• Journal of Korean Society for Quality Management
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• v.47 no.4
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• pp.739-754
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• 2019

Purpose: The purpose of this paper is to develop a reliability estimation procedure for the underground gas pipeline in the presence of corrosion defects. Methods: Corrosion is one of the major causes of the gas pipeline failure. Several failure forms caused by corrosion have been studied. Among them, small leak and burst are considered in this paper. The composite failure of the two is defined by limit state function, and it is expressed with pipe parameters. Given a modified corrosion dataset, in order to obtain reliability estimations, the method of first order and second moment is adopted because of its simplicity. The computation processes are conducted with MATLAB coding. Results: According to numerical results, the probability of composite failure is affected by both small leak and burst. In particular, when corrosion depth stays at low level, it is consistent with the probability of burst failure. On the contrary, it is more influenced by the small leak failure as corrosion depth is increasing. In such case, the probability of composite failure is fast approaching to the safety limit. Conclusion: By considering the composite failure, more practical predictions of remaining life can be obtained. The proposed method is useful for maintenance planning of the underground gas pipeline.

• Korean Journal of Adult Nursing
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• v.19 no.1
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• pp.132-143
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• 2007

Purpose: The purpose of this study was to identify effects of a self-management program on symptom and functional status, health perception, and quality of life(QOL) of patients with CHF. Methods: Patients with CHF as defined through clinical judgment using the Framingham criteria and EF<50% were enrolled in the study (experimental: 21, control: 20). The symptom focused self-management program consisted of coping behaviors for symptoms including dyspnea, chest discomfort/pain, dizziness, ankle edema, and basic self-management including medications, diets, activity, lifestyle changes. Experimental group received an educational booklet after survey, and periodic telephone follow-up by a trained nurse. Data were collected the 3rd day after admission and at 1 month, 3 months, and 6 months after discharge using questionnaires. Results: Significant differences were found in the presence of symptoms, health perception, and QOL between groups during follow-up. Although no significant difference was found in functional status, the experimental group reported better functional status than the control group. Conclusion: By facilitating self-management of CHF using tailored interventions including education programs and telephone monitoring, it is expected that patients will be able to monitor their symptoms routinely, adhere to therapeutic regimen, and have a better QOL.

• International Journal of Reliability and Applications
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• v.2 no.3
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• pp.161-187
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• 2001

Starting with the meaning of the word quality, diverse concepts connoted by the term are examined. Instead of a bathtub curve, the desirable shape of a failure rate covering the entire life of a good product, which might be called hockey-stick line, is introduced. From the hockey-stick line and the definition of reliability, two measurements are extracted. The terms reliability, failure rate, product life, and durability are explained. From the customer's standpoint, the concept of product quality is classified in five factors, according to related technology: performance, reliability, conformance to specifications, customer perception, and fundamentals advantage. The correlation of the five factors for a first-class product is discussed, Since the market share of a company is determined as the competition result of its product value, defined as product quality and price, the market share increase is derived mathematically from the increment of product value. The market share increase, $\Delta$S, can be calculated from the present market share, S, and the oriented relative value increment of new product, R, to the current product in the same company for the same market target: $\Delta$S : $\Delta$(1-S). R/(1+S.R). Finally, the importance of separating warranty cost from the profit equation for the durables is explained.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.9
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• pp.218-228
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• 2020

The material industry is an important infrastructure industry that uses process technology in order to produce parts applied to the final product and determine the quality of the finished product. However, the market environment, which has been recognized as a 3D industry, has deteriorated recently and lost competitiveness compared to other material industry countries. This study analyzed the characteristics of forging companies and The study found that three characteristics of the forging industry, facility-oriented, order-based, and field-centered, and internal failure cost and external failure costs were set as the range of quality cost. A total of eight quality tasks were selected by applying the quality cost management system and continuous quality improvement process developed for large-scale A forging company, and improvement activity proved its effectiveness reducing quality costs by 63.3% compared to the previous year. The research helps forging companies establish a quality management strategy by systematically managing and analyzing quality costs.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.6
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• pp.385-397
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• 2021

This study examined service failure and recovery of domestic ethnic food restaurants based on a model of the repercussions of service failure dealing with seriousness and control and the cause-and-effect relationships among the variables relevant to the quality of relationships -trust, satisfaction, and loyalty. This study provides valuable information for Korean restaurant managers regarding food service failure and response plans by collecting data from actual Japanese tourists visiting ethnic food restaurants. The results suggested that it is important to develop a strategy to present the distributional fairness to customers who recognize the seriousness of service failure to control the situation promptly. These results can be used to establish more systematic business plans, improving customer management and firm performance. The advantage of this research is that it is time for substantial research data on the booming domestic restaurant industry and service quality to overcome the current recession and grow and solidify the current restaurant market.

• Journal of the Korean Operations Research and Management Science Society
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• v.27 no.3
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• pp.115-133
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• 2002

In this paper, 15 South Korean telecommunications service failure cases were analyzed. Through the in-depth case study, 8 factors were found to be the major causes contributing to the telecommunications service failure. They were (1) ineffective marketing, (2) poor demand forecasting due to misjudgment of customer preference, (3) failure to satisfy technical specifications, (4) loss of cost advantage due to the price cut of competing services or new entry with lower price, (5) loss of utility advantage due to the increased utility of competing services or new entry with higher utility (6) decrease of market attractiveness due to change of customer preference, (7) impact of government policy, and (8) insufficient or low quality of contents. Additional analysis was done to derive managerial implications to the new telecommunications service development strategy. The findings from the paper will provide valuable Insight to the successful Implementation of new service development and service provisioning processes.

• International Journal of Heart Failure
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• v.6 no.3
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• pp.107-116
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• 2024

Frailty is highly prevalent among patients with heart failure (HF) and independently predicts adverse outcomes. However, optimal frailty definitions, assessments, and management in HF remain unclear. Frailty is common in HF, affecting up to 80% of patients depending on population characteristics. Even pre-frailty doubles mortality risk versus robust patients. Frailty worsens HF prognosis through systemic inflammation, neurohormonal changes, sarcopenia, and micronutrient deficiency. Simple screening tools like gait speed and grip strength predict outcomes but lack HF-specificity. Comprehensive geriatric assessment is ideal but not always feasible. Exercise, nutrition, poly-pharmacy management, and multidisciplinary care models can help stablize frailty components and improve patient-centred outcomes. Frailty frequently coexists with and exacerbates HF. Routine frailty screening should guide supportive interventions to optimize physical, cognitive, and psychosocial health. Further research on HF-specific frailty assessment tools and interventions is warranted to reduce this dual burden.

• Journal of Korean Society for Quality Management
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• v.26 no.2
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• pp.106-117
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• 1998

The following study has been undertaken to build QIP (Quality Improvement Process) of an inner-layer process in a PCB (Printed Circuit Board) manufacturing plant. The objective of the study is stabilization and optimization of the process through quality improvement. To do that, defective factors in process are gathered by the cause and effect analysis and classified by PFD (Process Flow Diagram), key factors are found out by PFMECA (Process Failure Mode and Effect Criticalty Analisis), DOE(Design of Experiments) is a, pp.ied to those key factors to optimize the process, SPC (Statistical Process Control) chart is used to maintain the optimal conditions of the process and to improve quality continuously, and a quality management system is developed to improve quality mind and quality system for the PCB jmanufacturing plant. Overall, QIP is established to improve quality for the PCB manufacturing plant in the study.

• Proceedings of KOSOMES biannual meeting
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• 2001.10a
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• pp.117-134
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• 2001

Quality costs seem to be one of the effective tools to assess quality management activities, but shipping industries have not controlled quality costs because of difficulty in cost itemization and cost data collection. This study has attempted to itemize shipping quality costs in detail and researches the composition of actual quality costs of sampled shipping companies in Korea. Result of research shows that stopping quality costs were composited by 24.3%, 3.8% and 71.8% of prevention costs, appraisal costs and failure costs, respectively and very high relationship between total qualify cost and other quality costs. This research also recommended practical methods for quality management by using indexes of quality costs.

• Journal of Multimedia Information System
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• v.7 no.1
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• pp.55-72
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• 2020

As the IT service environment grows, it is critical in terms of IT service quality to minimize the occurrence of failures due to changes in applications and to diagnose and recover in a short period of time how failure will affect the business. Thus, the Defense Acquisition Program Administration (DAPA) has been building and operating ITSMs to implement IT service management in a leading manner. Information Technology Service Management (ITSM) is divided into events, obstacles, changes, versions and setup management to ensure flexibility and stability in service delivery. It is also operated separately from service level, availability, capacity, financial and IT service continuity management to ensure service quality and cost efficiency. Based on ITSM military service history, this study looks at the impact of quality of service on value, satisfaction, and trust. The results of the analysis are highly valuable for future ITSM implementation and operation.