• Journal of Korean Society for Quality Management
• /
• v.18 no.2
• /
• pp.9-17
• /
• 1990

This paper deals with a FOQ( ; fixed-order quantity) model for spare-part inventory control. In a spare-part inventory problem, stock depletion arises not from external market demand but from internal demand resulting from failures of parts in use. The problem differs from the classical inventory problem in that the demand for a failed part never arises more during stockout period, since the unit remains inoperative when stockout occurs until the failed part is replaced by new one. In the problem under consideration, n identical units are operating simultaneously and failed one is replaced immediately by new one if on-hand spares remain. In order to replenish spares, an order with quantity Q is placed whenever the number of on-hand spares falls to levels. The average annual cost of operating the spare-part inventory system is derived under the assumption that both lifetime of a part and replenishment lead-time distributions are exponential.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 1996.10a
• /
• pp.307-309
• /
• 1996

This paper analyses a deterministic scheduling problem concerned with manufacturing two types of components at a pre-assembly stage which consists of two independent feeding machines each producing its own type of component. Each type represents a unique component which may have variations in its size or quality. Therefore, the completion time of each component depends on both its type and quality (size) variations. Such manufactured components are subsequently assembled into various component dependent products. The problem has the objective measure of minimizing the total weighted completion time of a finite number of jobs(products) where the completion time of each job is measured by the latest completion time of its two components at the pre-assembly stage. The problem is shown to be NP-complete in the strong sense. A WSPT rule coupled with a machine-aggregation idea is developed for good heuristics which show the error bound of 2.

• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 1996.06c
• /
• pp.478-487
• /
• 1996

A " plucking rolls device" was developed in this study to improve the quality of harvested tea leaves. In this report, the outline of the system and the results of performance experiments in our laboratory are discussed. Tow kinds of performance experiments were carried out. The first experiment checked harvesting accuracy by using a plucking unit that was developed for harvesting machine installation. The second experiment was a harvesting experiment which utilized a fron bar in order to prevent cutting of the tea buds which had been a problem in precious experiments . As a results of the first experiments , it was confirmed that selective harvesting obtained high quality tea leaves. but a cutting problem that, when the harvesting seed was faster than the working speed, which was non-selective harvesting , was also seen. In the second experiment, the cutting rate decreased to a maximum of 50% level, when tea buds most bent ahead by the front bar. The effect was seen that cutt ng problem was alleviated from this.

• Knowledge Management Research
• /
• v.6 no.2
• /
• pp.149-168
• /
• 2005

Owing to the limits of IT System-driven knowledge management(KM) for innovation processes, alternative KM methods has been suggested such as: (1) the knowledge network of experts or (2) communities-of-practice. This study analyzes two cases in terms of on-line expert knowledge networks for problem-solving, with the dimensions of analysis based on a theoretical framework. By analyzing the cases of S company's expert network and Naver's Ji-sik-iN, we found that system quality(e.g., ease of use, accessibility, and searching function), information/knowledge quality(e.g., usefulness, accuracy, and timeliness), knowledge-sharing culture, social capital and relevant reward systems are important for stimulating a Q&A-based problem-solving knowledge network. Implications of the findings and future research directions are discussed.

• Proceedings of the Korea Society for Simulation Conference
• /
• 2003.11a
• /
• pp.139-144
• /
• 2003

Mobile Node has to maintain communication as they move form place to place, so it doesn't guarantee Quality of Service(QoS). Fast Handoff is important to provide multimedia and real-time applications services in mobile, and it is closely related to handoff delay. Therefore, handoff delay problem is actively studied to quarantee QoS as a main issue in mobile IP research area. Next generation Mobile IPv6 resolve this problem somewhat, triangle problem for first packet and handoff delay still remain. In this paper, we suggest SNMP Information-based routing that adds keyword management method to Information-based routing in active network in order to resolve such a problem, and then suggest QoS controlled handoff based on SNMP Information-Based routing. After modeling of suggested method and existing handoff method, simulations are carried out with NS-2 for performance evaluation. The results of simulations show the some improvement on handoff delay, and therefore on QoS improvement.

• International Journal of Quality Innovation
• /
• v.4 no.1
• /
• pp.131-147
• /
• 2003

This paper considers that a public department under specialized TQM manpower constraints have to implement multiple total quality management (TQM) policies to promote its service performance (fundamental goal) by adopting a centralized sequential advancement strategy (CSAS). Under CSAS, the decision-makers (DMs) start off by focusing specialized TQM manpower on a single policy, then transfer the specialized TQM manpower to the next policy when the first policy reaches the predetermined implementation time limit (in terms of education and training). Suppose that each TQM policy has a different desirous education and training goal. When the desirous goals for all TQM policies are achieved, we say that the fundamental goal will be satisfied. Within the limitation of total implementation period of time for all policies, assume the desirous goals for all TQM policies cannot be achieved completely. Under this premise, the optimal implementation sequence for all TQM policies must be calculated to maximize the weighted achievement of the desirous goal. We call this optimization problem a TQM case of "centralized sequential decision-making problem (CSDMP)". The achievement of the desirous goal for each TQM policy is usually affected by the experience in prior implemented policies, which makes solving CSDMP quite difficult. As a result, this paper introduces the concepts of sequential effectiveness and path effectiveness. The structural properties are then studied to propose theoretical methods for solving CSDMP. Finally, a numerical example is proposed to demonstrate CSDMP′s usability.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2020.11a
• /
• pp.135-136
• /
• 2020

Recently, there is a problem that is most important in constructing buildings and building materials. It is a harmful substance generated in buildings. These harmful substances are CO₂, radon and formaldehyde, volatile organic compounds generated from building materials. These are bad for the human body, may have a negative effect and cause large illnesses such as cancer. Recently built apartments have a high density, so there is a problem that harmful substances do not escape well. As a result, people's interest in indoor air quality is growing and in order to solve this problem and various researches are being conducted on the materials used for concrete pouring to find out how much the materials used adsorb harmful substances. this study uses carbon black as a material that can adsorb these harmful substances. The purpose of this study is to measure the bending strength, compressive strength, and to determine whether the paste containing carbon black can improve indoor air quality.

• The Journal of the Korea Contents Association
• /
• v.9 no.1
• /
• pp.1-14
• /
• 2009

A currently domestic governmental R&D business is early to 100. And this is each managed individually in 15 professional organizations of research and management by characteristics of a business. For this Reason, A redundant investment issue regarding national R&D occurs, and an issue regarding efficiency of R&D investment by insufficiency of systematic R&D research project and result management is continuously raised. Ministry of Education Science and Technology establishing National Science & Technology Information Service(NTIS) in order to solve these issues. NTIS is the national R&D Portal System which can support efficiency of research and development to result utilization in planning of national research and development. In this paper We consider integrated DB constructions and Information Linking of R&D Participants/Projects/Results information in a NTIS system for data quality Improvement. and then We analyze the cause of the data quality problem, and we propose the improvement plan for data quality elevation of NTIS system.

• Journal of Korean Academy of Nursing
• /
• v.39 no.2
• /
• pp.207-216
• /
• 2009

Purpose: The purposes of this study was to analyze the effects of a health education program using problem-based learning on health related knowledge, behavior, and quality of life in elderly people. Methods: The participants included 44 elders, of whom 23 took the health education program and 21 did not. All participants were over 60 yr of age and were selected from residents of nursing homes or participants in activities of social welfare facilities in Jeju Province. Elders in both groups completed pre- and post-tests. Elders in the education group participated in 5 weekly sessions, 100-120 min/session of problem-based learning on health education. Data were analyzed using SPSS WIN 12.0. Results: Scores for health knowledge, health behavior, and quality of life for the education group were significantly higher than those of the control group. Conclusion: A problem-based learning health education program can be recommended as a method to promote the health of the elders. Indirectly, the results seem to indicate that proper assessment and support should be provided simultaneously in the management of elders' health. Finally, future study is needed to examine whether problem-based learning is more helpful compared to traditional education.

• Journal of Families and Better Life
• /
• v.9 no.1 s.17
• /
• pp.241-257
• /
• 1991

The objectives of this study are : to measure the level of rent burden. to examine the independent influences of the variables related to rent burden. to measure the level of family economic problem perception. to examine the differences in the level of family economic problem perception due to rent burden, household characteristics, housing characteristics and rent incresing. For these purpose, a survey is conducted using questionaires. The data used in this study included 369 renters living in Seoul. Statistics uses for data analysis were Frequency Distribution. Percentile, men, Pearson's Correlation, Partial Correlation, One-way ANOVA, Breakdown and Multiple Regression Analysis. Major findings are as follows : The average score of rent burden was 35.87, Therefore rent burden of large cities, rental households is very heavy. Family income, housing facility quality, rent type, and rent incresing have independent influences on rent burden. The average of family economic problem perception is above the mid-point of the scale. The level of family economic problem perception differs due to rent burden, family income, family life cycle, family size, occupation of household head, education leval of household head and homemaker, rent type, housing type, housing size, housing facility quality and rent increases. If the level of rent burden is below 25, family economic problem perception is adequate.