• 제목/요약/키워드: production environments

검색결과 784건 처리시간 0.024초

Can you predict the production performance using the make-ready performance?: Cases on highway construction projects

  • Yong-Woo Kim;Jinwoo Jang
    • 국제학술발표논문집
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    • The 3th International Conference on Construction Engineering and Project Management
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    • pp.914-919
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    • 2009
  • The research investigates for the relationship between the operating performances of the make-ready process and project production performance. To this end, the researchers proposed a metric of PCR (Percentage of Constraint Removal) to measure the make-ready performance. The study measured the production performance in two ways: production planning reliability and progress performance. We hypothesized that how well the make-ready process is performed has an impact on the degree of production performance. The statistical analyses are used to investigate that how operating performance of the make-ready process affects project production performance. The results of the regression analysis support our hypotheses (p<0.25) and correlation coefficients for the relationship between project production performance and make-ready performance are also significant (p<0.05).

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Radiation damage to Ni-based alloys in Wolsong CANDU reactor environments

  • Kwon, Junhyun;Jin, Hyung-Ha;Lee, Gyeong-Geun;Park, Dong-Hwan
    • Nuclear Engineering and Technology
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    • 제51권3호
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    • pp.915-921
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    • 2019
  • Radiation damage due to neutrons has been calculated in Ni-based alloys in Wolsong CANDU reactor environments. Two damage parameters are considered: displacement damage, and transmutation gas production. We used the SPECTER and SRIM computer codes in quantifying radiation damage. In addition, damage caused by Ni two-step reactions was considered. Estimations were made for the annulus spacers in a CANDU reactor that are located axially along a fuel channel and made of Inconel X-750. The calculation results indicate that the transmutation gas production from the Ni two-step reactions is predominant as the effective full power year increases. The displacement damage due to recoil atoms produced from Ni two-step reactions accounts for over 30% out of the total displacement damage.

풍력발전 단지조성을 위한 바람환경 분석 (Analysis of Wind Environments for Siting a Wind Farm)

  • 김현구;최재우;손정봉;정우식;이화운
    • 한국대기환경학회지
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    • 제19권6호
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    • pp.745-756
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    • 2003
  • An analysis of wind environments using computational fluid dynamics and an evaluation of wind resources using measurement data obtained from meteorological observation sites at Homi-Cape, Pohang have been carrid out for siting a wind farm. It was shown that a numerical simulation using computational fluid dynamics would provide reliable wind resource map in complex terrain with land-sea breeze condition. As a result of this investigation, Homi-Cape wind farm with 11.25 ㎿ capacity has been designed for maximum power generation and 25.7 GWh electricity production is predicted.

수학교육용 멀티미디어 개발에 관한 연구 -Jasper 시리즈 사례를 중심으로- (A Study of Mathematics Educational Multimedia Development: Focused on the Jasper Series)

  • 김민경
    • 한국수학교육학회지시리즈A:수학교육
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    • 제39권1호
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    • pp.59-69
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    • 2000
  • In order to serve effective teaching and teaming environments with an appropriate harmony of hard technologies and soft technologies and to contribute to multimedia contents design and development this study shows that the theoretical backgrounds, producing backgrounds, contents scenario, and related research as well as their use and integration into realistic classroom. In our environments, it is believed that it is possible for us to develop effective mathematics educational multimedia development fitting to our culture and emotion. Thus it is urged that the government should support the professional multimedia development & production association enthusiastically.

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A Study on Korean Students' Production and Perception of English Word-final Stop Voicing

  • Kang, Seok-Han
    • 음성과학
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    • 제14권1호
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    • pp.105-119
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    • 2007
  • The purpose of this study is to examine Korean students' production and perception of word-final stop voicing in light of their overseas experience. Subjects were English native speakers, Korean university students with residence experience in America, Korean university students without residence experience in America, and Korean elementary school students. They participated in both production and perception tests. Results showed that the students' production and perception with residence experience in America appeared quite similar to those of the English native speakers. In the production tests, we noticed somewhat different results in temporal and frequency features. The one-year residence in America had some influence on their frequency features, but not the temporal features in the word final stop production. That difference could be seen in the perception tests, too. We could not find any difference in the identification test of the final release environment between the Korean university students who had studied abroad and those who didn't. Rather the difference could be found in the cue influence test in both the final release and non-release environments.

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FTA 환경에서 ODM-OEM Hybrid 형태의 섬유류생산시스템의 공급망 분석 (Analysis of Textile Supply Chain Network with ODM-OEM Hybrid Production System in FTA Environment)

  • 변태상;오지수;정봉주
    • 경영과학
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    • 제30권1호
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    • pp.25-41
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    • 2013
  • This paper presents a supply chain framework with the ODM (Original Design Manufacturing)-OEM (Original Equipment Manufacturing) hybrid production of textile industry in FTA (Free Trade Agreements) environments between Korea and other countries. The proposed supply chain framework with ODM-OEM hybrid production is a unique supply chain that has both domestic production with non-tariff advantages in FTA environment and oversea production with low labor costs. To investigate the validity of the proposed supply chain, we first construct its strategic profit model and supply chain planning and then show that each member of supply chain network-yarn manufacturer, fabric manufacturer, and apparel manufacturer-can maximize their own profits without conflicts among the members. The efficiency of the ODM-OEM hybrid production system is analytically verified in comparison with the general OEM and ODM production model using profit models. Comprehensive numerical examples are provided to illustrate the advantages of the proposed system.

중북부(中北部) 태평양 해산상(海山上) 수층의 박테리아 생체량과 생산력 (Bacterial Biomass and Production in the Water Column Over two Central North Pacific Seamounts)

  • 조병철
    • 한국해양학회지
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    • 제26권3호
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    • pp.255-261
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    • 1991
  • 중앙 북부 태평양의 두 개의 해산(Horizon guyot와 Magellan rise) 상의 수층에서 박테리아의 생체량과 생산력이 1987년 3월에 조사되었다. 이 기간에 관찰된 표층수의 박테 리아 개체수는 (0.9-2.3$\times$10/SUP 8/l/SUP -1/) 빈영양 해역에서 보고 된 박테리아의 개체수에 비해 낮은 값은 나타냈다. 또한 mesopelagic zone 의 박테리아 개체수도 (대 개 < 5$\times$10/SUP 7/l/SUP -1/) 다른 아열대 지역에서 보고 된 것보다 훨씬 낮았다. 표층수에서의 박테리아 생산력(20-466 ng C l/SUP -1/ d/SUP -1/)또한 다른 빈영양 해 역과 비교시 낮았다. 그러나 표층수의 박테리아 생산력을 이 지역에서 발표된 일차 생 산력과 비교한 경우, 유기물의 이용에 있어서 박테리아의 역할이 중요한 것으로 추정 되었다. 이 연구에서 보고 된 박테리아 생산력의 공간적 분포에 대한 자료는 충분하진 않으나, 매우 빈영양인 수서 환경에서 소규모 그리고 대규모적 공간상의 박테리아 생 산력 분포에 대한 연구의 필요성을 제시하고 있다.

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Characterization of L-asparaginase-producing Trichoderma spp. Isolated from Marine Environments

  • Woon-Jong, Yu;Dawoon, Chung;Yong Min, Kwon;Seung Sub, Bae;Eun-Seo, Cho;Hye Suck, An;Grace, Choi
    • 한국해양생명과학회지
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    • 제7권2호
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    • pp.121-128
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    • 2022
  • L-asparaginase (ASNase) is a therapeutic enzyme used to treat acute lymphoblastic leukemia. Currently, the most widely used ASNases are originated from bacteria. However, owing to the adverse effects of bacterial ASNases, new resources for ASNase production should be explored. Fungal enzymes are considered efficient and compatible resources of natural products for diverse applications. In particular, fungal species belonging to the genus Trichoderma are well-known producers of several commercial enzymes including cellulase, chitinase, and xylanase. However, enzyme production by marine-derived Trichoderma spp. remains to be elucidated. While screening for extracellular ASNase-producing fungi from marine environments, we found four strains showing extracellular ASNase activity. Based on the morphological and phylogenetic analyses using sequences of translation elongation factor 1-alpha (tef1α), the Trichoderma isolates were identified as T. afroharzianum, T. asperellem, T. citrinoviride, and Trichoderma sp. 1. All four strains showed different ASNase activities depending on the carbon sources. T. asperellem MABIK FU00000795 showed the highest ASNase value with lactose as a carbon source. Based on our findings, we propose that marine-derived Trichoderma spp. are potential candidates for novel ASNase production.

The Adaptation of Ginseng Production of Semi-arid Environments The Example of British Columbia, Canada

  • Bailey, W.G.
    • 고려인삼학회:학술대회논문집
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    • 고려인삼학회 1990년도 Proceedings of International Symposium on Korean Ginseng, 1990, Seoul, Korea
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    • pp.155-167
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    • 1990
  • Ginseng Is renowned for both its medicinal and herbal uses and successful cultivation of Panax ginseng in Asia and Panax quinquefolium in North America has until recently taken place in the native geographical ranges of the plants. As a consequence of the potential high capital return and anticipated increases in consumer consumption, commercial cultivation of American ginseng now occurs well outside the native range of the plant in North America. In fact, the region of greatest expansion of cultivation is in the semi-arid interior region of British Columbia, Canada. Linked with this expansion is the potential domination of the ginseng industry by agricultural corporations. In the interior of British Columbia, the native deciduous forest environment of eastern North America is simulated with elevated polypropylene shade and a surface covering of straw mulch. The architecture of these environments is designed to permit maximum machinery usage and to minimize labor requirements. Further, with only a four- years growth cycle, plant densities in the gardens are high. In this hot, semi-arid environment, producers believe they have a competitive advantage over other regions in North America because of the low precipitation rates. This helps to minimize atmospheric humidity such that the conditions for fungal disease development are reduced. If soil moisture level become limited, supplemental water can be provided by irrigation. The nature of the radiation and energy balance regimes of the shade and many environments promotes high soil moisture levels. Also, the modified environment redlines soil heating. This can result in an aerial environment for the plant that is stressful and a rooting zone environment that is suloptimal. The challenge of further refining the man modified environment for enhanced plant growth and health still remains. Keywords Panax ginseng, Panax quinquefolium, cultivation, ginseng production.

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Effect of Moisture Content of Sawdust and Length to Diameter Ratio of a Hole in Flat-die Pelletizer on The Fuel Characteristics of Wood Pellets Produced with Quercus mongolica, Pinus densiflora, Pinus rigida and Larix kaempferi

  • Yang, In;Kim, Seong-ho;Han, Gyu-Seong
    • Journal of the Korean Wood Science and Technology
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    • 제45권4호
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    • pp.382-398
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    • 2017
  • This study was conducted to identify the potential of Quercus mongolica (QUM), Pinus densiflora (PID) and Pinus rigida (PIR) as a raw material for pellet production. Larix kaempferi (LAK), which has mostly been used for pellet production in Korea, was also used as a control. All specimens contained very minimal amounts of sulfur and chlorine. Ash content of LAK was the lowest, followed by PID, PIR and QUM. For the size distribution, the mass fraction between 0.42 mm and 0.25 mm was the highest in PIR. Most fuel characteristics of the produced wood pellets improved with the use of 12% moisture content (MC) particles and the increase of the ratio of length to diameter of a hole in flat-die (L/D ratio). When the MC, bulk density and durability of QUM, PID, PIR and LAK pellets was compared with the standards of the KFRI and ISO, the use of wood particles of 12% MC and flat-die with an L/D ratio of 5.00 for PID particles are suitable for high-quality pellets in the aspects of all fuel characteristics. For PIR and QUM, further work is needed to seek the optimum conditions for the production of high-quality and durable pellets.