• Design & Manufacturing
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• v.11 no.3
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• pp.19-24
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• 2017

In these days, increase requirement of TEM (Transmission Electro Microscope) in not only scientific field but also industrial field. Because TEM can measure inner-structure of specimen a variety of materials like metal, bio. etc. When use TEM, specimen should be thin about 50nm. So making for thin specimen, use Ion milling device that include specimen holder. The holder generally made of Aluminium Aluminium holder is worn away easily. For this reason, using time of ion milling with aluminum holder is too short. To solve the problem, we replace aluminium holer to molybdenum alloy holder. In this paper, we design molybdenum alloy holer for CAM and modify CAD modeling for effective machining process. So we array a specimen 3 by 4 and setup orientation for one-shot machining process. Next we make a CAM program for machining. we making a decision two machining strategy that chose condition of tool-path method, step-down, step-over. etc. And then conduct machining using CNC milling machining center. To make clear difference between case.1 and case.2, we fixed machining conditions like feed-rate, main spindle rpm, etc. After machining, we confirm the condition of workpiece and analysis the problems case by case. Finally, case.2 work piece that superior than case.1 cutting with WEDM because that method can not ant mechanical effect on workpiece.

• Journal of the Korean Society for Precision Engineering
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• v.7 no.3
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• pp.56-65
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• 1990

This paper describes a computer aided tool design system of deep drawing of cylindrical cups with or without flange by press. An approach to system is based on knowledge based system. The computer program has written in basic language with personal computer Knowledges for tool design are formulated from the plasticity theory, handbooks, experimental results and empirical knowhow of the field experts. The capabilities of developed system include 1) the selection of tool structure (with or without blank holder, single or double action, lift up or draw off type), 2) the design of tool elements(punch/holder, die/holder etc.) for the previous selected tool structure by the process planning output and the production quantity. The final output is generated in graphics form for design sheet.

• The Korean Journal of Applied Statistics
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• v.22 no.1
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• pp.59-73
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• 2009

A floating-strike lookback call option gives the holder the right to buy at the lowest price of the underlying asset. Similarly, a floating-strike lookback put option gives the holder the right to sell at the highest price. This paper will propose an outside floating-strike lookback call (or put) option that gives the holder the right to buy (or sell) one underlying asset at some percentage of the lowest (or highest) price of the other underlying asset. In addition, this paper will derive explicit pricing formulas for these outside floating-strike lookback options. Sections 3 and 4 assume that the underlying assets pay no dividends. In contrast, Section 5 will derive explicit pricing formulas for these options when their underlying assets pay dividends continuously at a rate proportional to their prices. Some numerical examples will be discussed.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.788-791
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• 2004

This paper presents a general description of single and dual contact tooling systems, finite element analysis, and discussions on the application of the system to the 5-head router machine which is in particular for aerospace components. This study has been performed as part of the development of the new generation 5-head router machine which is designed for high productivity. Such high productivity in essence requires high speed rotation and multiple spindles in one machine. The high speed rotation may exceed a range in a conventional single contact tooling system. The conventional tooling system is reevaluated in comparison with the dual-contact system. Finite element analysis using simplified spindle models compares major differences in the two systems. Some problems in the application to the 5-head router machine are discussed.

• Proceedings of the KSR Conference
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• 2004.06a
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• pp.903-908
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• 2004

Among welded structure bogies in use for high speed freight car, a part of bogies manufactured in 1999 and 2000 have found problems that crack occurs in its end beam. In case of a freight car the difference of weight between empty and loading conditions are worse than in case of a passenger car. Moreover its brake system is tread brake without second suspension system. Cracks of end beam is supposed to be due to loading by brake system rather than vertical loading by freight. These cracks can make brake system useless and may be a cause of derailment in the worst case. In this study, we have proposed a simple torsion-free brake shoe holder hanger to remove torsion of hanger bracket which was supposed to be one of causes of cracks and performed finite element analyses. Also static load test was applied in torsion free brake shoe holder.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2007.06a
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• pp.139-143
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• 2007

The need for technological developments of lithography equipment is urgent for the stable production in response to the rapid growth of the recent display industry. As an example, the products currently in the market face alteration problems resulting from excessive weight of the mask holder part. This is one of obstacle for the automation of the equipment. In response, the mask holder part problem has been minimized through FEM and design of experiments in order to optimize the situation with minimized Deflection and reduced mass for satisfactory replacement of the mask holder part.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.04a
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• pp.144-149
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• 2008

In this paper, vibration sources of a car-holder are identified and the car vibrations are reduced by structural modification. For vibration identification, vibration signals are measured by an accelerometer when the car is moving. From some experiments and finite element analyses, it is also found that resonances occur because the natural frequencies of the car exist in usual driving speed range. To shift the natural frequencies outside the driving speed range, the connection part is modified to increase stiffness. It is verified that considerable amount of vibration are reduced by the structural modification.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.7
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• pp.885-894
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• 2001

A large eddy simulation(LES) is performed for turbulent flow in a combustion device. The combustion device is simplified as a cylinder with sudden expansion. To promote turbulent mixing and to accommodate flame stability, a flame holder is attached inside the combustion chamber. Emphasis is placed on the flow details with different geometries of the flame holder. The subgrid scale models are applied and validated. The simulation code is constructed by using a general coordinate system based on the physical contravariant velocity components. The calculated Reynolds numbers are 5000 and 50000 based on the bulk velocity and the diameter of inlet pipe. The predicted turbulent statistics are evaluated by comparing with the LDV measurement data. The agreement of LES with the experimental data is shown to be satisfactory.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.05a
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• pp.712-717
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• 2001

In order to modify flexible mode frequencies, finite element analysis is applied for a lens-holder in pick-up actuator. Several design parameters like shape and local dimension of a lens-holder were selected adequately and sensitivities of the design variables for vibration modes were obtained by FE analysis and this result was used for updating FE model. A sensitivity matrix between the natural frequencies and the design variables was calculated by finite difference method. By comparing the calculated natural frequencies with target frequencies, modification of the design variables was acquired and used for improving FE model. Calculated natural frequencies after several iterations by FE analysis coincided with target frequencies and the errors between them were minimized.

• Journal of Distribution Science
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• v.13 no.10
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• pp.15-21
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• 2015

Purpose - This study examines a bundling effect on production and distribution in a patent-protected industry. Despite the heavy use of bundling strategies in the information and technology industry, literature has paid scant attention to bundling of intellectual property rights. This study examines a theoretical exploration of the bundling effect on licensing behavior. Research design, data, and methodology - To address this behavior, we build a simplified model consisting of three stages: 1) bundling decision, 2) licensing agreement, and 3) competition. The subgame perfect Nash equilibrium is applied to the model. Results - A single-patent holder with superior technology grants its own license to the multiple-patent firm, thereby leaving the market. Anticipating the single right holder's licensing strategy, the multiple-patent firm offers a bundle, making the single-right holder's bargaining position weaker. Conclusions - Bundling is an effective business strategy, resulting in multiple products for a firm as it faces other firms with single-product lines in each market. Taking advantage of the multi-patent or multi-product lines, the firm utilizes the bundling strategy obtaining better technology from the standalone single-patent firms.