• Computational Structural Engineering
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• v.4 no.3
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• pp.51-54
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• 1991

금성사는 뉴미디어 서비스, 컴퓨터와 종합정보 통신망의 결합 등 2000년대 신시장에 대한 적극적인 도전과 국내시장 개방에 대한 대처는 물론 주요 고기능 시스템을 운영할 수 있는 첨단 소프트웨어의 자체개발력 구축을 통한 국제 경쟁력을 강화하기 위하여 국산 워크스테이션을 개발하게 되었다. 썬사의 스팍스테이션 1과 100% 호환성을 갖는 MIRACLEstation 20은 스팍 RISC칩을 장착했고 운영체제는 썬 OS4.1, 또한 스팍스테이션에서 운용되는 모든 소프트웨어를 수정없이 사용할 수 있어 CAD/CAM/CAE, 금융, Software Engineering, Simulation, 국방, GIS 등의 분야에 3,300여종의 소프트웨어가 지원되는 워크스테이션이다. 이 제품은 207MB 하드디스크 1개와 1.44MB 플로피디스크 1개를 내장했고, 이더넷, TCP/IP, ONC/NFS를 기본 사양으로 LAN 및 WAN 환경에서 동기종 뿐만 아니라 타기종과 인터페이스를 용이하게 함으로써 워크스테이션의 필수요건인 네트워킹을 완벽하게 구현한다. 특히 국내 최초의 양산에 성공한 썬 클론 제품으로서 가격대비 성능면에서 뛰어난 제품이다.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.237-238
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• 2000

전복양식산업은90년대 이후 비약적으로 발전하여 현재는 남해안을 중심으로 전국적으로 넙치양식과 함께 육상수조 및 해상양식에서 큰 비중을 차지하고 있다. 1999년도의 양식현황은 종묘생산 건수가 177건, 수면적 6만7천$m^2$, 연간 생산능력 5천5백만 마리로 나타나고 있으며, 지역별 생산 능력은 남해안 및 제주도가 전국대비 각각 62%, 5.9%, 동해안은 6.3%, 서해안은 25.4%를 차지하고 있다. 이처럼 전복양식 산업의 꾸준한 발달과 규모의 증가 추세로 인하여 전복 종묘에서부터 성패까지 성장 단계별로 선별. 분산기회가 많아지고, 성패의 출하시기에도 많은 양의 박리가 이루어지기 때문에 효율적이고 경제적인 박리방법이 필요하다. 특히, 일시에 대량으로 마취 박리를 할 수 있고, 생물에 대한 상처로 인한 폐사를 줄일 수 있는 안정적이고 효율적인 마취박리 방법이 절실히 요구되고 있다. (중략)

• Fire Science and Engineering
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• v.30 no.6
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• pp.1-8
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• 2016

In cars, the amount of combustibles, such as plastics, textiles, etc., have increased dramatically to improve the fuel efficiency of cars by reducing the gross vehicle weight according to the increases in an oil price and to reduce environmental problems. One or two cars were involved in a parking lot fire prior to the mid-2000 s. On the other hand, there were many parking lot fires where the entire car was destroyed due to increasing the use of plastics. In this study, the quantity of combustibles in a car was 316.2 kg over a total weight 1935 kg. This is 16.34% of total weight and 10 times greater than that three decades earlier. When a sprinkler is installed as a parking lot fire protection system as a substitute for water spray, the water discharge of the sprinkler must maintain the original density of water spray, $20lpm/m^2$. In addition, the use of a hose reel $CO_2$ system at pilotis parking lots must be prohibited because the hose reel $CO_2$ system has no adaptability for a car fire. Instead, this study proposes foam, dry powder, loaded stream systems be used in parking lot fire suppression systems.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.1
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• pp.69-77
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• 2012

After lunar explorations were restarted in 1990s, the world space advanced countries have been competing actively to preoccupy the Moon from the 2000s. Korea has been also conducting precedent study on lunar exploration to carry out that by ourselves in 2020. This study analyzed delta-V of various Earth-Moon transfer trajectories for minimization of fuel consumption. Through the simulation, the best Earth-Moon transfer trajectory for Korean lunar mission is suggested and it will be used as useful materials of Korean lunar mission.

• Journal of the Korean Geographical Society
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• v.51 no.5
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• pp.713-737
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• 2016

This study is to review research issues on North Korea and unified territory in terms of topics and approach method in Korean human geography. The conclusion of this paper is as follows. Before 1980's, topics on political geography, such as geopolitics or unified land, were the main stream in research. In 1990's with the end of the cold war and the access to material which was published in North Korea, scope of research was widened especially in geography education. After 2000's with the expansion of cooperation between South and North Korea, the scope of topics were more expanded in all field of human geography, for example, critical geopolitic in political geography, Gaeseong Industrial Complex, Najin-Seonbong region in economic geography, place names, Geumgangsan, North Korean defectors in social and cultural geography. The approach method of toward North Korea is fall into two categories. One is regional geography and the other is the unified land. In the latter approach, topics on the regional structure after reunification or on the life adaptation of defectors in South Korea etc. were studied. After unification of land, new Korean Studiea will be established and human geographers should make ready for this. Before unification, research on the land in north Korea should be proceeded in terms of historical geography.

• Resources Recycling
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• v.32 no.6
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• pp.67-78
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• 2023

The rare metals used as raw materials in high-tech industries undergo changes in demand structures and supply chains following domestic industrial structural shifts and technological advancements, exhibiting high price volatility. Therefore, it is necessary to periodically analyze changes in the demand structures of rare metals. Since domestic demand for most rare metals relies on imports in Korea, the changes in domestic demand for rare metals can be identified by analyzing changes in their trade structure. In the present study, we analyze the changes in trade volume, trade growth rate, trade rankings, and trading countries from 2000 to 2022 for 35 rare metals, categorized into five types-ores, metals, alloys, compounds, and scrap. The trade of the raw materials of rare metals in Korea has generally increased since the 2000s, except for a significant decline in 2009 and 2016. The total trade volume, encompassing both exports and imports, has increased by approximately tenfold in 2022 compared to 2001. Until the mid-2010s, the trade of the raw materials of rare metals was primarily focused on those used in steel-manufacturing such as silicon, nickel, chrome, molybdenum, manganese, and others. However, after that period, there has been an increase in the trade of platinum group metals like palladium, rhodium, platinum, and the raw materials of rare metals for secondary battery-manufacturing such as lithium and cobalt. Particularly in 2022, lithium has become the largest share in trade of the raw materials of rare metals in Korea, due to the price surge and increase in demand.

• Information Systems Review
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• v.24 no.4
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• pp.41-54
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• 2022

Despite the recent rapid advancement of science and technology, we have been experiencing the decline in productivity since the 2000s. This study aims to investigate the decline at both industry and firm levels, by looking at the emergence and growth of large firms such as Amazon, Alphabet, and Apple and M&A trends. Following the results of previous studies, our results show that productivity at industry level has decreased since the 2000s. Particularly, in the period after 2011, the deterioration of allocative efficiency due to the large firms and the decline in the growth rate of surviving firms in the industry with low ratio of large firms contributed to the productivity decline. On the other hand, our analysis at firm level demonstrates that the productivity of firms that acquired IT firms improved over the entire period. While M&As have a positive impact on productivity, M&As with a demand-side motive such as market penetration and expansion of channels have a relatively larger impact than the ones for production or operation efficiency. Our results also suggest that the higher the proportion of large firms in a specific industry, the lower the productivity of individual firms in the same industry. Overall, given that the industry's structural changes for digital transformation tends to strengthen the growth of large firms, our findings have significant implications by empirically identifying the relationships of the emergence of large firms, the acquisition of IT/Non-IT firms, and motivations for M&As to firm/industry productivity.

• Archives of design research
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• v.13 no.4
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• pp.85-93
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• 2000

Design becomes a source of new competitive power in the boundless global market so-called globalization. The competitive power in business was lied in the technology in 70's and the design was understood as a styling or graphic means. However, the design has become more important means to get the competitive power in business since 1980. World businesses have found the fact that it has a super competitive power to make the product's performance as well as its dignity rather than it is to determine the product's external view or color. The change of design policy in Phillips, one of the world's leading producers of electronic products, is not much different. Design manager's power was limited until 70's. However, Phillips has focused its business strategy on the higher competitive power since 1980 and they welcomed Robert Blaich, vice president of design and development at Herman Miller Inc., to be a member of the company, expanding the importance of design along with restructure while working on the globalization. Meanwhile, Stefano Marzano, a Senior Director in 90's, established a high design concept, working on the strategic futures to get customer-oriented and for successful commercialization. The vision of the future developed over 3 years until 1996 was to forecast 10 years coming up and create a new value while achieving the business target through the design as an innovative design in bracing for the information network era.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.430-430
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• 2011

최근 지구온난화, 엘리뇨 및 라니냐 등 지구환경 변화에 따른 기후변화의 영향으로 짧은 시간에 매우 높은 강도를 가진 이상호우에 의해 많은 인명과 재산피해가 발생하고 있다. 우리나라의 경우에도 1990년대 후반부터 과거와 달리 국지적 집중호우가 빈번히 발생하고 있으며 집중호우에 의한 홍수는 우리나라의 가장 빈번한 자연재해 중 하나가 되었다. 이러한 성격의 홍수는 소유역 규모의 좁은 지역과 급경사지역에서 짧은 지속시간과 집중적인 강우강도에 의해 발생하고, 빠른 유속과 토사를 동반하는 빠른 수문반응으로 홍수에 대비할 시간이 부족한 것이 특징이기 때문에 기존의 홍수예보모형을 이용하여 발생홍수의 특성을 예측하기에는 많은 어려움이 있다. 유출수문곡선의 특성을 분석하여 홍수의 특성을 분석하는 연구는 Kyiamah (1996)가 유출수문곡선의 기초적인 상승곡선, 지체시간, 첨두홍수량을 이용하여 돌발홍수사상에 대한 크기를 산정하였으며, 이를 바탕으로 Bhaskar 등 (2000)은 유출수문곡선의 상승부 기울기, 첨두 홍수량비, 홍수 반응시간을 이용하여 돌발홍수지수(Flash Flood Index)를 산정하고 이 지수에 의해 돌발홍수를 설명하고자 하였다. 국내에서는 정재철 (2000)이 보청천을 대상으로 단 몇 개의 사상만을 대상으로 Bhaskar 등 (2000)이 제시한 돌발홍수지수를 적용한 바가 있다. 그러나, 이들 연구에서는 소수의 수문사상만을 이용하였기 때문에 상대심도를 산정하는데 있어 문제가 있으며 상대심도를 산정하는데 있어 각 심도계수들의 임의적인 도수분포를 이용하였기 때문에 매우 주관적이라고 할 수 있다. 김병식 등 (2008)은 한강유역의 과거 101개의 홍수사상에 대해 돌발홍수의 상대심도를 파악하기 위하여 돌발홍수지수를 산정하고 2006년 7월의 집중호우에 의해 발행한 홍수사상의 돌발홍수 심도를 시간 및 공간적으로 정량화하였다. 이러한 기존의 연구는 홍수심도 산정시에 필요한 유출수문곡선을 실측된 자료를 이용하여 산정하였으나 국내의 소유역의 경우 실측된 유출수문곡선 자료가 그다지 많지 않은 관계로 인해 홍수심도를 산정하는데 많은 어려움을 내포하고 있다. 따라서 본 연구에서는 미계측 소유역중 시범유역을 선정하고 30년 이상 장기간 실측 강우의 기왕최대 시강우량 자료에 대하여 강우-유출모형을 통한 홍수유출수문곡선을 모의한 후, 빈도별 확률강우량에 대한 수문곡선 특성인자들의 비를 무차원 지수화하여 극한홍수사상에 대한 설계강우의 취약성을 평가하기 위한 홍수위험지수 (Flood Hazard Index) 산정방법을 제시하였다.

• Korean Journal of Food Science and Technology
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• v.44 no.1
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• pp.106-113
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• 2012

The present study was conducted to assess the dietary exposure to mercury and the associated risks for Koreans resulting from their food intake. The probabilistic approach in the Monte Carlo simulation was used to estimate dietary exposures. Based on several reports regarding heavy metals published by KFDA in the 2000s, 178 types of representative foods were selected and data were collected on the occurrence of mercury. The contents of mercury in foods ranged: agricultural products 0.1 (fruits)-45.4 ${\mu}g/kg$ (mushrooms), 3.7 ${\mu}g/kg$ (meat), and 9.3 (Echinodermata, chordata)-194.9 ${\mu}g/kg$ (fish). Others categories investigated were alcoholic beverages (0.7 ${\mu}g/kg$) and processed food (4.4 ${\mu}g/kg$). The mean and 95th percentile for exposure to dietary mercury were 4.29 and 12.48 ${\mu}g/day$, corresponding to 13.6% and 39.7% of PTWI (Provisional Tolerable Weekly Intake), respectively. Therefore, overall level of mercury exposure for Koreans through food intake is below levels recommended by JECFA, indicating the least possibility of risk, and is less than or similar to levels reported in other countries.