• International Journal of Precision Engineering and Manufacturing
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• 제8권4호
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• pp.10-15
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• 2007

Taguchi methods have been used for a long time to improve the product quality and process performance of a manufacturing system, Few researchers have applied this methodology in laser beam cutting (LBC) of sheet metals and found the considerable improvement in cut qualities. In all experimental investigations of LBC so far, the objective was to optimize the single quality characteristic at a time. In this paper the simultaneous optimization of multiple quality characteristics such as Kerf width and material removal rate (MRR) during pulsed Nd:YAG LBC of thin sheet of magnetic material (high Silicon-steel) has been presented using Taguchi's quality loss function. The results show the considerable improvement in multiple S/N ratio as compared to initial cutting condition. Also, the comparison of results from single and multi-objective optimization have been presented and it was found that the loss in quality is always possible shifting from single quality to multiple quality optimization.

• 한국토양비료학회지
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• 제35권6호
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• pp.381-386
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• 2002

관행시비 (4회 분시)에 비해 완효성 비료 2회 분시가 수량이 12.5% 증수하였으나, 1회 분시는 $6{\pm}3%$ 감소하였다. 관행시비에 비해 완효성 비료 2회 분시가 총질소, 총 아미노산, 엽록소, 비타민 C 함량과 감칠맛 주성분인 theanine, glutamic acid, arginine 함량이 많았고, tannin 함량은 적은 편이였으나, 완효성 비료 1회 분시는 2회분시와는 반대의 경향을 나타냈다. 형상, 향, 맛 등 제다품질은 완효성 비료 2회분시가 1회분시나 관행 시비 4회 분시에 비해 우수하였다. 결론적으로 완효성 비료의 분시효과가 우수한 이유는 비료성분이 서서히 용출되어 나와 효과적으로 작물에 공급되는 한편 비료성분의 손실을 줄일수 있었기 때문으로 판단된다.

• 품질경영학회지
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• 제45권3호
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• pp.403-426
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• 2017

Purpose:?The purpose of this study is to analyze the causal relationship between top management 's leadership and construction quality management activities that affect construction management performance based on construction quality management. Methods:?As its method, the causal relationship between the leadership of top management and the key management factors of construction quality management activities affecting management performance is analyzed by using the structural equation model. The construction companies used in the analysis sample conducted surveys on companies that are conducting ISO, KOSHA, OHSAS, DQC, and so on. Results:?It was revealed that top management's leadership has a great influence on management performance and all management factors of construction quality management activities. However, safety management does not affect the management performance of construction quality management activities. And top management's leadership on management performance are explained by the mediating effect of cost, time, quality and communication among management factors of construction quality management activities. Conclusion:?In the previous study, the quality management activities and the ISO - based integrated total quality management system (TQM) applied in the manufacturing or service industries were presented as empirical results. However, this study presents the results of different studies by presenting empirical study results by selecting time, cost, quality, safety and communication as key management factors of quality management activities of construction companies through reviewing and analyzing previous studies in construction field.

• 경영과정보연구
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• 제18권
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• pp.201-222
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• 2006

As the competition between countries has become higher and the notion of software quality has been widely spread. it has been necessary to develop technologies that can ensure and produce high quality software. With the advent of information-oriented society. quality control has to transfer to the quality control activities focused on software system instead of those activities focused on hardware system. If so, how do we get to handle the quality control on the basis of the new approach. Also, as software applications have grown. so too has the importance of software quality. In order to manage software quality, the technology to specify and evaluate both the software product quality and development process quality objectively quantitatively is most important. To produce products of good quality, we need a more progressive quality control system according to the need of software development life cycle. In other words, we do software right the first time or build quality in the process. On the basis intermediate and final time or build quality in the process. On the basis of data achieved, we can evaluate the products according to the consequences of the data, What are the problems to contrive the software quality control system?, we con promote the quality of products. To achieved that goal, we con provide a suitable the technique and method of software quality control.

• 경영과정보연구
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• 제15권
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• pp.245-262
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• 2004

As the competition between countries has become higher and the notion of software quality has been widely spread. it has been necessary to develop technologies that can ensure and produce high quality software. With the advent of information-oriented society. quality control has to transfer to the quality control activities focused on software system instead of those activities focused on hardware system. If so, how do we get to handle the quality control on the basis of the new approach. Also, as software applications have grown, so too has the importance of software quality. In order to manage software quality, the technology to specify and evaluate both the software product quality and development process quality objectively quantitatively is most important. To produce products of good quality, we need a more progressive quality control system according to the need of software development life cycle. In other words, we do software right the first time or build quality in the process. On the basis intermediate and final time or build quality in the process. On the basis of data achieved, we can evaluate the products according to the consequences of the data, What are the problems to contrive the software quality control system?, we con promote the quality of products. To achieved that goal, we con provide a suitable the technique and method of software quality control.

• 품질경영학회지
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• 제18권1호
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• pp.21-28
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• 1990

In this paper, the capacity of system which provides the real time response call service to the customer is studied. The quality of call service depends on the response time of the service in the system. Therefore, the focus of this paper is to investigate the capacity of system under the restriction of response time. In this paper, the system is modeled by queueing network. The analytical method is applied to solve this queueing network. The solution of the model has product form solution. To get the reasonable capacities, nonlinear programming problem is formulated and is solved by GINO.

• Journal of Welding and Joining
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• 제12권2호
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• pp.97-107
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• 1994

Both in-process quality control and high reliability of the weld is one of the major concerns in applying friction welding to the economical and qualified mass-production. No reliable nondestructive monitoring method is available at present to determine the real-time evaluation of automatic production quality control for friction welding of special hydraulic valve spool of 16mm in diameter. This paper, so that, presents the experimental examinations and statistical quantitative analysis of the correlation between the initial cumulative counts of acoustic emission(AE) occurring during plastic deformation periods of the welding and the tensile strength and other properties of the welded joints of $\phi16$ valve spool as well as the various welding variables, as a new approach which attempts finally to develop real-time quality monitoring system for friction welding.

• 한국해양공학회지
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• 제13권1호통권31호
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• pp.88-93
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• 1999

This paper presents the experimental examinations and statistical quantitative analysis of the correlation between the cumulative counts of acoustic emission(AE) during plastic deformation periods of the welding and the tensile strength and other properties of the bar-to-bar welded joints of O.D. 16mm shaft(SM40C) as well as the various welding variables. And this is a new approach which attempts finally to develop real-time quality monitoring system for friction welding. The results lead to a practical possibility of real-time quality control more than 100% joint efficiency showing good weld with no micro structural defects.

• 한국학교ㆍ지역보건교육학회지
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• 제20권1호
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• pp.15-27
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• 2019

Objective: Patients with COPD have a lower overall quality of life than normal people. If patients with COPD do not regularly perform physical activities, their exercise capacity is reduced. It could lead to muscle loss, and negatively affect their general physical, social, and psycho-social status. The purpose of this study was to examine association with physical activity, sedentary life time and health-related quality of life in patients with COPD. Method: Of the total of 22,948 participants surveyed in Korean National Health and Nutrition Examination Survey (KNHANES 2013-2015), 8,626 participants were used for this study. Of these, under 40 years, over 80 years, missing values and abnormal values were excluded. Study variables included physical activity level, sedentary time and health-related quality of life variables. The physical activity level assessment tool was measured using International Physical Activity Questionnaire (IPAQ). Sedentary time referred to the amount of sitting time without moving the body. EQ-5D (Euro Quality of Life-5 Dimensions) was used as an index of health-related quality of life. Control variables were age, gender, income level, education level, marital status, comorbidity, smoking, BMI, cough, sputum, COPD severity. For this study, descriptive analysis, T-test, ANOVA and multivariate regression analysis were performed. Results: Of the 1,092 patients with COPD, 76.1% (n=831) were male and 23.9% (n=261) were female, while 39.0% (n=2,939) were male and 61.0% (n=4,595) were female in the comparison group without COPD. The COPD group with high level of physical activity showed a high level of EQ-5D scores ($0.9349{\pm}0.11$, p <0.001). Among patients with COPD, after adjusting for control variables, physical activity and sedentary time (physical activity level, Β=0.047, p <.001), (sedentary time, Β=-0.017, p <.05) were associated with health-related quality of life. Conclusion: Patients with COPD have a higher quality of life as their physical activity increases and the quality of life decreases as the time spent sitting increases. This study suggests that public health experts should consider improving COPD patient physical activity.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 1999년도 특별강연 및 추계학술발표대회 개요집
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• pp.142-145
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• 1999

The dynamic resistance monitoring is one of the important issues in that in-process and real time quality assurance of resistance spot weld is needed to increase the product reliability. Secondary dynamic resistance patterns, as a real manner, are hard to adapt those factors in real time and in-plant system. In the present study, a new dynamic resistance detecting method is presented as a practical manner of weld quality assurance at the primary circuit. By the correlation analysis, it is found that the primary dynamic resistance patterns are basically similar to those of the secondary. Various dynamic resistance indices are characterized with the primary curve. And quality of the weld, like the tensile shear strength, is estimated using adaptive neuro-fuzzy estimation system which is consisted of the Sugeno fuzzy algorithm. Through the fuzzy clustering and parameter optimization, real time weld quality assurance system with less efforts is proposed.