• Journal of Powder Materials
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• v.15 no.3
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• pp.204-209
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• 2008

Aluminum alloys are not only lightweight materials, but also have excellent thermal conductivity, electrical conductivity and workability, hence, they are widely used in industry. It is important to control and enhance the densification behavior of metal powders of aluminum. Investigation on the extrusion processing combined with equal channel angular pressing for densification of aluminum powders was performed in order to develop a continuous production process. The continuous processing achieved high effective strain and full relative density at $200^{\circ}C$. Optimum processing conditions were suggested for good mechanical properties. The results of this simulation helped to understand the distribution of relative density and effective strain.

• Journal of Powder Materials
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• v.3 no.4
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• pp.253-259
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• 1996

The efficiency of thermoelectric devices for different applications is known to depend on the thermoelectric effectiveness of the material which tends to grow with the increase of its chemical homogeneity. Thus an important goal for thermal devices is to obtain chemically homogeneous solid solutions. In this work, the new process with rapid solidification (melt spinning method) followed by hot pressing was investigated to produce homogeneous material. Characteristics of the material were examined with HRD, SEM, EPMA-line scan and bending test. Property variations of the materials were investigated as a function of variables, such as dopant ${CdCl}_{2}$ quantity and hot pressing temperature. Quenched ribbons are very brittle and consist of homogeneous $Bi_2Te_3$, ${Bi}_{2}{Se}_{3}$ solid solutions. When the process parameters were optimized, the maximum figure of merit was 2.038$\times$$10^{-3}K^{-4}. The bending strength of the material hot pressed at 50$0^{\circ}C$ was 8.2 kgf/${mm}^2$.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1113-1116
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• 2003

In this paper, it is suggested that the technology sound measurement which is to search the inferiority of the plate during the pressing. We evaluate whether there is a inferiority by analysing and comparing the satisfactory and inferior plate with the method of a spectrum analysis by measuring the sound which is emitted during pressing. We designed the analysis algorithm to detect inferior plate throughout comparison of measured sound data using FFT, DFT and DASYLab S/W. In addition to these, we suggest the way to compare both inferior and satisfactory signal statistically.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.4
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• pp.687-692
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• 1998

To use onion(Allium cepa L.) residue as raw materials of food product, yields of onion-juice according to various extracting methods and optimal extracting condition of quercetin and its related glycosides were carried out. Onion juices gained by the methods of pressing, rotary crushing, freeze pressing and enzyme treatment. The yield by the method of enzyme treatment was higher than others. The yields of juice from fresh onion and heat-treated onion(8$0^{\circ}C$/10min) by pressing were 66% and 83%, respectively. Ethanol extraction of onion was efficient at 75$^{\circ}C$ and acetic acid extraction was proper at 3% concentration for 3 hours at 11$0^{\circ}C$. The onion extract was fractionated in the order of hexane, chloroform, ethylacetate and butanol to test flavonoids. The highest abundant flavonoids were found in ethylacetate and butanol fraction.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1996.06a
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• pp.516-518
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• 1996

Bimuth telluride type thermoelectrics are prepared by AC current applied got pressing method. It is possible to minimize the defects arising from the vaporization of Te, because of the very short processing time. The optimum conditions for the got pressing of 95mol% $Bi_2Te_3$-5mol%$Bi_2Se_3$ themoelectrics are sintered at $400^{\circ}C$, for 2min. with 1500 kgf/$cm^2$ from the particle size of 125 to 250 $\mu$m rang of powder. the resulted Z value (figure of merit) was 2.2$\times$10-3deg-1.

• The Journal of the Society of Korean Medicine Diagnostics
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• v.25 no.1
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• pp.72-87
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• 2021

Objectives This is the review on the Jeolgyeong which means diagnosis method of meridian and acupoints. Detecting method of meridian and acupoints under the disease condition using fingertips were more developed in Japan than in China and Korea. This study is the introduction to the Japanese style palpation method on meridian and acupoints. Methods Firstly the textbook 'Acupuncture medicine' published by the committee of Korean professors' association of acupuncture and moxibustion was analyzed. Especially the contents of the palpation method on meridian and acupoints were focused and summarized and secondly the book describing the palpation method on meridian and acupoints was selected, translated and summarized. Results Until now the knowledge on the acupoints reaction depending on the patient's status, the deficiency pattern and the excessive pattern was rarely described in China and Korea. On the contrary, 4 kinds of reactions in the deficiency pattern and 4 kinds of reactions in the excessive pattern were well described in Japanese literatures. Mild touching, mild pinching, rubbing, mild pressing and severe pressing were also described along the meridians. Except the bladder meridian Back Shu points, Yuan points, Luo points, Xi(cleft) points, Front Mu points were depicted as the same as those in China and Korea. For the bladder meridian lines, 4 lines were organized including 2 lines of Hua-Tuo-Jia-Ji-Xue and the middle line between 1st and 2nd bladder meridian line as well as 1st bladder meridian line and 2nd bladder meridian line. Conclusions Detecting meridians or acupoints and using them for diagnosis and treatment is a method used in China, Korea, and Japan. However, detailed descriptions of the method for detecting meridians through palpation are revealed in Japanese books. Palpation methods for diagnosing meridians using touching, pinching, rubbing, and pressing methods are expected to be standardized and systematically learned in Korea.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.7
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• pp.3142-3150
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• 2013

Present research deals with an optimal design of the C-type frame of a desktop pressing machine to minimize its deformation which plays an important role in accuracy of the machine. Deformation pattern of the frame is analyzed by the finite element method. Design parameters are defined for the frame to derive an optimal design. Displacement and weight sensitivities of the parameters are analyzed using the method of the parametric study. On the basis of the response curves for the parameters, optimal designs of the frame are proposed. Effectiveness of the optimal design is verified by analyses in the viewpoint of the deformation and weight of the frame. Deformation of the optimized frame without increase of the weight is 87.5 % of the original frame.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.6
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• pp.182-187
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• 2001

Much research efforts have been made on the equal-channel angular pressing(ECAP)that produces ultra-fine grain size materials. Recently many materials have been tested for ECAP process, and in this paper pure-Zirconium is considered due to its applicability to nuclear reactors. Among many process parameters of ECAP, frictional effects on the deformation behavior of materials and on the stress distribution of die have been investigated. The finite element method has been employed in order to investigate this issue, and experiments have also been made to verify the numerical results.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1975-1979
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• 2005

Equal channel angular pressing has been employed to produce materials with ultra-fine grains that have high strength and high corrosion resistance properties. Along with the experiments, the finite element method has been widely performed to investigate the deformation behavior of specimen and the effects of process parameters of ECAP. In general, several steps of ECAP have been repeatedly executed. In this paper, the effects of sectional shape change have been investigated during ECMAP (RouteA, RouteC) with pure-Zr by using three-dimensional finite element analysis. The results have been compared with the experimental results.

• Design & Manufacturing
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• v.11 no.1
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• pp.19-25
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• 2017

A conventional taped banknotes detecting device in the banknote counting machine have some problems caused by temperature, humidity, dust and other environmental conditions. In order to the improve the detection performance of taped banknote in the banknote counting machine, we developed taped banknotes detecting device that the ultrasonic wave sensor was replaced by mechanical method device. There are many factors for the performance of the taped banknote detecting device of a mechanical method, we considered three main factors that are the amplification ratio of the thickness of banknotes, the pressing force of banknotes and the feeding speed of banknotes. We carried out the experiments with the 27 kinds of combination of these three main factors. As the result, accurate detection was possible to the normal banknotes and taped banknotes regardless of the feeding rate in terms of the amplification rate 27 times and the pressing force 660gf.