• Title/Summary/Keyword: Life-cycle cost

Search Result 1,050, Processing Time 0.026 seconds

A Review on Prognostics of Polymer Electrolyte Fuel Cells (고분자전해질 연료전지 예지 진단 기술)

  • LEE, WON-YONG;KIM, MINJIN;OH, HWANYEONG;SOHN, YOUNG-JUN;KIM, SEUNG-GON
    • Transactions of the Korean hydrogen and new energy society
    • /
    • v.29 no.4
    • /
    • pp.339-356
    • /
    • 2018
  • Although fuel cell systems have advantages in terms of electric efficiency and environmental impact compared with conventional power systems, fuel cell systems have not been deployed widely due to their low reliability and high price. In order to guarantee the lifetime of 10 years, which is the commercialization goal of Polymer electrolyte fuel cells (PEFCs), it is necessary to improve durability and reliability through optimized operation and maintenance technologies. Due to the complexity of components and their degradation phenomena, it's not easy to develop and apply the diagnose and prognostic methodologies for PEFCs. The purpose of the paper is to show the current state on PEFC prognostic technology for condition based maintenance. For the prognostic of PEFCs, the model driven method, the data-driven, and the hybrid method can be applied. The methods reviewed in this paper can contribute to the development of technologies to reduce the life cycle cost of fuel cells and increase the reliability through prognostics-based health management system.

A Sales Promotion Strategy for Casual Korean Traditional Clothes Using Database Marketing (데이터베이스 마케팅을 활용한 생활한복의 구매촉진 방안)

  • 임영미;이은경
    • Journal of the Korean Society of Costume
    • /
    • v.51 no.5
    • /
    • pp.29-43
    • /
    • 2001
  • Database marketing is a series of marketing activities based on the customer database for increasing the customer's life-time value. In this thesis. we applied database marketing to the sales promotional strategies of Casual Korean Traditional Clothes to activate wearing of Casual Korean Traditional Clothes. To achieve this goal, we surveyed the consciousness of wearing and purchases for Casual Korean Traditional Clothes. and extract information that can be utilized in the sales promotional strategies. According to the result, the proposed sales promotional strategies for Casual Korean Traditional Clothes are summarized as follows : (1) Useful information for the customer should be stored in the database and utilized in the marketing. (2) It is necessary to shorten the cycle of repeated purchases by emphasizing daily-life clothing of Casual Korean Traditional Clothes especially for the aged 20-40. (3) Since Casual Korean Traditional Clothes are usually weared as a ceremonial clothes in the fall, direct mail, fashion show, and advertising in the mass media should be concentrated on this season. (4) Value-added marketing should be derived by cross-selling of items harmonized with Casual Korean Traditional Clothes. (5) To guarantee fixed customers and increased usage of Casual Korean Traditional Clothes, - give point score, discount, or selling on an installment basis for the customers who use credit cards or department cards. - select privileged customers by analyzing purchase history and provide multiple services for these customers. - let the customers rent Casual Korean Traditional Clothes in an appropriate cost, and make customer cards for the construction of elaborated customer database. (6) To increase the acknowledgement of Casual Korean Traditional Clothes, not only Persistent publicity, but also fashion show, visual merchandising, and advertisement in mass media should be conducted as well.

  • PDF

Maintenance Performance Improvement Method of the Buildings in Design Phase (설계단계에서 건축물의 유지관리성능 향상 방안;건축계획분야를 중심으로)

  • Yoon, Ho-Bin;Kim, Seung-Jin;Lee, Chan-Sik
    • Proceedings of the Korean Institute Of Construction Engineering and Management
    • /
    • 2006.11a
    • /
    • pp.692-697
    • /
    • 2006
  • The importance about the maintenance consideration of the building has a great impact and regarding the life continuation of the building the many interest is becoming intensively. The housing lot of the heart of urban at the capital region has insufficient recently and the construction of the ground complex building in solution for the insufficiency is increasing at the rapid pace. The ground complex building is brings the maximization of land use from inside the site, but maintenance consideration phase is caused by administration cost share and administration bound limit where person is concerned for a many problem point it contains. The objective of the present paper is that the building is maintain an efficiency initially and is improve in order to develop guide line for a maintenance consideration improvement from design phase. According as literature research and question research is enforce, the paper is escape problem point the maintenance consideration and is bring up guide line for the architectural plan field and the maintenance consideration improvement of the building. Result of the study is expected a help in maintenance consideration improvement during life cycle of the building

  • PDF

A Theoretical Review on the Intangible Assets Valuation Techniques of Income Approach (무형자산평가에 관한 이론적 고찰 - 소득접근법의 평가기법을 중심으로 -)

  • Ahn, Jeong-Keun
    • Journal of Cadastre & Land InformatiX
    • /
    • v.45 no.1
    • /
    • pp.207-224
    • /
    • 2015
  • The purpose of this study is to review the various valuation techniques of intangible assets. The value of intangible asset by the income approach can be measured as the present value of the economic benefit over the intangible asset's remaining useful life. The typical methods used in intangible asset economic income projections include extrapolation method, life cycle analyses, sensitivity analyses, simulation analyses, judgment method, and tabula rasa method. There are several methods available for estimating capitalization rates and discount rates for intangible asset, in which we have discussed market extraction method, capital asset pricing model, built-up method, discounted cash flow model, and weighted average cost of capital method. As the capitalization methods for intangible asset, relief-from-royalty method, excess earnings capitalization method, profit split method, residual from business enterprise method, postulated loss of income method and so on have been reviewed.

Mid-term Requirement of 'Elements of Depot Maintenance' draft (창정비요소 개발 과정정립을 통한 창정비요소개발 발전을 위한 제언)

  • Ahn, Jung-Jun;Kim, Jong-Jin
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.19 no.3
    • /
    • pp.638-647
    • /
    • 2018
  • We have to prepare for the existing threats from North Korea and potential threats in the future. It is important to utilize our resources as effectively as possible to build military power that brings victory in a war. Based on a sustainable required operational capability, weapons systems at the acquisition stage need to maintain a combat-readiness posture and ensure operational sustainability. To achieve this, establishment of procedures that develop elements of depot maintenance at the beginning, which enables economical and effective depot maintenance during that stage, is essential. First, the requirement paper needs to develop the concept of the depot maintenance requirement through the pre-study outlined by this paper. Second, at the system development stage, a Development Plan of Depot Maintenance draft should be proposed. This is the initial paper that can develop the elements of depot maintenance, and it should be verified by a field test. Third, each force's logistics command should write a Depot Maintenance Direction draft and a Mid-term Requirement of Elements of Depot Maintenance draft with the proven Development Plan of Depot Maintenance draft. Also, the verified paper needs to be realized and renewed by the time the Requirement of Elements of Depot Maintenance draft is completed. In conclusion, the procedures explained above will contribute to build an economical and effective military power in a reality faced with a resource shortage and threats from the enemy.

The Study on Frameworks of Valuation Models for the Contents of Science and Technology Information (과학기술정보 콘텐츠의 가치평가모형 프레임워크 연구)

  • Sung, Tae-Eung;Jun, Seung-Pyo;Byun, Jeongeun;Park, Hyun-Woo
    • The Journal of the Korea Contents Association
    • /
    • v.16 no.11
    • /
    • pp.421-433
    • /
    • 2016
  • Recently, although the interest in transfer and transactions of intangible assets increases, there is no valuation model to objectively assess market value of knowledge and information contents such as electronic databases and the necessity of researches associated is brought up. Therefore, the present study proposes valuation models so as to utilize as objective reference information in the contents market of intangible assets, by assessing the market value of science and technology information contents including patents, academic papers and reports. First, we look into application methods of calculating cash flows by content types out of key variables which has been applied to the present technology valuation, and in case of patents we propose valuation methods based on concepts which are applied in the present technology valuation. Next, in case of both papers and reports, in order to reflect the characteristics of these contents we newly propose qualitative valuation methods which are adjustable based on both technology innovation and market demands indices while estimating the economic life cycle of the technology, and also present the input cost-based calculation method as the calculation method of cash flows. Throughout the study, we could establish frameworks by technology fields and business models applicable such as copyright licensing, transactions of individual science and technology information contents, and expect that more objective and reasonable assessment of content values is accessible.

Translation of 3D CAD Data to X3D Dataset Maintaining the Product Structure (3차원 CAD 데이터의 제품구조를 포함하는 X3D 기반 데이터로의 변환 기법)

  • Cho, Gui-Mok;Hwang, Jin-Sang;Kim, Young-Kuk
    • The KIPS Transactions:PartA
    • /
    • v.18A no.3
    • /
    • pp.81-92
    • /
    • 2011
  • There has been a number of attempts to apply 3D CAD data created in the design stage of product life cycle to various applications of the other stages in related industries. But, 3D CAD data requires a large amount of computing resources for data processing, and it is not suitable for post applications such as distributed collaboration, marketing tool, or Interactive Electronic Technical Manual because of the design information security problem and the license cost. Therefore, various lightweight visualization formats and application systems have been suggested to overcome these problems. However, most of these lightweight formats are dependent on the companies or organizations which suggested them and cannot be shared with each other. In addition, product structure information is not represented along with the product geometric information. In this paper, we define a dataset called prod-X3D(Enhanced X3D Dataset for Web-based Visualization of 3D CAD Product Model) based on the international standard graphic format, X3D, which can represent the structure information as well as the geometry information of a product, and propose a translation method from 3D CAD data to an prod-X3D.

Study on tension-tension fatigue strength properties of underwater welded joints of SM41A-2 Plate-to-Plate (수중용접한 국산 SM41A-2강판의 편진반복 인장하중하의 피로강도특성에 관한 연구)

  • 오세규;박주성;한상덕
    • Journal of Advanced Marine Engineering and Technology
    • /
    • v.11 no.2
    • /
    • pp.71-81
    • /
    • 1987
  • Nowadays, the high development of industrial technique demands the optimal design of marine structures to be welded under the water, because the underwater welding of the ship hull and marine structures can decrease manpower and cost of production. However there is not available at present any report on fatigue behavior about underwater welded joints. In this paper under tention- tension repeated fatigue stress with frequency of 10 cycles per second by local controlled system, the fatigue strength properties of underwater welded joints of SM41A-2 Plate-to-Plate of 10 mm thickness were experimentally examined. The results obtained were as follows : 1) The fatigue strength of underwater welded joints of SM41A-2 was peaked at the heat input of about 1, 400 joule/mm(180 A, 36 V), while, at the heat input of more than about 1, 100 joule/mm (160 A, 33 V) that of the underwater welds at the higher than cycle of life rather than the lower cycle was higher than that of the base metal but lower than that of the atmosphere welds on account of both cooling and notch effects. 2) The fatigue limit of underwater welds increased with an increase of heat input resulting in a peak of that at the heat input of about 1, 400 joule/mm and then decreased gradually. 3) The fatigue strength at N cycles was peaked between the heat input of about 1, 400 and 1, 700 joule/mm where the strain was rapidly increased. 4) It was confirmed that the optimal zone of heat input condition for obtaining the underwater welds fatigue strength higher than that of the base metal exists, and if out of this zone, the fatigue strength of the underwater welds was lower than that of the base metal because of lack weld penetration, inclusion of slag, voids, etc. 5) By the fatigue test, the underwater welds fractured brittly without visual deformation, so the strain was remarkably less than of the atmosphere welds. 6) The fatigue life factor was peaked at the heat input of about 1, 600 joule/mm (200 A, 36 V) at which the mean strain is a little higher than that of the base metal but quite lower than those of the atmosphere welds, resulting in good underwater welds because both fatigue strength and ductility of the underwater welds are higher than those of the base metal at such heat input.

  • PDF

The Mechanical Modeling and design of saw frame in band sawing machine (띠톱기계 톱대의 역학적 모델링 및 설계)

  • LUO, luPing;DING, zelin;DING, shengxia;JIANG, Ping;FAN, li;XIAO, leihua;PAN, bosong;An, Boyoung;No, Joonkkyu;Li, Wenqi;Han, Changsoo
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.20 no.12
    • /
    • pp.390-397
    • /
    • 2019
  • A mechanical model of band sawing saw frame was established according to an analysis of a commonly used saw-frame structure diagram to overcome the problems of low service life, substandard cutting precision and efficiency, and high manufacturing cost caused by the unreasonable design of saw frame. Taking a particular type of sawing machine as an example, stress cycle analysis of the saw blade was carried out according to the mechanical model of the saw frame, and the fatigue analysis model of the most dangerous cross-section point that was most prone to fatigue failure of the saw blade was then established. The fatigue analysis result was used as the basis for the improved design of the saw frame, and the improved detailed saw-frame design parameters were obtained. The results suggested that the saw frame system is much more compact and the saw blade force met the fatigue strength requirements through the improved design. In addition, the service life of the saw blade and the cutting precision were increased. The established mechanical model of the saw frame in this paper is used widely and has high practical application values.

Evaluation of Hydrogen Properties on Mg2NiHx-Graphene Composites by Mechanical Alloying (기계적 합금화법으로 제조한 Mg2NiHx-Graphene 복합재료의 수소화 특성 평가)

  • Lee, Young-Sang;Lee, Soo-Sun;Lee, Byung-Ha;Jung, Seok;Hong, Tae-Whan
    • Transactions of the Korean hydrogen and new energy society
    • /
    • v.25 no.1
    • /
    • pp.19-27
    • /
    • 2014
  • Mg hydride has a high hydrogen capacity (7.6%), at high temperature, and is a lightweight and low cost material, thus it a promising hydrogen storage material. However, its high operation temperature and very slow reaction kinetics are obstacles to practical application. In order to overcome these disadvantages of Mg hydride, graphene powder was added to it. The addition of graphene has been shown to reduce the operating temperature of dehydrogenation. Moreover, in this report the environmental aspects of $MgH_x$-Graphene composites are investigated by means of the environmental life cycle assessment (LCA) method. $MgH_x$-Graphene mixture was prepared by hydrogen induced mechanical alloy (HIMA). The synthesized powder was characterized by XRD(X-ray Diffraction). The hydrogenation behaviors were evaluated by using a Sievert's type automatic PCT apparatus. Such evaluation of Materials also conducted in the LCA. From the result of P-C-T(Pressure-Composition-Temperature) curves, the $MgH_x$-3wt.% graphene composite was evaluated as having a 5.86wt.% maximum hydrogen storage capacity, at 523K. From absorption kinetic testing, the $MgH_x$-7wt.% graphene composite was evaluated as having a maximum 6.94wt.%/ms hydrogen absorption rate, at 573K. Environment evaluation results for the $MgH_x$-graphene composites and other materials indicated environmental impact from the electric power used and from the materials themselves.