• Transactions of Materials Processing
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• v.9 no.6
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• pp.598-603
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• 2000

In order to improve trial-and-error based conventional practices for optimizing forming processes, a direct design method to guide iterative design practices, called the ideal forming theory, has been previously developed. In the theory, material elements are required to deform following the minimum Plastic work Path. The theory can be used to determine the ideal initial blank shape needed to best achieve a specified final shape while resulting in optimum strain distributions. In this work, the direct design method based on the ideal forming theory was applied to design initial design shape for VCR deck chassis. Based on the solution of the ideal forming theory, FEM analysis was utilized to evaluate an optimum blank shape to be formed without tearing. Simulation results are in good agreement with experimental data. It was shown that the proposed sequential design procedure based on direct design method and FEM can be successfully applied to optimize the die design Procedure of sheet metal forming processes.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2002.05a
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• pp.66-69
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• 2002

In the ideal forming theory(1), which has been deviously developed as a direct method for optimizing forming process, material elements are required to deform following the minimum plastic work path (or the proportional true strain path). Besides the general theory(2,3), specific ideal forming theories have been developed for membrane sheet forming(4) as well as two-dimensional steady bulk forming(5-7). In this work, the ideal forming theory was successfully applied for non-steady bulk forming under the plane strain condition. Here, the shape change complying with the minimum plastic work path, was effectively described by developing a numerical code based on the characteristic method. Numerical results obtained for a specific industrial part also include the optimum pre-forming shape and its evolving shape change to the final shape as well as the boundary traction history.

• Journal of Magnetics
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• v.18 no.4
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• pp.454-459
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• 2013

This paper deals with an optimal angle error reduction method of magnetic position sensor using hall effect elements. The angle detection simulation for the magnetic position sensor is performed by 3 dimensional finite element method and Taguchi method, one of the design of experiments. The magnetic position sensor is required to generate ideal sine and cosine waveforms from its hall effect elements according to rotation angle for precise angle information. However, the output signals are easy to include harmonics due to uneven magnetic field distribution from permanent magnet in the air-gap in the vicinity of hall effect elements. For the Taguchi method, three design parameters related to position of hall effect elements and shape of back yoke are selected. The characteristics of optimal magnetic position sensor are compared with those of original one in terms of simulation as well as experiment. Finally, the performances of the motor adopting original model and optimal model are represented for the purpose of verification of motor performance due to signals from magnetic position sensor.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.05a
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• pp.190-193
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• 2004

Ever since the ideal forming theory has been developed fur process design purposes, application has been limited to sheet forming and, for bulk forming, to two-dimensional steady flow. Here, application for the non-steady case was performed under the plane-strain condition based on the theory previously developed. In the ideal flow, material elements deform following the minimum plastic work path (or mostly proportional true strain path) so that the ideal plane-strain flow can be effectively described using the two-dimensional orthogonal convective coordinate system. Besides kinematics, for a prescribed final part shape, schemes to optimize a preform shape out of a class of initial configurations and also to define the evolution of shapes and boundary tractions were developed. Discussions include the two problematic issues on internal tractions and the non-monotonous straining. For demonstration purposes, numerical calculations were made for a bulk part under forging.

• Journal of the Korean Society of Costume
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• v.53 no.3
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• pp.137-154
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• 2003

The purpose of this study is firstly to survey the social and cultural background of 20th century and women's status, and to identify what the ideal body is like and what the elements of outer garment and underwear are and the techniques to incarnate the ideal beauty. Various papers are referenced for theoretical study and the elements and techniques of underwear are analyzed based on photographical materials. This paper concludes as follows. In 1910's, ideal beauty has changed to H-style. In other words, the outer garment has confined the lower part of the body with plain H-type Hobble silhouette to express plump bust, somewhat slim waist, and small hips, As the underwears, cylindrical corsets which fasten from under the bust down to lap, brassiere which are helpful for plump bust, and artificial busts were worn. In 1920's, outer garment were Straight box silhouette style which were cut as tubular without dart, and the underwears were corselets which have been tubular from the bust to hip and the tubular chemi-knickers. The former corsets which had been hard-boned and been fastened with strings have been replaced by the hook closure due to the development of elastic joining method. In 1930's, women pursued perfect body showing the line of bust, waist, and hip. In order to express elegant beauty of female of Slim and long silhouette, Doter and underwear have been cut with bias and gore, and soft and flexible materials were flowed along the body. World war II in 1940's has made the women as social. Ideal beauty has changed to Short straight box silhouette which no more shows body line. Outer and underwears were simple and Practical style. In 1950's, ideal beauty was well-matured, elegant Women which were represented by round shoulder, conical breast, tiny waist and round hip. Outer garment showed Hourglass silhouette representing the body-tight suits with round shoulder pad and the wide flare skirts. As the underwears, conical brassiere by top circular stitch were preferred for plump and bulged bust and tight corsets for tiny waist and magnificent petticoats were worn.

• Transactions of Materials Processing
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• v.13 no.6 s.70
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• pp.540-545
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• 2004

Ever since the ideal forming theory has been developed for process design purposes, application has been limited to sheet forming and, fur bulk forming, to two-dimensional steady flow. Here, application for the non-steady case was performed under the plane-strain condition based on the theory previously developed. In the ideal flow, material elements deform following the minimum plastic work path (or mostly proportional true strain path) so that the ideal plane-stram flow can be effectively described using the two-dimensional orthogonal convective coordinate system. Besides kinematics, fur a prescribed final part shape, schemes to optimize a preform shape out of a class of initial configurations and also to define the evolution of shapes and boundary tractions were developed. Discussions include the two problematic issues on internal tractions and the non-monotonous straining. For demonstration purposes, numerical calculations were made for a bulk part under forging.

• Fibers and Polymers
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• v.3 no.3
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• pp.120-127
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• 2002

Ever since the ideal forming theory has been developed for process design purposes, application has been limited to sheet forming and, for bulk forming, to two-dimensional steady flow. Here, application for the non-steady case was made under the plane-strain condition. In the ideal flow, material elements deform fellowing the minimum plastic work path (or mostly proportional true strain path) so that the ideal plane-strain flow can be effectively described using the two-dimensional orthogonal convective coordinate system. Besides kinematics, schemes to optimize preform shapes for a prescribed final part shape and also to define the evolution of shapes and frictionless boundary tractions were developed. Discussions include numerical calculations made for a real automotive part under forging.

• Journal of the Korea Safety Management & Science
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• v.18 no.2
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• pp.109-118
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• 2016

IPS(Ideal Production System) is a strategic cost management establishing ideal target cost, innovating cost structure and reduction. However, IPS was commonly used in assembly industry acquiring components and using them to assemble vehicles etc. Applying IPS to steel industry is a new try and not easy because cost elements in flow manufacturing are clustered and obfuscated in a complicated way. This paper proposes ICM (Ideal Cost Management) method adaptive to steel industry. One of the biggest advantages is that ICM could classify and categorize costs in detail according to accounts and manufacturing machines. Based on ICM information, steps of extracting and maximizing ideas are followed effectively. From 2013, ICM was applied successfully to POSCO Pohang Steel Works 38 factories.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39A no.1
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• pp.12-18
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• 2014

In this paper, a new peak-to-average power ratio (PAPR) reduction method for spatial modulation(SM) is presented. By using the matrix with all non-zero elements to precode the signals before transmitting, the transmit power is scattered over all transmit antennas for achieving the goal of PAPR reduction. If this matrix is also an unitary matrix, the distribution of transmit power over transmit antennas will be uniform and it also could retain the characteristic of avoiding inter channel interference (ICI) due to the orthogonality of unitary matrix. In case of a non-ideal amplifier, the proposed method can produce a considerable improvement that increases with a number of transmit antennas in performance. Furthermore, the new scheme achieves an identical performance with conventional one in the case of ideal amplifier.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.6
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• pp.2087-2103
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• 2014

What is an ideal authentication method for smartphone banking services? And what are the critical elements to be considered when designing it? To provide valuable insight for these questions, this study investigates various authentication requirements to be considered in smartphone banking service with the aspect of security, convenience and cost. By applying Analytic Network Process (ANP), this study first analyzes priorities among the requirements and then draws an ideal authentication method for smartphone banking service. Moreover, a sensitivity analysis has been conducted by varying the relative importance of several requirements. The results from the judgment of 72 experts revealed that, although Korean government has obliged the use of Public Key certificate, OPT and biometric alternatives may prove to be more appropriate for the smartphone banking service. These results will contribute to the provision of more secured and convenient smartphone banking services.