• 산업공학
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• 제12권2호
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• pp.205-209
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• 1999

In reverse engineering area, the reconstruction of surfaces from scanned or digitized data is being developed, but geometric model of existing objects is not available in industries. This paper presents the new approach to the reconstruction of surface technique. A proposed methodology finds base geometry and blends surface between them. Each based geometry is divided by tri-angular patches which are compared with their normal vector for face grouping. Each group is categorized analytical surface such as a part of cylinder, sphere and cone, and plane shapes to represent the based geometry surface. And then, each based geometry surface is implemented to the infinitive surface. Infinitive surface's intersections are trimmed by boundary representation model reconstruction. This method has several benefits such as time efficiency and automatic functional modeling system in reverse engineering. Especially, it can be directly applied 3D fax and 3D copier.

• 한국안광학회지
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• 제7권2호
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• pp.113-121
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• 2002

요즈음 개발되는 각종 카메라, 캠코더, CCTV, 복사기 등의 광학계는 줌과 비구면을 이용하여 작으면서도 광각과 망원을 동시에 수용하고 성능도 우수하다. 본 논문에서는 사진기에 이용되는 2군 줌 렌즈계(비구면 사용)와 3군 줌 렌즈계의 성능을 분석, 평가한 것들을 참고로 하여 사진기용 3군 줌 렌즈계도 설계하였다. 설계한 사진기용 줌 렌즈계는 3군으로 하고 비구면을 도입함으로써 성능향상과 소형화를 도모하였다. 설계결과는 광학계 평가 도구인 유한광선수차, MTF, Seidel 수차 계수 등을 이용하여 참고 모델과 비교하였으며 거의 비슷한 수준이 유지됨을 확인하였다.

• 한국산림과학회지
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• 제98권2호
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• pp.203-211
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• 2009

The study was conducted to examine consumers' awareness and perceptions on forest certification and their willingness to buy and pay price premium for certified wood products especially for selected four wood products. A total of 136 residents in Seoul and Gyeonggi Province were interviewed in the autumn of 2008. Although only 24.3 percent of the consumers are aware of forest certification, 82.4 percent of the respondents recognized the need and significance of forest certification. In general, 77.2 percent of the respondents were willing to buy certified wood products. Majority of the respondents, 84 out of 136 respondents (61.8%) expressed their willingness to pay (WTP) from more than 0 percent to less than 10 percent. Consumers' average WTP for certified wood products was estimated to be 5.6 percent. From the results of the study, lower priced wood products, such as copier paper (WTP=9.8%) and wood frame (WTP=11.6%), have higher price premiums than high priced products, such as wood table (WTP=6.8%) and wood flooring (WTP=7.6%). In conclusion, there could be feasible markets for certified wood products in South Korea as four out of five consumer are willing to pay more for such products. For the forest certification system to be adopted and widely accepted, the perceptions of forest stakeholders including consumers should be further increased.

• 펄프종이기술
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• 제46권4호
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• pp.1-10
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• 2014

In papermaking industry, inorganic fillers are widely used for the purpose of improving opacity, brightness, printability, uniformity and dimensional stability. They are also useful for production costs and energy savings. In the past, inorganic fillers in papermaking industry only focused on micro-scale but recently, new trials on nano-powdered technology are applying. Even nano-powdered fillers are rapidly utilized for improving the optical and surface properties in coating and surface sizing, there still have some problems in wet-end process due to poor dispersibility and retention. In this study, nano-particled calcium carbonate was produced by milling the PCC and its applicability between micro sized and nano sized calcium carbonated was compared in wet-end process, and finally the sheet properties were evaluated. Nano-PCC was not retained in sheet structure without applying retention system, but with retention system nano-powdered PCC was absorbed on fiber surface with expanding the fiber networks. The application of PAM-bentonite system has resulted in high ash retention and bulky structure for copier paper, and good optical properties in brightness and opacity. However, it required to solve the weakness of low tensile property due to interruption of hydrogen bonding by nano fillers.

• 전기학회논문지P
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• 제66권4호
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• pp.188-193
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• 2017

In this paper, a ZVS-PWM high-frequency inverter with a PWM control function is applied to commercial system 220[Vrms], and a resonator type ZVS-PWM high-frequency inverter circuit with a fixed-two methods were proposed. The parameters of the transformer model equivalent circuit of a copier fixing device, which is an essential element in the parameter optimization of the proposed circuit, are obtained by using a high-frequency amplifier and its frequency characteristics are described. The proposed method compared to the existing single-ended ZVS-PFM high frequency inverter can suppress the voltage and current peak value of the power semiconductor switching device and reduce the switching loss. The efficiency of the proposed method itself is 98[%] at rated power output. Also, the efficiency of 96[%] can be obtained even at low output, so that the proposed high frequency inverter is very efficient inverter. The total efficiency from the commercial AC input to the inverter output is 93[%] at rated, which is considered efficient for use in copying machines. In addition, the diode bridge loss accounts for the largest portion of the overall system efficiency distribution. On the other hand, the nonparallel filter has a very low loss.

• 디지털융복합연구
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• 제16권10호
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• pp.235-241
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• 2018

출력물관리 시스템은 출력시 수집된 출력 로그 내에 개인정보(주민번호, 카드번호)가 존재하는지 패턴을 분석하여 사용자에게 경고 메시지 팝업 전달, 인쇄 강제 종료, 관리자에게 메일 발송 및 별도 로그 관리 기능을 갖추어야 한다. 인증 관리 역시 사용자 PC에 Agent를 설치하여 등록되어 있는 사용자만 프린트가 가능하며, 사용자 정보에 따라 작업이 허가되거나 거절될 수 있도록 제한 기능을 갖추어야한다. 또한 복합기로 프린트/복사/스캔 사용 시 ID카드 인증 후 문서 출력 및 복합기를 사용할 수 있으며, ID카드 미사용시 디바이스에 ID/PW를 입력 인증 후 복합기를 사용할 수 있도록 구축해야한다. 본 연구에서는 기존의 출력물 보안 방법들 보다 더욱 우수한 기술을 갖추고 있는 보안 업체인 (주)와우소프트와 공동으로 인터페이스를 개발하여 기록물관리 시스템을 위한 인터페이스들을 구축하였다. 또한 출력물관리를 위한 필요한 기본 기능들의 인터페이스를 설계하였으며 이를 바탕으로 출력물관리 시스템 구축에 기여하였다.

• 한국정보통신학회논문지
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• 제18권10호
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• pp.2433-2442
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• 2014

본 논문에서는 전자사진 기술을 이용하는 프린터, 복사기, 팩시밀리, 복합기 등과 같은 이미징 장치의 효율등급기준에 대한 연구를 수행하였다. 대기전력을 관리하고 있는 현 제도의 문제점을 파악하고 효율관리 필요성을 제안하였으며, 이를 위한 효율 기준을 국내 대기전력저감 프로그램에 등록된 실증 데이터를 기반으로 개발하였다. 효율부여지표를 찾기 위해 상관분석(Correlation Analysis)을 실시하였으며, 인쇄 속도가 가장 큰 상관계수(Correlation Coefficient)를 가짐을 확인하였다. 이를 적용한 복합기, 프린터에 대한 1~5 등급의 효율등급 기준과 에너지 프론티어 기준을 도출하였으며, 정책반영 시 연간 약 650 억 원의 에너지 비용을 절감할 것으로 기대한다.