• Structural Engineering and Mechanics
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• v.51 no.6
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• pp.1037-1046
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• 2014

Most existing damage detection methods based on curvature should investigate the indicator value changes between the intact and damaged state. However, the 'footprint' in the intact state is usually not available for most actual beams. Therefore, a new damage localization indicator called Difference of Nearby Difference Curvature Indicator (DNDCI) was introduced for single-span beams. This indicator does not require prior information of the intact beam and is sensitive to the damage occurs on or nearby the measuring points. Practical and detailed application method of DNDCI has been proposed. Besides the idealized simply supported beams, it was validated by example that DNDCI is also applicable to the actual single-span beams supported by bearings.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.7
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• pp.1141-1149
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• 2008

Most faults are single-phase-to-ground fault in ungrounded system. The fault currents of single-phase-to-ground are much smaller than detection thresholds of measurement devices, so detecting single-phase-to-ground faults is difficult and important in ungrounded system. This paper proposed to a FI(Fault Indicator) generation algorithm in ungrounded system. The algorithm just using line-to-line voltage and zero-sequence current detects fault line, fault phase, fault section and FI(Fault Indicator) at terminal device, This paper also proposed to application plan for this algorithm. In the case study, the proposed algorithm has been testified in demo system by Matlab/Simulink simulations.

• Structural Engineering and Mechanics
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• v.53 no.4
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• pp.725-744
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• 2015

In this paper, a new damage indicator based on mode shape data is introduced to identify damage in beam structures. In order to construct the indicator proposed, the mode shape, mode shape slope and mode shape curvature of a beam before and after damage are utilized. Mode shape data of the beam are first obtained here using a finite element modeling and then the slope and curvature of mode shape are evaluated via the central finite difference method. In order to assess the robustness of the proposed indicator, two test examples including a simply supported beam and a two-span beam are considered. Numerical results demonstrate that using the proposed indicator, the location of single and multiple damage cases having different characteristics can be accurately determined. Moreover, the indicator shows a better performance when compared with a well-known indicator found in the literature.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.11a
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• pp.224-226
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• 2003

In this paper, we succeeded SNP discrimination of DNA hybridization on microarray using new electrochemical system. Using the electrochemical method with a label-free DNA has Performed DNA chip microarray. This method is based on redox of an electrochemical ligand. We developed scanning system with high performance.

• Korean Journal of Veterinary Research
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• v.40 no.1
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• pp.49-55
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• 2000

Lysogenic conversion of Staphylococcus aureus to loss of ${\beta}-hemolysin$ production by serological group F phages is always associated with gain in staphylokinase production. In this study, the new phages belonging to serotype F were detected during the course of isolation of phages from Staph aureus of bovine origin and some characteristics of the new phages isolated were investigated. The new phages, ${\phi}470$ and ${\phi}499$, isolated from Staph aureus producing ${\beta}-hemolysin$ and staphylokinase(${\beta}^+\;K^+$) were found to convert ${\beta}^+\;K^+$ strain to ${\beta}^+K\;^+$, Staph aureus strains lysogenized by this serotype F single-converting phage ${\phi}470$ or ${\phi}499$ could be again lysogenized with serotype F double-converting phage ${\phi}506$. The frequency of lysogenization of indicator strains by serotype F single-converting phage was 100%, whereas the frequency for serotype F double-converting phage ${\phi}506$ varied from 4.2% to 97.6% according to the indicator strains. The indicator strain lysogenized with phage ${\phi}470$ was resistant to phage ${\phi}499$, and vice versa, but not to phage ${\phi}506$. Therefore, phage ${\phi}470$ and ${\phi}499$ were shown to be identical by immunity test.

• Structural Engineering and Mechanics
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• v.60 no.6
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• pp.1093-1117
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• 2016

Global sensitivity analysis (GSA) has been widely used to investigate the sensitivity of the model output with respect to its input parameters. In this paper a new single-solution search optimization algorithm is developed based on the GSA, and applied to the size optimization of truss structures. In this method the search space of the optimization is determined using the sensitivity indicator of variables. Unlike the common meta-heuristic algorithms, where all the variables are simultaneously changed in the optimization process, in this approach the sensitive variables of solution are iteratively changed more rapidly than the less sensitive ones in the search space. Comparisons of the present results with those of some previous population-based meta-heuristic algorithms demonstrate its capability, especially for decreasing the number of fitness functions evaluations, in solving the presented benchmark problems.

• Journal of the Korea Furniture Society
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• v.27 no.3
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• pp.226-236
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• 2016

Single-person household is estimated to be about 26.5% of the total household in 2015, which counts as 5060000 in numbers. We opt to acknowledge the various requests of these single residents, and in order to raise their satisfaction, we investigated on how personal taste, psychological interest, and personality attribute affects the user's preference of space organization and furniture in one room housing. Using the qualified psychology program, Enneagram Personality Type Indicator, we surveyed young people under 30 years old (majority of single-person households), regarding space organization and furniture preference. With the help of a specialist, the survey was constructed with appropriate evaluation items (space organization in one room households, bed, sofa, furniture material, etc), and analyzed the relationship between the evaluated items and personality types. Results showed there is a relationship between personality types and spatial structure. First, preference of spatial structure differed for different personality types. Second, the shape and size of furniture was dependent more on the ease of usability and design rather than on the personality types. One thing to consider is that type 1 and 9 accounted for about 50% of the total surveys. This emphasizes that the preferred spatial structure of a dominant specific personality type should not be overlooked.

• Journal of the Korean Society for information Management
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• v.32 no.4
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• pp.205-221
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• 2015

The impact of a journal is commonly used as the impact of an individual paper within that journal. It is problematic to interpret a journal's impact as a single paper's impact of the journal, so there are several researches to measure a single paper's impact with its own citation counts. This study applied 8 impact indicators to Korean Citation Index database and examined discipline bias of each indicator. Analyzed indicators are simple citation counts, PageRank, f-value, CCI, c-index, single publication h-index, single publication hs-index, and cl-index. PageRank has the least discipline bias at highly ranked papers and journal bias in a discipline. On the contrary, simple citation counts showed strongly biased results toward a certain discipline or a journal. KCI database provides only simple citation counts. It needs to show PageRank (global indicator) to discover influential papers in diverse areas. Furthermore it needs to consider to provide the best of local indicators. Local indicators can be calculated only with papers in users' search results because they uses citation counts of citing papers and the number of references. They are more efficient than global indicators which explore the whole database. KCI should also consider to provide Cl-index (local indicator).

• Journal of the Korean Society for Aviation and Aeronautics
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• v.31 no.3
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• pp.103-118
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• 2023

An indicator system is an effective way to monitor ongoing safety status. Current aviation safety measurements account for many qualitative technical and lagging indicators. Conversely, quantitative and leading indicators have only a tiny proportion. This research added more quantitative leading indicators and reviewed them to harmonize lagging and leading indicators to measure airport safety and provide an index. The South Korean national gate, Incheon International Airport's indicators, were applied as primary data to verify this research practically. Then, examples from International and national authorities were reviewed and extracted for use. Fifty-five safety specialists participated in the focus group discussion and three rounds of the Delphi survey. Finally, 51 sub-indicators were newly chosen. After this process, weights for each indicator could be assigned using the AHP (Analytical Hierarchy Process) to provide an integrated index. The result of the simulation with newly added indicators in the past five years (2020-2022) reliable trend showed in indicators and integrated index. Moreover, this allows monitoring the status of the details of indicators and holistic insight. This study considered that it is more suitable for a single company or service provider to use it according to the exact situation than in a macro- and general-purpose at the country or regional level.

• Journal of Environmental Science International
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• v.22 no.7
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• pp.863-871
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• 2013

Dielectric discharges are an emerging technique in environmental pollutant degradation, which that are characterized by the production of hydroxyl radicals as the primary degradation species. For practical application of the plasma reactor, reactor that can handle large amounts of water are needed. Plasma research to date has focused on small-scale water treatment. This study was carried out basic study for scale-up of a single DBD (dielectric barrier discharge) plasma reactor. The degradation of N, N-Dimethyl-4-nitrosoaniline (RNO, indicator of the generation of OH radical) was used as a performance indicator of multi-plasma reactor. The experiments is divided into two parts: design parameters [effect of distance of single plasma module (1~14 cm), arrangement of ground electrode (single and multi), rector number (1~5) and power number (1~5)]; operation parameter [effect of applied voltage (60~220 V), air flow rate (1~5 L/min), electric conductivity of solution ($1.4{\mu}S/cm$, deionized water)~18.8 mS/cm (addition of NaCl 10 g/L) and pH (5~9)]. Considering the electric stability of the plasma reactor, optimum spacing between the single plasma module was 2 cm. Multi discharge electrodes - single ground electrode array was selected. Combination of power 3-plasma module 5 was the optimal combination for maximum RNO degradation. The optimum 1st voltage and air flow rate for RNO degradation were 180 V and 4 L/min, respectively. The pH and conductivity of the solution was not influencing the RNO degradation.