• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.11
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• pp.1871-1884
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• 1997

This paper describes the design process of a 3-component load cell with a multiple parallel plate structure which may be used to measure transverse forces and twisting moment simultaneously. Also we have derived equations to predict the bending strains on the surface of the beams in the multiple parallel plate structure under transverse force or twisting moment. It reveals that the bending strains calculated from the derived equations are in good agreement with the results from finite element analysis and experiment. Also we have evaluated the rated output and interference error of each component, which can be efficiently used to design a 3-component load cell with a multiple parallel plate structure.

• Polymer(Korea)
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• v.25 no.4
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• pp.594-601
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• 2001

Direct thermal lamination of polyethylene film on aluminum plate without using adhesive was tried by modifying their surfaces to have polar groups. Polyethylene film was modified by treating with oxygen or acrylic acid plasma. Aluminum plate was modified by treating with boiling water or diaminocyclohexane plasma. Fairly high adhesion strength was obtained even in the case when only the polyethylene film was modified, and adhesion strength was so high that film was broken during the adhesion test if both the film and the aluminum plate were modified. Even chemical bonding seemed to be possible when the film treated with acrylic acid was laminated on the plate treated with diaminocyclohexane plasma by forming amide linkage through the reaction between COOH groups on the film surface and NH$_2$ groups on the plate surface.

• Journal of Adhesion and Interface
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• v.4 no.3
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• pp.1-8
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• 2003

Adhesion between rubber compound and copper-film-coated steel plate (abbreviated hereafter as copper film plate) with different thicknesses of copper film was investigated. Two different methods were employed for the preparation of the copper film plates: a substitution plating of preelectroplated zinc with copper ion and a vacuum sputtering of copper on steel plate. Adhesion strength of the copper film plates with rubber compounds was largely dependent upon the thickness of copper film, regardless of their preparation methods. The copper film plates with thinner thickness than 75 nm showed high adhesion comparable to brass, while those with thicker copper film showed poor adhesion due to excessive growth of copper sulfide at adhesion interface.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.3
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• pp.189-196
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• 2008

The increase of system weight due to installation of cooling devices adds electrical and mechanical loads of humanoid robot, and in return, results in much heat. Therefore, the weight of cooling system is a critical issue for robot cooling. In this study, we propose non-metallic cold plates to deal with such problems. We compare thermal performances between one metallic cold plate and five different types of non-metallic cold plates. A metallic cold plate is totally made of copper. Five non-metallic PC(polycarbonate) cold plates, which are designed to reduce the overall weight of robot cooling system, are composed of a polycarbonate cover with different types of base plate. The overall heat transfer coefficients per unit mass and thermal resistances are obtained for the cold plates. The metallic cold plate shows the best thermal performance. It is interesting to note that the PC cold plate with an aluminum base plate with 18 channels shows the best overall heat transfer coefficient per unit mass. Most polycarbonate cold plates display fairly comparable thermal performance with more reduced system weight compared to the metallic cold plate.

• Journal of The Korean Astronomical Society
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• v.29 no.spc1
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• pp.401-402
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• 1996

• Proceedings of The Korean Cleft Lip And Palate Association
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• 2003.06a
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• pp.10-12
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• 2003

• Clinics in Shoulder and Elbow
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• v.17 no.4
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• pp.175-180
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• 2014

Background: For Neer type IIB fracture of distal clavicle with coracoclavicular ligament injury, various surgical treatments have been used in literatures. However, there was no consensus on the optimal treatment. The aim of this study is to report the clinical and radiological results of open reduction and internal fixation of unstable distal clavicle fracture and suture augmentation of disrupted coracoclavicular ligament. Methods: A prospective study was performed in 23 patients with Neer type IIB distal clavicle fracture in Seoul Medical Center, Eulji Hospital, and National Medical Center. Firstly, suture anchors are inserted in the base of coracoid process and preliminary reduction was achieved by tie-off of three suture limbs around the clavicle. Then, the final fixation was completed with anatomical locking plate. Bony union and the distance between coracoclavicular ligaments were evaluated. Clinical results and complications including stiffness and secondary procedures were evaluated. Results: Bony union was achieved in all cases except one (22 of 23). At mean 14.9 months, no significant difference in the mean coracoclavicular distance was observed compared to uninjured shoulder ($8.2{\pm}7.9mm$ versus $7.3{\pm}3.4mm$, p=0.14). Pain visual analogue scale, American Shoulder and Elbow Surgeons score, Constant score, and Disabilities of the Arm, Shoulder and Hand score were 0.5, 83.4, 78.5, and 6.2, respectively. Revision surgery was performed in one case of nonunion. Four patients who complained of skin irritation underwent implant removal. Conclusions: In cases of an unstable distal clavicle fracture with coracoclavicular ligament disruption, satisfactory clinical results were obtained by locking plate fixation and coracoclavicular ligament suture augmentation concurrently.

• Steel and Composite Structures
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• v.22 no.3
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• pp.691-712
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• 2016

In this editorial, buckling analytical investigation of the nanocomposite plate with square cut out reinforced by carbon nanotubes (CNTs) surrounded by Pasternak foundation is considered. The plate is presumed has square cut out in center and resting on Pasternak foundation. CNTs are used as amplifier in plate for diverse distribution, such as uniform distribution (UD) and three patterns of functionally graded (FG) distribution types of CNTs (FG-X, FG-A and FG-O). Moreover, the effective mechanical properties of nanocomposite plate are calculated from the rule of mixture. Domain decomposition method and orthogonal polynomials are applied in order to define the shape function of nanocomposite plate with square cut out. Finally, Rayleigh-Ritz energy method is used to obtain critical buckling load of system. A detailed parametric study is conducted to explicit the effects of the dimensions of plate, length of square cut out, different distribution of CNTs, elastic medium and volume fraction of CNTs. It is found from results that increase the dimensions of plate and length of square cut out have negative impact on buckling behavior of system but considering CNTs in plate has positive influence.

• Smart Structures and Systems
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• v.12 no.5
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• pp.547-577
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• 2013

To suppress vibration and noise of mechanical structures piezoelectric ceramics play an increasing role as effective, simple and light-weighted damping devices as they are suitable for sensing and actuating. Out of the various piezoelectric damping methods this paper compares mode based active control strategies to passive shunt damping for thin plates. Therefore, a new approach for the optimal placement of the piezoelectric sensors/actuators, or more general transducers, is proposed after intense theoretical investigations based on the Kirchhoff kinematical hypotheses of plates; in particular, modal and nilpotent transducers are discussed in detail. Based on the proposed distribution a discrete design for modal transducers is implemented, tested and verified on an experimental setup. For active control the modal sensors clearly identify the eigenmodes, whereas the modal actuators impose distributed eigenstrains in order to reduce the transverse plate vibrations. In contrast to the modal control, passive shunt damping works without requiring additional actuators or auxiliary power and can therefore act as an autonomous system, but it is less effective compensating the flexible vibrations. Exemplarily, an acryl glass plate disturbed by an arbitrary force initialized by a loudspeaker is investigated. Comparing the different methods their specific advantages are highlighted and a significant broadband reduction of the vibrations of up to -20dB is obtained.

• Proceedings of the SAREK Conference
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• 2004.06a
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• pp.139-139
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• 2004