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Regenerating native surface of lithium-metal electrodes via hydrohalic acid-assisted pre-halogenation
No full textBuilding a uniform and homogeneous solid-electrolyte interphase (SEI) at the initial stage is critical for achieving a long, stable cycling performance in lithium (Li) metal batteries (LMBs). Typically, the majority of Li metal anodes (LMAs) are pre-passivated by inherently heterogeneous native oxide layers, which adversely induce spatially irregular Li+ ion fluxes and sporadic Li dendrite growth, thereby resulting in uncontrollable SEI evolution and poor cycling stability. Although halogenated SEI can offer superior mechanical strength, insulation, and thermodynamic stability, the most suitable Li halides for the halogenation of the LMA surface remain in ongoing debates. This study presents the pre-halogenation of an LMA surface via a simple chemical reaction using hydrohalic acids (HXs, X = F, Cl, Br, and I) dissolved in aprotic solutions. With different halide anions (X−), LiX compounds can be selectively enriched and homogenized on the entire LMA surface. Among the pre-halogenated LMAs (HX-Li), it is experimentally revealed that LiCl-enriched pre-passivation (HCl-Li) can enhance Li electroplating kinetics, facilitating uniform Li nucleation and leading to dendrite-less compact Li plating. HCl-Li effectively mitigates the volume expansion of the reacted Li/SEI layer, leading to longer cycling of the LMBs. © 2024 Elsevier B.V.FALSEsciescopu
피부 연관 단백질(Keratin 17 Tail과 Erythropoietin)의 구조 기능적 특성 및 영향 연구
No full textskin; 피부;wound healing; 상처 회복;structure; 구조;keratin; 케라틴;erythropoietin; 에리트로포이에틴I. Introduction 1
II. Materials and methods 6
1. In vitro 6
1.1 Plasmids 6
1.2 Protein expression 6
1.3 Inclusion Body (IB) prep 7
1.4 Purification of proteins 7
1.5 Reconstitution of Keratin filament 8
1.6 Assessing keratin filament assemblies and binding 8
1.7 Electron microscope of keratin filaments and measurements of filament width 9
2. In vivo 9
2.1 Cell culture 9
2.2 Sample preparation for skin cell proliferation test 10
2.3 Hematoxylin and eosin (H&E) staining 10
2.4 Western blot 10
2.5 Measurement of the melanin amount 11
3. In slico 12
3.1 Complex structure modeling and analysis 12
4. Statistical analysis 12
III. Results 13
1. The K17 tail domain is essential for filament assembly in the K6/K17 pair 13
1.1 Protein purification for experiment 13
1.2 Sedimentation assay of reconstituted keratin pairs 15
1.3 TEM observations of reconstituted keratin pairs 18
1.4 Self-dimerization of K17T affects keratin filament assembly 19
2. EPO-derived peptides affect skin cell proliferation and melanin synthesis 22
2.1 EPOR is expressed in cells that compose the skin 22
2.2 Designing EPO-derived peptides to reduce side effects and modeling their binding structures to EPOR 23
2.3 Effect of EPO-derived peptides on skin cell proliferation and migration 26
2.4 Effects of EPO-derived peptides on melanin synthesis 31
IV. Discussion 34
1. The K17 tail domain is essential for filament assembly in the K6/K17 pair 34
2. EPO-derived peptides affect skin cell proliferation and melanin synthesis 36
V. Conclusion 37
VI. References 38MasterdCollectio
Optimal Handover of Surgical Needle Using Reinforcement Learning for Suturing Automation
No full textSurgery Automation; Suturing Automation; Reinforcement Learning; Deep Q-learning; Autonomous Regrasping; Visual servo control; Robot calibrationⅠ. Introduction 1
1.1 The Necessity of Suturing Automation 1
1.2 Handover Automation Methods 1
1.3.1 Testing in a Real-World Environment 1
1.3.2 Testing in a Real-World Environment 2
1.3.3 Testing in a Real-World Environment · 2
Ⅱ. Surgical robot system 5
2.1 robot system component 5
2.2 Mechanical design 5
2.3 Remote Center of Motion mechanism 8
2.4 Remote Kinematics · 8
Ⅲ. Calibration 11
3.1 RGBD camera calibration · 11
3.2 Robot position control error calibration · 16
Ⅳ. Reinforcement Learning algorithm 17
4.1 Deep Q-Learning algorithm 17
4.2 State definition 20
4.3 Action definition 21
4.4 Reward definition 21
4.5 Model experiment · 22
Ⅴ. Real robot test 26
5.1.1 Task space control 26
5.2.1 Visual Servo control 29
5.2.2 Needle pose estimation 30
5.2.3 Needle grasping using RGBD camera 32
5.2.4 Experimental result · 32
VI. Conclusion · 34MasterdCollectio
REAL-TIME IOT DATA SHARING SYSTEM TO SUPPORT ATTRIBUTE-BASED ACCESS CONTROL AND METHOD OF OPERATION THEREOF
No full text본 개시의 일 실시예에 따른 IoT 장치는 주변 장치를 이용하여 IoT 데이터를 암호화하여 서버에 전송하고, 사용자 장치는 서버에 필요한 IoT 데이터를 요청하여 이를 획득함으로써 실시간 IoT 데이터의 공유가 가능하다. 일 실시 예에서, IoT 장치는 센서를 통해 수집한 IoT 데이터를 암호화하기 위해, 속성 기반 암호화 기법의 비교적 저성능 연산만 수행하고, IoT 장치에게 외부 통신 네트워크 연결을 제공하는 주변 장치에 속성 기반 암호화 기법의 고성능 연산을 포함하는 나머지 단계를 아웃소싱함으로써 최종 암호문을 생성할 수 있다. 일 실시 예에 따른 사용자 장치는 자신의 액세스 정책을 이용하여 속성 블룸 필터를 생성하여, 속성 기반 암호화 기법에 따라 암호화된 IoT 데이터를 요청하여, 이를 획득할 수 있다. 일 실시 예에 따른 클라우드 서버는 IoT 장치 및 주변 장치가 속성 기반 암호화 기법에 따라 암호화한 IoT 데이터를 수신하여 저장하고, 사용자 장치의 요청에 의해 수신한 속성 블룸 필터를 쿼리로 검색되는 IoT 데이터를 해당 사용자 장치에 전송할 수 있다
Unveiling the Nanocluster Conversion Pathway for Highly Monodisperse InAs Colloidal Quantum Dots
No full textColloidal quantum dots (CQDs) have garnered significant attention in nanoscience and technology, with a particular emphasis on achieving high monodispersity in their synthesis. Recent advances in understanding the chemistry of reaction intermediates such as magic-sized nanoclusters (MSC) have paved the way for innovative synthetic strategies. Notably, monodisperse CQDs of various compositions, including indium phosphide, indium arsenide, and cadmium chalcogenide, have been successfully prepared using nanocluster intermediates as single-source precursors. Still, the early stage conversion chemistry of these nanoclusters preceding CQD formation has not been fully unveiled yet. Herein, we report the first-order conversion of amorphous nanoclusters (AMCs) to InAs MSCs prior to the formation of CQDs. We find that MSC, isolated via gel-permeation chromatography, is more stable than purified AMCs, as demonstrated in various chemical and thermolytic reactions. While the surface of InAs AMCs and MSC is similarly bound with carboxylate ligands, detailed structural analyses employing synchrotron X-ray scattering and X-ray absorption spectroscopy unveil subtle distinctions arising from the distinct surface properties and structural disorder characteristics of InAs nanoclusters. We propose that InAs AMCs undergo a surface reduction and structural ordering process, resulting in the formation of an InAs MSC in a thermodynamically local minimum state. Furthermore, we demonstrate that both types of nanoclusters serve as viable precursors, providing a similar monomer supply rate at elevated temperatures of around 300 °C. This study offers invaluable insights into the interplay of structure and chemical stability in binary nanoclusters, enhancing our ability to design these nanoclusters as precursors for highly monodisperse CQDs. © 2024 The Authors. Published by American Chemical Society. This publication is licensed under CC-BY-NC-ND 4.0(https://creativecommons.org/licenses/by-nc-nd/4.0/).TRUEscopu
형상 기억물질을 활용한 줄 꼬임 메커니즘 구동기 연구
No full text형상기억합금(Shape Memory Alloy);줄 꼬임 구동기( Twisted String Actuator);형상 기억( Memory Programming)Ⅰ. INTRODUCTION
Ⅱ. Proof of Concept
2.1 Select Material · 6
2.1.1 Shape Memory Polymer 6
2.1.2 Shape Memory Alloy 9
2.2 Twisting Test · 12
2.2.1 Experiment Setting 12
2.2.2 Twisting Test of TSA 13
2.3 Actuation of TSA with SMA · 20
Ⅲ. Twisted String Actuator with Shape Memory Alloy
3.1 Design Twisted String Actuator with SMA · 25
3.2 Performance Test 31
3.2.1 Hysteresis of TSA with SMA · 13
3.3 Gripper with TSA 33
Ⅳ. Discussion
Ⅴ. Conclusion
ReferencesMasterdCollectio
임의의 비트 단위 계수 추정을 통한 이미지 양자화 복원
No full textImage Processing;Deep Learning;Quantization;Low Level Vision;Implicit Neural NetworkIn today's digital landscape, modern displays and content creation support high bit-depth images and videos, exceeding 8 bits. However, challenges arise when compression codecs reduce bit-depth, resulting in low bit- depth (LBD) images with less than 8 bits, causing artifacts like banding and blurriness. Existing bit depth expansion (BDE) methods fall short of producing satisfactory high bit-depth (HBD) images. To address this, we propose an implicit neural function with a bit query to recover de-quantized images from arbitrarily quantized inputs, aided by a phasor estimator to utilize neighboring pixel information. Our approach outperforms previous BDE methods on natural and animated images and has practical applications, demonstrated effectively on the YouTube UGC dataset, specifically in de-banding scenarios. This research presents a promising solution to enhance image quality in situations of bit-depth reduction. Keywords: Image Dequantization, Quantization, Low-Level Vision, Deep Learning, Implicit Neural Representation|현대 디스플레이와 콘텐츠는 8비트 이상의 이미지와 비디오를 지원한다. 그러나 압축 코덱과 같은 비트 부족 상황은 낮은 비트 깊이 (Low Bit-Depth; LBD) 이미지 (<8비트)에서 밴딩과 흐릿한 아티팩트를 발생시킨다. 이전 비트 깊이 확장 (Bit Depth Expansion; BDE) 방법들은 여전히 만족스럽지 못하고 비트 깊이 (High Bit-Depth; HBD) 이미지를 생성한다. 이를 위해 우리는 임의로 양자화된 입력 이미지에서 비트 좌표를 사용하여 양자화 문제를 해결하는 함축적 신경망 표현법 (Implicit Neural Representation; INR)을 제안한다. 또한, 편각추정기 (Phasor Estimator)를 삽입하여 주변 픽셀의 편각정보를 추정하고 이를 삽입하여 모델의 성능을 상승시킨다. 제안된 방법은 자연 이미지와 애니메이션 이미지에서 이전 BDE 방법에 비해 우수한 성능을 보인다. 또한 제안된 모델을 YouTube-UGC 데이터셋에서 밴딩 제거에 적용한 결과또한 시사한다.I. INTRODUCTION 1
1.1 Introductory Remarks 1
1.2 Bit Depth Expansion 2
1.3 Implicit Neural Representation 4
II. Problem Formulation 8
2.1 Decomposition of Quantized Signal 8
2.2 Binary Vector Space 8
2.3 Application on the Quantized Image 9
III. Method 10
3.1 Arbitrary Bitwise Coeffiients for Dequantization 10
3.2 Phasor Estimator 11
3.3 Bit Decoding 12
IV. Experiment 13
4.1 Network Detail 13
4.1.1 Encoder & Decoder 13
4.1.2 ABCD 13
4.2 Training Strategy 14
4.3 Dataset 14
4.4 Implementation detail 15
V. Results 16
5.1 Qualitative Result 22
5.2 Quantitative Result 27
5.3 Ablation Study 28
5.3.1 Network Components 28
5.3.2 Fixed-bit Training 29
5.4 Phasor Estimation 30
5.5 Debanding 32
5.6 Histogram Analysis 34
VI. Discussion 35
6.1 Phasor Estimator 35
6.2 Artifacts from Encoder 35
6.3 Flops and Memory 36
VII. Conclusion 38
VIII. Future work 39
References 41
국문요약 45MasterdCollectio
Use of olfactory receptor for the inhibition of lactate-induced M2 plarization of tumor-associated macrophages and tumor growth
No full text본 발명은 젖산에 의한 종양 관련 대식세포의 M2형 분화 및 종양 성장의 억제를 위한 후각수용체의 용도에 관한 것으로, 구체적으로, 본 발명자들은 젖산-활성화된 OR Olfr78이 대식세포 젖산 센서로서 기능할 것으로 가정하고, 골수 유래 대식세포(bone marrow derived macrophages; BMDMs) 상의 Olfr78이 종양-유래 젖산을 감지하고, 젖산 유도 M2 분극화를 매개하는지 확인하였다. 대식세포 상에서 젖산 센서로서 Olfr78의 역할에 대한 연구를 위해, 본 발명자들은 Olfr78-/- 마우스를 사용하였다. 또한, 본 발명자들은 종양 조건 배지(tumor conditioned media; TCM)에서 Olfr78에 의해 감지되는 인자들을 확인하고자 하였고, TCM에서 젖산과, 일부 조건에서는 아세트산이 종양 친화적인 M2-TAMs의 Olfr78-매개 생성에 관여하는 주요 인자라는 것을 밝혀냈다. 또한, Olfr78은 TAMs의 젖산-유도 M2 표현형을 매개하는 Gpr132와 이형중합체(heterodimer)를 형성하는 것으로 나타났다. 최종적으로, Olfr78 결핍은 종양 진행 및 전이를 억제시켰고, 생체 내에서(in vivo) 항-종양 면역을 개선한다는 것을 밝혀냈다. 본 발명에 따르면, Olfr78-젖산 상호작용은 종양 진행에 주요 역할을 수행하므로, Olfr78-젖산 축을 표적하는 것은 표적 암 치료에 유용하게 활용될 수 있다
CELLULOSE DERIVATIVE COMPOSITION FOR SECONDARY BATTERY BINDER AND METHOD OF PREPARING COMPOSITION FOR SECONDARY BATTERY ELECTRODE COMPRISING THE SAME
No full textSocial context modulates multibrain broadband dynamics and functional brain-to-brain coupling in the group of mice
Get PDFAlthough mice are social, multiple animals’ neural activities are rarely explored. To characterise the neural activities during multi-brain interaction, we simultaneously recorded local field potentials (LFP) in the prefrontal cortex of four mice. The social context and locomotive states predominately modulated the entire LFP structure. The power of lower frequency bands—delta to alpha—were correlated with each other and anti-correlated with gamma power. The high-to-low-power ratio (HLR) provided a useful measure to understand LFP changes along the change of behavioural and locomotive states. The HLR during huddled conditions was lower than that during non-huddled conditions, dividing the social context into two. Multi-brain analyses of HLR indicated that the mice in the group displayed high cross-correlation. The mice in the group often showed unilateral precedence of HLR by Granger causality analysis, possibly comprising a hierarchical social structure. Overall, this study shows the importance of the social environment in brain dynamics and emphasises the simultaneous multi-brain recordings in social neuroscience.TRUEsciescopu