• Title/Summary/Keyword: Attracting

Search Result 1,699, Processing Time 0.029 seconds

A Study on Dimensional Stability and Thermal Performance of Superheated Steam Treated and Thermal Compressed Wood

  • Chung, Hyunwoo;Han, Yeonjung;Park, Jun-Ho;Chang, Yoon-Seong;Park, Yonggun;Yang, Sang-Yun;Yeo, Hwanmyeong
    • Journal of the Korean Wood Science and Technology
    • /
    • v.44 no.2
    • /
    • pp.184-190
    • /
    • 2016
  • Recently, wood is attracting attention as green building interior decoration material. When wood is used as building interior decoration material, excellent dimensional stability and thermal performance is required. In this study, superheated steam treatment process and thermal compression process were applied to flat sawn Pinus koraiensis wood panel in order to improve dimensional stability and thermal performance. According to results of this study, superheated steam treatment process and thermal compression process improve thermal performance and dimensional stability of wood, especially in tangential direction. The spring back in radial direction reduces the effect of thermal compression on dimensional stability of wood in radial direction.

A Study of Natural Frequency in Steel Wind Turbine Tower according to the RNA Model (강재 풍력 터빈 타워의 상부구조 모델링 방법에 따른 고유진동수 특성에 대한 고찰)

  • Lee, Yun-Woo;Choi, Jun-Ho;Kang, Sung-Yong;Kang, Young-Jong
    • Journal of the Korean Society for Advanced Composite Structures
    • /
    • v.5 no.3
    • /
    • pp.37-42
    • /
    • 2014
  • Wind turbine tower has a very important role in wind turbine system as one of the renewable energy that has been attracting attention worldwide recently. Due to the growth of wind power market, advance and development of offshore wind system and getting huger capacity is inevitable. As a result, the vibration is generated at wind turbine tower by receiving constantly dynamic loads such as wind load and wave load. Among these dynamic loads, the mechanical load caused by the rotation of the blade is able to make relatively periodic load to the wind turbine tower. So natural frequency of the wind turbine tower should be designed to avoid the rotation frequency of the rotor according to the design criteria to avoid resonance. Currently research of the wind turbine tower, the precise research does not be carried out because of simplifying the structure of the other upper and lower. In this study, the effect of blade modeling differences are to be analyzed in natural frequency of wind turbine tower.

Study on fracture behavior of polypropylene fiber reinforced concrete with bending beam test and digital speckle method

  • Cao, Peng;Feng, Decheng;Zhou, Changjun;Zuo, Wenxin
    • Computers and Concrete
    • /
    • v.14 no.5
    • /
    • pp.527-546
    • /
    • 2014
  • Portland cement concrete, which has higher strength and stiffness than asphalt concrete, has been widely applied on pavements. However, the brittle fracture characteristic of cement concrete restricts its application in highway pavement construction. Since the polypropylene fiber can improve the fracture toughness of cement concrete, Polypropylene Fiber-Reinforced Concrete (PFRC) is attracting more and more attention in civil engineering. In order to study the effect of polypropylene fiber on the generation and evolution process of the local deformation band in concrete, a series of three-point bending tests were performed using the new technology of the digital speckle correlation method for FRC notched beams with different volumetric contents of polypropylene fiber. The modified Double-K model was utilized for the first time to calculate the stress intensity factors of instability and crack initiation of fiber-reinforced concrete beams. The results indicate that the polypropylene fiber can enhance the fracture toughness. Based on the modified Double-K fracture theory, the maximum fracture energy of concrete with 3.2% fiber (in volume) is 47 times higher than the plain concrete. No effort of fiber content on the strength of the concrete was found. Meanwhile to balance the strength and resistant fracture toughness, concrete with 1.6% fiber is recommended to be applied in pavement construction.

Expression of Chemokine and Tumor Necrosis Factor Alpha Genes in Murine Peritoneal Macrophages Infected with Orientia tsutsugamushi

  • Koh, Young-Sang
    • Journal of Microbiology
    • /
    • v.39 no.3
    • /
    • pp.186-194
    • /
    • 2001
  • Scrub typhus, caused by Orientia tsutsugamushi infection, is clinically and histopathologically characterized by local as well as systemic inflammatory reactions, indicating that orientiae induce mechanisms that amplify the inflammatory response. To reveal underlying mechanisms of chemoattraction and activation of responding leukocytes, expression of chemokine and tumor necrosis factor alpha (TNF-$\alpha$) genes in murine peritoneal macrophages after infection with the obligate intracellular bacterium Ο.tsutsugamushi was investigated. The genes that were unregulated included macrophage inflammatory proteins l$\alpha$/$\beta$(MIP-l$\alpha$/$\beta$), MIP-2, monocyte chemoattractant protein 1(MCP-1), RANTES (regulated upon activation, normal T-cell expressed and secreted), gamma-interferon-inducible protein 10(IP-10) and TNF-$\alpha$. Peak expression of these chemokines and TNF-$\alpha$ was observed between 1 and 3 h after infection. These responses returned to or approached baseline preinfection levels 6 h after challenge. Semiquantitative reverse transcription (RT)-PCR analysis revealed dramatic Increases during infection in the steady-state levels of mRNA ceding for the inhibitory subunit of NF-kB (IkB$\alpha$), whose transcription is enhanced by binding of NF-kB within the IkB$\alpha$promoter region. Thus, Ο. tsutsugamushi appears to be a stung inducer of chemokines and TNF-$\alpha$ which may significantly contribute to inflammation and tissue damage observed in scrub typhus by attracting and activating phagocytic leukocytes.

  • PDF

A Individualized Reasoning Strategy using Learner's Cognitive Union (학습자 인지 구조체를 이용한 추론의 개별화 전략)

  • Kim, Yong-Beom;Kim, Yungsik
    • The Journal of Korean Association of Computer Education
    • /
    • v.9 no.5
    • /
    • pp.31-39
    • /
    • 2006
  • The change into the knowledge based information society requires a transformation of educational paradigm. Accordingly, intelligent learning and distance education are attracting a fair amount of attention. To apply the instructional learning method in this field, we need to consider a individualization of learning, as it were, abstraction of fact and path through learning, which is based on learner's traits, this focus entails a argument for individualized reasoning strategy. Therefore, in this paper, we design a learner's cognitive union, which is based on X-Neuronet(eXtended Neuronet), represent learner's hierarchical knowledge is able to self-learn, and grows adaptive union by proprietor. Additionally, we propose a individualized reasoning strategy, which relies upon learner's cognitive union, and verify the validity.

  • PDF

The Activation of Transferable Skill of Advanced S & T (Science & Technology) Manpower with the Global HRD Convergence Research

  • Lim, In-Jong;Lee, Jeong-Hwan;Lee, Chunsu
    • East Asian Journal of Business Economics (EAJBE)
    • /
    • v.7 no.2
    • /
    • pp.11-20
    • /
    • 2019
  • Purposes - This study propose the following 4 methods to establish Global HRD system focusing on transferable skill which is attracting attention as future science and technology Manpower. The activation of convergence research creates new industries in the era of 4th industrial revolution. Research design and methodology -This study was conducted by using research methods and expert interviews focused on document analysis. This study also reflects trends through books and materials that cover the latest issues such as the Fourth Industrial Revolution. Results - 4 Things are reflecting the policies of S&T Manpower and securing execution capability, developing competence-based transferable skill model, enhancing science and technology convergence R&D and performance capability, and developing customized HRD program. Conclusions - Transferable skills will contribute to strengthen the national competitiveness of science and technology in the long term by establishing the foundation of technological innovation that can create new industries and secure future growth power in the 4th industrial revolution era. Practically, it was suggested that science and technology professionals should be able to refer to the HRD program design and HRD program design by suggesting the view of transferable skill and the activation plan reflecting the insight.

Experiences as Consumers: In-Depth Interview of Thai Students Studying in Korea

  • Cheon, Hye-Jung;Poraksa, Sirin
    • International Journal of Human Ecology
    • /
    • v.12 no.1
    • /
    • pp.75-85
    • /
    • 2011
  • This study aims to understand the experiences as consumers of Thai students studying in Korea. "Study Korea Project" which is a drive to globalize local universities by attracting more oversea students as a pull factor, and economic growth, values on education and Hallyu as push factors contribute to the increase the number of Thai students in Korea. In order to understand the experiences of Thai students as consumers studying in Korea, individual interviews were conducted. A total of 5 participants were asked about meaning of consumption in everyday life in Korea or any changes in consumption behavior compared to living in Thai. Three themes were identified through wholistic and selective approaches. First, all participants in the study said that they were surprised because of high living expense in Korea. Consequently, survival itself is too much for them and they have become more conscious of prices of goods. Secondly, since most participants in this study can control their own budget, they feel some degree of freedom and power of control of their own lives. This experience may help them to accomplish their developmental tasks during the transition to adulthood. Thirdly, they are easily imbued with Korean consumer culture. It causes various conflicts between buying and not-buying or friends gathering and saving money. Sometimes it makes them in stuck excessive consumption and financial problems. For a deeper understanding of oversea students' lives in Korea as consumers, further studies should take into consideration of not only their culture of origins, but also misconceptions that have accumulated around these students.

A Study on Risk Evaluation Method of Ground Subsidence around Sewer (하수관로 주변 도로함몰 위험도 평가 방법에 관한 연구)

  • Kim, Jinyoung;Choi, Changho
    • Journal of the Korean GEO-environmental Society
    • /
    • v.19 no.7
    • /
    • pp.13-18
    • /
    • 2018
  • Recently, road subsidence has been increasing in urban areas, threatening the safety of citizens. In the lower part of the road, various road facilities such as water supply and drainage pipelines and telecommunication facilities are buried, and the deterioration of the facilities causes the road subsidence. In particular, in the case of old sewer pipes which are attracting attention as a main cause of road subsidence, the management of sewer pipe replacement, repair and reinforcement is being performed depending on the burial year. Therefore, in this study, we tried to suggest a reliable road subsidence risk assessment method considering various sewer specifications and surrounding environment information and CCTV exploration result and GPR exploration result.

Application of Carbon Nanotubes in Displays

  • Feng, T.;Sun, Z.;Zhang, Z.J.;Lin, L.F.;Ding, Hui.;Chen, Y.W.;Pan, L.K.
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2008.10a
    • /
    • pp.1529-1531
    • /
    • 2008
  • Since the discovery over a decade ago, carbon nanotubes (CNTs) have been attracting considerable attentions both from scientists and engineers. Because of the excellent field emission properties, such as high aspect ratio, extremely small diameter, and high emission current, CNTs become a potential candidate as field emitter for field emission display (FED) and lighting (FEL) as backlight for LCD. Due to the exceptional physical properties, such as superior thermal and electrical conductivities, as well as high stiffness and strength, the CNT-based composites can be as light-weight heat-sink or thermal spreader materials used for power electronic devices, such as power LED for general illumination. The CNTs for above applications will be reviewed, and related materials and devices will be demonstrated in this paper.

  • PDF

A Study on Calculating the Fee Range of Broadcasting Contents : Focus on IPTV

  • Shin, Minsoo;Kil, Jinho;Bae, Seonghoon
    • Journal of Information Technology Applications and Management
    • /
    • v.22 no.2
    • /
    • pp.43-70
    • /
    • 2015
  • Concerns have been growing about whether domestic internet protocol television (IPTV) can establish a solid foothold in the pay TV market, largely because of the lack of IPTV-only content and service differentiation. It has been difficult for IPTV providers to attract valuable PPs (program providers) to strengthen their positions, and IPTV providers have invested much money into procuring content. To survive this difficult situation, IPTV providers need to reappraise their profit sharing methods and content distribution structure to facilitate the expansion of their subscriber base. This can be done by attracting valuable PPs to IPTV providers and securing extra revenue by distributing more content for their PP partners. The IPTV industry has a different structure and value chain from the digital cable industry. Moreover, profit sharing schemes among participants in the IPTV industry are complicated. Thus it is essential to analyze the criteria for profit sharing, the selection of attributes in profit sharing, and their cause-effect relationship in developing fair pricing for broadcast content in the IPTV industry. This study introduces the attributes that need to be considered for the pricing of content and profit sharing among IPTV providers and PPs. In addition, this study uses system dynamics to analyze the relationship among those attributes along with additional associated factors for the pricing of content.