• The Journal of Korean Academy of Prosthodontics
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• v.43 no.2
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• pp.176-190
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• 2005

Statement of problem. The current trend in prosthodontics is the adoption of a conservative approach to preparing dental prostheses by minimizing the amount of sound tooth structure removal during preparation. Purpose. The major disadvantage of the adhesion bridge is the inherently poor resistance to dislodgement that its use in areas subjected to high occlusal load is limited. The purpose of this study was to compare the dislodgement resistance of $Bio-pin^{(R)}$, conventional 3-unit and adhesion bridges. Material and methods. The experimental groups were classified as follows : Group I : 3-unit bridge cemented using $Super-Bond^{(R)}$ C&B Group II : Adhesion bridge cemented using $Super-Bond^{(R)}$ C&B Group III : $Bio-pin^{(R)}$ design adhesion bridge without incorporation of $Bio-pin^{(R)}$ (cemented using $Super-Bond^{(R)}$ C&B) Group IV-1 : $Bio-pin^{(R)}$ retained adhesion bridge incorporating a single $Bio-pin^{(R)}$ (cemented using $Super-Bond^{(R)}$ C&B) Group IV-2 : $Bio-pin^{(R)}$ retained adhesion bridge incorporating a single $Bio-pin^{(R)}$ (cemented using $Panavia^{(R)}$ F) Group V : $Bio-pin^{(R)}$ retained adhesion bridge incorporating two $Bio-pins^{(R)}$ (cemented using $Super-Bond^{(R)}$ C&B) Results. The results of this study were as follows : 1. Significant differences in dislodgement resistance of the restorations were found between Group I, Group II and Group III (p<0.05). No significant differences in dislodgement resistance of the restorations were observed between Group I Group IV-1 and Group V. However, there were significant differences in dislodgement resistance between Group II and the other groups (p<0.05). 2. No significant differences in dislodgement resistance of the restorations were observed between GroupIV-1 and GroupIV-2, both of which utilized a single $Bio-pin^{(R)}$. However, significant differences were observed when Group III was compared to either GroupIV-1 or Group V (p<0.05). 3. No significant differences in dislodgement resistance relative to the type of dental cements used were found. Conclusion. From the above results, it is concluded that the dislodgement resistance of $Bio-pin^{(R)}$ bridge restorations utilizing a single $Bio-pin^{(R)}$ is similar to that of a conventional 3-unit bridge. The results also suggest that $Bio-pin^{(R)}$ bridge restorations using a single $Bio-pin^{(R)}$ are a viable alternative to the conventional 3-unit bridge when minimal removal of sound tooth structure and fulfillment of both function and esthetic aspects are considered.

• Tribology and Lubricants
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• v.23 no.6
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• pp.306-311
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• 2007

This paper presents the friction characteristics of pb-fres pin bushing bearings for an automotive gasoline engine. The external load is 100 N to 600 N and the speed of the pin bushing bearing is 1000 rpm to 3000 rpm against the rubbing surfaces. And the contact modes of rubbing surfaces between a piston pin and a pb-free pin bushing specimen are a dry friction, an oil lubricated friction and a mixed friction that is starved by a lack of engine oil. Two influential factors of a contact rubbing modes and a material property are very important parameters on the tribological performance of a friction characteristic between a piston pin and a pb-free pin bushing. The experimental result shows that the pin bushing speed of 2000 rpm shows a typical oil film lubricated sliding contact mode in which means that as the applied load is increased, the friction loss is increasing. But other contact mode depending on the speed and the load may affect to the fiction coefficient without a regular and uniform trend. In summary, the oil lubricated rubbing surface definitely decreases a running-in period in short and increase oil film stiffness, and this may leads the reduction of a friction loss.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.45 no.11
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• pp.55-60
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• 2008

This paper proposed a dual-band RF switch using a Composite Right/Left Handed transmission line(CRLH TL) and PIN diode. RF switch is usually consist of $\lambda/4$ Right Handed transmission line(RH TL) and PIN diode. The dual band characteristics of RF switch was achieved by using CRLH transmission line instead of RH transmission line. CRLH Open-Stub was designed for resolve to reduction of isolation due to Package Inductance of PIN diode. The proposed RF switch was designed at GSM and DCS frequency-band. The measurement results showed a good agreement with theoretical result.

• Journal of IKEEE
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• v.13 no.4
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• pp.89-95
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• 2009

Recently, IC cards are used to protect personal information and to have user verification. Among them, the usage of Java Cards which can contain applications after issuing are increasing and installing several applets on Java card is possible. When Java Cards are used, applet works after completing user identification. In this paper, we designed, embodied and verified the mechanism of user identification process according to PIN setting of applets; Stored_PIN, Install_PIN and Update_PIN. These several applications of Java cards will be used for user identification independently or multiply, while using diverse user identification.

• Journal of the Korea Computer Industry Society
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• v.3 no.9
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• pp.1177-1188
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• 2002

To classify real time Lead pin images in this paper, The image acquisition system was composed to C.C.D, image frame grabber(DT3153), P.C(PentiumIII). I proposed image processing algorithms. This algorithms were composed to real time monitoring, Lead Pin image acquisition, image noise deletion, object area detection, point detection and pattern classification algorithm. The raw images were acquired from Lead pin images using the system. The result images were obtained from raw images by image processing algorithms. In implemental result, The right recognition was 97 of 100 acceptable products, 95 of 100 defective products. The recognition rate was 96% for total 200 Lead Pins.

• Korean Journal of Optics and Photonics
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• v.5 no.2
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• pp.333-339
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• 1994

We fabricated a single mode fiber pigtailed PIN-preamplifier front-end receiver module for the high speed optical receiver. Hybrid method was used to integrate GaInAs PIN photodiode and transimpedance type GaAs preamplifier. The capacitance and the diameter of light receiving area of PIN photodiode were 0.35 pF and $20{\mu}m$ respectively. The -3 dB cut-off frequency of PIN-preamplifier module was above 2 GHz, and the sensitivity of the module at 2.5 Gbps NRZ $(PRBS=2^{23}-1)$ signal was -25.2 dBm at $10^{-9}$ BER. > BER.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.19 no.5
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• pp.418-425
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• 2007

The power consumption and heat generation in a chip increase as the components are miniaturized and the computing speed becomes faster. Therefore, suitable heat dissipation has become one of the primary limiting factors to ensure the guaranteed performance and reliable operation of the electronic devices. A pin-fin array which may be considered as a porous medium could be used as an alterative cooling system of the electronic equipment. The aim of the present study is to investigate the forced-convective heat transfer characteristics of pin-fin heat exchangers. Convective heat transfer through the pin~fin array is analyzed experimentally based on porous medium approach. The influence of the structure of the pin-fin array including the pin-fin spacing, the pin diameter and plate length on heat transfer characteristic is investigated and compared with the Previous analytical results and existing correlation equations. Nowadays, electronic and mechanical devices become smaller and smaller. In this sense, the main purpose of this study is to decide the optimum pin-fin arrangement to get similar heat transfer performance when the length of the existing cooling system is reduced as a half.

• Proceedings of the Korea Information Processing Society Conference
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• 2008.11a
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• pp.1477-1480
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• 2008

주민번호대체수단은 주민번호를 대체하기 위한 본인확인정보로서, 5 개의 민간기업이 운영하는 민간 i-PIN과 행정안전부가 운영하는 공공 i-PIN이 서비스를 제공하고 있다. 하지만 주민번호대체수단이 더욱 활성화되기 위해서는 기존에 제시된 보안성, 편의성 문제를 해결해야 한다. 본 논문은 신원 선택기를 추가하여, i-PIN의 프로토콜을 변경하지 않는 범위 이내에서 i-PIN의 단점으로 지적되는 로그인 번거로움, i-PIN 사이트 기억 문제, 피싱을 비롯한 보안 문제를 해결하는 방안을 제시하였다. 제안하는 방법은 사용자가 가입한 i-PIN 제공자에 접근하는 단계, i-PIN 제공자에 id 와 비밀번호를 입력하는 단계를 없애고, 신원 선택기를 통해 사용할 신원 정보를 선택하는 것만으로 처리되도록 하였다. 본 기술은 ETRI 에서 개발중인 전자 ID 지갑 솔루션을 통해 구현되었으며, 해당 서비스는 2009 년 중에 민간 i-PIN 제공자를 통해 시범 도입될 예정이다.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.1
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• pp.77-83
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• 2010

Radiation characteristics of $5{\times}4$ pin array patch antennas are compared to those of $5{\times}2$ pin array patch antennas for several substrate thicknesses using the computer simulation. Since the number of unit cells of a $5{\times}2$ pin array patch antenna is half of that of a $5{\times}4$ pin array patch antenna, the number of pins used in a $5{\times}2$ pin array patch antenna is half of that in a $5{\times}4$ pin array patch antenna and the patch width of a $5{\times}2$ pin array patch antenna is very small compared to that of a $5{\times}4$ pin array patch antenna. However, the radiation characteristics of a $5{\times}2$ pin array patch antenna are almost similar to those of a $5{\times}4$ pin array patch antenna.

• Tribology and Lubricants
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• v.36 no.3
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• pp.168-192
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• 2020

In recently designed diesel engines, the running conditions for piston-pin bearings have become severe because of the higher combustion pressure and increased temperature. Moreover, the metal removal from the bushing material has strongly reduced the ability of the antifriction material to accept asperity contacts. Therefore, it is necessary to find ways of reducing wear scar on the connecting-rod small-end bushing and piston-pin boss bearing related to the higher combustion pressure on the power cell of an engine. In this work, the position and level of material removal from the surfaces of the bushing and bearing under such severe operating conditions - for example, maximum power and torque conditions of a passenger car diesel engine - are estimated for several combinations of surface roughness. First, piston-pin rotating motion is investigated by calculating the friction coefficient at piston-pin bearings, the oil film thickness, and the frictional torques induced by hydrodynamic shear stress. Subsequently, the wear scarring on the surfaces of a connecting-rod small-end bushing and two piston-pin boss bearings related to piston-pin rotational motion is numerically calculated under the maximum power and torque operating conditions. This work is helpful to determine the reasonable surface roughness of the bushing and bearing for reducing wear volume occurring at the interface between a bearing and a shaft.