• 제목/요약/키워드: Long Life Test

검색결과 611건 처리시간 0.269초

고강성 기층재를 적용한 장수명 아스팔트포장 공법 개발 (Development of Long-Life Asphalt Pavements Method Using High Modulus Asphalt Mixes)

  • 이정훈;이현종
    • 한국도로학회논문집
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    • 제8권3호
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    • pp.49-61
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    • 2006
  • 본 연구에서는 포장의 설계수명과 공용년수를 증대시켜 아스팔트 포장의 유지보수비용을 감소시킬 수 있는 장수명 아스팔트 포장 공법을 제안하였다. 이를 위한 고강성 바인더를 개발하여 다양한 실내 물성시험을 수행하였으며 고강성 기층재의 평가를 위해 실내 공용성시험 및 포장가속시험을 실시하여 기존의 일반아스팔트 혼합물과 비교 평가하였다. 그 결과 고강성 기층재는 일반 아스팔트 혼합물에 비해 강성이 증가하였고 수분손상 피로균열 및 소성변형 저항성 등에서 우수한 것으로 평가되었다. 또한, 장수명 아스팔트 포장의 설계를 위해 구조해석을 실시하여 DB를 구축하였으며 이 자료를 이용해 다중회귀분석 프로그램인 SPSS로 포장체 거동모형을 개발하였다. 여기서 개발된 포장체 거동모형과 실내 외 시험결과를 기초로 장수명 아스팔트 포장 설계를 위한 소프트웨어를 개발하였으며 포장의 최적단면 및 구성을 설정하였다. 이렇게 설정된 장수명 포장의 아스팔트 층 단면 두께는 29cm로 이 단면의 경제성을 확인하기 위하여 생애주기 비용분석을 실시하였다. 그 결과 장수명포장이 기존 고속도로(경부)와 초기시공비용이 동일하면서 생애주기 비용측면에서 유리한 것으로 확인되었다.

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Effects of Awareness of Good Death and End-of-Life Care Attitudes on End-of-Life Care Performance in Long-Term Care Hospital Nurses

  • Kim, Sun-Hee;Kim, Eun-Young
    • Journal of Hospice and Palliative Care
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    • 제24권1호
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    • pp.26-35
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    • 2021
  • Purpose: The purpose of this study was to determine the effects of awareness of good death and end-of-life care attitudes on end-of-life care performance in long-term care hospital nurses. Methods: This study used a cross-sectional study design. The participants were 147 nurses working at six long-term care hospitals with more than 200 beds in B city, South Korea. Data were collected using self-reported questionnaires, and analyzed with descriptive statistics, the t-test, analysis of variance, Pearson correlation coefficients, and multiple stepwise regression analysis using IBM/SPSS 26.0 for Windows. Results: The participants' awareness of good death, end-of-life care attitudes, and end-of-life care performance were positively correlated. The factors affecting end-of-life care performance were age, education level, awareness of good death, and end-of-life care attitudes; these variables explained 19.0% of end-of-life care performance. Conclusion: In order to improve long term care hospital nurses' end-of-life care performance, continuing education and training should be provided regarding awareness of good death and end-of-life care attitudes.

스테인리스 스틸-나트륨 히트파이프의 장기 수명 시험 (Long-Term Life Test of A Stainless Steel-Sodium Heat Pipe)

  • 박수용;정의국;부준홍;강환국;유정현;박상훈
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 추계학술대회
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    • pp.1058-1062
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    • 2004
  • High-temperature cylindrical stainless steel/sodium heat pipe was manufactured and tested under long-term operation. The container material was stainless steel 316L and the working fluid was sodium. The heat pipe was 25.4 mm in diameter and 1000 mm in length with a two-layer screen mesh wick. The evaporator part was 600 mm and the condenser part was 300 mm in length. Total measurement points on heat pipe were 15 points and 12 points were located in condenser part. The heat pipe was heated for 142 days(3400 hours) at $800^{\circ}C$. In the test period, the maximum temperature difference was increased from $18^{\circ}C$ o $28^{\circ}C$ and the maximum thermal resistance was as low as $0.015^{\circ}CW$.

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장시간 사용된 가스터빈 블레이드의 저주기피로 손상도 평가 (Evaluation of Low Cycle Fatigue Damage of Gas Turbine Blades Used for a Long Time)

  • 허인강;김재훈
    • 한국안전학회지
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    • 제33권3호
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    • pp.8-14
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    • 2018
  • Ni-base superalloy has excellent resistance to extreme environments such as high temperatures and high stresses and are used as materials for large gas turbines. In this paper, the specimens were taken from the blade that were used for a long time, and their life span was studied by microstructure analysis and avoidance of cursing. The microstructural analysis of the specimens was carried out using a OM and SEM to observe the coarsening, carbides on gamma prime. Low-cycle fatigue tests were performed on new material and airfoil of long time-used blade. The test was conducted under various deformation conditions and temperature conditions of $760^{\circ}C$ and $870^{\circ}C$. The low cycle fatigue test was carried out using the Coffin-Manson equation and the fatigue life was predicted. After the test, crack path and fracture surface were analyzed using SEM.

버터플라이밸브 성능 및 수명시험장치 개발과 개선에 관한 연구 (A Study of Development and Improvement for Butterfly Valve Performance & Life Test Equipment)

  • 이기천;김형의;정동수;김재훈
    • 한국유체기계학회 논문집
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    • 제15권2호
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    • pp.51-56
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    • 2012
  • The butterfly valve has been used over all industries. It has been studied to improve its performance through the theoretical analysis and the test in industry. Though products adopted those improvements have been sold in markets, manufacturers often launch products without the life test. One reason is because of the long development period and financial difficulties. The other is the lack of the design and fabrication experiences on building the life test equipment. Thus, this study has been researched for the design and fabrication of our life test equipment, and developed and improved the equipment to check the leakage of the valve with the naked eyes during the test.

플라스틱 호스 조립체의 가속수명시험 방법에 대한 연구 (A Study on Procedures of the Accelerated Life Testing for Hose Assemblies)

  • 이용범;김형의;김종기;박종호
    • 연구논문집
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    • 통권34호
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    • pp.79-85
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    • 2004
  • There are several types of life test method for hose assemblies. The two major tests used for hose assemblies are impulse test and burst test. And magnification adjustment of impulse pressure, heating of testing oil and repetitive motions of bending and straightening of testing hose are also performed for accelerating the life. According to the manufacture process of hose and swaging process of fitting, there is a difference in the life of hose assemblies from minimum 7 times to maximum 40 times during the life test in the same functioning condition. Like this, the life test of hose which has a wide scope of life distribution gives a problem that observation should take a long time to find out the existence of the bursting from the beginning of the test to the completion of bursting of hose assemblies. Therefore, this research proposes a process of concentrating on the defective section of hose assemblies and maximizing the life acceleration by giving 'Knockdown stress' to hose assemblies just until before the hose assemblies get out of order.

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노인요양 시설 노인의 삶의 질과 시설 서비스, 가족 지지의 관계 (The Relationship between the Quality of Life, Care Services, and Family Support of Elderly Residents in Long-Term Care Facilities)

  • 신승호;신소홍
    • 문화기술의 융합
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    • 제7권2호
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    • pp.227-237
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    • 2021
  • 이 연구의 목적은 노인요양 시설 입소 노인의 삶의 질에 시설 서비스가 영향을 미치는지 파악하고, 가족 지지의 매개효과를 알아보는 것이다. 연구 대상은 대구·경북 지역의 노인요양 시설에 입소하여 생활하는 노인 192명이다. SPSS 22.0 program을 활용하여 기술통계, t-test와 ANOVA, Pearson의 상관관계 분석, 회귀분석을 실시하였다. 연구 결과 연령, 학력, 자녀의 경제 수준, 입소 계기, 입소 기간에 따라 삶의 질에 차이가 있었다. 삶의 질에 영향을 미치는 요인은 연령, 학력, 자녀의 경제 수준, 입소 계기, 입소 기간 그리고 시설 서비스로 나타났으며, 가족 지지는 시설 서비스와 삶의 질의 관계에서 매개 요인으로 밝혀졌다. 요양 시설 입소 노인들의 삶의 질 개선을 위한 간호 중재 계획 수립의 정보가 될 것이다.

장수명주택 벽배관 시스템의 양변기 하중저항성에 대한 실험적 연구 (An Experimental Study on the Load Resistance of Toilet Bowl in Long-Life Housing Infill System)

  • 이종호;서동구;김은영;황은경
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2019년도 춘계 학술논문 발표대회
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    • pp.211-212
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    • 2019
  • It is possible to realize the concept of long-life housing by utilizing the wall piping infill system. However, when using the wall piping infill system, there is no detailed standard in Korea. Problems may occur in actual use. In this study, we use the results obtained from the performance test method as a basic data. Since the load resistance test of the toilet is not available in Korea, GB 6952 (Sanitary wares) of China is applied. According to the experiment of load resistance of the toilet in this study, the strain recovery ability was good. However, it is not possible to exclude the possibility of permanent deformation of the toilet seat due to long - term repeated loading. Therefore, it is necessary to consider the stiffness enhancement of the wall (steel frame) to the fixing part when installing the toilet in the wall pipe infill system.

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다단계 모의 열화재의 재료강도 평가와 수명예측 (Strength Evaluation and Life Prediction of the Multistage Degraded Materials)

  • 권재도;진영준;장순식
    • 대한기계학회논문집
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    • 제17권9호
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    • pp.2271-2279
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    • 1993
  • In the case of life prediction on the structures and machines after long service, it is natural to consider a degradation problems. Most of degradation data form practical structures are isolated data obtained at the time of periodical inspection or repair. From such data, it may be difficult to obtain the degradation curve available and necessary for life prediction. In this paper, for the purpose of obtaining a degradation curves, developed the simulate degradation method and fatigue test and Charpy impact test were conducted on the degraded, simulate degraded and recovered materials. Fatigue life prediction were conducted by using the relationship between fracture transition temperature (DBTT : vTrs) obtained from the Charpy impact test through the degradation process and fatigue crack growth constants of m and C obtained from the fatigue test.

천초근의 발암성 연구를 위한 분석 및 안정성 시험 (Stability Test and Analysis of Rubia cordifolia for Carcinogenicity Study)

  • 김대현;박진호;김승현;성상현
    • 생약학회지
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    • 제43권2호
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    • pp.147-151
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    • 2012
  • The marker constituent was isolated from Rubia cordifolia as a major compound. Quantitative method for the marker of the natural medicine was developed using HPLC-DAD and using established method the extract of Rubia cordifolia was evaluated. In addition, long term and accelerated stability test in the extract was examined for six months. No significant change in content of the marker constituent of the extract observed during the period of long term test.