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텍스트 기반 타겟 중심 스타일 전이 기법
No full textStyle transfer, Text-driven, Image editing, CLIP, Multimodal Model텍스트 입력을 활용하여 객체 중심 수준에서 스타일 전이를 유도하는 새로운 방법인 텍스트 기반 타겟 중심 스타일 전이 기법을 소개합니다. 우리 모델의 핵심은 입력 텍스트와 밀접하게 연관된 정밀한 객체 중심 변환을 위해 세심하게 설계된 패치 단위 공동 방향 (PCD) 손실 함수입니다. 이 손실 함수는 텍스트로 유도된 스타일 방향을 위한 패치 방향 손실과 객체 영역 전반에 걸쳐 균일한 CLIP 임베딩 분포를 유지하는 패치 분포 일관성 손실을 결합합니다. 이를 통해 객체 영역 간에 매끄럽고 조화로운 스타일 전이가 이루어집니다. 또한, 우리의 방법에서 중요한 요소는 텍스트를 통해 객체의 위치를 식별하여 세그멘테이션 마스크의 필요성을 제거하는 텍스트 일치 패치 선택 (TMPS) 모듈과 사전 정의 객체 영역 선택 (PRS) 모듈입니다. 마지막으로, 이미지 배경의 원래 스타일과 구조적 본질을 유지하기 위해 동적으로 식별된 배경 영역에 적용되는 적응형 배경 보존 (ABP) 손실 함수를 도입하였습니다. 광범위한 실험을 통해 우리의 접근 방식이 시각적으로 일관되고 텍스트와 잘 부합하는 스타일 전이 결과를 생성하는 데 효과적임을 입증하였습니다.|We present Text-driven Target-Oriented Style Transfer, a novel method that guides style transfer at an object level using textual inputs. The core of our model is our Patch-wise Co-Directional (PCD) loss, meticulously designed for precise target-oriented transformations that are closely aligned with the input text. This loss combines a patch directional loss for text-guided style direction and a patch distribution consistency loss for even CLIP embedding distribution across object regions. It ensures a seamless and harmonious style transfer across object regions. Key to our method are the Text-Matched Patch Selection (TMPS) and Pre-fixed Region Selection (PRS) modules for identifying object locations via text, eliminating the need for segmentation masks. Lastly, we introduce an Adaptive Background Preservation (ABP) loss to maintain the original style and structural essence of the image’s background. This loss is applied to dynamically identified background areas. Extensive experiments underline the effectiveness of our approach in creating visually coherent and textually aligned style transfers.List of Contents
Abstract --- (i)
List of Contents --- (ii)
List of Tables --- (iii)
List of Figures --- (iii)
I. INTRODUCTION --- (1)
II. RELATED WORKS --- (2)
2.1. Style Transfer --- (2)
2.2. Text-Guided Image Synthesis --- (3)
2.3. Target-oriented Style Transfer --- (3)
III. METHOD --- (4)
3.1. Overview Framework --- (4)
3.2. Text-Matched Patch Selection (TMPS) --- (5)
3.3. Patch-Wise Co-Directional Loss (PCD) --- (7)
3.4. Adaptive Background Preservation Loss (ABP) --- (8)
IV. EXPERIMENTS --- (8)
4.1. Implementation Details --- (8)
4.2. Evaluation metrics --- (9)
4.3. Comparison to state-of-the-arts --- (10)
4.4. Ablation study --- (13)
4.5. Comprehensive Analysis of our method --- (14)
4.6. User study --- (17)
4.7. Limitations --- (17)
4.8. Additional target-oriented style transfer results of our method --- (18)
V. CONCLUSION --- (18)
VI. References --- (23)
VII. 요약문 --- (28)MasterdCollectio
Finite-Temperature Dissipative Quantum Criticality of Resistively Shunted Josephson Junctions via Strong Coupling Expansion
No full textEquilibrium statistical mechanics, Pseudo-particle solver, Phase transition, Resistively shunted Josephson junctionMany studies have been conducted to explain the phase transition of the Josephson junction in the resistive shunted Josephson circuit. However, most of the studies were limited to the case where the temperature condition was 0 K. In particular, it is necessary to introduce a strong correlation study technique when the coupling size of the Josephson junction and the external environment consisting of the RC resonator is large. In this paper, the resistively shunted Josephson circuit was analyzed using a strong coupling expansion technique that considers temperature based on Matsubara’s framework. First, the Hamiltonian of the given circuit was expressed in the form of a matrix using the macroscopic basis state, and the obtained result was substituted into the perturbation-theoretic diagram expansion technique of the partition function. Through the above process, the change of order parameter and spin-spin correlation function was calculated to investigate the state change of the Josephson junction according to the temperature.|저항 분로 조셉션 회로에 대하여 조셉션 접합이 나타내는 상전이를 설명하기 위하여 다양한 연구가 진행되었으나, 대다수의 연구는 온도 조건이 0K 인 경우에 국한되어 있었으며 특히 RC 공진기로 이루어진 외부 환경과 조셉션 접합의 결합의 크기가 큰 경우 강상관계 연구기법을 도입할 필요가 있다. 이 논문에서는 마츠바라 이론을 기반으로 하는 강상관계 풀이기법을 이용해 저항 분로 조셉션 회로를 분석하였다. 먼저 주어진 회로의 해밀토니안을 거시적인 기저상태를 이용하여 행렬의 형태로 나타내었고 얻어진 결과를 분배함수의 섭동론적 다이어그램 전개 기법에 대입하였다. 위 과정을 통해 온도에 따른 조셉션 접합의 상태변화를 알아보기 위하여 질서변수의 기댓값과 소산-변동정리를 기반으로 한 스핀-스핀 상관관계 함수를 계산하였다.1. Introduction 1
2. Methodology 3
2.1 Field operator and Green’s function 3
2.2 Diagrammatic method 4
Diagrammatic expansion of Green’s function 4
Diagrammatic expansion in strong coupling case 5
Evaluation of correlation function 6
3. Model & Application 7
3.1 Circuit model 7
Hamiltonian of resistivity shunted Josephson junction 7
in Josephson phase basis 8
Matrix form of in local eigen basis – 3-level case 9
Matrix form of in local eigen basis – Multilevel case 10
Matrix form of cosΦ in local eigen basis – 3-level case 11
Matrix form of cosΦ in local eigen basis – Multilevel case 11
3.2 Diagrammatic method in the circuit Hamiltonian model 13
Calculation of bosonic action 13
Calculation of Propagator 16
Calculating correlation function 16
4. Numerical calculation for integro-differential equation 19
4.1 Structure of C++ code 19
4.2 Hybridzation function – Simpson’s Rule 20
4.3 Trapezoidal method 21
4.4 Iteration truncation – Relative entropy 23
4.5 Implementation of Correlation function 25
5. Result 28
5.1 Benchmark Setup and Simulation Environment 28
Benchmark: Exact diagonalization in single mode 28
Benchmark: Multi-mode case 29
Benchmark: α = 0 condition· 29
Simulation condition: Saturation test 30
Simulation condition: Size dependence 31
5.2 Orderparameter evaluation 31
Temperature independent result 31
Temperature dependent transition 34
Small alpha 38
5.3 41
Table. 4 condition 41
α in excess range 43
6. Conclusion 46
Conclusion 46
Future work 46
Appendix: Circuit Hamiltonian 47MasterdCollectio
Super-Resolution Angle Estimation Algorithm using Low Complexity MUSIC-Based RELAX for MIMO FMCW Radar
Full text linkA novel super-resolution angle estimation algorithm using low complexity-multiple signal classification (LC-MUSIC)-based relaxation (RELAX) for multiple-input multiple-output (MIMO) frequency-modulated continuous-wave (FMCW) radar is proposed in this paper. FMCW radar is widely used to estimate target location information in various fields, including autonomous driving, defense, and robotics. However, FMCW radar struggles to provide high-resolution direction of arrival (DOA) data. To obtain precise target positions, especially for multiple targets, FMCW radar with high-resolution DOA capability is needed. Conventional FMCW radar employs MIMO-based technology to improve angular resolution because of its low complexity and ease of implementation, but MIMO-based radar still struggles to provide precise angular resolution. To improve the angle resolution, we propose a novel super-resolution DOA algorithm in a MIMO scheme. The new method consists of RELAX-based CLEAN and LC-MUSIC. Combining the MIMO technique with the new super-resolution algorithm enables FMCW radar with high angular resolution to be obtained. To analyze the performance of the proposed estimation, Monte Carlo simulations are performed, and root-mean-square error results are analyzed. Using the FMCW radar module, experiments comparing the proposed and conventional algorithms were performed in an indoor environment. This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. © Copyright The Korean Institute of Electromagnetic Engineering and Science.TRUEsciescopuskcikci_cand
Sulfone-based crystalline organic electrolytes for safe, high energy density solid-state sodium and potassium batteries
No full textSodium batteries, Potassium batteries, Solid-state electrolytes, Crystalline organic electrolytes, Sulfone electrolytes본 논문은 안전하고 고에너지 밀도를 갖춘 고체형 소듐 및 포타슘 배터리를 위한 설폰 화합물 기반의 유기-결정성 고체 전해질 (SCOEs)의 개발을 다룬다. 이 연구는 배터리 기술의 주요 과제인 안전성, 이온 전도도, 안정성 문제를 해결하는 것을 목표로 하였다. 지속 가능하고 효율적인 에너지 저장 시스템에 대한 수요가 증가함에 따라, 소듐 및 포타슘 배터리는 리튬 이온 배터리(LIB)의 유망한 대안으로 주목받고 있지만, 기존 전해질의 가연성, 낮은 이온 전도도, 전극과의 부적합성 같은 한계는 이러한 배터리의 상용화를 저해하고 있다. 본 연구는 설폰 기반 전해질을 통해 고체 배터리 기술을 발전시키고 안전하고 성능이 뛰어난 대안을 제시하였다.
소듐 배터리와 SCOEs
소듐 이온 배터리(SIB)는 풍부하고 널리 분포된 소듐 자원 덕분에 경제적이고 지속 가능한 LIB 대체재로 가능성을 인정받고 있다. 그러나 소듐 배터리는 기존 전해질과 관련된 안전 문제와 성능 한계를 자주 겪는다. 이를 해결하기 위해 본 연구는 디메틸 설폰(DMS) 과 비스(플루오로설포닐)이미드 소듐염(NaFSI)로 구성된 SCOEs를 소개한다. 최적화된 조성(NaFSI/DMS, 2:8 몰비)은 25 °C에서 7.0 × 10−4 S cm−1의 높은 이온 전도도, 그리고 Na⁺/Na 기준 5.5 V 이상의 산화 안정성 등 뛰어난 특성을 보여준다. 또한 이 SCOE는 66 °C의 적절한 융점을 가져, 용융 주조(melt-casting) 공정을 사용할 수 있다. 이 공정은 다공성 복합 전극과 전해질 간의 긴밀한 접촉을 가능하게 하여 고체 배터리의 주요 문제를 해결합니다. SCOE의 성능은 Na3V2(PO4)3 양극과 결합된 소듐 메탈 배터리에서 검증되었다. 기존의 탄산염 기반 액체 전해질과 비교하여, SCOE는 200회 사이클 후에도 91.1% 용량 유지율을 달성하며, 주기 안정성과 용량 유지율이 크게 향상되었다. 또한 SCOE의 난연성은 소듐 배터리의 안전성을 강화하여 강력하고 신뢰할 수 있는 에너지 저장 솔루션이 요구되는 응용 분야에 적합하다.
포타슘 배터리와 SCOEs
포타슘 이온 배터리(KIB)는 자원의 풍부함과 낮은 비용 덕분에 또 다른 LIB 대안으로 떠오르고 있다. 그러나 KIB에 적합한 고체 전해질 개발은 여전히 주요 과제이다. 본 논문은 DMS와 포타슘 비스(플루오로설포닐)이미드(KFSI)로 구성된 SCOEs를 연구하였다. 특정 조성(KFSI/DMS, 1:9 몰비)은 25 °C에서 4.0 × 10⁻⁴ S cm⁻¹의 높은 이온 전도도, 약 5.8 V(K+/K 기준) 의 뛰어난 산화 안정성, 그리고 낮은 가연성을 달성하였다. 소듐 SCOE와 마찬가지로, 포타슘 SCOE도 94 °C의 적절한 융점을 보여 용융 주조 공정을 통해 전극과의 긴밀한 접촉을 보장할 수 있었다. 포타슘 금속 배터리에 SCOE를 도입한 결과, 우수한 사이클 성능과 쿨롬 효율을 보여주었다. 고전압 양극재 KVPO4F 와 KFSI/DMS SCOE를 결합한 포타슘 셀은 100회 사이클 후 88.8% 용량 유지율을 기록했으며, 99.6%의 높은 쿨롬 효율을 유지했다. 이러한 결과는 SCOE가 5 V급 고전압 포타슘 배터리를 가능하게 하고, 고에너지 응용 분야에서 기존 액체 전해질의 한계를 극복할 수 있음을 보여주었다.
자립형 설폰 기반 고체 전해질(FSSE)
SCOE 외에도, 본 연구는 포타슘 배터리에서 프러시안 블루(PB) 양극 사용과 관련된 문제를 해결하기 위해 새로운 자립형 설폰 기반 고체 전해질(FSSE)를 개발하였다. PB 및 유사체는 이온 확산을 용이하게 하는 개방형 구조 덕분에 매력적인 양극 재료로 주목받고 있다. 그러나 고전압 작동 중 PB에서 방출되는 결정수는 부정적인 부반응을 초래하고 용량 저하를 크게 가속한다. KFSI, DMS, 및 UV 경화된 고분자 매트릭스 (ETPTA)로 구성된 FSSE는 결정수 방출을 효과적으로 억제하였다. 또한, 25 °C에서 2.2 × 10−4 S cm−1이온 전도도와 K+/K 기준 약 4.8 V의 산화 안정성을 포함한 바람직한 전해질 특성을 보였다. FSSE를 도입한 포타슘 셀은 200회 사이클 후 74.6% 용량 유지율을 기록했으며, 기존 액체 전해질을 사용한 셀의 53.3%와 비교해 성능이 크게 향상되었다.
핵심 기여와 의의
본 논문은 에너지 저장 분야에 다음과 같은 중요한 기여를 하였다:
1. 혁신적인 전해질 설계: 소듐 및 포타슘 배터리를 위한 SCOE는 기존 액체 전해질보다 안전하고 효율적인 대안을 제공함.
2. 향상된 성능: 높은 이온 전도도, 산화 안정성, 안전성을 갖춘 SCOE와 FSSE는 실온에서 작동 가능한 전고체 배터리의 실현을 가능하게 함.
3. 확장성 및 실용성: 용융 주조 및 폴리머 매트릭스와의 혼용은 상용화를 위한 실질적인 전해질 도입 방법을 제시하며, 미래의 배터리 설계에 새로운 가능성을 제공함.
결론
본 연구는 포스트 리튬 배터리 기술을 발전시키는 데 중요한 진전을 제공하였다. 안전성, 이온 전도도, 전극 호환성이라는 핵심 과제를 해결함으로써, 설폰 화합물 기반의 유기-결정성 고체 전해질은 지속 가능하고 고성능의 소듐 및 포타슘 배터리를 위한 효과적인 해결책을 제시한다. 본 연구 결과는 휴대용 전자기기, 대규모 에너지 저장, 전기 자동차 등 다양한 응용 분야에 걸쳐 광범위한 영향을 미칠 것이다.
핵심어: 소듐 배터리, 포타슘 배터리, 전고체 배터리, 유기-결정성 전해질, 설폰 전해질
|In this study, sulfone based crystalline organic electrolytes (SCOEs) for sodium and potassium batteries have been presented. Their physico-chemical and electrochemical properties will be discussed with various characterizations. Also, their battery application results will be provided. In Chapter 3, SCOEs for sodium batteries were investigated. Owing to their mitigated safety risk and high energy density, all-solid-state sodium batteries are promising post-Li batteries. However, current solid-state electrolytes have insufficient ionic conductivity, electrochemical stability, and contacting ability with porous electrodes. To overcome these issues, this chapter presents SCOEs composed of dimethyl sulfone (DMS) and sodium bis(fluorosulfonyl)imide (NaFSI). One particular SCOE (NaFSI/DMS, 2:8 by mol) has high ionic conductivity (7.0×10−4 S cm−1) at 25 °C and excellent oxidative stability (>5.5 V vs. Na+/Na). Importantly, the SCOE displays an optimum melting point (66 °C), enabling intimate contact with porous composite electrodes via the melt-casting process. NaNa3V2(PO4)3 cells employing this SCOE show better cyclability than do cells employing a conventional carbonate electrolyte (capacity retention 91.1% vs. 60.3% after 200 cycles at 25 °C). Additionally, the SCOE has negligible flammability, unlike carbonate electrolytes, thus holding great promise as an electrolyte for safe, room-temperature operable all-solid-state sodium batteries. In chapter 4 deals with SCOEs for potassium batteries. Solid-state potassium batteries are promising energy storage systems, but their wide use requires suitable solid electrolytes to ensure high ionic conductivity, electrochemical stability, and contacting ability with composite electrodes. For this purpose, this study introduces SCOEs consisting of DMS and potassium bis(fluorosulfonyl)imide (KFSI). One solid-state SCOE, KFSI/DMS 1:9 by mol, exhibits high ionic conductivity (4.0 × 10−4 S cm−1 at 25 °C), oxidation stability (~5.8 V vs. K+/K), Ph.D/ES 201954001 강 석 범. Seokbum Kang. Sulfone-based crystalline organic electrolytes for safe, high energy density solid-state sodium and potassium batteries. Department of Energy Science & Engineering. 2025. 106p. Advisors Prof. Hochun Lee, Co-Advisors Prof. Seung-Tae Hong. and negligible flammability. Moreover, owing to its optimal melting point (94 °C), the SCOE enables seamless contact with the composite electrodes through the melt-casting process, which has been challenging for other solid-state electrolytes. KKVPO4F cells filled with this SCOE show improved cycle performance (capacity retention 88.8% after 100 cycles vs. 77.6% after 74 cycles at 25 °C) with high Coulombic efficiency (asymptotic value 99.6% vs. 92.0%) compared to cells with a conventional carbonate electrolyte. With these results, the developed SCOE paves the way to room-temperature operable, 5 V solid-state potassium batteries. In chapter 5, studies about free-standing sulfone-based solid-state electrolyte (FSSE) for Prussian blue (PB) batteries will be discussed. PB and its analogues are emerging cathode materials for potassium batteries due to their 3D open framework allowing facile ion diffusion. However, 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 FSSE comprising KFSI, DMS, 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. KPB 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. Keywords: Sodium batteries, Potassium batteries, Solid-state batteries, Crystalline organic electrolytes, Sulfone electrolytesI. Introduction 1
II. Literature survey 3
2.1 Sodium batteries 3
2.2 Potassium batteries 6
2.3 Crystalline organic electrolytes (COEs) 9
2.3.1 Introduction 9
2.3.2 Organic ionic plastic crystal electrolytes (OIPCs) 12
2.3.3 Non-ionic plastic crystal electrolytes (NIPCs) 17
2.3.4 Non-plastic crystal electrolytes (NOPCs) 23
III. Sulfone-based crystalline organic electrolyte for safe, room-temperature operable all-solid-state sodium
batteries 33
3.1 Research background 33
3.2 Methods 35
3.3 Results and discussion 40
3.4 Conclusion 52
IV. Sulfone-based crystalline organic electrolyte for 5 V solid-state potassium batteries 22
4.1 Research background 53
4.2 Methods 55
4.3 Results and discussion 58
4.4 Conclusion 70
V. A free-standing sulfone-based solid-state electrolyte mitigating the release of crystal water from the
Prussian blue cathode for high voltage potassium batteries 71
5.1 Research background 71
5.2 Methods 73
5.3 Results and discussion 77
5.4 Conclusion 93
VI. Concluding remark 94
VII. References 97DoctordCollectio
Enhancement of electron transfer efficiency in biofuel cell anodes using biocompatible redox-active ferritin and enzyme assemblies
No full textFerritin, a naturally occurring iron storage protein, plays a critical role in iron oxidation-reduction processes, making it a focus of recent research to improve the performance of biofuel cell (BFC) electrodes. The highly stable FeIII/FeII redox pairs within the ferritin core allow for reversible electron release/uptake during electrochemical sweeps, making it potentially applicable as a biocompatible redox mediator. In addition, the outermost protein nanoshell provides an effective anchoring site for strong bridging with active components. This dual functionality positions ferritin as a promising candidate for improving electron transfer efficiency in BFCs. In this study, we used a spin coating-assisted layer-by-layer assembly approach to construct and investigate multilayer structures composed of ferritin and glucose oxidase, with a particular focus on the redox properties of ferritin and its role in mediating electron transfer between enzymes and electrodes. Our results show that the strategic integration of ferritin into BFC anodes significantly enhances both current density and operational stability, representing a significant advancement in the development of high performance BFCs. The study provides critical insights into the design of stable and efficient BFCs and/or biosensors, highlighting the potential of ferritin-based assemblies to drive future innovations in bioelectrochemical technologies. These advances have significant implications for a wide range of applications, including medical devices, environmental monitoring, and renewable energy systems. © 2025 The Royal Society of Chemistry.FALSEsciescopu
Furan-substituted benzodithiophene-based polymer semiconductors as charge transport materials for organic transistors and nanocrystal photovoltaics
No full textWith the tunability of their electronic properties, it-conjugated polymeric semiconductors have been extensively researched for electronic devices. Here, benzo [1,2-b:4,5-b ']dithiophene-based conjugated polymers are synthesized by controlling the contents of thiophene and furan units and their electrical characteristics are reported. The synthesized furan-containing polymers exhibited smoother surface morphology, desirable solubility, deeper highest occupied molecular orbital levels, increased band gap, and improved film crystallinity. The electrolytegated organic field-effect transistors using 25 % furan substituted polymer, P2, exhibited a high mobility of over 8 cm2 V-1 s-1. Furthermore, AgBiS2 nanocrystal photovoltaics using P2 as a hole transport material provided a higher efficiency of 5.59 % compared to devices using control polymer without furan substitution (4.30 %). Our work demonstrates significant structure-property relationships for modifying the electrical properties of polymer semiconductors using molecular engineering to achieve high-performing organic electronic devices.FALSEsciescopu
An Input Saturation-Tolerant Position Control Method for Magnetic Microrobots Using Adaptive Fuzzy Sliding-Mode Method
No full textThe position control of magnetic medical microrobots is influenced by several environmental uncertainties including the unknown characteristics of the medium and the imaging precision. Furthermore, measuring the physical attributes of the microrobots is a challenging issue. To provide a model-free position control approach for the magnetic medical microrobots, a saturation-tolerant Adaptive Fuzzy Sliding-Mode Control (AFSMC) is designed in this study. In the proposed approach, each control input comprises a fuzzy inference term utilized to approximate an unknown nonlinear function including uncertain forces, a robust part derived to compensate for the fuzzy approximation error and disturbances, and a compensating gain for input saturation. By utilizing the second theorem of Lyapunov and Barbalat’s lemma, it is proved that the closed-loop system is asymptotically stable. The effectuality of the presented controller is assessed by means of two experimental scenarios. The results show that the magnitudes of the tracking errors corresponding to a spiral reference path are less than 0.2 mm at the end of the motion. Moreover, in the test conducted in a 3D printed Aorta phantom, the minimum and the maximum values of the tracking errors are 1.22 mm and 0.95 mm, respectively. —This article introduces an innovative, model-free technique specifically designed to tackle the complex challenges of position control in magnetic medical microrobots. Achieving precise control over these microrobots is a challenging task, compounded by the complexity of accurately measuring their physical properties and the characteristics of their surrounding medium. This challenge is further exacerbated by the issue of input saturation, which can compromise system stability. Our pioneering control method is designed to navigate these obstacles effectively. It functions under the assumption that both the lower and upper saturation limits are unknown, and it eliminates the necessity to model the forces acting on the microrobot. Experimental results confirm the method’s effectiveness in accurately tracking various reference trajectories. These findings suggest that our method holds significant promise for various medical applications. IEEEFALSEsciescopu
Transfer-printed multi-stacked quantum dot color conversion layers for white light-emitting diodes
No full textWhite light-emitting diodes (LEDs) with high efficiency, high color rendering index (CRI), and a wide range of color temperatures are in high demand across diverse lighting and display applications. However, conventional methods, such as coating yellow phosphors onto blue LEDs, often result in low CRI due to insufficient red emission, while the use of mixed phosphors experience efficiency losses from interparticle energy transfer. Herein, we present multi-stacked quantum dot (QD) color conversion layers (CCLs) for white LEDs, fabricated via transfer printing. Our CCLs feature sequentially transfer-printed monochromatic QD layers in various colors, which effectively suppress interparticle energy transfer compared to mixed phosphor configurations. Systematic comparisons reveal that white LEDs with trichromatic QD CCLs achieve high-quality white light with balanced chromaticity (CIE coordinates of 0.33, 0.33) and CRI of 91, surpassing monochromatic and dichromatic CCL configurations. Furthermore, these trichromatic CCLs allow flexible tuning of the correlated color temperature (CCT) from warm white (4260 K) to cool white (6660 K) by adjusting the thickness of the yellow QD layer. Our transfer-printed QD CCLs represent an efficient and adaptable solution for next-generation white LED applications, advancing lighting and display technology toward highly efficient and customizable solutions. © 2024 Elsevier B.V.FALSEsciescopu
Program context-assisted address translation for high-capacity SSDs
No full textAs the capacity of NAND flash-based SSDs keeps increasing, it becomes crucial to design a memory-efficient address translation algorithm that offers high performance when a translation table cannot be entirely loaded in a controller DRAM. Existing flash translation layers (FTL) employ demand-based address translation which caches popular mapping information in DRAM by leveraging locality of I/O references. Owing to the lack of information about detailed behaviors of applications, however, existing demand-based FTLs often suffer from many translation-table misses and thus result in sub-optimal performance. In this paper, we propose a new Program context-AssisteD Flash Translation Layer, called PADFTL. Unlike existing FTLs which are implemented as the form of firmware, PADFTL is vertically integrated with a host-level I/O classifier which provides useful hints for an FTL in an SSD to make a better decision in managing a translation table. The host-level I/O classifier monitors unique behaviors of applications by analyzing their program contexts and categorizes I/O patterns into four types, (1) Loop, (2) Hot, (3) Sequential, and (4) Random, which are then delivered to an SSD through extended interfaces. The SSD-side module of PADFTL partitions a controller DRAM into four zones and isolates mapping information associated with different I/O patterns into separate zones. By employing cache management strategies optimized for individual zones, PADFTL can lower the overall translation-table miss ratio. To evaluate the effectiveness of PADFTL, we implement the host-level classifier in the Linux kernel and PADFTL's FTL in a trace-driven FTL simulator. In our experimental results, compared to the state-of-the-art FTL, PADFTL increases the overall table hit ratio by 16% while reducing the address translation time by up to 20% on average. © 2024FALSEsciescopu
Expressive Whole-Body 3D Gaussian Avatar
No full textFacial expression and hand motions are necessary to express our emotions and interact with the world. Nevertheless, most of the 3D human avatars modeled from a casually captured video only support body motions without facial expressions and hand motions. In this work, we present ExAvatar, an expressive whole-body 3D human avatar learned from a short monocular video. We design ExAvatar as a combination of the whole-body parametric mesh model (SMPL-X) and 3D Gaussian Splatting (3DGS). The main challenges are 1) a limited diversity of facial expressions and poses in the video and 2) the absence of 3D observations, such as 3D scans and RGBD images. The limited diversity in the video makes animations with novel facial expressions and poses non-trivial. In addition, the absence of 3D observations could cause significant ambiguity in human parts that are not observed in the video, which can result in noticeable artifacts under novel motions. To address them, we introduce our hybrid representation of the mesh and 3D Gaussians. Our hybrid representation treats each 3D Gaussian as a vertex on the surface with pre-defined connectivity information (i.e., triangle faces) between them following the mesh topology of SMPL-X. It makes our ExAvatar animatable with novel facial expressions by driven by the facial expression space of SMPL-X. In addition, by using connectivity-based regularizers, we significantly reduce artifacts in novel facial expressions and poses. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2025