• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1994.10a
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• pp.157-164
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• 1994

Finite element analysis of material deformation is successfully utilized to understand metal forming processes such as forging, extrusion and deep drawing. However, such analysis involves contact problems; a free node touches a die surface and a contact node slips along the die surface. In the present investigation, appropriate contact algorithms were developed assuming that a three dimensional surface can be divided into bilinear patches and that nodal velocities are linear during an incremental time. The algorithms were coded into a computer program and tested for a simple surface. Comparison of the test result with that obtained from a commercial code is presented and discussed.

• Journal of the Korean Society of Industry Convergence
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• v.3 no.3
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• pp.201-207
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• 2000

In this study, methodologies for checking the interference between in-core instrumentation (ICI) guide tubes for routing of ICI guide tubes in the reactor coolant system of typical Pressurized Water Reactor under cold and normal operation (NOP) conditions are presented. The closest points of ICI guide tubes under cold condition are calculated by using minimize technique and are used as data for NOP analysis. Movements of ICI guide tubes under NOP condition are performed by the commercial computer code, SUPERPIPE.

• 연구논문집
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• s.25
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• pp.5-12
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• 1995

Mold platen are one of the most important structural components of the injection molding machine. Mold platen had been designed, and manufactured based on the experience and the method of trial and error. Recently, as the computer progress, the numerical simulation method using commercial finite element analysis code has been used to analyze the characteristics of components. It's a urgent problem to reduce the weight of mold platen while preserving the safety and reliability for the structual failure. Finite element analyses to establish basic design technologies and reducing the weight of mold platen were carried out. As result, we are obtained the about 10% reducing the weight for mold platen.

• Journal of the Semiconductor & Display Technology
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• v.5 no.2 s.15
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• pp.11-14
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• 2006

A new reset waveform with negative ramp pulse is proposed. Conventional reset waveform applied to the commercial PDP uses a positive ramp pulse. The reset waveforms, especially focused on ramp area, were examined with 2 dimensional fluid code. The proposed negative reset waveform showed much lower ignition voltage ($\sim$70V) as compared with the conventional reset waveform. When the negative ramp pulse was applied, all of the positive-charged ions are collected on the scan electrode. It is found that the ignition voltage of reset discharge due to the negative ramp pulse became lower than that of positive ramp discharge.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.569-574
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• 2002

As consumer's desire becomes various, agility of mold manufacturing is most important factor for competence of manufacturer. In common works to use commercial CAM system to generate tool path, some decision making process is required to produce optimal result of CAM systems, The paper proposes a methodology for computer-assisted tool selection procedures for various cutting type, such as rough, semi-rough and finish cuts. The system provides assist-tool-items for machining of design model part of injection meld die by analyzing sliced CAD model of die cavity and core. Also, the generating NC-code of the tool size is used to calculate machining time. The system is developed with commercial CAM using API. This module will be used for optimization of tool selection and planning process.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.1
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• pp.118-125
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• 2003

As consumer's desire becomes various, agility of mold manufacturing is the most important factor for competitive mold manufacturer. Decision making process is required to produce optimal result of CAM systems in using commercial CAM system to generate tool path. The paper proposes a methodology fur computer-assisted tool selection procedures for various cutting type of rough, semi-rough and finish cuts. The procedure provides assistance for machining tool selection by analyzing sliced CAD model section of die cavity and core. Information about machining time for the generated NC-code is used to aid the tool selection. The module is developed with commercial CAM API. This module will be used fur the optimization of tool selection and planning process.

• International Journal of CAD/CAM
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• v.9 no.1
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• pp.121-128
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• 2010

The purpose of this study is to clarify the mechanical behavior of human lumbar vertebrae (L3/L4) with and without fusion bone under physiological axial compression. The author has developed the program code to build the patient specific three-dimensional geometric model from the computed tomography (CT) images. The developed three-dimensional model provides the necessary information to the physicians and surgeons to visually interact with the model and if needed, plan the way of surgery in advance. The processed data of the model is versatile and compatible with the commercial computer aided design (CAD), finite element analysis (FEA) software and rapid prototyping technology. The actual physical model is manufactured using rapid prototyping technique to confirm the executable competence of the processed data from the developed program code. The patient specific model of L3/L4 vertebrae is analyzed under compressive loading condition by the FEA approach. By varying the spacer position and fusion bone with and without pedicle instrumentation, simulations were carried out to find the increasing axial stiffness so as to ensure the success of fusion technique. The finding was helpful in positioning the fusion bone graft and to predict the mechanical stress and deformation of body organ indicating the critical section.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.16
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• pp.331-359
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• 2001

Uniform Electronic Transactions Act (1999) Drafted by the National Conference of Commissioners on Uniform State Laws. The Act allows the use of electronic records and electronic signatures in any transaction, except transactions subject to the Uniform Commercial Code. The fundamental purpose of this act is to remove perceived barriers to electronic commerce. The Act's a procedural statute. It does not mandate either electronic signatures or records, but provides a means to effectuate transactions when they are used. The primary objective is to establish the legal equivalence of electronic records and signatures with paper writings and manually-signed signatures. With regard to the general scope of the Act, the Act's coverage is inherently limited by the definition of "transaction." The Act does not apply to all writings and signatures, but only to electronic records and signatures relating to a transaction, defined as those interactions between people relating to business, commercial and governmental affairs. The exclusion of specific Articles of the Uniform Commercial Code reflects the recognition that, particularly in the case of Articles 5, 8 and revised Article 9, electronic transactions were addressed in the specific contexts of those revision processes. In the context of Articles 2 and 2A the UETA provides the vehicle for assuring that such transactions may be accomplished and effected via an electronic medium. At such time as Articles 2 and 2A are revised the extent of coverage in those Articles(Acts) may make application of this Act as a gap-filling law desirable. Similar considerations apply to the recently promulgated Uniform Computer Information Transactions Act (UCITA). Another fundamental premise of the Act is that it be minimalist and procedural. The general efficacy of existing law, in an electronic context, so long as biases and barriers to the medium are removed, confirms this approach. The Act defers to existing substantive law. Specific areas of deference to other law in this Act include: i) the meaning and effect of "sign" under existing law, ii) the method and manner of displaying, transmitting and formatting information in section 8, iii) rules of attribution in section 9, and iv) the law of mistake in section 10.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2007.05a
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• pp.209-212
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• 2007

Rubber compounds have high viscoelastic property. One of the viscoelastic behaviors during profile extrusion is the swelling of extrudate. In this study, die swell of rubber compounds at the capillary die have been investigated through an experiment and computer simulation. They have been performed using fluidity tester in experiment and commercial CFD code, Polyflow in computer simulation. Die swell of rubber compounds for relaxation time at several modes under same conditions with the experiment were predicted using non-linear differential viscoelastic model, Phan-Thien-Tanner (PTT) model. The simulation was analyzed compared with the experiment. Viscoelastic behaviors for pressure, velocity and shear rate distribution were analyzed at the capillary die. It is concluded that the PTT model successfully represented the amount of the optimal die swell of rubber compounds for relaxation time at different modes.

• Proceedings of the KIEE Conference
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• 2008.04a
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• pp.65-66
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• 2008

A vector DLL represents signal tracking scheme utilizing navigation results, and it has been known that it has better performance than a conventional scalar DLL. This paper discusses the structure and conceptual benefits of the vector DLL, and describes implementation of the vector DLL in a software GPS receive. Also, the benefits of the vector DLL are confirmed by an experiment. Through the experiment, the code tracking accuracy between the vector DLL and a scalar DLL implementation is compared in static environments, and the navigation accuracy is analyzed using GPS signals received from a commercial GPS simulator.