• Journal of Information Technology and Architecture
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• v.10 no.1
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• pp.123-135
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• 2013

This paper presents a two-dimensional grouping index(2DG-index) for efficient processing of XML filtering queries. Recently, many index techniques have been suggested for the efficient processing of structural relationships among the elements in the XML database such as an ancestor- descendant and a parent-child relationship. However, these index techniques focus on simple path queries, and don't consider the path queries that include a condition value for filtering. The 2DG-index is an index structure that deals with the problem of clustering index entries in the twodimensional domain space that consists of a XML path identifier domain and a filtering data value domain. For performance evaluation, we have compared our proposed 2DG-index with the conventional one dimensional index structure such as the data grouping index (DG-index) and the path grouping index (PG-index). As the result of the performance evaluations, we have verified that our proposed 2DG-index can efficiently support the query processing in XML databases according to the query types.

• Journal of the Korean Society for information Management
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• v.33 no.3
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• pp.7-29
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• 2016

The h-index is a popular bibliometric indicator for evaluating individual researchers. However, it has been criticized for its inconsistency with reflecting increased number of citations and disregarding the number of co-authors in a paper. In order to overcome these problems, we examined the g-index and other Hirsch-type indices considering the number of co-authors. Test data collection was extracted from Korean Citation Index database published from 2004 to 2013. The results of this study are as follows: First, g-index is more reliable indicator than h-index with consistency. Second, number of co-authors must be considered to maintain the h-index as an complex indicator applying the quality and the quantity of research performance. Finally, hc-index and gc-index, with fractionalised counting of the papers, can fairly measure the research performance of humanities researchers, and successfully prevent specific disciplines or institutions occupying majority of top rankings.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2014.05a
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• pp.622-625
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• 2014

As Big data began to produce a variety of values, a database that allows for huge amount of data with varieties became to be needed. Therefore, for the purpose of overcoming the limitations of the complexity and capacity of the existing RDBMS, NoSQL databases were introduced. Among the different types of NoSQL databases, MongoDB is most commonly used and is offered as open sources. The B-Tree index, used in MongoDB, experiences a significant decrease in performance as the amount of data increases. The fractal tree index enables to enhance the performance of B-Tree substantially by improving B-Tree's insertion algorithm. In this paper, the performances of MongoDB when using B-Tree Index and when using Fractal Tree Index are compared.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2002.11a
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• pp.281-285
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• 2002

Although DC ground resistance is a good index of performance for a grounding system, it does not reflect the grounding performance during the transient states. Besides, impulse ground impedance, which is defined by a ratio of the peak value of transient ground potential rise to the peak value of impulse current, cannot be an absolute performance index due to its dependence on impulse current shape. In this paper, a grounding performance of needle-typed ground rod has been compared with simple ground rod using HIFREQ[1], which is an engineering electro-magnetic code based on MoM (Method of Moment).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.12
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• pp.744-754
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• 2017

In this study, an analytic hierarchy process (AHP) was conducted with the aim of developing a post-disaster refugee housing performance index system (PPS) to improve the post-disaster refugee housing (PRH) performance criteria for the foundation of quality-based development. The PRH was defined as a mid-term temporary housing facility that is used for a certain period before the permanent housing is established. The safety, rapidity, reusability, habitability, and economy were derived from major performance factors through prior research. A hierarchical PPS was organized by linking the major performance factors with the whole life cycle process of PRH. The priority of each performance index of PPS was determined quantitatively using the analytic hierarchy process through an expert survey. Based on AHP analysis, the performance criterion of the total weight 1-10 ranking and the performance criterion of the first rank in each category were classified into the essential performance criterion (must be achieved) and the others were classified into the recommended performance criterion (optional achieved) and the performance index was constructed considering all stages of PRH development. With the completion of the PRH performance index, it is expected that victims will be able to secure stable residence and return to their daily lives quickly.

• Journal of Korean Library and Information Science Society
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• v.47 no.2
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• pp.287-304
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• 2016

This paper introduces a new bibliometric measure called Quality Factor, which assesses multiple facets of faculty research performance. The computation of Quality factor is based on a combination of publication count, citation count, h-index, and Impact Factor. In order to analyze the relationship between Quality Factor and other bibliometric measures (publication count, citation count, h-index, g-index, Impact Factor), the study collected publication data of 189 Korean Library and Information Science professors from 2001 to 2014 to produce the rankings of the faculty by each bibliometric measure and computed Spearman's rank correlations between the rankings. The overall results showed Quality Factor to be correlated to citation-driven measures (citation count, h-index, g-index), but the scatterplot as well as rank-interval analysis showed Quality Factor to be distinctive and more discriminating than other measures.

• Journal of Advanced Navigation Technology
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• v.22 no.5
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• pp.375-383
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• 2018

In order to apply the Network RTK (real time kinematics) technology, which has been used for positioning of stationary points, to the navigation of vehicles, its infrastructure should provide correction data with a quality indicator that can show the expected accuracy in real time. In this paper, we analyzed various indicator generation algorithms such as I95 (ionospheric index 95) / G95 (geodetic index 95), SBI (semivariance based index) and RIU (residual interpolation uncertainty). We also applied them to the raw observables from the reference stations of National Geographic Information Institute and VRS (virtual reference station) users, and then examined its feasibility to be used as a real-time performance index of the Network RTK rover. 24 hour data analysis shows that the RIU index, which can represent the non-linearty of the correction, has the strongest correlation with the Network RTK rover accuracy. Therefore, RIU index is expected to be used as a real-time performance index of the Network RTK rover.

• International Area Studies Review
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• v.13 no.1
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• pp.39-51
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• 2009

The misery index is the sum of the inflation rate and the unemployment rate. The higher the index, the lower the performance of the national economy. Lee and Cheong (2007) propose that the open misery index, defined to be the sum of the misery index and the ratio of current account to GDP, properly measure the economic performance of a national economy when its degree of openness is large. This paper shows that the periods of rising open misery index of the USA coincide with those of economic hardship in the USA. Most recently, the open misery index of the USA has shown a rising trend for a decade prior to the current economic crisis. That is, external and internal imbalances of the USA have accumulated for a decade prior to the current economic crisis. We interpret the recent rising trend of the open misery index of the USA as a precursor of the current economic crisis.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1024-1027
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• 2005

This paper describes the performance index of mobile robot and development of testbed which is used to evaluate the index. The developed testbed has rectangular structure similar to a living room of home. It is semi-automation testbed system for evaluation of cleaning performance index. This system is composed with scattering and cleaning equipment of test materials, equipment rifting of objects in inner space and sides itself, vision processing system. To be consistent of performance evaluation of cleaning robot, we make use of camera in this system for the sake of measurement of robot s mobility, path and suction quantity.

• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.2
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• pp.49-57
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• 2008

The performance of crash cushion systems is certified through the full scale crash tests by the standard for installation and maintenance guidelines for roadside safety appurtenance. The impact severities of impacting vehicles in collision with crash cushion systems are rated by indices THIV and PHD. Crash test results are considered to study the performance of three crash cushion systems. In case of the frontal impact or the offset frontal impact, the results show that THIV values of three systems are very close to the threshold limit for the occupant protection. Also, the results show that PHD would be improper for the occupant protection performance index. In order to improve the occupant protection performance of crash cushions, ASI needs to be included in the impact severity index.