• Title/Summary/Keyword: spatial aspects

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Topic Modeling and Sentiment Analysis of Twitter Discussions on COVID-19 from Spatial and Temporal Perspectives

  • AlAgha, Iyad
    • Journal of Information Science Theory and Practice
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    • v.9 no.1
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    • pp.35-53
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    • 2021
  • The study reported in this paper aimed to evaluate the topics and opinions of COVID-19 discussion found on Twitter. It performed topic modeling and sentiment analysis of tweets posted during the COVID-19 outbreak, and compared these results over space and time. In addition, by covering a more recent and a longer period of the pandemic timeline, several patterns not previously reported in the literature were revealed. Author-pooled Latent Dirichlet Allocation (LDA) was used to generate twenty topics that discuss different aspects related to the pandemic. Time-series analysis of the distribution of tweets over topics was performed to explore how the discussion on each topic changed over time, and the potential reasons behind the change. In addition, spatial analysis of topics was performed by comparing the percentage of tweets in each topic among top tweeting countries. Afterward, sentiment analysis of tweets was performed at both temporal and spatial levels. Our intention was to analyze how the sentiment differs between countries and in response to certain events. The performance of the topic model was assessed by being compared with other alternative topic modeling techniques. The topic coherence was measured for the different techniques while changing the number of topics. Results showed that the pooling by author before performing LDA significantly improved the produced topic models.

Ergo design on the automobile display and control (자동차의 표시장치 및 조종장치에 대한 Ergo Design)

  • 신학수
    • Journal of the Ergonomics Society of Korea
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    • v.5 no.2
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    • pp.33-36
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    • 1986
  • Compatiblity is a very generalized concept that has substantial applicablity to various aspects of human factors. It refers to the spatial movement, or conceptual relationships of stimuli and of responses, individually or in combination, which are consistent with human expectations. In this paper, first, several remarks which should be considered in designing the visual display and control of automobile are considered. Also, two advanced designs of visual display and control are suggested based on the compatibility principles.

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Geospatial Analysis and Modeling in Korea: A Literature Review (한국의 지리공간분석 및 모델링 연구)

  • Lee, Sang-Il;Kim, Kam-Young
    • Journal of the Korean Geographical Society
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    • v.47 no.4
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    • pp.606-624
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    • 2012
  • The main objective of this paper is to provide an adequate and comprehensive review of what has been done in South Korea in the field of geospatial analysis and modeling. This review focuses on spatial data analysis and spatial statistics, spatial optimization, and geosimulation among various aspects of the field. It is recognized that geospatial analysis and modeling in South Korea got through the initial stage during the 1990s when computer and analytical cartography and GIS were introduced, moved to the growth stage during the first decade of the $21^{st}$ century when there was a surge of relevant researches, and now is heading for its maturity stage. In spatial data analysis and spatial statistics, various topics have been addressed for spatial point pattern data, areal data, geostatistical data, and spatial interaction data. In spatial optimization, modeling and applications related to facility location problems, districting problems, and routing problems have been mostly researched. Finally, in geosimulation, while most of research has focused on cellular automata, studies on agent-based model and simulation are in beginning stage. Among all these works, some have fostered methodological advances beyond simple applications of the standard techniques.

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Application of Spatial Autocorrelation for the Spatial Distribution Pattern Analysis of Marine Environment - Case of Gwangyang Bay - (해양환경 공간분포 패턴 분석을 위한 공간자기상관 적용 연구 - 광양만을 사례 지역으로 -)

  • Choi, Hyun-Woo;Kim, Kye-Hyun;Lee, Chul-Yong
    • Journal of the Korean Association of Geographic Information Studies
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    • v.10 no.4
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    • pp.60-74
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    • 2007
  • For quantitative analysis of spatio-temporal distribution pattern on marine environment, spatial autocorrelation statistics on the both global and local aspects was applied to the observed data obtained from Gwangyang Bay in South Sea of Korea. Global indexes such as Moran's I and General G were used for understanding environmental distribution pattern in the whole study area. LISAs (local indicators of spatial association) such as Moran's I ($I_i$) and $G_i{^*}$ were considered to find similarity between a target feature and its neighborhood features and to detect hot spot and/or cold spot. Additionally, the significance test on clustered patterns by Z-scores was carried out. Statistical results showed variations of spatial patterns quantitatively in the whole year. Then all of general water quality, nutrients, chlorophyll-a and phytoplankton had strong clustered pattern in summer. When global indexes showed strong clustered pattern, the front region with a negative $I_i$ which means a strong spatial variation was observed. Also, when global indexes showed random pattern, hot spot and/or cold spot were/was found in the small local region with a local index $G_i{^*}$. Therefore, global indexes were useful for observing the strength and time series variations of clustered patterns in the whole study area, and local indexes were useful for tracing the location of hot spot and/or cold spot. Quantification of both spatial distribution pattern and clustering characteristics may play an important role to understand marine environment in depth and to find the reasons for spatial pattern.

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A Study on the Construction of Housing Geospatial Information for the Integrated use of Housing Supply Model (주택공급모형과의 연계활용을 위한 주택공간정보 구축방안 연구)

  • Choi, Jun Young;Kim, Taek Geun
    • Spatial Information Research
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    • v.20 no.6
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    • pp.1-11
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    • 2012
  • To solve the housing supply problems which are combined with economic, social, environmental and urban spatial structural aspects, it is needed to analyze housing supply based on the analysis model. This study aims to draw the construction of the housing geospatial information for housing supply model. For these purposes, we construct the housing geospatial information and draw case studies on information utilization based on the precedent studies and relevant systems about housing geospatial information. From the result, we construct the geospatial information according to spatial unit and draw standardization of connected information between housing supply information and housing geospatial information. Also we found that it is essential to use a building and parcel level housing geospatial information for housing supply. In the future, it will be needed to construct the housing supply information from qualitative aspect for dwelling and to establish a utilization strategy.

A Study on the Changing Roles of Cadastral Organizations to Comply with Environmental Changes (환경변화에 따른 지적기관의 역할 변화에 대한 고찰)

  • Oh, Yi-Kyun;Park, Jong-Cheul
    • Journal of Cadastre & Land InformatiX
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    • v.44 no.2
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    • pp.59-72
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    • 2014
  • In this paper the key drivers change for cadastral organizations have been presented according to the following aspects; Geo-ICT development including positioning technology, government's public organization innovation policy, cadastral market opening pressure and decreasing of cadastral survey work. It was confirmed that the role of cadastral organization has to be changed from the conducting cadastral survey organization to the spatial information provision organization. Eventually it should take a role to realize Spatially Enabled Society(SES) which is fundamental for national development and upgrading quality of life in the society. From the case study of international cadastral organization, cadastral organization should take core responsibility for the Nation Spatial Data Infrastructure(NSDI) and meeting the future costumers requirements through technical developments and organization's innovation efforts.

An Analysis of the Spatial Range of Environmental Impact Assessment(EIA) - Focusing on Landscape Ecological Aspects - (환경영향평가대상의 공간적 평가범위 설정에 관한 연구 - 경관생태학적 측면에서 -)

  • Oh, Kyushik;Kim, Hee-Ju;Lee, Dong-Kun
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.12 no.3
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    • pp.130-141
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    • 2009
  • The spatial range of EIA is mainly related to landscape ecological factors such as topography, geology, animals, and plants. Problems were detected involved land, soil, noise, oscillation, the atmosphere, animals, and plants in the natural-environment. First of all, the current EIA lacks explicit spatial ranges and sections in terms of scientific exactitude and objectivity for assessment. Secondly, there are overlapping influence-area problems resulting in cumulative impacts of unit developments that accumulate. Finally, some developments have no regard for ecological and conservational value in relation to determining which effect ecological stability, and which should be regarded as Regional Ecological Resources. Therefore, this study suggests that EIA should be improved in the following manner. First, the standard classification of landscape unit for analysis should be established 10 regulate each spatial range on a wide-landscape scale. Secondly, the impacts resulting from the interaction of overlapping influence-area developments between individual development should be assessed. Third, Minimization of the of the environmental effects is needed by applying the cumulative effects to the influence-area where developments occur in the same time or in a sequence. Fourth, individual characteristics of landscape elements such as roads, rivers, and green networks need to be considered separately in the analysis. Finally, regional ecological habitats should be included in the analysis in order to achieve stable ecosystems.

DOES LACK OF TOPOGRAPHIC MAPS LIMIT GEO-SPATIAL HYDROLOGY ANALYSYS?

  • Gangodagamage, Chandana;Flugel, Wolfgang;Turrel, Dr.Hagh
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.82-84
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    • 2003
  • Watershed boundaries and flow paths within the watershed are the most important factors required in watershed analysis. Most often the derivation of watershed boundaries and stream network and flow paths is based on topographical maps but spatial variation of flow direction is not clearly understandable using this method. Water resources projects currently use 1: 50, 000-scale ground survey or aerial photography-based topographical maps to derive watershed boundary and stream network. In basins, where these maps are not available or not accessible it creates a real barrier to watershed geo-spatial analysis. Such situations require the use of global datasets, like GTOPO30. Global data sets like ETOPO5, GTOPO30 are the only data sets, which can be used to derive basin boundaries and stream network and other terrain variations like slope aspects and flow direction and flow accumulation of the watershed in the absence of topographic maps. Approximately 1-km grid-based GTOPO 30 data sets can derive better outputs for larger basins, but they fail in flat areas like the Karkheh basin in Iran and the Amudarya in Uzbekistan. A new window in geo-spatial hydrology has opened after the launching of the space-borne satellite stereo pair of the Terra ASTER sensor. ASTER data sets are available at very low cost for most areas of the world and global coverage is expected within the next four years. The DEM generated from ASTER data has a reasonably good accuracy, which can be used effectively for hydrology application, even in small basins. This paper demonstrates the use of stereo pairs in the generation of ASTER DEMs, the application of ASTER DEM for watershed boundary delineation, sub-watershed delineation and explores the possibility of understanding the drainage flow paths in irrigation command areas. All the ASTER derived products were compared with GTOPO and 1:50,000-based topographic map products and this comparison showed that ASTER stereo pairs can derive very good data sets for all the basins with good spatial variation, which are equal in quality to 1:50,000 scale maps-based products.

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Korean Red Ginseng extract attenuates alcohol-induced addictive responses and cognitive impairments by alleviating neuroinflammation

  • Hee Jin Kim;Min Yeong Lee;Gyu Ri Kim;Hyun Jun Lee;Leandro Val Sayson;Darlene Mae D. Ortiz;Jae Hoon Cheong;Mikyung Kim
    • Journal of Ginseng Research
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    • v.47 no.4
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    • pp.583-592
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    • 2023
  • Background: Alcohol is one of the most commonly used psychoactive drugs. Due to its addictive characteristics, many people struggle with the side effects of alcohol. Korean Red Ginseng (KRG) is a traditional herbal medicine that is widely used to treat various health problems. However, the effects and mechanisms of KRG in alcohol-induced responses remain unclear. Therefore, the purpose of this study was to investigate the effects of KRG in alcohol-induced responses. Methods: We investigated two aspects: alcohol-induced addictive responses and spatial working memory impairments. To determine the effects of KRG in alcohol-induced addictive responses, we performed conditioned place preference tests and withdrawal symptom observations. To assess the effects of KRG in alcohol-induced spatial working memory impairment, Y-maze, Barnes maze, and novel object recognition tests were performed using mice after repeated alcohol and KRG exposure. To investigate the potential mechanism of KRG activity, gas chromatography-mass spectrometry and western blot analysis were performed. Results: KRG-treated mice showed dose-dependent restoration of impaired spatial working memory following repeated alcohol exposure. Furthermore, withdrawal symptoms to alcohol were reduced in mice treated with KRG and alcohol. The PKA-CREB signaling pathway was activated after alcohol administration, which was reduced by KRG. However, the levels of inflammatory cytokines were increased by alcohol and decreased by KRG. Conclusion: Taken together, KRG may alleviate alcohol-induced spatial working memory impairments and addictive responses through anti-neuroinflammatory activity rather than through the PKA-CREB signaling pathway.

Study on Relationship Between Spatial-Perceptual Ability and Driving-Related Situation Awareness (공간지각 능력에 따른 운전-관련 상황의 재인 및 예측에 관한 연구)

  • Bia Kim ;Jaesik Lee
    • Korean Journal of Culture and Social Issue
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    • v.11 no.4
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    • pp.83-95
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    • 2005
  • The purpose of the present study was to investigate the relationship between spatial-erceptual ability and several aspects of driving-related situation awareness(in particular, recognition and prediction). Video clips of real driving were used in both recognition and prediction tasks, and the digit calculation task during driving the simulator was required as the integration task of recognition and prediction. The results showed that the subjects of higher spatial-perceptual ability performed better in recognition task, especially in terms of sensitivity measured in d'(as signal detection theory), prediction task, and digits calculation performance than those of lower spatial-perceptual ability.