• 제목/요약/키워드: Knowledge-Intensity

검색결과 234건 처리시간 0.026초

풍력발전시스템의 블레이드에 작용하는 극한하중에 대한 난류의 영향 연구 (A Study on the Effects of Turbulence to Ultimate Loads Acting on the Blade of Wind Turbine)

  • 현승건;김건훈
    • 한국태양에너지학회 논문집
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    • 제33권1호
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    • pp.7-14
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    • 2013
  • This study has analysed the ultimate loads acting on a wind turbine which is operating in a high turbulent flow condition because the ultimate loads are critical factors on the safe design of wind turbine. Since wind flow on the most parts of Korean mountainous are strongly influenced by complex configurations of the topography, turbulence intensity on somewhere is so stronger than an international design standard. For this reason, the characteristics of turbulent wind data collected from actual sites were analyzed and used for the ultimate load evaluation of the wind turbine. With the 270 design load cases on the international standards, the differences of ultimate loads on the wind turbine operating in the standard or high turbulent wind condition are calculated and compared for the an enhanced knowledge of the safe design basis. As are result, it is revealed the specific ultimate loads are strongly affected by the high turbulent wind conditions, thus the characteristics of turbulent flow must be considered during the design of wind turbine.

The Presence and Importance of VAM Spores in the Soil of Ginseng Gardens

  • Weber, Hans-Christian
    • 고려인삼학회:학술대회논문집
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    • 고려인삼학회 1998년도 Advances in Ginseng Research - Proceedings of the 7th International Symposium on Ginseng -
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    • pp.90-95
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    • 1998
  • Symbiotic associations between land plants and fungi have been known for more than one hundred years. Vesiculararbuscular mycorrhizas (VAM) are the most common symbiosis in flowering plants and can be recognized in almost all plant families. These fungal associations play a very important role in the growth and survival of plant species. However, with respect to the importance and intensity of the VAM, there is great variation among host species. Our knowledge of the VAM fungus-plant association in Araliaceae is very limited. After the first reports of the occurence of VAM in lateral roots of Panax species, mycorrhizal structures are now described as special structures representing the so-called Paris type. In this type, the development of new spores and vesicles is extremely low. This and the type of colonization of the fungus in Panax roots indicates on, one hand, the high intensity of the VAM and, on the other hand, a remarkable dependency for VAM in members of the Panax species. Therefore, it can be easily understood that cultivated Panax plants exhibit a significant uptake of nutrients and this leads to an extremely depleted soil at harvest. Further, the soil is nearly free of the spores of VAM fungi as they germinate each year on the newly developing Panax roots.

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파레토 및 어랑 형상모수에 의존한 수명분포를 따르는 소프트웨어 신뢰성 모형에 대한 신뢰도 특성요인 비교 연구 (A Comparison of Reliability Factors of Software Reliability Model Following Lifetime Distribution Dependent on Pareto and Erlang Shape Parameters)

  • 김희철;문송철
    • Journal of Information Technology Applications and Management
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    • 제24권2호
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    • pp.71-80
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    • 2017
  • Software reliability is one of the most elementary and important problems in software development In order to find the software failure occurrence, the instantaneous failure rate function in the Poisson process can have a constant, incremental or decreasing tendency independently of the failure time. In this study, we compared the reliability performance of the software reliability model using the parameters of Pareto life distribution with the intensity decreasing pattern and the shape parameter of Erlang life distribution with the intensity increasing and decreasing pattern in the software product testing. In order to identify the software failure environment, the parametric estimation was applied to the maximum likelihood estimation method. Therefore, in this paper, we compare and evaluate software reliability by applying software failure time data. The reliability of the Erlang and Pareto life models is shown to be higher than that of the Pareto lifetime distribution model when the shape parameter is higher and the Erlang model is more reliable when the shape parameter is higher. Through this study, the software design department will be able to help the software design by applying various life distribution and shape parameters, and providing basic knowledge using software failure analysis.

Improvement of Proton Beam Quality from the High-intensity Short Pulse Laser Interaction with a Micro-structured Target

  • Seo, Ju-Tae;Yoo, Seung-Hoon;Pae, Ki-Hong;Hahn, Sang-June
    • Journal of the Optical Society of Korea
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    • 제13권1호
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    • pp.22-27
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    • 2009
  • Target design study to improve the quality of an accelerated proton beam from the interaction of a high-intensity short pulse laser with an overdense plasma slab has been accomplished by using a two-dimensional, fully electromagnetic and relativistic particle-in-cell (PIC) simulation. The target consists of a thin core part and a thick peripheral part of equivalent plasma densities, while the ratio of the radius of the core part to the laser spot size, and the position of the peripheral part relative to the fixed core part were varied. The positive effects of this core-peripheral target structure could be expected from the knowledge of the typical target normal sheath acceleration (TNSA) mechanism in a laser-plasma interaction, and were apparently evidenced from the comparison with the case of a conventional simple planar target and the case of the transversal size reduction of the simple planar target. Improvements of the beam qualities including the collimation, the forward directionality, and the beam divergence were verified by detailed analysis of relativistic momentum, angular directionality, and the spatial density map of the accelerated protons.

Overcoming Electrical Energy Efficiency Gap in Nepal's Residential Sector

  • Thapa, Shahadev;Kim, Yun Seon
    • Asia Pacific Journal of Business Review
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    • 제3권1호
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    • pp.19-38
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    • 2018
  • The energy intensity of Nepal is economically not worthy, lacks eco-friendly and importantly not sustainable, and almost four times the average global energy intensity. Considerable efforts have been exercised to reduce the energy gap yet, it is still much to achieve. Nation priority on energy sector was envisaged with promulgation of investment friendly rules and law in hydropower and renewable technology even though, could not harness the sufficient energy. In amid of this acute energy crisis, the government launched the Nepal Energy Efficiency Programme (NEEP) with technical assistance from German International Cooperation (GIZ). Energy Efficiency (EE) practice is the most cost-effective method to reduce the supply and demand gap, reduce on greenhouse gases and pollution, and deter on import of petroleum products which finally improves on trade imbalance. This paper had proposed a framework of energy management team to promote energy efficient technologies in residential consumer. The energy management teams study the past records of energy use pattern of consumers and suggest appropriate technology for energy saving options. The paper provides some reviews of energy efficiency initiatives undertaken by the concern regulatory body which highlights the current status. The comprehensive knowledge acquired through exploratory research is implemented in this paper to identify the various barriers that domestic consumer is experiencing towards the active participation in energy efficiency program launched by the Government of Nepal.

퍼지메쉬를 이용한 3차원 균열에 대한 응력확대계수 해석 시스템 (Stress Intensity Factor Analysis System for 3D Cracks Using Fuzzy Mesh)

  • 이준성;이은철;최윤종;이양창
    • 한국지능시스템학회논문지
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    • 제18권1호
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    • pp.122-126
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    • 2008
  • 상용화된 FEM 코드와 3차원 솔리드 모델러를 통합하여 3차원 균열에 대한 자동 응력확대계수 해석 시스템을 개발하였다. 하나 또는 몇 개의 3차원 균열을 포함하는 기하학적 모델을 정의한다. 시스템에 저장된 몇 개의 절점패턴을 선택하면 자동적으로 퍼지지식 처리기법을 이용한 기하학적 모델 전 영역에 절점들이 중첩되어진다. 절점들은 생성되어지고 데로우니삼각화 법에 의한 사면체 솔리드요소가 생성되어진다. 최종적으로 완전한 유한요소 모델이 생성되어져 응력해석을 수행하게 된다. 본 논문은 몇몇 함수들을 실현시키기 위한 방법론에 대해 묘사하고 있으며 시스템의 타당성을 제시하였다.

The history of high intensity rainfall estimation methods in New Zealand and the latest High Intensity Rainfall Design System (HIRDS.V3)

  • Horrell, Graeme;Pearson, Charles
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2011년도 학술발표회
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    • pp.16-16
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    • 2011
  • Statistics of extreme rainfall play a vital role in engineering practice from the perspective of mitigation and protection of infrastructure and human life from flooding. While flood frequency assessments, based on river flood flow data are preferred, the analysis of rainfall data is often more convenient due to the finer spatial nature of rainfall recording networks, often with longer records, and potentially more easily transferable from site to site. The rainfall frequency analysis as a design tool has developed over the years in New Zealand from Seelye's daily rainfall frequency maps in 1947 to Thompson's web based tool in 2010. This paper will present a history of the development of New Zealand rainfall frequency analysis methods, and the details of the latest method, so that comparisons may in future be made with the development of Korean methods. One of the main findings in the development of methods was new knowledge on the distribution of New Zealand rainfall extremes. The High Intensity Rainfall Design System (HIRDS.V3) method (Thompson, 2011) is based upon a regional rainfall frequency analysis with the following assumptions: $\bullet$ An "index flood" rainfall regional frequency method, using the median annual maximum rainfall as the indexing variable. $\bullet$ A regional dimensionless growth curve based on the Generalised Extreme Value (GEV), and using goodness of fit test for the GEV, Gumbel (EV1), and Generalised Logistic (GLO) distributions. $\bullet$ Mapping of median annual maximum rainfall and parameters of the regional growth curves, using thin-plate smoothing splines, a $2km\times2km$ grid, L moments statistics, 10 durations from 10 minutes to 72 hours, and a maximum Average Recurrence Interval of 100 years.

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Technology Licensing Agreements from an Organizational Learning Perspective

  • Lee, JongKuk;Song, Sangyoung
    • Asia Marketing Journal
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    • 제15권3호
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    • pp.79-95
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    • 2013
  • New product innovation is a process of embodying new knowledge in a product and technology licensing is getting popular as a means to innovations and introduction of new product to the market in today's competitive global market environment. Incumbents often rely on technology licensing to access new product opportunities created by other firms. Prior research has examined various aspects of technology licensing agreements such as specific contract terms of licensing agreements, e.g., distribution of control rights, exclusivity of licensing agreements, cross-licensing, and the scope of licensing agreements. This study aims to provide answers to an important, but under-researched question: why do some incumbents initiate more licensing agreement for exploratory learning while others do it for exploitative learning along the innovation process? We attempt to extend our knowledge of licensing agreements from an organizational learning perspective. Technology licensing as a specific form of interfirm linkages can be initiated with different learning objectives along the process of new product innovation. The exploratory stages of the innovation process such as discovery or research stages involve extensive searches to create new knowledge or capabilities, whereas the exploitative stages of the innovation process such as application or test stages near the commercialization are more focused on developing specific applications or improving their efficiency or reliability. Thus, different stages of the innovation process generate different types of learning and the resulting technological resources. We examine when incumbents as licensees initiate more licensing agreements for exploratory learning objectives and when more for exploitative learning objectives, focusing on two factors that may influence a firm's formation of exploratory and exploitative licensing agreements: 1) its past radical and incremental innovation experience and 2) its internal investments in R&D and marketing. We develop and test our hypotheses regarding the relationship between a firm's radical and incremental new product experience, R&D investment intensity and marketing investment intensity, and the likelihood of engaging in exploratory and exploitive licensing agreements. Using data collected from various secondary sources (Recap database, Compustat database, and FDA website), we analyzed technology licensing agreements initiated in the biotechnology and pharmaceutical industries from 1988 to 2011. The results of this study show that incumbents initiate exploratory rather than exploitative licensing agreements when they have more radical innovation experience and when they invest in R&D activities more intensively; in contrast, they initiate exploitative rather than exploratory licensing agreements when they have more incremental innovation experience and when they invest in marketing activities more intensively. The findings of this study contribute to the licensing and interfirm cooperation studies. First, this study lays a foundation to understand the organizational learning aspect of technology licensing agreements. Second, this study sheds lights on how a firm's internal investments in R&D and marketing are linked to its tendency to initiate licensing agreements along the innovation process. Finally, the findings of this study provide important insight to managers regarding which technologies to gain via licensing agreements. This study suggests that firms need to consider their internal investments in R&D and marketing as well as their past innovation experiences when they initiate licensing agreements along the process of new product innovation.

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창조경제와 지역: 창조도시의 세가지 원천 (Creative Economy and Region: Three Sources of Creative City)

  • 문미성
    • 한국경제지리학회지
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    • 제17권4호
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    • pp.646-659
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    • 2014
  • 창조경제의 개념 및 사회적 의미에 대한 논쟁에도 불구하고 창조경제에 대한 정책적, 학술적 관심이 증대해왔다. 본 연구는 창조경제가 지역에서 실현되는 방식과 원천에 대한 탐색적 연구이다. IT혁명의 영향으로 현대인들의 네트워크는 질적 양적으로 크게 확대되어 '연결된 지식'이 창출하는 집단지성, 집단지성이 뿌리내린 '도시' '지역'은 창조 경제의 핵심 인프라가 되었다. 개인의 창조성이 발현되는 창조도시는 세 가지 바탕위에 발전한다. 첫째, 특정산업의 집적으로부터 나오는 지역의 고유성, 장소성을 기반으로 하며, 둘재, 도시의 다양한 개방적 지식정보연계망으로부터 발전한다. 셋째, 해당 지역사회의 문제를 해결하는 가치지향성과 지역에 축적된 사회적 자본으로부터 발전한다.

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국제 특허 활동과 수출 성과 간의 관계에 대한 연구 (A Study on the Relationship between International Patenting and Export Performance)

  • 문희진;최순규
    • 무역학회지
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    • 제42권3호
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    • pp.49-74
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    • 2017
  • 본 연구는 기업이 국제 특허 활동을 통해 자사 혁신의 해외 경쟁 우위와 현지 경쟁 기업들에 대한 지식을 습득하여 수출 성과를 높일 수 있지만 기업 규모와 연령에 따른 조직 학습의 비효율성 때문에 국제 특허 활동으로 인한 학습 효과는 기업 규모와 연령에 의해 약화될 수 있다는 가설들을 제시한다. 한국 제약 기업들을 대상으로 실증 분석한 결과 국제 특허 출원 집중도는 수출 집중도에 긍정적인 영향을 미쳤다. 그리고 기업 규모와 연령이 증가할수록 국제 특허 출원 집중도와 수출 집중도 간의 정의 관계는 약화되었다. 실증 분석 결과는 기업의 해외 시장에 대한 지식 습득은 해외 시장에서의 직접적인 사업 운영 외에도 다양한 경로를 통해 이루어질 수 있으며 이러한 외부 지식 학습에 있어 중소기업 및 신생기업이 상대적인 강점을 지닐 수 있음을 시사한다.

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