• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.38 no.2
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• pp.153-163
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• 2020

After launching the GOCE (Gravity Field and Steady-State Ocean Circulation Explorer) which obtains high-frequency gravity signal using a gravity gradiometer, many research institutes are concentrating on the development of GGM (Global Geopotential Model) based on GOCE data and evaluating its precision. The precision of some GGMs was also evaluated in Korea. However, some studies dealt with GGMs constructed based on initial GOCE data or others applied a part of GNSS (Global Navigation Satellite System) / Leveling data on UCPs (Unified Control Points) for the precision evaluation. Now, GGMs which have a higher degree than EGM2008 (Earth Gravitational Model 2008) are available and UCPs were fully established at the end of 2019. Thus, EIGEN-6C4 (European Improved Gravity Field of the Earth by New techniques - 6C4), GECO (GOCE and EGM2008 Combined model), XGM2016 (Experimental Gravity Field Model 2016), SGG-UGM-1, XGM2019e_2159 were collected with EGM2008, and their precisions were assessed based on the GNSS/Leveling data on UCPs. Among GGMs, it was found that XGM2019e_2159 showed the minimum difference compared to a total of 5,313 points of GNSS/Leveling data. It is about a 1.5cm and 0.6cm level of improvement compare to EGM2008 and EIGEN-6C4. Especially, the local biases in the northern part of Gyeonggi-do, Jeju island shown in the EGM2008 was removed, so that both mean and standard deviation of the difference of XGM2019e_2159 to the GNSS/Leveling are homogeneous regardless of region (mountainous or plain area). NGA (National Geospatial-Intelligence Agency) is currently in progress in developing EGM2020 and XGM2019e_2159 is the experimentally published model of EGM2020. Therefore, it is expected that the improved GGM will be available shortly so that it is necessary to verify the precision of new GGMs consistently.

• International Journal of Naval Architecture and Ocean Engineering
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• v.8 no.4
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• pp.301-311
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• 2016

This paper describes the whole procedures to determine ice-induced global loads on the ship using measured full-scale data in accordance with the method proposed by the Canadian Hydraulics Centre of the National Research Council of Canada. Ship motions of 6 degrees of freedom (dof) are found by processing the commercial sensor signals named Motion Pak II under the assumption of rigid body motion. Linear accelerations as well as angular rates were measured by Motion Pak II data. To eliminate the noise of the measured data and the staircase signals due to the resolution of the sensor, a band pass filter that passes frequencies between 0.001 and 0.6 Hz and cubic spline interpolation resampling had been applied. 6 dof motions were computed by the integrating and/or differentiating the filtered signals. Added mass and damping force of the ship had been computed by the 3-dimensional panel method under the assumption of zero frequency. Once the coefficients of hydrodynamic and hydrostatic data as well as all the 6 dof motion data had been obtained, global ice loads can be computed by solving the fully coupled 6 dof equations of motion. Full-scale data were acquired while the ARAON rammed old ice floes in the high Arctic. Estimated ice impact forces for two representative events showed 7e15 MN when ship operated in heavy ice conditions.

• Journal of Information Management
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• v.39 no.2
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• pp.211-234
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• 2008

Recently, the frequency and scale of natural disasters such as typhoons, flood, earthquakes, and tidal waves from earthquakes has been increasing. Several nations have recognized that earth observation is essential for protecting the Earth's environment. However, as the data format from earth observation varies depending on areas, institutes, and countries, sharing and exchange between data is difficult. Thus, we have a metadata standardization scheme suitable for the domestic situation to allow exchange of data between societal benefit areas with reference to principles of data sharing and exchange that are discussed on GEO (Group on Earth Observation). We have also designed metadata schemes required to identify the metadata situation of earth observation data being used for 9 societal benefit areas of GEOSS(Global Earth Observation System of Systems).

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.60-62
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• 2003

The concept of a Spatial Data Infrastructure (SDI) has emerged globally to facilitate the transit of spatial information from data producers to a vast and ever-growing community of users. SDI have become very important in determining the way in which spatial data are used throughout an organization, a nation, different regions, and the world. SDI is an initiative intended to create an environment in which all stakeholders can cooperate with each other and interact with technology, to better achieve their objectives at different political / administrative levels. Islamic Republic of Iran began her participation in the Global map project and SDI activities in 1998. In this related, National Cartographic Center (NCC), as the representative of Iran, started the job with identifying the suitable sources of data for creation of those layers stated in the specifications of Global Mapping. NCC started making GIS Users Councils (National & Provincial Councils) for the making National SDI and Local SDI too. Now, NCC is doing some activities to joining its National SDI to Regional and Global SDI. This paper in first section, discuss about SDI as basic point in Information Technology (IT). In second section, SDI situation in IRAN and National Cartographic Center’s roles in realization of future scope of RSDI and GSDI is discussed. (NCC is one of the greatest Map Producer organizations in IRAN). The way that be applied, is analyzing of fundamental points especially Sustainable development, IT and SDI and their complementing policy in Information Society. These include some applications in National, Regional and Global levels.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.46 no.4
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• pp.15-31
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• 2023

In this study, we propose a novel approach to analyze big data related to patents in the field of smart factories, utilizing the Latent Dirichlet Allocation (LDA) topic modeling method and the generative artificial intelligence technology, ChatGPT. Our method includes extracting valuable insights from a large data-set of associated patents using LDA to identify latent topics and their corresponding patent documents. Additionally, we validate the suitability of the topics generated using generative AI technology and review the results with domain experts. We also employ the powerful big data analysis tool, KNIME, to preprocess and visualize the patent data, facilitating a better understanding of the global patent landscape and enabling a comparative analysis with the domestic patent environment. In order to explore quantitative and qualitative comparative advantages at this juncture, we have selected six indicators for conducting a quantitative analysis. Consequently, our approach allows us to explore the distinctive characteristics and investment directions of individual countries in the context of research and development and commercialization, based on a global-scale patent analysis in the field of smart factories. We anticipate that our findings, based on the analysis of global patent data in the field of smart factories, will serve as vital guidance for determining individual countries' directions in research and development investment. Furthermore, we propose a novel utilization of GhatGPT as a tool for validating the suitability of selected topics for policy makers who must choose topics across various scientific and technological domains.

• Journal of Astronomy and Space Sciences
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• v.27 no.4
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• pp.367-375
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• 2010

In this study, we compared the precipitable water vapor (PWV) data derived from the radiosonde observation data at Sokcho Observatory and the PWV data at Sokcho Global Positioning System (GPS) Observatory provided by Korea Astronomy and Space Science Institute, from 0000 UTC, June 1, 2007 to 1200 UTC, May 31, 2009, and analyzed the radiosonde bias between the day and the night. In the scatter diagram of the daytime and nighttime radiosonde PWV data and the GPS PWV data, dry bias was found in the daytime radiosonde observation as known in the previous study. In addition, for all the rainfall events, the tendency that the wet bias of the radiosonde PWV increased as the GPS PWV decreased and the dry bias of the radiosonde PWV increased as the GPS PWV increased was significantly less distinctive in nighttime than in daytime. The quantitative analysis of the bias and error of the radiosonde PWV data showed that the mean bias decreased in the second year, regardless of nighttime or daytime rainfall, and the non-rainfall root mean square error (RMSE) was similar to that of the previous studies, while the rainfall RMSE was larger to a certain extent.

• Journal of the Society of Naval Architects of Korea
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• v.52 no.2
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• pp.110-118
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• 2015

Weather routing method is one of the best practices of SEEMP (Ship Energy Efficiency Management Plan) for fuel-efficient operation of ship. KR is carrying out a basic research for development of the weather routing algorithm and making a monitoring system by FOC (Fuel Oil Consumption) analysis compared to the reference, which is the great circle route. The added resistances applied global sea/weather data can be calculated using ship data, and the results can be corrected to ship motions. The global sea/weather data such as significant wave height, ocean current and wind data can be used to calculate the added resistances. The reference route in a usual navigation is the great circle route, which is the shortest distance route. The global sea/weather data can be divided into grids, and the nearest grid data from a ship's position can be used to apply a ocean going vessel's sea conditions. Powell method is used as an optimized routing technique to minimize FOC considered sea/weather conditions, and FOC result can be compared with the great circle route result.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.5 no.1
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• pp.51-64
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• 1995

In distributed environments, the DB secure models have been being studied to include the multi-level mechanism which is effective to control access according to the level of the data value. These mechanisms have the problems. The first, it is impossible to maintain the global data which is protected in the multi-level mechanism. The second, the access and the relation of the data is not clear due to the access revocation between the local data and the global's. In this paper, we proposed the mechanism using shema. The mechanism doesn't have the access revocation, and provides the protection of the data and the control to the global data.

• Proceedings of the Korean Society of Computer Information Conference
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• 2024.01a
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• pp.453-454
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• 2024

본 연구는 경기 변동에 따라 대중들의 소비가 민감한 사업군을 도출해내고, 서울시 열린데이터 광장의 소비데이터를 분석하여 해당 기업의 경영 전략을 제시하는데 목적이 있다. 2023년 물가지수(CPI)는 8월 3.4%, 9월 3.7%, 10월 3.8%로 유례없는 상승 추이를 보이고 있다. 또한, KDI(한국개발연구원)는 2024년 소비는 고물가 기조로 인하여 상품소비의 부진이 지속되어 기업 매출이 전년(1.9%)과 유사하게 1.8% 증가하는데 그칠 전망이라고 예측하였다. 이렇게 대중들의 소비가 줄어들고 있는 경기 상황에서 기업이 손실을 막기 위해 취할 수 있는 대응 전략을 수립하는데 이 연구가 도움이 되리라고 사료된다.

• Journal of Korea Society of Digital Industry and Information Management
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• v.5 no.4
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• pp.99-108
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• 2009

In the security environments of heterogeneous multidatabase systems, not only the existing local autonomy but also the security autonomy as a new constraint are required. From global aspects, transactions maintain consistent data value when they assure serializability. Also, secure properties must protect these transactions and data values to prevent direct or indirect information effluence. This paper proposes scheduling algorithm for global transactions to ensure multilevel secure one-copy quasi-serializability (MLS/1QSR) in security environments of multidatabase systems with replicated data and proves its correctness. The proposed algorithm does not violate security autonomy and globally guarantees MLS/1QSR without indirect information effluence in multidatabase systems.