• Title/Summary/Keyword: the life cycle

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A Study on the Correlation between Optimal Safety of Structures and Minimization of Life Cycle Cost(LCC) (구조물의 최적안전지수와 생애주기비용의 상관관계에 관한 연구)

  • Bang, Myung-Seok
    • Journal of the Korean Society of Safety
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    • v.29 no.6
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    • pp.94-98
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    • 2014
  • This study was intend to develop the optimal design method of suspension bridge by the reliability analysis based on minimization of life cycle cost(LCC). The reliability analysis was performed considering aleatory uncertainties included in the result of numerical analysis. The optimal design was estimated based on life-cycle cost analysis depending on the result of reliability analysis. As the effect of epistemic uncertainty, the safety index (beta), failure probability (pf) and minimum life cycle cost were random variables. The high-level distributions were generated, from which the critical percentile values were obtained for a conservative bridge design through sensitivity assessment.

Electrode Characteristics of the (Mm)Ni5-Based Hydrogen Storage Alloys ((Mm)Ni5계 수소저장합금의 전극 특성)

  • Han, D.S.;Choi, S.J.;Chang, M.H.;Choi, J.;Park, C.N.
    • Transactions of the Korean hydrogen and new energy society
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    • v.6 no.1
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    • pp.35-41
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    • 1995
  • The MmNi-based alloy electrode was studied for use as a negative electrode in Ni-MH battery. Alloys with $MmNi_5-_xM_x$(M=Co,Al,Mn) composition were synthesized, and their electrode charateristics of activation rate, temperature dependence, electrode capacity and cycle life were investigated. With increasing Al content and decreasing Mn content in the alloys, the discharge capacity increased while the cycle life decreased. As x in $MmNi_5-_xM_x$ increased from 1.5 to 2.0, decreasing the Ni content, the discharge capacity, the low temperature property and the rate capability decreased. However its cycle life was improved. Increasing Co content resulted in a prolonged cycle life and decrease of high rate discharge capacity. It can be concluded that the most promising alloy in view of discharge capacity and cycle life is $MmNi_{3.5}Co_{0.7}Al_{0.5}Mn_{0.3}$.

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A Study on Algorithm of Life Cycle Cost for Improving Reliability in Product Design (제품설계 신뢰성 제고를 위한 LCC의 알고리즘 연구)

  • Kim Dong-Kwan;Jung Soo-Il
    • Journal of the Korea Safety Management & Science
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    • v.7 no.5
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    • pp.155-174
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    • 2005
  • Parametric life-cycle cost(LCC) models have been integrated with traditional design tools, and used in prior work to demonstrate the rapid solution of holistic, analytical tradeoffs between detailed design variations. During early designs stages there may be competing concepts with dramatic differences. Additionally, detailed information is scarce, and decisions must be models. for a diverse range of concepts, and the lack of detailed information make the integration make the integration of traditional LCC models impractical. This paper explores an approximate method for providing preliminary life-cycle cost. Learning algorithms trained using the known characteristics of existing products be approximated quickly during conceptual design without the overhead of defining new models. Artificial neural networks are trained to generalize on product attributes and life cycle cost date from pre-existing LCC studies. The Product attribute data to quickly obtain and LCC for a new and then an application is provided. In additions, the statistical method, called regression analysis, is suggested to predict the LCC. Tests have shown it is possible to predict the life cycle cost, and the comparison results between a learning LCC model and a regression analysis is also shown

Environmental Impact Evaluation for Glass Bottle Recycle using Life Cycle Assessment (LCA를 이용한 유리병 재활용의 환경영향 평가)

  • Baek, Seung-Hyuk;Kim, Hyung-Jin;Kwon, Young-Shik
    • Journal of Environmental Science International
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    • v.23 no.6
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    • pp.1067-1074
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    • 2014
  • Life Cycle Assessment(LCA) has been carried out to evaluate the environmental impacts of glass bottle recycle. The LCA consists of four stages such as Goal and Scope Definition, Life Cycle Inventory(LCI) Analysis, Life Cycle Impact Assessment(LCIA), and Interpretation. The LCI analysis showed that the major input materials were water, materials, sand, and crude oil, whereas the major output ones were wastewater, $CO_2$, and non-hazardous wastes. The LCIA was conducted for the six impact categories including 'Abiotic Resource Depletion', 'Acidification', 'Eutrophication', 'Global Warming', 'Ozone Depletion', and 'Photochemical Oxidant Creation'. As for Abiotic Resource Depletion, Acidification, and Photochemical Oxidant Creation, Bunker fuel oil C and LNG were major effects. As for Eutrophication, electricity and Bunker fuel oil C were major effects. As for Global Warming, electricity and LNG were major effects. As for Ozone Depletion, plate glasses were major effects. Among the six categories, the biggest impact potential was found to be Global Warming as 97% of total, but the rest could be negligible.

Assessment of Greenhouse Gas Emissions from Poultry Enteric Fermentation

  • Wang, Shu-Yin;Huang, Da-Ji
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.6
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    • pp.873-878
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    • 2005
  • Emissions of nitrous oxide (N$_2$O) and methane (CH$_4$) from poultry enteric fermentation were investigated using a respiration chamber. Birds were placed in a respiration chamber for certain intervals during their growing period or for the whole life cycle. The accumulated gas inside the chamber was sampled and analyzed for N$_2$O and CH$_4$ production. A curve for gas production during a life cycle was fitted. The calculated area under the curve estimated the emission factor of poultry enteric fermentation on a life cycle basis (mg bird$^{-1}$ life cycle$^{-1}$). This method can be used to estimate CH$_4$ or N$_2$O emissions from different types of avian species taking into account factors such as diet, season or thermal effects. The CH$_4$/N$_2$O emission factors estimated for commercial broiler chickens, Taiwan country chickens and White Roman Geese were 15.87/0.03, 84.8/16.4 and 1,500/49 (mg bird$^{-1}$ life cycle$^{-1}$), respectively, while the calculated CH$_4$/N$_2$O emission from enteric fermentations were 3.03/0.006, 14.73/2.84 and 9.5/0.31 (Mg year$^{-1}$), respectively in Taiwan in the year of 2000. The described method is applicable to most poultry species and the reported emission factors were applicable to meat type poultry only.

Study on Compound Humidifier Employing UV-LED using Environmental Life Cycle Assessment (환경전과정평가에 기반한 UV-LED 를 사용한 복합식 가습기에 관한 연구)

  • Choi, Won-Sik;Park, Si-Hyun;Lee, Si-Wang;Jung, Young-Mi;Yi, Hwa-Cho
    • Journal of the Korean Society for Precision Engineering
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    • v.29 no.9
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    • pp.931-937
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    • 2012
  • In this study, we assessed environmental impacts of compound humidifiers using environmental life cycle assessment and presented the ways to improvements in energy consumption of them. We found eco-design parameters and $CO_2$-eq emissions in each stage of raw material acquisition, manufacturing, transportation, use and disuse in life cycle of the compound humidifiers. The highest $CO_2$ emission is found to be in the stage of use among all stages of life cycle, which is mainly due to power consumption in thermal heating of heating coil for sterilization during humidification. The power consumption and $CO_2$ emission in the stage of use can be reduced to 1/4 and 1/3 at the highest estimate through improvement of sterilization method, respectively. We suggested the replacement of conventional thermal heating coil by ultra violet light-emitting diodes (UV-LED) for sterilization and then presented the experimental results on the sterilization effects of UV-LEDs.

Eco-Friendly Mechanical Design of Touch-Screen Monitor Stand through Life-Cycle Assessment(LCA) (전과정평가(LCA)에 기반한 터치스크린 모니터 스탠드의 친환경적 기구설계)

  • Yi, Hwa-Cho;Jang, Woon-Geun;Han, Hoon;Jo, Young-Rae;Jeon, Chan-gon
    • Journal of the Korean Society of Industry Convergence
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    • v.15 no.4
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    • pp.117-124
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    • 2012
  • Recent years, many industries acknowledge that environmental substantiality of products must be an essential role and it is one of the major importances for industries to consider the environmental impacts of products at the early stages of product development. This study investigated eco-design parameters and $CO_2-eq$. emissions in each stage of raw material acquisition, manufacturing, transportation, use and disuse in life cycle of touch monitor stand based on Eco-Design. In this study, to fulfill of Eco-Design, the environmental impact assessment of through LCA(Life cycle assessment) was carried out with benchmarking monitor stand and we suggested the direction of new design of touch monitor stand mechanism based on eco-friendly considerations. New design based on LCT(Life Cycle Thinking) showed that the following eco-friendly considerations at the early stage of design to be helpful to reduce GWP(Global Warming Potential) [kg $CO_2-eq$.] in new monitor stand development and it is necessary for Eco-Design process of the product.

Life Cycle Cost Analysis for Design of Buildings based on the Lifetime Risk (생애 위험도기반 건축물의 설계단계 생애주기비용 분석 방법)

  • Baek, Byung-Hoon;Cho, Choong-Yeon
    • Korean Journal of Construction Engineering and Management
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    • v.15 no.3
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    • pp.113-119
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    • 2014
  • Recently, the demand on the practical application of life-cycle cost effectiveness for design and rehabilitation of structure is rapidly growing unprecedently in engineering practice. Accordingly, in the 21st century, it is almost obvious that life-cycle cost together with value engineering will become a new paradigm for all engineering decision problems in practice. However, in spite of impressive progress in the researches on the LCC, the most researches have only focused on the Deterministic or Probabilistic LCC analysis approach (Level-1 LCC Model) at design stage. Thus, the goal of this study is to develop a practical and realistic methodology for the Lifetime risk based Life-Cycle Cost (LCC)-effective optimum decision-making at design stage.

Personal Information life Cycle Model Considering the Learning Cha racteristics of Artificial Intelligence (인공지능의 학습 특성을 고려한 개인정보 라이프 사이클 모델)

  • Jaeyoung Jang;Jong-Min Kim
    • Convergence Security Journal
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    • v.24 no.2
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    • pp.47-53
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    • 2024
  • The traditional personal information life cycle model, primarily tailored to conventional systems, is inherently unsuitable for comprehending the nuances of personal information flow within artificial intelligence frameworks and for formulating effective protective measures. Therefore, this study endeavors to introduce a personal information life cycle model specifically designed for artificial intelligence (AI). This paper presents a personal information life cycle model suitable for artificial intelligence, which includes the stages of collection, retention, learning, use, and destruction/suspension, along with the re-learning process for destruction/suspension. Subsequently, we compare the performance of these existing models (such aspersonal information impact assessment and the ISMS-P model) with the newly proposed model. This underscores the superiority of our proposed model in comprehensively understanding the personal information flow in AI and establishing robust protective measures.

A Study on the Analysis and Evaluation for the Life-cycle Model of Digital Content (디지털 콘텐츠 수명주기 모델 분석 및 평가에 관한 연구)

  • Kwak, Seung-Jin;Sung, Won-Kyung;Bae, Kyung-Jae
    • Journal of Information Management
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    • v.42 no.1
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    • pp.25-46
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    • 2011
  • This study aims to identify the core life-cycle elements for archiving digital content through analyzing the existing digital content life-cycle models and suggest the remedies for management the digital content of KISTI after a comparative study. As a result, the 10 core life-cycle categories consisted of 31 small elements were defined. Furthermore, the recommendations that digital content archiving should be set as a critical mission and archiving policy should be prepared in KISTI were proved.