• Title/Summary/Keyword: critical means

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Use of DNA-Specific Anthraquinone Dyes to Directly Reveal Cytoplasmic and Nuclear Boundaries in Live and Fixed Cells

  • Edward, Roy
    • Molecules and Cells
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    • v.27 no.4
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    • pp.391-396
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    • 2009
  • Image-based, high-content screening assays demand solutions for image segmentation and cellular compartment encoding to track critical events - for example those reported by GFP fusions within mitosis, signalling pathways and protein translocations. To meet this need, a series of nuclear/cytoplasmic discriminating probes have been developed: DRAQ5$^{TM}$ and CyTRAK Orange$^{TM}$. These are spectrally compatible with GFP reporters offering new solutions in imaging and cytometry. At their most fundamental they provide a convenient fluorescent emission signature which is spectrally separated from the commonly used reporter proteins (e.g. eGFP, YFP, mRFP) and fluorescent tags such as Alexafluor 488, fluorescein and Cy2. Additionally, they do not excite in the UV and thus avoid the complications of compound UV-autofluorescence in drug discovery whilst limiting the impact of background sample autofluorescence. They provide a convenient means of stoichiometrically labelling cell nuclei in live cells without the aid of DMSO and can equally be used for fixed cells. Further developments have permitted the simultaneous and differential labelling of both nuclear and cytoplasmic compartments in live and fixed cells to clearly render the precise location of cell boundaries which may be beneficial for quantitative expression measurements, cell-cell interactions and most recently compound in vitro toxicology testing.

Analysis of Magneto-rheological Fluid based Semi-active Squeeze Film Damper and Its Application to Unbalance Response Control of Rotor (자기유변유체를 이용한 반능동형 스퀴즈 필름 댐퍼의 해석 및 회전체 불균형 응답 제어)

  • Kim, Keun-Joo;Lee, Chong-Won
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2004.11a
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    • pp.1005-1011
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    • 2004
  • Squeeze film dampers (SFDs) have been commonly used to effectively enhance the dynamic behavior of the rotating shaft supported by rolling element bearings. However, due to the recent trends of high operating speed, high load capacity and light weight in rotating machinery, it is becoming increasingly important to change the dynamic characteristics of rotating machines in operation so that the excessive vibrations, which may occur particularly when passing through critical speeds or unstable regions, can be avoided. Semi-active type SFDs using magneto-rheological fluid (MR fluid), which responds to an applied magnetic field with a change in rheoloaical behavior, are introduced in order to find its applications to rotating machinery as an effective device attenuating unbalance responses. In this paper, a semi-active SFD using MR fluid is designed, tested and identified by means of linear analysis to investigate the capability of changing its dynamic properties such as damping and stiffness. Furthermore, the proposed device is applied to a rotor system to investigate its potential capability for vibration attenuation: an efficient method for selecting the optimal location of the proposed damper is introduced and control algorithm that could improve the unbalance response properties of a flexible rotor is also proposed.

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Fracture Behavior of Fiber Reinforced Composites under tensile and Bending Loadings (섬유강화 복합재료의 인장 및 굽힘에 의한 파괴)

  • Nam, Gi-U;Mun, Chang-Gwon
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.30 no.1
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    • pp.45-52
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    • 1994
  • The study was conducted to evaluate reliability of the longitudinal tensile properties of unidirectional carbon fiber reinforced composites. Two kinds of carbon fiber reinforced composites laminates were tested in order to examine the factors of variability and have the information concerning reliability improvement. Temperature dependence of the strength and its variability were investigated by means of testing at two kinds of temperatures. Statistical distributions of the respective mechanical properties were obtained from the tensile tests. As a result, strength of composites was directly proportional to the ultimate strain and was not proportional to the elastic modulus. The fracture behavior in bending of notched plate was studied for a composite material. The uniform bending tests of notched plates have been carried out for a wide range of notch radii. The experiment shows that the nominal stress at failure decreased with decreasing notch radius and it approaches a constant value when the notch radius is less than about 0.3mm. The critical maximum stress is governed by notch root radius alone in the case of a constant thickness of specimen.

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A Critical Approach to 'Business-Friendly' Record Management In Electronic Records Environment (전자기록 환경에서의 '업무친화적' 기록관리 방향성 분석)

  • Kim, Myoung-Hun
    • Journal of Information Management
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    • v.38 no.4
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    • pp.145-166
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    • 2007
  • This article analyzes the direction of 'business-Friendly' record management in electronic records environment which means paradigm shift in record management. In the first place, this article investigates the interrelationship of business, records and record management through natures of electronic records, and analyzes direction of purposes and roles of record management in electronic records environment. After all, this article rebuilds a significance and roles of record management in active stage, and provides theoretical bases for close relation between record management and information management in electronic records environment.

A Study on Enhancement Available Transfer Capability Using STATCOM (STATCOM을 이용한 지역간 융통전력 증대방안에 관한 연구)

  • Kim Yang il;Jeung Sung Won;Shin Woon Yong;Kwak Sang Un;Kim Jae Hyeon
    • Proceedings of the KIEE Conference
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    • summer
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    • pp.156-158
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    • 2004
  • Recently electrical industry has been rapidly restructured by deregulation in the developed countries. The voltage stability problem of a power system is associated with a rapid voltage drop due to heavy load and it occurs because of inadequate reactive power supply at some critical buses. More effective power system control means for line flow and bus voltage are required for applying FACTS. In this paper Jacobian method used to study on the voltage stability, The Jacobian method is to check the eigenvalue of the load flow Jacobian matrix. If the power system is unstable, one of the eigenvalues, at leasL has crossed the imaginary axis. This paper demonstrate enhancement of ATC by application of STATCOM at WSCC 9-bus system.

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Experimental study of Kaiser effect under cyclic compression and tension tests

  • Chen, Yulong;Irfan, Muhammad
    • Geomechanics and Engineering
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    • v.14 no.2
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    • pp.203-209
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    • 2018
  • Reliable estimation of compressive as well as tensile in-situ stresses is critical in the design and analysis of underground structures and openings in rocks. Kaiser effect technique, which uses acoustic emission from rock specimens under cyclic load, is well established for the estimation of in-situ compressive stresses. This paper investigates the Kaiser effect on marble specimens under cyclic uniaxial compressive as well as cyclic uniaxial tensile conditions. The tensile behavior was studied by means of Brazilian tests. Each specimen was tested by applying the load in four loading cycles having magnitudes of 40%, 60%, 80% and 100% of the peak stress. The experimental results confirm the presence of Kaiser effect in marble specimens under both compressive and tensile loading conditions. Kaiser effect was found to be more dominant in the first two loading cycles and started disappearing as the applied stress approached the peak stress, where felicity effect became dominant instead. This behavior was observed to be consistent under both compressive and tensile loading conditions and can be applied for the estimation of in-situ rock stresses as a function of peak rock stress. At a micromechanical level, Kaiser effect is evident when the pre-existing stress is smaller than the crack damage stress and ambiguous when pre-existing stress exceeds the crack damage stress. Upon reaching the crack damage stress, the cracks begin to propagate and coalesce in an unstable manner. Hence acoustic emission observations through Kaiser effect analysis can help to estimate the crack damage stresses reliably thereby improving the efficiency of design parameters.

Struggle for Social Recognition in Labour Movement (인정투쟁: 한국노동운동과 경계에 선 사람들)

  • Yoo, Bum-Sang
    • Korean Journal of Labor Studies
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    • v.23 no.1
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    • pp.165-195
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    • 2017
  • This paper deals with 'men facing limits of lives' from a perspective of struggle for social recognition. Men facing limits of lives in this paper indicates activists who have dedicated to labor movements since 1970s, and struggle for social recognition means to fight to acquire recognition in terms of love, rights and values, from members of societies. This paper analyzes the process of their failure and frustration in pursuing passion for recognition. They formed democratic labor unions, as an effort for recognition, and this led to foundation of progressive parties. Nonetheless, they are standing on a crossroad between lethargic and depression, while they are pursuing reformation and revolution. Why is their passion cooled down and depression aggravated? This paper argues various rifts both in internal and external realms of labor activists as critical factor of the failure, and suggests communication to heal the rifts as an alternative.

Resiliency Assessment of Sarasota Bay Watershed, Florida

  • Lee, Hye-Kyung
    • Journal of KIBIM
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    • v.9 no.1
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    • pp.32-41
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    • 2019
  • As population in Sarasota and Manatee Counties, Florida in the United States is projected to increase, land use changes from land development happen continuously. The more land development means the more impervious surfaces and stormwater runoff to Sarasota Bay, which causes critical impact on the resiliency of the ecosystem. In order to decrease its impact on water quality and the ecosystem function of Sarasota Bay, it is important to assess the resilient status of communities that create negative impacts on the ecosystem. Three types of guiding principles of resiliency for Sarasota Bay watershed are suggested. To assess resiliency status, three indexes - vulnerability index, socio-economic index, and ecological index are developed and analyzed by using geographic information system for each census tract in the two counties. Since each indicator for vulnerability index, socio-economic index, and ecological index is measured with different metrics, statistical standardizing method - distance from the best and worst performers is used for this study to directly compare and combine them all to show total resilience score for each census tract. Also, the ten most and the ten least scores for the total resilience index scores are spatially distributed for better understanding which census tracts are most or least resilient. As Sarasota Watershed boundary is also overlaid, it is easy to understand how each census tract attains its resilience and how each census tract impacts to Sarasota Bay ecosystem. Based on results of the resiliency assessment several recommendations, guidelines, or policies for attaining or enhancing resiliency are suggested.

A Reliability Analysis of a Guyed Tower (Guyed Tower의 신뢰성 해석)

  • Tae-B.,Ha;Hang-S.,Choi
    • Bulletin of the Society of Naval Architects of Korea
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    • v.24 no.2
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    • pp.29-35
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    • 1987
  • As offshore activities move into deeper ocean, conventional fixed-base platforms drastically increase in size and cost, One of alternatives available is a guyed tower, in which environmental loads are supported by guylines instead of structural members. The guying system of the guyed tower is designed on one hand to be stiff enough to limit the structural displacement in normal operations, but on the other hand to be soft enough to permit large slow sways during the presence of design-level storms. This compliancy provides an efficient means of withstanding harsh environment so that the disproportionate increase in size of deep water platforms can be kept to a rational limit. Novel configurations contain always some degrees of potential risks mainly due to the lack of experience. The most critical hazard inherent to a guyed tower may be the pullout of anchor piles. Once it happens, the guyline fails to function and it may eventually lead to the total collapse of the system. It is the aim of this paper to discuss and quantify the anchor-pullout risk of a guyed tower. A stochastic analysis is made for evaluating the first-upcrossing probability of the tension acting on anchor piles over the uplift capacity. Nonlinearities involved in the mooring stiffness and hydrodynamics are taken into account by using time-domain analysis. A simplified two dimensional dynamic model is developed to exemplify the underlying concept. Real hurricane data in the Gulf of Mexico spanning over 70 years are incorporated in a numerical example of which result clearly indicates highly potential risk of anchor pullout.

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A Framework of User Authentication for Financial Transaction based Multi-Biometrics in Mobile Environments (모바일 환경에서 다중 바이오인식 기반의 금융 거래를 위한 사용자 인증 프레임워크)

  • Han, Seung-Jin
    • Journal of the Korea Society of Computer and Information
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    • v.20 no.1
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    • pp.143-151
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    • 2015
  • Biometric technology has been proposed as a new means to replace conventional PIN or password because it is hard to be lost and has the low possibility of illegal use. However, unlike a PIN, password, and personal information there is no way to modify the exposure if it is exposed and used illegally. Therefore, the existing single modality with single biometrics is critical when it expose. However in this paper, we use a multi-modality and multi-biometrics to authenticate between users and TTP or between users and financial institutions. Thereby, we propose a more reliable method and compared this paper with existed methods about security and performance in this paper.