• Proceedings of the Safety Management and Science Conference
• /
• 2004.11a
• /
• pp.131-141
• /
• 2004

This study deals with the procedure of safety improvement, productivity increase, and tact-time reduction through setting up the system about preventive maintenance. Actually, it is hard to establish and carry out preventive maintenance, even though we recognize the importance of the system concerning time, cost, labor, and so forth. In this study in the viewpoint of cost we are for achieving maximum efficiency by change and reduction of planning process adapted to the special work group. At first we briefly will mention the kind, the necessity, and the concept of preventive maintenance, and then divide the equipment used in the assembly line into the two whether it is necessary or not by way of estimating the breakdown loss, comparing with general establishment of preventive maintenance and modifying it to the case. At the second step we will establish the operation system of plan management related to production and quality in the special case. Check period and category will be set by dividing the assembly equipment into LCL and Focus in the third step. The forth step will contain the operation procedure in detail. And then we must make check and repair record periodically. Finally, on the basis of the record the selection of checking of significance will be conducted. This results in safety improvement, tact time reduction, and productivity improvement.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.66 no.12
• /
• pp.1712-1720
• /
• 2017

In South Korea, minimum reserve rate, which is to satisfy reliability standard, has been determined by simulation result using WASP. But, it is still controversial whether the level of minimum reserve rate is adequate. Thus, in this study, various analyses of minimum reserve rate are being conducted. WASP uses the probabilistic simulation technique to evaluate whether reliability standard is satisfied. In this process, forced outage rate and maintenance periods of each generator play important roles. Especially, the long-term plan can be varied depending on how maintenance periods deal with. In order to model maintenance periods in the probabilistic simulation technique, WASP uses derating method. However, broad analyses have to be conducted because there are various ways including derating method to model maintenance periods which result in different results. Therefore, in this paper, 3 different maintenance outage rate modeling methods are applied to arbitrarily modeled system based on the basic plan for long-term electricity supply and demand of South Korea. Results show impact of each modeling method on minimum reserve rate.

• Industrial Engineering and Management Systems
• /
• v.7 no.1
• /
• pp.51-56
• /
• 2008

With growing demand for zero defects, predicting reliability of software systems is gaining importance. Software reliability models are used to estimate the reliability or the number of latent defects in a software product. Most reliability models to estimate the reliability of software in the literature are based on the development lifecycle stages. However, in the maintenance phase, the software needs to be corrected for errors and to be enhanced for the requests from users. These decrease the reliability of software. Software Reliability Growth Models (SRGMs) have been applied successfully to model software reliability in development phase. The software reliability in maintenance phase exhibits many types of systematic or irregular behaviors. These may include cyclic behavior as well as long-term evolutionary trends. The cyclic behavior may involve multiple periodicities and may be asymmetric in nature. In this paper, SGRM has been adapted to develop a reliability prediction model for the software in maintenance phase. The model is established using maintenance data from a commercial shop floor control system. The model is accepted to be used for resource planning and assuring the quality of the maintenance work to the user.

• International conference on construction engineering and project management
• /
• 2009.05a
• /
• pp.856-863
• /
• 2009

The problem of urban decay in Hong Kong has drawn much attention of both practitioners and academics. Poorly managed buildings not just give a negative image to the Pearl of the Orient in the region, but also pose potential risk hazards to the health and safety of the general public. While it is necessary to devise a comprehensive plan on redevelopment and urban planning, preserving the existing buildings to maintain their conditions for habitation can be a short-term option to safeguard quality standard. With the increasing number of ageing buildings in Hong Kong, a lot of research efforts have been devoted to managing repair and maintenance projects properly (for example those initiated and funded by the Construction Industry Institute, Hong Kong; and the current study financially supported by The Hong Kong Polytechnic University). Given the short duration and more diversified nature of work, building repair and maintenance works are found to be more difficult to monitor and regulate when compared with new works. This paper aims to provide a comprehensive analysis on the problems of running building maintenance projects. An extensive review of contemporary literature was firstly conducted, which forms a solid basis for developing an empirical study on the problems and difficulties of running building maintenance projects from the viewpoints of industrial practitioners with a view to formulating effective strategies for managing maintenance projects successfully.

• The Journal of the Korea Contents Association
• /
• v.14 no.3
• /
• pp.438-450
• /
• 2014

The statistical analyzing of environmental-friendly planning elements is getting important because it is getting concerned with the change of residential types and environmental friendly housing. However, in terms of the high-rise residential complex, paper about green building rating system and research about residential satisfaction to residents are lack. Therefore, this paper is analyzing of impotentness and satisfaction about housing subdivision, inside of building, facility, and maintenance. In addition, residential satisfaction(satisfaction, loyalty, preference) and impact relationship of environmental-friendly planning elements are analyzed by PLS structural equation. To sum up, first, improving of green building rating system in housing subdivision is impacted on loyalty if satisfaction was fulfilled. Second, increasing of environmental-friendly planning elements in inside of building is impacted on loyalty if both satisfaction and preference were fulfilled. Third, providing of green building rating system in facility and maintenance is analyzed as preference, but satisfaction hypotheses is not valued.

• Proceedings of the Safety Management and Science Conference
• /
• 2010.04a
• /
• pp.219-230
• /
• 2010

Remarkably improvements have occurred recently in the maintenance management of physical assets and productive systems, so that less wastages of energy and resources occur. The technology of maintenance is about finding and applying cost-effective ways of avoiding or overcoming performance deterioration. Maintenance is thus a vital support function in business, especially as increasingly large investments are being required in physical assets. TPM(Total Productive Maintenance) focuses on optimizing planning scheduling. Availability, performance and quality rate are other factors that affect productivity. Especially there are some losses that affect the overall equipment effectiveness(OEE). These losses lead to low values of OEE, which provides an indication of how effective the production precess is. This study explores the ways in which Korean small and medium manufacturing industries can improve OEE.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.56 no.11
• /
• pp.1892-1902
• /
• 2007

This paper presents a new generating unit maintenance scheduling algorithm considering regional reserve margin and transfer capability. Existing researches focused on reliability of the overall power systems have some problems that adequate reliability criteria cannot be guaranteed in supply shortage regions. Therefore specific constraints which can treat regional reserve ratio have to be added to conventional approaches. The objective function considered in this paper is the variance (second-order momentum) of operating reserve margin to levelize reliability during a planning horizon. This paper focuses on significances of considering regional reliability criteria and an advanced hybrid optimization method based on PSO algorithm. The proposed method has been applied to IEEE reliability test system(1996) with 32-generators and a real-world large scale power system with 291 generators. The results are compared with those of the classical central maintenance scheduling approaches and conventional PSO algorithm to verify the effectiveness of the algorithm proposed in this paper.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.18 no.36
• /
• pp.265-273
• /
• 1995

This paper is to analyze and provide some managerial requirements for the successful implementation of total productive maintenance system. It tries to identify determining factors for success and reasons for the failures of TPM, based on the research of a survey and an empirical study through the years in Korea. The findings are such that many companies have not been engaged in planning and control the maintenance cost and their maintenance activities are not organized systematically. However, many indicators show that the number of finns which try to introduce and implement TPM is getting increased. The successful implementation of TPM depends largely on how top management perceives TPM and how the firm responds In the changes of organization and of the role of workers to adapt this new concept of work. It is required that TPM is perceived as a means to achieve the firm's business objectives. It is recommended that each company constructs and develops its own model and procedures to drive the effort for TPM implementation.

• Journal of Korean Institute of Industrial Engineers
• /
• v.22 no.4
• /
• pp.619-631
• /
• 1996

This paper describes an approach for the incorporation of maintenance times into a hierarchical scheduling for a failure prone flexible manufacturing system. The maintenance should not be performed too often because of the resulting reduction of capacity. Most manufacturing systems are large and complex. It is natural to divide the control into a hierarchy consisting of a number of different levels. Each level is characterized by the length of the planning horizon and the kind of data required for the decision making process. The goal of the analysis reported here is to calculate the production requirements while the machines fail and are repaired at random times. The machine failure and preventive maintenance are considered simultaneously.

• Journal of Korean Society of Rural Planning
• /
• v.17 no.2
• /
• pp.23-32
• /
• 2011

The purpose of this study is to produce basic planning criteria required in ecological restoration and improvement works of streams in rural area through the application of stream assessment methods (water quality, soil environment, and ecological function assessment) at 6 study sites of Han River basin. The investigation results were as followings; 1) There were the evaluation items like a manure use, salt degree, river peripheral tree, which did not fitted to apply to domestic streams, in the SVAP (Stream Visual Assessment Protocol) and NRCS Riparian Assessment that were evaluation models developed in USDA. The area inhabitants with a little knowledge and education personally seems to utilize the evaluation methods through improvement partly with an aspect that evaluation is slightly easy. 2) From the stream assessment results, the construction of diverse pools, large woody debris and isolated backwater pool are needed to improve a few of problems observed at the mostly study sites. The result of NRCS Riparian Assessment showed that the improvement of stream bank vegetative communities is needed by planting tree with deep-binding root masses, and managing of noxious weeds and exotic undesirable plants. 3) Summing up, the assessment results showed that the assessment scores were higher at upstream than downstream, the stream with totally maintenance than that with partly maintenance, the stream with slope bank than that with vertical bank, and the stream with a flood plain than that without a flood plain. So, the direction of stream maintenance projects must be set by consideration of those results.