• Korean Journal of Remote Sensing
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• v.14 no.3
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• pp.213-222
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• 1998

Electro-Optical Camera(EOC) is the main payload of the KOrea Multi-Purpose SATellite(KOMPSAT) with the mission of cartography to build up a digital map of Korean territory including a Digital Terrain Elevation Map(DTEM). This instalment which comprises EOC Sensor Assembly and EOC Electronics Assembly produces the panchromatic images of 6.6 m GSD with a swath wider than 17 km by push-broom scanning and spacecraft body pointing in a visible range of wavelength, 510~730 nm. The high resolution panchromatic image is to be collected for 2 minutes during 98 minutes of orbit cycle covering about 800 km along ground track, over the mission lifetime of 3 years with the functions of programmable gain/offset and on-board image data storage. The image of 8 bit digitization, which is collected by a full reflective type F8.3 triplet without obscuration, is to be transmitted to Ground Station at a rate less than 25 Mbps. EOC was elaborated to have the performance which meets or surpasses its requirements of design phase. The spectral response, the modulation transfer function, and the uniformity of all the 2592 pixel of CCD of EOC are illustrated as they were measured for the convenience of end-user. The spectral response was measured with respect to each gain setup of EOC and this is expected to give the capability of generating more accurate panchromatic image to the users of EOC data. The modulation transfer function of EOC was measured as greater than 16 % at Nyquist frequency over the entire field of view, which exceeds its requirement of larger than 10 %. The uniformity that shows the relative response of each pixel of CCD was measured at every pixel of the Focal Plane Array of EOC and is illustrated for the data processing.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.3
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• pp.459-473
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• 2004

Recently, many children have been treated under sedation in the department of pediatric dentistry of the dental hospital of Kangnung National University, and sedation cases are increasing gradually. So, in this study. the author analyzed and studied about the characteristics of sedated pediatric dental patients and their parents with patient chart and questionnaire at first visit, from 1999 to 2002 for the purpose of making pediatric dental treatment plan more effective and the improvement of behavior management for better pediatric dentistry. The results were follows : 1. The number of total pediatric and sedative patients increased from 1999 to 2002. 2. The sedated pediatric dental patients were younger than total pediatric dental patients(p<0.001). 3. In visit frequency per month, the sedated patients showed higher percentage on March, July, November contrast to non-sedated patients(p<0.001). 4. In parental occupation, there was a significant difference between sedated patients and non-sedated patients(p<0.001). 5. Caries treatment rather than preventive care or orthodontic treatment, was primarily composed of chief complaint of sedated patients(p<0.001). 6. The sedated patients showed worse response to previous treatment than non-sedated patients, and their parents also expected worse response contrast to non-sedated patients (p>0.001). 7. The patients who were introduced, occupied 31.2% of sedated pediatric dental patients and referral by the dentist were composed of the highest percentage(58.3%). 8. In case of uncooperative child at conventional behavior management, the parents of sedated pediatric dental patients prefered to sedation(50.9%). while the parents of non-sedated patients prefered to physical restraint(54.6%) (p<0.001).

• Journal of the Korean Chemical Society
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• v.50 no.6
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• pp.494-505
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• 2006

This study was performed for 7th grade students to analyze by leader style, the verbal interactions between students in a small group in an MBL(Microcomputer-Based Laboratory) experiment class. The study was performed after arranging the students into four kinds of groups, including groups with leaders of inclusive, persuasive, and alienating styles and a group with no clear leader. The analysis of total frequencies of verbal interaction revealed that the group with an inclusive leader showed the highest frequency of verbal interaction, followed by the group with a persuasive leader, an alienating leader and lastly, the group with no clear leader. The group with an inclusive leader showed the highest frequency of interaction from a cognitive aspect related to question(Q), response(R), making suggestion(MS), and receiving opinions(RO), while interactions from an affective aspect related to behavioral participation(BP) and students' attitudes(SA) were observed more often in a group including an alienating leader than in any other group. An analysis of characteristics of verbal interaction according to leader style showed that a group with an inclusive leader had a permissive atmosphere. It also showed that all members of the group actively participated in discussion and they had a sense of belonging and self-pride with their group. In a group with a persuasive leader, the leader took the lead of most experimental and discussion activities and he was rarely challenged by other students in the group. Rather, other group members showed a tendency to depend on their leader. In a group with an alienating leader, the relationship between leader and members of the group was not harmonious and unfiltered expressions of dissatisfaction and ignorance often took place. The leader's lack of concern about members' low achievement became an obstacle in active discussion. In a group with no clear leader, most interactions during discussion were short and simple. Many answers to the question given by their members were not clear and the interactions were sometimes interrupted for a short while.

• Clinical and Experimental Pediatrics
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• v.50 no.7
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• pp.672-677
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• 2007

Purpose : To assess the prevalence and characteristics of headache comorbidity with epilepsy in children and adolescents in a specialty epilepsy clinic. Methods : Two hundred twenty nine consecutive patients attending the Chosun University Hospital Pediatric Epilepsy Clinic (mean age $10.0{\pm}4.1\;years$, range 4-17, M:F ratio 1.1:1.0) were interviewed with a standardized headache questionnaire. Headache was classified according to the International Classification of Headache Disorders, 2nd Edition and epilepsy was classified according to the International League Against Epilepsy. Disability was assessed using pediatric migraine disability assessment (PedMIDAS). Results : Of the 229 epilepsy patients, 86 (37.6%) had co-morbid headache. Of the headache patients, 64 (74.4%) had migraine (65.6%- migraine without aura, 20.3% - migraine with aura, 14.1% - probable migraine). The mean headache frequency was $7.2{\pm}8.4$ per month, mean duration was $2.2{\pm}4.0$ hours, mean severity was $5.2{\pm}2.2$ out of 10, and mean PedMIDAS score was $13.0{\pm}35.4$. The proportion of females was not higher in epilepsy with headache patients (48.8%) compared to epilepsy patients alone (48.0%). In the patients with migraine, 48.4% had complex partial seizures, 17.2% had simple partial seizures, and 34.4% had generalized seizures (P=0.368). A postictal association of migraine was reported in 18.8% with 17.2% reporting a preictal headache, and 7.8% reporting an ictal headache. Conclusion : The prevalence of headache in pediatric epilepsy is higher than that in general pediatric population, suggesting a co-morbidity of headache in epilepsy patients with migraine being the most frequent headache disorder. Altered cerebral excitability resulting in an increased occurrence of spreading depression may explain the headache comorbidity with epilepsy. Further studies are needed to assess the etiology of this co-morbidity as well as assess the frequency, duration, severity and disability response to antiepileptic drugs.

• Journal of Cadastre & Land InformatiX
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• v.50 no.1
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• pp.107-123
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• 2020

With stabilization of the recent multi-GNSS infrastructure, and as multi-GNSS has been proven to be effective in improving the accuracy of the positioning performance in various industrial sectors. In this study, in view that SF(Single frequency) GNSS receivers are widely used due to the low costs, evaluate effectiveness of SF Real Time Point Positioning(SF-RT-PP) based on four multi-GNSS surveying methods with RTCM-SSR correction streams in static and kinematic modes, and also derive response challenges. Results of applying SSR correction streams, CNES presented good results compared to other SSR streams in 2D coordinate. Looking at the results of the SF-RT-PP surveying using SF signals from multi-GNSS, were able to identify the common cause of large deviations in the altitude components, as well as confirm the importance of signal bias correction according to combinations of different types of satellite signals and ionospheric delay compensation algorithm using undifferenced and uncombined observations. In addition, confirmed that the improvement of the infrastructure of Multi-GNSS allows SF-RT-SPP surveying with only one of the four GNSS satellites. In particular, in the case of code-based SF-RT-SPP measurements using SF signals from GPS satellites only, the difference in the application effect between broadcast ephemeris and SSR correction for satellite orbits/clocks was small, but in the case of ionospheric delay compensation, the use of SBAS correction information provided more than twice the accuracy compared to result of the Klobuchar model. With GPS and GLONASS, both the BDS and GALILEO constellations will be fully deployed in the end of 2020, and the greater benefits from the multi-GNSS integration can be expected. Specially, If RT-ionospheric correction services reflecting regional characteristics and SSR correction information reflecting atmospheric characteristics are carried out in real-time, expected that the utilization of SF-RT-PPP survey technology by multi-GNSS and various demands will be created in various industrial sectors.

• Journal of the Korean Ceramic Society
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• v.49 no.5
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• pp.404-411
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• 2012

The reliability of solid oxide fuel cells (SOFCs) particularly depends on the high quality of solid oxide electrolytes. The application of thinner electrolytes and multi electrolyte layers requires a more reliable characterization method. Most of the investigations on thin film solid electrolytes have been made for the parallel transport along the interface, which is not however directly related to the fuel cell performance of those electrolytes. In this work an array of ion-blocking metallic Ti/Au microelectrodes with about a $160{\mu}m$ diameter was applied on top of an ultrathin ($1{\mu}m$) yttria-stabilized-zirconia/gadolinium-doped-ceria (YSZ/GDC) heterolayer solid electrolyte in a micro-SOFC prepared by PLD as well as an 8-${\mu}m$ thick YSZ layer by screen printing, to study the transport characteristics in the perpendicular direction relevant for fuel cell operation. While the capacitance variation in the electrode area supported the working principle of the measurement technique, other local variations could be related to the quality of the electrolyte layers and deposited electrode points. While the small electrode size and low temperature measurements increaseed the electrolyte resistances enough for the reliable estimation, the impedance spectra appeared to consist of only a large electrode polarization. Modulus representation distinguished two high frequency responses with resistance magnitude differing by orders of magnitude, which can be ascribed to the gadolinium-doped ceria buffer electrolyte layer with a 200 nm thickness and yttria-stabilized zirconia layer of about $1{\mu}m$. The major impedance response was attributed to the resistance due to electron hole conduction in GDC due to the ion-blocking top electrodes with activation energy of 0.7 eV. The respective conductivity values were obtained by model analysis using empirical Havriliak-Negami elements and by temperature adjustments with respect to the conductivity of the YSZ layers.

• Journal of the Korean Society for Nondestructive Testing
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• v.34 no.3
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• pp.220-225
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• 2014

Generally, the nonlinearity of ultrasonic waves is measured using a nonlinear parameter ${\beta}$, which is defined as the ratio of the second harmonic's magnitude to the power of the fundamental frequency component after the ultrasonic wave propagates through a material. Nonlinear parameter ${\beta}$ is recognized as an effective parameter for evaluating material degradation. In this paper, we evaluated the nonlinear parameter of Al6061-T6 which had been subjected to an artificial aging heat treatment. The measurement was using the transmitted signal obtained from contact-type transducers. After the ultrasonic test, a micro Vickers hardness test was conducted. From the result of the ultrasonic nonlinear parameter, the microstructural changes resulting from the heat treatment were estimated and the hardness test proved that these estimates were reasonable. Experimental results showed a correlation between the ultrasonic nonlinear parameter and microstructural changes produced by precipitation behavior in the material. These results suggest that the evaluation of mechanical properties using ultrasonic nonlinear parameter ${\beta}$ can be used to monitor variations in the mechanical hardness of aluminum alloys in response to an artificial aging heat-treatment.

• Atmosphere
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• v.18 no.3
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• pp.183-197
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• 2008

The purpose of this study is to summarize tropical cyclone activity in 2007. 24 tropical cyclones of tropical storm (TS) intensity or higher formed in the western North Pacific and the South China Sea in 2007. The total number is less than the thirty-year (1971~2000) average frequency of 26.7. Out of twenty four tropical cyclones, 14 TCs reached typhoon (TY) intensity, while the rest 10 only reached severe tropical storm (STS) and tropical storm (TS) intensity - four STS and six TS storms. The tropical cyclone season in 2007 began in April with the formation of KONG-REY (0701). From April to May, two TCs formed in the western North Pacific in response to enhanced convective activity there. From June to July, convective activity turned inactive over the sea around the Philippines and in the South China Sea, and the subtropical high was weak over the south of Japan. MAN-YI (0704) and USAGI (0705) moved northwestward and hit Japan, bringing serious damage to the country. After August, convective activity became enhanced over the sea east of the Philippines, and the subtropical high turned strong over the sea south of Japan. Many TCs, which formed over the sea east of the Philippines and in the South China Sea, moved westward and hit China and Vietnam. PABUK (0706), WUTIP (0707), SEPAT (0708), WIPHA (0712), LEKIMA (0714) and KROSA (0715) brought serious damage to some countries including China, the Philippines and Vietnam. On the other hand, FITOW (0709) and NARI (0711) moved northward, bringing serious damage to Japan and Korea. After HAIYAN (0716), all four TCs except FAXAI (0720) formed over the sea east of $140^{\circ}E$. Three typhoons among them affected Republic of Korea, MAN-YI (0704), USAGI (0705) and NARI (0711). Particularly, NARI (0711) moved northward and made landfall at Goheng Peninsula ($34.5^{\circ}N$, $127.4^{\circ}E$) in 1815 KST 16 September. Due to $11^{th}$ typhoon NARI, strong wind and record-breaking rainfall amount was observed in Jeju Island. It was reported that the daily precipitation was 420.0 mm at Jeju city, Jeju Island on 16 September the highest daily rainfall since Jeju began keeping records in 1927. This typhoon hit the southern part of the Korean peninsula and Jeju Island. 18 people lost their lives, 14,170 people were evacuated and US$ 1.6 billion property damage was occurred.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.1
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• pp.321-326
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• 2014

Background: Mutations in the tyrosine kinase domain of the epidermal growth factor receptor (EGFR) in non-small cell lung cancer (NSCLC) are predictive of response to EGFR-targeted therapy in advanced stages of disease. This study aimed to determine the frequency of EGFR mutations in NSCLCs and to correlate their presence with clinical characteristics in multiethnic Malaysian patients. Materials and Methods: In this prospective study, EGFR mutations in exons 18, 19, 20 and 21 in formalin-fixed paraffin-embedded biopsy specimens of consecutive NSCLC patients were asessed by real-time polymerase chain reaction. Results: EGFR mutations were detected in NSCLCs from 55 (36.4%) of a total of 151 patients, being significantly more common in females (62.5%) than in males (17.2%) [odds ratio (OR), 8.00; 95% confidence interval (CI), 3.77-16.98; p<0.001] and in never smokers (62.5%) than in ever smokers (12.7%) (OR, 11.50; 95%CI, 5.08-26.03; p<0.001). Mutations were more common in adenocarcinoma (39.4%) compared to non-adenocarcinoma NSCLCs (15.8%) (p=0.072). The mutation rates in patients of different ethnicities were not significantly different (p=0.08). Never smoking status was the only clinical feature that independently predicted the presence of EGFR mutations (adjusted OR, 5.94; 95%CI, 1.94-18.17; p=0.002). Conclusions: In Malaysian patients with NSCLC, the EGFR mutation rate was similar to that in other Asian populations. EGFR mutations were significantly more common in female patients and in never smokers. Never smoking status was the only independent predictor for the presence of EGFR mutations.

• Korean Journal of Health Education and Promotion
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• v.5 no.2
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• pp.110-141
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• 1988

This study was conducted to find out the mental health state of high school students. First-year students and third-year students af liberal high schools is Seoul were subject to this study. Questionnaire of Symptom Checklist-90 and various factors was adopted for the survey. A total of 916 questionnaires was sellected for the analysis, and the results are obtained as follows; 1) The characteristics in responses to mental health scale showed that obsessive-compulsive scale score was the highest, followed by interpersonal-sensitivity, depression, hostility, and anxiety. The subject group of the students showed higher scores in nine symptom dimensions except somatization than other normal group. 2) Girl-students showed higher scores than boy-students in somatization, depression, and anxiety, whereas the opposite was true in hostility. 3) Third-year students got high scores, in somatization, anxiety and Depression. 4) Parental marriage state of the repondents showed significant differences in nine symptom dimensions of mental health. Scores of the students with parents was the lowest, followed by those of students with only mother, only father and the rest(no parents, divorced, sepaerated, step-parent) in increasing order. 5) Smoking students showed high score in obsessive-compulsive, depression, hostility, paranoid ideation, and psychoticism. Especially in hostility, they got much higher score. 6) Students with poor record at school got higher scores in every symptom dimension than those with good record at school, especially in obsessive-compulsive and depression scale. 7) Parents' attitude toward student showed significant effect on every scale. Students under over-expectation or indifference from parents were in bad mental health state. 8) Students who have advisor proved to be in better mental health state than those who never consult their personal problems with others. 9) He who has family history got higher scores in some scales. 10) Respondents who looked upon what they have learned in high school as being rather an obstacle to sound social life got high scores in all the symptom dimensions and next came those of the students who answered that there were a lot of unnecessary things in their learning. 11) Those for whom it would not quite necessary to enter college if there were little formal schooling discrimination in society got high scores in obsessive-compulsive, interpersonal sensitivity, depression, hostility, and in psychoticism, especially higher in obsessive-compulsive scale. 12) Mental health state of the students who are influenced by the social surroundings, mass media, and the home environments showed high score in 8 symptom dimensions. 13) Abnormal response frequency of this sample is as follows; 24.0％ of boys, 23.8％ of girls, 22.5％ of the first-year students, and 26.9％ of the third-year students. There were significant difference among the grades. 14) The factors of distinctive correlation between the dimensions of SCL-90 and 16 factors were the father's negative attitude and depression, negative responses on teaching contents and anxiety, and smoking and hostility. In conclusion, mental health state of liberal highschool students on the whole showed worse than other normal groups. It had close terms with relation with their parents, schoolwork, smoking, teaching contents, the social surrounding, mass media, and the home environments. Thus I believe there need not only mental health education of students, training of teachers, counceling of parents, but also changes in teaching contents, and the improvement of educational system and the social surroundings under the national support.