1,731,975 research outputs found
Min Lee
No full text학위논문(박사)--아주대학교 일반대학원 :전자공학과,2014. 8List of Figures
Abbreviation
1 Introduction
1.1 Background and Motivation
1.2 Contributions
2 Closed-form Ergodic Cooperative Capacity for CoMP Joint Diversity Transmission
2.1 CoMP JDTN Model and Capacities
2.2 PDF of Instantaneous DC-SNR
2.3 Closed-form ECC
2.4 Proof of Theorem 2.1
2.5 ECC Behaviors
3 Joint Power Allocation for Ergodic Cooperative Capacity Maximization
3.1 CoMP JDTN Model
3.2 Problem Formulation and Optimum Power Allocation
3.3 JPA for Co2P JDT under Unity TCPP
3.4 JPA for Co2P JDT under Non-unity TCPP
3.5 JPA for Co3P JDT
3.6 Numerical Results
4 Approximations for Ergodic Capacities in Rayleigh fading Channels
4.1 Approximations for EC of a Single-branch Rayleigh-faded Channel
4.2 Approximation for ECC of Two-branch Rayleigh-faded Channels at the Balanced Point
4.3 Approximation for ECC of Three-branch Rayleigh-faded Channels at the Balanced Point
5 Joint Power Allocation for Total Coordination Point Power Minimization
5.1 Problem Formulation and Optimum Power Allocation
5.2 Approximated Expressions of JPA for Co2P JDT
5.3 JPA for Co2P JDT using Duality Condition
5.4 JPA for Co3P JDT using Duality Condition
5.5 Numerical Results
6 Conclusions
ReferencesDoctoralIn this dissertation, we study a coordinated multi-point (CoMP) joint diversity transmission network (JDTN) in Rayleigh fading channels.
First, as a useful tool to analyze the performance of the CoMP JDTN, we derive a closed-form ergodic cooperative capacity (ECC) expression of the CoMP JDTN in Rayleigh fading channels. To obtain the closed-form ECC expression, we first derive a closed-form probability density function (PDF) of the instantaneous diversity-combined signal-to-noise ratio, and then a closed-form ECC expression for the CoMP JDTN by using the derived closed-form PDF.
Second, using the closed-form ECC expression, we deal with the joint power allocation (JPA) problem for the CoMP JDTN with the constraint on the total coordination point power (TCPP), aimed at maximizing the ECC in Rayleigh fading channels. We first consider the coordinated two-point (Co2P) JDTN that consists of two coordinated transmission points (CTPs) - CTP1 and CTP2 - and a user equipment, under the unity TCPP. We obtain the relationship that yields the optimum CTP1 power with respect to the mean branch gain-to-noise ratios (GNRs). Then, we introduce two simple log-linear approximated (LLA) expressions for the optimum CTP1 power, with exact slope and approximated slope, respectively, at the balanced point. Using the LLA expressions, we also draw efficient criteria for turning off Co2P joint diversity transmission (JDT). Next, we extend the JPA problem to the case of a non-unity TCPP constraint. We furthermore introduce more accurate log-quadratic approximated (LQA) expressions for obtaining the CTP powers. Then, we extend our study to a coordinated three-point (Co3P) JDTN. Given the mean branch GNRs, we obtain a LLA expression for obtaining the optimum power of the third CTP (i.e., the worst quality-providing CTP). After obtaining the third-CTP power, we obtain the CTP powers of the two better quality-providing CTPs by invoking the LLA CTP power expressions for Co2P JDT power allocation, under the remaining power that is given by the TCPP minus the third-CTP power.
Finally, we deal with the JPA problem for the CoMP JDTN with an ergodic rate requirement in Rayleigh fading channels, aimed at minimizing the TCPP. Prior to the JPA problem for minimizing the TCPP in the CoMP JDTN, we present several approximate expressions for the EC of a single-branch Rayleigh-faded channel and the ECC of cooperative-branch Rayleigh-faded channels. Next, for the Co2P JDTN, we derive an optimality-conserving condition for the optimum CTP powers. We present two simple expressions such as a LLA expression for optimum CTP1 power and a LQA expression for optimum CTP2 power. Then, we present an improved JPA method for the Co2P JDTN, which can maintain the TCPP at an almost optimum level for the ergodic rate requirement. In this improved method, we obtain a much better TCPP approximation to give the required ergodic rate by using the linear interpolation of two known nearby sets of TCPP versus the ergodic rate. Using the TCPP approximation, we then obtain two CTP powers by using the LQA and LLA CTP power expressions of Co2P JDT for ECC maximization under the TCPP constraint. We further extend this method to the Co3P JDTN according to the similar process to that in the Co2P JDTN
Sang-Min Lee
No full text학위논문(석사)--아주대학교 공학대학원 :화학생명공학과,2019. 2최근 통신 및 전자기기 분야에서 소형화, 경량화, 박막화 및 소재의 친환경화 경향에 더하여 높은 휴대성과 디자인 요소를 중시하는 요구 조건에 맞춰 유연한 소자 개발에 관한 연구가 중요시되고 있다. 디스플레이용 도전성 필름은 전도성 물질로 형성된 구조로, 디스플레이, 백라이트, 터치 패널, 태양전지, 전자파 차단 재료 등에 폭넓게 이용되고 있다. 특히, 최근 휴대 전화, 태블릿 PC라고 불리는 전자기기 등으로의 터치 패널의 도입률이 높아지고 있어 도전성 필름의 수요가 급격히 확대되고 있다. 디스플레이 내부에 사용되는 전도성 조성물은 열경화 과정을 거쳐 필름으로 제조된다. 이러한 필름은 대전방지효과 및 기판보호기능이 부여되어야 하며, 패널의 글래스 식각 공정부터 완제품 공정까지 제거되지 않고 사용되므로 내열성 또한 요구된다. 통상적으로 전도성 조성물은 높은 표면 저항값으로 인해, 화상표시장치 패널의 이물 부착 현상이 쉽게 발생된다. 또한, 통상적으로 전도성 조성물은 알콜성계 용매를 포함하고 있으며, 알콜성계 용매는 상분리가 발생되며, 휘발성이 저하되어 용해도가 감소되는 문제점이 있다. 상기 전도성 조성물에 있어서, 용매, 대전방지제의 종류와 함유량, 또한, 상기 필름의 표면저항 값은 대전방지효과, 기판보호기능 및 내열성에 영향을 미치는 요소를 개선하고 기초 소재로 활용이 가능한 연구를 진행 하고자 한다. 본 연구는 디스플레이 필름소재로 가능성이 있는 물성을 구현하고자 연구 하였으며 향후 소재연구에 많은 도움이 되리라 생각한다.Ⅰ. 서 론 1
1. 연구의 필요성 및 연구 방향 1
Ⅱ. 본 론 2
1. 목표물성 및 원자재 선정 2
1.1 실험목표 물성 2
1.2 원자재 선정 2
2. 제조 방법 5
2.2 분산 공정 5
3. 평가항목 및 결과 6
2.2 Resin 제조 공정 6
3.1 점도 평가 6
3.2 경도 평가 7
3.3 고형분 함량 평가 9
3.4 Cl 함량 분석 11
3.5 RoHS(유해물질사용제한) 분석 11
3.6 내 알코올성 평가 13
3.7 투과율 평가 14
3.8 Color Level 평가 16
3.9 표면저항 평가 17
Ⅲ. 결 론 19
1. 결론 19
1.1 연구결과 19
1.2 향후 연구방향 19
참고 문헌 20
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