• Title/Summary/Keyword: time-space distribution

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A Study on the Movement of Street-based Urban Morphology Using Analysis of Integrated Land Use-Transportation (토지이용-교통 통합적 분석을 통한 도로 기반 도시 형태학적 변화에 관한 연구)

  • Joo, Yong-Jin
    • Spatial Information Research
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    • v.19 no.3
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    • pp.63-72
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    • 2011
  • Urban space structure tends to have a significant change in accordance with maintenance of urban infrastructure such as a traffic route. For this reason, quantitative analysis has been needed to establish spatial distribution and location patterns by considering change of both road accessibility and urban infrastructure level, which can have the most pervasive influence in urban development process. Therefore, this paper aims to analyze spatio-temporal urban morphology through considering distribution patterns of road among transportation infrastructures, population, and spatial structure of metropolitan areas, focusing on Seoul where population growth and the size of urban area have been dramatically increased. For this, we firstly developed and constructed time-series GIS database by using satellite images and topographic maps of the last 70 years to analyze variables which affect urban growth and transportation. In particular, we analyzed the transform of the system of the street by Space Syntax which is able to grasp hierarchical spatial structure through visibility of space and spatial cognition in terms of accessibility. What's more, we analyzed and visualized the relationship urban morphology and road according the regions of Seoul through IPA(Importance Performance Analysis). In terms of the integration land-use and transportation, Space Syntax approach is expected to contribute to efficient urban planning through understanding the influence which various transportation phenomena has an effect on urban development patterns.

Spatial-temporal distribution of carabid beetles in wetlands

  • Do, Yu-No;Jo, Hyun-Bin;Kang, Ji-Hoon;Joo, Gea-Jae
    • Journal of Ecology and Environment
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    • v.35 no.1
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    • pp.51-58
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    • 2012
  • In this study, we investigated carabid beetles residing in the wetlands to understand their ecological adaptation and strategy selection associated with restricted resources and habitat limitation. The species richness, abundance, seasonal activity, and spatial distribution of the carabid beetles between the Mujechi Wetlands (wetland sites) and Mt. Jeongjok (mountain sites) have been compared. A total of 1,733 individual beetles from 30 species were collected and classified at the studied sites. The wetland sites were identified as having lower species richness and abundance for carabid beetles when compared with the adjacent mountain sites, whereas these beetles were observed to be dominant in the wetland sites than in the adjacent mountain sites. Calosoma inquisitor cyanescens, Carabus sternbergi sternbergi, and Carabus jankowskii jankowskii species were dominant in both the wetland and mountain sites. These species showed significantly different seasonal activity patterns in the wetland sites relative to the mountain sites. Although the three listed carabid species were observed to be widely distributed throughout the wetland sites, they still showed preference for drier sites, which clearly shows a distinction in their habitats. The results of the spatial-temporal distribution of carabid beetles in the wetland sites reflect their special strategies regarding space and time partitioning for maintaining their population. The distribution patterns of carabid beetles in the wetland sites also showed the desiccation gradient and environmental changes prevalent in wetlands. Ecological surveys, which use carabid beetles in the wetlands, can then be performed when restoring wetlands and for establishing management practices for improving the habitat quality.

The Temporal and Spatial Distribution Analysis of Red Tide using GIS (GIS를 이용한 적조의 시-공간적 분포 분석)

  • Jeong Jong-chul
    • Spatial Information Research
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    • v.13 no.3 s.34
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    • pp.253-260
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    • 2005
  • The aim of this study is to analyze the temporal and spatial distribution aspects of red tide using GIS techniques. The damage caused by red tide appears various aspects according to the species, concentration and spatial distribution of red tide plankton. Therefore, in order to prevent the damage of red tide it is important to understand the distribution characteristics of red tide by each species according to time and space. In this perspective, we analyzed the beginning outbreak area, spatial occurrence frequency and spatial migration of red tide. The spatial data used by this study was constructed by digitizing the red tide quick report and coupled with various attributes such as species, concentration and water temperature for construction of red tide database. We used various spatial analysis methods such as union, intersect, tracking, buffer and spatial interpolation for analyzing temporal and spatial characteristics of red tide. From the result of these spatial analyses, we could get the spatial information on the temporal and spatial distribution characteristics of red tide at the Southern Sea.

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Investigation of the body distribution of load pressure and virtual wear design of short pants harnesses in flying condition (플라잉 상태에서 바지형태의 하네스에 대한 하중압력 분포 측정 및 가상착의 적용)

  • Kwon, MiYeon
    • Journal of the Korea Fashion and Costume Design Association
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    • v.23 no.3
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    • pp.11-21
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    • 2021
  • Virtual reality is currently mainly used in games, but is starting to be applied as a variety of media fields, such as broadcasting and film. Virtual reality provides more fun than reality, and can provide new experiences in areas that cannot be experienced in reality due to the constraints of time, space, and environment. In particular, as the social non-contact arena has increased due to COVID-19, it is being applied to education, health, and medical industries. The contents are further expanding into design and military fields. Therefore, the purpose of this study was to observe the change in distribution of load and pressure felt by the body in the flying state while wearing a short pants harness, which are mainly used in the game and entertainment industry. In the experiment, the average pressure in the flying state was measured by attaching a pressure sensor to the back and front of a human mannequin. As a result, it was confirmed that the load concentrated on the waist in the flying state was 44 N, with a pressure of 1353 kPa. The pressure distribution was concentrated in front of the center of gravity, and was measured was at 98% by the pressure sensors, with an average pressure value of approximately 15 kPa, and a pressure value of approximately 12 kPa at the back, which was measured at 67% by the pressure sensor. The results of the load and pressure distribution measurement are presented as fundamental data to improve the wearability and comfort of harnesses in the future, and are compared to actual measured pressure values by analyzing the clothing pressure in flight through virtual wear of harnesses through the CLO 3D program.

Simulation of Solar Irradiance Distribution Under Agrivoltaic Facilities (영농형 태양광 발전 시설 하부의 일사량 분포 모의)

  • Jeong, Young-Joon;Lee, Sang-Ik;Lee, Jong-Hyuk;Seo, Byung-Hun;Kim, Dong-Su;Lee, Jimin;Choi, Won
    • Journal of The Korean Society of Agricultural Engineers
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    • v.64 no.2
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    • pp.1-13
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    • 2022
  • Agrivoltaic facility is the composite system that the solar panel is installed above the farmland, and it enables crop and electricity production simultaneously. Solar panels of the agrivoltaic facilities can block and reduce the amount of solar irradiance arriving at the farmland, but it can help the crop growth by preventing excessive solar irradiance. Therefore, to clarify how the agrivoltaic facilities affect the crop growth, precise solar irradiance distribution under the solar panel should be modeled. In this study, PAR (photosynthetically active radiation), radiation from 400 to 700 nm, which crops usually use to grow, was extracted from the total irradiance and its distribution model under various conditions was developed. Monthly irradiance distributions varied because the elevation of the sun was changed over time, which made the position changed that the local maximum and minimum irradiance appear. The higher panel height did not cause any significant difference in the amount of irradiance reaching below the solar panel, but its distribution became more uniform. Furthermore, the panel angles with the most irradiance arriving below the solar panel were different by month, but its difference was up to 2%p between the irradiance with 30° angle which is usually recommended in Korea. Finally, the interval between panels was adjusted; when the ratio of the length of the panel to the empty space was 1:2, the irradiance of 0.719 times was reached compared to when there was no panel, 0.579 times for 1:1 and 0.442 times for 2:1.

Hyper-Rectangle Based Prototype Selection Algorithm Preserving Class Regions (클래스 영역을 보존하는 초월 사각형에 의한 프로토타입 선택 알고리즘)

  • Baek, Byunghyun;Euh, Seongyul;Hwang, Doosung
    • KIPS Transactions on Software and Data Engineering
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    • v.9 no.3
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    • pp.83-90
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    • 2020
  • Prototype selection offers the advantage of ensuring low learning time and storage space by selecting the minimum data representative of in-class partitions from the training data. This paper designs a new training data generation method using hyper-rectangles that can be applied to general classification algorithms. Hyper-rectangular regions do not contain different class data and divide the same class space. The median value of the data within a hyper-rectangle is selected as a prototype to form new training data, and the size of the hyper-rectangle is adjusted to reflect the data distribution in the class area. A set cover optimization algorithm is proposed to select the minimum prototype set that represents the whole training data. The proposed method reduces the time complexity that requires the polynomial time of the set cover optimization algorithm by using the greedy algorithm and the distance equation without multiplication. In experimented comparison with hyper-sphere prototype selections, the proposed method is superior in terms of prototype rate and generalization performance.

Identifying High-Risk Clusters of Gastric Cancer Incidence in Iran, 2004 - 2009

  • Kavousi, Amir;Bashiri, Yousef;Mehrabi, Yadollah;Etemad, Korosh;Teymourpour, Amir
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.23
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    • pp.10335-10337
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    • 2015
  • Background: Gastric cancer is considered as the second most prevalent cancer in Iran. The present research sought to identify high risk clusters of gastric cancer with mapping using space-time scan statistics. Materials and Methods: The present research is of descriptive type. The required data were gathered from the registered cancer reports of Cancer Control Office in the Center for Non Communicable Disease of the Ministry of Health (MOH). The data were extracted at province level in the time span of 2004-9. Sat-Scan software was used to analyse the data and to identify high risk clusters. ArcGIS10 was utilized to map the distribution of gastric cancer and to demonstrate high risk clusters. Results: The most likely clusters were found in Ardabil, Gilan, Zanjan, East-Azerbaijan, Qazvin, West-Azerbaijan, Kurdistan, Hamadan, Tehran and Mazandaran between 2007 and 2009. It was statistically significant at the p-value below 0.05. Conclusions: High risk regions included Northern, West-North and central provinces, particularly Ardabil, Kurdistan, Mazandaran and Gilan. More screening tests are suggested to be conducted in high risk regions along with more frequent epidemiological studies to enact gastric cancer prevention programs.

A Study on Optimum Takeoff Time of the Hybrid Electric Powered Systems for a Middle Size UAV (중형무인기용 하이브리드 전기동력시스템의 최적 이륙시간에 관한 연구)

  • Lee, Bohwa;Park, Poomin;Kim, Keunbae;Cha, Bongjun
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.40 no.11
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    • pp.940-947
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    • 2012
  • The target system is a middle size UAV, which is a low-speed long-endurance UAV with a weight of 18 kg and wingspan of 6.4 m. Three electric power sources, i.e. solar cells, a fuel cell, and a battery, are considered. The optimal takeoff time is determined to maximize the endurance because the generated solar cell's energy is heavily dependent on it. Each power source is modeled in Matlab/Simulink, and the component models are verified with the component test data. The component models are integrated into a power system which is used for power simulations. When takeoff time is at 6 pm and 2 am, it can supply the power during 37.5 hrs and 27.6 hrs, respectively. In addition, the thermostat control simulation for fuel cell demonstrates that it yields more power supply and efficient power distribution.

CHARACTERISTICS OF THE FAIRCHILD 486 CCD AT MAIDANAK ASTRONOMICAL OBSERVATORY IN UZBEKISTAN (우즈베키스탄 Maidanak 천문대 Fairchild 486 CCD의 기본적인 특성)

  • Lim, Beom-Du;Sung, Hwan-Kyung;Karimov, R.;Ibrahimov, M.
    • Publications of The Korean Astronomical Society
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    • v.23 no.1
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    • pp.1-12
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    • 2008
  • Understanding of the basic characteristics of an astronomical instrument is a prerequisite to obtaining reliable data from the instrument. We have analyzed more than 1,000 calibration images from the Fairchild 486 CCD (hereafter the Maidanak 4k CCD system) attached to the AZT-22 1.5m telescope at Maidanak Astronomical Observatory in Uzbekistan. The Maidanak 4k CCD system supports three readout modes through 1, 2, or 4 amplifiers. In most cases observers use 4-amplifier readout mode to save time. We have tested the stability and seasonal variation of zero levels and confirm that two quadrants of the images (Amp 1 & 2) show no appreciable seasonal variation. but the other two quadrants (Amp 3 & Amp 4) show an evident seasonal variation in the bias level. The Cryo Tiger, the cooling system used at the Maidanak 4k CCD system, maintains the CCD temperature at -108'E, and effectively suppresses the dark electrons. The mean value versus the variance plot of the flat images does not show the expected relation for an ideal Poisson noise distribution and this is attributed to the large variation in quantum efficiency between different pixels. In addition, we confirm that there is no appreciable difference in gain between readout amplifiers, but there is a large variation in quantum efficiency across CCD chip especially in U. Due to the finite length of shutter opening and closing time, the effective exposure time varies across the science images. We introduce two parameters to quantify the effect of this uneven illumination and present a method to remove these effects. We also present a method to remove the interference patterns appearing in the images obtained with longer wavelength filters and investigate the spatial variation of the point spread function.

Development of Vehicle Emission Model with a High Resolution in Time and Space (${\cdot}$공간적 고해상도 자동차 배출량 모형의 개발)

  • Park, Seong-Kyu;Kim, Shin-Do;Park, Ki-Hark
    • Journal of Environmental Health Sciences
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    • v.30 no.3
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    • pp.293-299
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    • 2004
  • Traffic represents one of the largest sources of primary air pollutants in urban area. As a consequence, numerous abatement strategies are being pursued to decrease the ambient concentration of pollutants. A characteristics of most of the these strategies is a requirement for accurate data on both the quantity and spatial distribution of emissions to air in the form of an atmospheric emission inventory database. In the case of traffic pollution, such an inventory must be compiled using activity statistics and emission factors for vehicle types. The majority of inventories are compiled using passive data from either surveys or transportation models and by their very nature tend to be out-of-date by the time they are compiled. The study of current trends is towards integrating urban traffic control systems and assessments of the environmental effects of motor vehicles. In this study, a model of vehicle emission calculation by using real-time traffic data was studied. Traffic data, which are required on a street-by-street basis, is obtained from induction loops of traffic control system. It is possible that characteristics of hourly air pollutants emission rates is obtained from hourly traffic volume and speed. An emission rates model is allocated with a high resolution space by using geographic information system (GIS). Vehicle emission model was developed with a high resolution spatial, gridded and hourly emission rates.