• Title/Summary/Keyword: Design change

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A Study on the Design Change of High-Risk Temporary Structures (재해 위험도가 높은 가설구조물의 설계변경에 관한 연구)

  • Oh, T.K.;Kim, Y.G.;Lee, M.G.;Paik, S.W.;Woo, I.S.;Song, C.G.
    • Journal of the Korean Society of Safety
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    • v.29 no.1
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    • pp.37-40
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    • 2014
  • Article 29(3) of Occupational Safety And Health Act, which states a contractor can request a design change to an employer of businesses under the risk condition of construction of temporary structure, was established. Accordingly, in this study, recent fatal accidents caused by temporary structures were analyzed, and the level of inclusion of temporary structures in the design document were examined, and high risk temporary structures were classified. In addition, the requirements of design change of temporary structures were presented, and the qualifications of expert to certify the design change were proposed.

Case Study and Standard Process Analysis of Change Order in Design for Road Tunnel Project (터널공사 사례분석에 의한 설계변경 표준프로세스 구성방안)

  • Kang Leen-Seok;Kim Dong-Kwang;Jung Won-Myoung;Lee Seung-Ryul;Kim Hyun-Soo
    • Proceedings of the KSR Conference
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    • 2005.11a
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    • pp.1149-1152
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    • 2005
  • Recently, tunnel structure is being widely used in railway or roadway construction projects because earthwork causes large cutting and damages in environmental factors. However, there are many changes of design by different items comparing with design phase in tunnel structure by uncertain drawings. This study develops a standard process for the change of design to reduce change orders in construction phase.

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Design-Build Change Order Impacts in Highway Projects

  • Ryu, Kyeong Rok;Choi, Kunhee;Ryoo, Boong Yeol;Kang, Julian H.
    • International conference on construction engineering and project management
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    • 2015.10a
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    • pp.371-375
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    • 2015
  • Design-Build (DB) has gained in popularity in roadway projects due to its defining advantage to improve communication and fast-track project delivery. However, very little is known about the impact of change order frequency and occurrence timing pertaining to DB projects. The study analyzes their impacts on project time and cost performance by conducting a rigorous numerical analysis drawing on 530 3R (rehabilitation, reconstruction, and resurfacing) projects completed between 2002 and 2011 in Florida by using a multiple linear regression. The results indicate that DB outperformed Design-Bid-Build in project cost as well as time. Critically, the regression analysis signifies that earlier change order occurrence caused more unfavorable impacts on schedule and cost. The proposed analyses and models will lead to the improved ability of agencies to quickly and more reliably estimate the potential change order impacts on schedule and cost.

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A Hybrid Monitor (Rib, Boss) Design System with a Function Based Design and a Knowledge Based Design (기능기반설계와 지식기반 형상설계를 이용한 하이브리드 모니터 마스크(리브, 보스) 설계시스템)

  • Lee S.H.;Chun H.J.;Jeon S.M.
    • Korean Journal of Computational Design and Engineering
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    • v.11 no.2
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    • pp.77-87
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    • 2006
  • It is necessary to change the existing design process to cope with a short life-cycle product and various customer's demands. Also a frequent design change may delay the whole design process and it will increase the unit cost of the production. New alternatives or techniques have emerged to solve the existing design problems, such as a knowledge based engineering, an intelligent CAD, a function based design, and so on. In this paper, we propose a hybrid design system with a knowledge based design methodology and a function based design technique. The knowledge based design is good at a frequent design change and the function based design is effective to extract a core design behavior. In an early design process, the system utilizes a core design behavior through the function based design process. On the other hand, the system manages complicated design issues with the knowledge based design technique in the detailed design process. We conclude that the hybrid design system can bring fair effects on implementing an efficient design environment in aspect of time and expense.

Predicting the Design Rainfall for Target Years and Flood Safety Changes by City Type using Non-Stationary Frequency Analysis and Climate Change Scenario (기후변화시나리오와 비정상성 빈도분석을 이용한 도시유형별 목표연도 설계강우량 제시 및 치수안전도 변화 전망)

  • Jeung, Se-Jin;Kang, Dong-Ho;Kim, Byung-Sik
    • Journal of Environmental Science International
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    • v.29 no.9
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    • pp.871-883
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    • 2020
  • Due to recent heavy rain events, there are increasing demands for adapting infrastructure design, including drainage facilities in urban basins. Therefore, a clear definition of urban rainfall must be provided; however, currently, such a definition is unavailable. In this study, urban rainfall is defined as a rainfall event that has the potential to cause water-related disasters such as floods and landslides in urban areas. Moreover, based on design rainfall, these disasters are defined as those that causes excess design flooding due to certain rainfall events. These heavy rain scenarios require that the design of various urban rainfall facilities consider design rainfall in the target years of their life cycle, for disaster prevention. The average frequency of heavy rain in each region, inland and coastal areas, was analyzed through a frequency analysis of the highest annual rainfall in the past year. The potential change in future rainfall intensity changes the service level of the infrastructure related to hand-to-hand construction; therefore, the target year and design rainfall considering the climate change premium were presented. Finally, the change in dimensional safety according to the RCP8.5 climate change scenario was predicted.

Estimation of the vibration fatigue of a linear elastic system based on a desiign sensitivity analysis (설계 만감도 해석을 활용한 선형 시스템 진동내구 평가)

  • Kim, Chan-Jung;Kim, Ku-Sik;Kang, Ho-Young;Jin, Yeo-Hwa;Lee, Bong-Hyun
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2010.10a
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    • pp.491-496
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    • 2010
  • The direct design modification of problematic component is disallowed in order to sacrifice other major factors such as a stability or a major performance. So, the best design policy is to risvise the immature structural medchanism under the minimal design change as soon as possible. For this paper presents a new design sensitivity analysis based on transmissibility rtio (TR) of response acceleration to find a proper candidate for the minimal design modification. The new sensitivity analysis is based on the fact that the sensitivity of TR over a small design change is inversly proportinal to the magnitude of TR. The theory of proposed design sensitivity analysis is simulated with the variance of TR over a dynamic change. Then, new methodology is appplied for a linear elastic specimen to detect the most sensitive node over a design change using measured accleration data during uni-axial vibration test, The physical verification of the sensitivity method is conducted on the CAE model of a linear elastic specimen by adding concentration mass and the vibration fatigue of the simple specimen is analyzed to estimate the relationship between fatigue behaviors and sensitivity consequences.

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Aspect of Human-Centered Design in Contemporary Design of Time and Change : Focus on Analysis of Affordance and Psychological Bases (현대 시간성 디자인의 인간중심 디자인적 측면 : 어포던스에 의거한 행태지원 측면 분석을 중심으로)

  • Hong, Eui-Taek;Lee, Jeong-Min
    • The Journal of the Korea Contents Association
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    • v.7 no.4
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    • pp.91-102
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    • 2007
  • Post-modern period differentiates itself from Modern period in many aspects. One of these is the emphasis on phenomena which are ephemeral and changing. This paper looks at the psychological bases of these expressions of time & change in contemporary design and their affordances on human behavior. It also analyzes the types of time & change design on the basis of the behaviors they afford. This will lead us to the understanding of how the design including time & change expresses the spirit of the age and how it can play positive roles in human psychology.

Children's Bent Wooden Chair Design Using High Frequency Heat Molding Technique - Focused on Change of Kindergarten Environment -

  • Ryu, Eun-Seok;Choi, Kyung-Ran;Sung, Yun-Jung
    • Journal of the Korea Furniture Society
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    • v.22 no.3
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    • pp.230-238
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    • 2011
  • Consumers' expenditure is getting larger on children due to their parents' compensation for increase of double-income family life and decrease of birth rate caused by high economic growth. Increase of demand on children items in the market leads the necessity of development of furniture for children. This study is aimed to design children chairs that meet the environment for children. In this study, the age of children is defined to be 5~7 years old. In order to investigate what causes environment change, this study covers roughly change of environment, change of learning program and use of environment-friendly material. In such scope, we drew out the factors that the chairs for children shall be equipped with. Case studies were done through such drawn factors. The scope of the furniture for children is limited to the chairs for children among the ones made in either Korea or overseas. As a result, we could draw out such keyword of the furniture as storage, mobility, environment-friendly, object style image, preferred color, functionality and safety, based on which we could plan the design and make the final result through high frequency round molding manufacturing process.

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A Study on the Production Efficiency Considering the Dimensional Change Rate of Circular Knitted Jacket (환편 니트 재킷의 치수변화율을 고려한 생산효율에 관한 연구)

  • Hwang, Song-Lee;Lee, Jin-Hee
    • Fashion & Textile Research Journal
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    • v.18 no.6
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    • pp.776-786
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    • 2016
  • This study intends to suggest production process of circular knitted jackets and dimensional change data of finished clothes after washing. the study provides pattern design method of circular knitted jackets by applying dimensional change. By doing so, the purpose of this study is to increase production efficiency through accurate order in consideration of loss amount of the fabrics in production. With the three fabric materials selected, this study investigated dimensional change of circular knitted jackets after sewing and washing by varying the parts to be attached to padding cloth and with or without inner lining. As for the fabric F-C (including the spandex, thicker and weightier than the other two fabrics), front width shrunk by 4.6%, which showed the biggest shrinkage among the jackets made of test fabrics. Then it suggested design methods of circular knitted jacket patterns to which dimensional change is applied according to materials, and analyzed the amount of fabric required for production by comparison of the materials. When using the fabric F-C without inner lining, there is big dimensional change and more than double amount of fabric is required. It is expected that the research results will be a basic data for pattern design and production process of circular knitted clothing.

Hydrologic Performance Change of Small Scale Hydro Power Plant with Rainfall Condition Change (강우형태변화에 의한 소수력발전소 수문학적 성능의 변화)

  • Park, Wan-Soon;Lee, Chul-Hyung
    • Journal of the Korean Solar Energy Society
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    • v.29 no.6
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    • pp.56-61
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    • 2009
  • The effects of design parameters for small scale hydro power(SSHP) plants due to climate change have been studied. The model to predict hydrologic performance for SSHP plants is used in this study. The results from analysis far rainfall conditions based on KIER model show that the capacity and load factor of SSHP site had large difference between the period. Especially, the hydrologic performance of SSHP site due to rainfall condition of recent period varied in design flowrate sensitively. However climate change gave small effect in load factor of existing SSHP plant. And also, the methodology represented in this study can be used to decide the primary design specifications of SSHP sites.