• Journal of KIISE:Computer Systems and Theory
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• v.35 no.1
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• pp.1-17
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• 2008

Recently, the object based storage devices systems(OSDs) have been actively researched. They are different from existing block based storage systems(BSDs) in terms of the storage unit. The storage unit of the OSDs is an object that includes the access methods, the attributes of data, the security information, and so on. The object has no size limit and no influence on the internal storage structures. Therefore, the OSDs improve the I/O throughput and the scalability. But the backup systems for the OSDs still use the existing backup techniques for the BSDs. As a result, they need much backup time and do not utilize the characteristics of the OSDs. In this paper, we design and implement a new object based backup system that utilizes the features of the OSDs. Our backup system significantly improves the backup time over existing backup systems because the raw objects are directly transferred to the backup devices in our system. It also restores the backup data much faster than the existing systems when system failures occur. In addition, it supports various types of backup and restore requests.

• Korean Journal of Remote Sensing
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• v.30 no.1
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• pp.137-147
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• 2014

We proposed and verified the methods to maintain data qualities as well as to reduce data volume for the Geostationary Ocean Color Imager (GOCI), the world's first ocean color sensor operated in geostationary orbit. For the GOCI level-2 data, 92.9% of data volume could be saved by only the data compression. For the GOCI level-1 data, however, just 20.7% of data volume could be saved by the data compression therefore another approach was required. First, we found the optimized number of bits per a pixel for the GOCI level-1 data from an idea that the quantization bit for the GOCI (i.e. 12 bit) was less than the number of bits per a pixel for the GOCI level-1 data (i.e. 32 bit). Experiments were conducted using the $R^2$ and the Modulation Transfer Function (MTF). It was quantitatively revealed that the data qualities were maintained although the number of bits per a pixel was reduced to 14. Also, we performed network simulations using the Network Simulator 2 (Ns2). The result showed that 57.7% of the end-toend delay for a GOCI level-1 data was saved when the number of bits per a pixel was reduced to 14 and 92.5% of the end-to-end delay for a GOCI level-2 data was saved when 92.9% of the data size was reduced due to the compression.

• Korean Journal of Agricultural and Forest Meteorology
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• v.8 no.4
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• pp.275-278
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• 2006

Google Earth enables people to easily find information linked to geographical locations. Google Earth consists of a collection of zoomable satellite images laid over a 3-D Earth model and any geographically referenced information can be uploaded to the Web and then downloaded directly into Google Earth. This can be achieved by encoding in Google's open file format, KML (Keyhole Markup Language), where it is visible as a new layer superimposed on the satellite images. We used KML to create and share fine resolution gridded temperature data projected to 3 climatological normal years between 2011-2100 to visualize the site-specific warming and the resultant earlier blooming of spring flowers over the Korean Peninsula. Gridded temperature and phonology data were initially prepared in ArcGIS GRID format and converted to image files (.png), which can be loaded as new layers on Google Earth. We used a high resolution LCD monitor with a 2,560 by 1,600 resolution driven by a dual link DVI card to facilitate visual effects during the demonstration.

• Journal of KIISE:Computer Systems and Theory
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• v.33 no.10
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• pp.734-745
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• 2006

This paper presents a PC cluster-based distributed VOD server that minimizes the load of an interconnection network by adopting the VIA communication protocol and the interval cache algorithm. Video data is distributed to the disks of the distributed VOD server and each server node receives the data through the interconnection network and sends it to clients. The load of the interconnection network increases because of the large amount of video data transferred. This paper developed a distributed VOD file system, which is based on VIA, to minimize cost using interconnection network when accessing remote disks. VIA is a user-level communication protocol removing the overhead of TCP/IP. This papers also improved the performance of the interconnection network by expanding the maximum transfer size of VIA. In addition, the interval cache reduces traffic on the interconnection network by caching, in main memory, the video data transferred from disks of remote server nodes. Experiments using the distributed VOD server of this paper showed a maximum performance improvement of 21.3% compared with a distributed VOD server without VIA and the interval cache, when used with a four-node PC cluster.

• Journal of Intelligence and Information Systems
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• v.17 no.4
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• pp.37-58
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• 2011

In general, testing DB applications is much more difficult than testing other types of software. The fact that the DB states as much as the input data influence and determine the procedures and results of program testing is one of the decisive reasons for the difficulties. In order to create and maintain proper DB states for testing, it not only takes a lot of time and efforts, but also requires extensive IT expertise and business knowledge. Despite the difficulties, there are not enough research and tools for the needed help. This article reports the result of research on automatic creation and maintenance of DB states for testing DB applications. As its core, this investigation develops an automation tool which collects relevant information from a variety of sources such as log, schema, tables and messages, combines collected information intelligently, and creates pre- and post-Images of database tables proper for application tests. The proposed procedures and tool are expected to be greatly helpful for overcoming inefficiencies and difficulties in not just unit and integration tests but including regression tests. Practically, the tool and procedures proposed in this research allows developers to improve their productivity by reducing time and effort required for creating and maintaining appropriate DB sates, and enhances the quality of DB applications since they are conducive to a wider variety of test cases and support regression tests. Academically, this research deepens our understanding and introduces new approach to testing enterprise systems by analyzing patterns of SQL usages and defining a grammar to express and process the patterns.

• Journal of Korean Library and Information Science Society
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• v.44 no.2
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• pp.217-239
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• 2013

This research was conducted to analyze the actual condition of subject heading related to Korean border shown in the subject headings of 7 countries: United States, France, Germany, Spain, Russia, China, and Japan. The results are as follows. To begin with, Korean border-related records in most other national libraries are in extremely poor conditions except for some countries like United States. Amnokgang and Dumangang-related records did not search at all in the France. Yellow Sea, Dumangang, and Baekdusan-related records did not search at all in the Spain. Second, even Dokdo we have effective control, the geographical name 'Korea' is not marked with catalog records except the United States and France. The Germany is displayed with the geographical name of 'Korea' and 'Japan'. Third, the East Sea(Donghae) already is marked with 'Sea of Japan' in most of the national library catalogs, and Yellow Sea(Huanghai) is marked with 'Yellow Sea'. Fourth, Amnokgang and Dumangang is marked with Chinese pronunciation in most in most of the national library. Fifth, Baekdusan is marked with Korean pronunciation in most countries. However the United States showed in 'Baekdu Mountain' and 'Changbai Mountain' discrimination. In the case of the Germany, 'Changbai Mountain' are marked with variant access point of 'Baekdusan'.

• Journal of Environmental Policy
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• v.7 no.1
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• pp.81-100
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• 2008

This paper reviewed the main characteristics of Web 2.0 and discussed the possible applications related to National Geographic Information Systems. In general, Web 2.0 refers to a next generation World Wide Web environment that let people participate and share information and data. The recent examples using Web 2.0 with geo-spatial information are convincing us apply Web 2.0 into National Geographic Information Systems. In order to imply Web 2.0 into National Geographic Information Systems, we should consider not only technological advancements related to providing the services but also shifting the relationship between information provider(government agencies) and end-users. In other words, new platform should be provided to users so that users can easily create, share, and mash-up data, which was previously managed and owned only by government agencies. Successful integration Web 2.0 platform into National Geographic Information Systems require some important points such that; 1) the consideration for the data should be changed from closed and agency owned data to opened and shared data. 2) data standards should be established to integrate all data from different sources. 3) real change need to be happened rather than different naming on the same system.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.25 no.3
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• pp.165-189
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• 2014

This study examined the current practices of Research Data Management (RDM) services recently built and implemented at research university libraries in the U.S. by analyzing the components of the services and the contents presented in their web sites. The study then analyzed the content of web pages describing the services provided by 31 Research Universities/Very High research activity determined based on the Carnegie Classification. The analysis was based on 9 components of the services suggested by previous studies, including (1) DMP support; (2) File organization; (3) Data description; (4) Data storage; (5) Data sharing and access; (6) Data preservation; (7) Data citation; (8) Data management training; (9) Intellectual property of data. As a result, the vast majority of the universities offered the service of DMP support. More than half of the universities provided the services for describing and preserving data, as well as data management training. Specifically, RDM services focused on offering the guidance to disciplinary metadata and repositories of relevance, or training via individual consulting services. More research and discussion is necessary to better understand an intra- or inter-institutional collaboration for implementing the services and knowledge and competency of librarians in charge of the services.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.15 no.5
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• pp.1-7
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• 2015

Recently, a coaching helps individual to lead and maximize performance. Generally there is a face to face coaching at the current spot of education, and the e-coaching is on the rise. And the face-to-face coaching means that coach and the coachee come face to face directly. And, the effective coaching method is required to supply the weakness and to maximize the strength of the e-coaching using the Internet. Accordingly, we are studying a hybrid coaching to overcome the difficulty and the limit of face-to-face coaching and online coaching. In this paper, we design and implement the career coaching system to provide the face-to-face coaching and the e-coaching for coachee based on the Web service on the Internet. We provide the hybrid coaching using Web service based on the Restful and connect with the database based on the Web to save and manage the profiles and the coaching history of the coach and the coachee. Proposed hybrid coaching system for coachee career improves remote accessibility between the coach and the coachee. This system provides the interaction without the limit of the time and the space, and overcomes the limit of the traditional face-to-face coaching on the online environment.

• Journal of Internet Computing and Services
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• v.21 no.2
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• pp.39-48
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• 2020

Data mining techniques have been suggested to find efficiently meaningful and useful information. Especially, in the big data environments, as data becomes accumulated in several applications, related pattern mining methods have been proposed. Recently, instead of analyzing not only static data stored already in files or databases, mining dynamic data incrementally generated in a real time is considered as more interesting research areas because these dynamic data can be only one time read. With this reason, researches of how these dynamic data are mined efficiently have been studied. Moreover, approaches of mining representative patterns such as maximal pattern mining have been proposed since a huge number of result patterns as mining results are generated. As another issue, to discover more meaningful patterns in real world, weights of items in weighted pattern mining have been used, In real situation, profits, costs, and so on of items can be utilized as weights. In this paper, we analyzed weighted maximal pattern mining approaches for data generated incrementally. Maximal representative pattern mining techniques, and incremental pattern mining methods. And then, the application scenarios for analyzing the required commodity patterns in infants are presented by applying weighting representative pattern mining. Furthermore, the performance of state-of-the-art algorithms have been evaluated. As a result, we show that incremental weighted maximal pattern mining technique has better performance than incremental weighted pattern mining and weighted maximal pattern mining.