• 제목/요약/키워드: aging (deterioration)

검색결과 266건 처리시간 0.025초

모듈 단위 열화조건을 고려한 자동차용 칵핏 모듈 이음(BSR Noise)에 대한 시험적 고찰 (Experimental Study of being vehicle cockpit module BSR Noise considering the deterioration condition of the module unit)

  • 이철현;양정민;조진호;이원구;우창수
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2014년도 추계학술대회 논문집
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    • pp.791-795
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    • 2014
  • In this paper, in order to impart the aging condition of the parts, by configuring the cycle of temperature from low temperature was performed by applying the aging conditions for vehicle cockpit module. The reason for the selected modules of the cockpit vehicle parts, because the joint occurrence typical components of the room component is a first module and ceiling cockpit module. After setting the excitation profile using the BSR exciter only that this is for the module degradation after the initial and grasp the change in the dynamic characteristics of the modules based on the before and after deterioration may be made in the module, grasp the noise generating position I measured the noise and proximity. Was also visualized on the position of the joint is generated using a sound camera to objective results occurring where the joint is selected through subjective evaluation.

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실리케이트계열의 표면침투보강재를 이용한 열화방지기술개발 (Development of the Preventing Aging Technology Using Silicate Type Penetration Reinforcing Agent)

  • 김도겸;조명석;송영철;류금성
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
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    • pp.313-316
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    • 2006
  • The most serious cause of deterioration in the concrete structures is reinforcing corrosion due to the chloride attack and carbonation. Therefore, it is needed to protect durability and performance according to the appropriate materials and methods in the concrete structures. In general, several types of polymer and silicate are used as protecting deterioration agents of concrete structures, but these agents have many problems because of low durability and properties. The object of this study is to develop a preventing aging technology. The work involves the development of silicate type penetration reinforcing agent.

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건축 구조물 외단열 시스템의 열화 및 누수현상이 구조물 노후화에 미치는 영향 분석에 관한 연구 - 초고층 oo 아파트 외벽 누수 사례를 통하여 - (Analysis the influence of the exterior insulation deterioration and water leakage on the aging of concrete structure)

  • 박연진;박진상;선윤숙;오상근
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2007년도 춘계학술논문 발표대회
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    • pp.159-163
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    • 2007
  • We studied the example of various side on effect the aging of exterior materials for concrete structure by analyzing the reason of water leakage in exist serviced skyscraper apartment. For this side, we would like to suggest the proper waterproofing materials and construction methods resulted in the mechanical performance test. So, it could be ensured the leakage safety for using residence facility and crowd utilization after repairing. It may maximize the durability for the concrete structure.

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열화를 고려한 원자력발전소 철근콘크리트 보의 지진 취약도 해석 (Seismic Fragility Analysis of Deteriorated Reinforced Concrete Beams in Nuclear Power Plants)

  • 이명규;김문수;정연석;김인수;고성기
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2005년도 봄학술 발표회 논문집(I)
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    • pp.235-238
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    • 2005
  • The seismic fragility analyses of reinforced concrete propelled beam are performed to evaluate safety margin. The models were simulated by Latin Hyper-Cube (LHC) method considering various aging-related deterioration of RC beam. Fragility curves under various condition subjected to static load are compared. It is found that the 20$\%$ loss of top and bottom steel 15$\%$ lower than the undegraded beam in the ultimate strength. Seismic fragility analyses were performed to find out the effect of aging-related deterioration on the dynamic behaviour of RC beam.

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열적 열화 온도 변화에 따른 PAI 에나멜 각형코일의 절연 파괴 주파수 특성 (Insulation Breakdown Frequency Properties of PAI Enamelled Rectangular Coils According to Thermal Deterioration Temperature Variation)

  • 박재준
    • 한국전기전자재료학회논문지
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    • 제29권12호
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    • pp.829-834
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    • 2016
  • Coil specimens were prepared by continuous coating on a copper wire with flexible PAI (polyamideimide) and PAI/nanosilica (5 wt%) varnish and thermally aged at 150, 200 and $250^{\circ}C$ for 5, 10 and 15 days, respectively. AC insulation breakdown voltage was investigated under inverter surge condition at 60 Hz and 1,000 Hz and insulation breakdown voltage decreased with increasing aging temperature and aging time at each 60 and 1,000 Hz.

Relationship of Seed Germination and Lipoxygenase Activity in Soybean

  • Lee, Suk-Ha;Son, Beom-Young;Lee, Yeong-Ho;Lee, Hong-Suk
    • 한국작물학회지
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    • 제47권2호
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    • pp.123-126
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    • 2002
  • Lipoxygenase might be associated with seed deterioration by catalyzing the incorporation of molecular oxygen into fatty acids and generating free radicals. This study was performed to determine whether seed lipoxygenase activity would alter soybean seed longevity. In this study, germination percentage of lipoxygenase-lacking cultivar Jinpumkong2 (lx1lx1lx2lx2lx3lx3) was lower than that of Taekwangkong (Lx1Lx1Lx2Lx2Lx3Lx3). Segregation ratio for the three lipoxygenase isozymes of the F2-derived from the cross between Taekwangkong and Jinpumkong2 was fitted to 9 (Lx1Lx2Lx3) : 3 (Lx1Lx2lx3) : 3 (lxllx2Lx3) : 1 (lx1lx2lx3), suggesting the tight linkage between the Lx1 and Lx2 loci. Germination percentages varied widely but not differed among lipoxygenase isozyme types of F$_3$ seeds before and after accelerated aging. Seed coat of Jinpumkong2 was damaged severely following accelerated aging, whereas that of Taekwangkong was not. Thus, seed of lipoxygenase-lacking soybean cultivar, Jinpumkong2 showed greater deterioration compared with that of the normal Taekwangkong. However, the presence or absence of lipoxygenase activity had no effect on soybean germination.

노화 시계를 이용한 알츠하이머병 환자의 후성유전학적 연령 예측 (Epigenetic Age Prediction of Alzheimer's Disease Patients Using the Aging Clock)

  • 김진영;조광원
    • 통합자연과학논문집
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    • 제16권2호
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    • pp.61-67
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    • 2023
  • Human body ages differently due to environmental, genetic and pathological factors. DNA methylation patterns also differs depending on various factors such as aging and several other diseases. The aging clock model, which uses these differences to predict age, analyzes DNA methylation patterns, recognizes age-specific patterns, predicts age, and grasps the speed and degree of aging. Aging occurs in everyone and causes various problems such as deterioration of physical ability and complications. Alzheimer's disease is a disease associated with aging and the most common brain degenerative disease. This disease causes various cognitive functions disabilities such as dementia and impaired judgment to motor functions, making daily life impossible. It has been reported that the incidence and progression of this disease increase with aging, and that increased phosphorylation of Aβ and tau proteins, which are overexpressed in this disease and accelerates epigenetic aging. It has also been reported that DNA methylation is significantly increased in the hippocampus and entorhinal cortex of Alzheimer's disease patients. Therefore, we calculated the biological age using the Epi clock, a pan-tissue aging clock model, and confirmed that the epigenetic age of patients suffering from Alzheimer's disease is lower than their actual age. Also, it was confirmed to slow down aging.

효소에 의한 제탁조작과 맥주의 발포성 제I보. 제조공정중의 발포성상실 (Enzymatic Chillproofing and Beer Foam Stability- Part 1. Foam Deterioration during Manufacturing Processes)

  • Pack, M.Y.
    • 한국미생물·생명공학회지
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    • 제3권2호
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    • pp.83-87
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    • 1975
  • 발효직후의 처여맥관가 갖인 우수한 발포성이 제조공정이 끝날 무렵에는 현저히 손실되는 사실을 발견하고 그 원인을 조사한 결과 효소에 의한 제탁조작을 동반한 숙성 및 멸균과정이 맥주의 발포성을 크게 상실시킨다는 것이 증명되었다.

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Mitochondria: multifaceted regulators of aging

  • Son, Jyung Mean;Lee, Changhan
    • BMB Reports
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    • 제52권1호
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    • pp.13-23
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    • 2019
  • Aging is accompanied by a time-dependent progressive deterioration of multiple factors of the cellular system. The past several decades have witnessed major leaps in our understanding of the biological mechanisms of aging using dietary, genetic, pharmacological, and physical interventions. Metabolic processes, including nutrient sensing pathways and mitochondrial function, have emerged as prominent regulators of aging. Mitochondria have been considered to play a key role largely due to their production of reactive oxygen species (ROS), resulting in DNA damage that accumulates over time and ultimately causes cellular failure. This theory, known as the mitochondrial free radical theory of aging (MFRTA), was favored by the aging field, but increasing inconsistent evidence has led to criticism and rejection of this idea. However, MFRTA should not be hastily rejected in its entirety because we now understand that ROS is not simply an undesired toxic metabolic byproduct, but also an important signaling molecule that is vital to cellular fitness. Notably, mitochondrial function, a term traditionally referred to bioenergetics and apoptosis, has since expanded considerably. It encompasses numerous other key biological processes, including the following: (i) complex metabolic processes, (ii) intracellular and endocrine signaling/communication, and (iii) immunity/inflammation. Here, we will discuss shortcomings of previous concepts regarding mitochondria in aging and their emerging roles based on recent advances. We will also discuss how the mitochondrial genome integrates with major theories on the evolution of aging.

노화에 따른 작업기억능력의 저하에 영향을 받는 영상 속 자막인식위치 연구 (A Study on the Influence Exerted on Subtitle Locations in Videos by the Deterioration of Working Memory Ability due to Aging)

  • 김상엽;정재범;박장호;남기춘
    • 감성과학
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    • 제22권4호
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    • pp.31-44
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    • 2019
  • 본 연구의 목적은 노화에 따른 작업기억능력의 저하에 영향을 받는 자막인식위치에 대해 탐구하는 것이다. 이를 위해, 본 연구에는 주니어 집단(평균 나이: 26세, 표준편차: 3.06, N=27)과 시니어 집단(평균 나이: 61.69세, 표준편차: 4.18, N=26)이 참여했으며, 실험 과제로는 실험 참가자들의 작업기억능력을 측정하기 위한 N-back 과제와 자막인식위치를 측정하기 위한 동영상자막확인 과제가 사용되었다. N-back 과제 수행 결과, 시니어 집단이 주니어 집단보다 과제에 대한 반응속도가 느리고 정답률이 낮게 나타나, 시니어 집단은 주니어 집단에 비해 작업기억능력의 저하가 나타났다는 것을 의미했다. 또한, 동영상자막확인 과제 수행 결과, 노화에 따른 작업기억능력의 저하에 부정적인 영향을 받는 자막위치는 화면의 '좌측-아래'이고 긍정적인 영향을 받는 자막위치는 화면의 '좌측-가운데'으로 나타났다. 나머지 화면 위치에서는 노화에 따른 작업기억능력의 저하에 영향을 받지 않았다. 결과적으로 본 연구 결과를 통해서 연령의 증가에 따른 작업기억능력의 저하에 부정적 혹은 긍정적 영향을 받는 영상 속 자막인식위치에 대해서 살펴볼 수 있었으며, 이는 영상에 자막을 제시해야할 경우 시청자의 연령을 고려하여 자막위치를 선정하면 효율적으로 시청자에게 정보를 제공할 수 있다는 것을 의미했다.