• Journal of Korean Society of Industrial and Systems Engineering
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• v.25 no.4
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• pp.69-78
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• 2002

The basic purpose of the JIT(Just In Time) production system is to increase profits by reducing costs-that is, by completely eliminating waste such as excessive stocks or workforce. To achieve cost reduction, Production must promptly and flexibly adapt to changes in market demand without having wasteful slacks. :iuch an ideal is accomplished by the concept of JIT, producing the necessary items in the necessary quantities at the necessary time. The JIT production system is supported by the following: reduction of setup time, smoothing of production, standardization of jobs, improvement activities, design of machine layout, Kanban system, autonomation etc. This study examined the present state of the domestic JIT production system and introduced the empirical case of JIT application a small and medium manufacturing company. A synthetic resins manufacturing company applied JIT principles to its processes and achieved the great performance.

• Korean Journal of Human Ecology
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• v.5 no.2
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• pp.53-72
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• 1996

This article reviewed the research on factors associated with marital quality and stability. Three major categories of factors were described, including background and context, individual traits and behaviors, and couple interactional processes. This review highlighted findings from cross-sectional and longitudinal studies of the prediction of marital quality and stability. Particular attention was given to marital instruments and procedures that had a solid empirical foundation for understanding the concepts related to measure of marital quality and stability. Also, empirically based intervention programs that had been designed to prevent marital distress and divorce were investigated to figure out the relationship between communication factors and conflict resolution styles. Finally, three theoretical frameworks were drawn from empirical literatures, marital measurment instruments, and programs for marital strength to predict factors associated with the marital quality and stability. Recommendations for future research and implications were described.

• 한국연소학회:학술대회논문집
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• 2012.04a
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• pp.217-219
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• 2012

This study describes 3D RANS simulation of a 2.1 MW swirling pulverized coal flame in a semi-industrial scale furnace. The simulation of pulverized coal combustion involves various models for complex physical processes and needs information of pyrolysis rate, the yields and compositions of volatiles and char especially in coal conversion. The coal conversion information can be acquired by the experiment or the pre-processor code. The empirical model based on the experiment of the IFRF and the structural model based on the pre-processor code of the PC-COAL-LAB were evaluated against the measurement data.

• Asian Journal of Innovation and Policy
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• v.1 no.1
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• pp.50-70
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• 2012

This paper analyzes the factors that determine technology innovation in Korean manufacturing firms, focusing on the role of intra-firm knowledge diffusion and market strategy in patent production. For empirical analysis, zero-inflated negative binomial (ZINB) regression is applied to the 2009 Human Capital Corporate Panel data. The empirical findings confirm the critical role of intra-firm knowledge-sharing processes in technology innovation; firms with a market-leading strategy oriented to new product development also tend to be prolific in patent production.

• Journal of Korean Institute of Industrial Engineers
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• v.42 no.2
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• pp.80-85
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• 2016

This study suggests a process design using cognitive processes. Job characteristic model for job design and recent cognitive engineering studies for process design are reviewed briefly. By using these concepts, the lean production system is re-interpreted in terms of cognitive engineering and the latent dimensions of the lean production system are revealed as the application of cognitive engineering principles. An integrated process design framework for cognitive manufacturing system using job characteristic model is suggested for the effective design of manufacturing system. Propositions for empirical analysis of this model are also analyzed through a questionnaire survey. Propositions are (1) experiential cognition and motivation potential affect the ability, role perception, and need for achievement of the operator in the manufacturing system, (2) the ability, role perception, and need for achievement of the operator affect the job performance. Both propositions are supported by correlation analysis and path analysis.

• Journal of Korean Society for Quality Management
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• v.8 no.1
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• pp.3-7
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• 1980

In many industrial processes, there are more than two responses (i.e., yield, percent impurity, etc.) of interest, and it is desirable to determine the optimal levels of the factors (i.e., temperature, pressure, etc.) that influence the responses. Suppose the response relationships are assumed to be approximated by second-order polynomial regression models. The problems considered in this paper is, first, to propose how to select polynomial terms to fit the multivariate regression surfaces for a given set of data, and, second, to propose how to analyze the data to obtain an optimal operating condition for the factors. The proposed techniques were applied for empirical process optimization in a tire company in Korea. This case is presented as an illustration.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.90-90
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• 2011

Long-term nonstationary oscillations (NSOs) are commonly observed in hydrological and climatological data series such as low-frequency climate oscillation indices and precipitation dataset. In this work, we present a stochastic model that captures NSOs within a given variable. The model employs a data-adaptive decomposition method named empirical mode decomposition (EMD). Irregular oscillatory processes in a given variable can be extracted into a finite number of intrinsic mode functions with the EMD approach. A unique data-adaptive algorithm is proposed in the present paper in order to study the future evolution of the NSO components extracted from EMD.

• The Journal of the Korea Contents Association
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• v.19 no.3
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• pp.539-547
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• 2019

This study investigated the effect of small-world structure in team processes on team performance. I discussed the theoretical relationship between small-world structure in team processes and team performance and analyzed the relationship using pass data of soccer teams. I constructed the 128 pass networks from the pass data of the 2014 FIFA World Cup and then measured the structural features indicating small-world structure of the networks. Correlation analysis and regression analysis were performed in order to examine the strength and direction of the relationship. According to the results, the clustering has an exponential relationship with team performance and the connectivity has a log-function relationship with team performance. Finally, I found the positive effect of small-world structure in team processes on team performance. Through theoretical discussion and empirical analysis, this study found that small-world structure in team processes increase team performance by facilitating task coordination and collaboration between team members.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.26 no.2
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• pp.85-92
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• 2020

In this study, the relationship between packaging design and logistics efficiency raised in prior research was to be conducted through empirical analysis in terms of SCM efficiency. The main research contents were carried out in the pursuit of efficiency of the relevant store operation, relationship with SCM efficiency aspects, resolution of differences in recognition between manufacturers and distributors, establishment of automated systems for RRP production facilities and processes in the manufacturer's facilities, logistics costs, environment and quality safety, and promotion of RRP through the manufacturer's packaging system. As a result of the verification of SCM efficiency aspects through this study, logistics efficiency will be reduced in the case of the packaging system or delivery system, where only the operational efficiency of the store is the top priority(χ² = 178.500, p < 0.001). This is because of the strong interaction between packaging and supply chain activities, many packaging systems affect the performance criteria of the supply chain, and the content that packaging personnel should ensure that the packaging system meets other essential requirements while meeting the primary goal of protecting the product is also a result consistent with the preceding study. An analysis of whether the RRP promotion through the manufacturer's packaging system would result in improved loading efficiency showed that there was a statistically meaningful difference at a significant level of 0.000, as χ² = 140.133.

• International Journal of Naval Architecture and Ocean Engineering
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• v.11 no.2
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• pp.939-951
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• 2019

A novel empirical mode decomposition strategy based on Fourier transform and band-pass filter techniques, contributing to efficient instantaneous vibration analyses, is developed in this study. Two key improvements are proposed. The first is associated with the adoption of a band-pass filter technique for intrinsic mode function sifting. The primary characteristic of decomposed components is that their bandwidths do not overlap in the frequency domain. The second improvement concerns an attempt to design narrowband constraints as the essential requirements for intrinsic mode function to make it physically meaningful. Because all decomposed components are generated with respect to their intrinsic narrow bandwidth and strict sifting from high to low frequencies successively, they are orthogonal to each other and are thus suitable for an instantaneous frequency analysis. The direct Hilbert spectrum is employed to illustrate the instantaneous time-frequency-energy distribution. Commendable agreement between the illustrations of the proposed direct Hilbert spectrum and the traditional Fourier spectrum was observed. This method provides robust identifications of vibration modes embedded in vibration processes, deemed to be an efficient means to obtain valuable instantaneous information.