• Journal of the Korean Chemical Society
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• v.40 no.7
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• pp.515-518
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• 1996

Functional conversion of polybrominated fullerenes has been discussed. These reactions are Friedel-Crafts fullerylation of aromatics, methoxylation and phosphorylation of polybrominated fullerenes.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.15 no.2
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• pp.144-151
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• 2022

In this paper, a 1.5V 256kb eFlash memory IP with low area DC-DC converter is designed for battery application. Therefore, in this paper, 5V NMOS precharging transistor is used instead of cross-coupled 5V NMOS transistor, which is a circuit that precharges the voltage of the pumping node to VIN voltage in the unit charge pump circuit for the design of a low-area DC-DC converter. A 5V cross-coupled PMOS transistor is used as a transistor that transfers the boosted voltage to the VOUT node. In addition, the gate node of the 5V NMOS precharging transistor is made to swing between VIN voltage and VIN+VDD voltage using a boost-clock generator. Furthermore, to swing the clock signal, which is one node of the pumping capacitor, to full VDD during a small ring oscillation period in the multi-stage charge pump circuit, a local inverter is added to each unit charge pump circuit. And when exiting from erase mode and program mode and staying at stand-by state, HV NMOS transistor is used to precharge to VDD voltage instead of using a circuit that precharges the boosted voltage to VDD voltage. Since the proposed circuit is applied to the DC-DC converter circuit, the layout area of the 256kb eFLASH memory IP is reduced by about 6.5% compared to the case of using the conventional DC-DC converter circuit.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.22 no.3
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• pp.49-55
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• 2022

In the next generation mobile communication systems, hybrid massive multiple-input multiple output (MIMO) can be used to highly improve an achievable rate without increasing the number of RF chains. Recently, successive-interference-cancellation (SIC) based hybrid precoder design scheme was proposed to reduce the complexity. However, since this scheme uses simple diagonal matrix for baseband precoding, it cannot solve an interference problem between the transmitted streams. Also, there is a limitation for improving the data rate because of the use of one phase shifter for analog precoding. To solve these problems, in this paper we propose a digital precoding based on the SVD of the effective channel and an analog precoding using two phase shifters. Through simulation, we show that the proposed scheme has better achievable rate and SINR performances than the conventional one.

• Proceedings of the Korea Information Processing Society Conference
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• 2002.04a
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• pp.485-488
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• 2002

J2EE 기반의 웹 애플리케이션의 개발의 장점은 개발자로 하여금 시스템적 문제들에 대한 부담을 절감시켜 비즈니스 로직 개발에 중점을 두도록 하는데 있다. 그러나 시스템적 문제들에 대한 부담은 많이 사라진 반면 실질적인 비즈니스 로직을 개발하는 개발자가 프리젠테이션 계층의 개발 부분에도 참여해야 하고 프리젠테이션 계층에서 사용되는 여러 기술들도 익혀야 하는 부담을 가지게 된다. 따라서 본 연구에서는 이러한 부담을 최소화하고, 웹 애플리케이션 프리젠테이션 계층 프레임워크를 신뢰성 있게 구축하며 프레임워크를 자동 생성하고자 프레임워크를 명세하여 XML 기반의 문서로 변환한다. 이렇게 함으로써 웹 애플리케이션 서버에 의존적인 것들과 또 다른 많은 것들을 확장할 수 있는 여지를 남겨둠으로써 사용자의 편이성을 증가시킬 수 있다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.9C
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• pp.915-921
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• 2009

Lenstra-Lenstra-Lovasz (LLL) algorithm, which is one of the lattice reduction (LR) techniques, has been extensively used to obtain better bases of the channel matrix. In this paper, we jointly apply Seysen's lattice reduction Algorithm (SA), instead of LLL, with the conventional linear precoding algorithms. Since SA obtains more orthogonal lattice bases compared to those obtained by LLL, lattice reduction aided (LRA) precoding based on SA algorithm outperforms the LRA precoding with LLL. Simulation results demonstrate that a gain of 0.5dB at target BER of $10^{-5}$ is achieved when SA is used instead of LLL or the LR stage.

• 프린팅코리아
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• v.7 no.9
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• pp.113-113
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• 2008

PPC 서버는 CIP3/4에 따른 프리프레스장비에 의해 생성된 미리보기 이미지를 통하여 회선율을 산출 및 인쇄조건 데이터를 변환하여 IPC로 전송하고 전송된 데이터는 IPC를 통해 인쇄기에 잉크키 등을 미리설정(프리셋)한다. 인쇄되는 인쇄물의 잉크 키 데이터와 화선율의 데이터를 MCCS(색조관리장치)로 보내고 MCCS에서는 인쇄된 칼라 패치를 분광계로 계측하고, 그 결과를 화면에 표시한다. MCCS는 목표치에 대하여 계측치의 차이를 기준으로 목표치에 가깝게 되도록 잉크키 개도를 조절해 피드백하며, IPC EXPERT 기능용 계측 데이터를 IPC로 보낸다. 따라서, 사람의 눈으로 관리하는 컬러매니지먼트(CMS가 아닌 CIP3/4 데이터의 화선율과 인쇄조건을 PPC서버가 변환하여 IPC에 전송하는 것이다. 인쇄한 인쇄결과물을 MCCS로 계측하여 항상 기준목표 농도치에 맞게 기계에 피드백하고 잉크키 개도를 조절, 색조관리를 함으로써 일정한 품질유지 및 농도관리를 가능(손지절감 및 색조관리의 일관성)하게 하는 시스템이다.

• Proceedings of the Korean Information Science Society Conference
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• 1999.10b
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• pp.215-217
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• 1999

본 논문은 지능형 TV에서 QoS 개선을 위한 MPEG-4 미디어 프리젠터 개발이다. 사용자들이 단순히 수동적인 미디어 사용을 벗어나, 능동적으로 참여 가능한 상태로 변환하며, 다양한 하이퍼미디어를 제공함으로써 정보 서비스의 질적 향상을 지원한다. 화면에 나타난 장면에서 사용자 이벤트를 실시간으로 처리하고, 독립적인 바이너리 세마포 구조인 변형된 원형버퍼를 사용하여 네트워크를 통해 전달된 미디어 스트림을 버퍼링하여 효율적인 상호작용을 지원한다.

• The Journal of the Convergence on Culture Technology
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• v.9 no.1
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• pp.545-550
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• 2023

A pretensioner is a safety device that protects occupants by pulling the seat belt in the event of a vehicle collision. However, since the pretensioner is driven by a explosive method, it is necessary to replace not only the gas generator but also all connecting parts including the manifold after an accident. Therefore, in this paper, we propose an elastic force-based pretensioner that can be used safely and semi-permanently. After analyzing the operating mechanism of the existing pretensioner from a thermodynamic/dynamic point of view, the spring stiffness that can be deployed within an appropriate operating time was determined by converting the gas explosion energy into elastic energy. In addition, the coil spring shape that satisfies the elastic stiffness was designed in consideration of the vehicle interior installation standard. Finally, the operating performance of the pretensioner driven by elastic force was verified through fabrication.

• Journal of IKEEE
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• v.12 no.3
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• pp.151-157
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• 2008

The DNP3.0 and the IEC61850 are the most important standards in the SCADA systems for the power. Each standard has strength and weakness, so they will coexist for a while. This paper presents a design of the gateway function between DNP3.0 and IEC61850. Both standards use object-oriented modelling methods, so, they have some similarities. However, the DNP3.0 objects are described by object number and index, and the IEC61850 objects are described by name. So there should be mapping function between the object number and index of DNP3.0 objects and the object name of IEC61850 objects. We analyse the communication profiles of both standards, and shows the service-primitive mapping table and the procedure of the gateway function.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.6
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• pp.744-749
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• 2016

This paper presents the design of a computer-generated hologram for beam control of an LCOS-based wavelength selective switch, which is the core technology for next-generation ROADM. By introducing a computer-generated hologram instead of general grating patterns to control the LCOS device, we contribute to building a more efficient wavelength selective switch. With the use of phase modulation properties of LCOS devices, we designed the hologram for five-port output and a 40-channel wavelength selective switch. We applied a multi-level phase modulation technique with the Gerchberg-Saxton algorithm to produce the hologram, which is easily scalable to any different type of wavelength selective switch. With an experimental setup, we verified the usability of the hologram designed for five-port output. We also suggest a hologram design technique for beam control of a 40-channel wavelength selective switch.