• Conservation Science in Museum
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• v.25
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• pp.9-26
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• 2021

This paper describes the production methods that were originally used for an arrow bundle excavated from a Bronze Age residential area in Auraji in Jeongseon, Gangwon-do Province and the conservation treatment process that it subsequently underwent. An arrow conventionally consists of an arrowhead and a shaft. It is rare to excavate a shaft along with an arrowhead in a complete form since the shaft is made of organic materials. Notably, the arrow bundle from the Auraji site is of great significance as it shows traces of tangless stone arrowheads attached to charred shafts and offers an important case of the split end of a piece of a tree being inserted into an arrowhead. For a further examination of the characteristics of the arrows from Auraji, microscopic investigation was conducted and the type of wood used for the arrow shafts was examined. The sequence and direction of processing and the particle sizes of the grinding tools were revealed through the analysis of traces of grinding on the stone arrowheads. The shaft is presumed to have been made from a green length of three-year-old willow (Salix spp.). A curing agent with a high degree of waterproofing and reversibility was used during the on-site curing process according to demands of the surrounding environment, and a technique that the authors call the "Bridge" method was used for emergency collection of the relics. Once the bundle was transferred to the conservation treatment lab, reinforcing materials were carefully chosen as it was important not to damage the relics during the process of turning them for the repair of their reverse sides. For this purpose, artificial clay was selected since it can safely bear a load and has excellent physical properties. Finally, detached parts were rejoined, the relics and their surrounding materials were cleaned, and the bottom sides were finished with epoxy resin prior to the display of the relics at the museum.

• Korean Journal of Ecology and Environment
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• v.38 no.2 s.112
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• pp.181-187
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• 2005

For 4 years (2000 ${\sim}$ 2003), annual fluctuations of standing crops of cyanobacteria and physicochemical factors were examined at five sites from Bridge of Seungsoo to Bridge of Seungsan in the lower part of Han River. The cyanobacterial abundance (ND to 4,167 cells $mL^{-1}$) was strongly decreased during the heavy rains in every year. During the similar periods in 2003, cyanobacteria hardly observed, and comprised below of 10 percentage of total phytoplankton. In the period of little cyanobacteria, some green algae and diatom dominated the phytoplankton community, while the concentration of chlorophyll a has not largely change. These results indicate that heavy frequent precipitation strongly limited the growth of cyanobacteria, and lead an algal succession by the appearance of new algal groups.

• Journal of the Korean Society of Industry Convergence
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• v.27 no.5
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• pp.1069-1080
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• 2024

Recently, vision-based displacement(VBD) has been attracting attention as a convenient and economical method. VBD has the advantage of being easy to install and operate, but it also has the disadvantage of being difficult to obtain results that reflect high-frequency characteristics well. On the other hand, indirect displacement measurement through double integration of acceleration may in some cases result in distortion in the low-frequency region, making integration itself impossible. Therefore, neither can be a suitable method alone for measuring the dynamic displacement of bridges under moving loads. In this context, this paper studies how to obtain more accurate dynamic displacement responses of bridges over the entire frequency range by combining two methods, VBD and acceleration integration. The practical applicability was examined through simulation and model experiments. The simulation results show that both basic methods have fundamental limitations in each frequency range, while the combined method can be an good alternative to overcome these limitations. The applicability of the combination method through model experiments also showed relatively good results, but the results were inferior to those in the theoretical case. The reason is that errors in each basic measurement methods are transferred to the combined method. In other words, it is important that the basic measurement method also secures sufficient accuracy at least in each advantageous frequency band. In conclusion, combining the strengths of different methods to create a better alternative is always a good approach, and the method in this paper is meaningful in that it demonstrates one such alternative.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.17 no.6
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• pp.277-282
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• 2007

The artificial lightweight aggregate (ALA) was manufactured using coal bottom ashes produced from a thermoelectric power plant with clay and, the sintering temperature and batch composition dependence upon physical properties of ALA were studied. The bottom ash (BA) had 13wt% coarse particle (>4.75mm) and showed very irregular shape so should be crushed to fine particles to be formed with clay by extrusion process. Also the bottom ash contained a many unburned carbon which generates the gas by oxidation and lighten a aggregate during a sintering process. Plastic index of green bodies decreased with increasing bottom ash content but the extrusion forming process was possible for the green body containing BA up to 40wt% whose plastic index and plastic limit were around 10 and 22 respectively. The ALA containing $30{\sim}40wt%$ BA sintered at $1100{\sim}1200^{\circ}C$ showed a volume specific density of $1.3{\sim}1.5$ and water absorption of $13{\sim}15%$ and could be appled for high-rise building and super-long bridge.

• Journal of the Korean Institute of Landscape Architecture
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• v.30 no.1
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• pp.52-60
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• 2002

This paper presents a streetscape design for "Dangiae-Gil"which is located at 126-1 Yangpyung-2dong, Yeongdeungpo-gu, Seoul and is about 500m in length and about 24m in width. The design goals are to make a green street on which people want to walk and people can walk and rest safely and pleasantly. To achieve these goals, concepts of environmentally-friendliness, placeness, safety, amenity, vitality, connectivity, and democracy are developed. For pedestrian safety, shared street concepts, such as crank, slalom etc. are adopted. The site is divided into 5 thematic spaces, such as "Village Entrance Space", "Culture Street", "Dangsan Park", "Nature Street", and "Ferry Space". The Village Entrance Space, which is an entrance of the Dangjae-Gil and a welcoming space, is for communicating information about the area. "Dangnamu"(zelkova tree) and signs are introduced here. The Culture Street is for experiencing past and present culture of the area. Colored tiles and plant boxes attached to benches are introduced. The Dangsan park is a sacred space where modem people can feel the sacredness of nature arid of being in a refuge. Dangjib, Dangnamu, multi-purpose plaza, athletic facilities, and playground for infants are introduced. The Nature Street is a space for feeling and teaming nature which has disappeared from the area leading to the river and a space for community participation. The elementary school walls were demolished and nature education spaces, such as butterfly and dragonfly garden, ecological pond, wildflower garden, etc., which are related to school education, are introduced. The Ferry Space is a space symbolizing a old ferry crossing and an entrance plaza to a bridge for "Sunyu-do\" . A boat-shaped deck, an elevator for handicap people, and parking space are introduced. In conclusion, sustainable management schemes for the site are suggested.sted.

• Journal of the Korean Society of Safety
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• v.32 no.6
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• pp.98-103
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• 2017

In Korea, the guideline for the bridge safety inspection requests to assess surface degradation, including crack, efflorescence, spalling, and so on, for the rating of concrete bridges. Currently, the assessment of efflorescence is performed based on the visual inspection of expertized engineers, which may result in subjective inspection result. In this study, a novel method using a hyperspectral camera is proposed for objective and accurate assessment of concrete efflorescence. The hyperspectral camera acquires the light intensity for a number of continuous spectral bands of light for each pixel in an image, which makes the hyperspectral imaging technique provides more detailed information than a color camera that collects intensity for only three bands corresponding to RGB (red, green, and blue) colors. A stepwise assessment algorithm is proposed based on the spectral features to decompose efflorescence area from the inspected concrete area. The algorithm is tested in the laboratory test using two concrete specimens, one of which is dark colored with efflorescence on a surface while the other is bright concrete without efflorescence. The test shows high accuracy and applicability of the proposed efflorescence assessment using a hyperspectral camera.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.12
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• pp.2126-2131
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• 2006

This paper proposes an international trend and its implementation for an E-Navigation that can utilize of existing and new navigation tools, in particular electronic tools, in a holistic and systematic manner. IMO develops a broad strategy for incorporating the use of new technologies in a structured way to ensure that their use is compliant with the various electronic navigational and communication technologies and services that are already available. Implementation of this new strategic vision might require modifications to working methods and navigational tools, such as chats, bridge display equipment, electronic aids to navigation, communications and shore infrastructure. E-Navigation will reduce navigational accidents errors and failures by developing standards an accurate and cost effective system.

• Journal of Forest and Environmental Science
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• v.31 no.2
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• pp.136-148
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• 2015

Hyangro-bong is located on the northern side of the civilian access control line and therefore has gone through natural ecological succession without human interference. Currently, it forms a distinctive natural ecosystem in which rare wild animals and plants are various. It is located in the Baekdudaegan mountain system and plays an ecologically important role as a bridge that connects the Geumgang mountain and Seorak mountain. This study investigated the flora of the eastern parts, Forest Genetic Resources Reserve Area, of Hyangro-bong. A total of 363 vascular plants that belonged to 77 families, 206 genera, 310 species, 3 subspecies, and 47 varieties were found in the study area. Rare and endangered plants identified in this study included the critically endangered Swertia wilfordii and endangered Irisuniflora var. caricina. Furthermore, 4 vulnerable species, Hanabusaya asiatica, Codonopsis pilosula, Leontopodium japonicum, and Taxus cuspidata, were found. A total of 7 families and 14 taxa including Aconitum pseudolaeve and Clematis fusca var. coreana were confirmed as endemic plants. Naturalized plants belonging to 4 families, 11 genera, and 13 species were distributed along the Hyangro-bong forest roads.

• Journal of Industrial Technology
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• v.19
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• pp.269-278
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• 1999

When a variety of repeated loads are given, most steel structures failed in much lower level of loads than static failure loads. In addition, bridge always includes the internal defects or discontinuities. from these, fatigue cracks initiates and can lead to sudden failure. Thus, in this study, tensile specimens by the cover plate shapes were used as the test specimens. The fatigue test was performed by constant amplitude fatigue loading and beach mark. From the results of this study, each specimen's fatigue section was observed. in addition, stress intensity factor at crack tip was calculated by using the Green's function which applied to discontinuous section where causing stress concentration. Therefore, the fatigue life of structural detail was investigated by adopting the theories of fracture mechanics. each specimen's crack shape is a semi-elliptical surface crack or center crack sheet, stress gradient correction factor, Fg is the most subjective of all stress intensity correction factors and fatigue life should be predicted by previous proposed function and finite element analysis.

• English & American cultural studies
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• v.10 no.2
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• pp.209-230
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• 2010

This paper reads Tristram Shandy around the issue of hobbyhorse, Sterne's main contribution to novelistic techniques as well as his insightful understanding of the modern condition. First, Sterne represents his characters according to the principle of hobbyhorse, declaring "I will draw my uncle Toby's character from his HOBBY-HORSE." Gradually distancing himself from the Juvenalian satiric mode as well as Henry Fielding's grand narrative and Samuel Richardson's psychological realism, as is seen in the early episode of Yorick's death, Sterne suggests that the best way to represent his characters lies in describing their hobbyhorses. Sterne's foregrounding of hobbyhorse is linked with his embrace of madness as part of the modern identity. He accepts that hobbyhorse-riding, a quirky and mad habit of mind or behavior, is indispensable for some people, like Uncle Toby, to survive and get along with their otherwise unbearable lives. Uncle Toby's hobbyhorse of waging mock battles in the bowling green saves him from the perplexing real world of language and sexuality, while the fictionality of his hobbyhorsical world is exposed by Widow Wadman. Since a hobbyhorse is by definition a world of private pleasure and eccentricity, sentimentalism comes along to bridge the two virtually incommensurable hobbyhorsical world in place of linguistic communication. Yet if Tristram Shandy fully stages sentimentalism, a cardinal part of hobbyhorse riding, it also offers an awareness of it, which is a significant development in the cult of sentimentalism in the eighteenth century. Tristram Shandy performs a version of sentimental journey where each character rides his hobbyhorse and the reader is invited to ride his/her own hobbyhorse.