• Journal of Korea Water Resources Association
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• v.57 no.8
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• pp.509-518
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• 2024

Flash drought is a rapid-onset drought that occurs rapidly over a short period due to abrupt changes in meteorological and environmental factors. In this study, we utilized satellite-based soil moisture product from the Advanced Microwave Scanning Radiometer-2(AMSR2) ascending X-band to calculate the weekly Flash Drought Intensity Index (FDII). We also analyzed the characteristics of flash droughts on the Korean Peninsula over a 10-year period from 2013 to 2022. The analysis of monthly spatial distribution patterns of the irrigation period across the Korean Peninsula revealed significant variations. In North Korea (NK), a substantial increase in the rate of intensification (FD_INT) was observed due to the rapid depletion of soil moisture, whereas South Korea (SK) experienced a significant increase in drought severity (DRO_SEV). Additionally, regional time series analysis revealed that both FD_INT and DRO_SEV were significantly high in the Gangwon province of both NK and SK. The estimation of probability density by region revealed a clear difference in FD_INT between NK and SK, with SK showing a higher probability of severe drought occurrence primarily due to the high values of DRO_SEV. As a result, it is inferred that the occurrence frequency and damage of flash droughts in NK are higher than those in SK, as indicated by the higher density of large FDII values in the NK region. We analyzed the correlation between DRO_SEV and the Evaporative Stress Index (ESI) across the Korean Peninsula and confirmed a positive correlation ranging from 0.4 to 0.6. It is concluded that analyzing overall drought conditions through the average drought severity holds high utility. These findings are expected to contribute to understanding the characteristics of flash droughts on the Korean Peninsula and formulating post-event response plans.

• Journal of the Korean Society of Radiology
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• v.10 no.7
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• pp.477-482
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• 2016

This study is tried to determine whether the management of medical radiation is well handled by comparison the guidelines of KFDA(korea food & drug administration) with analysis of dose indicator in mammography. As a method, it is analysed that kVp, exposure time, mAs, compressed breast thickness, average glandular dose and body mass index that were classified in the examination of both breasts by CC(cranio-caudal) and MLO(medio-lateral oblique) with EMR(electronic medical record) and dose report that were sent to the PACS(picture archiving communication system). As a result, in the site inspection according to the age, Compressed breast thickness in CC and MLO were the thickest of 45.6 mm and 49.6 mm in the 50-59 year old respectively. In the overall average compressed breast thickness, CC were 44.2 mm and MLO were 48.9 mm. MLO has more thick by 4.7 mm. In average glandular dose, CC were 1.05 mGy and MLO were 1.14 mGy. MLO has higher by 0.09 mGy than CC. As the compressed breast thickness increases 10mm, CC and MLO increases 0.15 mGy and 0.17 mGy respectively. When it was compared with the average glandular dose of 1.16 mGy per 1 film presented by KFDA, CC was showed 1.05 mGy. However, the 60 mm or more was found to exceed a 1.30 mGy. Also, As the compressed breast thickness was higher, body mass index showed high score. And in the case of 25 or more in the obese body index according to body mass index, it was showed obesity in case of the compressed breast thickness was more than 50mm.

• Neonatal Medicine
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• v.18 no.1
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• pp.117-123
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• 2011

Purpose: Congenital intrahepatic portosystemic shunts are rare disease and clinically asymptomatic shunts may be detected by chance on ultrasonogram before and after birth. We studied clinical course, treatment and prognosis of congenital intrahepatic portosystemic shunt at prenatal or neonatal period. Methods: Medical records of 8 patients which were diagnosed in intrahepatic portosystemic shunt in Cheil General Hospital from 2006 through 2010 were reviewed retrospectively. Results: Eight patients with congenital intrahepatic portosystemic shunts were identified. Six patients were diagnosed at prenatal radiological screening, including three cases of intrauterine growth restriction and two cases of preterm baby. One case with increased serum ammonia underwent coil embolization. In four cases including one case that presented elevated direct bilirubin, shunts were closed spontaneously within 11th month after birth. Two patients were diagnosed on abdominal sonogram after birth because of elevated direct hyperbilirubinemia, all of whom presented intrauterine growth restriction. Closure of shunts was confirmed during 4th month to 6th month. Conclusion: Congenital intrahepatic portosystemic shunts are clinically asymptomatic mostly and spontaneous closure is expected within 2 years age. But occasionally they have severe complication, so clinical and radiological observation is needed. Specially in cases of intrauterine growth retardation without evident cause, the possible diagnosis of congenital intrahepatic portosystemic shunts should be considered and prenatal and postnatal examination should be performed. When prenatal diagnosis is made, fetal wellbeing should be monitored periodically until spontaneous closure of shunts.

• Journal of The Korean Association For Science Education
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• v.22 no.4
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• pp.779-795
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• 2002

Internet, a world wide network of computers, is considered as a sea of information because it allows people to share information beyond the barriors of time and space. However, in spite of the unmeasurable potential applications of the internet, its use in the field of biology education has been extremely limited mainly due to the scarcity of good biology-related sites. In order to provide useful guidelines for constructing user-friendly study sites, which can help high school students with different intellectual levels to study biology, comparative studies were performed on selected educational sites. Initially, hundreds of related sites were examined, and, subsequently, four distinct sites were selected not only because they are well organized, but also because each is unique in its contents. Also, a survey was carried out against the users of each site. The survey results indicated that the high school students regard the web-based biology study tools as effective teaching methods although there might be some bias in criteria for selecting target sites. In addition to the detailed biology topics and the related biology informations, multimedia data including pictures, animations and movies are found to be one of the important ingredients for desirable biology study sites. Thus, the inclusion of multimedia components should also be considered when developing a systematic biology study site. Overall, the role of the cyber space is expected to become more and more important. Since the development of the user-satisfied and self-guided sites require interdisciplinary collaborational efforts which should be made to promote extensive communication among teachers, education professionals, and computer engineers. Furthermore, the introduction of good biology study sites to the students by their teachers is also important factor for the successful web-based education.

• Journal of Korean Home Economics Education Association
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• v.21 no.2
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• pp.139-158
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• 2009

The purposes of this study are to develop cyber home study program on consumer life for youth in middle school students and to compare the learning effect of this program with that of teacher's off-line lecture in class. The contents of the middle school Home Economics. Technology textbooks was analyzed. Based on this analysis 4 cyber home study lesson plans on youth's consumer life were developed. The topics of lesson plan were as 'youth and consumer behavior', 'utilizing consumer information'. 'effective consumer choice', 'resolving consumer problems'. The cyber home study were composed of 5 steps which were 'guiding' $\rightarrow$ 'learning activities' $\rightarrow$ 'evaluation' $\rightarrow$ 'further study' $\rightarrow$ 'summery'. The second grade middle school students as an experimental group participated in cyber home study through on-line class. The control group of students who had same condition with the experimental group were taught by home economics teacher using traditional instructional methods in off-line class. After the experiment, the changes in consumer's attitudes and knowledge of both groups were analyzed using Analysis of Covariance. The significant improvements of consumer's attitudes and knowledge were found in both the experimental and control groups of students. However, the consumer's attitudes and knowledge of the students who were taught by the teacher in off-line class improved more than those of the students who studied using cyber home study program in on-line class. Thus, the following conclusion is made that the cyber home study could be one of the useful learning methods to aid traditional off-line teaching in class.

• Cartoon and Animation Studies
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• s.22
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• pp.81-97
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• 2011

The technology of 'Virtual Reality' has placed in advanced tools for human beings' joy and anger together with sorrow and pleasure in our generation. It has recently tried in a variety ways to use as an implication for treatment in the field of Cognitive Psychology. Especially, it widely approaches to human in terms of that a sense of reality in a virtual world through the five senses should reinterpret the meaning of cognition in the real world. Based on this paradigm shift, it allows for new treatment using the technology of virtual reality. A typical example is a field of Therapy in order to overcome panic disorder. It has advantages that in particular development of flexible interaction technologies in a virtual space can lead patients to experience psychological environments rather than physical one. the interaction technology provides environments in which users' five senses can be actively stimulated, it is very useful that information from the experiences in the virtual world allows people to learn through real experiences by renewing potential energies, advantages of Virtual Reality Therapy can be customized treatment by depending on symptoms in patients with panic disorder and are capable of differentiate application for the cure at each stage. It is to treat by leading patients to get accustomed to environments and situations in real world through care process with each symptom and stage. It is helpful that based on A Human-Sensibility Ergonomics, technologies like immersive virtual reality equipment, force-relative feedback and stereophonic sound, and like stimulating the sense of smell make people to induce experiences by stimulating human's five senses. There are many advantages of immersion in virtual world in that the phenomenon such as challenge, interaction, reality, illusion, and cooperation is expanded. As an application for therapy by growing such augmented reality, virtual space and sharing of data through the Internet and also inexpensive its availability have recently expanded the base. There are other benefits of Virtual Reality Therapy offering active interaction environments for cognitive experience which can provide appropriately adjusted environments for patients who are hard to overcome the real situation because of phobia. In addition to that it is safe and economical and patients' confidentiality is assured. Moreover, due to the principles of applying real-time navigation the Virtual Reality Therapy makes modification and supplementation easier and also it can reduce cybersickness because of the supply of Lenticular allowing people to see stereoscopy without eyeglasses, which makes sense of presence clearer. On top of that due to the development of interactive technologies, it is becoming close to sense of reality similar to real world by leading users to navigate by themselves and to operate objects in a virtual space. This paper will therefore examine, although it is of limited, characteristics of application of virtual reality technology based on A Human-Sensibility Ergonomics used for treatment for a disorder. this paper will analyse a range of its application and problems and it will suggest the future possibilities.

• Nuclear Medicine and Molecular Imaging
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• v.43 no.5
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• pp.386-394
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• 2009

Purpose: We aimed to assess the myocardial velocity on gated myocardial perfusion SPECT (gated MPS), to compare myocardial velocity between patients without coronary artery disease (CAD) and CAD patients and to assess the correlation of myocardial velocity and perfusion and wall thickening on CAD group. Materials and Methods: Seventeen patients without CAD (M:F=9:8, mean age $61.8{\pm}11.1$ yrs: group A) and thirty-nine patients with CAD (M:F=18:21, mean age $66.9{\pm}8.1$ yrs : group B) had undergone one-day adenosine stress gated MPS. In twenty segment model, 12 segments (except apical and basal segments) of each patient were included. We obtained systolic and diastolic gate ratio in left ventricular volume curve by eight frames per cardiac cycle on gated MPS. Using the systolic and diastolic gate ratio and R-R time of each patient, we obtained systolic and diastolic time ratio. The myocardial velocity was defined as wall thickening over systolic or diastolic time. Results: We presented normal range of myocardial velocities according segments and territories of coronary artery. The myocardial velocity of group B was significantly lower than group A (p=0.00). There was no significant difference between the myocardial velocity of group B with preserved EF and group A. The stress systolic velocity significantly correlated with regional myocardial perfusion in group B with preserved EF (p=0.00) as well as decreased EF (p=0.01). In group B, stress perfusion of segments which had decreased wall thickening and decreased myocardial velocity was significantly lower than segments which had decreased wall thickening and preserved myocardial velocity (p=0.01). Conclusion: The new functional index of velocity will be used as an useful of gated MPS.

• Korean Journal of Remote Sensing
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• v.37 no.5_3
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• pp.1361-1371
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• 2021

Among smart city services, the crime and disaster prevention sector accounted for the highest 24% in 2018. The most important platform for providing real-time situation information is CCTV (Closed-Circuit Television). Therefore, it is essential to create the actual CCTV surveillance coverage to maximize the usability of CCTV. However, the amount of CCTV installed in Korea exceeds one million units, including those operated by the local government, and manual identification of CCTV coverage is a time-consuming and inefficient process. This study proposed a method to efficiently construct CCTV's actual surveillance coverage and reduce the time required for the decision-maker to manage the situation. For this purpose, first, the exterior orientation parameters and focal lengths of the pre-installed CCTV cameras, which are difficult to access, were calculated using the point cloud data of the MMS (Mobile Mapping System), and the FOV (Field of View) was calculated accordingly. Second, using the FOV result calculated in the first step, CCTV's actual surveillance coverage area was constructed with 1 m, 2 m, 3 m, 5 m, and 10 m grid interval considering the occluded regions caused by the buildings. As a result of applying our approach to 5 CCTV images located in Uljin-gun, Gyeongsnagbuk-do the average re-projection error was about 9.31 pixels. The coordinate difference between calculated CCTV and location obtained from MMS was about 1.688 m on average. When the grid length was 3 m, the surveillance coverage calculated through our research matched the actual surveillance obtained from visual inspection with a minimum of 70.21% to a maximum of 93.82%.