• Journal of Ocean Engineering and Technology
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• v.5 no.1
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• pp.64-70
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• 1991

The design theory of roller gate has been systematized laying more emphasis on practical formulas than theoretical ones and the design procedure of the existing gate facilites is reviewed and analyaed on economical viewpoint and safety factor. The design theory of timoshenko, the thechnical standards for hydraulic gate and penstock of Japan, and the design standards for waterworks structures of Germany are applied to the study of optimal design of a gate leaf. In this study, gate leaf which is now being operated for water control at the seadike, estuary dam and reservoir dam are adopted as a mode, and a new design method by the computer is proposed through the variation of design elements within practical ranges. As a result, safety factor and economical design can be made by using T-beams to the horizontal and vertical beam of the gate leaf instead of H-beams used in the existing seadike roller gate at Asan, and total weight of gate leaf is reduced by the present optimization.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.6
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• pp.127-132
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• 2001

An automatic design system for a hydraulic gate has been developed to cut down the time for the design calculation and to optimize its design. It is oriented to the radial gate which is the simplest, most reliable, least expensive and most widely used hydraulic gate. This system is composed of data input, strength computation and result display modules with databases of the properties of components and materials. In this development, the existing intricate design procedure has been changed to the straightforward procedure without assumption of weight. With this code, the design time of the radial gate could be reduced below one thirtieth in comparison with manual work and the optimum design could be accomplished easily.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.5
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• pp.263-267
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• 2016

In this paper, we analyzed the electrical characteristics of NPT planar and trench gate IGBT after designing these devices according to design and process parameter. To begin with, we have designed NPT planar gate IGBT and carried out simulation with T-CAD. Therefore, we extracted design and process parameter and obtained optimal electrical characteristics. The breakdown voltage was 724 V and The on state voltage drop was 1.746 V. The next was carried out optimal design of trench gate power IGBT. We did this research by same drift thickness and resistivity of planar gate power IGBT. As a result of experiment, we obtain 720 V breakdown voltage, 1.32 V on state voltage drop and 4.077 V threshold voltage. These results were improved performance and fabrication of trench gate power IGBT and planar gate Power IGBT.

• JSTS:Journal of Semiconductor Technology and Science
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• v.9 no.3
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• pp.136-147
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• 2009

In this paper we analyze the influence of source/drain (S/D) extension region design for minimizing short channel effects (SCEs) in 25 nm gate length single and double gate Silicon-on-Insulator (SOI) and Germanium-on-Insulator (GOI) MOSFETs. A design methodology, by evaluatingm the ratio of the effective channel length to the natural length for the different devices (single or double gate FETs) and technology (SOI or GOI), is proposed to minimize short channel effects (SCEs). The optimization of non-overlapped gate-source/drain i.e. underlap channel architecture is extremely useful to limit the degradation in SCEs caused by the high permittivity channel materials like Germanium as compared to that exhibited in Silicon based devices. Subthreshold slope and Drain Induced Barrier Lowering results show that steeper S/D gradients along with wider spacer regions are needed to suppress SCEs in GOI single/double gate devices as compared to Silicon based MOSFETs. A design criterion is developed to evaluate the minimum spacer width associated with underlap channel design to limit SCEs in SOI/GOI MOSFETs.

• Design & Manufacturing
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• v.17 no.1
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• pp.64-69
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• 2023

This paper explores the impact of gate shape changes on the size and density of foamed cells in microcellular foam injection molding. Five different gate shapes were examined while varying the amount of nitrogen gas(N2) injected for foaming. Analysis of the results showed that while average values did not change significantly, deviation values decreased by approximately 65% for cell size and 56% for density when 3.5wt% of nitrogen gas was injected in the film gate. Further analysis was conducted to verify this phenomenon, revealing that the contact area between the gate and product had the greatest impact. Our findings indicate that to ensure uniform generation of foamed cells in microcellular foaming product design, a gate with a wide contact area should be secured.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.2 no.2
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• pp.33-37
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• 2001

The synthesis of gates of injection-molded parts has been done empirically, since it requires profound knowledge about the gate design,. which is not available to designers through current CAD systems. GATEWAY is a knowledge module which contains knowledge to Permit non-experts as well as mold design experts to generate acceptable gate design of injection-molded parts. A knowledge-based CAD system is constructed by adding the knowledge module, GATEWAY, for gate synthesis and appropriate CAE programs for mold design analysis to an existing geometric modeler to provide designers, at the initial stage, with comprehensive process knowledge for gate synthesis. Performance analysis and feature-based geometric modeling.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.16 no.5
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• pp.113-118
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• 2017

In this paper, we propose a design procedure for determining the gate position robust to changes and inherent fluctuations in the process conditions during injection molding. To evaluate the robustness of the gate position, the signal-to-noise ratio is used, and noise conditions are implemented using orthogonal arrays, where the process variables are considered as noise factors and possible process fluctuations are set as the levels of the noise factors. To show the usefulness of the proposed robust design procedure, we apply it to a computer CPU baseplate. As a result, it is shown that a robust gate position can be determined that reduces the average warpage deflection by 2.4% and 1.7%, and the variance by 3.4% and 5.1%, compared to the two initial gate positions.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.316-321
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• 2000

Die Casting is one of the forming methods to manufacture large number of products with short period time and clean surface by high forming pressure and temperature of cast alloy. Die design is composed of selection of cast alloy, design of die casting product, runner and gate design etc. In reality, however, die design of die casting has been performed by trial and error method, which cause economic and time loss. This paper describes a research work of developing computer-aided design of die casting product and die design. Approach to the CAD system has been written in AutoLISP on the AutoCAD with personal computer. In this study, die design system for gate of die casting process has been developed to present algorithm for automation of die design, especially runner-gate system. As forming process and die design system using 3-D geometry handling are integrated with technology of process planning, die design is possible to set. In addition, specific rules and equations for the runner-gate system have been presented to avoid too many trails and errors with expensive equipment. It is possible for engineers to make automatic and efficient die design of die casting and it will result in reduction of expense and time to be required. An example is applied to cap-shaped casting using proposed algorithm.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.14 no.6
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• pp.125-131
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• 2005

The purpose of this study is an optimization of gate valve made by forging method instead of welding method. In this study, we propose an optimal shape design to improve the mechanical efficiency of gate valve. In order to optimize more efficiently and reliably, the meta-modeling technique has been developed to solve such a complex problems combined with the DACE (Design and Analysis of Computer Experiments). The DACE modeling, known as the one of Kriging interpolation, is introduced to obtain the surrogate approximation model of the function. Also, we prove reliability of the DACE model's application to gate valve by computer simulations using FEM(Finite Element Method).

• Journal of the Korean Society for Precision Engineering
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• v.18 no.3
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• pp.158-168
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• 2001

Die design of die casting is composed of selection of cast alloy, design of die casting product, runner design and gate design, etc. In reality, however, die design of die casting has been performed by trial and error method, which cause economic and financial loss. Nowadays, several FEM(finite element method) and FDM(finite difference method) codes have been developed to analyze process of die casting, but this is just confined to an offer of limited information for die design of die casting. In this study, die design system for gate of die casting process has been developed to present algorithm for automation of die design, especially runner-gate system. In addition, specific rules for runner-gate system have been presented to avoid too many trials and errors with expensive equipment. It is possible for engineers to make automatic and efficient die design of die casting and it will result in reduction of expense and time to be required.