• 제목/요약/키워드: Cycle property

검색결과 365건 처리시간 0.039초

대도시 가족의 주거생활양식에 관한 연구 II -관련변수들의 특성을 중심으로- (A Study on the Housing Life Style of Families Living in Metropolitan Areas II -with special reference to characteristics of independent variable-)

  • 이연복;홍형옥
    • 대한가정학회지
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    • 제38권3호
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    • pp.43-57
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    • 2000
  • The aims of this study were to analyze the influence of related variables on a mode of housing life style, and the related variables to propensity to housing life stymie. The results of this study were as follows: 1. Variables influencing value orientation of family life were property and the price of housing. 2. Variables influencing spending habits were objective social class (SES), types of residence, education of wife, and price of housing. 3. Variables influencing propensity to using space were found to be objective social class (SES), education of wife, types of homeownership, and price of housing. 4. Variables influencing housing life style were objective social class (SES), subjective social class, housing class, family life cycle, housing life cycle, types of residence, site of residence, age of husband, age of wife, education of husband, education of wife, income, property, job of husband, types of homeownership, size of housing, and price of housing.

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동결/해동 열사이클이 PEFC의 GDL/MEA에 미치는 영향 (Freeze/Thaw cycle effects on GDLs and MEAs of PEFC)

  • 임남윤;박구곤;박진수;윤영기;이원용;임태원;김창수
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2006년도 춘계학술대회
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    • pp.96-98
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    • 2006
  • Proper water management is vital to achieve high performance and durability of PEFC (Polymer Electrolyte Fuel Cell). The effects of the residual water from PEFC after purge in shut-down processes on GDL/MEAs were investigated with freeze/thaw cycles Freeze/thaw cycle tests were conducted with single cells which were designed from transparent acryl plates. Single cells which contain several amount of residual water were cycles from $80^{\circ}C$ to $-28^{\circ}C$. The resistance changes of the single cells which have various amount of residual water were evaluated by ac-impedance analysis with 24 times of freeze/thaw cycles. Also, after the freeze/thaw cycles, the property changes were characterized by visual methods such as SEM, EPMA. Though it was difficult to observe noticeable property changes in the visual characterizations, the resistance of cells dramatically increased with the amount of remained water.

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자동차휠용 A356 알루미늄 합금의 주조조직이 피로특성에 미치는 영향 (Effect of Cast Microstructure on Fatigue Behaviors of A356 Aluminum Alloy for Automotive Wheel)

  • 송전영;박중철;안용식
    • 한국주조공학회지
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    • 제30권1호
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    • pp.46-51
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    • 2010
  • Recently, automotive industry is attempting to replace steels for automotive parts with light-weight alloys such as aluminum alloy, because of the growing environmental regulations governing exhaust gas and the engine effectiveness of a vehicle. The low cycle fatigue (LCF) and high cycle fatigue (HCF) properties as well as the microstructure and tensile property were investigated on the low pressure cast A356 aluminum alloy wheel, which was followed by T6 heat treatment. The cast microstructure of the alloy influenced significantly on the low cycle and high cycle fatigue behaviors. The rim part of cast aluminum alloy wheel showed higher low cycle and high cycle fatigue strength compared with the spoke part, which should be caused by higher cooling rate of rim part. The spoke part of the wheel showed coarser dendrite arm spacing (DAS) and wide eutectic zone in the microstructure, which resulted in the partial brittle fracture and lower fatigue life time.

Construction Cost Segregation Process using Building Information Modeling

  • Zhou, Rong;Li, Huimin;Zhang, Chengyi;Lv, Lelin;Tian, Junrui;Cakir, Sevilay Demirkesen
    • 국제학술발표논문집
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    • The 9th International Conference on Construction Engineering and Project Management
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    • pp.1106-1113
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    • 2022
  • Cost segregation helps reduce tax liabilities by reclassifying real property to personal property and accelerates tax depreciation of a property. A typical cost segregation study requires much time and high costs. This study proposed a BIM integrated cost segregation process that can be applied to any commercial building project. The proposed BIM-based cost segregation process was verified in a new commercial construction project. It approved that this approach can: (1) increase the cash flow for the owner and provide assistance to tax-paying enterprises; (2) enable the contractor to use it as an added value in the bidding process; (3) realize data sharing in a common platform to improve the cost segregation study efficiency and reduce costs and errors; (4) contribute to the asset management in the life cycle of buildings while filling in the blank of cost segregation process. Future studies will focus on the automation of cost segregation and asset management in building construction's life cycle.

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An Embedding of Multiple Edge-Disjoint Hamiltonian Cycles on Enhanced Pyramid Graphs

  • Chang, Jung-Hwan
    • Journal of Information Processing Systems
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    • 제7권1호
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    • pp.75-84
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    • 2011
  • The enhanced pyramid graph was recently proposed as an interconnection network model in parallel processing for maximizing regularity in pyramid networks. We prove that there are two edge-disjoint Hamiltonian cycles in the enhanced pyramid networks. This investigation demonstrates its superior property in edge fault tolerance. This result is optimal in the sense that the minimum degree of the graph is only four.

터빈 블레이드의 구조동역학해석에 근거한 시스템 인자들의 고 사이클 피로수명에 대한 영향도분석 (Study on the Effects of System Parameters on the High Cycle Fatigue Life Based on Structural Dynamic.analysis of a Turbine Blade System)

  • 권성훈;임홍석;유홍희
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2006년도 추계학술대회논문집
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    • pp.89-94
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    • 2006
  • In this paper, the effects of the system parameters on the high cycle fatigue life based on structural dynamic analysis of a turbine blade are investigated. Conventional studies have forcused on the fatigue life of turbine blades with specific system parameters. However, each parameter has statistical deviation because of inhomogeneity of material property, tolerance, and operating conditions. Therefore a methodology that estimates the effects of system parameter on the fatigue lift deviation is demonstrated.

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윤활환경에 따라 발생하는 소성변형량과 저주기 피로물성을 이용한 스커핑 수명 예측 (The Prediction of Scuffing Life due to Plastic Deformation and Low-cycle Fatigue Properties Under Various Lubricated Conditions)

  • 김병주;이영제
    • Tribology and Lubricants
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    • 제14권4호
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    • pp.7-14
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    • 1998
  • A correlation between the low-cycle fatigue life and the scuffing-failure life is demonstrated using the plastic strain increment in boundary lubricated sliding. Loadings proportional to hardness with three different lubricated conditions were used to evaluate the plastic strain increments. As the results of scuffing tests using vacuum pump oils in nitrogen gas, plastic strain increment shows 0.0062, and in the mineral oils and commercial engine oils in air, plastic strain increments show 0.0042 and 0.00092. Those are very useful to describe quantitatively the real lubricated sliding conditions, and are very effective to find the relation between the low-cycle fatigue life and the scuffing-failure life.

신뢰성 척도 및 분포의 적용 (Implementation of Reliability Measure and Distribution)

  • 최성운
    • 대한안전경영과학회지
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    • 제7권5호
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    • pp.175-184
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    • 2005
  • This paper presents the practial guide to implementation of reliability distributions. The applicability and property of various reliability distribution will then be illustrated. Main objective of this study is to present how to use reliability distributions summary with respect to the total life cycle management. This paper provides insight info the good aspects of using relability distributions properly.

퍼지AHP를 이용한 교통신호제어기의 교통대안확정방법 (A Method of Conclusion of Traffic Control Signal Proposal using Fuzzy Analytic Hierachy Process)

  • 진현수
    • 한국산학기술학회논문지
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    • 제9권6호
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    • pp.1592-1598
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    • 2008
  • 기존의 교통신호기의 방법은 고정신호제어기이다. 즉, 교통대안을 한 가지씩 채택하여 24시간 내내 이미 결정한 교통신호대안에 의존하여 주기 싸이클을 결정하는 방법이다. 교통신호 운영자가 교통대안을 잘못 입력하여 설정하게 되면 교차로내에서 잘못된 교통대안으로 인해 교통지체가 빈번하게 일어남을 알 수 있다. 교통대안은 눈으로 보아 설정하는 것이 아니고 유력한 교통대안을 서로 비교하여 가장 영향력 있는 교통대안을 설정하는 것이 교통신호제어에 유효하다. 본 논문에서는 고정신호제어기를 사용하여 제어기에 맞는 교통대안을 찾는 방법을 퍼지계층분석방법을 이용하여 찾는 방법을 모색하고 기존제어기와 비교 검토한다.

Procedural steps for reliability evaluation of ultrasonically welded REBCO coated conductor lap-joints under low cycle fatigue test condition

  • Michael De Leon;Mark Angelo Diaz;Hyung-Seop Shin
    • 한국초전도ㆍ저온공학회논문지
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    • 제25권4호
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    • pp.28-31
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    • 2023
  • This study presents a comprehensive procedure for the low cycle fatigue test of ultrasonically welded (UW) coated conductor (CC) lap-joints. The entire process is examined in detail, from the robust fabrication of the UW REBCO CC joints to the reliability testing under a low number of repeated cycle fatigue conditions. A continuous Ic measurement system enables real-time monitoring of Ic variations throughout the fatigue tests. The study aims to provide a step-by-step procedure that involves joint fabrication, electromechanical property (EMP) tests under uniaxial tension for stress level determination, and subsequent low-cycle fatigue tests. The joints are fabricated using a hybrid method that combines UW with adding In-Sn soldering, achieving a flux-free hybrid welding approach (UW-HW flux-free). The selected conditions for the low cycle fatigue tests include a stress ratio of R=0.1 and a frequency of 0.02 Hz. The results reveal some insights into the fatigue behavior, irreversible changes, and cumulative damage in the CC joints.