• Journal of Plant Biotechnology
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• 제4권3호
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• pp.109-115
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• 2002

Submerged cultures of Ganoderma lucidum, a valuable mushroom in traditional Chinese medicine, were used for production of bioactive Banoderic acids and Ganoderma polysaccharides. The significant effects of oxygen supply were demonstrated in both shake flasks and bioreactors. By changing the medium loading volume in a shake flask, a different value of initial volumetric oxygen transfer coefficient ($K_L$a) was obtained, and a higher $K_L$a value led to a higher biomass density and a higher productivity of both intracellular polysaccharide and ganoderic acid. In a stirred bioreactor, at an initial $K_L$a of 78.2 $h^{-1}$, a maximal cell concentration of 15.6 g/L by dry weight was obtained, as well as a maximal intracellular polysarcharide (IPS) production of 2.2 g/L and its maximal productivity of 220 mg/(L.d). An increase of initial $K_L$a led to a higher production and productivity of GA, and the GA production and productivity at an initial $K_L$a of 96.0 $h^{-1}$ was 1.8-fold those at an initial $K_L$a of 16.4 $h^{-1}$. The fundamental information obtained in this study may be useful for efficient large-scale production of these valuable bioactive products by the submerged cultures.

• 노동경제논집
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• 제39권2호
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• pp.113-139
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• 2016

본 연구는 한국프로야구리그(KBO)에서 활동하는 개별선수의 승리에 대한 기여도, 즉 생산성을 추정하는 모형의 구축을 목적으로 한다. 기존의 지표인 대체선수대비승수(WAR)의 단점인 계산방법의 복잡성을 해결하기 위하여 KBO 공식 홈페이지에서 제공하는 기록만을 이용한 계량모형을 구축함으로써 새로운 시즌의 기록만 대입하면 생산성을 생성할 수 있게 하였다. 또한, Scully(1974)와 Krautman(1999) 등 미국 메이저리그 선수의 가치추정모형이 소수의 기록에만 의존하였던 점을 개선하여 KBO가 발표하는 61개 기록을 모두 사용하여 현실에 적용할 수 있는 모형을 구축하였다. 2002-14년 팀기록의 패널 자료를 이용하여 득점 및 실점방정식을 추정하여 회귀분석에 기초한 대체선수대비승수를 추산하였다. 추정 결과, WAR과 상관계수가 타자는 0.869, 투수는 0.882로 나타나 두 지표가 비교적 유사한 것으로 나타났다. 추정 결과를 근거로 2014년 시즌 후 FA선수들의 계약 내용을 평가하면 비교적 생산성 추정치와 계약액수의 상관관계가 높아서 구단이 FA계약에서 합리적인 판단을 하고 있는 것으로 나타났다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 1999년도 Proceedings of International Symposium on Remote Sensing
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• pp.107-114
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• 1999

The large-scale distribution of crops Is usually determined by climate. We present the results of a climate-crop prediction based on spatial bio-physical process model approach, implemented in a GIS (Geographic Information System) environment using several regional and global agriculture-environmental databases. The model utilizes daily climate data like temperature, rainfall, solar radiation being generated stocastically by in-built model weather generator to determine the daily biomass and finally the crop yield. Crops are characterized by their specific growing period requirements, photosynthesis, respiration properties and harvesting index properties. Temperature and radiation during the growing period controls the development of each crop. The model simulates geographic/spatial distribution of climate by which a crop-growing belt can also be determined. The model takes both irrigated and non-irrigated area crop productivity into account and the potential increase in productivity by the technical means like mechanization is not considered. All the management input given at the base year 1995 was kept same for the next twenty-year changes until 2015. The simulated distributions of crops under current climatic conditions coincide largely with the current agricultural or specific crop growing regions. Simulation with assumed weather generated derived climate change scenario illustrate changes in the agricultural potential. There are large regional differences in the response across the country. The north-south and east-west regions responded differently with projected climate changes with increased and decreased productivity depending upon the crops and scenarios separately. When water was limiting or facilitating as non-irrigated and irrigated area crop-production effects of temperature rise and higher $CO_2$ levels were different depending on the crops and accordingly their production. Rise in temperature led to yield reduction in case of maize and rice whereas a gain was observed for wheat crop, doubled $CO_2$ concentration enhanced yield for all crops and their several combinations behaved differently with increase or decrease in yields. Finally, with this spatial modeling approach we succeeded in quantifying the crop productivity which may bring regional disparities under the different climatic scenarios where one region may become better off and the other may go worse off.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2002년도 학술대회지
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• pp.375-378
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• 2002

현장에서 수행되는 대부분의 공사는 다수의 공종과 다양한 협력업체가 공사를 진행해 나간다. 그러므로 투입노무자 및 자원의 관리 상 변수의 발생이 많아 공사정보관리에 어려운 점이 많다. 이러한 현장공사의 효율적인 관리를 위해서 다양한 공사정보 관리 시스템 들이 제시되고 있으나, 시공업체 중심의 시스템 관리와 협력 업체의 참여도 및 이해도 부족과 영세로 인한 적용 어려움이 문제점으로 나타나고 있다. 또한 현장공사관리에 기초자료로 제공되는 작업일보의 정보들을 수집/분석/관리하는데 상당한 시간과 인력이 소모되고, 이동시 정보손실, 수 작업에 의한 정보의 왜곡 및 신뢰성 저하 등등 다양한 문제점이 나타나고 있다. 따라서, 본 연구에서는 기존 협력업체가 작성하는 작업일보의 기능 및 문제점을 분석하고, 작업일보내의 생산성 정보의 흐름 및 생산성 향상 요인을 분석하여, 작업일보의 작성프로세스를 개선하는 것을 목적으로 하고 있다. 더 나아가, 협력업체 중심의 정보입력 및 관리를 통한 공사의 생산성을 향상시킬 수 있는 개선된 작업일보 시스템의 방향을 제시하고자 한다.

• 벤처창업연구
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• 제5권4호
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• pp.51-68
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• 2010

중형항공기 개발프로젝트에 대한 경제성분석을 생산유발효과 및 생산성제고효과로 측정하고 타 산업과 비교분석하였다. 2010년부터 7년간에 걸쳐 투입될 총 1조4,700억 원 투자로부터 나타나는 생산유발효과는 5조1,288억 원, 생산성제고효과는 651억 원으로 추정되었다. 비교대상 다섯 개 산업 중에서 생산유발효과는 선박, 자동차, 항공기, 일반목적용 기계 및 장비, 반도체의 순으로 크게 나타났고, 생산성제고효과는 선박, 항공기, 자동차, 일반 목적용 기계 및 장비, 반도체의 순으로 크게 나타났다. 국방 및 항공우주기술개발이라는 측면을 차치하고도 경제적 파급효과 측면에서 항공 산업에 대한 투자의 타당성이 큰 것으로 판단된다. 또한 우주항공기술은 우리나라의 신 성장 동력이 될 수 있는 기술 분야로 향후 수 많은 관련 벤처기업의 탄생을 가져올 수도 있다. 본 연구가 제시하는 방법을 적용하여 신기술 또는 신산업에 대한 투자분석 시에 프로젝트 단독의 경제성뿐만 아니라 거시적 관점에서의 경제적 파급효과를 고려한다면 투자의사결정에 차이가 나타날 수 있을 것이다.

• 수산해양기술연구
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• 제45권1호
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• pp.22-33
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• 2009

Ecological risk assessment(ERA), developed in Australia, can be used to estimate the risk of target, bycatch and protected species from the effects of fishing using limited data for stock assessment. In this study, we employed the ERA approach to estimate risks to tunas, billfishes, sharks, sea turtles and other species by the Korean tuna longline fishery in the Western and Central Pacific Ocean using productivity and susceptibility analyses of the ERA based on low(<1.30), medium(1.30-1.84) and high risk(>1.84). Albacore, bigeye, yellowfin, skipjack and bluefin tunas were generally evaluated in the medium risk. The susceptibility of tuna species, however, had higher risks than the productivity. Billfishes were also at medium risk, while sharks were at high risk by the tuna longline fishery. The risk of productivity was generally high, because most sharks caught by the tuna longline fishery have high longevities, i.e., over 10 years, including ovoviviparous species. Susceptibility, which is related with the selection of fishing gear, was also high, because the longline fishery has no gear modifications to prevent bycatch of protected species. Not only target tuna species were influenced by the tuna longline fishery in the Western and Central Pacific Ocean, but also nontarget species, such as pomfret, mackerels rays, sea turtle were done. Ecosystem-based fishery assessment tools, such as productivity and susceptibility analysis(PSA), have the ability to provide broad scientific advice to the policy makers and stakeholders.

• 농촌계획
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• 제19권4호
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• pp.115-123
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• 2013

Owing to increase of meteorological disasters by climate change, it needs to study of climate change which will be able to deal with adaption for basic local authorities. A case study area of Yesan have been impacted by land-use which alter natural environment demage. It has led to micro-climate change impacts in rural area, Yesan. In order to adapt to the effects, this paper estimated temperature change in productivity of fruits and conducted decline of nonpoint pollutant loadings. As the results of temperature change of effecting on growth of apple, since a rise in temperature have not increased high, therefore the apple productivity could not be influence until 2030s. While the apple productivity could be declined 14.8% in 2060s. In addition, it supposes that the productivity would be decreased 44.5% in 2090s. Furthermore, it showed that the apple maturity has become worse, because length of high temperature has dramatic increased 54.2% in 2030s, 103.2% in 2060s and 154.0% in 2060s beside 2000, respectively, compared with 2000. As results of analysing between the future rainfall characteristics and nonpoint pollutant loadings, the subject of reduction of nonpoint pollutant was efficiency when it implemented around Oga-myeon or Deoksan-myeon Dun-ri. This study classified the region more detail each Eup and Myeon after that it analysed the rural region impacts of climate change for basic local authorities. Hence, this study is able to predict adaptation of rural region impacts of climate change. Due to increase of green house gases emission, meteorological disasters could often occur in the future. Therefore, it needs follow-up studies that assess climate change of effecting on rural region.

• 품질경영학회지
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• 제48권1호
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• pp.51-68
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• 2020

Purpose: The primary objective of this research is to develop the optimal operating conditions as well as their associated design spaces for a Cryogenic Submerged Arc Welding(SAW) process by improving its quality and productivity simultaneously. Methods: In order to investigate functional relationships among quality characteristics and their associated control factors of an SAW process, a stepwise design of experiment(DoE) method is proposed in this paper. Based on the DoE results, not only a multi-dimensional design space but also a safe operating space and normal acceptable range(NAR) by integrating statistical confidence intervals were demonstrated. In addition, the optimal operating conditions within the proposed NAR can be obtained by a robust optimal design method. Results: This study provides a customized stepwise DoE method (i.e., a sequential set of DoE such as a factorial design and a central composite design) for Cryogenic SAW process and its statistical analysis results. DoE results can then provide both the main and interaction effects of input control factors and the functional relationships between the input factors and their associated output responses. Maximizing both the product quality with high impact strength and the productivity with minimum processing times simultaneously in a case study, we proposed a design space which can provide both acceptable productivity and quality levels and NARs of input control factors. In order to confirm the optimal factor settings and the proposed NARs, validation experiments were performed. Conclusion: This research may provide significant contributions and applications to many SAW problems by preparing a standardization of the functional relationship between the input factors and their associated output response. Moreover, the proposed design space based on DoE and NAR methods can simultaneously consider a number of quality characteristics including tradeoff between productivity and quality levels.

• 농업과학연구
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• 제44권3호
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• pp.400-408
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• 2017

This experiment was conducted to estimate the livestock carrying capacity per unit area of Hanwoo heifer with determine the quality of the forage by evaluating the productivity and nutritive value of spring seeding oats (Avena sative L.) according to different seeding and harvesting timings. Dry matter yields were the highest at 13.62 tons per ha when oat was seeded on March 15 and harvested on June 8 (p < 0.05), while the lowest yield of 6.29 tons per ha was obtained when seeded on February 25 and harvested on May 19 (p < 0.05). The highest crude protein yield of 1.27 tons per ha (p < 0.05) was obtained when seeded on March 5 and harvested on June 8. The total digestible nutrient yield was the highest at 7.38 tons per ha when harvested on June 8, the last harvest of the experiment (p < 0.05). In the northern part of Gyeongbuk province, spring seeding oats at the beginning of March, rather than in the middle of March, showed good annual livestock carrying capacity per unit area. According to harvest timing, the plot harvested on June 8 showed the highest livestock carrying capacity with an average of 6.53 heads (p < 0.05). In conclusion, in the northern part of Gyeongbuk province in spring, it is better to seed oat early in March and to harvest early in June to increase the livestock breeding capacity, considering dry matter productivity and feed value.

• Journal of Microbiology and Biotechnology
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• 제23권1호
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• pp.92-98
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• 2013

Microalgal cultivation using wastewater is now regarded as essential for biodiesel production, as two goals can be achieved simultaneously; that is, nutrient removal efficiency and biomass production. Therefore, this study examined the effects of carbon sources, the N:P ratio, and the hydraulic retention time (HRT) to identify the optimal conditions for nutrient removal efficiency and biomass production. The effluent from a 2nd lagoon was used to cultivate microalgae. Whereas the algal species diversity and lipid content increased with a longer HRT, the algal biomass productivity decreased. Different carbon sources also affected the algal species composition. Diatoms were dominant with an increased pH when bicarbonate was supplied. However, 2% $CO_2$ gas led to a lower pH and the dominance of filamentous green algae with a much lower biomass productivity. Among the experiments, the highest chlorophyll-a concentration and lipid productivity were obtained with the addition of phosphate up to 0.5 mg/l P, since phosphorus was in short supply compared with nitrogen. The N and P removal efficiencies were also higher with a balanced N:P ratio, based on the addition of phosphate. Thus, optimizing the N:P ratio for the dominant algae could be critical in attaining higher algal growth, lipid productivity, and nutrient removal efficiency.