• JSTS:Journal of Semiconductor Technology and Science
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• v.15 no.1
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• pp.114-121
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• 2015

In conventional LEDs, a mesa-structure is usually used and it causes the current to be overcrowded in a specific region. We propose a novel structure of GaN-based LED to overcome this problem. In order to distribute the current in an active region, a spreading pad is inserted at the p-type region in the GaN based LED device. The inserted spreading pad helps the current flow because it is more conductive than the p-type GaN layer. By performing electrical and optical simulations, the effects of the spreading pad insertion are confirmed. The results of electrical simulation show that the current spreads more uniformly and more radiative recombination is produced as well. Moreover, from the optical simulation, it is revealed that the ITO is less absorptive material than p-GaN if the condition of specific wavelength sources is satisfied. Considering all of the results, we can conclude that the luminescent power is enhanced by the spreading pad.

• Journal of the Korea Fashion and Costume Design Association
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• v.15 no.3
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• pp.41-50
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• 2013

This study aims to contribute to development of sanitary pad meeting customers' requirements by examining types, sorts, sizes and specifications of cloth sanitary pads currently sold in the market, and the results are as follows. First, with respect to materials of inside cloth of cloth sanitary pads, in most cases, 100% cotton knit was used as materials of the inside cloth and the pads were finished with knit cotton(including organic cotton) and woven cotton bias. Second, for the structures of the cloth sanitary pads, the Jacquard knits in the shape of beehive or waffle are mostly used. Third, the sizes of cloth sanitary pads were classified with 7 sorts were discovered that can be divided into liner, small-size, medium-size, large-size, overnight, extra overnight, accounting for the most percentage among cloth sanitary pads. Fourth, 11 sorts among cloth sanitary pads whose front and back shapes are the same were discovered, accounting for the most percentage. Fifth, cloth sanitary pads can be largely classified into a wing type, all-in-one type and insertion type, which includes subsidiary absorption layer. 9 sorts were wing types and all-in-one types, accounting for the most and percentage. Compared with the scope of the market for women's articles, there is no relevant study, so this study is expected to provide basic materials for women's articles and contribute to development of environment-friendly products as an alternative to a disposable sanitary pad which not only causes environment pollution but also has bad effects on women's health.

• Journal of the Korean Society of Costume
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• v.66 no.4
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• pp.45-60
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• 2016

Elderly women have a high risk of falling down in their daily lives. The purpose of this study is to develop protective pants for elderly women, which will mitigate the impact of falls, and play a major role in reducing injuries. The two types of design were proposed for development of protective pants by selecting pad insertion point and inserting lining for keeping pad in place through the checklist to investigate from the interviews with the medical workers and the investigation of the user requirement. Design A has protective pads in the hip, hip joint, and knee, while design B has protective pads in the hip and hip joint area. For the impact absorbing material, CR (chloroprene rubber) foam was selected for its flexibility, lightness, and impact absorbing capacity, and its pad shapes were designed to produce much flexibility in consideration of the activity and human body fitness of the wearers. Three kinds of pad types, which are the cut type, the porous type, and the honeycomb type, were proposed, and were manufactured to fit into the protective parts according to their design types.

• Journal of the Korea Fashion and Costume Design Association
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• v.19 no.3
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• pp.63-74
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• 2017

This study aims to contribute to the development of male incontinence underwear with an anti-aging effect that meets customer requirements by examining the types, sorts, sizes and specifications of male incontinence underwear currently sold on the market. The results of an analysis of a total of eight commercial products are as follows. 1) Among the samples, six types of incontinence underwear were of a pull-on style like regular underwear; two types were of a pad insertion style. With respect to the underwear design, four (50%) types of incontinence underwear were brief style. The rest were drawers (3, 37.5%). Only one was of a trunk (12.5%) style. 2) With respect to size, the percentage of Size 3 was 50%, followed by Size 4 (50%). Most of the size of the underwear uses hip measurement whereas Japanese products (3, 37.5 %) use waist circumference. 3) With respect to the materials of the incontinence underwear, natural fibers such as cotton were mostly used and a polyurethane or polyester was mixed to enhance the wearing sensation and stretchability of the underwear. Finally, for the structure of the pad area, a napping finish was the largest (3, 37.5%), single knit 2(25%), twill weave 2(25%), and rib weave 1.

• Journal of Applied Reliability
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• v.7 no.1
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• pp.23-29
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• 2007

Probe card is a test component which is to classify the known good die with electrical contact before the packaging in the ATE (automatic testing equipment). Conventional probe tip was mostly needle type, it has been difficult to meet with conventional type, because of decreasing chip size, pad to pad pitch and pads size increasingly. For that reason, probe cards using MEMS (micro electro mechanical system) technology have been developed for various semiconductor chips. In this paper, Area Array type MEMS Probe tip was designed,, fabricated, and characterized its mechanical and electrical properties. The authors found that good electrical characteristics under $1{\Omega}$ were acquired with gold (Au) and aluminium (Al) pad contact test over 0.5gf and 4gf respectively. And, contact resistance variation under $0.1{\Omega}$ were achieved with 100,000 times of repetition test. And, insertion loss (IS) for high frequency operation was ascertained over 300MHz at -3dB loss.

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.929-932
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• 2005

We report a pull-up type RF MEMS switch using double electrode without elastic deformation of the cantilever involved in the actuation. At a voltage of 4.5 V, reliable actuations are achieved such that the movable lower contact pad is pulled up by the electrostatic force to make contact with the upper pad. At a frequency of 50 GHz, an insertion loss of 0.7 dB and an isolation of 50.7 dB are obtained from the switch. The measured transient times for switch-on and switch-off are 120 and 80 us, respectively.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.1085-1090
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• 2007

In recent railway construction, the concrete slab track is getting highlighted as main stream in track type. However, it is the fact that there are different opinions in selection of the optimized spring coefficient of elastic pad. In this study, the performance of vibration reduction in different stiffness of rail pad for ballasted track was compared, and the changes in characteristics, such as static/dynamic deflection of components, vibration acceleration, insertion loss etc., were analysed by using ISI Program for various types of rail fastening system used in concrete slab track. It was concluded that the fastening system with softer pads has shown the better performance of vibration reduction in concrete slab track and the optimized static stiffness has been calculated to 21.1kN/mm for conventional railways, 17.6kN/mm for high-speed railways and 17.8kN/mm for subways.

• Tribology and Lubricants
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• v.38 no.5
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• pp.205-212
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• 2022

This paper presents experimental measurements of the structural characteristics of a two-pad beam-type gas foil journal bearing and its rotordynamic performance for a high-speed motor-driven turbocompressor. The test bearing had two top foils and two beam foils, each with an arc length of ~180°. Each beam foil was etched to obtain 40 beams with six geometries of different lengths and widths. The insertion of beam foils into the bearing housing produces equivalent beam heights. The structural tests of the bearing with a non-rotating journal revealed a smaller bearing clearance and larger structural stiffness for the load-on-pad configuration than for the load-between-pads configuration. Rotordynamic performance measurements during driving tests up to 100 krpm demonstrated synchronous vibrations and subsynchronous vibrations with large amplitudes. The test was repeated after inserting the shim between the top foil and beam foil to reduce the bearing radial clearance. The reduced bearing clearance resulted in a reduction in the peak amplitude of the synchronous vibrations and an increase in the speed at which the peak amplitude occurred. In addition, the onset speed and amplitude of the subsynchronous vibrations were dramatically increased and diminished, respectively. The rotor coast-down tests at 100 krpm show that the reduction in the bearing clearance extends the time to rotor stop, thus implying an improvement in hydrodynamic pressure generation and a reduction in bearing frictional torque.

• Journal of the Korea Fashion and Costume Design Association
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• v.18 no.1
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• pp.51-60
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• 2016

This study aims to contribute to development of women's incontinence panties with anti-aging effect meeting customers' requirements by examining types, sorts, sizes and specifications of women's incontinence panties currently sold in the market. The results of analysis of a total of 22 commercial products are as follows. 1. Among the samples, 21 incontinence panties were slip on type like regular underwear; only 1 was pad insertion type. With respect to the length of side seam, 17 (77.3%) incontinence panties were above 14 cm which is classified as maxi; the rest of them (5, 22.7%) were 7~11 cm which is classified as middy. 2. With respect to size, the percentage of Size 3 was 40.9% showing the largest, followed by Size 4 (31.8%), Size 2 (18.2%), Size 5 (9.1%). To produce the incontinence panties considering various ages and body shapes, it is recommended to select above Size 4 as a minimum. 3. With respect to materials of the incontinence panties, natural fibers such as cotton or rayon were mostly used and a polyurethane, nylon or polyester was mixed to enhance the wearing sensation and stretchability of the panties. Finally, for structure of the crotch area, single knit was the largest (9, 40.9%), terry weave 7 (31.8%), sofe pile weave 4 (18.2%), and waffle weave or diamond weave 2.