• Title/Summary/Keyword: Derived data

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Improving Satellite Derived Soil Moisture Data Using Data Assimilation Methods (자료동화 기법을 이용한 위성영상 추출 토양수분 자료 개선)

  • Hwang, Soonho;Ryu, Jeong Hoon;Kang, Moon Seong
    • Proceedings of the Korea Water Resources Association Conference
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    • 2018.05a
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    • pp.152-152
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    • 2018
  • Soil moisture is a important factor in hydrologic analysis. So, if we have spatially distributed soil moisture data, it can help to study much research in a various field. Recently, there are a lot of satellite derived soil moisture data, and it can be served through web freely. Especially, NASA (National Aeronautics and Space Administration) launched the Soil Moisture Aperture Passive (SMAP) satellite for mapping global soil moisture on 31 January 2015. SMAP data have many advantages for study, for example, SMAP data has higher spatial resolution than other satellited derived data. However, becuase many satellited derived soil moisture data have a limitation to data accuracy, if we have ancillary materials for improving data accuracy, it can be used. So, in this study, after applying the alogorithm, which is data assimilation methods, applicability of satellite derived soil moisture data was analyzed. Among the various data assimilation methods, in this study, Model Output Statistics (MOS) technique was used for improving satellite derived soil moisture data. Model Output Statistics (MOS) is a type of statistical post-processing, a class of techniques used to improve numerical weather models' ability to forecast by relating model outputs to observational or additional model data.

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A Modelling of Multi-derived Data and Its Retrieval Scheme (복합생성 자료검색의 모형화)

  • Lee, Chun-Yeol
    • Asia pacific journal of information systems
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    • v.4 no.1
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    • pp.115-138
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    • 1994
  • Current database systems are based on the assumption that a datum denotes the same meaning; however, in reality, the violation of this assumption is not unusual. Some data are created in such a way that they represent different sets of attribute values. The current research formulates this phenomenon as dissimilarities of derivation rules and defines multi-derived data as ones that are derived by multiple rules. For multi- derived data, this research proposes a new retrieval scheme and analyze its implication with relation to data retrieval.

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Deriving Basic Living Service Items and Establishing Spatial Data in Rural Areas (농촌 생활권 기초생활서비스 항목 설정 및 공간데이터 구축을 위한 기초연구)

  • Kim, Suyeon;Kim, Sang-Bum
    • Journal of the Korean Institute of Rural Architecture
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    • v.24 no.3
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    • pp.39-46
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    • 2022
  • This study aims to derive basic living service facility items in rural areas and construct related spatial data. To do this, a literature review on the laws and systems related to the residential environment and services in rural areas, rural spatial planning, and the 'Rural Convention' strategic plan reports for the Jeolla and Gyeongsang Region in 2021 was conducted. Primary data collection and review on the list of basic living service items in rural areas derived from the analysis were conducted. After data collection, 12 sectors and 44 types of rural basic living service items were derived; the data selection was carried out based on the clarity of the subject of data management, whether it was established nationwide, whether it was disclosed and provided, whether it was periodically updated, and whether it was an underlying law. Afterwards, data on the derived rural basic living service items were constructed. Afterwards, spatial data on the derived rural basic living service items were constructed. Because open data provided through various institutions were employed, data structure unification such as data attribute values and code names was needed, and abnormal data such as address errors and omissions were refined. After that, the data provided in text form was converted into spatial data through geocoding, and through comparative review of the distribution status of the converted data and the provided address, spatial data related to rural basic living services were finally constructed for about 540,000 cases. Finally, implications for data construction for diagnosing rural living areas were derived through the data collection and construction process. The derived implications include data unification, data update system establishment, the establishment of attribute values necessary for rural living area diagnosis and spatial planning, data establishment plan for facilities that provide various services, rural living area analysis method, and diagnostic index development. This study is meaningful in that it laid the foundation for data-based rural area diagnosis and rural planning, by selecting the basic rural living service items, and constructing spatial data on the selected items.

Functional Requirements of Data Repository for DMP Support and CoreTrustSeal Authentication

  • Kim, Sun-Tae
    • International Journal of Knowledge Content Development & Technology
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    • v.10 no.1
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    • pp.7-20
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    • 2020
  • For research data to be shared without legal, financial and technical barriers in the Open Science era, data repositories must have the functional requirements asked by DMP and CoreTrustSeal. In order to derive functional requirements for the data repository, this study analyzed the Data Management Plan (DMP) and CoreTrustSeal, the criteria for certification of research data repositories. Deposit, Ethics, License, Discovery, Identification, Reuse, Security, Preservation, Accessibility, Availability, and (Meta) Data Quality, commonly required by DMP and CoreTrustSeal, were derived as functional requirements that should be implemented first in implementing data repositories. Confidentiality, Integrity, Reliability, Archiving, Technical Infrastructure, Documented Storage Procedure, Organizational Infrastructure, (Meta) Data Evaluation, and Policy functions were further derived from CoreTrustSeal. The functional requirements of the data repository derived from this study may be required as a key function when developing the repository. It is also believed that it could be used as a key item to introduce repository functions to researchers for depositing data.

Deriving the Properties of Object Types for Research Data Relation Model

  • Kim, Suntae
    • Journal of Information Science Theory and Practice
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    • v.1 no.2
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    • pp.84-92
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    • 2013
  • In this study, the properties of the object types required to describe the relationship among research data resources, which may be generated during the life cycle of the research, are derived. The properties of Fedora Commons and DSpace, which are open source software used for resource management, and schema properties published in DataCite were analyzed. Based on relation names of Fedora Commons, nine new relation names were derived. Thirty-eight object type properties consolidating the target properties of the analysis were derived. The result of this study can be used as basic material for crosswalk research studies of object type relation terms to ensure interoperability among the systems.

A Study on the Derivation of the Unit Hydrograph using Multiple Regression Model (다중회귀모형으로 추정된 모수에 의한 최적단위유량도의 유도에 관한 연구)

  • 이종남;김채원;황창현
    • Water for future
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    • v.25 no.1
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    • pp.93-100
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    • 1992
  • A study on the Derivation of the Unit Hydrograph using Multiple Regression Moe이. The purpose of this study is to deriver an optimal unit hydrograph suing the multiple regression model, particularly when only small amount of data is available. The presence of multicollinearity among the input data can cause serious oscillations in the derivation of the unit hydrograph. In this case, the oscillations in the unit hydrograph ordinate are eliminated by combining the data. The data used in this study are based upon the collection and arrangement of rainfall-runoff data(1977-1989) at the Soyang-river Dam site. When the matrix X is the rainfall series, the condition number and the reciprocal of the minimum eigenvalue of XTX are calculated by the Jacobi an method, and are compared with the oscillation in the unit hydrograph. The optimal unit hydrograph is derived by combining the numerous rainfall-runoff data. The conclusions are as follows; 1)The oscillations in the derived unit hydrograph are reduced by combining the data from each flood event. 2) The reciprocals of the minimum eigen\value of XTX, 1/k and the condition number CN are increased when the oscillations are active in the derived unit hydrograph. 3)The parameter estimates are validated by extending the model to the Soyang river Dam site with elimination of the autocorrelation in the disturbances. Finally, this paper illustrates the application of the multiple regression model to drive an optimal unit hydrograph dealing with the multicollinearity and the autocorrelation which cause some problems.

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EVALUATION OF GFDL GCM CLIMATE VARIABILITY USING EOFS OF ZONAL AVERAGE TEMPERATURE DATA

  • Yoo, Chul-sang
    • Water Engineering Research
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    • v.5 no.2
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    • pp.69-79
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    • 2004
  • In this study the GFDL GCM generated (controlled run) zonal average temperature data are evaluated by comparing their EOFs with those from observed data. Even though the correlation matrices of observed and simulated data are shown significantly different (Polyak and North, 1997b), the EOFs derived are found very similar with very high pattern correlations. This means almost all the information (second-order statistics) derived from the observed data can be reproduced by the EOFs derived from the GFDL GCM simulates. Also, the EOFs from GFDL GCM were found to have more flexible structures than those from the observed. Thus, we may conclude that the GFDL GCM can simulate the Earth's energy balance system reasonably. However, more in detail research should be focused on the effect from various forcings on climate variability, as, in some cases, the effect of external forcings could shadow the system characteristics and mislead the simulation results.

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Regional sea water chlorophyll distribution derived from MODIS for near-real time monitoring

  • Liew, S.C.;Heng, A.W.C.
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.1039-1041
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    • 2003
  • Ocean color products derived from remote sensing satellite data are useful for monitoring the sea water quality such as the concentrations of chlorophyll, sediments and dissolved organic matter. Currently, ocean color products derived from MODIS data can be requested from NASA over the internet. However, due to the bandwidth limitation of most users in this region, and the time delay in data delivery, the products cannot be use for near-real time monitoring of sea water chlorophyll. CRISP operates a MODIS data receiving station for environmental monitoring purposes. MODIS data have been routinely received and processed to level 1B. We have adapted the higher level processing algorithms from the Institutional Algorithms provided by NASA to run in a standalone environment. The implemented algorithms include the MODIS ocean color algorithms. Seasonal chlorophyll concentration composite can be compiled for the region. By comparing the near-real time chlorophyll product with the seasonal composite, anomaly in chlorophyll concentration can be detected.

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Study of Digital Analysis Efficiency through a Complexity Analysis (복잡성 분석을 통한 디지털 분석의 유효성에 관한 연구)

  • 이혁준;이종석
    • Korean Institute of Interior Design Journal
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    • no.31
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    • pp.56-63
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    • 2002
  • This study intends to prepare a system that can be used, by applying digital technique, in analyzing complexity of architectural forms that have been visualized by the correlation based on the distribution chart made in accordance with profile lines. The profile lines are derived from the edge analysis of the architectural forms, simplified based on the visual theory. For the purpose, this study was conducted in the following ways: First, problems of the existing models for the elevation analysis were examined along with formal analysis based on visual recognition to consider the profile lines derived from the forms. Secondly, in elevation analysis, profile lines were derived by digital method to measure them qualitatively. To verify the objectivity of the measured data value, a survey was conducted based on the adjective cataloging method, and the correlation of the survey result and analyzed data was analyzed to verify the validity of the derived data. Thirdly, supplementation for the problems deducted from experiments and the possibility to use it in designing were suggested. Digital method has many advantages over the conventional analyzing system in deriving precise data value by excluding subjectivity. It also allows various analytical methods in analyzing numerous data repeatedly. Diversified models and methods of analysis considering numerous factors arising in the process of designing remain assignments to research in future.

Protulactones A and B: Two New Polyketides from the Marine-derived Fungus Aspergillus sp. SF-5044

  • Sohn, Jae-Hak;Oh, Hyun-Cheol
    • Bulletin of the Korean Chemical Society
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    • v.31 no.6
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    • pp.1695-1698
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    • 2010
  • Protulactones A (1) and B (2), two new polyketide-derived fungal metabolites, have been isolated from an EtOAc extract of the marine-derived fungus Aspergillus sp. SF-5044 by various chromatographic methods. The structures of 1 and 2 were mainly determined by analysis of the NMR spectroscopic data and MS data, along with chemical methods such as Mosher method. Protulactones A (1) and B (2) are new members of polyketide-derived secondary metabolites, possessing unique ring systems among the fungal metabolites produced by the genus Aspergillus.