• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.11a
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• pp.319-324
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• 2004

With a PMS, a maintenance plan should be drawn up after surface conditions are precisely examined and analyzed. The majority of the present PMSs are run by the fact that experts first examine surface conditions on sites, and then enter results into systems. However, considering the actual circumstances of the present time and an increase in paved road hereafter, it is inefficient that experts examine the whole paved roads in person and long-lasting PMSs can not be kept up. Therefore, in the study digital photogrammetry was used to examine asphalt concrete pavements. In a consequence, it was found that if databases are implemented in the future with quality digital image information accumulated from studies on roads, they will be able to provide the field of pavement management system with a large amount of information and data.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.7 no.3
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• pp.30-39
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• 2011

URANUS (Ubiquitous, Robust, Accident-forgiving, Non-proliferating, Ultra-lasting and Sustainer) has been developed with 35MWe (100MWth) operating without primary coolant pump, capitalizing on natural circulation capability of lead-bismuth eutectic (LBE) for long-life small and robust power units. To ensure the structural integrity, the large safety margin against Safe Shutdown Earthquake, 0.3g, and furthermore the cost effectiveness for URANUS, three-dimensional seismic base isolation design has been developed. The analytical model has been developed and seismic time history analyses have been carried out. The advantage for using three-dimensional seismic base isolation for URANUS has been discussed.

• Proceedings of the KSR Conference
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• 2005.11a
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• pp.836-841
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• 2005

As gravel roadbed is gradually turn down by repetitive loading of train, lasting work for maintenance and management of track is necessary to reduce the settlement of roadbed and the deterioration of track. Despite of above weak point, gravel roadbed has become a basic structure of roadbed at the present time. But request for new structure of roadbed is recently presented to settle an increased transportation capacity of track, and to solve a shortage of the labor to handle maintenance work of track. Therefore, we begin to research about maintenance-free roadbed like paved track from two years ago. In this study, a series of tests were performed to clarify the characteristics of strength and permeability of concrete specimen, which is the upper part of paved track injected by cement mortar, by type of geotextile and finally to give a basic data for application of geotextile to the lower part of paved track.

• Journal of Communications and Networks
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• v.8 no.3
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• pp.339-350
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• 2006

Several novel concepts and tools have revolutionized our understanding of the Internet topology. Most of the existing efforts attempt to develop accurate analytical models. In this paper, our goal is to develop an effective conceptual model: A model that can be easily drawn by hand, while at the same time, it captures significant macroscopic properties. We build the foundation for our model with two thrusts: a) We identify new topological properties and b) we provide metrics to quantify the topological importance of a node. We propose the jellyfish as a model for the inter-domain Internet topology. We show that our model captures and represents the most significant topological properties. Furthermore, we observe that the jellyfish has lasting value: It describes the topology for more than six years.

• Korean Institute of Interior Design Journal
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• no.8
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• pp.16-22
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• 1996

In terms of modern design history, De Stijl movement had continued as one of influential groups by 1931, and it attempted to pursue universial reality that combined painting and architecture, seeking a new style based on Neo-Plasticism and succeeded the nineteen century's Art and Craft movement and Art Nouveau. Especially, the De Stijl movement provided 1920's rationalism with new space pattern and its ideas greatly affected the Bauhaus movement such as Walter Gropius or Mies van der Rohe. De Stijl's utopian idea that claimed on the conformity of art and life contributed modernism movement combined with scientific and rational view, and even now experts its lasting power with the concept of time and space free from simple cube in modern architecture and interior design. The tue meaning of the De Stijl movements is that is sis the basis of general ideas, and the change of modern architecture is based on this modern styled foundation. It may be the unchangeable fact like Russell Hitchocok says, "The architectural style and pattern which everyone admitts its importance has the value of living."

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.55 no.11
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• pp.468-475
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• 2006

This paper reviews the energy characteristics of oil filled cables in transient state such as grounding fault and lightning surge. Artificial grounding fault test was firstly performed in 2003 for the analysis of arc voltage and breakdown energy according to the fault current. In this paper, energy of OF cable is variously analysed at joint box based on the actual test. Then more various conditions such as installation types, section lengths and CCPU(Cable Covering Protection Unit) connection types are applied for the simulation using EMTP when the single line to ground fault and direct lightning stroke are occurred on actual underground power cable systems and combined power cable systems, respectively. Finally, the energy by the length of crossbonded lead and grounding lead as well as fault lasting time is also calculated using EMTP simulation.

• Bulletin of the Korean Chemical Society
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• v.18 no.4
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• pp.379-384
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• 1997

High quality MCM-41 is prepared from a gel of molar composition SiO2:0.20 CTACl:0.18 TMAOH:25 H2O aged at 20 ℃ for 24 hours before crystallization lasting for 48 hours. The (110) and (200) peaks of XRD pattern of high quality MCM-41 are unusually well resolved and the FWHM (full-width-at-half-maximum) of the (100) peak is 0.13° for as-prepared MCM-41 and 0.21° for calcined one, which indicate well-developed crystals. The properties of the crystal depend on the source and concentration of the reactants and the gel aging time. There is no induction period in the course of the synthesis, which is conveniently monitored by pH measurement. Gel aging, during which a spatial distribution of silicate polyanions and micellar cations is established, is essential for preparing high quality MCM-41. Surfactants with the same cationic organic group but different counteranions change the crystallization behavior. Highly basic gel (pH=12.6) favours the lamellar product; the quality of MCM-41 is lower as insufficient TMAOH is available to dissolve the silica.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.4
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• pp.1825-1844
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• 2019

Political campaigns circulate manipulative opinions in online communities to implant false beliefs and eventually win elections. Not only is this type of manipulation unfair, it also has long-lasting negative impacts on people's lives. Existing tools detect political manipulation based on a supervised classifier, which is accurate when trained with large labeled data. However, preparing this data becomes an excessive burden and must be repeated often to reflect changing manipulation tactics. We propose a practical detection system that requires moderate groundwork to achieve a sufficient level of accuracy. The proposed system groups opinions with similar properties into clusters, and then labels a few opinions from each cluster to build a classifier. It also models each opinion with features deduced from raw data with no additional processing. To validate the system, we collected over a million opinions during three nation-wide campaigns in South Korea. The system reduced groundwork from 200K to nearly 200 labeling tasks, and correctly identified over 90% of manipulative opinions. The system also effectively identified transitions in manipulative tactics over time. We suggest that online communities perform periodic audits using the proposed system to highlight manipulative opinions and emerging tactics.

• International Journal of High-Rise Buildings
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• v.10 no.1
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• pp.45-54
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• 2021

The adaptive reuse of 20th-century high-rise architecture poses important questions about the prevalence of authorized discourses in the heritage conservation field. Based on a two-year teaching experience at Tongji University about the adaptive reuse of the Metropolo Hotel (Palmer and Turner, 1934), an iconic historic high-rise building in the Shanghai Bund area, this paper will show the extent to which disciplinary and urban authorized heritage discourses are present in the development of design and representation strategies in adaptive reuse. Using discourse analysis as a method, this paper will make the argument that disciplinary discourses have a limited effect in the practice of adaptive reuse, which is perceived as a fundamentally creative activity. At the same time, the paper reveals how urban discourses have a much more lasting effect, confirming the intimate links between adaptive reuse and the wider phenomena of beautification and gentrification of high-rise listed areas.

• BMB Reports
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• v.56 no.9
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• pp.469-481
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• 2023

The gut microbiome is widely recognized as a dynamic organ with a profound influence on human physiology and pathology. Extensive epidemiological and longitudinal cohort studies have provided compelling evidence that disruptions in the early-life microbiome can have long-lasting health implications. Various factors before, during, and after birth contribute to shaping the composition and function of the neonatal and infant microbiome. While these alterations can be partially restored over time, metabolic phenotypes may persist, necessitating research to identify the critical period for early intervention to achieve phenotypic recovery beyond microbiome composition. In this review, we provide current understanding of changes in the gut microbiota throughout life and the various factors affecting these changes. Specifically, we highlight the profound impact of early-life gut microbiota disruption on the development of diseases later in life and discuss perspectives on efforts to recover from such disruptions.