• Title/Summary/Keyword: Spatial Distance

Search Result 1,393, Processing Time 0.025 seconds

A Study on the Improvement of Satellite Image Information Service System (위성영상정보 서비스 시스템 개선방안 연구)

  • Cho, Bo-Hyun;Yang, Keum-Cheol;Kim, Song-Gang;Yoo, Seung-Jae
    • Convergence Security Journal
    • /
    • v.17 no.5
    • /
    • pp.41-47
    • /
    • 2017
  • The Marine Environment Observation Information System supplies oceanographic information elements such as water temperature, chlorophyll, float, etc. based on satellite images to consumers. The data produced by the Korean marine environmental observatories are located in the coastal areas of Korea. But if the range is too far from a particular area of interest, due to distance or spatial constraints, the accuracy and up-to-dateness of the data can not be relied upon. Therefore, it is necessary to perform fusion and complex operation to solve the difference between the field observation and the marine satellite image. In this study, we develop a system that can process marine environmental information in the user's area of interest in the form of layered character (numeric) information considering the readability and light weight rather than the satellite image. In order to intuitively understand satellite image information, we characterize (quantify) the marine environmental information of the area of interest and we process the satellite image band values into layered characters to minimize the absolute amount of transmitted / received data. Also we study modular location-based interest information service method to be able to flexibly extend and connect interested items that diversify various observation fields as well as application technology to serve this.

Influence of (E)-2-hexenyl (Z)-3hexenoate on the Occurrence of Egg Parasitoids, Ooencyrtus nezarae (Hymenoptera: Encyrtidae) and Gryon japonicum (Hymenoptera: Scelionidae), in Apple Orchards (사과원에서 (E)-2-hexenyl (Z)-3hexenoate 성분이 노린재깡충좀벌(Ooencyrtus nezarae)(Hymenoptera: Encyrtidae)과 노린재기생알벌(Gryon japonicum) (Hymenoptera: Scelionidae) 발생에 미치는 영향)

  • Baek, Seonghoon;Park, Chung Gyoo;Seo, Bo Yoon;Cho, Jum Rae;Park, Chang-Gyu
    • Korean journal of applied entomology
    • /
    • v.60 no.1
    • /
    • pp.91-98
    • /
    • 2021
  • The populations of Riptortus pedestris (Fabricius) cause serious economic damages in local apple orchards. However, there was no study to manage its populations with environment friendly tactics. Thus, this study was conducted to analyze its attraction effects of one of R. pedestris aggregation pheromone compounds, (E)-2-hexenyl (Z)-3hexenoate (E2HZ3H), to its parasitoids, Ooencyrtus nezarae (Ishii) and Gryon japonicum (Ashmead). This compound did not increase the number of these two parasitoids and change its spatial distribution. However, this compound could attract two parasitoids within limited distance. These results indicates that one compound of R. pedestris aggregation pheromone, E2HZ3H, could be a good candidate to manage R. pedestris populations in conditions that its populations locally occurs in apple orchards.

Analysis of Effect of Infrastructure Property on an Apartment Housing Price - Focused on Urban Subway System in Seoul Metropolitan Area - (사회기반시설 이용특성에 따른 공동주택의 가격 영향에 관한 연구 - 수도권 도시철도를 중심으로 -)

  • Bae, Sangyoung;Lee, Sangyoub
    • Korean Journal of Construction Engineering and Management
    • /
    • v.22 no.1
    • /
    • pp.27-35
    • /
    • 2021
  • The study intends to identify the effects of infrastructure property on an apartment house by analyzing the price variation affected by factors constituting the quality of the transit services of each individual station in urban railway system based on hedonic price model. The research findings indicate that the prices depending on the transit users have increased from 7.8% to 12.2% in Seoul and decreased from 6.1% to 12.9% in Gyeonggi, which implies that a lower number of transfer users has a positive effect on housing prices in Seoul unlike Gyeonggi. It also is noteworthy that the distance to the urban railway station had a negative effect on housing prices in Seoul and positive effect in Gyeonggi. Taking these results together, in Seoul, the increase in the number of transit users had a negative effect on neighborhood housing prices. When analyzed by segments, however, an additional negative effect was observed only in the apartments located within the radius of 100 meters. It is also found that the impact of transit users varies according to the regional characteristics, such as the density of commercial facilities and the population density, and the spatial extent of negative effect also showed regional differences. These results provide implications for the planning of new stations, new cities, and land use of existing areas around stations.

Development of Surface Velocity Measurement Technique without Reference Points Using UAV Image (드론 정사영상을 이용한 무참조점 표면유속 산정 기법 개발)

  • Lee, Jun Hyeong;Yoon, Byung Man;Kim, Seo Jun
    • Ecology and Resilient Infrastructure
    • /
    • v.8 no.1
    • /
    • pp.22-31
    • /
    • 2021
  • Surface image velocimetry (SIV) is a noncontact velocimetry technique based on images. Recently, studies have been conducted on surface velocity measurements using drones to measure a wide range of velocities and discharges. However, when measuring the surface velocity using a drone, reference points must be included in the image for image correction and the calculation of the ground sample distance, which limits the flight altitude and shooting area of the drone. A technique for calculating the surface velocity that does not require reference points must be developed to maximize spatial freedom, which is the advantage of velocity measurements using drone images. In this study, a technique for calculating the surface velocity that uses only the drone position and the specifications of the drone-mounted camera, without reference points, was developed. To verify the developed surface velocity calculation technique, surface velocities were calculated at the Andong River Experiment Center and then measured with a FlowTracker. The surface velocities measured by conventional SIV using reference points and those calculated by the developed SIV method without reference points were compared. The results confirmed an average difference of approximately 4.70% from the velocity obtained by the conventional SIV and approximately 4.60% from the velocity measured by FlowTracker. The proposed technique can accurately measure the surface velocity using a drone regardless of the flight altitude, shooting area, and analysis area.

Evaluation Research on the Protection and Regeneration of the Urban Historical and Cultural District of Pingjiang Road, Suzhou, China (중국 쑤저우 평강로 도시역사문화거리 보존 및 재생사업 평가연구)

  • Geng, Li;Yoon, Ji-Young
    • The Journal of the Korea Contents Association
    • /
    • v.21 no.5
    • /
    • pp.561-580
    • /
    • 2021
  • This study analyses the historical and cultural streets at Pinggang Road in the city of Suzhou, by understanding the development and conservation of the area, and uses the following ways to investigate its development, re-organization, and current state. This paper comprehensively compares, collates and investigates 4 different historical and cultural areas in Insadong and Samcheong-dong in South Korea, and South Luogu Lane in China. From initial research and analysis, this paper gathers the cultural, economic, and societal perspectives as non-physical measures, and spatial structure, road structure, and building maintenance as physical factor framework. It is significant in that it can provide an evaluation model for the preservation and regeneration of historical and cultural streets by presenting the viewpoint of complex development of non-physical and physical elements in Pyeonggang-ro. In addition, it is necessary to conduct optimization and specific research on insufficient areas, such as maintenance and development of programs and signature systems for visitors, and continuous development of historical and cultural network platforms by combining on-site surveys. Basic data should be provided for reference on the street.

A Study on the Formation and Landscape Characteristics of Imperial Tombs Created in the Qing Dynasty, China (중국 청대(淸代) 황가능침원(皇家陵寢園)의 조형 및 경관적 특성)

  • RHO, Jaehyun;WEI, Hang
    • Korean Journal of Heritage: History & Science
    • /
    • v.55 no.1
    • /
    • pp.5-34
    • /
    • 2022
  • The purpose of this study is to investigate the unique contrasting landscape characteristics of imperial tombs of Qing dynasty by examining the characteristics of facility layout in which location, Feng shui, and siblings are harmonized with the 12 Qing Dynasty Hwanggyeongchim. Through literature surveys, field observation and interviews, videos and drawing comparison, and inductive contrast analysis, the contrasting landscape characteristics of imperial tombs in the Qing Dynasty were analyzed by classifying them into natural environment, location, Feng shui, and formal esthetics. As a result, the characteristics of the location type and the layout plan of the Qing dynasty imperial tombs were derived from the analysis of Feng shui shape, axis extension distance along the midaxial line, the width of the ridge, the formality of the facility layout according to the difference between the height of the starting point and the end point, the leftward direction of the tomb, and the space ratio of the 'entry space' - 'ritual space' - 'burial mound space', etc. In addition, it was possible to derive the facility arrangement characteristics of tombstones through the analysis of the types and the arrangement order of tombs facilities, as well as the distribution, quantity and types of stone figures, while also revealing some contrasting characteristics different from those of the Ming Dynasty. In addition, it was confirmed that the spatial division effect through the water system and the view effect of the view from the midaxial line and the vista are the representative view effect found in the Qing Dynasty imperial tombs along with the density contrast.

Providing the combined models for groundwater changes using common indicators in GIS (GIS 공통 지표를 활용한 지하수 변화 통합 모델 제공)

  • Samaneh, Hamta;Seo, You Seok
    • Journal of Korea Water Resources Association
    • /
    • v.55 no.3
    • /
    • pp.245-255
    • /
    • 2022
  • Evaluating the qualitative the qualitative process of water resources by using various indicators, as one of the most prevalent methods for optimal managing of water bodies, is necessary for having one regular plan for protection of water quality. In this study, zoning maps were developed on a yearly basis by collecting and reviewing the process, validating, and performing statistical tests on qualitative parameters҆ data of the Iranian aquifers from 1995 to 2020 using Geographic Information System (GIS), and based on Inverse Distance Weighting (IDW), Radial Basic Function (RBF), and Global Polynomial Interpolation (GPI) methods and Kriging and Co-Kriging techniques in three types including simple, ordinary, and universal. Then, minimum uncertainty and zoning error in addition to proximity for ASE and RMSE amount, was selected as the optimum model. Afterwards, the selected model was zoned by using Scholar and Wilcox. General evaluation of groundwater situation of Iran, revealed that 59.70 and 39.86% of the resources are classified into the class of unsuitable for agricultural and drinking purposes, respectively indicating the crisis of groundwater quality in Iran. Finally, for validating the extracted results, spatial changes in water quality were evaluated using the Groundwater Quality Index (GWQI), indicating high sensitivity of aquifers to small quantitative changes in water level in addition to severe shortage of groundwater reserves in Iran.

Major environmental factors and traits of invasive alien plants determining their spatial distribution

  • Oh, Minwoo;Heo, Yoonjeong;Lee, Eun Ju;Lee, Hyohyemi
    • Journal of Ecology and Environment
    • /
    • v.45 no.4
    • /
    • pp.277-286
    • /
    • 2021
  • Background: As trade increases, the influx of various alien species and their spread to new regions are prevalent and no longer a special problem. Anthropogenic activities and climate changes have made the distribution of alien species out of their native range common. As a result, alien species can be easily found anywhere, and they have nothing but only a few differences in intensity. The prevalent distribution of alien species adversely affects the ecosystem, and a strategic management plan must be established to control them effectively. To this end, hot spots and cold spots were analyzed according to the degree of distribution of invasive alien plants, and major environmental factors related to hot spots were found. We analyzed the 10,287 distribution points of 126 species of alien plants collected through the national survey of alien species by the hierarchical model of species communities (HMSC) framework. Results: The explanatory and fourfold cross-validation predictive power of the model were 0.91 and 0.75 as AUC values, respectively. The hot spots of invasive plants were found in the Seoul metropolitan area, Daegu metropolitan city, Chungcheongbuk-do Province, southwest shore, and Jeju island. Generally, the hot spots were found where the higher maximum temperature of summer, precipitation of winter, and road density are observed, but temperature seasonality, annual temperature range, precipitation of the summer, and distance to river and sea were negatively related to the hot spots. According to the model, the functional traits accounted for 55% of the variance explained by the environmental factors. The species with higher specific leaf areas were more found where temperature seasonality was low. Taller species preferred the bigger annual temperature range. The heavier seed mass was only preferred when the max temperature of summer exceeded 29 ℃. Conclusions: In this study, hot spots were places where 2.1 times more alien plants were distributed on average than non-hot spots (33.5 vs 15.7 species). The hot spots of invasive plants were expected to appear in less stressful climate conditions, such as low fluctuation of temperature and precipitation. Also, the disturbance by anthropogenic factors or water flow had positive influences on the hot spots. These results were consistent with the previous reports about the ruderal or competitive strategies of invasive plants instead of the stress-tolerant strategy. The functional traits are closely related to the ecological strategies of plants by shaping the response of species to various environmental filters, and our result confirmed this. Therefore, in order to effectively control alien plants, it is judged that the occurrence of disturbed sites in which alien plants can grow in large quantities is minimized, and the river management of waterfronts is required.

A Study on the Method of Evaluating Optical-system Performance and an Athermal Structure through Thermal Analysis of the Korsch Telescope (Korsch 망원경의 열분석을 통한 광학계 성능 평가 방법 및 비열화 구조 연구)

  • Kim, Kyu-Ho;Park, Seong-Woo;Park, Seung-Han;Lee, Kyoung-Mook;Jung, Mee-Suk
    • Korean Journal of Optics and Photonics
    • /
    • v.32 no.6
    • /
    • pp.266-275
    • /
    • 2021
  • In this paper, a method for evaluating optical-system performance and an athermal structure through thermal analysis of the Korsch telescope was studied. In the case of an optical system having a complex asymmetrical structure, there is a limit to implementing the satellite structure by applying the coefficient of thermal expansion (CTE) in the optical-design software, so it is difficult to evaluate the performance of the optical system against temperature changes. To solve this problem, using mechanical design software all length changes were implemented in all structures that affect the optical system according to temperature, and the value of the change in distance between optical components due to temperature change was organized. Also, the values of changes in shape and thickness of the optical components against temperature changes are organized in the optical-design software. All changes derived from both software packages were applied in the optical software to evaluate the performance of the optical system. As a result, it was found that the MTF for a spatial resolution of 71.4 cycles/mm was maintained at more than 25% in the range from 9 ℃ to 33 ℃. In addition, the performance of the optical system applying the improved structure was evaluated, by finding the structure that had the most influence on the optical system's performance change, and deriving an athermal structure to reduce the effect. As a result, it was found that the MTF for a resolution of 71.4 cycles/mm was maintained at over 67% in the range from 9 ℃ to 33 ℃.

A Study on the Relevancy of Application of Land Suitability Assessment in Developed Urban Areas: the case of Seoul (도시지역 토지적성평가의 적정성에 관한 연구 - 서울시를 중심으로 -)

  • Lee, Sekwang;Park, joon
    • Journal of the Korean Regional Science Association
    • /
    • v.38 no.2
    • /
    • pp.43-57
    • /
    • 2022
  • The Land Suitability Assessment is mandatory by National Land Planning and Utilization Act and the results are considered in the establishment of urban master plan and urban management plan. The study aims to examine whether the application of Land Suitability Assessment in developed urban areas is appropriate. A simulation analysis based on the Seoul's data of environmental ecological, physical, and spatial characteristics was conducted on urban green, the only applicable land for the assessment in Seoul. The results of the assessment shows that all pieces of lands in urban green is suitable for 'development'. This conflicts to the purpose of land use of urban green which needs to be conserved to protect the natural environment and landscape, animals and plants, environmental pollution, and urban sprawl. In the analysis applying optional indicators such as the distance from the area of Biotope Class 1 to prevent this conflict, the results shows little difference. This supports the necessity to review this regulation including an option to exclude developed urban areas such as Seoul in the assessment.