• Journal of the Korean Society of Manufacturing Process Engineers
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• v.5 no.1
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• pp.27-32
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• 2006

Thermoplastic elastomer(TPE) has many advantages such as high flexibility, high elasticity and high elongation, etc. TPE is easily molded as plastic materials, therefore, many TPE parts are applied as home appliances and mechanical parts. However, its mechanical properties would be changed by injection molding conditions such as melt temperature, mold temperature, injection pressure and holding pressure, etc. In this study, the influences of the injection molding condition on the mechanical properties as tensile strength, hardness of thermoplastic vulcanizates(TPVs), which is one of the TPE, were investigated. By the injection molding experiment, the molding's tensile strength and hardness was influenced on the melt temperature and composition ratio of PP and EPDM. The morphology of moldings were shown by the scanning electron microscope.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.3 no.2
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• pp.39-45
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• 2004

Generally industrial multi-articulated robots are used for parts assembly, welding, and painting processes. The high flexibility of them is very useful to not only parts assembly, welding, and painting processes, but also machining processes. But because of machining processes to need a high stiffness of machine structure, so machining is usually not tried at them, except deburring processes now. During past three years the works are carried out to improve the stiffness of a industrial multi-articulated robot With some gas spring as a first idea in this research area. As a result of that stiffness was significantly up, and found and investigated the machining possibility at it.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.04a
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• pp.235-240
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• 2004

The equipment of industrial robot in manufacturing and assembly lines has rapidly increased. In order to achieve high productivity and flexibility, it becomes very important to develop the visual feedback control system with Off-Line Programming System(OLPS). We can save much efforts and time in adjusting robots to newly defined workcells by using OLPS. A proposed visual calibration scheme is based on position-based visual feedback. The calibration program firstly generates predicted images of objects in an assumed end-effector position. The process to generate predicted images consists of projection to screen-coordinates, visible range test and construction of simple silhouette figures. Then camera images acquired are compared with predicted ones for updating position and orientation data. Computation of error is very simple because the scheme is based on perspective projection which can be also expanded to experimental results. Computation time can be extremely reduced because the proposed method does not require the precise calculation of tree-dimensional object data and image Jacobian.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.5
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• pp.112-118
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• 2000

In case ESO(evolutionary structural optimization) which is one of topology optimization methods, the element removal ratio is fixed throughout topology optimization by 1 or 2%. As a result it has no flexibility for various types of structures and thus the rate of convergence might not be efficient. Thus various element removal methods were developed in order to improve the efficiency of ESO. In this paper, various element removal methods for ESO are compared with each other for a bracket and a short cantilever. In addition, a new improved bi-directional element removal method is suggested in order to obtain much better optimized topology. From the comparative results of the examples, it is verified that all of the developed various element removal methods are very effective, and the suggested element removal method is the most effective.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.2
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• pp.202-207
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• 2012

Multi-stage deploying beams are useful for transporting parts or products handling in production lines. However, such multi-stage beams are often exposed to unwanted vibration due to the presence of their flexibility and time-varying properties. This paper is concerned with dynamic modeling and analysis of 2-stage axially deploying beams under gravity by using the finite element method. A variable domain finite element method is employed to develop the dynamic model. A rigorous method to account for engagement of two-stage beams during the deploying procedure is introduced by breaking the entire domain into three variable domains. Several deploying strategies are tested to analyze the residual vibrations. Several examples are illustrated to investigate the self-induced damping and the effects of deploying strategy on the vibrations.

• Asia pacific journal of information systems
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• v.7 no.1
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• pp.151-163
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• 1997

This paper deals with a reference model for a process-oriented parts supply company From the view point of SCM(Supply Chain Management), the model focuses on the integration of order management and manufacturing information. The model, considering the characteristics of manufacturing processes, separates the execution level from the planning level, and then introduces a virtual process to efficiently link the two levels. The model is operated to maximize its flexibility by the separation of planning and execution. A case study shows that our model significantly increases the productivity of the company.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.34 no.1
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• pp.42-51
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• 2011

Poisson model and Gamma-Poisson model are popularly used to analyze statistical behavior from defective data. The methods are based on binary criteria, that is, good or failure. However, manufacturing industries prefer polytomous criteria for classifying manufactured products due to flexibility of marketing. In this paper, I introduce two multivariate Gamma-Poisson(MGP) models and estimation methods of the parameters in the models, which are able to handle polytomous data. The models and estimators are verified on defective pixels of LCD manufacturing. Experimental results show that both the independent MGP model and the multinomial MGP model have excellent performance in terms of mean absolute deviation and the choice of method depends on the purpose of use.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1997.10a
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• pp.11-14
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• 1997

Flexibility and efficiency in producing a large number of productions in small-to-medium lot sizes are necessary to be competitive. Many firms are concerned about cellular manufacturing system(CMS) to surmount the abrupt change in management environment and to innovate their manufacturing systems. The purpose of this study 1) align BPR with CMS, 2) present the methodology for constructing a CMS and 3) apply to a firm ad verify it. The results of this paper are to present 1) the systematic methodology for constructing CMS at first in our country, 2) the methodology integrating managerial aspects, technological aspects and behavioral aspects, 3) the customer-oriented methodology based on customer value.

• International Journal of Quality Innovation
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• v.10 no.2
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• pp.57-76
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• 2009

Although many adherents openly praise the importance of quality management practices (QMP) in organisations, others have identified significant costs and implementation obstacles. Some recent studies showed that QMP have failed due to the ignorance of quality cultures. How to improve the success rate of QMP in organisations has become a critical issue both in the academy and in practice. This paper discusses the common enablers of and cultural impacts on QMP. It explores the dimensions of national versus organisational culture, and identifies the main features of four quality culture models as advocated in the literature in relation to facilitating QMP in organisations. It was found that flat structures, decentralised functions, empowerment, flexibility, innovation, limited rules and regulations and teamwork favor the QMP implementation. For facilitating culture changes for QMP, values associated with low power distance, low uncertainty avoidance and collectivism would have to be nurtured. Further research is needed to incorporate the findings and develop a practical quality culture approach for real applications in industry.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.3
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• pp.79-86
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• 2011

The dynamic instability and natural frequency of elastically restrained pipe conveying fluid with the attached mass and crack are investigated. The pipe system with a crack is modeled by using extended Hamilton's Principle with consideration of bending energy. The crack on the pipe system is represented by a local flexibility matrix and two undamaged beam segments are connected. In this paper, the influence of attached mass, its position and crack on the dynamic stability of a elastically restrained pipe system is presented. Also, the critical flow velocity for the flutter and divergence due to the variation in the position and stiffness of supported spring is studied. Finally, the critical flow velocities and stability maps of the pipe conveying fluid with the attached mass are obtained by the changing parameters.