• Title/Summary/Keyword: Micro-environments

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Influence of flexural loading on chloride ingress in concrete subjected to cyclic drying-wetting condition

  • Ye, Hailong;Fu, Chuanqing;Jin, Nanguo;Jin, Xianyu
    • Computers and Concrete
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    • v.15 no.2
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    • pp.183-198
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    • 2015
  • Chloride ingress implies a complex interaction between physical and chemical process, in which heat, moisture and chloride ions transport through concrete cover. Meanwhile, reinforced concrete structure itself undergoes evolution due to variation in temperature, relative humidity and creep effects, which can potentially change the deformation and trigger some micro-cracks in concrete. In addition, all of these process show time-dependent performance with complex interaction between structures and environments. In the present work, a time-dependent behavior of chloride transport in reinforced concrete beam subjected to flexural load is proposed based on the well-known section fiber model. The strain state varies because of stress redistribution caused by the interaction between environment and structure, mainly dominated by thermal stresses and shrinkage stress and creep. Finally, in order to clear the influence of strain state on the chloride diffusivity, experiment test were carried out and a power function used to describe this influence is proposed.

pH Response Pathways in Fungi: Adapting to Host-derived and Environmental Signals

  • Selvig, Kyla;Alspaugh, J. Andrew
    • Mycobiology
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    • v.39 no.4
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    • pp.249-256
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    • 2011
  • Microorganisms are significantly affected when the ambient pH of their environment changes. They must therefore be able to sense and respond to these changes in order to survive. Previous investigators have studied various fungal species to define conserved pH-responsive signaling pathways. One of these pathways, known as the Pal/Rim pathway, is activated in response to alkaline pH signals, ultimately targeting the PacC/Rim101 transcription factor. Although the central signaling components are conserved among divergent filamentous and yeast-like fungi, there is some degree of signaling specificity between fungal species. This specificity exists primarily in the downstream transcriptional targets of this pathway, likely allowing differential adaptation to species-specific environmental niches. In this review, the role of the Pal/Rim pathway in fungal pH response is discussed. Also highlighted are functional differences present in this pathway among human fungal pathogens, differences that allow these specialized microorganisms to survive in the various micro-environments of the infected human host.

Natural Convection for Air-Layer between Body Skin and Clothing with Considering Coefficient of Permeability (투과계수를 고려한 의복과 인체 사이의 공기층에서 자연대류 특성)

  • 지명국;배강렬;정효민;정한식;추미선
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.13 no.12
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    • pp.1282-1287
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    • 2001
  • This study presents the numerical analysis of natural convection of a micro- environments with air permeability in the clothing air-layer. As a numerical model the clothing air layer of shoulder and arm were adopted. Finite volume method for two-dimensional laminar flow was used for the analysis of flow and thermal characteristics of velocity, temperature and concentration in the air layer between body and clothing. As temperature boundary conditions, a body skin has a high temperature with $34^{\circ}C$ and the environmental temperatures are 5, 15 and $25^{\circ}C$ for various permeability coefficients. The distributions of concentration, temperature and velocity are shown that two large cells form at horizontal and vertical air layer, respectively. As the temperature difference between body skin and environment decreases, the heat transfer is decreased rapidly.

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A Comparative Management Study Focused on Manufacturer (제조업경영의 국제비교에 관한 소고)

  • 정태영
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.8 no.12
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    • pp.79-87
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    • 1985
  • Environmental approach places the focus on a cause-and-effect relationship between the external environments and the internal business conditions. But that approach is an attempt to describe the characteristics of environmental constraints. W.J. Abernathy, K.B. Clark, and A.M. Kantrow attribute the Japanese carmaker's success to superiority in the manufacturing plant, especially in their process systems and work force management. They provide a paradigm for discussions of manufacturing competitiveness comparison. The structure of the paradigm has two main distinctions. The first is the division between analysis and prescription of a macro sort and those of a micro sort, the second is the division between analysis and prescription based on hardware and those based on software.

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Functional Definitions in DGS Environments. (DGS 동적 기하에서의 새로운 함수적 관점의 정의)

  • 김화경;조한혁
    • The Mathematical Education
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    • v.43 no.2
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    • pp.177-186
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    • 2004
  • In this paper, we introduce new functional definitions for school geometry based on DGS (dynamic geometry system) teaching-learning environment. For the vertices forming a geometric figure, we first consider the relationship between the independent vertices and dependent vertices, and using this relationship and educational considerations in DGS, we introduce functional definitions for the geometric figures in terms of its independent vertices. For this purpose, we design a new DGS called JavaMAL MicroWorld. Based on the needs of new definitions in DGS environment for the student's construction activities in learning geometry, we also design a new DGS based geometry curriculum in which the definitions of the school geometry are newly defined and reconnected in a new way. Using these funct onal definitions, we have taught the new geometry contents emphasizing the sequential expressions for the student's geometric activities.

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Development of Ubiquitous based Digital Switchgear Prototype for Home Automation (주택 자동화를 위한 유비쿼터스 기반의 디지털 분전반 프로토타입 개발)

  • Ko, Yun-Seok;Yun, Tae-Min;Yun, Seok-Ryul
    • Proceedings of the KIEE Conference
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    • 2007.07a
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    • pp.555-556
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    • 2007
  • This paper proposes a new concept's IDSFHA(Intelligent Digital Switchgear For Home Automation) which can obtain the safety, the reliability and the easy to correspond to the request of the general electric customer or electric power company under the ubiquitous-based home automation environments The IDSFHA is designed by analyzing their requirement functions, a 32-bit micro processor is adopted as main controller to support efficiently the designed functions. The single phase power IC(ADE7753) is utilized to collect the electric power information, and makes it possible to communicate as internet among the IDSFHA and their using the ethernet convertor. In the proposed IDSFHA, the several functions are implemented such as the earth leakage level display and waveform transmitting, the electric power using fee display, voltage management, load management and load control function. Finally, the prototype of the IDSFHA is made experimently based on the designed results.

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MOBILE FRAMEWORK FOR INTEGRATED 4S DATA

  • Oh, Byoung-Woo;Kim, Mi-Jeong;Lee, Eun-Kyu;Kim, Min-Soo
    • Proceedings of the KSRS Conference
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    • 2002.10a
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    • pp.838-843
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    • 2002
  • Recently, PDA and cellular phone with color LCD have been widely used in various fields by high efficiency and micro miniaturization technology. According to maturity of these mobile environments, user request about mobile application field is increased. Mobile applications provide various information which is concerned with user's position through cable and wireless transmission. This paper discusses the issues related to the mobile framework for integrated 4S data. The integrated 4S data mean spatial data fusion on GIS, SIIS, ITS, and GNSS. The mobile framework provides not only spatial data but also location services such as reverse geocoding, directory service, etc. It consists of client subsystem, service provider, and data provider.

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Authenticated Binding Update Protocol for Micro and Pico Cell Environments (마이크로 및 피코 셀 환경을 위한 인증된 바인딩 갱신 프로토콜)

  • Koo, Jung-Sook;Koo, Jung-Doo;Lee, Gi-Sung
    • Proceedings of the KAIS Fall Conference
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    • 2007.11a
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    • pp.205-208
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    • 2007
  • 본 논문에서 마이크로 및 피코 셀 환경에 적합한 인증된 바인딩 업데이트 프로토콜을 제안한다. 제안하는 프로토콜은 CGA (Cryptographically Generated Address) 기반의 티켓 방식을 이용한다. 이 방식은 호스트의 공개키와 서브넷 프리픽스를 이용하여 생성한다. 또한 초기통신 시에 대응노드는 이동 노드에게 홈 에이전트를 통한 티켓을 발행한다. 이는 이동노드와 대응노드 간에 직접 바인딩 갱신을 할 수 있도록 도와준다. 또한 대응노드는 티켓 확인을 통한 이동노드를 인증하고 바인딩 업데이트를 안전하게 수행한다. 몇 가지 공격 시나리오를 통한 프로토콜의 안전성을 분석한다. 마지막으로 결론 및 향후 연구 방향에 대해서 제시한다.

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Roles of non-coding RNAs in intercellular crosstalk in cardiovascular diseases

  • Yeong-Hwan Lim;Young-Kook Kim
    • The Korean Journal of Physiology and Pharmacology
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    • v.27 no.4
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    • pp.289-298
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    • 2023
  • Complex diseases including cardiovascular disease are caused by a combination of the alternation of many genes and the influence of environments. Recently, non-coding RNAs (ncRNAs) have been shown to be involved in diverse diseases, and the functions of various ncRNAs have been reported. Many researchers have elucidated the mechanisms of action of these ncRNAs at the cellular level prior to in vivo and clinical studies of the diseases. Due to the characteristics of complex diseases involving intercellular crosstalk, it is important to study communication between multiple cells. However, there is a lack of literature summarizing and discussing studies of ncRNAs involved in intercellular crosstalk in cardiovascular diseases. Therefore, this review summarizes recent discoveries in the functional mechanisms of intercellular crosstalk involving ncRNAs, including microRNAs, long non-coding RNAs, and circular RNAs. In addition, the pathophysiological role of ncRNAs in this communication is extensively discussed in various cardiovascular diseases.

A New Secure Multicast Protocol in Micro-Mobility Environments using Secure Group Key (마이크로 모빌리티 환경에서 보안 그룹키를 이용한 안전한 멀티캐스트 프로토콜)

  • Kang, Ho-Seok;Shim, Young-Chul
    • The KIPS Transactions:PartC
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    • v.15C no.6
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    • pp.573-586
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    • 2008
  • The improved performance and miniaturization of computer and the improvement of wireless communication technology have enabled the emergence of many high quality services. Among them multicast services are receiving much attention and their usage is increasing due to the increase of Internet multimedia services such as video conference, multimedia stream, internet TV, etc. Security plays an important role in mobile multicast services. In this paper, we proposed a secure multicast protocol for a hierarchical micro-mobility environment. The proposed secure multicast protocol provides security services such as authentication, access control, confidentiality and integrity using mechanisms including symmetric/asymmetric key crypto-algorithms and capabilities. To provide forward/backward secrecy and scalability, we used sub-group keys based on the hierarchical micro-mobility environment. With this security services, it is possible to guard against all kinds of security attacks performed by illegal mobile nodes. Attacks executed by internal nodes can be thwarted except those attacks which delete packet or cause network resources to be wasted. We used simulator to measure the performance of proposed protocol. As a result, the simulation showed that effect of these security mechanisms on the multicast protocol was not too high.