• Journal of the Korean Geosynthetics Society
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• v.6 no.4
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• pp.29-37
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• 2007

Reduction Factor for Installation Damage required for calculation of design strength of geogrid used in MSEW(mechanically stabilized earth wall) design is usually obtained in the field test simulating real construction condition. However, damages occurred in geogrid during backfill work are influenced by many factors such as polymer types, unit weight per area, backfill construction method and gradation of backfill material and field test considering these factors demands lots of time and costs. In this study, factors affecting installation damage are analyzed and empirical method for evaluating reduction factor for installation damage using maximum particle size in backfill material is suggested.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.1
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• pp.52.1-52.1
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• 2015

We have recently installed SQUEAN on the 82 inch telescope at the McDonald Observatory, USA. This instrument consists of an ANDOR CCD camera, a focal reducer, an electronic box, an auto guiding system and a new filter wheel which holds up to 20 filters. Currently the filter wheel is equipped with Johnson-Cousins BVRI filters, SDSS rizY and isiz filters, and 50nm medium band pass filters (M625(625nm), M675(675nm), M725(725nm), M775(775nm), M825(825nm), M875(875nm), M925s(925nm), M975(975nm), and M1025(1025nm)). Our medium band pass filter system is suitable with SED fitting. Filter transformation methods are essential for time-domain observations including transient objects, e.g., supernovae, variable stars, and solar system bodies. In this work, we develop a series of equations to convert the open clusters photometry data within these filter systems.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.5 no.6
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• pp.64-71
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• 2002

This study aimed to provide data for establishment of resource management system of Iriomote Island in Okinawa Japan. Nature resource management system of Iriomote Island can be categorized into eight stages which are equivalent to regional development stages. 1) Networking among local people, tourists, researchers, tour operators and government authorities enhanced collection of resource data. 2) On the early stage, resource data were available only to researchers and government authorities. From the third stage of this system, however, local people were also involved in resource investigation, so they became to well recognize the values of their local resources. 3) On the sixth stage, data on unfamiliar local resources and attractions became to be known to people by real-time data collection and data provision services. The tourist number gradually increased and their visitation patterns were dispersed into different sites and seasons. In addition, some tourists also participated in resource investigation and they were likely to visit the place again. 4) To achieve successful ecotourism development, it is necessary to establish a management system with a feed-back process to identify, evaluate, use and protect the resources.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.35 no.4
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• pp.261-268
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• 2017

The topographic volume estimation is carried out for the earth work of a construction site and quarry excavation monitoring. The topographic surveying using instruments such as engineering levels, total stations, and GNSS (Global Navigation Satellite Systems) receivers have traditionally been used and the photogrammetric approach using drone systems has recently been introduced. However, these methods cannot be adopted for inaccessible areas where high resolution satellite images can be an alternative. We carried out experiments using Kompsat-3/3A data to estimate topographic volume for a quarry and checked the accuracy. We generated DEMs (Digital Elevation Model) using newly acquired Kompsat-3/3A data and checked the accuracy of the topographic volume estimation by comparing them to a reference DEM generated by timely operating a drone system. The experimental results showed that geometric differences between stereo images significantly lower the quality of the volume estimation. The tested Kompsat-3 data showed one meter level of elevation accuracy with the volume estimation error less than 1% while the tested Kompsat-3A data showed lower results because of the large geometric difference.

• Journal of Astronomy and Space Sciences
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• v.32 no.4
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• pp.349-355
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• 2015

As a governmentally approved domestic entity for Space Situational Awareness, Korea Astronomy and Space Science Institute (KASI) is developing and operating an optical telescopes system, Optical Wide-field PatroL (OWL) Network. During the test phase of this system, it is necessary to determine the range of brightness of the observable satellites. We have defined standard magnitude for Low Earth Orbit (LEO) satellites to calibrate their luminosity in terms of standard parameters such as distance, phase angle, and angular rate. In this work, we report the optical brightness range of five LEO Satellites using OWL-Net.

• Journal of Magnetics
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• v.21 no.3
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• pp.315-321
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• 2016

M-Zn (M = Sb, V, Nb) substituted M-type strontium hexaferrites were prepared by a ceramic method. The phase composition, morphology and magnetic properties were studied by x-ray diffractometry, scanning electron microscopy and vibrating sample magnetometry. Saturation magnetization increases with a substitution up to 75.0 emu/g (2.5 % higher compared to unsubstituted hexaferrite) and then decreases with a further substitution. A coercive field of substituted hexaferrite powders with highest saturation magnetization is more than 3 kOe. Substituted strontium hexaferrite powders prepared in this work are a rare example of high $M_S$ compositions without doping rare-earth elements and would be a promising candidate for a permanent magnet application.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2002.05a
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• pp.119-122
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• 2002

The vibration qualification test of satellite antenna is required to verify that there will be no structural damage due to the severe vibration caused by the launch of satellite. For the qualification test, reasonable test load condition needs to be introduced by dynamic analysis. The present work has been performed to provide an understanding how the qualification test load can be evaluated by the results of both normal mode and sine vibration analyses with notching technique for a composite Ka-band antenna structure.

• Journal of Korea Game Society
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• v.18 no.2
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• pp.5-14
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• 2018

Main purpose of this research is to discuss relationship between digital art works and audience by expansion of Body Schema from Maurice Merleau Ponty's viewpoint, and artistic value of digital art works also became discussed in this research, based on Heidgger's concept called 'Defamiliarization'. We found this 'Defamiliarization' became an important role of digital art works caused by interaction between arts and audience. And we also discussed audience's role as a poet, being-in-between in between the earth and the world, gods and mortals called Heidegger's 'fourfold'. As a conclusion, this unique experience compared to other works is called "A shamanic experience", as an artistic value in interactive digital art works.

• KSBB Journal
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• v.30 no.6
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• pp.257-267
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• 2015

Insects are the most successful organisms on earth in terms of their diversity and adaptability. Insect biotechnology using this insect resource is an emerging area for future biotechnology with various applications. Insect resources have long been used to make food and/or functional food, feed, cosmetics as well as medicine and industrial ingredients. Recently, one of the most well-known industrial material from insect is spider silk that could be commercialize in near future. The insect cell lines have been used to express recombinant proteins that were difficult to be functional expression. For public purpose, while, the insect could be good amenity source and plant farming, so leisure resource. Only the interdisciplinary research will guarantee the successful story for insect biotechnology. And biochemical engineers should used insect as a bioresource for new products with applications in medicine, agriculture, and industrial biotechnology in near future. This review will cover state-of-the art of this field and the research and application areas of insect biotechnology and the possible role of biochemical engineer for the development of the future biotechnology using this bioresource.

• Journal of Korean Society for Atmospheric Environment
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• v.15 no.E
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• pp.73-79
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• 1999

To Characterize the single raindrops as a function of their size we designed the sampling and handling apparatuses. Samplings of single and size- classified raindrops were performed at a height of 20m above the ground level of a Kyoto University building located in Uji, Japan in rain events from middle of July to the end of August, 1999. And PIXE method was applied to the analysis of single raindrops sampled as a function of their size. Diameter change of frozen raindrops by liquid nitrogen did nto affect the size segregation ability of our sampling apparatus. The number of raindrops increases with decreasing drop size. And it is found that the size distribution of raindrops verified depends on the rain events. Application of PIXE analysis to the measurement of single raindrops was very successful. Every element showed a continuous increase in concentration with decreasing raindrop diameter. It seems reasonable to say that our work should be helpful to obtain more detailed information on single raindrops and especially to study on the rainout and washout mechanisms.