• Sleep Medicine and Psychophysiology
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• v.4 no.2
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• pp.164-171
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• 1997

Introduction : Periodic limb movement disorder (PLMD) is shown to common in patients with OSA and may become evident or worsened when treated with nasal continuous positive airway pressure (CPAP). Whether this is due to im proved sleep continuity. adverse nocturnal body positioning, uncovered by CPAP, or due to the CPAP stimulus is still debat-ed. We hypothesized that the increase in PLM activity following CPAP is associated with more supine-sleeping tendencies when being treated with CPAP. In the present work, we compared differences in the PLMD index (PLMI) and sleeping position of patients with sleep disordered breathing before and after CPAP treatment. Method : We studied 16 patients (mean age 46 yr, 9M, 7F) with OSA (11 patients) or UARS (5 patients) who either had PLMD on initial polysomnogram (baseline PSG) or on nasal CPAP trial (CPAP PSG). All periodic leg movements were scored on anterior tibialis EMG during sleep according to standard criteria (net duration; 0.5-5.0 seconds, intervals; 4-90 seconds. 4 consecutive movements). Paired t-tests compared PLMD index (PLMI), PLMD-related arousal index (PLMD-ArI), respiratory disturbance index (RDI), and supine sleeping position spent with baseline PSG and CPAP PSG. Results : Ten patients (63%) on baseline PSG and fifteen patients (94%) on CPAP PSG had documented PLMD ($PLMI{\ge}5$) respectively with significant increase on CPAP PSG(p<0.05). Ten patients showed the emergence (6/10 patients) or substantial worsening (4/10 patients) of PLMD during CPAP trial. Mean CPAP pressure was $7.6{\pm}1.8\;cmH_2O$. PLMI tended to increase from baseline PSG to CPAP PSG, and significantly increase when excluding 2 outlier (baseline PSG, $19.0{\pm}25.8/hr$ vs CPAP PSG, $29.9{\pm}12.5/hr$, p<0.1). PLMD-ArI showed no significant change, but a significant decrease was detected when excluding 2 outlier (p<0.1). There was no significant sleeping positional difference (supine vs non-supine) on baseline PSG, but significantly more supine position (supine vs non-supine, p<0.05) on CPAP PSG. There was no significant difference in PLMI during supine-sleeping and nonsupine-sleeping position on both of baseline PSG and CPAP PSG. There was also no significant difference in PLMI during supine-sleeping position between baseline PSG and CPAP PSG. With nasal CPAP, there was a highly significant reduction in the RDI (baseline PSG, $14.1{\pm}21.3/hr$ vs CPAP PSG, $2.7{\pm}3.9/hr$, p<0.05). Conclusion : This preliminary data confirms previous findings that CPAP is a very effective treatment for OSA, and that PLMD is developed or worsened with treatment by CPAP. This data also indicates that supine-sleeping position is more common when being treated with CPAP. However, there was no clear evidence that supine position is the causal factor of increased PLMD with CPAP. It is, however, suggested that the relative movement limitation induced by CPAP treatment could be a contributory factor of PLMD.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.11
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• pp.85-94
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• 2018

This study aims to investigate how easy pedestrians get around within/through the "Apartment Complexes (AC), " a common style of high-rise multi-family housing in Korea. Over the past six decades, the AC has been the most conventional way to provide standardized housing efficiently to address the problems of the shortage of housing and the substandard housing, due to the explosion of urban population with the rapid industrialization. The AC is a huge chunk of homeogenous multi-family housing, mostly condos with decent infrastructure, including parks, pedestrian passages, schools, ect. Both in the new town development and urban renewal programs have utilized the advantages of the AC. Since the design principals of AC tend to adopt the "protective design" to prevent cars and pedestrians coming outside from passing it, it has been criticised for dissecting the continuity of socioeconomic context in neighborhoods. The neo-traditional planning urbanists, including Jane Jacobs, emphasize that smaller blocks and grid road newtworks are the key in improving social, cultural, and economic vitality of the neighborhoods, because these design concepts allow more pedestrians and different types of people to be mixed in a neighborhood. In this study, we first adopted objective measures for pedestrian accessibility and pedestrian efficiency. These measures were used to calculate the lengths of shortest paths from residential buildings to the edges of AC. We tested the difference in shortest paths between the current pedestrian networks of AC and hypothetical grid networks on the AC, and the relative difference is considered as the pedestrian efficiency, using the network analysis function of Geographic Information Systems (GIS) and Python programming. We found from the randomly selected 30 ACs that the existing non-grid road networks in ACs are worse than the hypothesized grid networks, in terms of pedestrian efficiency. In average, pedestrians in AC with the conventional road networks have to walk than 25%, 26%, and 27% longer than the networks of $125{\times}45m$, $100{\times}45m$, and $75{\times}45m$, respectively. With the t-test analysis, we found the pedestrian efficiency of AC with the conventional network is lower than grid-networks. Many new urbanists stress, easiness of walking is one of the most import elements for community building and social bonds. With the findings from the objective measures of pedestrian accessibility and efficiency, the AC would have limitations to attract people outside into the AC itself, which would increase dis-connectivity with adjacent areas.

• Journal of the Korea Society of Computer and Information
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• v.28 no.10
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• pp.85-92
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• 2023

In this paper, we propose a method for automatically generating story-based abbreviated summaries from long-form dramas and movies. From the shooting stage, the basic premise was to compose a frame with illusion of depth considering the golden division as well as focus on the object of interest to focus the viewer's attention in terms of content delivery. To consider how to extract the appropriate frames for this purpose, we utilized elemental techniques that have been utilized in previous work on scene and shot detection, as well as work on identifying focus-related blur. After converting the videos shared on YouTube to frame-by-frame, we divided them into a entire frame and three partial regions for feature extraction, and calculated the results of applying Laplacian operator and FFT to each region to choose the FFT with relative consistency and robustness. By comparing the calculated values for the entire frame with the calculated values for the three regions, the target frames were selected based on the condition that relatively sharp regions could be identified. Based on the selected results, the final frames were extracted by combining the results of an offline change point detection method to ensure the continuity of the frames within the shot, and an edit decision list was constructed to produce an abbreviated summary of 62.77% of the footage with F1-Score of 75.9%

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.33 no.2
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• pp.67-77
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• 2015

The purpose of this paper is to draw historic valuable resources to conserve through the analysis about the preservation status of historic urban environment in Suwon Hwaseong Fortress. As for the conservation of urban environment, it is important to protect the resources showing historical continuity and to manage the resources remaining characteristics of place, the analysis of the preservation status is focused on the perspective of preservation of physical form and land use. This paper makes progress through three phases. First, in order to understand urban environment in Hwaseong Fortress overall, it compares land registration original map in 1911 to current map in 2014 by the four items of topography, water environment, streets and sites. Next, changes of four items in urban environment have been reviewed further by the research of maps, relative literatures, field survey and interview, and are classified according to the criteria of preservation-partially preservation-disappearance. After analysing preservation status, valuable urban historic cultural resources are drawn separately by being preserved continually and by being preserved partially but remaining characteristics of place. As a result, natural factors of topography and waterway and urban factor of streets are remained considerably preserved. And even if these factors are changed, the ground environment features support to understand historic urban context. Second, as preservation of topography, water environment, streets and sites are closely related to each other, integrated conservation frameworks are needed to enhance urban historic landscape. Third, modern historic resources in Hwaseong are remained unchanged and thus it is necessary to understand urban historic environment by the layers of various times besides Joseon Dynasty period. Fourth, historic sites and streets which had been preserved through urban development process are destroyed by recent historic cultural restoration policies, therefore urban historic resources worthy of conservation should be treated prudently.

• Korean Journal of Environmental Biology
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• v.30 no.1
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• pp.15-25
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• 2012

From April to November 2009, we performed field investigation to survey the characteristics of fish fauna and fish community structure inhabited in Yongdam reservoir in the upper Geumgang, which is changed into flat-water zone from flow-water zone by blocking the continuity by the gigantic submerged weir built in the upstream of Geumgang. 15 species belonging to 8 families were collected from natural habitat (St. 1) where its natural characteristics is well preserved, and 11 species were korean endemic fish species. 24 species belonging to 10 families were collected at the down region of Yongdam dam (St. 3), which might be affected by the change of water environment due to the dam, and 11 species were korean endemic fish species. On the other hand, 20 species belonging to 7 families were collected inside Yongdam reservoir (St. 2) which is changed into flat-water zone from flow-water zone by the dam reservoir, and 6 species were korean endemic fish species. In the dam reservoir, due to Yongdam dam built in the upper Geumgang, the original flow-water zone fish such as $Acheilognathus$ $koreensis$, $Pseudopungtungia$ $nigra$, $Coreoleuciscus$ $splendidus$, and $Gobiobotia$ $macrocephala$ were disappeared, and instead, the kinds of fish habitating in the flat-water zone tend to increase rapidly, such as $Carassius$ $auratus$, $Opsarichthys$ $uncirostris$ $amurensis$, $Hemiculter$ $eigenmanni$, $Zacco$ $platypus$, and $Lepomis$ $macrochirus$. Relative abundance of the insective fish was 66.7% at St. 1, 40.0% at St. 2, and 54.2% at St. 3. In order to preserve endemic fish species and aquatic ecosystem, it is desirable to minimize the artificial installation in the upper river, such as a large scale dam which can affect the habitat and if inevitable, it is required to prepare preservation measures when building facilities.

• Korean Journal of Remote Sensing
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• v.37 no.5_2
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• pp.1281-1293
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• 2021

The recent launch of the GOCI-II enables South Korea to have the world's first capability in deriving the ocean color data at geostationary satellite orbit for about 20 years. It is necessary to develop a consistent long-term ocean color time-series spanning GOCI to GOCI-II mission and improve the accuracy through validation using in situ data. To assess the GOCI-II's early mission performance, the objective of this study is to compare the GOCI-II Chlorophyll-a concentration (Chl-a), Colored Dissolved Organic Matter (CDOM), and remote sensing reflectances (R_rs) through comparison with the GOCI data. Overall, the distribution of GOCI-II Chl-a corresponds with that of the GOCI over the Yellow Sea, Korea Strait, and the Ulleung Basin. In particular, a smaller RMSE value (0.07) between GOCI and GOCI-II over the summer Ulleung Basin confirms the GOCI-II data's reliability. However, despite the excellent correlation, the GOCI-II tends to overestimate Chl-a than the GOCI over the Yellow Sea and Korea Strait. The similar over-estimation bias of the GOCI-II is also notable in CDOM. Whereas no significant bias or error is found for R_rs at 490 nm and 550 nm (RMSE~0), the underestimation of R_rs at 443 nm contributes to the overestimation of GOCI-II Chl-a and CDOM over the Yellow Sea and the Korea Strait. Also, we show over-estimation of GOCI-II R_rs at 660 nm relative to GOCI to cause a possible bias in Total suspended sediment. In conclusion, this study confirms the initial reliability of the GOCI-II ocean color products, and upcoming update of GOCI-II radiometric calibration will lessen the inconsistency between GOCI and GOCI-II ocean color products.

• Sleep Medicine and Psychophysiology
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• v.26 no.1
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• pp.44-48
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• 2019

Objectives: Insomnia is one of the most prevalent sleep disorders. Recent studies suggest that cognitive and physical arousal play an important role in the generation of primary insomnia. Studies have also shown that information processing disorders due to cortical hyperactivity might interfere with normal sleep onset and sleep continuity. Therefore, focusing on central nervous system arousal and normalizing the information process have become current topics of interest. It has been well known that neurofeedback can reduce the brain hyperarousal by modulating patients' brain waves during a sequence of behavior therapy. The purpose of this study was to investigate effects of neurofeedback therapy on electroencephalography (EEG) characteristics in patients with primary insomnia. Methods: Thirteen subjects who met the criteria for an insomnia diagnosis and 14 control subjects who were matched on sex and age were included. Neurofeedback and sham treatments were performed in a random order for 30 minutes, respectively. EEG spectral power analyses were performed to quantify effects of the neurofeedback therapy on brain wave forms. Results: In patients with primary insomnia, relative spectral theta and sigma power during a therapeutic neurofeedback session were significantly lower than during a sham session ($13.9{\pm}2.6$ vs. $12.2{\pm}3.8$ and $3.6{\pm}0.9$ vs. $3.2{\pm}1.0$ in %, respectively; p < 0.05). There were no statistically significant changes in other EEG spectral bands. Conclusion: For the first time in Korea, EEG spectral power in the theta band was found to increase when a neurofeedback session was applied to patients with insomnia. This outcome might provide some insight into new interventions for improving sleep onset. However, the treatment response of insomniacs was not precisely evaluated due to limitations of the current pilot study, which requires follow-up studies with larger samples in the future.

• Asia pacific journal of information systems
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• v.20 no.1
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• pp.141-170
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• 2010

User created content (UCC) is created and shared by common users on line. From the user's perspective, the increase of UCCs has led to an expansion of alternative means of communications, while from the business perspective UCCs have formed an environment in which an abundant amount of new contents can be produced. Despite outward quantitative growth, however, many aspects of UCCs do not meet the expectations of general users in terms of quality, and this can be observed through pirated contents and user-copied contents. The purpose of this research is to investigate effective methods for fostering production of creative user-generated content. This study proposes two core elements, namely, reward and motivation, which are believed to enhance content creativity as well as the mediating factor and users' committement, which will be effective for bridging the increasing motivation and content creativity. Based on this perspective, this research takes an in-depth look at issues related to constructing the dimensions of reward and motivation in UCC services for creative content product, which are identified in three phases. First, three dimensions of rewards have been proposed: task dimension, social dimension, and organizational dimention. The task dimension rewards are related to the inherent characteristics of a task such as writing blog articles and pasting photos. Four concrete ways of providing task-related rewards in UCC environments are suggested in this study, which include skill variety, task significance, task identity, and autonomy. The social dimensioni rewards are related to the connected relationships among users. The organizational dimension consists of monetary payoff and recognition from others. Second, the two types of motivations are suggested to be affected by the diverse rewards schemes: intrinsic motivation and extrinsic motivation. Intrinsic motivation occurs when people create new UCC contents for its' own sake, whereas extrinsic motivation occurs when people create new contents for other purposes such as fame and money. Third, commitments are suggested to work as important mediating variables between motivation and content creativity. We believe commitments are especially important in online environments because they have been found to exert stronger impacts on the Internet users than other relevant factors do. Two types of commitments are suggested in this study: emotional commitment and continuity commitment. Finally, content creativity is proposed as the final dependent variable in this study. We provide a systematic method to measure the creativity of UCC content based on the prior studies in creativity measurement. The method includes expert evaluation of blog pages posted by the Internet users. In order to test the theoretical model of our study, 133 active blog users were recruited to participate in a group discussion as well as a survey. They were asked to fill out a questionnaire on their commitment, motivation and rewards of creating UCC contents. At the same time, their creativity was measured by independent experts using Torrance Tests of Creative Thinking. Finally, two independent users visited the study participants' blog pages and evaluated their content creativity using the Creative Products Semantic Scale. All the data were compiled and analyzed through structural equation modeling. We first conducted a confirmatory factor analysis to validate the measurement model of our research. It was found that measures used in our study satisfied the requirement of reliability, convergent validity as well as discriminant validity. Given the fact that our measurement model is valid and reliable, we proceeded to conduct a structural model analysis. The results indicated that all the variables in our model had higher than necessary explanatory powers in terms of R-square values. The study results identified several important reward shemes. First of all, skill variety, task importance, task identity, and automony were all found to have significant influences on the intrinsic motivation of creating UCC contents. Also, the relationship with other users was found to have strong influences upon both intrinsic and extrinsic motivation. Finally, the opportunity to get recognition for their UCC work was found to have a significant impact on the extrinsic motivation of UCC users. However, different from our expectation, monetary compensation was found not to have a significant impact on the extrinsic motivation. It was also found that commitment was an important mediating factor in UCC environment between motivation and content creativity. A more fully mediating model was found to have the highest explanation power compared to no-mediation or partially mediated models. This paper ends with implications of the study results. First, from the theoretical perspective this study proposes and empirically validates the commitment as an important mediating factor between motivation and content creativity. This result reflects the characteristics of online environment in which the UCC creation activities occur voluntarily. Second, from the practical perspective this study proposes several concrete reward factors that are germane to the UCC environment, and their effectiveness to the content creativity is estimated. In addition to the quantitive results of relative importance of the reward factrs, this study also proposes concrete ways to provide the rewards in the UCC environment based on the FGI data that are collected after our participants finish asnwering survey questions. Finally, from the methodological perspective, this study suggests and implements a way to measure the UCC content creativity independently from the content generators' creativity, which can be used later by future research on UCC creativity. In sum, this study proposes and validates important reward features and their relations to the motivation, commitment, and the content creativity in UCC environment, which is believed to be one of the most important factors for the success of UCC and Web 2.0. As such, this study can provide significant theoretical as well as practical bases for fostering creativity in UCC contents.