• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.4
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• pp.754-763
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• 2001

The purpose of this study was to examine: 1) the differences in the automation level by company characteristics(i.e., product category, product type, firm size); 2) the effects of company context(i.e., environmental uncertainty, task uncertainty) on the automation level; and 3) the effect of the automation level on manufacturing performance(i.e., quality, flexibility, time, cost). Data were collected from a mail survey. Four hundred eighty two questionaries were mailed to apparel manufacturers nationwide, and 60 responses were analyzed. The results revealed that: 1) mens and womens wear manufacturers and large manufacturers(i.e., the number of employees, sales volume) showed higher automation level; 2) environmental complexity positively affected the automation level; and 3) the automation level had a positive effect only on quality performance.

• International Journal of Precision Engineering and Manufacturing
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• v.5 no.4
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• pp.61-68
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• 2004

Necessity to address engineering system uncertainties in design processes has long been acknowledged. To obtain quality of product, a safety factor is traditionally used by many design engineers due to its easy of use and comprehension. However, the safety factor approach often yields either conservative or unreliable designs, since it ignores the type of probability distribution and the mechanism of uncertainty propagation from the input to the output. For a consistent reliability-based design, two fundamental issues must be investigated thoroughly. First, the design-decision process that clearly identifies a mechanism of uncertainty propagation under system uncertainties needs to be developed, which must be an efficient and accurate process. To identify the mechanism more effectively, an adaptive probability analysis is proposed by adaptively setting probability levels through a posteriori error estimation. The second is to develop the design process that not only yields a high quality design but also a cost-effective optimum design from manufacturing point of view. As a result, a response surface methodology is specially developed for RBDO, thus enhancing numerical challenges of efficiency and complicatedness. Side crashworthiness application is used to demonstrate the integrated design process for product and manufacturing process design.

• International Journal of Precision Engineering and Manufacturing
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• v.3 no.3
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• pp.5-11
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• 2002

This paper describes the methods for calibration and evaluation of the relative expanded uncertainty of a multi-axis force/moment sensor. In order to use the sensor in the industry, it should be calibrated and its relative expanded uncertainty should be also evaluated. At present, the confidence of the sensor is shown with only interference error. However, it is not accurate, because the calibrated multi-axis force/moment sensor has an interference error as well as a reproducibility error of the sensor, etc. In this paper, the methods fur calibration and for evaluation of the relative expanded uncertainty of a multi-axis force/moment sensor are newly proposed. Also, a six-axis force/moment sensor is calibrated with the proposed calibration method and the relative expanded uncertainty is evaluated using the proposed uncertainty evaluation method and the calibration results. It is thought that the methods fur calibration and evaluation of the uncertainty can be usually used for calibration and evaluation of the uncertainty of the multi-axis force/moment sensor.

• KDI Journal of Economic Policy
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• v.27 no.2
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• pp.89-121
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• 2005

This paper investigates the empirical relationship between investment and uncertainty using the firm level data of Korean manufacturing sector. Empirical results show that uncertainty is negatively correlated with investment only for the post-crisis sample period. In particular, the negative effect of uncertainty on investment is more significant for low interest coverage ratio firms, high debt-asset ratio firms and small firms. The results are consistent with the claim that firms act in a more risk-averse manner after the financial crisis. This paper also finds a significant sensitivity of investment to cash flows only for the pre-crisis sample period, suggesting that financial constraint is not relatively important in explaining low investment after the financial crisis.

• International Commerce and Information Review
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• v.16 no.1
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• pp.163-183
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• 2014

This paper empirically investigated whether the strategic performance of dependence and commitment on output sector uncertainty based on the data from manufacturing firms in Korea. U.S. Also, the proposed model was proven by the structural equation model with the data gathered from 105 manufacturing firms in Korea, 103 in U.S. The success of the members of channel having limited resources and capabilities depends on how they cope with environment. Especially, it is insispensable for manufacturing firms and distributing firms to build up win win systems when environmental uncertainty is high in the output sector. The findings were as follows. Hypothesis 1 was accepted in all the nations. Hypothesis 2 was accepted in the United States yet not in Korea. Hypothesis 3, 4 was accepted in Korea yet not in the United States. Hypothesis 5 was accepted in every nation as well. In the future, the dependence, commitment and strategic performance of manufacturing and distribution firms should be investigated from a mutual perspective, and additional data should be obtained by selecting more subjects. As for environmental uncertainty, the uncertainty of distribution environments as well as output sector uncertainty should equally be investigated by making a comparative analysis.

• Steel and Composite Structures
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• v.7 no.3
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• pp.253-262
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• 2007

A methodology to design symmetrically laminated fibre-reinforced structures under transverse loads for minimum weight, with manufacturing uncertainty in the ply angle, is described. The ply angle and the ply thickness are the design variables, and the Tsai-Wu failure criteria is the design constraint implemented. It is assumed that the probability of any tolerance value occurring within the tolerance band, compared with any other, is equal, and thus the approach is a worst-case scenario approach. The finite element method, based on Mindlin plate and shell theory, is implemented, and thus effects like bending-twisting coupling are accounted for. The Golden Section method is used as the search algorithm, but the methodology is flexible enough to allow any appropriate finite element formulation, search algorithm and failure criterion to be substituted. In order to demonstrate the procedure, laminated plates with varying aspect ratios and boundary conditions are optimally designed and compared.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.22 no.51
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• pp.63-72
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• 1999

Many firms have applied flexible manufacturing systems as a means of increasing productivity, profitability, and quality. Therefore, the purpose of this paper is to develop the more efficient justification model through an analytical scoring model with the quantitative factors, flexibility factors, and safety factors under uncertainty. In this paper, the three factors for properly comparing and evaluating of flexible manufacturing systems are presented. Especially, this paper has emphasized the flexibility and safety factor; the one consists of organization assessment, process treatment function, products and products quantity, useful life assesment, and software function, the other presents risk assesment, Y2K problem, safety device analysis, total productive management system, safety management. Finally, a normalized scoring model by the new flexibility and safety factors can be used in real fields for flexible manufacturing systems project selection under uncertainty.

• International Commerce and Information Review
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• v.14 no.4
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• pp.253-273
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• 2012

The purpose of this study was to examine the impact of the uncertainty of competitive environments on the commitment of manufacturing firms with distribution firms, their trust and long-term orientation in Korea, the United States and Japan. This study is of great significance in that it attempted to make a comparative analysis of the uncertainty of competitive environments among the three nations by selecting subjects not only from Korea but from the United States and Japan. A survey was conducted on the selected manufacturing firms, and the data from 105 Korean firms, 103 American companies and 83 Japanese firms were gathered. A structural equation was utilized to analyze the collected data. The findings of the study were as follows: Hypothesis 1 was rejected in Korea and Japan and was accepted in the United States. Hypothesis 2 was accepted in Korea yet not in the United States and Japan. Hypothesis 3 was accepted in all the nations. Hypothesis 4 was rejected in Korea and the United States and was accepted in Japan. Hypothesis 5 was accepted in all the nations, and Hypothesis 6 was accepted in every nation as well. In the future, the commitment, trust and long-term orientation of manufacturing and distribution firms should be investigated from a mutual perspective, and additional data should be obtained by selecting more subjects. As for environmental uncertainty, the uncertainty of distribution environments as well as competitive environments should equally be investigated by making a comparative analysis.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2003.04a
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• pp.229-233
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• 2003

Theodolite measurement system is non-contacted 3-dimensional measurement system. The system accuracy is 0.5 mm or better for distance 0 ~ 100m. And the system is used for a product of middle and large scale. This study is performed for the measurement uncertainty of the system. We could know that the main uncertainty factors are temperature, illumination and skill. And, we perform the study for the effect according to the height difference of scale bar. And, we calculated the measurement uncertainty with those factors.

• Journal of Information Technology Applications and Management
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• v.11 no.2
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• pp.81-99
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• 2004

Manufacturing flexibility has strategic position in improving competitive advantage as a mechanism that responses environmental uncertainty. Thus this study aims at recognizing strategic meaning of manufacturing flexibility in enhancing the competitive advantage and measuring manufacturing flexibility and ultimately analyzing the effects of IT use on the manufacturing flexibility. Consequently we proved that IT use have an effect on manufacturing flexibility and manufacturing flexibility has an effect on competitive advantage in this study The results of this study are as follows. First, information acquisition and decision support by IT use has a significant effect on enhancing the manufacturing flexibility and manufacturing flexibility has a significant effect on improving the competitive advantage. Theses results are also means that IT use to support AMT usage is more important than AMT itself in the achieving manufacturing flexibility.