• Imaging Science in Dentistry
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• v.48 no.2
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• pp.87-96
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• 2018

Purpose: The present study aimed to evaluate which of the following imaging methods best assessed misfit at the tooth-restoration interface: (1) bitewing radiographs, both conventional and digital, performed using a photostimulable phosphor plate (PSP) and a charge-coupled device (CCD) system; (2) panoramic radiographs, both conventional and digital; and (3) cone-beam computed tomography (CBCT). Materials and Methods: Forty healthy human molars with class I cavities were selected and divided into 4 groups according to the restoration that was applied: composite resin, composite resin with liner material to simulate misfit, dental amalgam, and dental amalgam with liner material to simulate misfit. Radiography and tomography were performed using the various imaging methods, and the resulting images were analyzed by 2 calibrated radiologists. The true presence or absence of misfit corresponding to an area of radiolucency in regions subjacent to the esthetic and metal restorations was validated with microscopy. The data were analyzed using a receiver operating characteristic (ROC) curve, and the scores were compared using the Cohen kappa coefficient. Results: For bitewing images, the digital systems (CCD and PSP) showed a higher area under the ROC curve (AUROC) for the evaluation of resin restorations, while the conventional images exhibited a larger AUROC for the evaluation of amalgam restorations. Conventional and digital panoramic radiographs did not yield good results for the evaluation of resin and amalgam restorations (P<.05). CBCT images exhibited good results for resin restorations(P>.05), but showed no discriminatory ability for amalgam restorations(P<.05). Conclusion: Bitewing radiographs (conventional or digital) should be the method of choice when assessing dental restoration misfit.

• Journal of Digital Convergence
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• v.6 no.2
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• pp.87-95
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• 2008

Information technology is rapidly diffused throughout the world. Unfortunately, as the technology goes on the disabled vocational rehabilitation is more isolated in physically and mentally. A new paradigm, 'Digital practical use Opportunity' is a product of the tremendous technological changes driving the disabled vocational rehabilitation. The employment for the disabled vocational rehabilitation is a hot issue. Because lack of education rehabilitation cause many problems for the employer. Relating program of employment and education for the disabled vocational rehabilitation, they can get a job in a better condition. This study propose a model of good environmental employment for the disabled vocational providing them the way of getting a job so that they can go as a member of highly developed society. It conducted in society could fundamentally advance our knowledge about the structure of the employment of the disabled vocational rehabilitation, cure their feelings, give them a chance to live happier, stronger, healthier.

• Journal of information and communication convergence engineering
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• v.8 no.1
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• pp.103-106
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• 2010

In this paper, the delay times were evaluated to develop highly reliable time-to-digital converter(TDC) in analog and digital delay element structures. The delay element can be designed by using current source or inverter. In case of using inverter, the number of inverter has to be controlled to adjust the delay time. And in case of using current source, the current for charging and discharging is controlled. When the current source is used the delay time of the delay element is not sensitive with varying the channel width of CMOS. However, when the inverter is used the delay time is directly related to the channel width of CMOS. Therefore to obtain good reliability in TDC circuit the delay element using current source is more stable compared to inverter in the viewpoint of the variation of fabrication process.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.19 no.4
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• pp.18-23
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• 2011

Generally, the digital circuit card can be tested by automatic test equipment using LASAR(Logic Automated Stimulus and Response). This paper proposes the ROM data extracting algorithm which can test the digital circuit card that consists usually ROMs. We are implemented of the proposed fault detecting program by LabWindow/CVI 8.5 and the digital automatic test instrument with NI-VXI(National Instrument - Versa Bus Modular Europe eXtentions for Instrumentation) card. We also make an interface circuit board connecting the digital test instrument and the digital circuit card. It shows the good performance of getting the data from ROMs.

• Journal of Institute of Control, Robotics and Systems
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• v.15 no.8
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• pp.786-791
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• 2009

Recently, digital camera module has been extensively utilized in mobile devices. The digital camera module should be smaller and lighter than digital still camera module to be used in mobile device. But, mobile camera can't get high quality image as good as the one of digital still camera due to the optical limitation of minimized module. Especially, AE system of mobile camera occurs excessive hunting and oscillation due to miniaturization of module. In this paper, improved AE algorithm which is applied fuzzy PI control is suggested to compensate this point.

• Proceedings of the Korean Society of Computer Information Conference
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• 2013.07a
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• pp.35-37
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• 2013

UCI is contributing to establishing and administrating CMS to improve the quality of contents efficiently and effectively. In these days, enterprises are also making a new try to manage copyrights of digital contents by use of DRM(Digital Right Management). UCI would be a good solution to solve this overburden. The objective of our research is to study on practical uses of various digital contents models on the basis of UCI. We introduce two business cases; one is publishment of digital contents and the other is DB service of digital contents.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.1158-1161
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• 2006

The toner type paper-like display (PLD) has been developed with two polymer particles having opposite polarity which is composed of polymer, colorant and external additives (nano-sized silica). Nano-sized silica with triboelectric charge was used for the charge control agent (CCA) and influenced on the electrostatic properties of the silica-coated polymer particles. The PLD cell using silica-coated particles (200 seconds) had shown a good white appearance and low driving voltage. The result could be explained in terms of the surface morphology and the cohesiveness depending on the silica coating time.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2003.04a
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• pp.321-326
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• 2003

The subjects of this study are to examine and to apply the methods of making 1:5,000 scale maps using 1m resolution stereo images of IKONOS for the Munsan area of Paju-city where aerial photo surveying cannot possible because of security conditions. GCP(Ground Control Point) were acquired from GPS surveying and were to perform geometric corrections on images. Digital Map used IKONOS stereo images and it worked from the digital analytical stereoplotter. From field investigation, RMSE errors of the plane and vertical positions are estimated to 1.706m and 1.231m, respectively. The plane accuracy is better than an accuracy required by NGIS (national GIS) programs. Local information from field investigation was added and the resulting maps should be good as digital map under the scale of 1/5,000.

• Journal of Information Display
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• v.8 no.1
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• pp.14-17
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• 2007

The toner type paper-like display (PLD) has been developed with two polymer particles having opposite polarity composed of polymer, colorant and external additives (nano-sized silica). Nano-sized silica with triboelectric charge was used for the charge control agent (CCA) and influenced on the electrostatic properties of the silica-coated polymer particles. The surface morphology and the cohesiveness of silica-coated polymer particles were changed with the silica coating time. From these results, it was verified that the PLD cell using silica-coated particles (200 seconds) shows a good white appearance and low driving voltage.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.8 no.1
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• pp.65-75
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• 1996

A pilot plant, which is simplified the hot water heating control system of a large scale residential building, is used to investigate the effects of control methods and operating conditions on the system performance and to compare control characteristics. Digital variable structure controller(DVSC) and digital PI controller are implemented to control the speed of the circulating pump for the pilot plant using PC. For the DVSC, a control algorithm is suggested, which using a nonlinear sliding surface and a PID sliding surface outside and inside of output error boundary layer, respectively. Smith predictor algorithm is used for the compensation of long dead time. The suggested DVSC yields improved control performance compared with existing DVSC using linear sliding surface only. the system responses with the suggested DVSC shows good responses without overshoot for various operating conditions and robust under external disturbances compared with digital PI controller.