• Proceedings of the Korean Society of Precision Engineering Conference
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• 1993.04b
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• pp.262-266
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• 1993

The development of COPS(Computer aided Operation Planning System) needs data mapping paradigm which provides intelligent determonation of cutting conditions from the requirements of process planning side. We proposed the idea of multi-level mapping by the combination of heuristics of domain experts and mathematical abstraction of cutting condition and requirements. Mathematical mathods for the generalization of heuristics were constructed by multi-layer perceptron. DBMS for determination of cutting conditions was constructed by classification and combination of best fitted models. Triangular fuzzy number was used to process the uncertainties in heuristics of experts.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.32B no.1
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• pp.1-10
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• 1995

A graphic user interface for effectively browsing object-oriented databases in complex applications is designed and implemented. The rationale behind our design lies in enabling the users of various levels and needs to investigate the database according to their respective interests and desired depths. A novel idea in our design is the introduction of zooming techniques from a logical view, which vidualize the backbone abstraction concepts of the object-oriented data model. These objectives are verified by evaluating the results of its implementation.

• Journal of Korea Water Resources Association
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• v.48 no.6
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• pp.491-500
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• 2015

In order to improve the runoff estimation accuracy of the Natural Resources Conservation Service (NRCS) curve number (CN) model, this study incorporated rainfall and maximum potential retention as contributors for initial abstraction. The modification was proposed based on 658 rank-order data of rainfall and subsequent runoff from 15 watersheds. The NRCS-CN model (M1), one of its inspired modified model (M2), and the proposed model (M3) were analyzed employing different CN approaches. Using tabulated, calculated and least squares fitted CNs ($CN_T$, $CN_C$, $CN_{LSF}$, respectively), the models' performances were evaluated based on Root Mean Square Error (RMSE), Nash-Sutcliffe Efficiency (NSE), and Percent Bias (PBIAS). Applications of model M1, M2, and M3, respectively exhibited watershed cumulative mean [RMSE (23.60, 18.12, 16.04), NSE (0.54, 0.73, 0.79), and PBIAS (36.54, 20.25, 12.00)]. Similarly, using CNC (for M1 and M2 model) and $CN_{LSF}$ (for M3 model), the performance of three models respectively were assessed based on watershed cumulative mean [RMSE (17.17, 15.88, 13.82), NSE (0.76, 0.80, 0.85), and PBIAS (3.06, 4.47, 0.11)]. The proposed model (M3) that linked all of the NRCS-CN variants showed more statistically significant agreement between the observed and estimated data.

• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.1
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• pp.65-73
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• 2019

The MODIS (Moderate Resolution Imaging Spectroradiometer) data in Hierarchical Data Format (HDF) have been processed using the Geospatial Data Abstraction Library (GDAL). Because of a relatively large data size, it would be preferable to build and install the data analysis tool with greater computing performance, which would differ by operating system and the form of distribution, e.g., source code or binary package. The objective of this study was to examine the performance of the GDAL for processing the HDF files, which would guide construction of a computer system for remote sensing data analysis. The differences in execution time were compared between environments under which the GDAL was installed. The wall clock time was measured after extracting data for each variable in the MODIS data file using a tool built lining against GDAL under a combination of operating systems (Ubuntu and openSUSE), compilers (GNU and Intel), and distribution forms. The MOD07 product, which contains atmosphere data, were processed for eight 2-D variables and two 3-D variables. The GDAL compiled with Intel compiler under Ubuntu had the shortest computation time. For openSUSE, the GDAL compiled using GNU and intel compilers had greater performance for 2-D and 3-D variables, respectively. It was found that the wall clock time was considerably long for the GDAL complied with "--with-hdf4=no" configuration option or RPM package manager under openSUSE. These results indicated that the choice of the environments under which the GDAL is installed, e.g., operation system or compiler, would have a considerable impact on the performance of a system for processing remote sensing data. Application of parallel computing approaches would improve the performance of the data processing for the HDF files, which merits further evaluation of these computational methods.

• Proceedings of the Korea Contents Association Conference
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• 2009.05a
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• pp.770-775
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• 2009

Along with the advance of USN technology in a human-oriented informatization society these days, society is quickly changing into a ubiquitous computing society in which information even between objects can be organically combined and utilized. In order to successfully build such a ubiquitous computing society, it is indispensable to have core USN technologies such as USN sensor nodes, sensor networks, USN middleware, and USN applied services that efficiently manage sensing information collected from sensor nodes, and support the abstraction function for the composition of sensor networks. In order to process the transmission event of sensing values that are generated from various USN terminal devices, this study designs a process that performs the abstraction of data for the efficient process of diverse sensing values transferred from USN and RFID terminal devices.

• Journal of Korean Society for Geospatial Information Science
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• v.17 no.1
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• pp.167-174
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• 2009

A Tile Map Service is a regular map service that has been enhanced to serve maps very quickly using a cache of static images. The map cache is a directory that contains image tiles of a map extent at specific scale levels. Returning a tile from the cache takes the server much less time than drawing the map image on demand. Use of a Tile Map Service can dramatically improve the time that clients take to display complex base-maps. Using Tile Map Services thus eliminate the need to trade quality for performance. This study provides a way to construct Tile Map Service System using Open Source GIS. We used GDAL(Geospatial Data Abstraction Library) which is one of the Open Source GIS Softwares to make Tile Map Image and OpenLayers to publish Web Page. Moreover, We conducted a performance test on Tile Map System and Dynamic Map System and evaluated the results of it. As a result, the proposed method makes it easier to construct high performance Tile Map Service using Open Source GIS without commercial products.

• Journal of Information Technology Applications and Management
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• v.23 no.3
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• pp.1-12
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• 2016

Visual representations for concepts in business management are quite challenging, especially those abstract concepts in Accountancy discipline. For example, there might not be a consensus on what to use to represent such abstraction as an asset, liability, or owner equity. This is because asset can be property, estate, resources, equipment, or any tangible or non-tangible valuables. Cognitive science concepts and behavior engagement have been used to develop visual representations for financial data. The concepts include spatial processing, big picture thinking, and metaphor. Review of past studies together with a brief research plan to test the usability for learning of four new augmented reality 0visuals are provided in the present paper.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.1B
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• pp.53-61
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• 2010

M2M Platform is the future ubiquitous network technologies which provide the integrated service with the networks and devices. It requires the standardized message protocols among the sensor applications. In this study, we developed the message protocols that support the data abstraction and interoperability among application systems with characteristics of sensor systems. The message protocols consist of the data representation formats and data exchange functions.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.4 no.2
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• pp.154-173
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• 2010

Database outsourcing is unavoidable in the near future. In the scenario of data stream outsourcing, the data owner continuously publishes the latest data and associated authentication information through a service provider. Clients may register queries to the service provider and verify the result's correctness, utilizing the additional authentication information. Research on On-line Stream Analytics (OLSA) is motivated by extending the data cube technology for higher multi-level abstraction on the low-level-abstracted data streams. Existing work on OLSA fails to consider the issue of database outsourcing, while previous work on stream authentication does not support OLSA. To close this gap and solve the problem of OLSA query authentication while outsourcing data streams, we propose MDAHRB and MDAHB, two multi-dimensional authentication approaches. They are based on the general data model for OLSA, the stream cube. First, we improve the data structure of the H-tree, which is used to store the stream cube. Then, we design and implement two authentication schemes based on the improved H-trees, the HRB- and HB-trees, in accordance with the main stream query authentication framework for database outsourcing. Along with a cost models analysis, consistent with state-of-the-art cost metrics, an experimental evaluation is performed on a real data set. It exhibits that both MDAHRB and MDAHB are feasible for authenticating OLSA queries, while MDAHRB is more scalable.

• The Journal of Society for e-Business Studies
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• v.24 no.4
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• pp.17-30
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• 2019

The rapid development of a software-core society emphasizes the importance of software competence as a basic condition for all academic disciplines. The purpose of this study is to investigate the difference of perceptions among students of basic software education which is currently being conducted in university. The results of applying the nine core elements of Computational Thinking for Problem Solving to the learners of the each majors are as follows. In humanities, learners mainly applied the elements of Data Collection, Problem Decomposition and Automation. On the other hand, natural science department learners mainly applied the elements of Data Analysis, Algorithm and Automation. In addition, arts learners mainly applied elements of Data Representation, Abstraction, and Automation. To apply Computational Thinking to the development of software, humanities learners mainly applied elements of Data Collection, Algorithm, Automation. On the other hand, natural science department learners mainly applied the elements of Data Analysis, Algorithm and Automation. In addition, arts learners mainly applied elements of Data Representation, Abstraction, and Automation. Based on the results of this study, it is expected that the educational effectiveness of the learner will be maximized by including the learner analysis with each majors in the design of the basic software curriculum that each university is conducting.