• 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.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.1
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• pp.12-20
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• 2009

In this paper, we introduced the large signal model of a PIN diode and presented the measurement methods for each parameter of the large signal model. The elements of the PIN diode model are classified into the elements with a constant value and the elements depending on the junction voltage. We implemented the constant elements by lumped elements and the voltage-dependent elements by a SDD in ADS. The developed large signal model was successfully worked with various circuit simulations, such as simple DC, AC, S-parameter, Transient, and HB simulations. In order to verify the developed large signal model, we compared that the measured results of a limiter and a attenuator with the simulated results using the PIN diode model, which are in good agreement.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.27 no.2
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• pp.156-162
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• 2016

This paper proposes a novel orthogonally-polarized dual-band switchable microstrip antenna. The proposed antenna consists of a perpendicular feeding network and an radiator with a PIN-installed H-shaped slot. When the states of one single PIN diode in H-slot are controlled by bias voltages, the controlled physical geometry of the H-slot determines the operation frequencies of switchable 1.80 GHz and 2.43 GHz for vertically polarized linear polarization and fixed 2.06 GHz for horizontally linear polarization. The implemented antenna experimentally demonstrates reconfigurable dual-band capability by means of controling the states of the PIN diode. The simulation and measurement results of the implemented antenna have been in good agreement with the reflection coefficients, realized antenna gains and far-field radiation patterns at each of the PIN diode states.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.17 no.2
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• pp.145-185
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• 2007

A resident registration number is used to confirm and prove his/her identity in a government/non-governmental agency. It is a essential requirement to become the registered member on internet website in Korea. It is serious problem that the resident registration number and name are outflowed in internet and misused by others. So the MIC(Ministry of Information and Communication) in Korea plans and operates the identification system using I-PIN that integrate 5 alternative methods of resident registration number. In this paper, we analyze the problem about the method of 5 I-PIN services and show the security analysis on the implementation vulnerabilities of I-PIN services. we also analyze 17 websites that provides identification system using I-PIN. Finally, we analyze the overall problem of I-PIN service and propose the countermeasure about the problem.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.22 no.8
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• pp.736-741
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• 2012

Squeak noise is studied by using the pin-on-disk system with aluminum pin and steel disk. Noise induced by friction is measured with respect to the normal loads and sliding speeds. The negative slope of friction-velocity curve is seen when the squeak noise occurs. It is found that the normal load influences on the sound level of squeak noise. From the hammering test, the major frequency of the squeak noise is shown to correspond to one of system modes, which implies that squeak phenomenon arises from the unstable system modes. The result of FE analysis shows that the major squeak mode is the bending mode of the pin.

• Tribology and Lubricants
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• v.21 no.1
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• pp.39-45
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• 2005

Investigation of the mass effect on the journal traces in the clearance of engine bearing has been performed for better design of mass distribution of crank system components such as crank pin, piston, con-rod, balance weight, crank throw weight, etc. as well as for better oil reaction behaviors to the applied forces from the cylinder pressures on the bearing. In this preliminary study, crank pin traces in the engine bearing clearance are computed by varying the equivalent magnitude of crank pin mass that includes the masses of crank pin, piston, con-rod. etc.. while most previous studies regarding journal traces in the bearing clearance neglect the inertia effects of crank pin mass. Although the inertia effect of pill mass is negligibly small compared to viscous force by ${\pi}bearing$ theory, it is found that it gives a great amount of influences on the journal traces in full bearing computation $(2\pi\;bearing\;theory)$ under the dynamic loading conditions.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1994.10a
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• pp.543-548
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• 1994

This is the paper on the development of assemnly automation and visual inspection system for smart card reader connector. The automation consists of 3 main process injection, assembly and inspection. During the injection, the main pin of a reel. transferred under uniform tension, is cut with an injection interval and positioned precisely to an injection mold by roll feeder after injection. The main base is stacked to a magazine for main pin's exact positionning to a mold . For last effective production, The turn table and pick & place are driver with gears and came by a single monter. We developed the small parts handling technigue for stable supply of micro ist pin and 2nd pin and could determine the orientation and position of those pins. For reliable inspection, We used the vision system which examins the guality of arranged pins with a CCD camera. The connector models which can be manufactured with this system are 8 pin and 10 pin type. The user can select the connector model for production and adjust the torerable error range during the inspection of arranged pins.

• Textile Coloration and Finishing
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• v.16 no.3
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• pp.39-46
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• 2004

This study surveys the physical properties of DTY composite yarns manufactured by pin, disk and belt texturing systems. For this purpose, 208d/36f POY PET and 40d/12f high shrinkable PET filaments are prepared for specimens. The composite yarns are manufactured with this texturized POY and high shrinkable PET filament using the pin, disk and belt type texturing machines. While the processing conditions of the pin and disk types texturing machines were fixed, those of a belt type texturing machine were varied with over feed to compare and analyze with the yarn physical properties of pin and disk type composite yarns.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.8
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• pp.487-494
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• 2000

This paper describes the design, fabrication and experiments of surface-micromachined aluminum micromirror array with hidden pin-joints. Instead of the conventional elastic spring components as connection between mirror plate and supporting structure, we used pin-joint composed of pin and staples to support the mirror plate. The placement of pin-joint under the mirror plate makes large active surface area possible. These flexureless micromirrors are driven by electrostatic force. As the mirror plate has discrete deflection angles, the device can be ap;lied to adaptive optics and digitally-operating optical applications. Four-level metal structural layers and semi-cured photoresist sacrificial layers were used in the fabrication process and sacrificial layers were removed by oxygen plasma ashing. Static characteristics of fabricated samples were measured and compared with modeling results.

• Journal of Korea Society of Digital Industry and Information Management
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• v.4 no.3
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• pp.45-53
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• 2008

As internet is wide spread, the number of internet service provider is increased. Internet service providers gather the personnel information with inhabitants registration identification number for the user management and the adult authentication. The personnel information is spreaded thorough the Internet by the system hacking, mismanagement and malicious resale. And the personnel information is used for spam email, phishing scams, etc. by malicious others. So the Ministry of Information and Communication Republic of Korea developments I-PIN system of the personnel identification. But, I-PIN has some problem the guideline for it and the method of 5 I-PIN services. In this paper, we analyze the problem about the guideline for I-PIN and the method of 5 I-PIN services. And we propose the countermeasure about the problem.