• Journal of Korean Society of Transportation
• /
• v.30 no.3
• /
• pp.71-82
• /
• 2012

This study analyzed factors affecting daily travel times at each stage of commuters' life cycle. In this study, travel times were dealt with in the context of trip chain. That is, the travel time was defined as the total amount of time commuters had spent to move for daily activities from leaving to coming back home. A commuter's life cycle was divided into 6 stages on a basis of both householder's age and family type: i.e., the unmarried youth period, the family forming period, the children education period, the children youth period, the children independence period, and the aged period. Variables such as commuting times, home-based trip cycle recurrences, and the number of stops differed for each stage of life cycle, the latter of which represents how many places a commuter dropped by during a trip cycle. Several factors were found to affect commuting times at each stage of life cycle as a result of applying a Cox proportional hazard model. The empirical study was conducted using 2010' household travel survey data collected from Gyeonggi-do.

• Proceedings of the KIEE Conference
• /
• 2011.07a
• /
• pp.2169-2170
• /
• 2011

This paper presents about the analysis on cost factor reduction using the life cycle cost model for motor block in the KTX-1. Until now, most life cycle cost of the system as a whole that has been studied. but in case of railway industry part, LCC studies are needed on the subsystem like a propulsion control system because subsystems are developed continuously localization. Therefore, In this paper presents cost breakdown structure for life cycle cost (LCC) estimation for localization development of propulsion control system (Motor Block) in high speed railway vehicle (KTX-1). Also to analysis LCC on motor block, it was analyzed physical breakdown structure (PBS) and preventive cost on propulsion control system in view of maintenance cost. Based on this, we describe life cycle cost on motor block of KTX-1.

• Journal of the Korean Society of Safety
• /
• v.17 no.2
• /
• pp.63-68
• /
• 2002

Life Cycle Cost analysis technique is introduced to evaluate cost-effectiveness of two paint systems of steel bridges. The systems are a conventional paint system and a galvanized paint system. The all costs during safe lift such as initial cost repainting costs, disposal costs are considered for the lift cycle cost analysis. The NIST model is used and BridgeLCC 1.0 developed by the NST is utilized as the lift cycle cost analysis tool. It is concluded that, in spite of expensive initial cost, the durable paint system may be cost-effective compared with conventional paint system.

• Journal of the Korean Home Economics Association
• /
• v.30 no.1
• /
• pp.199-217
• /
• 1992

The purpose of this study was to examine changes in the household investment planning according to the family life cycle, to improve the household investment planning process, and to develop research model. The results were as follows : Household investment planning varied with stages of the family life cycle because the stock of resources shifted and financial goals changed as the family life cycle stage changed. The main financial goals of family in each stage of the life cycle were the purchasing of house in the establishing stage, children's education and marriage in the extending stage, and the elderly's economic welfare in the diminishing stage. Also, in the Ⅰ & Ⅱ stage the most important investment goals were the purchasing of house, children's education in the Ⅲ stage, children's marriage in the Ⅳ stage, and the elderly's economic welfare in the Ⅴ stage. Therefore, the financial goals were recognized as the important goals underlain the investment-planning goals, and alternatives for the accomplishment of investment-planning goals were determined. The results of this study can contribute to establish the long-run investment planning process and improve the level of household's financial well-being.

• Proceedings of the KSR Conference
• /
• 2007.11a
• /
• pp.1132-1140
• /
• 2007

As it recently appears that Life Cycle Cost Analysis may be considered as new methodology for economic valuation of infrastructure many researches have been made to assess LCC(Life Cycle Cost) of each facility based on a reasonable methods. In general, LCC is composed of construction cost and expected maintenance repair cost. And especially, maintenance repair cost must be estimated to enhance the reliability through systematic and reasonable methods. However in Korea, because high speed railway steel bridges are recently constructed no direct statistical data are available for the account of the maintenance cost and then their maintenance characteristics are not linear yet. Therefore, the approach proposed in the paper utilizes a theoretical determination and degradation of the corrosion and fatigue of the bridges based on Rahgozar et al.(2006)'s model on fatigue notch factor considering into the corrosion to incorporate the corrosion effect into the fatigue strength reduction model. And then, the corresponding probability of failure is calculated in terms of the reliability index using S-N curve to formulate the fatigue limit state. Therefore, this paper proposes the minimum Life Cycle Cost through optimum maintenance plan analysis of high-speed railway steel bridges under construction. Finally, this paper reviews the proposed model in oder to confirm the applicability and feasibility by appling it to high speed railway steel bridges under construction

• The Transactions of the Korea Information Processing Society
• /
• v.6 no.5
• /
• pp.1189-1202
• /
• 1999

As compared with VOD data, NOD article data has the following characteristics: it is created at any time, has a short life cycle, is selected as not one article but several articles by a user, and has high access locality in time. Because of these intrinsic features, user access patterns of NOD article data are different from those of VOD. Thus, building NOD system using the existing techniques of VOD system leads to poor performance. In this paper, we analysis the log file of a currently running electronic newspaper, show that the popularity distribution of NOD articles is different from Zipf distribution of VOD data, and suggest a new popularity model of NOD article data MS-Zipf(Multi-Selection Zipf) distribution and its approximate solution. Also we present a life cycle model of NOD article data, which shows changes of popularity over time. Using this life cycle model, we develop LLBF (Largest Life-cycle Based Frequency) prefetching algorithm and analysis he performance by simulation. The developed LLBF algorithm supports the similar level in hit-ratio to the other prefetching algorithms such as LRU(Least Recently Used) etc, while decreasing the number of data replacement in article prefetching and reducing the overhead of the prefetching in system performance. Using the accurate user access patterns of NOD article data, we could analysis correctly the performance of NOD server system and develop the efficient policies in the implementation of NOD server system.

• Journal of Korean Library and Information Science Society
• /
• v.53 no.3
• /
• pp.25-46
• /
• 2022

In this study, the appraisal in record continuum theory is analyzed in conjunction with the appraisal in life cycle model. In order to understand the more fundamental implications of appraisal in electronic record environment, it is essential to analyze the appraisal inherent in record continuum theory. Record continuum theory can provide a theoretical basis for appraisal in electronic record environment in that it is a theoretical system in opposition of the appraisal based on life cycle model and dualistic records management system resulting from it. In particular, considering that the appraisal is a purposive act of seeking the meaning of records, the reinterpretation of the concept and meaning of records intended in record continuum theory enables us to derive the different appraisal logics than before. Therefore In this study, based on comparison with the appraisal based on life cycle model and the new record concept presented in record continuum, the appraisal in record continuum theory is analyzed focusing on three aspects.

• Proceedings of the Korean Institute Of Construction Engineering and Management
• /
• 2008.11a
• /
• pp.291-296
• /
• 2008

For the past two decades, 3D/4D CAD research has heel mainly focused on the design and construction phase of a facility life-cycle. However, there has been a general notion that the strength of 3D/4D CAD lends itself to other phases such as planning, operation and maintenance. In this research, a 3D/4D CAD model was generated in a commercial software platform. Then, the traditional 1:fe cycle facility management procedures are reviewed to, see any possible improvement opportunity with the 3D/4D CAD model as an example. A focus group interview, in conjuction with an extensive literature review, produced the list of area where 3D/4D CAD model could significantly benefit the traditional life cycle facility practices. Finally, a questionnaire-based survey was conducted with 155 respondents to statistically verify the feasibility of 3D/4D CAD for life cycle facility management.

• Journal of Information Technology Applications and Management
• /
• v.19 no.2
• /
• pp.135-147
• /
• 2012

Software architecture, as a blueprint for the system, should provide a robust foundation for design, implementation, and maintenance, for communication and documentation, and for reasoning about important system properties. Software architecture plays a central role during the whole software life-cycle. There are so diverse definitions of the software architecture, however, and there is no common agreement about what software architecture is. Examining 27 'published' definitions of software architecture, we synthesize an extensive model on the essential elements of software architecture, which consists of components, interaction among components, well-formed structure, reasons, and various perspectives. Further, we explore the possibility of unifying diverse software architecture definitions into a software architecture life-cycle model.

• International Journal of Naval Architecture and Ocean Engineering
• /
• v.11 no.2
• /
• pp.671-678
• /
• 2019

In this paper, the low cycle fatigue failure and ratcheting behavior, as well as their interaction of AH32 steel were experimentally investigated under uniaxial cyclic loading. The effects of mean stress, stress amplitude and stress ratio on the low cycle fatigue life and ratcheting strain were discussed. It was found that the ratcheting strain increased while the fatigue life decreased with the increase of mean stress and stress amplitude, and the increasing stress ratio would result in smaller ratcheting and larger fatigue life. Two kinds of failure modes, i.e. low cycle fatigue failure due to crack propagates and ratcheting failure due to large plastic strain will take place respectively. Based on the experimental results, considered the effect of ratcheting on fatigue life, a model with the maximum stress and ratcheting strain rate was proposed. Comparison with the experimental result showed that the new model provided a good prediction for AH32 steel.