• Journal of Ecology and Environment
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• v.44 no.2
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• pp.62-71
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• 2020

Understanding vegetation structure and the relationship with environmental factors has been crucial for restoration and conservation of riparian zones. In this study, we conducted field survey in a riparian zone of Namhan River in South Korea both before and after flooding in order to understand temporal and spatial variations of riparian vegetation. There were significant temporal and spatial variations in species composition, and distribution patterns of vegetation were different along a gradient of elevation above the water level. At low elevation, Zizania latifolia was dominant throughout the field survey periods, and Bidens frondosa began to grow late and dominated both in post-flooding 1 and 2. Prior to flooding, Scirpus radicans and Polygonum thunbergii were widely distributed at middle elevation, while Artemisia vulgaris, Phragmites australis, and Miscanthus sacchariflorus were dominant at high elevation. After flooding, P. thunbergii was dominant at middle elevation with most other species decreasing, and more invasive or pioneer plants, including Artemisia princeps, H. scandens, and Sicyos angulatus, were observed at high elevation. Species composition and distribution patterns were homogeneous at low elevation, whereas dynamic variations of vegetation were observed both temporally and spatially at higher elevations. Elevation and distance from the water front were the most principal factors governing vegetation structure. Furthermore, soil physicochemical properties were also found to determine species composition and distribution patterns. These results indicate that vegetation structure in the riparian zones is formed by the combined effects of hydrological regime and soil physicochemical properties, inherent characteristics of species, and interspecific competition. Understanding of temporal and spatial variations of riparian vegetation may provide useful insights into ecological restoration and conservation of the vegetation within the riparian zones.

• Journal of the Korean housing association
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• v.24 no.5
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• pp.49-56
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• 2013

The goal of this research is to explore quantitative and residential features and spatial patterns of two-person households to suggest policy implications for housing supply and development in Seoul. Major findings of this study are as follows. First, the number of two-person households has increased rapidly mainly due to the growth of the elderly and single-parent households. They are mainly composed of the elderly over 60s and the youth of 30s of householder age. They are less likely to have well-paying jobs, and thus more likely to suffer from poverty. They are also inclined to live in rental and small-sized residential units and spatial segregation between the youth and the elderly became serious. In addition, their residential area can be classified into four types: area adjacent to employment centers, hinterland of urban centers, affordable multi-family housing area and redeveloped apartment area. It is necessary to change the current housing policy directions to take changing population and household structure into consideration. Also, diversified housing strategies and programs should be prepared to consider various household types and their needs and demands. Place-based strategies for housing supply and development are needed in consideration of spatial patterns and locational attributes of two-person households. Attention needs to be paid to resolving the social issue of residential segregation between different generations.

• Journal of Information Technology Services
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• v.15 no.1
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• pp.245-253
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• 2016

Background in a novel is most important elements with characters and events, and means time, place and situation that characters appeared. Among the background, spatial background can help conveys topic of a novel. So, it may be helpful for choosing a novel that readers want to read. In this paper, we are targeting Korean historical novels. In case of English text, It can be recognize spatial background easily because it use upper and lower case and words used with the spatial information such as Bank, University and City. But, in case Korean text, it is difficult to recognize that spatial background because there is few information about usage of letter. In the previous studies, they use machine learning or dictionaries and rules to recognize about spatial information in text such as news and text messages. In this paper, we build a nation dictionaries that refer to information such as 'Korean history' and 'Google maps.' We Also propose a method for recognizing spatial background based on patterns of postposition in Korean sentences comparing to previous works. We are grasp using of postposition with spatial background because Korean characteristics. And we propose a method based on result of morpheme analyze and frequency in a novel text for raising accuracy about recognizing spatial background. The recognized spatial background can help readers to grasp the atmosphere of a novel and to understand the events and atmosphere through recognition of the spatial background of the scene that characters appeared.

• Proceedings of the KGS Conference
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• 2006.06a
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• pp.191-192
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• 2006

• Journal of the Korean Geographical Society
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• v.39
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• pp.59-78
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• 1989

• Proceedings of the Optical Society of Korea Conference
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• 1998.08a
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• pp.80-81
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• 1998

• Journal of the Korean Geographical Society
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• v.29
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• pp.37-47
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• 1984

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.49 no.6
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• pp.25-34
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• 2012

New calibration method for the near-field scanning (NFS) system is presented. The proposed calibration method consisted of a new near-field antenna (NFP) and newly devised patterns as circular patch patterns (CPPs) and meander patterns (MPs). The proposed patterns were used for improving spatial resolutions and simplifying a calibration procedure of the NFP compared to the conventional method defined in the IEC61967-3 and 6. Also, the effect of the length of NFPs on attenuation characteristics was investigated with length of 8mm and 30mm. For them, we designed and fabricated CPPs of diameter (D) = 20, 40, 60, and 100mm and MPs of various widths and spaces. We found the reverse relations between spatial resolutions and heights of measuring points by using simplified calibration procedure. The testing result shows that the spatial resolution of $120{\mu}m$ at height of $200{\mu}m$ was verified without complex correlation algorithms under 8GHz. For manufacturing cost all patterns and the NFP were realized with low-cost fabrication using PCB (FR-4) not by a conventional LTCC process. For verification of chip-level EMC from the results, near-field scanning system (NFSS) having step resolution of Sub-micron scale was produced and by using the proposed NFSS and proposed NFP measurement of chip shows accurately the shape of the resolution of $200{\mu}m$ patterns for securing a high level of chip-level EMC verification.

• Journal of the Economic Geographical Society of Korea
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• v.12 no.2
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• pp.179-194
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• 2009

The spatial distribution of crime incidences in urban neighborhoods is a reflection of their socio-economic environment and spatial inter-relations. Spatial interactions between offenders and victims lead to spatial autocorrelation of the crime incidences. The spatial autocorrelation among the incidences biases the interpretation of the ecological model in OLS framework. This research investigates residential crimes using residential burglaries and robberies occurred in the city of Columbus, Ohio, for 2000. In particular, the spatial distribution of incidence rates of residential crimes are accounted in OLS framework using eigenvectors, which reflect spatial dependence in crime patterns. Result presents that handling spatial autocorrelation enhanced model estimation, and both economic deprivation and crime opportunity are turned out significant in estimating residential crime rates.

• Journal of Cadastre & Land InformatiX
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• v.46 no.2
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• pp.269-281
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• 2016

The process of spatial big data, such as social media, is being paid more attention in the field of spatial information in recent years. This study, as an example of spatial big data analysis, analyzed the spatial and temporal distribution of Tweet data based on the location and time information. In addition, the characteristics of its spatial pattern by times were identified. Tweet data in Busan city are collected, processed, and analyzed to identify the characteristics of the temporal and spatial pattern. Then, the results of Tweet data analysis were compared with the characteristics of the land type. This study found that spatial pattern of tweeting in the city was associated with given time periods such as daytime and nighttime in both weekdays and weekends. The spatial distribution patterns of individual time periods were compared with the characteristics of the land for the spatially concentrated area. The results of this study showed that tweeted data would be related to different spatial distribution depending on the time, which potentially reflects the daily pattern and characteristics of the land type of urban area to some extent. This study presented the possible incorporation of social media data, e. g. Tweet data, into the field of spatial information. It is expected that there will be more advantage to use a variety of social media data in areas such as land planning and urban planning.