• Title/Summary/Keyword: Life Force

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Cellular machinery for sensing mechanical force

  • Lim, Chul-Gyun;Jang, Jiyoung;Kim, Chungho
    • BMB Reports
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    • v.51 no.12
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    • pp.623-629
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    • 2018
  • For mechanical force to induce changes in cellular behaviors, two main processes are inevitable; perception of the force and response to it. Perception of mechanical force by cells, or mechanosensing, requires mechanical force-induced conformational changes in mechanosensors. For this, at least one end of the mechanosensors should be anchored to relatively fixed structures, such as extracellular matrices or the cytoskeletons, while the other end should be pulled along the direction of the mechanical force. Alternatively, mechanosensors may be positioned in lipid bilayers, so that conformational changes in the embedded sensors can be induced by mechanical force-driven tension in the lipid bilayer. Responses to mechanical force by cells, or mechanotransduction, require translation of such mechanical force-induced conformational changes into biochemical signaling. For this, protein-protein interactions or enzymatic activities of mechanosensors should be modulated in response to force-induced structural changes. In the last decade, several molecules that met the required criteria of mechanosensors have been identified and proven to directly sense mechanical force. The present review introduces examples of such mechanosensors and summarizes their mechanisms of action.

Evaluation of the Aging Life of the Rubber Pad in Power Window Switch

  • Kang, Yong Kyu;Choi, Byung Ik;Woo, Chang Su;Kim, Wan Doo
    • Elastomers and Composites
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    • v.54 no.4
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    • pp.351-358
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    • 2019
  • To evaluate the aging of a rubber pad in power window switch which is the part of a vehicle, the accelerated thermal aging test of rubber pad material is performed. Finite element analysis was performed using the nonlinear material constants of the rubber pad to calculate the operating force, and the Arrhenius relationship was derived from the aging temperature and time. The aging test was performed at 150, 180, 210, or 240 ℃ for 1 to 60 days. When the operating force of the rubber pad is changed by 10% from the initial value, the service life is expected to be 113 years, which is much longer than the life of the vehicle. This indicates that the aging life of the rubber pad is sufficiently safe and the operating force of the rubber pad during the life of the vehicle (20 years) was decreased by approximately 8.4%. By examining the correlation between the shear elastic modulus and operating force calculated from finite element analysis under each aging test condition, the changes in the operating force of the rubber pad and the shear elastic modulus showed good linear relationship. The aging life could be predicted by the change in shear elastic modulus and a process for predicting the aging life of automotive power window switch rubber pad parts is described herein.

Study of the Hermeneutical Phenomenon regarding the Meaning of the Driving Force of Life Experienced by the Elderly (노인이 경험하는 삶의 원동력 의미에 관한 해석학적 현상학 연구)

  • Han, SukJung;Kang, KyungAh;Lim, YoungSook
    • Journal of Korean Public Health Nursing
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    • v.33 no.1
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    • pp.109-122
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    • 2019
  • Purpose: The purpose of this study was to understand the meaning of the driving force of life experienced by the elderly and the realistic structure of their experience. Methods: The research question was "What is the essential meaning of the driving force experienced by the elderly?". Data were collected from individual in-depth interviews between March, 2017 and May, 2017 and analyzed using Van Manen's hermeneutic phenomenological methodology to identify the essential themes of their experience. Results: Through the analysis process, 22 themes and 14 essential themes were derived. The 14 essential themes of the driving force of the life of elderly were as follows: 'Memories from the past', 'Poverty to escape', 'Hand down family's heritage', 'A body bound by marriage', 'A body necessary for old age', 'A dignified body even if they grow older', 'A body that does not want to fall', 'A fruit of my life', 'Mature real love', 'Unchanging fraternity', 'Extended family', 'An old friend with whom share my heart', 'Satisfied with the situation', and 'Expanding the breadth of life'. Conclusion: Nursing programs that assess the driving force of life supporting the elderly and supports the driving force of such a life should be developed.

Geological Study of Crave Fengsui (지질학으로 본 음택풍수)

  • 김용학
    • Journal of the Korean Professional Engineers Association
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    • v.34 no.2
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    • pp.62-67
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    • 2001
  • The grave Fengsui is a systematic life science, explained by the life energy of Yin-yang and Its five elements. The life energy of Yin-yang and its five elements, though Invisible and thus difficult to apply, Is easily conceived of as the magnetic force. When the life energy of the grave Fengsui is not understood as ambiguous moving force but as magnetic force, It is possible to open up a new field of Fengsui life culture.

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Comparison analysis of psychological and biochemical indices of chronic life stress

  • Kim, Dongsoo;Park, Se-kwon;Chung, Yeon-Soo;Moon, Soo-Jong
    • Proceedings of the Korean Society of Toxicology Conference
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    • 2003.10b
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    • pp.162-162
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    • 2003
  • The psychological and biochemical stress responses of healthy men and women were measured under the normal situation. Experimental subjects, who were cadets of the Korea Air Force Academy, were selected by the random sampling. Quantitative scaling of the psychological stress was obtained by life stress test(Cheon et al, 2000) and Minnesota Multiphasic Personality Inventory(MMPI).(omitted)

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Evaluation of Wheel Life by Grinding Ratio and Static Force

  • Kwak, Jae-Seob;Ha, Man-Kyung
    • Journal of Mechanical Science and Technology
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    • v.16 no.9
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    • pp.1072-1077
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    • 2002
  • A degree of sharpness in wheel grains affects the surface roughness and dimensional accuracy in the grinding process. If a wheel with dull grains is used, the grinding force is increased and the surface roughness is deteriorated. In ovder to produce a precision component economically, the magnitude of the wear amount in the grinding wheel has to be limited. In this study, experimental evaluation of a wheel life varying with the grinding ratio and static grinding force was conducted. The grinding ratio and grinding force were measured to seek the grinding performance of the WA wheel. The relationship between the grinding ratio and static grinding force was presented.

The relation of TiN coating condition of end-mill and cutting force increase rate (엔드밀의 TiN 코팅조건과 절삭력 증가율과의 관계)

  • 최석우;이위로;최광진;백영남
    • Journal of the Korean institute of surface engineering
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    • v.34 no.4
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    • pp.337-341
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    • 2001
  • TiN coating of high speed end mill is recently generalized. The study of coating layer using ion plating is mainly about the coating method and the why of the longer life of coated tools. In CNC machning process, metal cutting isn't carry out until the tools including the end-mill and so on are fractured. Namely, it is difficult precision processing when the cutting force of the cutting tool is near the limit the fracture cutting force. So, the estimate of the life by wear and fracture is important. Therefore, this study is about the method to estimate the capacity of the coating layer in relation to the tendency of cutting force and the influence of the cutting capacity of coated end-mill by the condition N2, Ar, temperature. The cutting length is in inverse proportion to the cutting force ratio. So, the life of the TiN coated end mill can be predicated by the ratio of the increase of the cutting force.

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Estimation and Projection of Work-life Expectancy by Increment/Decrement Work-Life Table Method (증감 노동생명표에 의한 노동기대여명의 측정과 전망)

  • Park, Kyung-Ae;Choi, Ki-Hong
    • Korea journal of population studies
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    • v.29 no.3
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    • pp.51-72
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    • 2006
  • In Korea, most studies have used the conventional Wolfbein and Wool method, which cannot be applied to women's work-life table because of bimodality and/or M curve of female labor force participation. The increment/decrement work-life table method, however, is equally applicable to both men and women, but requires individual data on employment transition. This paper demonstrates that the Garfinkle-Pollard method is the same as the increment/decrement work-life table method developed by Hoem, Schoen and Woodrow and adopted by BLS. The merit of Garfinkle-Pollard method is to produce work-life table using labor force participation rate without individual employment transition. This paper applies the Garfinkle-Pollard methods to the estimation and projection of work-life of Korean labor force for the period of 2000-2050, using the abridged life tables provided by Korean National Statistical Office and a projection of labor force participation rates. The work-life expectancy at 65 is 5.8 years for men and 4.1 years for women in 2000, and it increased to 7.7 years for men and 5.1 years in 2050. However, differences in work-life expectancy are found depending on the data processing of elderly labor force participation and mortality assumption. Detailed data on elderly labor force participation and further study on future mortality are required to estimate and project more accurate work-life expectancy.

Cutting Performance of TiAlN coated WC Insert Tip (TiAlN을 코팅한 WC공구의 절삭성능에 관한 연구)

  • 김형자;최현철;이규용
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 2001.06a
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    • pp.281-286
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    • 2001
  • TiAIN was deposited onto ISO P2O Cutting Insert Tip substrate by FVAS at the substrate temperature of 80$^{\circ}C$. Cutting and wear test have been performed with TiAIN coated and uncoated WC cutting tools, respectively. Uncoated WC cutting tool has been tested under similar cutting condition for comparison. Cutting force and tool wear of coated and uncoated carbide cutting tools were investigated by cutting length. In cutting test, cutting force of the coated insert tip was larger than the uncoated insert tip by tool wear. Configuration and wear of the coated tool were more stable and resistant than the uncoated. In tool life by the tool wear, the coated cutting tool life was rather longer than the uncoated when tested at high speed (V=250 m/min) than low speed (V=200 m/min), Cutting force, tool wear and life were analysised by tool dynamometer amp(3ch) and oscilloscope.

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Mechanical Characterization of the Pedicle Screw System for Thoracolumbar Spine (흉요추용 척추경 나사못시스템의 기계적 특성)

  • 이효재;최화순;안면환;송정일
    • Journal of Biomedical Engineering Research
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    • v.23 no.1
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    • pp.17-26
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    • 2002
  • The purpose of this study was to investigate the important Parameters of the Pedicle screw by estimating the mechanical characteristics of screws under static and dynamic loads. Methodology for estimating Parameters under static load was proposed. It was also shown that the fatigue life of the one-level system could be increased by changing the shape of screws. Load parameters of the single pedicle screw were friction force. bending moment. and holding force. The test results of the one-level system could be inferred from teat results of the sin91e screw under bending force Fatigue life of the one-level system with flexible rod was longer than that of the upper Part test without rod . Considering the drop of flexibility of the rod due to muscles and ligament, fatigue life of the one-level system could be estimated b? that of the single screw.