• Title/Summary/Keyword: Safe life design

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A Study on the Design against Metal Fatigue (파로설계에 관한 소고)

  • Lee, Sun-Bok
    • 한국기계연구소 소보
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    • v.4 no.1
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    • pp.19-26
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    • 1981
  • Fatigue, the birth and growth of cracks in metal parts subjected to repeated loading, has been a problem plaguing engineers since the Industrial Revolution and the advent of rotating or reciprocating machinery. Designing against metal fatigue was studied briefly in several aspects. Examples of fatigue failures were shown. Fatigue was classified by loading: uniaxial Fatigue, multiaxial fatigue, cumulative fatigue da¬mage. Fatigue design criteria were discussed: Infinite-Life Design, Safe-Life Design, Fail-Safe Design, and Damage Tolerant Design. Mitigation of notch effects by design, improvement of fatigue strength of metal parts by residual stress and surface finishing were discussed. Relative fatigue beha¬vior was studied under various environmantal conditions. Especially the effects of corrosion, temperature, fretting, and irradiation were covered.

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A study on the Safe-Life Village Design for the Citizen Security (시민보호를 위한 생활안전 마을지도 설계에 관한 연구)

  • Lee, Tae Shik;Seok, Geum Cheol;Cho, Won Cheol
    • Journal of Korean Society of Disaster and Security
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    • v.6 no.3
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    • pp.43-48
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    • 2013
  • This paper focused on the continuing the citizen safety, the contributing the local economy's activation, and the improving the safe and the social walfare on the civil environment. Seoul metropolitan nominated the model village the Buggaja 2 dong of the Seodaemoon-gu for the making safe village in the 2013. It is designed the village map for the safe life, discovered the dangerous factor about the various and social facilities which is a road, a walking way, a school, a enjoy place for the children, a Thema place, the leasure place, facilities etc., and improved the model village for the incident's and accident's reduction education and training from 2011 to 2013. The results on the discovering and improving activities by the resilient safe monitoring activity, in the 2011 the village is reduced the 23 people from the 151 people to the 128 people in the dead number into the total citizen 34,000 during a year, is showed the excellent values, which the dead people reduced the 23 people in the village, which the safe-life result was over the 12.8% in the national average. For the making resilient city, for the supporting the visitors which it looks around the safe-life model village, the tracking road map is designed, and the tenth safe life factors is showed.

Development of extended safe petri net model for discrete system control and scanning algorithm for real time control (비연속 시스템 제어를 위한 확장된 safe petri net 모델과 실시간제어를 위한 scanning algorithm의 개발)

  • 황창선;서정일;이재만
    • 제어로봇시스템학회:학술대회논문집
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    • 1988.10a
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    • pp.338-342
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    • 1988
  • Recently, in sequence control systems, high flexibility and maintenance of control software are required. This is because product life cycles become shorter and control specification must be changed frequently. The authors extend the concept of Safe Petri Net to develop the design and analysis tool for sequence control systems taking the safeness and notation of input/output functions into consideration. Extended Safe Petri Net (S-Net) is proposed as such a new graph model and real time scanning algorithm based on S-Net is developed.

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Life Evaluation of Gas Turbine Engine Disk based on Retirement for Cause Concept (Retirement For Cause 개념에 의한 가스터빈 디스크 수명의 평가)

  • Nam, Seung-Hun;Park, Jong-Hwa;Kim, Jong-Yeop
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.26 no.2
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    • pp.365-373
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    • 2002
  • For gas turbine engines, the safe life methodology has historically been used fur fatigue life management of failure critical engine components. The safe retirement limit is necessarily determined by a conservative life evaluation procedure, thereby many components which have a long residual life are discarded. The objective of this study is to introduce the damage tolerant design concept into the life management for aircraft engine component instead of conservative fatigue life methodology which has been used for both design and maintenance. Crack growth data were collected on a nickel base superalloy which have been subjected to combined static and cyclic loading at elevated temperatures. Stress analysis fur turbine disk was carried out. The program for computing creep-fatigue crack growth was developed. The residual lifes of turbine disk component under various temperatures and conditions using creep-fatigue crack growth data were estimated. As the result of analysis, it was confirmed that retirement fur cause concept was applicable to the evaluation of residual life of retired turbine disk which had been designed based on the conventional fatigue life methodology.

A Study on Expressing the Methods of Light for Creating Safe Space (안전한 공간 조성을 위한 빛의 표현방안 연구)

  • Kim, Myoung-Seon;Moon, Jeong-Min
    • Journal of the Korean housing association
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    • v.27 no.3
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    • pp.39-46
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    • 2016
  • On account of the increasing crime rates annually and the consequent rising anxiety, safety has become an important topic in the aspect of environmental formation to provide decent lives to urban dwellers. As a result, great emphasis has been placed in the importance of Crime Prevention through Environmental Design (CPTED), a design method which utilizes physical environmental design to prevent crime. The definition of CPTED encompasses the technological level of crime prevention as well as comprehensive environmental design which takes into consideration fear or terror in view of human recognition and emotion. However, the current application method of CPTED in Korea is still limited to the technical supplementation of facilities, such as CCTV and streetlight, and fragmental modification like village mural paintings. Moreover, the guideline for CPTED in Korea is only a theoretical adaptation of foreign books and does not offer sufficient studies for a practical design method that will improve the life of city dwellers. The purpose of this study is to examine design methods for safe environment construction in accordance with the changing concept of CPTED by understanding the characteristic of space and analyzing the how the methods of light are expressed. This study aims to provide basic material which will serve as a guideline in creating a safe environment in the future.

A Study on the Fatigue Strength of the Welds of Membrane Type LNG Tank (멤브레인 방식 LNG탱크 용접부의 피로강도에 관한 연구)

  • 김종호
    • Journal of Advanced Marine Engineering and Technology
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    • v.21 no.5
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    • pp.542-548
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    • 1997
  • In this study an evaluation method of fatigue strength of membrane type LNG tank is presented with FEM analysis and experimental approach of seam and raised edge welds. The study contains the following : l)FEM analysis of test specimens 2)Fatigue tests of seam and raised edge welds 3)Estimation of cumulative damage factor of the welds on the basis of safe life design concept complying with the rules of classification society 4)Review of the effect of mean stress on the fatigue strength 5)Modelling of fatigue life of the welds which is changeable by weld heights With the results obtained in this study, a model ${\Delta}{\delta}/h^2=0.13553\;{N_{f}}^{-0.3151}$ for seam and raised edge welds having a given weld height is proposed to be useful for designers and inspectors.

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Study on aircraft fatigue life substantiation method (항공기 피로수명 입증방법 연구)

  • Kim, Sung Joon;Kim, Tae-Uk
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.24 no.1
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    • pp.41-46
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    • 2016
  • This paper reviews and summarizes overall fatigue substantiation method of aircraft. The fatigue substantiation method has been studied using the related regulation and examples of industry application. And the comparisons of fatigue substantiation procedure between safe-life and damage tolerance design have been performed. Fatigue substantiation methods have wide variability depend on design methodology and type of aircraft such as fixed wing and rotorcraft. In this study, fatigue substantiation methodologies have been reviewed using analysis and test methods.

A study on the Means of Egress Codes for Interior Architecture in the United States - Focused on Evacuation Elements in the Interior Architectural Design - (미국의 실내건축 피난 규정에 관한 연구 - 실내건축계획에 있어 피난 요소를 중심으로 -)

  • Kim, Young-Sung;Cho, Sung-O
    • Korean Institute of Interior Design Journal
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    • v.27 no.3
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    • pp.24-32
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    • 2018
  • The law reflects the situation of the times, understands the society, and shows the will of the state and the community. The Means of Egress should be maintained from design to construction, supervision, as well as use, in order to protect the lives and property of the residents as well as the safe use of the facilities. However, Interior Architects are think that evacuation and safety regulations are complex elements that change frequently and may inhibit the idea of design. The purpose of this study is to propose a design method for the use of safe facilities in the interior architectural design on the evacuation regulations affecting the actual design by the IBC(the International Building Code) and NFPA(National Fire Protection Association) LSC (Life Safety Code). The research method is to investigate and analyze the provisions related to the evacuation of interior architecture in the US and to understand the current regulations and the evacuation regulations. We suggest to design method to the details of the hallway, corridors, aisle accessway, door way, exit path, In particular, the design of furniture, tables and chairs layout that could be obstacles to evacuation situations is presented.

A Study on Estimation of Infinite Fatigue Life in Cruciform Fillet Welded Joint (십자형 필릿 용접부에서의 무한 피로수명 평가에 관한 연구)

  • Lee, Yong-Bok
    • Journal of the Korean Institute of Gas
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    • v.17 no.1
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    • pp.19-25
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    • 2013
  • The joining methods of steel structures of gas facilities, bridges, ships etc. by welding are composed mostly of T-type or cruciform fillet welding and full penetration or partial penetration according to the uses and the shape of the structures. In this study, it was examined the characteristics of fatigue crack according to penetration depth in relation to material thickness in the cruciform fillet welded joints. From the results, it was investigated the safe design stresses within the range of infinite life. When the LOP length is long the range of infinite life is small with root failure and when the LOP length is short the range of infinite life is large with teo failure. For the specimen of material thickness, 20mm welded by 3 pass compared with 10mm, 15mm welded by 2 pass, the fatigue strength and the range of infinite life was more improved by increasing of notch toughness from formation of micro-ferrite acicular structure.

Extraction of Pattern Language for Communal Housing of Families with Children - Using Contents Analysis Method - (육아가구 공동체주택 계획을 위한 패턴언어 추출 연구 - 아동과 육아가구 환경 관련 문헌의 분석을 통해 -)

  • Lim, Yea-Ji;Lee, Yeun-Sook
    • Journal of the Architectural Institute of Korea Planning & Design
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    • v.35 no.9
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    • pp.77-88
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    • 2019
  • This study started with the aim of creating a parenting environment for raising children as a solution to the problem of low fertility. Communal housing is a type of housing where professional childcare environment and lives of family with children can be achieved in community space. It is an environment that supports the development of the child and life of family. However, there is no guidance system for planning such an environment. Therefore, this study aims to develop a pattern language for communal housing of families with children. The research method comes in two steps. First, the documents that provided pattern language and design guidelines about the environment of child and families with children were analyzed. Second, experts specialized in child education, women and family, environmental design were interviewed. As a result of analysis of characteristics of derived pattern language, convenience, safe feeling, comfortability in residential unit, movement, safe feeling, convenience in intermediate space convenience, safe feeling, control in community space were high. The pattern language of this study grafted the items that have proven to be important over a long period of time and the environmental design concepts for families with children in the community space. So it enabled differentiation from existing pattern language or design guidelines.