• Title/Summary/Keyword: Geographic information systems analysis

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Accuracy Assessment of Reservoir Depth Measurement Data by Unmanned Boat using GIS (GIS를 이용한 무인보트의 저수지 수심측정자료 정확도 평가)

  • Kim, Dae-Sik
    • Journal of Korean Society of Rural Planning
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    • v.30 no.3
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    • pp.75-84
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    • 2024
  • This study developed the procedure and method for the accuracy assessment of unmanned boat survey data, based on the reservoir water depth data of Misan Reservoir, measured by the manned and unmanned boats in 2009 by Korea Rural Community Corporation. In the first step, this study devised the method to extract the contour map of NGIS data in AutoCAD to generate easily the reservoir boundary map used to set the survey range of reservoir water depth and to test the survey accuracy. The surveyed data coordinate systems of the manned and the unmanned boat were also unified by using ArcGIS for the standards of accuracy assessment. In the accuracy assessment, the spatial correlation coefficient of the grid maps of the two measurement results was 0.95, showing high pattern similarity, although the average error was high at 78cm. To analyze in more detail assessment, this study generated randomly the 3,250m transverse profile route (PR), and then extracted grid values of water depth on the PR. In the results of analysis to the extracted depth data on PR, the error average difference of the unmanned boat measurements was 73.18cm and the standard deviation of the error was 55cm compared to the manned boat. This study set these values as the standard for the correction value by average shift and noise removal of the unmanned boat measurement data. By correcting the unmanned boat measurements with these values, this study has high accuracy results, the reservoir water depth and surface area curve with R2 = 0.97 and the water depth and storage volume curve with R2 = 0.999.

The Analysis of Spatial Distribution of Gifted Education Units in Seoul (서울시 영재교육기관의 공간적 분포특성 분석)

  • Kim, Sungyeun;Lee, Seon-Young
    • Journal of Gifted/Talented Education
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    • v.25 no.5
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    • pp.711-729
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    • 2015
  • The purposes of this study are to derive the regions in Seoul that lack gifted education units by analyzing the spatial distribution of the units and to investigate the factors related to the unit locations. The gifted education units are divided into the three following types: the first type is a gifted class at a school, the second type is a gifted education center at a provincial office of education, and the third type is a gifted education center at a university. The results of using a GIS-based spatial analysis were as follows. First, a buffering analysis showed that even though there were gifted educational blind spots in Jongno-gu and in parts of the outskirts of Seoul, the spatial distribution of gifted education units in Seoul seemed homogeneous because they were too small. Second, a special quotient analysis showed that there was a hub unit of gifted education in Guro-gu. Third, an analysis of local Moran's Index showed that Jung-gu was a cold spot and Songa-gu was a hot spot. Fourth, a correlation analysis investigated that the number of gifted education units had generally no statistically significant relationship with economic factors. These results will help to improve the efficiency and equity of the management of the gifted education units in Seoul that will be established or expanded in the future.

Groundwater Systems in Seoul Area : Analysis of Hydraulic Properties (서울지역 지하수 시스템 조사 : 수리적 특성 분석)

  • 김윤영;이강근;성익환
    • The Journal of Engineering Geology
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    • v.8 no.1
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    • pp.51-73
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    • 1998
  • Hydrogeological systems in a metrnpolitan area can be understood by analyzing the groundwater disturbing factors such as constructions and land applications, the groundwater usage for domestic and industrial purposes, and the groundwater pumpage to lower the groundwater level for the structural safety of subway and underground facilities. This study is part of the study performed to understand the groundwater system in the Seoul area and it is focusing on the hydraulic properties. Groundwater well inventory, barometric efficiency measurements, pumping and slug tests, and long-term groundwater monitoring have been perfonrmed during the last 2 years. The relations between Han River and the groundwater around the river also have been observed. These observations and test data, together with the information on soil distribution, geology, and logging data are used to construct a database and GIS(Geographic Information System) presentation system using ARC/INFO. Barometric efficiencies appeared to have no special trends associated with well depths, which maeans that the degree of confinement of the crystaline rock aquifer of the Seoul area is distributed locally depending on the developrnent of fractures. Hydraulic conductivities exponentialiy decrease with well depth. The stage of Han River fluctuates according to the tidal movement of nearby seawater but the tidal effects attenuate due to the underwater dams. Groundwater levels in the Seoul area seem to have declined for the last two years,but it is not certain that the declination represents the long-term trend.

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An Analysis on the Usability of Unmanned Aerial Vehicle(UAV) Image to Identify Water Quality Characteristics in Agricultural Streams (농업지역 소하천의 수질 특성 파악을 위한 UAV 영상 활용 가능성 분석)

  • Kim, Seoung-Hyeon;Moon, Byung-Hyun;Song, Bong-Geun;Park, Kyung-Hun
    • Journal of the Korean Association of Geographic Information Studies
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    • v.22 no.3
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    • pp.10-20
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    • 2019
  • Irregular rainfall caused by climate change, in combination with non-point pollution, can cause water systems worldwide to suffer from frequent eutrophication and algal blooms. This type of water pollution is more common in agricultural prone to water system inflow of non-point pollution. Therefore, in this study, the correlation between Unmanned Aerial Vehicle(UAV) multi-spectral images and total phosphorus, total nitrogen, and chlorophyll-a with indirect association of algal blooms, was analyzed to identify the usability of UAV image to identify water quality characteristics in agricultural streams. The analysis the vegetation index Normalized Differences Index (NDVI), the Normalized Differences Red Edge(NDRE), and the Chlorophyll Index Red Edge(CIRE) for the detection of multi-spectral images and algal blooms collected from the target regions Yang cheon and Hamyang Wicheon. The analysis of the correlation between image values and water quality analysis values for the water sampling points, total phosphorus at a significance level of 0.05 was correlated with the CIRE(0.66), and chlorophyll-a showed correlation with Blue(-0.67), Green(-0.66), NDVI(0.75), NDRE (0.67), CIRE(0.74). Total nitrogen was correlated with the Red(-0.64), Red edge (-0.64) and Near-Infrared Ray(NIR)(-0.72) wavelength at the significance level of 0.05. The results of this study confirmed a significant correlations between multi-spectral images collected through UAV and the factors responsible for water pollution, In the case of the vegetation index used for the detection of algal bloom, the possibility of identification of not only chlorophyll-a but also total phosphorus was confirmed. This data will be used as a meaningful data for counterplan such as selecting non-point pollution apprehensive area in agricultural area.

A Study for Factors Influencing the Usage Increase and Decrease of Mobile Data Service: Based on The Two Factor Theory (모바일 데이터 서비스 사용량 증감에 영향을 미치는 요인들에 관한 연구: 이요인 이론(Two Factor Theory)을 바탕으로)

  • Lee, Sang-Hoon;Kim, Il-Kyung;Lee, Ho-Geun;Park, Hyun-Jee
    • Asia pacific journal of information systems
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    • v.17 no.2
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    • pp.97-122
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    • 2007
  • Conventional networking and telecommunications infrastructure characterized by wires, fixed location, and inflexibility is giving way to mobile technologies. Numerous research reports point to the ultimate domination of wireless communication. With the increasing prevalence of advanced cell-phones, various mobile data services (hereafter MDS) are gaining popularity. Although cellular networks were originally introduced for voice communications, statistics indicate that data services are replacing the matured voice service as the growth engine for telecom service providers. For example, SK Telecom, the Korea's largest mobile service provider, reported that 25.6% of revenue and 28.5% of profit came from MDS in 2006 and the share is growing. Statistics also indicate that, in 2006, the average revenue per user (ARPU) for voice didn't change but MDS grew seven percents from the previous year, further highlighting its growth potential. MDS is defined "as an assortment of digital data services that can be accessed using a mobile device over a wide geographic area." A variety of MDS have been deployed, with a few reaching the status of killer applications. Many of them need to access the Internet through the cellular-phone infrastructure. In the past, when the cellular network didn't have acceptable bandwidth for data services, SMS (short messaging service) dominated MDS. Now, Internet-ready, next-generation cell-phones are driving rich digital data services into the fabric of everyday life, These include news on various topics, Internet search, mapping and location-based information, mobile banking and gaming, downloading (i.e., screen savers), multimedia streaming, and various communication services (i.e., email, short messaging, messenger, and chaffing). The huge economic stake MDS has on its stakeholders warrants focused research to understand associated dynamics behind its adoption. Lyytinen and Yoo(2002) pointed out the limitation of traditional adoption models in explaining the rapid diffusion of innovations such as P2P or mobile services. Also, despite the increasing popularity of MDS, unexpected drop in its usage is observed among some people. Intrigued by these observations, an exploratory study was conducted to examine decision factors of MDS usage. Data analysis revealed that the increase and decrease of MDS use was influenced by different forces. The findings of the exploratory study triggered our confirmatory research effort to validate the uni-directionality of studied factors in affecting MDS usage. This differs from extant studies of IS/IT adoption that are largely grounded on the assumption of bi-directionality of explanatory variables in determining the level of dependent variables (i.e., user satisfaction, service usage). The research goal is, therefore, to examine if increase and decrease in the usage of MDS are explained by two separate groups of variables pertaining to information quality and system quality. For this, we investigate following research questions: (1) Does the information quality of MDS increase service usage?; (2) Does the system quality of MDS decrease service usage?; and (3) Does user motivation for subscribing MDS moderate the effect information and system quality have on service usage? The research questions and subsequent analysis are grounded on the two factor theory pioneered by Hertzberg et al(1959). To answer the research questions, in the first, an exploratory study based on 378 survey responses was conducted to learn about important decision factors of MDS usage. It revealed discrepancy between the influencing forces of usage increase and those of usage decrease. Based on the findings from the exploratory study and the two-factor theory, we postulated information quality as the motivator and system quality as the de-motivator (or hygiene) of MDS. Then, a confirmative study was undertaken on their respective role in encouraging and discouraging the usage of mobile data service.

CAPACITY EXPANSION MODELING OF WATER SUPPLY IN A PLANNING SUPPORT SYSTEM FOR URBAN GROWTH MANAGEMENT (도시성장관리를 위한 계획지원체계에서 상수도의 시설확장 모델링)

  • Hyong-Bok, Kim
    • Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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    • 1995.12a
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    • pp.9-21
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    • 1995
  • A planning support system enhances our ability to use water capacity expansion as an urban growth management strategy. This paper reports the development of capacity expansion modeling of water supply as part of the continuing development of such a planning support system (PEGASUS: Planning Environment for Generation and Analysis of Spatial Urban Systems) to incorporate water supply, This system is designed from the understanding that land use and development drive the demand for infrastructure and infrastructure can have a significant influence on the ways in which land is developed and used. Capacity expansion Problems of water supply can be solved in two ways: 1) optimal control theory, and 2) mixed integer nonlinear programming (MINLP). Each method has its strengths and weaknesses. In this study the MINLP approach is used because of its strength of determining expansion sizing and timing simultaneously. A dynamic network optimization model and a water-distribution network analysis model can address the dynamic interdependence between water planning and land use planning. While the water-distribution network analysis model evaluates the performance of generated networks over time, the dynamic optimization model chooses alternatives to meet expanding water needs. In addition, the user and capacity expansion modeling-to-generate-alternatives (MGA) can generate alternatives. A cost benefit analysis module using a normalization technique helps in choosing the most economical among those alternatives. GIS provide a tool for estimating the volume of demanded water and showing results of the capacity expansion model.

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An Study of Pedestrian Efficiency in Apartment Complexes - Focused on Pedestrian Path in Apartment Complexes - (아파트 단지의 보행효율성에 관한 연구 - 단지 내 보행로를 중심으로 -)

  • Yang, Dongwoo;Yu, Sang-Gyun
    • 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.

Genetic Variation and Polymorphism in Rainbow Trout, Oncorhynchus mykiss Analysed by Amplified Fragment Length Polymorphism

  • Yoon, Jong-Man;Yoo, Jae-Young;Park, Jae-Il
    • Journal of Aquaculture
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    • v.17 no.1
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    • pp.69-80
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    • 2004
  • The objective of the present study was to analyze genetic distances, variation and characteristics of individuals in rainbow trout, Oncorhynchus mykis using amplified fragment length polymorphism (AFLP) method as molecular genetic technique, to detect AFLP band patterns as genetic markers, and to compare the efficiency of agarosegel electrophoresis (AGE) and polyacrylamide gel electrophoresis (PAGE), respectively. Using 9 primer combinations, a total of 141 AFLP bands were produced, 108 bands (82.4%) of which were polymorphic in AGE. In PAGE, a total of 288 bands were detected, and 220 bands (76.4%) were polymorphic. The AFLP fingerprints of AGE were different from those of PAGE. Separation of the fragments with low molecular weight and genetic polymorphisms revealed a distinct pattern in the two gel systems. In the present study, the average bandsharing values of the individuals between two populations apart from the geographic sites in Kangwon-do ranged from 0.084 to 0.738 of AGE and PAGE. The bandsharing values between individuals No.9 and No. 10 showed the highest level within population, whereas the bandsharing values between individuals No.5 and No.7 showed the lowest level. As calculated by bandsharing analysis, an average of genetic difference (mean$\pm$SD) of individuals was approximately 0.590$\pm$0.125 in this population. In AGE, the single linkage dendrogram resulted from two primers (M11+H11 and M13+H11), indicating six genetic groupings composed of group 1 (No.9 and 10), group 2 (No. 1, 4, 5, 7, 10, 11, 16 and 17), group 3 (No. 2, 3, 6, 8, 12, 15 and 16), group 4 (No.9, 14 and 17), group 5 (No. 13, 19, 20 and 21) and group 6 (No. 23). In AGE, the genetic distances among individuals of between-population ranged from 0.108 to 0.392. In AGE, the shortest genetic distance (0.108) displaying significant molecular differences was between individuals No.9 and No. 10. Especially, the genetic distance between individuals No. 23 and the remnants among individuals within population was highest (0.392). Additionally, in the cluster analysis using the PAGE data, the single linkage dendrogram resulted from two primers (M12+H13 and M11+H13), indicating seven genetic groupings composed of group 1 (No. 15), group 2 (No. 14), group 3 (No. 11 and 12), group 4 (No.5, 6, 7, 8, 10 and 13), group 5 (No.1, 2, 3 and 4), group 6 (No.9) and group 7 (No. 16). By comparison with the individuals in PAGE, genetic distance between No. 10 and No. 7 showed the shortest value (0.071), also between No. 16 and No. 14 showed the highest value (0.242). As with the PAGE analysis, genetic differences were certainly apparent with 13 of 16 individuals showing greater than 80% AFLP-based similarity to their closest neighbor. The three individuals (No. 14, No. 15 and No. 16) of rainbow trout between two populations apart from the geographic sites in Kangwon-do formed distinct genetic distances as compared with other individuals. These results indicated that AFLP markers of this fish could be used as genetic information such as species identification, genetic relationship or analysis of genome structure, and selection aids for genetic improvement of economically important traits in fish species.

A Study on the Effective Method to Producing Data for The ROKA Live Fire Training Range Safety (한국군 실 사격 훈련간 효율적인 안전지대 데이터 구축 방안 연구)

  • Lee, June-Sik;Choi, Bong-Wan;Oh, Hyun-Seung
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.38 no.3
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    • pp.64-77
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    • 2015
  • An effective method for produce munitions effectiveness data is to calculate weapon effectiveness indices in the US military's Joint Munitions Effectiveness Manuals (JMEM) and take advantage of the damage evaluation model (GFSM) and weapon Effectiveness Evaluation Model (Matrix Evaluator). However, a study about the Range Safety that can be applied in the live firing exercises is very insufficient in the case of ROK military. The Range Safety program is an element of the US Army Safety Program, and is the program responsible for developing policies and guidance to ensure the safe operation of live-fire ranges. The methodology of Weapon Danger Zone (WDZ) program is based on a combination of weapon modeling/simulation data and actual impact data. Also, each WDZ incorporates a probability distribution function which provides the information necessary to perform a quantitative risk assessment to evaluate the relative risk of an identified profile. A study of method to establish for K-Range Safety data is to develop manuals (pamphlet) will be a standard to ensure the effective and safe fire training at the ROK military education and training and environmental conditions. For example, WDZs are generated with the WDZ tool as part of the RMTK (Range Managers Tool Kit) package. The WDZ tool is a Geographic Information System-based application that is available to operational planners and range safety manager of Army and Marine Corps in both desktop and web-based versions. K-Range Safety Program based on US data is reflected in the Korean terrain by operating environments and training doctrine etc, and the range safety data are made. Thus, verification process on modified variables data is required. K-Range Safety rather than being produced by a single program, is an package safety activities and measures through weapon danger zone tool, SRP (The Sustainable Range Program), manuals, doctrine, terrain, climate, military defence M&S, weapon system development/operational test evaluation and analysis to continuously improving range safety zone. Distribution of this K-range safety pamphlet is available to Army users in electronic media only and is intended for the standing army and army reserve. Also publication and distribution to authorized users for marine corps commands are indicated in the table of allowances for publications. Therefore, this study proposes an efficient K-Range Safety Manual producing to calculate the danger zones that can be applied to the ROK military's live fire training by introducing of US Army weapons danger zone program and Range Safety Manual

Development of Mask-RCNN Model for Detecting Greenhouses Based on Satellite Image (위성이미지 기반 시설하우스 판별 Mask-RCNN 모델 개발)

  • Kim, Yun Seok;Heo, Seong;Yoon, Seong Uk;Ahn, Jinhyun;Choi, Inchan;Chang, Sungyul;Lee, Seung-Jae;Chung, Yong Suk
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.23 no.3
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    • pp.156-162
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    • 2021
  • The number of smart farms has increased to save labor in agricultural production as the subsidy become available from central and local governments. The number of illegal greenhouses has also increased, which causes serious issues for the local governments. In the present study, we developed Mask-RCNN model to detect greenhouses based on satellite images. Greenhouses in the satellite images were labeled for training and validation of the model. The Mask-RC NN model had the average precision (AP) of 75.6%. The average precision values for 50% and 75% of overlapping area were 91.1% and 81.8%, respectively. This results indicated that the Mask-RC NN model would be useful to detect the greenhouses recently built without proper permission using a periodical screening procedure based on satellite images. Furthermore, the model can be connected with GIS to establish unified management system for greenhouses. It can also be applied to the statistical analysis of the number and total area of greenhouses.