• Title/Summary/Keyword: Life-cycle Cost Evaluation

Search Result 202, Processing Time 0.023 seconds

Classification Scheme of Usability Problems : Literature Review and New Conceptual Framework (사용성 문제의 분류 체계 : 문헌분석 및 새로운 개념적 프레임워크)

  • Ham, Dong-Han
    • Journal of Information Technology Services
    • /
    • v.7 no.4
    • /
    • pp.179-198
    • /
    • 2008
  • It is widely known that usability is a critical quality attribute of IT systems. Many studies have developed various methods for finding out usability problems. Usability professionals have emphasized that usability should be integrated into the development life cycle in order to maximize the usability of systems with minimal cost. To achieve this, it is essential to classify usability problems systematically and connect them into the activities of designing user interfaces and tasks. However, there is a lack of framework or method for these two problems and thus remains a challengeable research issue. As a beginning study, this paper proposes a conceptual framework for addressing the two issues. We firstly summarize usability-related studies so far, including usability factors and evaluation methods. Secondly, we review seven approaches to identifying and classifying usability problems. Based on this review and opinions of usability engineers in real industry as well as the review results, this paper proposes a framework comprising three viewpoints, from which more sound classification scheme of usability problems can be inductively developed.

Convergence Security Provider Self-Conformity System (융합보안 공급자 자기 적합성 제도)

  • Baik, Namkyun
    • Journal of Korea Society of Digital Industry and Information Management
    • /
    • v.15 no.2
    • /
    • pp.53-61
    • /
    • 2019
  • In this paper, we propose 'a self - conformance system of convergence security provider' to provide basic data for security and reliability of convergence industrial technology, system and service. It is difficult to evaluate convergence security systems, limited to information and communication service providers, unable to check convergence security items, burden of submission documents, difficulty in measuring convergence security service level and we will summarize product and service-based requirements that can be integrated and systematically measure the level of convergence security and define renewed life cycle-based convergence security information and content security and assurance requirements. On the basis of this, each convergence security company declares conformity with the standard itself without the certification of the certification body, and introduces the provider conformity certification system which can manufacture and sell. This will enable the company to strengthen its competitiveness through timely launch and implementation of products and services and cost reduction.

Factors Influencing Cost Overruns in Construction Projects of International Contractors in Vietnam

  • VU, Thong Quoc;PHAM, Cuong Phu;NGUYEN, Thu Anh;NGUYEN, Phong Thanh;PHAN, Phuong Thanh;NGUYEN, Quyen Le Hoang Thuy To
    • The Journal of Asian Finance, Economics and Business
    • /
    • v.7 no.9
    • /
    • pp.389-400
    • /
    • 2020
  • A construction project is a designed product made up of labors, materials, and installations in the project positioned on the ground and may include the underground and ground section, and the section in water or on the water surface. It is a civil, industrial, transport, agricultural and rural development, infrastructure, or some other. A key phase in the life cycle of these construction projects is the implementation when building products are made directly with workers, equipment, materials, and managers. If there is a lack of management experience, information, and problem-solving solutions to tackle the risks faced by contractors, especially foreign ones, will fail in controlling the project's cost. This study was conducted with investigations, discussions, and evaluation of the factors that lead to cost overruns in the construction projects of international contractors in Vietnam. The principal component analysis (PCA) showed that those factors that influence cost overruns these construction projects fall into five general groups, including factors related to (i) the owners, (ii) the foreign contractors, (iii) the subcontractors and suppliers, (iv) state management, and (v) the project itself. Besides, the study proposes solutions to limit cost overruns in construction projects and improve the profitability of international contractors in Vietnam.

Reliability Optimization of Urban Transit Brake System For Efficient Maintenance (효율적 유지보수를 위한 도시철도 전동차 브레이크의 시스템 신뢰도 최적화)

  • Bae, Chul-Ho;Kim, Hyun-Jun;Lee, Jung-Hwan;Kim, Se-Hoon;Lee, Ho-Yong;Suh, Myung-Won
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.31 no.1 s.256
    • /
    • pp.26-35
    • /
    • 2007
  • The vehicle of urban transit is a complex system that consists of various electric, electronic, and mechanical equipments, and the maintenance cost of this complex and large-scale system generally occupies sixty percent of the LCC (Life Cycle Cost). For reasonable establishing of maintenance strategies, safety security and cost limitation must be considered at the same time. The concept of system reliability has been introduced and optimized as the key of reasonable maintenance strategies. For optimization, three preceding studies were accomplished; standardizing a maintenance classification, constructing RBD (Reliability Block Diagram) of VVVF (Variable Voltage Variable Frequency) urban transit, and developing a web based reliability evaluation system. Historical maintenance data in terms of reliability index can be derived from the web based reliability evaluation system. In this paper, we propose applying inverse problem analysis method and hybrid neuro-genetic algorithm to system reliability optimization for using historical maintenance data in database of web based system. Feed-forward multi-layer neural networks trained by back propagation are used to find out the relationship between several component reliability (input) and system reliability (output) of structural system. The inverse problem can be formulated by using neural network. One of the neural network training algorithms, the back propagation algorithm, can attain stable and quick convergence during training process. Genetic algorithm is used to find the minimum square error.

Evaluation of Handover Requirements of Construction Information for Efficient Facility Management (효율적인 자산관리를 위한 건설정보 이양요건 평가)

  • Lee, Ikhaeng;Jung, Youngsoo
    • Korean Journal of Construction Engineering and Management
    • /
    • v.19 no.4
    • /
    • pp.12-20
    • /
    • 2018
  • As facilities have become larger, more complex, and advanced, the importance of the facility management in the operation phase of the building is increasing. As a result, the scope of the facility management function is expanding, and the requirements of information are ever-increasing. However, inefficient exchange of information occurs due to duplicated tasks and lack of collaboration among the construction life cycle phases, resulting in cost loss. These low interoperability issues can be complemented by construction information management from a life cycle perspective. Efficient construction information management at each life-cycle stage is derived from the owner's will and is materialized through the construction information handover requirements by the owner. The purpose of this study is to develop an evaluation method of construction information handover requirements for facility management. In order to develop the method, facility management types and business functions are also classified and defined in this paper. Using the methodology proposed by this study, a case-study of evaluating the 'takeover items' submitted by contractors was performed for the purpose of research validation. The results of the case-study found that the most effective areas are in the order of 'legal informations', 'drawings', 'guides', etc. This study can be used as a reference data for deriving handover requirements for construction information at the early stage of the project.

Development of LCC-LCA Integrated Analysis Model for Efficiency (경제성 평가를 위한 LCC-LCA 종합분석 모델 개발 및 사례적용)

  • Ahn, Hye-Ryeon;Lim, Jin Ho;Huh, Young-Ki
    • Journal of the Korea Institute of Building Construction
    • /
    • v.13 no.6
    • /
    • pp.585-593
    • /
    • 2013
  • For a successful construction project, systematic and objective decision-making is a prerequisite from the planning and designing stages. However, previous LCC analysis methods have focused only on simple cost savings and the accompanying economic efficacy while missing the environmental aspects of a structure. Although recently, a new approach of integrated $CO_2$ analysis has been introduced, which is more advanced than the existing simple LCC methods, it is difficult to collect all of the data necessary for each evaluation item since the product-specific cost is not presented under the LCC. In this research, cost evaluation items were selected by relatively high weights and items with heavy influence over a decision-making process in order to suggest an LCC-LCA integrated analysis model that is useful in comprehensively assessing the economic cost and environmental cost throughout the whole life cycle of a structure. The developed LCC-LCA integrated analysis model was applied to actual practices and compared with previous methods to test the model's effectiveness.

Calculation Model for Function & Cost Score based on Normalization Method in Design VE (정규화 기법 기반의 설계VE 기능 및 비용 점수 산출 모델)

  • Lee, Jongsik
    • Korean Journal of Construction Engineering and Management
    • /
    • v.16 no.4
    • /
    • pp.98-106
    • /
    • 2015
  • VE aims at reduction in a budget, improvement of function, structural safety and quality security for public construction projects. However, there is possibility for the structural safety and quality security review to be insufficient because related regulations are mostly composed of analysis on economic efficiency of design. In addition, due to the misconception about VE as a cost saving methodology, an alternative is being presented which still focuses mainly on cost saving, but with no objective evaluation of function related to cost. In order to improve this, the government adopted the reduction of life cycle cost and proposal of value improvement, and let people specify the cost and function of the original plan versus the alternative plan, and the value changes between them. However, it is written mainly into practical convenience rather than theoretical basis since a specific way is not suggested. The current method sets a different starting point by applying the attributional difference of function and cost. Furthermore, an evaluation standard for correlating is an important element in rational decision making for assessing and choosing an alternative. This paper analyzes the process and method of function & cost scoring when performing VE and suggests a mathematical normalization model in order to support rational decision making when selecting an optimum plan.

A implementation and evaluation of Rule-Based Reverse-Engineering Tool (규칙기반 역공학 도구의 구현 및 평가)

  • Bae Jin Young
    • Journal of the Korea Society of Computer and Information
    • /
    • v.9 no.3
    • /
    • pp.135-141
    • /
    • 2004
  • With the diversified and enlarged softwares, the issue of software maintenance became more complex and difficult and consequently, the cost of software maintenance took up the highest portion in the software life cycle. We design Reverse Engineering Tool for software restructuring environment to object-oriented system. We design Rule - Based Reverse - Engineering using Class Information. We allow the maintainer to use interactive query by using Prolog language. We use similarity formula, which is based on relationship between variables and functions, in class extraction and restructuring method in order to extract most appropriate class. The visibility of the extracted class can be identified automatically. Also, we allow the maintainer to use query by using logical language. So We can help the practical maintenance. Therefore, The purpose of this paper is to suggest reverse engineering tool and evaluation reverse engineering tool.

  • PDF

A Study on the Improvement Method of DT&E for Company Organized Weapon Systems Research and Development (무기체계 업체주관 연구개발 사업의 개발시험평가 개선방안 고찰)

  • Kim, Sungkyung;Kim, Chandong;HUR, Jangwook
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.18 no.6
    • /
    • pp.721-727
    • /
    • 2015
  • The improvement of the reliability of weapon systems and the reduction of the total life-cycle cost based on the improving of the DT&E system for Company Organized weapon systems research and development are urgently required. The major advanced countries operate test and evaluation centers for military (U.S.), manage a large scale organization of IPT personnel (England) or conduct management of DT&E through a third party organization (France). Based on a survey of experts, an improvement of the DT&E policy in terms of reliability and objectiveness is needed, and management through a third party national defense agency and civilian agency such as the Surion development case is required. In addition, although it appears that efficiency improves when management of DT&E is performed by national defence agencies rather than civilian agencies, it is necessary to proceed by selecting a civilian agency based on competition in the case that it is difficult to select a national defence agency.

Development and Evaluation of e-EBPP(Evidence-Based Practice Protocol) System for Evidence-Based Dementia Nursing Practice (근거중심 치매 간호실무를 위한 e-EBPP 시스템 개발 및 평가)

  • Park, Myonghwa
    • Korean Journal of Adult Nursing
    • /
    • v.17 no.3
    • /
    • pp.411-424
    • /
    • 2005
  • Purpose: The purpose of this study was to develop and evaluate e-EBPP(Evidence-based Practice Protocol) system for nursing care for patients with dementia to facilitate the best evidence-based decision in their dementia care settings. Method: The system was developed based on system development life cycle and software prototyping using the following 5 processes: Analysis, Planning, Developing, Program Operation, and Final Evaluation. Result: The system consisted of modules for evidence-based nursing and protocol, guide for developing protocol, tool for saving, revising, and deleting the protocol, interface tool among users, and tool for evaluating users' satisfaction of the system. On the main page, there were 7 menu bars that consisted of Introduction of site, EBN info, Dementia info, Evidence Based Practice Protocol, Protocol Bank, Community, and Site Link. In the operation of the system, HTML, JavaScript, and Flash were utilized and the content consisted of text content, interactive content, animation, and quiz. Conclusion: This system can support nurses' best and cost-effective clinical decision using sharable standardized protocols consisting of the best evidence in dementia care. In addition, it can be utilized as an e-learning program for nurses and nursing students to learn use of evidence based information.

  • PDF