• Journal of The Korean Astronomical Society
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• v.51 no.2
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• pp.37-48
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• 2018

Massive stars blow powerful stellar winds throughout their evolutionary stages from the main sequence to Wolf-Rayet phases. The amount of mechanical energy deposited in the interstellar medium by the wind from a massive star can be comparable to the explosion energy of a core-collapse supernova that detonates at the end of its life. In this study, we estimate the kinetic energy deposition by massive stars in our Galaxy by considering the integrated Galactic initial mass function and modeling the stellar wind luminosity. The mass loss rate and terminal velocity of stellar winds during the main sequence, red supergiant, and Wolf-Rayet stages are estimated by adopting theoretical calculations and observational data published in the literature. We find that the total stellar wind luminosity due to all massive stars in the Galaxy is about ${\mathcal{L}}_w{\approx}1.1{\times}10^{41}erg\;s^{-1}$, which is about 1/4 of the power of supernova explosions, ${\mathcal{L}}_{SN}{\approx}4.8{\times}10^{41}erg\;s^{-1}$. If we assume that ~ 1 - 10 % of the wind luminosity could be converted to Galactic cosmic rays (GCRs) through collisonless shocks such as termination shocks in stellar bubbles and superbubbles, colliding-wind shocks in binaries, and bow-shocks of massive runaway stars, stellar winds might be expected to make a significant contribution to GCR production, though lower than that of supernova remnants.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.338.1-338.1
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• 2002

The efficient Erythropoietin(EPO)-expression system in mammalian cells is required for massive production for therapeutic use. Ammonium ion is a major problem in the production of useful proteins by cultured animal cells and therefore it is of importance to devise a system by which a high productivity of human therapeutic recombinant protein can be maintained or enhanced under low ammonium concentration. (omitted)

• Proceedings of the Microbiological Society of Korea Conference
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• 2008.05a
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• pp.131-132
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• 2008

• Management & Information Systems Review
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• v.7
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• pp.227-245
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• 2001

The object that we have researched the design for a long life of product is to search for the method to cope with the various environment problems where our mankind is confronting in the field of Production Design. The environment problem on earth is affecting seriously the enterprise which produces the product, the user who consumes it and even the field of product design. Now we live our daily life with a lot of artifacts while the citification and modernization have been progressing around us. Especially, 20 century was the times of the highly advanced scientific civilization and industrialization. Therefore it affected decisively our life environment base nowadays. The result was that our human life became rich because of the advanced development of industry, productivity and distribution structure. On the other side, the industrial system in the period of these massive production and massive consuming is bearing various problems proportionally. Those are the depletion of resources and energy, earth environmental pollution and various kinds of waste. In addition, the material which cannot recycle is appearing at the large quantity. This is the actuality of now. Our subject is how product design will cope with it as counter measures and the subject is very important to our mankind and earth environment.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.1
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• pp.39.1-39.1
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• 2019

Not all stars in the Universe are gravitationally bounded to galaxies. Since first discovered in 1951, observations have revealed that a significant fraction of stars fills the space between galaxies in local (low-redshift) galaxy clusters, observed as diffuse intracluster light (ICL). Theoretical models provide mechanisms for the production of intracluster stars as tidally stripped material or debris generated through numerous galaxy interactions during the hierarchical growth of the galaxy cluster. These mechanisms predict that most intracluster stars in local galaxy clusters are long-accumulated material since z~1. However, there is no observational evidence to verify this prediction. Here we report observations of abundant ICL for a massive (above $10^{14}$ solar masses) galaxy cluster at a redshift of z=1.24, when the Universe was 5 billion years old. We found that more than 10 per cent of the total light of the cluster is contributed by the diffuse ICL out to 110 kpc from the center of the cluster, comparable to 5-20 per cent in local, massive galaxy cluster. Furthermore, we found that the colour of the brightest cluster galaxy located in the core of the cluster is consistent with that of the ICL out to 200 kpc. Our results demonstrate that the majority of the intracluster stars present in the local Universe, contrary to most previous theoretical and observational studies, were built up during a short period and early (z>1) in the history of the Virgo-like massive galaxy cluster formation, and might be concurrent with the formation of the brightest cluster galaxy.

• Journal of the Korean Geotechnical Society
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• v.36 no.8
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• pp.17-25
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• 2020

Korea Institute of Civil Engineering and Building Technology has constructed a large scale Dust Thermal Vacuum Chamber to simulate extreme lunar terrestrial environments and to study the Moon as an outposts for space development and exploration. Although a large amount of KLS-1 (Korean Lunar Simulant-1) is required for research, its massive production is practically difficult. This paper describes semi-automatic manufacturing system for massive production of KLS-1 in detail, which is seven times more efficient than manual production. In addition, to increase the similarity with lunar regolith, hydrogen reduction reaction using ilmenite which is one of the minerals was also conducted to simulate nanophase Fe(0) which is the unique property of lunar regolith. As a result, it was found that np-Fe(0) was formed at a temperature of 700℃ or higher, and increased in proportion to the temperature until 900℃.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11c
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• pp.764-769
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• 2000

A new transplant production system that produces high quality plug seedlings of specific crop has been studied. It is a plant factory designed to produce massive amount of virus free seedlings. The design concept for building this plant factory is to realize maximum energy efficiency and minimum initial investment and running cost. The basic production strategy is the sitespecific management. In this case, the management of the growth of individual plantlet is considered. This requires highly automated and information intensive production system in a closed aseptic environment the sterilized specific crops. One of the key components of this sophisticated system is the irrigation system. The conditions that this irrigation system has to satisfy are: 1. to perform the site specific crop management in irrigation and 2. to meet the no waste standard. The objective of this study is to develop an irrigation scheduling that can implement the no waste standard.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.23 no.58
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• pp.89-100
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• 2000

There use many production management systems for increasing productivity, minimizing inventory, keeping due dates and maximizing use of resources. MRP, GT and JIT are popular among these systems. There use many production management systems for increasing productivity, minimizing inventory, keeping due dates and maximizing use of resources. MRP, GT and JIT are popular among these systems. In this study, we had designed mixed production system which integrated searching and grouping function of GT, purchasing function of JIT and based on MRP and developed related algorithms and applied systems. The developed system was based on appling renewed algorithms for existing MRP system. To test efficiency operated real-data but we have tested renewed algorithms using sample-data because of massive real-data.

• Journal of The Korean Society of Clinical Toxicology
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• v.6 no.1
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• pp.42-44
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• 2008

Metformin which is an oral hypoglycemic agents, acts by enhancing insulin sensitivity, decreasing hepatic glucose production and increasing peripheral utilization of glucose. Deliberate self poisoning with oral hypoglycemic agents is rare. The lactic acidosis associated with metformin toxicity is well described in the medical literature. Metformin overdose even in otherwise healthy patients may produce a profound and life threatening lactic acidosis. We report a case of massive metformin ingestion(75g) in a patient presenting with lactic acidosis and hypotension. She died 24h after presenting to our emergency department despite bicarbonate treatment and hemofiltration therapy.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.1035-1040
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• 2003

This research investigates the actual data and construction technology of the massive bottom slab placed by $23,000m^3$ concrete quantity in site of the in-ground type LNG receiving terminal having 20,000kl storage capacity. The purpose of this study is to determine the optimum mix design and control the actual concreting procedures including concrete production, transportation, placement, vibrating and curing in site. For this purpose, the optimum mix design using ternary blended cement(furnace slag cement＋fly ash) and under piping method having 11 gates and 7 distributors are selected. As test results of actual construction, concrete placement is finished during 68hours with good success and obtained the good quality of the fresh and hardened concrete including slump, air contents, no-segregation, compressive strength and low hydration heat. Also, actual data for all of concrete procedures are proved successful and satisfied with our specifications.