TV watching during the meal, meal speed, meal amount, overintake frequency, eatingout frequency, snack frequency, frequency of eating Ramyun or fast foods showed significant correlations with energy overintake indices. Stepwise regression analysis was performed to give each item a different weight by prediction strength. To determine the cut-off point of the test score, sensitivity, specificity, and positive predictive values were calculated. The 7-item checklist with test results from 0 to 13 points was developed, and those with equal or higher than 5 points were diagnosed as a risk group of energy overintake. Among our subjects 13.4% was diagnosed as the risk group. Mean energy intake of the subjects in the risk group and the normal group were 2,650 kcal and 1,640 kcal, respectively. However, there were no significant differences of Index of Nutritional Quality (INQ) of the other nutrients except eating fiber between the risk group and the normal group. This checklist will provide a useful screening tool to identify children at high risk of energy overintake.

• Korean Journal of Psychosomatic Medicine
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• v.20 no.2
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• pp.98-104
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• 2012

Objectives : This study aimed to investigate the correlations between neurological and psychiatric symptoms at two weeks after stroke. Methods : For 412 stroke patients, stroke severity was evaluated by the National Institutes of Health Stroke Scale(NIHSS), disability by the Barthel Index(BI) and modified Rankin Scale(mRS), cognitive function by the Korean Mini-Mental State Examination(K-MMSE), and muscle power by grip strength. Psychiatric symptoms were assessed by Symptom check list-90-Revision(SCL-90-R), consisted of nine symptom domains : Somatization, Obsessive-compulsive, Interpersonal sensitivity, Depression, Anxiety, Hostility, Phobic anxiety, Paranoid ideation, Psychoticism, and Additional items. The correlations between the neurological and psychiatric symptoms were investigated at the time of admission and before discharge(i.e. before and after treatment). Results : At the time of admission, NIHSS score was associated with scores on Phobic anxiety and Additional items ; and scores on BI and mRS were associated with Depression, Phobic anxiety and Additional items. At the time of discharge, NIHSS score was associated with scores on Somatization, Depression, Phobic anxiety, and Additional items ; scores on BI and mRS were associated with scores on Depression, Phobic anxiety and Additional items ; MMSE score was associated with Obsessive-compulsive, Depression, Phobic anxiety, and Additional items ; and grip strength was associated with Somatization, Depression, Anxiety and Additional items. Conclusions : More severe neurological symptoms were associated with higher psychiatric morbidity particularly in depression, phobic anxiety, sleep and appetite disturbance at acute stage of stroke. More intensive psychiatric care and intervention are needed for the high risk group.

• Clinical and Experimental Pediatrics
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• v.48 no.10
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• pp.1126-1131
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• 2005

Purpose : Bronchial hyperresponsiveness(BHR) is considered a hallmark of asthma. Increased levels of eosinophil cationic protein(ECP) have been identified in serum of asthma patients. Several studies have examined the relationship between serum ECP and bronchial responsiveness, expressed as methacholine $PC_{20}$ in asthmatic patients, with conflicting results. The aims of this study were to examine the relationship between serum ECP and ${\Delta}FVC$, another index of bronchial responsiveness, which reflects increased maximal airway response. Methods : Six to 8-year-old children with asthma(n=109) underwent methacholine bronchoprovocation testing. The $PC_{20}$ dose of methacholine and ${\Delta}FVC$ were calculated for each individual from the methacholine dose response curves. Serum ECP levels and blood total eosinophil counts were also measured. Results : Serum ECP correlated with ${\Delta}FVC$(r=0.217, P=0.023), as well as $PC_{20}$(r=-0.208, P=0.030). However, blood eosinophil counts failed to show any correlations with ${\Delta}FVC$(r=0.085, P=0.378) or $PC_{20}$(r=-0.148, P=0.125). ${\Delta}FVC$ did not correlate with $PC_{20}$(r=-0.079, P=0.417). Conclusion : Blood eosinophil activation is associated with both components of BHR including increased sensitivity and increased maximal response in 6-8 year old children with asthma.

• Journal of Astronomy and Space Sciences
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• v.20 no.4
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• pp.283-298
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• 2003

The 2001 Leonid meteor storm has been observed all over the world, and its most intense flux since the last few decades has caused great interest among both laymen and experts. Especially, its maximum hours occurred at dawn hours of Nov. 19 in the east Asia, during which moonless clear night at the Mt. Bohyun allowed us near perfect condition of observation. Observation was carried out in the period of 01:00∼05:40(KST), which include the predicted maximum hours, with all-sky camera installed for upper atmospheric airglow research. Tn this paper we analyze 68 all-sky images obtained in this period, which contain records of 172 meteors. Utilizing the zenith hourly rate(ZHR) of 3000 and magnitude distribution index of 2, which were reported to International Meteor Organization by visible observers in the east Asia, we estimate the limiting magnitude of about 3 for meteors detected in our all-sky images. We then derive magnitudes of 83 meteors with clear pixel brightness outlines among the initially detected 172 meteors by comparing with neighbor standard stars. Angular velocities of meteors needed for computing their passing times over an all-sky image are expressed with a simple formula of an angle between a meteor head and the Leonid radiant point. The derived magnitudes of 83 meteors are in the range of -6∼-1 magnitude, and its distribution shows a maximum new -3mag. The derived magnitudes are much smaller than the limiting magnitude inferred from the comparison with the result of naked-eye observations. The difference may be due to the characteristic difference between nearly instantaneuous naked-eye observations and CCD observations with a long exposure. We redetermine magnitudes of the meteors by adjusting a meteor lasting time to be consistent with the naked-eye observations. The relative distribution of the redetermined magnitudes, which has a maximum at 0 mag., resembles that of the magnitudes determined with the in-principle method. The relative distribution is quite different from ones that decrease monotonically with decreasing magnitudes for meteors(1∼6) sensitive to naked-eye observations. We conclude from the magnitude distribution of our all-sky observation that meteors brighter than about 0 mag., appeared more frequently during the 2001 Leonid maximum hours. The frequent appearance of bright meteors has significantly important implication for meteor research. We noted, however, considerably large uncertainties in magnitudes determined only by comparing standard stars due to the unknown lasting time of meteors and the non-linear sensitivity of all-sky camera.

• Management & Information Systems Review
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• v.36 no.4
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• pp.21-32
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• 2017

Motivated by the recent cases of negligent social responsibility as manifested by foreign luxury fashion brands in Korea, this study investigates whether agency costs depend on the sustainability of different types of corporate governance. Agency costs refer either to vertical costs arising from the relationship between stockholders and managers, or to horizontal costs associated with the potential conflicts between majority and minority stockholders. The firms with luxury fashion brand could spend large sums of money on maintenance of magnificent brand image, thereby increasing the agency cost. On the contrary, the firms may hold down wasteful spending to report a gaudily financial achievement. This results in mitigation of the agency cost. Agency costs are measured by the value of the principal component. First, three ratios are constructed: asset turnover, operating expense to sales, and earnings before interest, tax, and depreciation. Then, the scores of each of these ratios for individual firms in the sample are differenced from the ratios for the benchmark firm of S-OIL. S-OIL was designated as the best superior governance model firm for 2013 by CGS. We perform regression analysis of each agency cost index, luxury fashion brand dummy and a set of control variables. The regression results indicate that the agency costs of the firms with luxury fashion brand exceed those of control group in the fashion industry in the part of operating expenses, but the agency cost falls short of those of control group in the part of EBITD, thus the aggregate agency costs are not differential of those of the control group. In sensitivity test, the results are same that the agency cost of the firms are higher than those of the matching control group with PSM(propensity matching method). These results are corroborated by an additional analysis comparing the group of the companies with the best brands with the control group. The results raise doubts about the effectiveness of management of the firms with luxury fashion brand. This study has a limitation that the research has performed only for 2013 and this paper suggests that there is room for improvement in the current research methodology.

• Sleep Medicine and Psychophysiology
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• v.7 no.1
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• pp.27-33
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• 2000

Objectives: The sensitivity and accuracy of thermistor airflow signal has been debated. The purposes of this study were to compare apnea-hypopnea index(AHI) detected from a conventional thermistor signal and a nasal pressure transducer of airflow(NPT), to evaluate the value of NPT for the diagnosis of upper airway resistance syndrome(UARS), and to measure airway pressure fluctuations which produced respiratory arousals in UARS by naso-oro-esophageal manometer catheter. The subjects were 30 patients with obstructive sleep apnea syndrome [mild(540), 10), and 6 UARS patients. Airway resistance arousal in this study was defined as arousals which were not associated with apnea or hypopnea of thermistor signal, but showed significant decrease of nasal airflow pressure just before arousal and a prompt recovery of nasal airflow pressure after arousal. The airway pressure fluctuations were measured during 260 airway resistance arousals observed in 10 patients with OSAS, 2 with UARS. Results: Mean AHIs of patients with OSAS were 33.4 by thermistor and 48.4 by NPT. The AHIs of mild, moderate and severe OSAS groups were 10.2, 32.1, 65.4 respectively by thermistor and 23.1, 45.9, 76.4 by NPT. The mean AHI of patients with UARS was 3.2 by thermistor and 10.8 by NPT. The mean AHI of patients with nonspecific arousals was 2.7 by thermistor and 4.4 by NPT. The mean airway pressure changes during respiratory arousals of different groups were $8.7\;cmH_2O$ in mild OSAS, $11.4\;cmH_2O$ in moderate OSAS, $24.7\;cmH_2O$ in severe OSAS and $6.6\;cmH_2O$ in UARS. Conclusion: The nasal pressure transducer of airflow was more sensitive and accurate for assessing respiratory disturbances of patients with OSAS and was extremely helpful for the diagnosis of UARS without esophageal pressure monitoring. From the results, we would like to propose carefully the NPT diagnostic criteria for sleep disordered breathing as follows: NPT-AHI 5-15 $\rightarrow$ UARS, 15-35 $\rightarrow$ mild OSAS, 35-55 $\rightarrow$ moderate OSAS and >55 $\rightarrow$ severe OSAS.