• Title/Summary/Keyword: Long cycle life

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A Study on the Model Improvement of Korean Industrial Standards-Quality Excellence Index(KS-QEI) (KS제품 품질우수성지수 모델 개선 방안에 관한 연구)

  • Kim, Tai-Kyoo;Kim, Myung Joon
    • Journal of Korean Society for Quality Management
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    • v.41 no.3
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    • pp.327-335
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    • 2013
  • Purpose: The purpose of this study is to suggest the modified 'Korean Standard-Quality Excellence Index' model and analyze the improvement effect with survey data by comparing the properness between current and suggested model result. Methods: The collected data through the survey were analyzed using paired t-test and unbalanced ANOVA method for testing the consistency of two customer satisfaction evaluating categories and comparing the current model to suggested model for confirming the improvement of performance. Results: The statistical analysis result shows that adjusted model using prior information improves the consistency between two customer satisfaction in case of short life-cycle product. Also long life-cycle product case, the result shows difference gap decreasing with same direction. Conclusion: Considering statistical model for QEI reflecting the characteristic of product group such as life cycle seems to be meaningful. Since index may be compared yearly base for checking the trend, careful approaching without big change should be considered for application.

Comparative Analysis of SOx Emission-Compliant Options for Marine Vessels from Environmental Perspective

  • Jeong, Byongug
    • Journal of Power System Engineering
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    • v.22 no.1
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    • pp.72-78
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    • 2018
  • With growing concerns over air pollutions attributed to shipping activities, the international maritime organization has enacted a series of stringent regulations. In particular, MARPOL Annex IV Reg. 16 requires sulfur contents from exhaust gases of marine engines to be progressively reduced. To comply with this regulation, three feasible options have been introduced: using LNG as a marine fuel, using heavy fuel oil with the scrubber system, and using the marine gas oil (a type of low sulfur fuel oil). For the objectives of this paper, the holistic environmental impacts pertinent to these options were investigated and compared in ways that the flows of energy and emission were tracked and quantified through the life cycle of the ship. Research findings obtained from a case study with a large bulk carrier showed that the use of the scrubber system to purify heavy fuel oil would produce relatively fewer amounts of emissions attributing to global warming than other two options. On the other than, the use of LNG would be the way to operate the ship in a cleaner way in terms of reducing the acidification, eutrophication, and photochemical effects. Throughout the analysis, the excellence of life cycle assessment was proven to shift the environmental impact of marine systems from the short-term view to the long-term one.

The Investment Always Will Get Gains? Advertising Expenditure and Enterprise Performance Based on Corporate Life Cycle

  • Li, Liang;Amine, Bouirig;Pang, Yuxin;Jiang, Minxing
    • Asia Pacific Journal of Business Review
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    • v.6 no.2
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    • pp.61-76
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    • 2022
  • Based on the concept of advertising expenditure, manufacturing firm performance, and enterprise life cycle, this research conducts the listed Chinese manufacturing listed in 2016-2018 as the research sampling and divides these listed companies into three periods: growth, maturity, and decline. Next, this paper conducts empirical research from three aspects: advertising expenditure or investment and manufacturing firm performance, lag effect of advertising expenditure, and outcome effect and lag effect of advertising investment. It is found that in different stages of manufacturing enterprises, different advertising expenditures will have different impacts on the performance of manufacturing enterprises. In the growth stage, the advertising investment of manufacturing enterprises will significantly affect the performance results of the current period, and there will be the long-term lag effect. In contrast, the mature stage of enterprises' advertising investment has a shorter period of lag effect, while in the recession stage, the mature stage of manufacturing enterprises' advertising investment will have a shorter period of lag effect. The empirical results are not significant. This study provides a reference for manufacturing enterprises in different stages in the decision-making of advertising investment.

A Study on the Analysis of Carbon Emissions by Transportation Distance of Building Materials (건축자재 운송거리에 따른 탄소배출량 분석에 관한 연구)

  • Kim, Hyeon-Suk;Tae, Sung-Ho;Lim, Hyo-Jin;Jang, Hyeong-Jae;Lee, Chung-Won
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2022.11a
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    • pp.125-126
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    • 2022
  • As environmental problems around the world become serious, Korea has also raised the greenhouse gas reduction in the building sector to 32.8% compared to 2018, and efforts to reduce carbon in buildings are expanding. Recently, research is being actively conducted to reduce carbon in the long term by expanding the scope of greenhouse gas indirect emissions (Scope3), and even within the domestic Green Standard for Energy and Environmental Design(G-SEED) by quantitatively evaluating the environmental impact of buildings during the entire life cycle. However, it is difficult to accurately evaluate the carbon emission of the transportation process by assuming the material transport distance in the evaluation of the Life Cycle Assessment(LCA). Therefore, in this study, the main building materials of the building were selected through case evaluation and the carbon emission of the material transport process was derived based on the actual transport distance, and this was compared and analyzed with the theoretical LCA results.

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Development of Tunnel Asset Management (TAM) Program

  • Hamed Zamenian;Dae-Hyun (Dan) Koo
    • International conference on construction engineering and project management
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    • 2013.01a
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    • pp.576-582
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    • 2013
  • Typical highway infrastructure systems include roadway pavement, drainage systems, tunneling, and other hardware components such as guardrails, traffic signs, and lighting. Tunnels in a highway system have provided significant advantages to overcoming various natural challenges including crossing underneath bodies of water or through mountainous areas. While only a few tunnel failure cases have been reported, the failure rate is likely to increase as these assets age and because agencies have not emphasized tunneling asset management. A tunnel system undergoes a deterioration life cycle pattern that is similar to other infrastructure systems. There are very few agencies in the United States implementing comprehensive tunnel asset management programs. While current tunnel asset management programs focus on inspection, maintenance, and operation safety, there is an increasing need for the development of a comprehensive life cycle tunnel asset management program. This paper describes a conceptual framework for a comprehensive tunnel asset management program. The framework consists of three basic phases including a strategic plan, a tactical plan, and an operational plan to provide better information to the decision makers. The strategic plan is a basic long term approach of tunnel asset management. The tactical plan determines specific objectives and the operational plan actually applies asset management objectives in practice. The information includes operational condition, structural condition, efficiency of the system, emergency response, and life cycle cost analysis for tunnel capital improvement project planning.

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A Study on the Life Cycle Cost Calculation of the Railroad Vehicle Based on the Maintenance Information (철도차량 유지보수정보를 이용한 수명주기비용 계산 연구)

  • Kim, Jae-Hoon;Jun, Hyun-Kyu;Park, Jun-Seo;Jeong, Hyun-Yong
    • Journal of the Korean Society for Railway
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    • v.12 no.1
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    • pp.88-94
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    • 2009
  • Life cycle costing is one of the most effective approaches for the cost analysis of long-life products such as the railroad vehicle. Life cycle costing includes the cost of concept design, development, manufacture, operation, maintenance and disposal. Especially, life cycle costing in the railroad industry has been focused on the maintenance cost. In this paper, the standard, guide and maintenance information of railroad vehicle were investigated, and the unique corrective and preventive maintenance templates of railroad vehicle were proposed. Maintenance cost of an auxiliary power supply system of EMU was predicted by using the proposed templates. The results show that the preventive maintenance, PM, cost is much higher compare to corrective maintenance, CM, cost because of daily and monthly maintenance tasks which require lots of labor work. It is expected that these templates can help railroad operators make maintenance strategies with consideration of the cost parameter.

The Study on the formal durability of consumer products - focused on the cases of long-selling products (제품조형의 내구적 속성에 관한 연구 -장기간 판매 제품의 사례를 중심으로)

  • 조영식;조민정
    • Archives of design research
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    • v.12 no.2
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    • pp.97-106
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    • 1999
  • The whole crisis of human being derived from environmental pollution has changed the human -centered paradigm into the ecological paradigm based on the harmony of human and nature, which have made it inevitable for designers to participate in the environmental problem-solving. In the line of this sense, it is necessary for designers to recognize the social and ethical responsibility for environmental pollution and to change into the designing for environment, not for sale itself. In accord with the context above, the purpose of this study is to suggest some clues for resolving environmental problems with the analysis of design for long-selling product, as we call, product durability analysis. That is, this study is under some assumptions that designing durable product and durable product itself are able to extend a product life cycle, delay a product disusing, reduce a rash development competition for new product among companies, mitigate consumption-oriented attitude of consumers, eliminate a waste of resources, and go far toward the environmental problem solving.

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Life-Cycle Cost-Effective Optimum Design of Steel Bridges Considering Environmental Stressors (환경영향인자를 고려한 강교의 생애주기비용 최적설계)

  • Lee, Kwang Min;Cho, Hyo Nam;Cha, Cheol Jun
    • Journal of Korean Society of Steel Construction
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    • v.17 no.2 s.75
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    • pp.227-241
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    • 2005
  • This paper presents a practical and realistic Life-Cycle Cost (LCC) optimum design methodology for steel bridges considering the long-term effect of environmental stressors such as corrosion and heavy truck traffics on bridge reliability. 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, which takes into consideration 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 (40m+50m+40m=130m). Various sensitivity analyses 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 volume of truck traffic significantly influence the LCC-effective optimum design of steel bridges. Thus, these conditions should be considered as crucial parameters for the optimum LCC-effective design.

Development of Long-Life Asphalt Pavements Method Using High Modulus Asphalt Mixes (고강성 기층재를 적용한 장수명 아스팔트포장 공법 개발)

  • Lee Jung-Hun;Lee Hyun-Jong
    • International Journal of Highway Engineering
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    • v.8 no.3 s.29
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    • pp.49-61
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    • 2006
  • This study suggests long-life asphalt pavement method which can save maintenance cost by increasing the design and performance period of pavements. The high modulus asphalt binder developed and then various physical tests are performed. Laboratory performance tests and accelerated pavement test are conducted for the high modulus and conventional mixtures. The test results show that dynamic modulus values of high modulus mixtures are higher than those of the conventional mixtures, The high modulus mixtures yield better fatigue, rutting and moisture damage performance than conventional mixtures. Structural analysis is performed and a database is built up for long life asphalt pavement design. Pavement response model is developed through a multiple regression analysis program, SPSS using the database. A design software for the long life pavements is developed based on the pavement response model and laboratory and field performance tests results. In addition, optimum pavement sections and materials are suggested. The suggested AC thickness of long life asphalt pavement is 29cm. A Life cycle cost analysis(LCCA) is conducted to check the economical efficiency of the long life pavement section. The LCCA result shows that initial construction costs of long life and conventional pavements are almost equal, but long life pavement is more profitable in terms of the LCCA.

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Catalytic effects of heteroatom-rich carbon-based freestanding paper with high active-surface area for vanadium redox flow batteries

  • Lee, Min Eui;Kwak, Hyo Won;Jin, Hyoung-Joon
    • Carbon letters
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    • v.28
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    • pp.105-110
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    • 2018
  • Owing to their scalability, flexible operation, and long cycle life, vanadium redox flow batteries (VRFBs) have gained immense attention over the past few years. However, the VRFBs suffer from significant polarization, which decreases their cell efficiency. The activation polarization occurring during vanadium redox reactions greatly affects the overall performance of VRFBs. Therefore, it is imperative to develop electrodes with numerous catalytic sites and a long cycle life. In this study, we synthesized heteroatom-rich carbon-based freestanding papers (H-CFPs) by a facile dispersion and filtration process. The H-CFPs exhibited high specific surface area (${\sim}820m^2g^{-1}$) along with a number of redox-active heteroatoms (such as oxygen and nitrogen) and showed high catalytic activity for vanadium redox reactions. The H-CFP electrodes showed excellent electrochemical performance. They showed low anodic and cathodic peak potential separation (${\Delta}E_p$) values of ~120 mV (positive electrolyte) and ~124 mV (negative electrolyte) in cyclic voltammetry conducted at a scan rate of $5mV\;s^{-1}$. Hence, the H-CFP-based VRFBs showed significantly reduced polarization.