• Journal of the Korea Society for Simulation
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• v.14 no.4
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• pp.55-68
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• 2005

The advancement in semiconductor technology is leading toward smaller critical dimension designs and larger wafer manufactures. Due to such phenomena, semiconductor industry is in need of an accurate control of the process. Photolithography is one of the key processes where the pattern of each layer is formed. In this process, precise superposition of the current layer to the previous layer is critical. Therefore overlay parameters of the semiconductor photolithography process is targeted for this research. The complex relationship among the input parameters and the output metrologies is difficult to understand and harder yet to model. Because of the superiority in modeling multi-nonlinear relationships, neural networks is used for the simulator modeling. For training the neural networks, conjugate gradient method is employed. An experiment is performed to evaluate the performance among the proposed neural network simulator, stepwise regression model, and the currently practiced prediction model from the test site.

• Journal of the Korean Society for Precision Engineering
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• v.34 no.1
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• pp.23-27
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• 2017

This paper aims to develop a prediction model for the product quality of a casting process. Prediction of the product quality utilizes an artificial neural network (ANN) in order to renovate the manufacturing technology of the root industry. Various aspects of the research on the prediction algorithm for the casting process using an ANN have been investigated. First, the key process parameters have been selected by means of a statistics analysis of the process data. Then, the optimal number of the layers and neurons in the ANN structure is established. Next, feed-forward back propagation and the Levenberg-Marquardt algorithm are selected to be used for training. Simulation of the predicted product quality shows that the prediction is accurate. Finally, the proposed method shows that use of the ANN can be an effective tool for predicting the results of the casting process.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2006.11a
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• pp.303-306
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• 2006

Systems engineering is an interdisciplinary approach encompassing the entire technical effort to evolve and verify an integrated and total Life cycle balanced set of system, people, and process solutions that satisfy customer needs. Systems engineering is the integrating mechanism across the technical efforts related to the development, manufacturing, verification, deployment, operations, support, disposal at and user training for systems and their life cycle processes (EIA/IS 632). This paper introduces the principles and processes of systems engineering, based on EIA/IS 632, as a methodology for the development of large-complex marine systems.

• International Journal of Safety
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• v.4 no.1
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• pp.32-37
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• 2005

This study was conducted to identity the characteristics of occupational health and safety management systems around the world, to survey the implementation of OHSMS in Korean companies, to find problems and corrective measures, and to understand the opinions of top management about OHSMS. Questionnaires on the operation of occupational health and safety management systems in Korean manufacturing companies were carried out. Occupational health and safety management systems around the world, including OHSAS 18001, BS8800, KOSHA 18001, VPP, J-OHSMS, were reviewed. In order to implement an occupational health and safety management system successfully, it was found that the management should consider occupational health and safety as important, provide employees with necessary training, and have a strong commitment to occupational health and safety.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.04a
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• pp.171-175
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• 2000

Neural networks are in the framework of sensorbased tracking control of robot manipulators. They learn by practice movements the relationship between PSD (an analog Position Sensitive Detector) sensor readings for target positions and the joint commands to reach them. Using this configuration, the system can track or follow a moving or stationary object in real time. Furthermore, an efficient neural network architecture has been developed for real time learning. This network uses multiple sets of simple backpropagation networks one of which is selected according to which division (corresponding to a cluster of the self-organizing feature map) in data space the current input data belongs to. This lends itself to a very training and processing implementation required for real time control.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.10a
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• pp.309-314
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• 2004

A flexible disk grinding system process has been introduced that utilized varying disk orientation with respect to workpiece along with the applied feed speed. Various process conditions including cutting speed, maximum feed speed and orientation angles could applied to observe process outcomes. Even though continuous and constant feed speed has been applied to the process, the results from the trapezoidal input velocity profiles would be observed and compared. Based on the control strategies including neural network methodologies, several output results were compared to find the optimum process condition. Two axis control results were displayed showing better performance with higher trajectory error for larger training epoch.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.10a
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• pp.108-112
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• 2000

Neural networks are used in the framework of sensorbased tracking control of robot manipulators. They learn by practice movements the relationship between PSD (an analog Position Sensitive Detector) sensor readings for target positions and the joint commands to reach them. Using this configuration, the system can track or follow a moving or stationary object in real time. Furthermore, an efficient neural network architecture has been developed for real time learning. This network uses multiple sets of simple backpropagation networks one of which is selected according to which division (corresponding to a cluster of the self-organizing feature map) in data space the current input data belongs to. This lends itself to a very training and processing implementation required for real time control.

• Journal of the Korea Furniture Society
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• v.11 no.2
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• pp.13-23
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• 2000

Our furniture industry is rapidly changing due to the declining economy. The existing weak furniture industry in Korea has yielded its inability to complete in a very competitive marketplace. The furniture companies lack the special necessary skills and professional knowledge necessary to design and manufacture furniture. Therefore, constant effort by designers and managers is needed in order to strengthen the Korean furniture industry's strategy and advance it into becoming a recognized player in the area of furniture design, worldwide, Designers has to have systematic training in order to have insight into upcoming international trends and incorporate new manufacturing techniques immediately This study will analyze the curriculums related to furniture design departments in Universities and technical schools in Germany, a leader in the furniture industry. It will present new educational ideas and program for furniture designers in the Korean universities.

• Journal of the Korean Home Economics Association
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• v.30 no.3
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• pp.79-89
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• 1992

Indicies of the labor productivity were assessed from 80 industry foodservice erstablishments in terms of meals served per labor hour, labor minutes per meal served, and labor cost per meal served. The labor productivity indicies were also assessed according to variables related to work such as working hours, paryment for the workers, volume of feeding, utilization of foodservice equipment, use of processed foods, and background of employees. The summary of the results was as follows: 1. Manufacturing sector among surveyed industry foodservice showed the highest labor productivity indicies followed by training institute. 2. 28.8% of surveyed establishments used dishwashing machine, while manual dishwashing was used in 71.3% of subjects, equipped rate point was 9.8 out of 20, and disposable dish was used in 30% of subjects. 3. A significant positive relationship was found between the number of meals and the labor procductivity indicies. As the number of meals increased, more meals were served per worker as per labor hour. 4. A significant negative relationship was found between price of meal and the labor productivity didicies. As the price of meal increased, less meals were served per worker as well as per labor hour.

• Proceedings of the Safety Management and Science Conference
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• 2011.04a
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• pp.309-317
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• 2011

Data were collected from employees(N=155) working in manufacturing industry to assess the impact of safety climate on job satisfaction, organizational citizenship behavior, and intention to turnover. Subordinate dimensions of the safety climate measured in our study were management value, immediate supervisor, safety communication, safety training, and safety practice. The results show that management value and immediate supervisor, of safety climate's dimensions, impact on job satisfaction and organizational citizenship behavior. Intention to turnover was influenced by only immediate supervisor.