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Priority-Driven Resource Allocation with Reuse for Platooning in 5G Vehicular Network
Full text linkRecently, Vehicle-to-Everything (V2X) communication has emerged as a critical technology for enhancing the safety and traffic management of autonomous vehicles. Developing a resource allocation algorithm that enables autonomous vehicles to perceive and react to their surroundings in real time through fast and reliable communication is of paramount importance. This paper proposes a novel resource allocation algorithm that minimizes the degradation of communication performance for non-platoon vehicles while ensuring low-latency, high-reliability communication within vehicle platoons. The proposed algorithm prioritizes platoon vehicles and enhances resource efficiency by simultaneously applying interference-based and distance-based resource reuse techniques. Performance evaluations conducted using the Simu5G simulator demonstrate that the proposed algorithm consistently maintains the average resource allocation rate and delay for both platoon and non-platoon vehicles, even as the number of platoons increases. Specifically, in a congested environment with 60 general vehicles and five platoons, the proposed algorithm achieves an average resource allocation rate of over 90%, significantly outperforming existing algorithms such as Max-C/I, which achieves only 58%, and the priority-based algorithm with 54%, ensuring reliable communication for all vehicles. © 2025 by the authors.TRUEsciessciscopu
TARGET LOCATION DETERMINE APPARATUS AND METHOD THEREOF
No full text타켓 위치 결정 장치가 개시된다. 본 타켓 위치 결정 장치는 레이더 신호를 방출하고, 타켓으로부터 반사된 레이더 신호를 수신하는 레이더 장치, 및 수신된 레이더 신호에 기초하여 타켓의 위치를 결정하는 프로세서를 포함하며, 프로세서는 수신된 레이더 신호를 이산 푸리에 변환(DFT : Discrete Fourier Transform)을 적용하고, 이산 푸리에 변환이 적용된 레이더 신호에 기초하여 신호 대 잡음비(SNR)를 추정하고, 추정된 신호 대 잡음비가 기설정된 값 미만이면, RELAX 알고리즘을 이용하여 타겟의 위치를 결정하고, 추정된 신호 대 잡음비가 기설정된 값 이상이면, 부공간 알고리즘을 이용하여 타겟의 위치를 결정한다
A free-standing sulfone-based solid-state electrolyte mitigating the release of crystal water from the Prussian blue cathode for high voltage potassium batteries
No full textPrussian blue (PB) and its analogues are emerging cathode materials for potassium batteries due to their 3D open framework allowing facile ion diffusion. However, the crystal water, an inherent component of PB structure, can be released into the electrolytes especially during high voltage operation, causing detrimental side reactions and rapid degradation of potassium batteries. To address this challenge, we present a free-standing sulfone-based solid-state electrolyte (FSSE) comprising potassium bis(fluorosulfonyl)imide, dimethyl sulfone, and UV-cured trimethylolpropane ethoxylate triacrylate network. The FSSE effectively prevents the release of crystal water from PB cathode while exhibiting suitable electrolyte properties including decent ionic conductivity (2.2 × 10−4 S cm−1 at 25 °C), exceptional oxidative stability (∼4.8 V vs. K+/K), and intimate contact with porous composite PB electrodes. K||PB cells utilizing FSSE demonstrate superior cyclability compared to a liquid carbonate electrolyte (74.6 % vs 53.3 % capacity retention over 200 cycles). The solid-state electrolyte possessing the ability to block crystal water provides a promising avenue for exploring diverse PB cathode materials for high-voltage potassium batteries. © 2025 Elsevier B.V.FALSEsciescopu
Revisiting Masked Image Modeling with Standardized Color Space for Domain Generalized Fundus Photography Classification
No full textMasked image modeling, Domain generalization, Fundus photography, Diabetic retinopathyI. INTRODUCTION 1
II. RELATED WORKS 4
2.1 CFP Classification 4
2.2 Foundation Models 4
2.3 Domain Generalization (DG) 4
III. METHOD 6
3.1 Problem Setup 6
3.2 Overview 6
3.3 Masked Image Transformation 6
3.3.1 Standardized color transformation 6
3.3.2 Masked image modeling 8
3.4 Joint Representation Learning 9
3.4.1 Cross-Attention module 9
3.4.2 Classification with joint representation 10
IV. EXPERIMENTS 11
4.1 Datasets 11
4.1.1 4DR 11
4.1.2 APTOS-Messidor 11
4.1.3 Glaucoma 11
4.2 Experimental Details 11
4.3 Experimental Scenarios 12
4.3.1 Comparison against recent DG methods 12
4.3.2 Scalability in diverse datasets 12
4.3.3 Ablation studies 12
4.3.4 Impact on masked image modeling 13
4.3.5 Impact on transformed image 13
4.3.6 Impact on cross-attention 13
V. RESULTS 14
5.1 Comparison Against Recent DG Methods 14
5.2 Scalability in Diverse Datasets 14
5.3 Ablation Studies 14
5.4 Impact on Masked Image Modeling 15
5.5 Impact on Transformed Image 16
5.6 Impact on Cross-Attention 17
5.7 Additional Results 17
5.7.1 Impact on the blended image Zi 17
5.7.2 Impact of class label use on color transformation 18
5.7.3 Additional transformed images 20
VI. CONCLUSION 23
References 24MasterdCollectio
뷰티글라브리딘은 세포 노화를 감소시키고 미토콘드리아 기능을 증가시키며 노화 세포 내 대사를 변화시킨다
No full textcellular senescence, vutiglabridin, Paraoxonase2, mitochondria, metabolismⅠ. Introduction 1
Ⅱ. Materials and Methods 6
2.1 Cell culture 6
2.2 Cell growth assay 6
2.3 Senescence Associated-β-galactosidase (SA-β-gal) assay 7
2.4 RNA extraction and cDNA synthesis 8
2.5 Quantitative real-time PCR 8
2.6 Extracellular Flux assays 9
2.7 Confocal microscopy and Electron microscopy 10
2.8 Western blot 11
2.9 NAD+ and NADH measurement 12
2.10 Cell viability assay 13
2.11 Senescence induction in LO2 cells 14
2.12 generation of PON2 Knock-Down cells 14
Ⅲ. Results 15
3.1 Vutiglabridin treatment alleviates replicative senescence of HDFs 15
3.2 Long-term culture with vutiglabridin reduces mitochondrial dysfunction in high-passage HDFs 20
3.3 Long-term culture with vutiglabridin modulates the expression of the metabolic regulatory protein in high-passage HDFs 27
3.4 Treatment of low concentration hydrogen peroxide provokes ROS-induced senescence in L02 hepatocytes 30
3.5 Vutiglabridin alleviates ROS-induced senescence in LO2s with mitochondria morphological change 35
Ⅳ. Discussion 41
Ⅴ. Reference 44MasterdCollectio
전기화학적 CO2 환원 중 수용성 전해질이 금속-유기 골격 촉매의 재구성에 미치는 영향에 관한 연구
No full textCarbon dioxide electroreduction, Metal-organic frameworks, Reconstruction, Catalytic active siteList of Contents
Abstract i
List of Contents ii
List of Tables ⅳ
List of Figures v
Ⅰ. Introduction
1.1 Electrochemical CO2 Reduction Reaction 1
1.2 Cu-based Electrocatalyst for CO2RR 6
1.3 Metal-organic Frameworks 8
1.3.1 Utility of Metal-organic Frameworks as Electrochemical Catalysts 8
1.3.2 Water Stability of Metal-organic Frameworks 10
1.4 Reconstruction of Catalyst in CO2RR 14
1.4.1 Reconstruction of Metal-based Catalyst 14
1.4.2 Reconstruction of MOFs in CO2RR 15
1.5 Research Motivation and Strategy 17
Ⅱ. Theoretical Background
2.1 Electrochemical Reaction 19
2.2 Mechanisms of CO2 Reduction 20
2.3 Performance Evaluation Indicators of CO2 Reduction Catalyst 22
2.4 CO2RR Electrolyzer and Electrode 23
2.5 Electrolytes in CO2RR 26
2.6 Chemical State Transformation of Cu in Aqueous Electrolyte 27
Ⅲ. Experimental
3.1 Synthesis of Cu-BDC and Cu-MOF-74 32
3.2 Material Characterization 33
3.3 Electrode Preparation 34
3.4 Evaluation of CO2 Reduction Performance 35
Ⅳ. Results and Discussion
4.1 Mechanisms of Structural Change Depending on the Degree of Hydrophobicity of the MOF and the Electrolyte Environment 37
4.1.1 Cu-based MOFs Characterization 41
4.1.2 Analysis of the MOFs Structural Change as the pH of the Electrolytes 44
4.2 Variation of CO2RR Selectivity with the Degradation Behavior of MOFs 52
4.3 Identify the Cause of Variation in CO2RR Selectivity due to Different Reconstructions in MOFs 60
V. Conclusion 68
VI. Reference 71
요약문 76MasterdCollectio
향상된 코티솔 센싱을 위한 전사공정된 유연 트랜지스터 설계 및 공정최적화
No full textMicroelectromechanical system (MEMS), Indium oxide, Cortisol, MOSFET, Process optimization본 논문에서는 스트레스 호르몬인 코티솔을 검출하기 위한 유연 트랜지스터 기반 센서를 설계하고 최적화 하였다. 코티솔은 체액 내에 녹아있으며 일주기 및 스트레스를 받는 환경에서 농도가 달라지는 대표적인 바이오마커이다. 기존의 스트레스 측정 방식은 주관적 평가가 개입되거나 복잡한 장비가 필요한 생체 신호 측정에 기반하여 일상적인 환경에서 모니터링이 어렵다는 단점이 있다. 이를 해결하기 위해 폴리이미드(Polyimide) 기판 위에 인듐 옥사이드와 금 전극을 증착하여 MOSFET 구조의 센서를 제작하였으며 압타머 기반의 표면 기능화를 통해 코티솔과 결합할 수 있는 센싱 물질을 부착하였다.
소자의 성능을 평가하기 위해 다양한 농도의 코티솔 용액을 사용하여 센서의 응답을 확인하였고 150 마이크로미터에서 70 마이크로미터까지의 전극폭에 따라 소자를 설계하여, 농도 및 소자의 전극간격에 따른 응답 특성을 분석하였다. 실험결과 높은 코티솔 농도와 넓은 간격에서 더 많은 전류가 형성되는 것을 확인하였다. 코티솔과 압타머 간의 결합이 소자의 반도체 층에서 캐리어 역할을 하여 드레인 전류가 증가되게 된다. 따라서 더 높은 농도의 코티솔과 더 넓은 전극 간격은 이러한 캐리어의 증가로 이어지게 되므로 고농도-넓은 간격일 때 형성되는 드레인 전류값이 증가하게 된다. 이를 통해 코티솔 농도에 따른 전류 값의 정량화를 통해 더 많은 코티솔의 양을 평가할 수 있음을 확인하였다.
초저농도 (1 nM)에서는 센서의 응답이 계측되지 않아 현 연구에서 최적화된 소자의 검출한계는 10 nM 로 확인하였다. 향후 연구에서 이를 개선할 계획이며 실리콘 기판으로부터 소자를 분리하여 피부 부착 및 실제 체액을 사용한 실험을 통해 소자의 성능을 검증할 예정이다. 본 연구의 결과는 일상에서 실시간으로 스트레스 모니터링을 할 수 있는 코티솔 센서 개발에 기여할 수 있을 것으로 기대한다.
핵심어: 미세전자기계시스템(MEMS), 인듐옥사이드(Indium oxdie), 코티솔(cortisol), 금속 산화막 반도체 전계효과 트랜지스터 (MOSFET)|In this study, we design and optimize the process of a flexible transistor for stress sensing via detecting the stress hormone cortisol. Cortisol is a steroid hormone secreted at the adrenal glands and is called the stress hormone because it is released in response to stress. Cortisol is found in body fluids, and its concentration varies during daily routine. As interest in a healthy lifestyle grows, the importance of stress management has been highlighted. Consequently, the need for accurate stress management has been emphasized. Traditional stress measurement methods rely on subjective assessments or complex equipment for measuring physiological signals, making it difficult to monitor stress in daily environments. To address this, we propose a cortisol-sensing system based on a MOSFET(Metal-Oxide Field Effect Transistor) device. We fabricate a MOSFET-structured sensor by depositing indium oxide and gold electrodes onto a polyimide substrate and coated sensing materials capable of binding with cortisol through aptamer-based surface functionalization. To evaluate the performance of the device, we used cortisol solution at various concentrations and observed the sensor’s response. We designed devices with electrode widths ranging from 150 μm to 70 μm to analyze response characteristics according to cortisol concentration and electrode spacing. The experimental results indicated that higher cortisol concentrations and wider electrode spacing produced higher current levels. The binding between cortisol and the aptamer acts as a carrier in the semiconductor layer of the device leading to an increase 박 경 준. Kyeong Jun Park. Process optimization and design of transfer printed flexible transistor for enhanced cortisol sensing. Department of Robotics and Mechatronics Engineering. 2025. 32p. Advisors Prof. Hoe Joon Ki,. Co-Advisors Prof. Kyung-In Jang. MS/RME 202323004 in drain current. Therefore, higher cortisol concentrations and wider electrode spacing contribute to increased carrier levels resulting in greater drain current at high concentrations and wide spacing. This demonstrates the potential for quantifying cortisol levels through current measurement. At ultra-low concentrations (under 1 nM), the sensor’s response was undetectable, indicating the optimized detection limit of this device as 10 nM. We plan to improve this in future research and will verify the device’s performance by detaching it from the silicon substrate for skin attachment and conducting tests using real biofluids. The outcomes of this study are expected to contribute to the development of cortisol sensors capable of real-time stress monitoring in daily life. Keywords: Microelectromechanical system (MEMS), Indium oxide, cortisol, MOSFET, Process optimizationI. Introduction 1
1.1. Need for stress management 1
1.2. Conventional Stress Measuring Methods 3
1.3. Stress hormone Cortisol and Cortisol based Stress Measuring 5
1.4. Metal-Oxide Semiconductor Field Effect Transistor 7
II. Process Optimization and Sensor Fabrication 9
2.1. Sensor design with interdigitated electrode 9
2.2. Indium oxide deposition optimization 11
2.3. Device fabrication via photolithography process 14
2.4. Surface functionalization for aptamer immobilization 18
III. Sensing Experiment 20
3.1. Sensing mechanism 20
3.2. Experiment setup 22
IV. Results and Discussion 24
4.1. FET characterization 24
4.2. pH sensing result 24
4.3. Cortisol sensing result 27
4.4. Future Works 30
V. Conclusion 31
REFERENCE 32MasterdCollectio
차세대 광전자 응용을 위한 합성과 표면 공학을 통한 콜로이드 양자점 특성 조율
No full textColloidal quantum dots, colloidal synthesis, quantum dot structures, optical properties, ligand exchangeList of Contents
ABSTRACT. i
List of Contents ii
List of Tables v
List of Figures vi
CHAPTER 1. INTRODUCTION 1
1.1. Semiconductors and their impact on human lives 1
1.2. Nanotechnology, Nanoparticles and Nanocrystals (NCs) 2
1.3. History of Discovery and Synthesis of Colloidal Quantum Dots (CQDs) (Zero-
dimensional nanocrystals) 6
1.4. Properties of Quantum Dots 11
1.5. Types of QDs (Core only and core/shell QDs) 15
1.6. Basic Chemistry of Colloidal quantum dots (QDs) Synthesis 18
1.6.1. Role of solvent 19
1.6.2. Importance of the Choice of Precursor 20
1.6.3. Surface Capping ligands 21
1.7. Colloidal Synthesis Techniques 23
1.7.1. Hot injection method: 24
1.7.2. Heating up method: 26
1.7.3. Non-Classical Nucleation 28
1.8. Post Synthesis Treatments 28
1.8.1. Ligand engineering 29
1.9. Quantum Dots Characterization Techniques 31
1.10. Applications of Colloidal Quantum Dots 33
CHAPTER 2. 35
2.1. Importance of Surface Functionalization and Purification for Narrow FWHM and Bright Green-Emitting InP Core–Multishell Quantum Dots via a Two-Step Growth Process 36
2.1.1. Summary of this work 36
2.1.2. Introduction 36
2.1.3. Experimental Section 41
2.1.4. Results and Discussion 48
2.1.5. Conclusion 66
2.2. Colloidal Synthesis of thick-shelled CdSe/ZnS Quantum Dots for Optical Multilevel
Memory 2D-OD Hybrid Inverters 68
2.2.1. Summary 68
2.2.2. Introduction 69
2.2.3. Experimental Method 71
2.2.4. Results and Discussion 73
2.2.5. Conclusion 79
CHAPTER 3. 81
3.1. Insight into sulfur sources on the properties of AgInGaS2 Quantum Dots:
morphology and luminescence 82
3.1.1. Summary 82
3.1.2. Introduction 83
3.1.3. Experimental Procedure 86
3.1.4. Results and Discussion 90
3.1.5. Conclusion 101
CHAPTER 4. 102
4.1. Post-Synthesis Surface Modifications of Colloidal Quantum Dots: (Ligand exchange,
Purification and Photoluminescence Recovery) 103
4.1.1. Summary 103
4.1.2. Introduction 104
4.1.3. Experimental Procedure 107
4.1.4. Results and Discussions 113
4.1.5. Conclusion 130
4.2. References 131
요 약 문 153DoctordCollectio
일주기 리듬을 통한 사회적 행동의 우선 순위 조절의 신경학적 기작
No full textCircadian rhythm, Social prioritization, Suprachiasmatic nucleus, Vasoactive intestinal peptide, Nucleus reuniensⅠ. Introduction 1
1.1 Circadian rhythm 1
1.2 Cell atlas of the SCN 7
1.3 Neural network of the SCN 15
1.4 Circadian organization of behaviors 19
1.5 Circadian organization of social behaviors 21
1.6 Purpose 26
ⅠI. Materials and Methods 27
ⅠII. Results 34
3.1 Circadian profile of social prioritization 34
3.2 The role of SCN VIP neuron and its downstream projection
on circadian rhythm in social prioritization 37
3.3 VIP-VIPR2 signaling in RE is necessary for circadian rhythm
in social prioritization 39
3.4 In vivo responsiveness of RE VIPR2 neuron on circadian time information
and social cues 41
3.5 Optogenetic manipulation of RE VIPR2 neuron and its downstream projection
to mPFC is responsible for circadian rhythm in social prioritization 42
3.6 Behavioral consequences of functional VIPR2 expression in social and
reproductive behavior during naturalistic interaction 43
ⅠV. Discussion 84
V. References 94
VI. Abstract in Korean 107DoctordCollectio
RoPIM: A Processing-in-Memory Architecture for Accelerating Rotary Positional Embedding in Transformer Models
No full textThe emergence of attention-based Transformer models, such as GPT, BERT, and LLaMA, has revolutionized Natural Language Processing (NLP) by significantly improving performance across a wide range of applications. A critical factor driving these improvements is the use of positional embeddings, which are crucial for capturing the contextual relationships between tokens in a sequence. However, current positional embedding methods face challenges, particularly in managing performance overhead for long sequences and effectively capturing relationships between adjacent tokens. In response, Rotary Positional Embedding (RoPE) has emerged as a method that effectively embeds positional information with high accuracy and without necessitating model retraining even with long sequences. Despite its effectiveness, RoPE introduces a considerable performance bottleneck during inference. We observe that RoPE accounts for 61% of GPU execution time due to extensive data movement and execution dependencies. In this paper, we introduce RoPIM, a Processing-In-Memory (PIM) architecture designed to efficiently accelerate RoPE operations in Transformer models. RoPIM achieves this by utilizing a bank-level accelerator that reduces off-chip data movement through in-accelerator support for multiply-addition operations and minimizes operational dependencies via parallel data rearrangement. Additionally, RoPIM proposes an optimized data mapping strategy that leverages both bank-level and row-level mappings to enable parallel execution, eliminate bank-to-bank communication, and reduce DRAM activations. Our experimental results show that RoPIM achieves up to a 307.9× performance improvement and 914.1× energy savings compared to conventional systems. © IEEE.FALSEsciescopu