• Title/Summary/Keyword: LIFE CYCLE

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Lifetime Reliability Based Life-Cycle Cost-Effective Optimum Design of Steel Bridges (생애 신뢰성에 기초한 강교의 LCC최적설계)

  • Lee, Kwang Min;Cho, Hyo Nam;Cha, CheolJun;Kim, Seong Hun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.1A
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    • pp.75-89
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    • 2006
  • This paper presents a practical and realistic Life-Cycle Cost (LCC) optimum design methodology of steel bridges considering time effect of bridge reliability under environmental stressors such as corrosion and heavy truck traffics. The LCC functions considered in the LCC optimization consist of initial cost, expected life-cycle maintenance cost and expected life-cycle rehabilitation costs including repair/replacement costs, loss of contents or fatality and injury losses, road user costs, and indirect socio-economic losses. For the assessment of the life-cycle rehabilitation costs, the annual probability of failure which depends upon the prior and updated load and resistance histories should be accounted for. For the purpose, Nowak live load model and a modified corrosion propagation model considering corrosion initiation, corrosion rate, and repainting effect are adopted in this study. The proposed methodology is applied to the LCC optimum design problem of an actual steel box girder bridge with 3 continuous spans (40 m+50 m+40 m=130 m), and various sensitivity analyses of types of steel, local corrosion environments, average daily traffic volume, and discount rates are performed to investigate the effects of various design parameters and conditions on the LCC-effectiveness. From the numerical investigation, it has been observed that local corrosion environments and the number of truck traffics significantly influence the LCC-effective optimum design of steel bridges, and thus realized that these conditions should be considered as crucial parameters for the optimum LCC-effective design.

A Study on Elemental Technology Identification of Sound Data for Audio Forensics (오디오 포렌식을 위한 소리 데이터의 요소 기술 식별 연구)

  • Hyejin Ryu;Ah-hyun Park;Sungkyun Jung;Doowon Jeong
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.34 no.1
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    • pp.115-127
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    • 2024
  • The recent increase in digital audio media has greatly expanded the size and diversity of sound data, which has increased the importance of sound data analysis in the digital forensics process. However, the lack of standardized procedures and guidelines for sound data analysis has caused problems with the consistency and reliability of analysis results. The digital environment includes a wide variety of audio formats and recording conditions, but current audio forensic methodologies do not adequately reflect this diversity. Therefore, this study identifies Life-Cycle-based sound data elemental technologies and provides overall guidelines for sound data analysis so that effective analysis can be performed in all situations. Furthermore, the identified elemental technologies were analyzed for use in the development of digital forensic techniques for sound data. To demonstrate the effectiveness of the life-cycle-based sound data elemental technology identification system presented in this study, a case study on the process of developing an emergency retrieval technology based on sound data is presented. Through this case study, we confirmed that the elemental technologies identified based on the Life-Cycle in the process of developing digital forensic technology for sound data ensure the quality and consistency of data analysis and enable efficient sound data analysis.

Down-regulation of the cyclin E1 oncogene expression by microRNA-16-1 induces cell cycle arrest in human cancer cells

  • Wang, Fu;Fu, Xiang-Dong;Zhou, Yu;Zhang, Yi
    • BMB Reports
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    • v.42 no.11
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    • pp.725-730
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    • 2009
  • Cyclin E1 (CCNE1), a positive regulator of the cell cycle, controls the transition of cells from G1 to S phase. In numerous human tumors, however, CCNE1 expression is frequently dysregulated, while the mechanism leading to its dysregulation remains incompletely defined. Herein, we showed that CCNE1 expression was subject to post-transcriptional regulation by a microRNA miR-16-1. This was evident at protein level of CCNE1 as well as its mRNA level. Further evident by dual luciferase reporter assay revealed that two evolutionary conserved binding sites on 3' UTR of CCNE1 were the direct functional target sites. Moreover, we showed that miR-16-1 induced G0/G1 cell cycle arrest by targeting CCNE1 and siRNA against CCNE1 partially phenocopied miR-16-1-induced cell cycle phenotype whereas substantially rescued anti-miR-16-1- induced phenotype. Together, all these results demonstrate that miR-16-1 plays a vital role in modulating cellular process in human cancers and indicate the therapeutic potential of miR-16-1 in cancer therapy.

A Study on the Characteristics of Environmental Impact with the Seat Material of Electric Motor Unit (EMU) (전동차 의자의 재질에 따른 환경부하 특성에 관한 연구)

  • Lee, Jae-Young;Kim, Bo-Kyong;Chun, Yoon-Young;Kim, Yong-Ki
    • Journal of the Korean Society for Railway
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    • v.9 no.5 s.36
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    • pp.524-531
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    • 2006
  • Environmental problem is one of important global issues. Transportations are main pollutant emission sources. Although railroad is stilt an environmental-friendly transportation, its environmental impact has been increased continuously. Especially, because a large amount of environmental impact is released from vehicles and facilities, it is necessary to assess and to reduce their environmental impact. Life cycle assessment (LCA) is a representative method which can evaluate environment impact through the whole life cycle of a product or a process. In this study, the environmental impact of seat in the electric motor unit (EMU) was analyzed quantitatively with its material using lift cycle assessment (LCA). As a result, the characteristics of environmental impact were investigated differently with the material of seat. Among ten impact categories, the seat with aluminum and FRP showed the highest ozone depletion (OD). On the other hand, in the seat with stainless steel and plastic, fresh water aquatic ecotoxicity (FAET) and marine water aquatic ecotoxicity (MAET) were high relatively. Therefore, the parts of EMU must be selected considering the characteristics of environmental impact in future.

Analysis of the Hanwoo Rasing Cycle Using Sine Function (싸인함수를 이용한 한우 사육두수 예측)

  • Jeon, Sang-Gon
    • Journal of agriculture & life science
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    • v.46 no.6
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    • pp.197-205
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    • 2012
  • This paper analyzes the beef cycle and forecasts the number of Hanwoo. This study uses Sine function for this purpose. Data shows that beef cycle varies from five to twelve years and the cycle becomes longer as time passes. The adjusted $R^2$ of the estimated model is 0.95. The forecasted value based on this model for the number of Hanwoo is 1.6-1.8 million heads in lower bound and 3.2-3.7 million heads in upper bound, where the peak points are slightly different according to cycles. These predicted values imply the instability of number of Hanwoo and corresponding farm income, so we have to prepare adequate policies to cope with it.

A Study on the Performance Prediction Model for Life Cycle Maintenance of Reservoir (저수지 생애주기 유지관리를 위한 성능저하예측 모델 연구)

  • Lee, Huseok;Kim, Ran-Ha;Cho, Choong-Yuen
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.1
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    • pp.568-574
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    • 2021
  • According to the Framework Act on Sustainable Infrastructure Management, which has been enforced since 2020, reservoirs should be managed to minimize life cycle costs caused by aging through preemptive management such as systematic maintenance and performance improvement. For maintenance in consideration of the life cycle, it is essential to derive the end of life due to continuous performance degradation as the common period increases. For this purpose, it is necessary to develop a performance-predicting model for reservoirs. In this study, a reservoir was divided into main complex facilities to develop a model for the maintenance of the life cycle. A model was developed for each facility. For model development, maintenance information data were collected under management by the Rural Community Corporation. The data available for model development were selected by analyzing the collected data. The developed model was used to predict the expected life expectancy of the reservoir in the current maintenance system and the expected life expectancy in the case of no action. By using the developed model, it is expected that it will be possible to support decision making in operation management and maintenance while considering the life cycle of the reservoir.

$CO_2$ Reduction Effect Analysis of Modal Shift from Road to Rail using Life Cycle Thinking (전과정을 고려한 도로-철도 Modal Shift $CO_2$ 저감효과 분석)

  • Kim, Cho-Young;Lee, Cheul-Kyu;Choi, Yo-Han;Lee, Kun-Mo
    • Proceedings of the KSR Conference
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    • 2011.10a
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    • pp.2921-2927
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    • 2011
  • Modal Shift from road to rail has been adapted in several countries as one of effective ways of reducing $CO_2$ emissions caused by transport. Generally, effect analysis of $CO_2$ reduction toward modal shift is calculated mainly from use stage and less consideration from other stages of life cycle, even though, in some case of modal shift needs that new line construction or new vehicle manufacturing. In this study, modal shift effect analysis is performed with considering construction, manufacturing vehicle and use stage. As a result we can get total $CO_2$ reduction effect using life cycle thinking and check the necessity of including other life cycle stage not only considering use stage. In conclusion, there is no $CO_2$ reduction effect if the reduction amount of $CO_2$ in use stage is not bigger than allocated annual amount of $CO_2$ in construction and manufacturing vehicle stage. According to this fact, analysing $CO_2$ reduction effect of Modal Shift should be considered not only the use stage.

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Practical Application of Life-Cycle Cost Effective Design and Rehabilitation of Bridges

  • Cho, HyoNam;Park, KyungHoon;Hwang, YoonGoog;Lee, KwangMin
    • Corrosion Science and Technology
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    • v.3 no.2
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    • pp.72-80
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    • 2004
  • Recently, the demand on the practical application of life-cycle cost effective design and rehabilitation of bridges is rapidly growing in civil engineering practice. However, in spite of impressive progress in the researches on the Life-Cycle Cost (LCC), the most researches have only focused on the theoretical point but did not fully incorporate the critical issues for the practical implementation. Thus, this paper is intended to suggest a systemic integrated approach to the practical application of various LCC methodologies for the design and rehabilitation of bridges, For that purpose, hierarchical definitions of LCC models are presented to categorize the approach of LCC assessment applicable for the practical implementation. And then, an integrated LCC system model is introduced with an emphasis on data uncertainty assessment and user-friendly knowledge-based database for its successful implementation. Finally, in order to demonstrate the LCC effectiveness for design and rehabilitation of real bridge structures, illustrative examples are discussed.

Exploring Capabilities of BIM Tools for Housing Refurbishment in the UK

  • Kim, Ki Pyung;Park, Kenneth S
    • Journal of KIBIM
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    • v.6 no.4
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    • pp.9-17
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    • 2016
  • Currently whole-house refurbishment for substantial energy efficiency improvement of existing housing stock is needed to achieve the targeted 80% CO2 emission reduction. As whole-house refurbishment requires a larger capital investment for lower CO2 emission, the simultaneous use of Life Cycle Costing (LCC) and Life Cycle Assessment (LCA) methodologies are recommended to generate affordable refurbishment solutions. However, two methodologies are difficult to use due to a lack of proper LCC and LCA datasets. As a response to the current problems, many researchers explore potentials in Building Information Modelling (BIM) to improve current construction practice. As a result, a BIM tool - IES IMPACT (Integrated Material Profile And Costing Tool) - has been introduced to the UK construction industry for simultaneous calculation of LCC and LCA. Thus, this research aims at examining the capability and limitation of the IES VE/IMPACT as a BIM tool for whole-house refurbishment. This research reveals that the IES VE/IMPACT is feasible for whole-house refurbishment by providing LCC and LCA information simultaneously for informed decision on refurbishment solution selection. This research shed lights on the current problems lying on the data exchange between two different BIM tools. It is revealed that additional efforts from construction professionals and industry are required to make reliable BIM objects library with LCC and LCA datasets.

The Effects of Subjective Knowledge on Information Search as Related to a Consumer's Life Cycle (의류제품 소비자의 생활주기에 따른 주관적 지식이 정보탐색에 미치는 영향)

  • Hwang, Jeong-In;Park, Jae-Ok
    • Journal of the Korean Home Economics Association
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    • v.48 no.9
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    • pp.41-54
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    • 2010
  • This study attempted to determine how the subjective knowledge related to a consumer's life cycle influences their information search in the decision making process. The data was collected using a total of 349 questionnaires for the final analysis of this study. SPSS 12.0 for windows was used for the data analysis and the detailed analyses included descriptive analysis, factor analysis, reliability tests, one way ANOVA, multiple regression analysis and t-tests. The results of this study showed that there are differences in the subdivisions of subjective knowledge of apparel according to the consumer's life cycle and there is a difference in the types of information searches according to the consumer's subjective knowledge, and the subdivisions of subjective knowledge of the consumers influence their information search. This study showed that although it affected the internal search, the media search, and the store search, it did not influence the personal search in the decision making process.