• Title/Summary/Keyword: data sources

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Numerical Simulation of Environmental Pollutants at Yosu, Korea and Comparison with Measured Data

  • Lee, S. D.;A. Kondo;K. Yoshimura;K. Yamaguchi;A. Kaga
    • Journal of Korean Society for Atmospheric Environment
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    • v.19 no.E2
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    • pp.63-73
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    • 2003
  • The atmospheric pollution distribution in the industrial area of Yosu in Korea is calculated using numerical model and the model is validated by comparing the calculations with observed data. The emission of NO$_{x}$ and SO$_{x}$ was estimated for 6 sources, and the emission amount of HC was estimated for 9 anthropogenic sources. The calculated wind speed, wind direction and temperature agreed well with the observed data at two observatories, and the calculated concentration of NO, NO$_2$, $O_3$ and SO$_2$ were also reasonable for 5 monitoring stations. The validity of the model is evaluated using 3 indexes of the EPA, and the model is found to be valid and accurate.ate.

Sources of Income Polarization in Korea: Globalization and Technological Innovation

  • Shin, Taeyoung
    • STI Policy Review
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    • v.7 no.2
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    • pp.1-15
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    • 2016
  • This study provides empirical evidences for the relationship between income inequality and economic growth, and relationship of income inequality with some of explanatory variables such as technological innovation, trade globalization, financial globalization and fiscal policy. We find out that income inequality has an adverse effect on economic growth, showing its dynamic features, for which we employed the polynomial distributed lags (PDL) model. The effect of income inequality on economic growth lasts over 9 years, and its dynamic effect peaks after 4 years. In addition, we also attempted to find out empirical evidences of sources of income inequality. The results show that income inequality is positively related to technological innovation, financial globalization, and fiscal policy; negatively related to the trade globalization. Many studies employ cross-country data, but it could have serious problems in collecting statistical data. Korean data is used over the time period of 1990-2015 in this study.

Near-IR Polarimetry Survey of the Large Magellanic Cloud: Relationship between the polarization degree and the color

  • Kim, Jaeyeong;Pak, Soojong;Kang, Wonseok;Choi, Minho
    • The Bulletin of The Korean Astronomical Society
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    • v.37 no.2
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    • pp.100.2-100.2
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    • 2012
  • We performed near-IR imaging polarimetry of the $5{\times}9$ fields (${\sim}39^{\prime}{\times}69^{\prime}$) around 30 Doradus in the Large Magellanic Cloud (LMC), using the InfraRed Survey Facility (IRSF). We obtained polarimetry data in the J, H, and Ks bands using the JHKs-simultaneous imaging polarimeter SIRPOL in 2008 December and 2011 December. With the reliable LMC field data which were selected using a bad-data-rejection algorithm, we measured Stokes parameters of point-like sources to derive the degree of polarization and the polarization position angle. We present physical relationship between the three bands using the photometric and the polarimetric properties of the sources.

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1980 센서스 인구의 연령구조에 의한 최근 출생 및 사망률의 추정

  • Choi, Don;Lee, Si-Baek
    • Korea journal of population studies
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    • v.5 no.1
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    • pp.99-116
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    • 1982
  • The historical study reveals that our ancestors had maintained a system which could produce data on population and households. The main purposes of maintaing the system at that time were taxation and conscription. At the present time, however, there are three major data sources which produce the statistics on pop-ulation and households in Korea : Civil Registration System, Resident Registration System and Popula-tion Census. These three systems are found to have some problems. there are some inherent problems in the regis-tration systems, such as problems in its coverage, accuracies in contents and timeliness in reporting the vital events and publishing the results. The population census has also non- sampling erors, such as errors in coverage, respone and non-response. Apart from the above mentioned problems, there are also conflicting problems arised from having three data sources, We can find some overlapping problems and difficulties in comparative studies. In the future, these problems should be considered for the improvement of the quality of statistics on population and household.

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Calculation of Material Properties with JMatPro for the Process Simulation (JMatPro를 이용한 공정해석에서의 물성계산)

  • Lee, Kyung-Hoon;Kang, Gyeong-Pil
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2008.05a
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    • pp.142-145
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    • 2008
  • Process simulation requires accurate and reliable data for a wide variety of material properties, ranging from thermal conductivity to flow stress curves. Traditionally such data are gathered from experimental sources, which has significant disadvantages in that not all of the required data is readily available, it may be from various sources that are themselves inconsistent, measurement of high temperature properties is expensive, and furthermore the properties can be sensitive to microstructure as well as to alloy composition. This article describes the development of a new multi-platform software program called JMatPro, which is based on CALPHAD methodology, for calculating the properties and behavior of multi-component alloys. A feature of the JMatPro is that the calculations are based on sound physical principles rather than purely statistical methods. Thus, many of the shortcomings of methods such as regression analysis can be overcome.

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Geostatistical Integration of Different Sources of Elevation and its Effect on Landslide Hazard Mapping

  • Park, No-Wook;Kyriakidis, Phaedon C.
    • Korean Journal of Remote Sensing
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    • v.24 no.5
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    • pp.453-462
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    • 2008
  • The objective of this paper is to compare the prediction performances of different landslide hazard maps based on topographic data stemming from different sources of elevation. The geostatistical framework of kriging, which can properly integrate spatial data with different accuracy, is applied for generating more reliable elevation estimates from both sparse elevation spot heights and exhaustive ASTER-based elevation values. A case study from Boeun, Korea illustrates that the integration of elevation and slope maps derived from different data yielded different prediction performances for landslide hazard mapping. The landslide hazard map constructed by using the elevation and the associated slope maps based on geostatistical integration of spot heights and ASTER-based elevation resulted in the best prediction performance. Landslide hazard mapping using elevation and slope maps derived from the interpolation of only sparse spot heights showed the worst prediction performance.

Statistical micro matching using a multinomial logistic regression model for categorical data

  • Kim, Kangmin;Park, Mingue
    • Communications for Statistical Applications and Methods
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    • v.26 no.5
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    • pp.507-517
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    • 2019
  • Statistical matching is a method of combining multiple sources of data that are extracted or surveyed from the same population. It can be used in situation when variables of interest are not jointly observed. It is a low-cost way to expect high-effects in terms of being able to create synthetic data using existing sources. In this paper, we propose the several statistical micro matching methods using a multinomial logistic regression model when all variables of interest are categorical or categorized ones, which is common in sample survey. Under conditional independence assumption (CIA), a mixed statistical matching method, which is useful when auxiliary information is not available, is proposed. We also propose a statistical matching method with auxiliary information that reduces the bias of the conventional matching methods suggested under CIA. Through a simulation study, proposed micro matching methods and conventional ones are compared. Simulation study shows that suggested matching methods outperform the existing ones especially when CIA does not hold.

Energy-Efficient Multipath Routing Protocol for Supporting Mobile Events in Wireless Sensor Networks (무선 센서 네트워크에서 이동 이벤트를 지원하기 위한 에너지 효율적인 멀티패스 라우팅 프로토콜)

  • Kim, Hoewon;Lee, Euisin
    • KIPS Transactions on Computer and Communication Systems
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    • v.5 no.12
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    • pp.455-462
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    • 2016
  • Wireless sensor networks have been researched to gather data about events on sensor fields from sources at sinks. Multipath routing is one of attractive approaches to reliably send data against the problem of frequent breakages on paths from sources to sinks due to node and link failures. As mobile events such as humans, animals, and vehicles are considered, sources may be continuously generated according to the movement of the mobile event. Thus, mobile events provide new challenging issue in multipath routing. However, the research on multipath routing mainly focus on both efficient multipath construction from sources to static sinks and fast multipath reconstruction against path breakages. Accordingly, the previous multipath routing protocols request each source continuously generated by a mobile event to construct individual multipath from the source to sinks. This induces the increase of multipath construction cost in the previous protocols in proportion to the number of source. Therefore, we propose efficient multipath routing protocol for supporting continuous sources generated by mobile events. In the proposed protocol, new source efficiently reconstructs its multipath by exploiting the existing multipath of previous sources. To do this, the proposed protocol selects one among three reconstruction methods: a local reconstruction, a global partial one, and a global full one. For a selection decision, we provide an analytical energy consumption cost model that calculates the summation of both the multipath reconstruction cost and the data forwarding cost. Simulation results show that the proposed protocol has better performance than the previous protocol to provide multipath routing for mobile events.

Toward Research Collaboration Between Korea and Russia: KSGPC's Research Activities and Corporational Issues in Geomatics

  • KIM, Kam-Lea;LEE, Ho-Nam;KIM, Uk-Nam
    • Korean Journal of Geomatics
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    • v.3 no.2
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    • pp.81-86
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    • 2004
  • In recent years, the importance of geospatial data have been emphasized not only for the national GIS programs and but also in the value added commercial and industry markets. There is no doubt that GIS, GPS, aerial and satellite imagery data were provided powerful tools to support national information infrastructure for geospatial database. While great emphasis has been laid on the geospatial data, there has been little analysis or evaluation of how to maximize the benefits of using these information sources. Also, with the proliferation of geographic data and information sources such as satellite imagery, digital aerial photograph, digital topographic and vector data, there is a great need to inform professionals from all disciplines as to the benefits of these information sources and how to best put them to use within any given application. From the first publication of KSGPC(Korean Society of Geodesy, Photogrammetry and Cartography) papers in 1981, our objective was, and is, to help develop the wider spectrum of GIS in the academy and industry by exposing new users to the benefits of GIS, remote sensing, mapping, GPS and photogrammetry. In this presentation, we will introduce KSGPC works and will evaluate GIS-related governmental policies and programs in Korea for the past and the future to present different status between Korea and Russia. It is now important to investigate lessons learnt from two countries' experiences and developed an empirical framework to combine outcome from GIS-related researches in Korea and Russia. This may enable GIS professionals to gain a wider range of experiences in the international context, and consequently, help them to develop new markets for GIS. Therefore, we arranged the possible action items and interesting points to corporate and to promote the academic growth in the practice of GIS.

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Estimation of Geometric Error Sources of Suspension Bridge using Survey Data (측량 데이터를 이용한 현수교의 형상오차 원인 추정)

  • Park, Yong Myung;Cho, Hyun Jun;Cheung, Jin Hwan;Kim, Nam Sik
    • Journal of Korean Society of Steel Construction
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    • v.19 no.3
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    • pp.313-321
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    • 2007
  • The study discussed in this paper presents a method of estimating sources of geometric errors in suspension bridges in use, based on geometric survey data. A geometric error is defined as the difference between the survey data and the design geometry of a main cable. It is assumed that the geometric error in a suspension bridge is caused by the variations in the weight of the stiffening girder and the deformation of the anchorage foundations due to the creep of soil. The variations in the girder weight and the deformation of the foundation were estimated by constructing a matrix of factors that affect suspension bridges due to the variations. To check the validity of the proposed method, it was applied to the Kwang-An Bridge, and the sources of geometric errors in the bridge were estimated using the survey data.