• Proceedings of the Plant Resources Society of Korea Conference
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• 2021.04a
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• pp.10-10
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• 2021

Natural products have been used as drugs and cosmetics due to their bioactivity and their biochemical diversity. Natural products usually refer to secondary metabolites produced by various living organisms including marine animals, insects, microbes, amphibians, and plants. These secondary metabolites, which usually have molecular weights less than 2,000 amu, are unnecessary for survival, development, growth, and reproduction but play major roles in plant defense systems against other species. These secondary metabolites such as lignans, flavonoids, monoterpenes, and phenylethanoid glycosides showed various biological activities like anti-oxidant behavior, anti-cancer properties, neuroprotective properties, and so forth. Thus, isolation and elucidation of secondary metabolites from living organisms is of great significance to human life.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2006.05a
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• pp.161-165
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• 2006

삼겹에 있어서 SA, 양파 그리고 마늘의 첨가로 FFA 값은 저장 28일에 대조구와 비교하여 각각 14, 31 그리고 53% 감소하였으나 등심에서는 효과가 없었다. 삼겹에서 과산화물의 생성률은 SA처리구를 제외하고 천연소제 첨가에 의해 감소되었다. 그러나 등심에서는 마늘을 제외하고는 천연소제 첨가에 의한 효과는 없었다. 삼겹과 등심 모두에서 휘발성 산화 생성물들은 천연소제에 의한 주목할 만한 효과는 없었다. 삼겹에서 마늘과 양파는 저장성을 연장시킴으로써 항미생물 효과를 보였다. 본 연구에 사용된 천연 물질들은 항산화 및 항미생물 효과를 보였다. 특히 마늘은 지방을 포함하는 식품에서 안정화를 위한 천연 자원으로써 고려되어져야 할 것이다.

• The Korean Journal of Air & Space Law and Policy
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• v.24 no.2
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• pp.187-210
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• 2009

Space law(or outer space law) and the law of the sea are branches of international law dealing with activities in geographical ares which do not or do only in part come under national sovereignty. Legal rules pertaining to the outer space and sea began to develop once activities emerged in those areas: amongst others, activities dealing with transportation, research, exploration, defense and exploitation. Naturally the law of the sea developed first, followed, early in the twentieth century, by air law, and later in the century by space law. Obviously the law of the sea, of the air and of outer space influence each other. Ideas have been borrowed from one field and applied to another. This article examines some analogies and differences between the outer space law and the law of the sea, especially from the perspective of the legal status, the exploration and exploitation of the natural resources and environment. As far as the comparisons of the legal status between the outer space and high seas are concerned the two areas are res extra commercium. The latter is res extra commercium based on both the customary international law and treaty, however, the former is different respectively according to the customary law and treaty. Under international customary law, whilst outer space constitutes res extra commercium, celestial bodies are res nullius. However as among contracting States of the 1967 Outer Space Treaty, both outer space and celestial bodies are declared res extra commercium. As for the comparisons of the exploration and exploitation of natural resources between the Moon including other celestial bodies in 1979 Moon Agreement and the deep sea bed in the 1982 United Nations Convention on the Law of the Sea, the both areas are the common heritage of mankind. The latter gives us very systematic models such as International Sea-bed Authority, however, the international regime for the former will be established as the exploitation of the natural resources of the celestial bodies other than the Earth is about to become feasible. Thus Moon Agreement could not impose a moratorium, but would merely permit orderly attempts to establish that such exploitation was in fact feasible and practicable, by allowing experimental beginnings and thereafter pilot operations. As Professor Carl Christol said until the parties of the Moon Agreement were able to put into operation the legal regime for the equitable sharing of benefits, they would remain free to disregard the Common Heritage of Mankind principle. Parties to one or both of the agreements would retain jurisdiction over national space activities. In so far as the comparisons of the protection of the environment between the outer space and sea is concerned the legal instruments for the latter are more systematically developed than the former. In the case of the former there are growing tendencies of concerning the environmental threats arising from space activities these days. There is no separate legal instrument to deal with those problems.

• 한국석유지질학회:학술대회논문집
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• autumn
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• pp.28-46
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• 2001

Natural gas is a mixture of hydrocarbon gases and impurities such as nitrogen, hydrogen sulfide, and carbon dioxide and a clean energy producing no pollution materials for combustion. Currently, the demand of the natural gas is rapidly increasing due to worldwide environmental problems. According to Hubbert's study in the past, the natural gas was predicted as rapidly depleted resources, and then the results led to high gas price and limitation of usage during 1980s. Afterward, the study of natural gas resources based on geology identified the additional natural gas resources that were not considered in Hubbert's study. They are unconventional gas, additional resources in the existed reservoirs, and natural gas in deep subsurface areas. Such additional resouces made the future of natural gas bright and pormised low and stable gas price in the future. Deep natural gas is defined as the gas existing at or below 15,000ft$(4,752{\cal}m)$ in depth from the surface. According to the study from the U.S. Geological Survey(USGS) in 1995, 1,412 TCF of technically recoverable natural gas was remained to be discovered or developed in the onshore of United States. A significant part of that resource base, 114 TCF, exists at deep sedimentary basins, and it shows wide distribution with various geological environments. In 1995, the deep gas contributed to $6.7\% of total supply amount of natural gas in the United States and is expected to be $18.7\% by 201.5. However, the development of the deep gas is a high risky business due to expensive investment and high portion of dry holes, although it is developed. Thus, for developing the deep gas economically, it is necessary to overcome many technical challenges. In this paper, for increasing success rate of the deep gas, 1) geologic and compositional characteristics, and production cost have been analyzed according to depth, 2) technical problems related to deep gas production have been summarized, and 3) finally future study areas for increasing application of the deep gas have been suggested. For reference, this paper was written based on the study results from USGS and Gas Research Institute(GRI), for the United States is doing the most active R&D in the deep gas area, and thus, has many reliable data.

• Journal of agriculture & life science
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• v.45 no.2
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• pp.51-59
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• 2011

This study was conducted to analysis the growth characteristics and the diameter at breast height (10 cm) reached ages in natural stand and platation for the optimal planting density and planting timing of Acer mono for. rubripes. There was high correlation between the DBH and crown diameter (E-W: r=0.82, S-N: r=0.76) in natural stand, and between the DBH and crown diameter (E-W: r=0.76, S-N: r=0.90) in plantation. In natural stand, average reached age on DBH 10 cm was $21.1{\pm}7.0$, and was $9.2{\pm}1.3$ in plantation. Therefore, the collectable timing of sap in artificial planting short approximately 2.3 times over the natural regeneration.

• Resources Recycling
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• v.31 no.6
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• pp.18-24
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• 2022

Dry reduction using natural gas was proposed to recover tin from waste tin oxide generated in a tin bath that was used for controlling the smoothness of architectural glass during production, and the reduction behavior was investigated. The utilized vertical natural gas dry reduction system is capable to process 4 L or 20 kg depending on input raw materials. The system was established by applying the upper intake and lower discharge method. The recovery rate was 97.2% at 800 ℃ and 4 sccm flow rate and increased with the amount of input gas. Hydrogen accounted for 23% of the discharge gas, showing a 16.6% hydrogen conversion rate. The reaction behavior of tin recovered via natural gas reduction provides basic data on the new waste resource reduction/recovery technology.

• The Korean Journal of Petroleum Geology
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• v.14 no.1
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• pp.45-52
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• 2008

The GTL(Gas to Liquids) technology, manufacturing synthesized oil from natural gas, had been developed about 1920 for the military purpose by Fischer and Tropsch, German scientists. And 1960, Sasol company had started commercializing the FT(Fischer-Tropsch) synthesis technology, for the transport fuel in South Africa. Until a recent date, the commercialization of GTL technology had been delayed by low oil price. But concern about depletion of petroleum resources, and development in synthesizing technology lead to spotlight on the GTL businesses. Especially, Qatar, which has rich natural gas fields, aims at utilizing natural gas like conventional oil resources. Therefore, around this nation, GTL plants construction has been promoted. There are mainly 3 processes to make GTL products(Diesel, Naphtha, lube oil, etc) from natural gas. The first is synthesis gas generation unit reforming hydrogen and carbomonoxide from natural gas. The second is FT synthesis unit converting synthesized gas to polymeric chain-hydrocarbon. The third is product upgrading unit making oil products from the FT synthesized oil. There are quite a little sulfur, nitrogen, and aromatic compounds in GTL products. GTL product has environmental premium in discharging less harmful particles than refinery oil products from crude to the human body. In short, the GTL is a clean technology, easier transportation mean, and has higher stability comparing to LNG works.

• Journal of Korean Society of Forest Science
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• v.112 no.3
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• pp.280-289
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• 2023

Diverse native tree species are distributed in Korean forests; however, information on their regeneration strategies is limited. This study analyzed seed rain from 2011 to 2013, seedling emergence, seedling survival, lifespan distribution, and the relationship between seedling mortality and herbaceous vegetation for 3 years, from 2012 to 2014, to understand the natural regeneration and early survival characteristics of Fraxinus rhynchophylla Hance in natural broad-leaved forests. Seed rain and emerged seedling density significantly differed among the years (p < .05). An increase in seed rain was followed by an increase in seedling emergence in the following year. Seed rain in 2013 and seedling emergence in 2014 showed a significant correlation (p < .05), confirming the trait of F. rhynchophylla seeds that germinate in the following year after seed production. Seedlings emerged in late spring and early summer. Of the seedlings, 78% emerged in the early summer of 2014. Most seedlings died immediately after emergence. Of the seedlings that emerged in August 2012, 56% died within 2 months, and 38% of those that emerged in July 2014 died within 1 month. Shade and competition against ground vegetation chiefly affected the seedling survival of F. rhynchophylla. Fraxinus rhynchophylla showed mast seeding, with a large number of seed production in a particular year. A surge of seedling emergence followed in the early summer of the next year. However, most seedlings died in the same year of emergence. Fraxinus rhynchophylla has a high seedling mortality, but mast seeding and the resulting high seedling emergence produce a few survived seedlings, enabling the continuation of the F. rhynchophylla population. Efforts and research on the natural regeneration of native tree species are required to effectively manage natural forests in Korea.

• Journal of Energy Engineering
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• v.7 no.1
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• pp.1-6
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• 1998

We consider the economic analysis of the domestic natural gas DSM (Demand Side Management). Since the demand of the domestic natural gas decreases in the summer and dramatically increases in the winter, the necessity of the DSM that will smooth the demand pattern of the natural gas is emerged. The economic analysis of the DSM program is used as a main tool for screening the DSM. This paper suggests an economic evaluation method for the domestic gas DSM from the perspectives of participants, Korea Gas Corporation, local distribution company, non-participants, and total resource. The high-efficiency gas boiler is selected as a case study to illustrate the economic analysis of the natural gas DSM.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.11b
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• pp.310-311
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• 2003

본 연구에서는 폐수산자원인 불가사리와 조개껍질 분말을 이용한 탈수보조제(물리개량제)의 가능성을 확인하였다. 불가사리와 조개껍질을 이용한 탈수보조제는 유가자원 소모라는 기존의 탈수보조제의 문제점을 보완하여 폐자원의 자원화라는 이점이 있으며 탈수케이크의 함수율을 효과적으로 낮추어 주어 소각등의 후속공정에 도움을 줄 수 있는 것으로 사료된다. 뿐만아니라 천연 비료로 사용되어지는 불가사리의 활용이라는 점에서 탈수슬러지 퇴비화등 자원 재이용에의 적용성 또한 증대시킬 수 있다.