• 제목/요약/키워드: CTR

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Effect of misconvergence on resolution of color CRT monitor (칼라 CRT 모니터의 misconvergence에 따른 분해능 평가)

  • 김태희;이윤우;조현모;이인원;최옥식;정봉교
    • Korean Journal of Optics and Photonics
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    • v.10 no.2
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    • pp.138-145
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    • 1999
  • By varying the beam current of a color CRT(cathode ray tube) monitor, the misconvergence, spot size, display luminance, and chromaticity coordinate of a white pattern were measured at 4 screen positions. The misconvergence was measured with a linear CCD (charge coupled-device). The resolution was obtained by using SQRI (square root integral) method. The misconvergence of a color monitor was not influenced by the beam current but by the screen position. The misconvergence on a screen perimeter caused the resolution to decrease.

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Analysis of the Empirical Effects of Contextual Matching Advertising for Online News

  • Oh, Hyo-Jung;Lee, Chang-Ki;Lee, Chung-Hee
    • ETRI Journal
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    • v.34 no.2
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    • pp.292-295
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    • 2012
  • Beyond the simple keyword matching methods in contextual advertising, we propose a rich contextual matching (CM) model adopting a classification method for topic targeting and a query expansion method for semantic ad matching. This letter reports on an investigation into the empirical effects of the CM model by comparing the click-through rates (CTRs) of two practical online news advertising systems. Based on the evaluation results from over 100 million impressions, we prove that the average CTR of our proposed model outperforms that of a traditional model.

PSPICE Modeling of Commercial ICs for Switch-Mode Power Supply (SMPS) Design and Simulation

  • Yi, Yun-Jae;Yu, Yun-Seop
    • Journal of information and communication convergence engineering
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    • v.9 no.1
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    • pp.74-77
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    • 2011
  • PSPICE modeling of a commercial LED driver IC (TOP245P) and PC817A optocoupler is proposed for the switch-mode power supply (SMPS) (applicable to LED driver) design and simulation. An analog behavioral model of the TOP245P IC including the shunt regulator, under-voltage(UV) detection, over-voltage(OV) shut-down and SR flip-flop is developed by using PSPICE. The empirical equation of PC817A current transfer ratio (CTR) is fitted from the datasheet of PC817A. Two types of SMPSs are simulated with the averaged-model and switching-model. The simulation results by the proposed PSPICE models are in good agreement with those in the data sheet and an experimental data.

An Implementation of GCM Authenticated Encryption based on ARIA Block Cipher (ARIA 블록암호 기반의 GCM 인증암호 구현)

  • Kim, Ki-Bbeum;Sung, Byung-Yoon;Shin, Kyung-Wook
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2017.05a
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    • pp.185-187
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    • 2017
  • 국제 표준화 기구인 ISO/IEC와 NIST(National Institute of Standards and Technology)에서는 정보 유출 방지 및 정보의 유효성 인증을 위해 다양한 암호 기법들을 표준으로 권고하고 있다. 그 중 NIST SP 800-38D에서 표준으로 권고된 GCM(Galois/Counter Mode) 인증 암호화 모드는 블록암호의 CTR 운영모드와 GHASH를 이용하여 메시지의 기밀성과 무결성을 동시에 제공하는 운영모드이다. 본 논문에서는 ARIA 블록암호 기반의 ARIA-GCM 프로세서를 Verilog HDL로 모델링 하고, Virtex5 FPGA로 구현하여 정상 동작함을 확인하였다. $0.18{\mu}m$ 공정의 CMOS 셀 라이브러리로 합성한 결과 20 MHz의 동작주파수에서 44,986 GE로 구현되었다.

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A Hardware Implementation of Ultra-Lightweight Block Cipher PRESENT Supporting Four Modes of Operation (4가지 운영모드를 지원하는 초경량 블록암호 PRESENT의 하드웨어 구현)

  • Kim, Ki-Bbeum;Cho, Wook-Lae;Shin, Kyung-Wook
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2016.05a
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    • pp.151-153
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    • 2016
  • 80/128-비트 마스터키 길이와 ECB, CBC, OFB, CTR의 4가지 운영모드를 지원하는 PRESENT 경량 블록암호 프로세서를 설계하고, Virtex5 FPGA에 구현하여 정상 동작함을 확인하였다. PRESENT 크립토 프로세서를 $0.18{\mu}m$ 공정의 CMOS 셀 라이브러리로 합성한 결과 8,237 GE로 구현되었으며, 최대 434 MHz 클록으로 동작하여 868 Mbps의 성능을 갖는 것으로 예측되었다.

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Temperature Dependence of Energy Gap and Thermodynamic Function Properties of Coblt-doped $Cd_4GeS_6$Single Crystals (Cobalt를 첨가한 $Cd_4GeS_6$ 단결정에서 Energy Gap의 온도의존성 및 열역학적 함수 추정)

  • 김덕태
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.11 no.9
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    • pp.693-699
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    • 1998
  • In this work $Cd_4GeS_6:Co^{2+}$(0.5mole%) single crystals were grown by the chemical transporting reactiov(CTR) method using high purity(6N) elements. The grown single crystals crystallized in a monoclinic structure(space group Cc). The direct optical energy gap of this single crystals was found to be 2.445eV at 300K and the temperature dependence of optical energy gap was fitted well to Varshni equation. But at temperatures lower than 70K an anomalous temperature dependence of the optical energy gap was obtained. This anomalous temperature dependence accored well with the anomalous temperature dependence of the unit cell volume. Also, the entropy, enthalpy and heat capacity were deduced from the temperature dependence of optical energy gaps.

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Growth and optical properties of undoped and Co-doped CdS single crystals (CdS 및 $CdS:Co^{2+}$ 단결정의 성장과 광학적 특성)

  • Kim, N.O.;Bang, T.H.;Hyun, S.C.;Park, K.H.;Park, H.;Oh, S.K.
    • Proceedings of the KIEE Conference
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    • 2002.06a
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    • pp.94-97
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    • 2002
  • CdS and $CdS:Co^{2+}$ single crystals were grown by CTR method using iodine as transport material. The grown single crystals have defect chalcopyrite structure with direct band gap. The optical energy band gap was decreased according to add of Co-impurity. We can observed the Co-impurity optical absorption peaks assigned to the $Co^{2+}$ ion sited at the $T_d$ symmetry lattice and we consider that they were attributed to the electron transitions between energy levels of ions.

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An AES-GCM Crypto-core for Authenticated Encryption of IoT devices (IoT 디바이스의 인증암호를 위한 AES-GCM 암호코어)

  • Sung, Byung-Yoon;Kim, Ki-Bbeum;Shin, Kyung-Wook
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2017.10a
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    • pp.253-255
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    • 2017
  • 본 논문에서는 IoT 디바이스의 인증암호를 위한 AES-GCM 암호코어를 설계하였다. AES-GCM 코어는 블록암호 AES와 GHASH 연산으로 기밀성과 무결성을 동시에 제공한다. 기밀성 제공을 위한 블록암호 AES는 운영모드 CTR과 비밀키 길이 128/256-bit를 지원한다. GHASH 연산과 AES 암호화(복호화)의 병렬 동작을 위해 소요 클록 사이클을 일치시켜 GCM 동작을 최적화 하였다. 본 논문에서는 AES-GCM 코어를 Verilog HDL로 모델링 하였고 ModelSim을 이용한 시뮬레이션 검증 결과 정상 동작함을 확인하였으며 Xilinx Virtex5 XC5VSX95T FPGA 디바이스 합성결과 4,567 슬라이스로 구현되었다.

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Crystal Growth of $Cd_4SnSe_6:Co^{2+}$ Single Crystals ($Cd_4SnSe_6:Co^{2+}$ 단결정의 성장)

  • Kim, D.T.;Song, M.J.;Kim, H.G.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.07a
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    • pp.607-608
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    • 2005
  • In this paper, author describe the undoped and $Co^{2+}$(0.5mole%) doped $Cd_4SnSe_6$ single crystals were grown by the chemical transport reaction(CTR) method. The grown single crystals crystallize in the monoclinic structure of space group Cc and have the direct band gap structure. The energy gaps of them are 1.68 eV for $Cd_4SnSe_6$ and 1.50 eV for $Cd_4SnSe_6:Co^{2+}$ at 300K respectively.

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Hawkes Process based Generative Model in Mobile AD Technology (모바일 광고 기술에서 Hawkes 프로세스 기반 생성 모델에 관한 연구)

  • Hwang, Sangwon;Joe, Inwhee
    • Proceedings of the Korea Information Processing Society Conference
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    • 2019.05a
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    • pp.504-507
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    • 2019
  • 모바일 광고 기술(AD Tech)분야에서 기계학습은 사용자별 CTR(Click Through Ratio) 예측[1]에 국한되어 왔으며 2016 년도부터 시행된 GDPR(General Data Protection Regulation)[2] 정책으로 인하여 AD Tech 관련 사업자의 사용자 개인정보 접근이 제한되어왔다. 그 결과 Feature Data 에 기반한 사용자 타겟팅 및 Ad Tech 산업에서 기계 학습 기술을 적용하는데 현실적 어려움을 가져왔다. 본 논문에서는 기존 연구와 현실적 한계를 극복하기 위하여 사용자가 아닌 매체별 클릭 분포를 예측하는 Hawkes Process 에 기반한 생성모델을 제안하고 그 가능성을 살펴본다.