• 한국진공학회지
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• 제10권1호
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• pp.27-30
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• 2001

절연보호막 처리된 Al-1%Si 박막배선에서 DC와 PDC 조건하에서의 Electromigration 현상에 관하여 조사하였다. $SiO_2$와 PSG/$SiO_2$ 절연보호막 층을 갖는 박막배선은 표준 사진식각 공정으로 제작되었고, 테스트라인 길이는 100, 400, 800, 1200, 1600 $\mu\textrm{m}$이다. Al-l%Si 박막배선에 고정된 전류밀도 $1.19\times10^7\textrm{A/cm}^2$의 DC와 duty factor가 0.5인 1Hz의 주파수에 고정된 전류밀도 $1.19\times10^7\textrm{A/cm}^2$의 PDC를 인가하였다. Electromigration 테스트에서 PSG/$SiO_2$ 절연보호막 시편의 Electromigration 저항성이 $SiO_2$ 절연보호막 시편보다 우수함을 알 수 있었다. PDC 에서 박막 배선의 수명이 DC 보다 2-4배 정도 길게 나타났으며, 박막 배선의 길이가 증가 할 수록 수명이 감소하다가 임계길이 이상에서 포화되는 경향을 보인다. Electromigration에 의한 결함 형태로는 전기적 개방을 야기시키는 보이드와 전기적 단락을 야기시키는 힐록이 지배적이다.

• 한국정보통신학회논문지
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• 제21권2호
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• pp.265-276
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• 2017

본 논문에서는 하중 적분 PDC 제어 기법과 T-S 퍼지 외란 관측기를 이용한 강인하면서도 보다 정확한 이동 로봇의 궤도 추적 제어 방법을 제안한다. 하중 적분 PDC 제어 기법은 PDC 제어 기법에 하중 적분 항을 추가함으로써 정상상태 오차를 감소시켜 준다. T-S 퍼지 외란 관측기는 T-S 퍼지 모델로 표현된 비선형 시스템에 대해 외란을 추정하고 상쇄시킬 수 있도록 한다. 따라서, T-S 퍼지 외란 관측기에 기반한 궤도 추적 제어기는 강인한 궤도 추적 성능을 보여준다. 또한, 본 연구에서는 $B\acute{e}zier$ 곡선에 의한 가속도 제한을 갖는 경로 설계 방법에 의해 초기 접근 경로를 설계함으로써, 이동 로봇의 초기 위치가 기준 궤도의 초기 위치와 다를 때 제어 입력이 매우 커지게 되어 실제적으로 사용할 수 없게 되는 문제를 해결한다. 제안된 궤도 추적 제어기의 성능을 시뮬레이션을 통해서 입증하였다.

• 한국인터넷방송통신학회논문지
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• 제16권6호
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• pp.177-181
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• 2016

본 논문에서는 저널링을 사용하는 전가상화 시스템에서 호스트 캐시의 효율을 높이기 위한 기법을 제안한다. 게스트의 저널링 데이터는 쓰기를 위해 호스트 캐시에 한번만 접근되는 패턴과 빈번한 sync 명령으로 인해 캐시의 효율을 감소시킨다. 이러한 성능 감소를 줄이기 위하여 본 논문에서는 게스트의 저널링 데이터가 호스트 캐시에 접근하는 것을 막는 PDC라는 기법을 제안한다. PDC는 Linux 4.14 버전에서 QEMU-KVM 2.1 버전을 기반으로 구현하였으며, 다양한 워크로드에서 3-32%의 성능 향상을 보였다.

• 전기학회논문지
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• 제57권11호
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• pp.2086-2094
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• 2008

Finding a planar surface on 3D space is very important for efficient and safe operation of a mobile robot. In this paper, we propose a method using a plane detection cell (PDC) and iterative randomized Hough transform (IRHT) for finding the planar region from a 3D range image. First, the local planar region is detected by a PDC from the target area of the range image. Each plane is then segmented by analyzing the accumulated peaks from voting the local direction and position information of the local PDC in Hough space to reduce effect of noises and outliers and improve the efficiency of the HT. When segmenting each plane region, the IRHT repeatedly decreases the size of the planar region used for voting in the Hough parameter space in order to reduce the effect of noise and solve the local maxima problem in the parameter space. In general, range images have many planes of different normal directions. Hence, we first detected the largest plane region and then the remained region is again processed. Through this procedure, we can segment all planar regions of interest in the range image.

• 한국대기환경학회지
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• 제22권1호
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• pp.43-51
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• 2006

Nonthermal plasma-driven catalysis (PDC) was investigated for the decomposition of benzene and toluene as model compounds of volatile organic compounds (VOCs) at atmospheric pressure and low temperature. Two types of catalysts Ag/$TiO_{2}$ and Pt/$\gamma-Al_{2}O_{3}$ were tested in this study. The amount of catalysts packed in the PDC reactor did not influence on the decomposition efficiency of benzene. The type of catalysts also had no influence on the decomposition efficiency of toluene and carbon balance. The Ag/$TiO_{2}$ catalyst showed constant $CO_{2}$ selectivity of about $73\%$ regardless of the specific input energy. However, the selectivity of $CO_{2}$ was greatly enhanced with the Pt/$\gamma-Al_{2}O_{3}$ catalysts, and reached $97\%$ at 205 J/L. Two test runs with 20 fold difference in the gas flow clearly indicated that lab-scale data can be successfully applied for the scaling-up of PDC system.

• 한국정보시스템학회지:정보시스템연구
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• 제27권3호
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• pp.25-42
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• 2018

Purpose The purpose of this study focused on adopting production systems in cognitive psychology to improve the extraction process of persuasive design characteristics for healthcare-related mobile applications. Design/Methodology/Approach A research approach with four stages was developed. We developed and updated the evaluation guideline for persuasive design characteristics (PDC). We tried to summarize and analyze each of 28 PDC and prepared related production rules. Verification process for both guideline approach and production system approach were performed. Top one hundred apps from both medical category and health and Fitness category were selected and evaluated by two approaches. By comparing the results of the two approaches, we tried to explain the improvement and reliability of introducing the production system in the PDC extraction process. Findings Based on the updated guideline for healthcare-related mobile applications, a production system in cognitive psychology was developed. By comparing the PDC extraction results by two approaches, production system showed a better improvement for evaluation precision and efficiency for decision-making process. The findings of this study can be used for researchers and app developers to apply production system to analyze, evaluate, and develop better healthcare-related apps with persuasion.

• 동력기계공학회지
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• 제13권5호
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• pp.67-75
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• 2009

Recently, the higher capacity waste heat recovery PDC clean ventilation system has a tendency which is increasing due to the excellent energy reduction in factory, big building, and so on. This system was developed to complement the room environment which is deteriorated. However, the researches and technologies about this system were not well studied. Specially, the characteristic for heat exchanger element used to this system were not well known. Therefore, this study was carried out to evaluate the mechanical properties of the heat exchanger element as the core parts compose of this system. From results, tensile strength and elongation of the plate type heat exchanger element had about 10.11~14.32 kgf/$mm^2$ and 8.0~16.2%, respectively.

• 대한화학회지
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• 제32권4호
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• pp.351-357
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• 1988

Propanediol-1,2-carbonate (PDC) 용매중에서 우라닐 화합물의 전기화학적 환원반응 메카니즘을 전압전류법으로 조사하여 봉우리 전위의 위치, 한계전류의 성질, 한계전류와 온도 및 농도의 관계, 전극반응의 가역성, 양성자 공여체인 페놀의 첨가에 대한 영향등을 기술하였다. 또 우라닐 화합물의 수용액에 PDC의 양을 점차 증가시킨 혼합용매에서의 전극반응도 조사하였다. 우라닐 화합물의 비가역적 전극반응에 관여하는 전이계수 및 속도상수등의 반응 속도론적 파라미터를 Koutecky의 이론에 따라 결정하였으며, ${\Delta}H,\;{\Delta}G\;및\;{\Delta}S$등에 열역할적 파라미터도 계산하였다.

• 한국분말재료학회지
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• 제23권5호
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• pp.364-371
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• 2016

This study investigates the thermal shock property of a polycrystalline diamond compact (PDC) produced by a high-pressure, high-temperature (HPHT) sintering process. Three kinds of PDCs are manufactured by the HPHT sintering process using different particle sizes of the initial diamond powders: $8-16{\mu}m$ ($D50=4.3{\mu}m$), $10-20{\mu}m$ ($D50=6.92{\mu}m$), and $12-22{\mu}m$ ($D50=8.94{\mu}m$). The microstructure observation results for the manufactured PDCs reveal that elemental Co and W are present along the interface of the diamond particles. The fractions of Co and WC in the PDC increase as the initial particle size decreases. The manufactured PDCs are subjected to thermal shock tests at two temperatures of $780^{\circ}C$ and $830^{\circ}C$. The results reveal that the PDC with a smaller particle size of diamond easily produces microscale thermal cracks. This is mainly because of the abundant presence of Co and WC phases along the diamond interface and the easy formation of Co-based (CoO, $Co_3O_4$) and W-based ($WO_2$) oxides in the PDC using smaller diamond particles. The microstructural factors for controlling the thermal shock property of PDC material are also discussed.

• Archives of Pharmacal Research
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• 제20권1호
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• pp.7-12
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• 1997

Glutamate uptake inhibitor, L-trans-pyrrolidine-2, 4-dicarboxylate (PDC, $20{\mu}M$) elevated basal and N-methyl-D-aspartate (NMDA, $100{\mu}M$)-induced extracellular glutamate accumulation, while it did not augment kainate $100{\mu}M$-induced glutamate accumulation in cultured cerebellar granule neurons. However, pretreatment with PDC for 1 h significantly reduced NMDA-induced glutamate accumulation, but did not affect kainate-induced response. Pretreatment with glutamate $(5{\mu}M)$ for 1 h also reduced NMDA-induced glutamate accumulation, but did not kainate-induced response. Upon a brief application (3-10 min), PDC did neither induce elevation of intracellular calcium concentration $([Ca^{2+}]_i)$ nor modulate NMDA-indLiced $[Ca^{2+}]_1$ elevation. Pretreatment with PDC for 1 h reduced NMDA-induced $[Ca^{2+}]_1$ elevation, but it did not reduce kainate-induced $[Ca^{2+}]_1$ elevation. These results suggest that glutamate concentration in synaptic clefts of neurana cells is increased by prolonged exposure (1 h) of the cells to PDC, and the accumulated glutamate subsequently induces selective desensitization of NMDA receptor.