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Effective 10-bit OLED driver IC with 11-bit DAC, double capacitor-coupled adder, and offset calibration for enhanced panel driving
No full textIn this paper, we propose an 11-bit source driver IC optimized for high-resolution OLED display driving. The proposed IC adopts a Double Capacitor Coupled Adder (DCCA) structure, which enables parallel execution of the sampling and driving stages, thereby improving temporal efficiency and response speed. Additionally, we introduce a novel Slew Rate Enhancement (SRE) structure that enables rapid response even in conditions with minimal input-output voltage differences, delivering performance well-suited for high-resolution display driving. An Offset Calibration circuit is included to minimize inter-channel voltage discrepancies, ensuring high precision and consistent output performance. Experimental results demonstrate that the proposed IC achieves a short horizontal line time(H) of 2.0 mu s and a slew rate of 9.9 V/mu s. The differential nonlinearity (DNL) and integral nonlinearity (INL) are 0.66 LSB and 0.98 LSB, respectively, and, after Offset Calibration, the maximum inter-channel deviation of output voltage (DVO) is reduced to 2.43 mV.TRUEsciescopu
Simple and High-Throughput Fluorescence Assay Method for DNA Damage Analysis in Single-Stranded DNA-Encoded Library Synthesis
No full textThe fluorescent dye-based simple and high-throughput DNA damage assay method was developed for the single-stranded DNA-encoded library (ssDEL) synthesis. The extent of DNA hybridization between single-stranded DNA (ssDNA) and its complementary DNA is influenced by the damage ratio of ssDNA. This damage can be quantified by measuring the change in the fluorescence of PicoGreen, providing valuable insights into the overall ssDNA integrity and facilitating the screening of DNA-compatible conditions for ssDEL synthesis. The assay performance under various conditions, such as pH, temperature, metal ions, and solvents commonly used in ssDEL synthesis, was evaluated, and the results were cross-checked using high-performance liquid chromatography. While certain conditions have been identified as compatible with double-stranded DNA-encoded library synthesis using headpiece DNA, they may still cause considerable DNA damage during ssDEL synthesis due to the low chemical stability of ssDNA. Given its simplicity and speed, this assay can facilitate high-throughput screening of multiple reaction conditions during the early stages of ssDEL synthesis.FALSEsciescopu
Optical Interferometric Detection Method of Ultrasound Waves for Biomedical Imaging and Non- Destructive Testing
No full textUltrasound technology (UST) is one of the most widely used techniques in non-destructive testing across both industrial and biomedical fields. It offers the advantage of causing no damage to the sample, while still providing high resolution and the ability to measure at greater depths. However, its major limitation lies in the need to use electrical piezo-based transducers (PZT), which require direct contact with the sample. Because of this, UST cannot be used in cases where large surface areas need to be measured, where high temperatures could damage the PZT, where surface contamination must be avoided, or when operator safety is at risk due to the measurement environment. To overcome this limitation, various non-contact ultrasound techniques have been developed. However, most of these systems are large, complex, expensive, and difficult to miniaturize. To address these challenges, this doctoral dissertation proposes a simplified optical interferometry-based system for measuring ultrasound waves. This dissertation consists of six parts: The first chapter introduces the motivation and background of the research. The second chapter presents an interferometer based on a 3×3 optical fiber coupler, and mathematically proves the method for calculating nanometer-scale displacement. The third chapter details the development of a non-contact LUS system based on the 3×3 optical interferometer and demonstrates its ability to measure thickness variations in a PDMS phantom in real time at a single point. The fourth chapter describes the miniaturization of the LUS system’s probe to a few millimeters in diameter and presents results of 2D and 3D scans conducted on PDMS phantoms and biological samples. The fifth chapter applies the system to industrial scenarios, successfully measuring abnormal vibrations caused by equipment malfunctions from a distance of several meters, ensuring operator safety while maintaining high sensitivity. Finally, the sixth chapter provides a comprehensive summary of the research and outlines directions for future work.DoctorAbstract i
Contents ii
List of figures iv
Chapter 1. Introduction 1
1.1. Motivation 1
Chapter 2. 3×3 optical interferometer 3
2.1. Principle of laser ultrasound imaging 3
2.2. Non-contact ultrasound method 6
2.2.1. Air-coupled transducer 6
2.2.2. Bulk interferometer 6
2.2.3. Laser Doppler vibrometer 9
2.2.4. Fiber type interferometer 9
2.3. 3×3 optical interferometer. 12
2.4. Simulation test 17
2.5. The getting parameter using small parts of ellipse 20
2.6. Coherent average 23
Chapter 3. Thickness measurement using LUS 26
3.1. Introduction and motivation 26
3.2. Material and Method 27
3.2.1. Sample preparation 27
3.2.2. Experimental setup 28
3.3. Experimental result 29
3.4. Conclusions and Discussions 36
Chapter 4. Laser Ultrasound Imaging 38
4.1. Introduction and Motivation 38
4.2. Basic Experiment and Reconstruction algorithm 38
4.3. Pulse laser selection 42
4.4. Two-dimensional image from bio samples 45
4.4.1. Cow’s stomach 45
4.4.2. Cow’s Intestine 46
4.5. Three-dimensional reconstruction 49
4.6. Three-dimensional image of PDMS phantom 52
4.7. Three-dimensional image of bio samples 54
4.8. Conclusions and discussions. 56
Chapter 5. Detection of partial discharge occurring in GIS 58
5.1. Introduction and motivation 58
5.2. Basic experiment 62
5.3. System configuration 65
5.4. Displacement analyses caused by partial discharge 67
5.5. Conclusion and Discussion 72
Chapter 6. Conclusions and Future directions 74
6.1. Conclusions 74
6.1. Future directions 76
Reference 78
Chapter 7. Acknowledgement 87
Chapter 8. Curriculum Vitae 8
Early skin seeding regulatory T cells modulate PPARγ-dependent skin pigmentation
No full textThe maintenance of adult tissue homeostasis is dependent on the functional cross-talk between stem cells (SCs) and tissue-resident immune cells. This reciprocal relationship is also essential for tissue organogenesis during early life. The skin harbors a relatively large population of regulatory T cells (Tregs) that accumulate within the first two weeks after birth. A functional role for early skin seeding Tregs (ETregs) during the first week of life is currently unexplored. Here, we show that skin Tregs are detected as early as postnatal day 3 (P3) and enter a dynamic flux of activation marker expression. Punctual ETreg depletion from P6-P8, but not later, resulted in defective hair follicle (HF) melanocyte SC (MeSC) mediated skin pigmentation in juvenile life. Transcriptomic analysis of the whole skin on P9 indicated immediate and pronounced changes in MeSC markers, as well as perturbation of PPARγ target genes in the HF. Accordingly, punctual ETreg depletion, combined with short-term PPARγ antagonization, restored skin pigmentation. Single-cell profilingofP9skinrevealedthatPPARγ signalling activity is preferentially diminished in the HF epithelium upon loss of ETregs. Finally, we explored changes in the single-cell transcriptome of the human tissue disorder, vitiligo, characterized by a lack of melanin and con- sequent skin depigmentation. These analyses showed that the HF cells from lesional vitiligo skin exhibit significant downregulation in PPARγ pathway activation, relative to heathy controls. Overall, ETregs in neonatal skin are critical for sustaining HF PPARγ signaling, which is vital for facilitating MeSC mediated skin pigmentation during postnatal development.TRUEsciescopu
Modeling Consistent Relations between Persona and Response for Persona-based Dialogue
No full textEnsuring persona consistency while maintaining engaging and context-specific interactions is a critical task in persona-based dialogue. However, existing persona-based dialogue datasets lack explicit guidance on how persona sentences relate to the responses. Our analysis using natural language inference (NLI) shows that most persona sentences in these datasets are neutral with respect to the responses, while cases of entailment are occasionally observed and those of contradiction are rare. Such characteristics of these datasets present challenges for dialogue models, making it difficult to effectively capture persona consistency and produce engaging responses.
To address these issues, we propose MoCoRP (Modeling Consistent Relations between Persona and Response), a framework that incorporates explicit relations into the language models. Specifically, we introduce an NLI expert, trained on NLI dataset, to produce explicit NLI relations between persona sentences and response. With the assistance of the NLI expert, the model can reference explicit NLI relations to incorporate appropriate persona information from the context into its responses. We further extend our approach to modern large language models through alignment tuning. Experimental results on the public datasets ConvAI2 and MPChat demonstrate that MoCoRP outperforms existing baselines, achieving superior persona consistency and engaging, context-aware dialogue generation. Furthermore, our model not only excels in quantitative metrics but also shows significant improvements in qualitative aspects, effectively capturing aspects that are challenging to measure by conventional evaluation metrics. These results highlight the effectiveness of explicitly modeling persona-response relations in persona-based dialogue.|페르소나 기반 대화에서 페르소나 일관성을 보장하면서 흥미롭고 맥락에 맞는 대화를 유지하는 것은 중요한 과제입니다. 그러나 기존 페르소나 기반 대화 데이터셋은 페르소나 문장과 응답 간의 관계에 대한 명확한 지침이 부족합니다. 또한, 자연어 추론을 사용하여 이러한 데이터셋을 분석한 결과, 대부분의 페르소나 문장이 응답과 중립적 관계를 가지며, 함의의 경우는 가끔 관찰되지만 모순의 경우는 드뭅니다. 이러한 데이터셋의 특성은 대화 모델에게 도전 과제를 제시하여, 페르소나 일관성을 효과적으로 포착하고 흥미로운 응답을 생성하기 어렵게 만듭니다.
이러한 문제를 해결하기 위해, 우리는 페르소나와 답변 간의 일관된 관계 모델링 (MoCoRP)을 제안합니다. 이는 언어 모델에 명시적인 관계를 통합하는 프레임워크입니다. 구체적으로, 우리는 자연어 추론 데이터셋으로 학습된 자연어 추론 전문가를 도입하여 페르소나 문장과 응답 간의 명시적인 자연어 추론 관계를 생성합니다. 자연어 추론 전문가의 도움을 받아, 모델은 명시적인 자연어 추론 관계를 참조하여 맥락에서 적절한 페르소나 정보를 응답에 통합할 수 있습니다. 또한, 우리는 정렬 튜닝을 통해 최신 대규모 언어 모델에 우리의 접근법을 확장합니다.
공개된 데이터셋인 ConvAI2와 MPChat에서의 실험 결과, MoCoRP는 기존의 베이스라인을 능가하며, 뛰어난 페르소나 일관성과 맥락에 맞는 흥미로운 대화 생성을 달성했음을 보여줍니다. 더 나아가, 우리의 모델은 정량적인 지표에서 우수한 성능을 보였을 뿐만 아니라, 기존의 평가 지표로는 측정하기 어려운 다양한 정성적인 측면에서도 유의미한 향상을 보여주었습니다. 이러한 결과는 페르소나-응답 관계를 명시적으로 모델링하는 접근 방식이 페르소나 기반 대화에서 효과적임을 강조합니다.MasterAbstract (English)
Abstract (Korean)
1 Introduction
2 Related Works
2.1 Persona-based Dialogues
2.2 Natural Language Inference
3 Method
3.1 Task Definition
3.2 MoCoRP
3.2.1 NLI Expert
3.2.2 Relation Learning
3.2.3 Dialogue Learning
3.2.4 Training Objective
3.3 MoCoRP LLM
4 Experiments
4.1 Dataset
4.2 Method for Comparison
4.3 Evaluation Metrics
5 Result
5.1 Conventional Metric Evaluation
5.2 Qualitative Evaluation
5.3 Ablation Study
5.4 Case Study
6 Conclusion
References
A Statistics of Persona-based Dialogue Dataset
B Statistics of Relations
C Implementation Details
Acknowledgement
Identifying the Functional Role of Regulatory T Cell on Alveolar Stem Cell Niche during Lung Tissue Regeneration and Pulmonary Fibrosis
No full textRegulatory T cells (Tregs) play a critical role in modulating inflammation, repair, and fibrosis in lung injury. Using both acute and chronic lung injury models induced by intratracheal bleomycin, we investigated Treg dynamics and their impact on tissue regeneration and fibrosis. In acute lung injury, Tregs (CD4+ Foxp3+ cells) transiently increased during the inflammatory phase and declined during recovery, primarily localizing to tertiary lymphoid structures (TLS). Despite their abundance in TLS, direct interactions between Tregs and alveolar stem cells (AT2 cells) were rare, suggesting a predominantly indirect role in regeneration. In chronic lung injury, Tregs persisted in fibrotic regions, with increased localization to TLS and limited presence in alveolar areas. Using Foxp3-cre;tdTomato and Foxp3iDTR mouse models, we showed that Tregs recruited during inflammation could persist in the tissue when repair was incomplete. Depletion of Tregs exacerbated fibrosis, disrupted alveolar repair, and reduced AT2 cell numbers, highlighting their critical role in maintaining tissue homeostasis. These findings suggest that the dynamics of Tregs are driven by the local microenvironment, with reparative and fibrotic conditions influencing their function and persistence. Persistent Tregs in fibrotic areas may lose their reparative functions or acquire pathological characteristics, contributing to chronic injury. Understanding these dynamics is essential for developing therapeutic strategies targeting Tregs to promote lung repair and mitigate fibrosis.MasterA B S T R A C T ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ⅰ
C O N T E N T S․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ⅱ
L I S T O F F I G U R E S․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ⅳ
Ⅰ. I N T R O D U C T I O N ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ 1
Ⅱ. M A T E R I A L S A N D M E T H O D S ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ 4
1. Mice
2. Bleomycin Administration
3. Lung Tissue Dissociation and Flow Cytometry
4. Lung Tissue Collection & Histology and Immunohistochemistry
Ⅲ. R E S U L T S ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ 7
1. Tregs expressing Il1rl1, a functional receptor for IL-33, dynamically regulate lung injury
repair processes.
2. Treg populations increase during inflammation and decrease during resolution in acute lung injury.
3. The impaired resolution of Treg is observed upon fibrotic lung injury.
4. Tissue-resident Tregs significantly contribute to the repair of lung injuries.
5. The spatial distribution of tissue-resident Tregs plays a critical role in pulmonary fibrosis
progression.
6. Depletion of Tregs impairs alveolar regeneration during lung injury repair.
Ⅳ. D I S C U S S I O N ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ 33
Ⅴ. 국 문 초 록 ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ 37
Ⅵ. R E F E R E N C E S ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ 38
Ⅶ. A C K N O W L E D G E M E N T ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ ․ 4
Grid-Following Factor-based Current Limiting Strategy for a Grid-Forming Inverter with Two Electromotive Forces
No full textThe increasing integration of inverter-based resources (IBRs) poses significant challenges in maintaining frequency and voltage stability in modern power systems. Traditional grid-following (GFL) control lacks inertial support and offers limited adaptability under voltage disturbances. In response, grid-forming (GFM) inverters have been introduced to emulate the behavior of synchronous machines. However, conventional GFM approaches often suffer from inherent coupling among virtual inertia, damping, and droop parameters, and their performance can deteriorate due to the bandwidth limitations of cascaded control structures.
To overcome these limitations, the current-referencing electrified synchronous machine (CURESYM) was proposed. This method employs two separate electromotive forces (EMFs) to independently manage synchronization and current reference tracking. As a result, it provides greater flexibility in tuning dynamic responses without being restricted by inertia and droop parameters. While CURESYM offers promising advantages, it still faces challenges such as overcurrent during faults and the emergence of low-frequency oscillations.
To enhance the performance of CURESYM, this dissertation proposes a novel current-limiting strategy based on a grid-following factor. This factor dynamically modifies the synchronizing EMF during fault events in order to suppress initial current peaks while preserving the GFM characteristics as much as possible. Two methods are proposed for calculating this factor, using current and voltage vectors generated by CURESYM. Furthermore, a synchronization preserving mechanism is developed to ensure accurate frequency tracking under severe current-limiting conditions.
This work also investigates the phenomenon of synchronous resonance (SR) in CURESYM. The source of SR is identified as the voltage difference between the synchronizing EMF and the point-of-connection (PoC) voltage. To mitigate this issue, a virtual resistance adjustment is applied to the admittance model within the EMF generator. This approach improves the damping characteristics of the CURESYM.
The proposed methods are validated through hardware-in-the-loop simulation and laboratory-scale experiments using a 4.4 kVA inverter. The results demonstrate notable improvements in suppressing peak current, mitigating SR, and maintaining synchronization. Through these contributions, the dissertation provides a practical and efficient control framework that enhances the reliability and fault tolerance of GFM inverters in power systems with high IBR penetration.Doctor1. Introduction 1
1. 1. Background 1
1. 2. Research Objectives 5
1. 3. Dissertation Outline 6
2. Previous work: Current-Referencing Electrified Machine 7
2. 1. System description 7
2. 1. 1. Hardware configuration 7
2. 1. 2. Control architecture 9
2. 2. Conventional current-limiting methods 15
2. 3. Summary 20
3. A Grid-Following Factor-Based Current-Limiting Strategy for CURESYM 21
3. 1. Concept of the grid-following factor 21
3. 2. Calculation of the grid-following factor based on vector diagram 26
3. 2. 1. Method 1: Current vector-based calculation 26
3. 2. 2. Method 2: Voltage vector-based calculation 30
3. 3. Preserving synchronization mechanism of CURESYM under current limiting 34
3. 4. Simulation results 36
3. 4. 1. Balanced fault condition 39
3. 4. 2. Unbalanced fault condition 45
3. 4. 3. Frequency deviation 48
3. 5. Summary 51
4. Mitigation of Synchronous Resonance in CURESYM through Admittance Adjustment 53
4. 1. Cause of synchronous resonance in CURESYM 53
4. 2. Mitigation of SR via virtual admittance adjustment in CURESYM 58
4. 3. Summary 71
5. Hardware-in-the-loop Simulation and Experimental Results 72
5. 1. Real-time HIL simulation setup 72
5. 2. HIL simulation results 73
5. 2. 1. Balanced fault in strong grid 73
5. 2. 2. Unbalanced fault in strong grid 78
5. 2. 3. Frequency deviation in strong grid 81
5. 3. Experimental setup 85
5. 4. Experimental results 88
5. 4. 1. Balanced fault in weak grid 88
5. 4. 2. Unbalanced fault in weak grid 91
5. 4. 3. Frequency deviation in weak grid 94
5. 5. Summary 97
6. Conclusion and Future works 99
6. 1. Summary 99
6. 2. Future works 100
Bibliography 102
Acknowledgement
Curriculum Vita
Global Funnel Control of Nonlinear Systems with Unknown and Time-Varying Fractional Powers
No full textThis paper is concerned with the global funnel control (FC) issue of the nonlinear systems with unknown dynamics and time-varying fractional powers. An FC strategy is proposed in this paper, not only the barrier functions but also the tracking and intermediate errors are introduced to our control law in a proportional feedback way, which not only guarantees uniform performance insurance under any initial condition of the control system but also leads to about 50% reduction in control amplitude with respect to the existing solutions. Moreover, it exhibits notable simplicity, with no need for parametric details of time-varying fractional powers, adding a power integrator technique, parameter identification, function approximation or derivative calculation. A comparative simulation demonstrates the effectiveness and superiority of the developed method. © 2025 Elsevier B.V., All rights reserved.TRUEsciescopu