• Title/Summary/Keyword: thematic analysis

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Site Selection Model for Wetland Restoration and Creation for the Circulation of Water in a Newly-built Community (신도시 물순환체계 구축을 위한 습지조성 입지선정에 관한 연구)

  • Choi, Hee-Sun;Kim, Kwi-Gon
    • Journal of the Korean Institute of Landscape Architecture
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    • v.36 no.6
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    • pp.43-54
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    • 2009
  • This study attempted to develop a model for selecting sites for ecologically effective, multi-functional wetlands during the environmental and ecological planning stage, prior to land use Planning. This model was developed with an emphasis upon the creation of a water circulation system for a newly-created city, dispersing and retaining the run-off that is increased due to urbanization and securing spaces to create wetlands that can promote urban biodiversity. A series of Precesses for selecting sites for wetland restoration and creation - watershed analysis, selection of evaluation items, calculation of weights, reparation of thematic maps and synthesis - were incorporated into the model. Its potentials and limitations were examined by applying it to the recently-planned WiRae New Community Development Area, which is located in the Seoul metropolitan region. At the watershed analysis stage, the site was divided into 13 sub-catchment areas. Inflow to watersheds including the area was $3,020,765m^3$ Run-off before and after development is estimated as $1,901,969m^3$ and $1,970,735{\sim}2,039,502m^3$, respectively. The total storage capacity required in the development area amounts to $68,766{\sim}137,533m^3$. When thematic maps were overlapped during the selection stage for wetland sites, 13 sub-catchment areas were prioritized for wetland restoration and creation. The locations and areas for retaining run-off showed that various types of wetlands, including retaining wetlands (area wetlands), riverine wetlands (linear wetlands) and pond wetlands (point wetlands), can be created and that they can be systematically connected. By providing a basic framework for the water circulation system plan of an entire city, it may be used effectively in the space planning stage, such as planning an urban eco-network through integration with greet areas. In order to estimate reasonable run-off and create an adequate water circulation system however, a feedback process following land use planning is required. This study strived to promote urban changes in a positive direction while minimizing urban changes in negative forms.

A Study on Object-Based Image Analysis Methods for Land Cover Classification in Agricultural Areas (농촌지역 토지피복분류를 위한 객체기반 영상분석기법 연구)

  • Kim, Hyun-Ok;Yeom, Jong-Min
    • Journal of the Korean Association of Geographic Information Studies
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    • v.15 no.4
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    • pp.26-41
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    • 2012
  • It is necessary to manage, forecast and prepare agricultural production based on accurate and up-to-date information in order to cope with the climate change and its impacts such as global warming, floods and droughts. This study examined the applicability as well as challenges of the object-based image analysis method for developing a land cover image classification algorithm, which can support the fast thematic mapping of wide agricultural areas on a regional scale. In order to test the applicability of RapidEye's multi-temporal spectral information for differentiating agricultural land cover types, the integration of other GIS data was minimized. Under this circumstance, the land cover classification accuracy at the study area of Kimje ($1300km^2$) was 80.3%. The geometric resolution of RapidEye, 6.5m showed the possibility to derive the spatial features of agricultural land use generally cultivated on a small scale in Korea. The object-based image analysis method can realize the expert knowledge in various ways during the classification process, so that the application of spectral image information can be optimized. An additional advantage is that the already developed classification algorithm can be stored, edited with variables in detail with regard to analytical purpose, and may be applied to other images as well as other regions. However, the segmentation process, which is fundamental for the object-based image classification, often cannot be explained quantitatively. Therefore, it is necessary to draw the best results based on expert's empirical and scientific knowledge.

Analysis on the Sedimentary Environment Change Induced by Typhoon in the Sacheoncheon, Gangneung using Multi-temporal Remote Sensing Data (태풍 루사에 의한 강릉 사천천 주변 퇴적 환경 변화: 다중 시기 원격탐사 자료를 이용한 정보 분석)

  • Park, No-Wook;Jang, Dong-Ho;Chi, Kwang-Hoon
    • Journal of the Korean earth science society
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    • v.27 no.1
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    • pp.83-94
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    • 2006
  • The objective of this paper is to extract and analyze the sediment environment change information in the Sachencheon, Gangneung, Korea that was seriously damaged as a result of typhoon Rusa aftermath early in September, 2002 using multi-temporal remote sensing data. For the extraction of change information, an unsupervised approach based on the automatic determination of thresholding values was applied. As the change detection results, turbidity changes right after typhoon Rusa, the decrease of wetlands, the increase of dry sand and channel width and changes of relative level in the stream due to seasonal variation were observed. Sedimentation in the cultivated areas and restoration works also affected the change near the Sacheoncheon. In addition to the change detection analysis, several environmental thematic maps including microtopographic map, distributions of estimated amount of flood deposits and flood hazard landform classification map were generated by using remote sensing and field survey data. In conclusion, multi-temporal remote sensing data can be effectively used for natural hazard analysis and damage information extraction and specific data processing techniques for high-resolution remote sensing data should also be developed.

Evaluation of Basin-Specific Water Use through Development of Water Use Assessment Index (이수평가지수 개발을 통한 유역별 물이용 특성 평가)

  • Baeck, Seung Hyub;Choi, Si Jung
    • Journal of Wetlands Research
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    • v.15 no.3
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    • pp.367-380
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    • 2013
  • In this study, sub-indicators, and thematic mid-indexes to evaluate the water use characteristics were selected through historical data analysis and factor analysis, and consisted of the subject approach framework. And the integrated index was developed to evaluate water use characteristics of the watershed. Using developed index, the water use characteristics were assessed for 812 standard basins with the exception for North Korea using data of 1990 to 2007 from the relevant agencies. A sensitivity analysis is conducted for this study to determine the proper way through various normalization and weighting methods. To increase the objectivity of developed index, the history of the damage indicators are excluded in the analysis. In addition, in order to ensure its reliability, results from index with and without consideration of the damage history were compared. Also, the index is also applied to real data for 2008 Gangwon region to verify its field applicability. Through the validation process this index confirmed the adequacy for the indicators selection and calculation method. The results of this study were analyzed based on the spatial and time vulnerability of the basin's water use, which can be applied to various parts such as priority decision-making for water business or policy, mitigations for the vulnerable components of the basin, and supporting measures to establishment by providing relevant information about it.

GIS-based Spatial Integration and Statistical Analysis using Multiple Geoscience Data Sets : A Case Study for Mineral Potential Mapping (다중 지구과학자료를 이용한 GIS 기반 공간통합과 통계량 분석 : 광물 부존 예상도 작성을 위한 사례 연구)

  • 이기원;박노욱;권병두;지광훈
    • Korean Journal of Remote Sensing
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    • v.15 no.2
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    • pp.91-105
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    • 1999
  • Spatial data integration using multiple geo-based data sets has been regarded as one of the primary GIS application issues. As for this issue, several integration schemes have been developed as the perspectives of mathematical geology or geo-mathematics. However, research-based approaches for statistical/quantitative assessments between integrated layer and input layers are not fully considered yet. Related to this niche point, in this study, spatial data integration using multiple geoscientific data sets by known integration algorithms was primarily performed. For spatial integration by using raster-based GIS functionality, geological, geochemical, geophysical data sets, DEM-driven data sets and remotely sensed imagery data sets from the Ogdong area were utilized for geological thematic mapping related by mineral potential mapping. In addition, statistical/quantitative information extraction with respective to relationships among used data sets and/or between each data set and integrated layer was carried out, with the scope of multiple data fusion and schematic statistical assessment methodology. As for the spatial integration scheme, certainty factor (CF) estimation and principal component analysis (PCA) were applied. However, this study was not aimed at direct comparison of both methodologies; whereas, for the statistical/quantitative assessment between integrated layer and input layers, some statistical methodologies based on contingency table were focused. Especially, for the bias reduction, jackknife technique was also applied in PCA-based spatial integration. Through the statistic analyses with respect to the integration information in this case study, new information for relationships of integrated layer and input layers was extracted. In addition, influence effects of input data sets with respect to integrated layer were assessed. This kind of approach provides a decision-making information in the viewpoint of GIS and is also exploratory data analysis in conjunction with GIS and geoscientific application, especially handing spatial integration or data fusion with complex variable data sets.

Exploring the Research Trend Changes on Convergence Education of Before and After 2011 in Science Education (2011년 전후의 과학교육분야에서의 융합교육 연구동향의 변화 탐색)

  • Song, Youngwook;Paik, Seoung-Hey
    • Journal of The Korean Association For Science Education
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    • v.40 no.5
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    • pp.531-542
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    • 2020
  • The purpose of this study is to explore the research trend changes of convergence education since 2011 compared to the convergence education research that has been steadily continuing in science education. The trend in convergence education were investigated by comparing the number of publications, research subjects, research content, and topic linkages with previous studies, and using the network analysis method to check recent research trends. In the field of science education, the number of papers related to convergence education has been published more than 8.0% steadily, and it has been increasing since 2012, then decreasing again from 2015 and gradually increasing again from 2017. The subjects of study were high in elementary school students, while those in middle school, high school, and university students were low. While the number of in-service teachers increased, the number of pre-service teachers decreased, and the literature and public increased somewhat. In study content, effectiveness studies decreased, while development studies increased, and theoretical and perception studies appeared similar. In thematic linkage, the intra-science linkage was 23.9%, and the extra-science linkage was 76.1% and engineering/technology and art were high in extra-science linkage. In network analysis, elementary, science, STEAM, and program words have a high frequency of appearance and appear together with other words to lead the network. The educational implications of the research trend of convergence education will be more emphasized in the field of science education in the future, and in order to take root in the education field, research on secondary students should be more actively studied. In addition, it is necessary to move away from research on STEAM-centered program development and effects, and to increase research to establish the philosophical basis and theoretical of convergence education.

An Analysis of Forest Fire Occurrence Hazards by Changing Temperature and Humidity of Ten-day Intervals for 30 Years in Spring (우리나라의 봄철 순평년 온습도 변화에 따른 산불발생위험성 분석)

  • Won, Myoung-Soo;Koo, Kyo-Sang;Lee, Myung-Bo
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.8 no.4
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    • pp.250-259
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    • 2006
  • This study looks into forest fire occurrence hazards according to the change of temperature and humidity over thirty years at interval of ten days. We used data from the forest fire inventory from 1995 to 2004 and weather data such as average temperature and relative humidity for 30 years from 1971 to 2000. These data were expressed as a database with ten-day intervals for 76 weather stations. Forest fire hazards occurred in the spring season from the end of March to the middle of April. For the first step, the primitive surface of temperature and humidity was interpolated by IDW (the standard interpolation method). These thematic maps have a 1 km by 1 km grid spacing resolution. Next, we executed a simple regression analysis after extracting forest fire frequency, temperature and humidity values from 76 weather stations. The results produced a coefficient of determination ($R^2$) ranging from 0.4 to 0.6. Moreover, the estimation of forest fire occurrence hazards during early April was very high at Gyeongbuk Interior, Chungcheong Interior and part of Gangwon. The range of temperature and humidity having an influence on forest fire occurrence was as follows: average temperature and relative humidity in early April was $9-12^{\circ}C$ and 61-65%. At the end of March, temperature was $6-10^{\circ}C$, humidity 62-67%, and temperature was $11-14^{\circ}C$ and humidity 60-67% in the middle of April.

Storm-Based Dynamic Tag Cloud for Real-Time SNS Data (실시간 SNS 데이터를 위한 Storm 기반 동적 태그 클라우드)

  • Son, Siwoon;Kim, Dasol;Lee, Sujeong;Gil, Myeong-Seon;Moon, Yang-Sae
    • KIPS Transactions on Software and Data Engineering
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    • v.6 no.6
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    • pp.309-314
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    • 2017
  • In general, there are many difficulties in collecting, storing, and analyzing SNS (social network service) data, since those data have big data characteristics, which occurs very fast with the mixture form of structured and unstructured data. In this paper, we propose a new data visualization framework that works on Apache Storm, and it can be useful for real-time and dynamic analysis of SNS data. Apache Storm is a representative big data software platform that processes and analyzes real-time streaming data in the distributed environment. Using Storm, in this paper we collect and aggregate the real-time Twitter data and dynamically visualize the aggregated results through the tag cloud. In addition to Storm-based collection and aggregation functionalities, we also design and implement a Web interface that a user gives his/her interesting keywords and confirms the visualization result of tag cloud related to the given keywords. We finally empirically show that this study makes users be able to intuitively figure out the change of the interested subject on SNS data and the visualized results be applied to many other services such as thematic trend analysis, product recommendation, and customer needs identification.

West seacoast wetland monitoring using KOMPSAT series imageries in high spatial resolution (고해상도 KOMPSAT 시리즈 이미지를 활용한 서해연안 습지 변화 모니터링)

  • Sunwoo, Wooyeon;Kim, Daeun;Kim, Seongkyun;Choi, Minha
    • Journal of Korea Water Resources Association
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    • v.50 no.6
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    • pp.429-440
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    • 2017
  • A series of multispectral high-resolution Korean Multi-Purpose Satellite (KOMPSAT) images were analyzed to detect the geographical changes in four different tidal flats in the west coast of South Korea. The method of unsupervised classification was used to generate a series of land use/land cover (LULC) maps from the satellite images, which were used as the input of the temporal trajectory analysis to detect the temporal change of coastal wetlands and its association with natural and anthropogenic activities. The accurately classified LULC maps extracted from the KOMPSAT images indicate that these multispectral high-resolution satellite data is highly applicable to generate good quality thematic maps for extracting wetlands. The result of the trajectory analysis showed that, while the tidal flat area of Gyeonggi and Jeollabuk provinces was estimated to have changed due to tidal effects, the reductive trajectory of the wetland areas belonging to the Saemangeum province was caused by a high degree of human-induced activities including large reclamation and urbanization. The conservation of the Jeungdo Wetland Protected Area in Jeollanam province revealed that the social and environmental policies can effectively protect coastal wetlands from degradation. Therefore, monitoring for wetland change using high resolution KOMPSAT is expected to be useful to coastal environment management and policy making.

The Demand Survey and Correlational Analysis for Geological Data (지질 자료의 수요조사 및 상관성 분석)

  • Hwang, JaeHong;Chi, KwangHoon;Han, JongGyu;Yeon, YoungKwang;Ryu, Keun Ho
    • Journal of the Korean Association of Geographic Information Studies
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    • v.10 no.1
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    • pp.60-72
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    • 2007
  • In general, the importance of geological information is emphasized not only for national SOC construction, underground space development and energy resources development but also in areas related to environmental disasters such as mine damage, ground subsidence and landslides. Although geological information is highly useful in developing industrial raw materials, national land management and people's welfare, there is no unified governmental institution in charge of collecting and managing geological information in the national level. For this, this paper study: first, to analyze geological demand for common experts; second, to analyze geological demand for public institution; and third, to set priority for geological informatization. In the result of surveying demand for geological information, we need to improve laws and systems for collecting and reporting geology-related materials, making thematic maps, and maintaining and managing geological information we need to establish national strategies and build an integrated system for interoperability of databases and systems. Accordingly, we will guideline on future direction of strategies for the national integration of geological information management system.

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