• Proceedings of the KAIS Fall Conference
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• 2003.11a
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• pp.191-194
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• 2003

Product factory is a real-time financial product design system for the Internet customers. Recently, as the number of the Internet customers increases, the importance of the product factory becomes more emphasized. However, there is not much research performed regarding its definition, properties, requirements, nor implementation. In this research, we make a clear definition of product factory, and analyze the requirements of the system from the perspectives of functions and services, and we propose an architecture that reflects the analyzed requirements. In additions, we implemented a prototypical system based on the proposed architecture to prove the usefulness of this research.

• Journal of the military operations research society of Korea
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• v.16 no.1
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• pp.113-129
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• 1990

This paper presents the simulation model to decide the mean size of cannibalization aircraft (MSCA) under steady state when an airbase makes use of cannibalization to support the spare parts of an airfleet. In this model, the essential factors such as mission requirements, mission time, failure time, repair time, repair capability, inventory policy, cannivalization rule are considered. The model is constructed with above factors and actual airbase operating rules for a basis. Because of the tangled interdependencies among the each factors, it is inevitable to construct the model by the simulation technique. The mission and support system of the airbase is considered as a closed queueing network with a finite number of unit The troubled aircrafts are repaired in accordance with the priorities that are determined by their repair times. The illustrative example of the model, using the actual data of xx-airbase, is presented. The model would be a useful tool not only to determine the MSCA and the size of scheduled maintenance aircraft but to evaluate the NORS (not operationally ready supply) rate and the availability of an airfleet.

• Nuclear Engineering and Technology
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• v.53 no.3
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• pp.866-878
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• 2021

Procedures play a key role in ensuring safe operation at nuclear power plants (NPPs). Development and maintenance of a large number of procedures reflecting the best knowledge available in all relevant areas is a complex job. This paper introduces a newly developed methodology and the implemented software, called iExtractor, for the extraction of syntactic and semantic information from NPP procedures utilizing natural language processing (NLP)-based technologies. The steps of the iExtractor integrated with sets of rules and an ontology for NPPs are described in detail with examples. Case study results of the iExtractor applied to selected procedures of a U.S. commercial NPP are also introduced. It is shown that the iExtractor can provide overall comprehension of the analyzed procedures and indicate parts of procedures that need improvement. The rich information extracted from procedures could be further utilized as a basis for their enhanced management.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.34 no.6
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• pp.619-627
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• 2016

Cells of a PV (photovoltaic) module can suffer defects due to various causes resulting in a loss of power output. As a malfunctioning cell has a higher temperature than adjacent normal cells, it can be easily detected with a thermal infrared sensor. A conventional method of PV cell inspection is to use a hand-held infrared sensor for visual inspection. The main disadvantages of this method, when applied to a large-scale PV power plant, are that it is time-consuming and costly. This paper presents an algorithm for automatically detecting defective PV panels using images captured with a thermal imaging camera from an UAV (unmanned aerial vehicle). The proposed algorithm uses statistical analysis of thermal intensity (surface temperature) characteristics of each PV module to verify the mean intensity and standard deviation of each panel as parameters for fault diagnosis. One of the characteristics of thermal infrared imaging is that the larger the distance between sensor and target, the lower the measured temperature of the object. Consequently, a global detection rule using the mean intensity of all panels in the fault detection algorithm is not applicable. Therefore, a local detection rule was applied to automatically detect defective panels using the mean intensity and standard deviation range of each panel by array. The performance of the proposed algorithm was tested on three sample images; this verified a detection accuracy of defective panels of 97% or higher. In addition, as the proposed algorithm can adjust the range of threshold values for judging malfunction at the array level, the local detection rule is considered better suited for highly sensitive fault detection compared to a global detection rule. In this study, we used a panel area extraction method that we previously developed; fault detection accuracy would be improved if panel area extraction from images was more precise. Furthermore, the proposed algorithm contributes to the development of a maintenance and repair system for large-scale PV power plants, in combination with a geo-referencing algorithm for accurate determination of panel locations using sensor-based orientation parameters and photogrammetry from ground control points.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.39 no.4
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• pp.38-49
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• 2021

The maintenance project of the Jeonglimsa temple site started with the objective of restoring the original structure of the temple, however, it was gradually transitioned to a landscaping maintenance project over time that constructs a landscape of the temple area. With paying attention to these facts, this study summarized the characteristics of cultural heritage landscaping of the Jeonglimsa temple site as follows. First, Cultural heritage landscaping is a landscaping act that creates, maintains, and manages landscapes within the spatial scope of the cultural heritage designated under the Cultural Heritage Protection Act and the cultural heritage protection area established around it. It is a work that includes protection and maintenance of the excavated remains, spaces by each function and plans for moving lines, Installation of structures to protect cultural properties, adoption of the facilities and structures for convenience of visitors, and construction of vegetation landscape. Second, the cultural heritage landscaping of the Jeonglimsa temple site has been developed in 5 periods, and these include 'the period of historical site investigation' that the temple name was identified through the designation of cultural assets and excavation investigation by the Japanese rule, 'the construction period of Baekje Tower Park' after the liberation from the Japanese rule, 'the period of Baekje Cultural Area Development Project' designated as a historical site, 'the period of the Comprehensive Development Project for a Specific Area of Baekje Culture',which was proceeded with the establishment of the park and museum instead of restoring the temple building due to the difficulty in gathering the pieces of historical evidence, and 'the period of the Jeonglimsa temple site restoring project', which was designated as a World Heritage Site while restoring the buildings deployment in the Buddhist temple at the time of foundation era of Baekje Dynasty. Third, this study verified the landscape changes of the Jeonglimsa temple site that have been transitioned, for instance, the creation of a commemorative park linked to the outer garden of Buyeo Shrine, the implementation of urban planning of the Japanese colonial era, the creation of a protective environment for the excavated historical structures and temple area, the restoration of building deployment in the Buddhist temple, and the sincerity restoration and utilization of cultural assets. Fourth, the landscape of Jeongnimsa temple site is determined by the subject and scope of cultural property designation, land use, movement lines and pavement, repairing methods of remains, structures, facilities, and vegetation. The characteristics of the cultural heritage landscape of Jeongnimsa Temple were derived, such as creating a procedural landscape considering the expansion of the cultural heritage designation scope, securing authenticity by maintaining relics in consideration of reversibility, creating a vegetative landscape suitable for historical and cultural landscapes, and enhancing the value of cultural heritage enjoyment by providing an open space.

• The KIPS Transactions:PartB
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• v.12B no.4 s.100
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• pp.479-486
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• 2005

The ontology was proposed to construct the logical basis of semantic web. Ontology represents domain knowledge in the formal form and it enables that machine understand domain knowledge and provide appropriate intelligent service for user request. However, the construction and the maintenance of ontology requires large amount of cost and human efforts. This paper proposes an automatic ontology construction method for defining relation between concepts in the documents. The Proposed method works as following steps. First we find concept pairs which compose association rule based on the concepts in domain specific documents. Next, we find pattern that describes the relation between concepts by clustering the context between two concepts composing association rule. Last, find generalized pattern name by clustering the clustered patterns. To verify the proposed method, we extract relation between concepts and evaluate the result using documents set provide by TREC(Text Retrieval Conference). The result shows that proposed method cant provide useful information that describes relation between concepts.

• Journal of Preventive Medicine and Public Health
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• v.54 no.4
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• pp.230-237
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• 2021

Objectives: This study explored changes in individuals' behavior in response to social distancing (SD) levels and the "no gatherings of more than 5 people" (NGM5) rule in Korea during the coronavirus disease 2019 (COVID-19) pandemic. Methods: Using survey data from the COVID-19 Behavior Tracker, exploratory factor analysis extracted 3 preventive factors: maintenance of personal hygiene, avoiding going out, and avoiding meeting people. Each factor was used as a dependent variable. The chisquare test was used to compare differences in distributions between categorical variables, while binary logistic regression was performed to identify factors associated with high compliance with measures to prevent transmission. Results: In men, all 3 factors were significantly associated with lower compliance. Younger age groups were associated with lower compliance with maintenance of personal hygiene and avoiding meeting people. Employment status was significantly associated with avoiding going out and avoiding meeting people. Residence in the capital area was significantly associated with higher compliance with personal hygiene and avoiding venturing out. Increasing SD levels were associated with personal hygiene, avoiding going out, and avoiding meeting people. The NGM5 policy was not significantly associated with compliance. Conclusions: SD levels, gender, age, employment status, and region had explanatory power for compliance with non-pharmaceutical interventions (NPIs). Strengthening social campaigns to inspire voluntary compliance with NPIs, especially focused on men, younger people, full-time workers, and residents of the capital area is recommended. Simultaneously, efforts need to be made to segment SD measures into substrategies with detailed guidance at each level.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.1222-1229
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• 2011

Railway bridges are divided into ballastless and ballast track bridges. The ballast abrasion occurs on the ballast track upon bridges more than soil roadbed because the track vibration occurs a lot in the ballast track upon bridges due to girder vibration when a train's weight is loaded onto track even though the identical ballast is used. The phenomena of mud pumping especially, which occurs when drainage is not properly secured for heavy rain, leads to the increase of maintenance work load and the decline of ride comfort. There are countermeasures such as ballast change, installation of cross-drainage for poor drainage, gutter establishment, ballast lifting methods, ballast mats and resilient sleepers laying for the mud pumping. The ballast thickness range in domestic railroad construction rule is uniformly set up according to the design speed of railroad and passing tonnage of train without considering field conditions which is considered in foreign railroad companies. The purpose of this study is to verify the effect of vibration decrease by measuring the acceleration, displacement and ride comfort of ballast track with the change of ballast thickness on the ballast track bridges and to suggest the optimal height of ballast on the Yocheon Bridge built for the test in Honam Line.

• Structural Engineering and Mechanics
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• v.49 no.2
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• pp.203-223
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• 2014

The extensive use of prestressed reinforced concrete (PSC) highway bridges in marine environment drastically increases the sensitivity to both fatigue-and corrosion-induced damage of their critical structural components during their service lives. Within this scenario, an integrated method that is capable of evaluating the fatigue reliability, identifying a condition-based maintenance, and predicting the remaining service life of its critical components is therefore needed. To accomplish this goal, a procedure for fatigue reliability prediction of PSC highway bridges is proposed in the present study. Vehicle-bridge coupling vibration analysis is performed for obtaining the equivalent moment ranges of critical section of bridges under typical fatigue truck models. Three-dimensional nonlinear mathematical models of fatigue trucks are simplified as an eleven-degree-of-freedom system. Road surface roughness is simulated as zero-mean stationary Gaussian random processes using the trigonometric series method. The time-dependent stress-concentration factors of reinforcing bars and prestressing tendons are accounted for more accurate stress ranges determination. The limit state functions are constructed according to the Miner's linear damage rule, the time-dependent S-N curves of prestressing tendons and the site-specific stress cycle prediction. The effectiveness of the methodology framework is demonstrated to a T-type simple supported multi-girder bridge for fatigue reliability evaluation.

• Spatial Information Research
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• v.10 no.3
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• pp.421-438
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• 2002

Abstraction of geographic data within a spatial database context must deal with geometrical simplification, modification or maintenance of the integrity of features, spatial and aspatial data, topology within class, and relationships between classes. This research is to propose a method to abstract a spatial database into a high level database. This study refines operators to carry out the modifications required by the abstraction process in the spatial database. Then, a set of operator sequences (workflows) is suggested to specify operators required to abstract a given feature class and to arrange them in order. Finally, a prototype system is developed, based on rule management with a graphic user interface. When the abstraction process is implemented sequentially we demonstrate that a preferential ordering of operations improves efficiency and reduces loss and distortion in the information.