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Technical roadmap of ultra-thin crystalline silicon-based bioelectronics
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作者 Mingyu Sang Kyubeen Kim +3 位作者 Doohyun J Lee Young Uk Cho Jung Woo Lee Ki Jun Yu 《International Journal of Extreme Manufacturing》 2025年第5期211-260,共50页
Ultra-thin crystalline silicon stands as a cornerstone material in the foundation of modern micro and nano electronics.Despite the proliferation of various materials including oxide-based,polymer-based,carbon-based,an... Ultra-thin crystalline silicon stands as a cornerstone material in the foundation of modern micro and nano electronics.Despite the proliferation of various materials including oxide-based,polymer-based,carbon-based,and two-dimensional(2D)materials,crystal silicon continues to maintain its stronghold,owing to its superior functionality,scalability,stability,reliability,and uniformity.Nonetheless,the inherent rigidity of the bulk silicon leads to incompatibility with soft tissues,hindering the utilization amid biomedical applications.Because of such issues,decades of research have enabled successful utilization of various techniques to precisely control the thickness and morphology of silicon layers at the scale of several nanometres.This review provides a comprehensive exploration on the features of ultra-thin single crystalline silicon as a semiconducting material,and its role especially among the frontier of advanced bioelectronics.Key processes that enable the transition of rigid silicon to flexible form factors are exhibited,in accordance with their chronological sequence.The inspected stages span both prior and subsequent to transferring the silicon membrane,categorized respectively as on-wafer manufacturing and rigid-to-soft integration.Extensive guidelines to unlock the full potential of flexible electronics are provided through ordered analysis of each manufacturing procedure,the latest findings of biomedical applications,along with practical perspectives for researchers and manufacturers. 展开更多
关键词 crystalline silicon OXIDATION DOPING transfer process flexible bioelectronics
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Chemical exchange saturation transfer MRI for neurodegenerative diseases:An update on clinical and preclinical studies
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作者 Ahelijiang Saiyisan Shihao Zeng +4 位作者 Huabin Zhang Ziyan Wang Jiawen Wang Pei Cai Jianpan Huang 《Neural Regeneration Research》 2026年第2期553-568,共16页
Chemical exchange saturation transfer magnetic resonance imaging is an advanced imaging technique that enables the detection of compounds at low concentrations with high sensitivity and spatial resolution and has been... Chemical exchange saturation transfer magnetic resonance imaging is an advanced imaging technique that enables the detection of compounds at low concentrations with high sensitivity and spatial resolution and has been extensively studied for diagnosing malignancy and stroke.In recent years,the emerging exploration of chemical exchange saturation transfer magnetic resonance imaging for detecting pathological changes in neurodegenerative diseases has opened up new possibilities for early detection and repetitive scans without ionizing radiation.This review serves as an overview of chemical exchange saturation transfer magnetic resonance imaging with detailed information on contrast mechanisms and processing methods and summarizes recent developments in both clinical and preclinical studies of chemical exchange saturation transfer magnetic resonance imaging for Alzheimer’s disease,Parkinson’s disease,multiple sclerosis,and Huntington’s disease.A comprehensive literature search was conducted using databases such as PubMed and Google Scholar,focusing on peer-reviewed articles from the past 15 years relevant to clinical and preclinical applications.The findings suggest that chemical exchange saturation transfer magnetic resonance imaging has the potential to detect molecular changes and altered metabolism,which may aid in early diagnosis and assessment of the severity of neurodegenerative diseases.Although promising results have been observed in selected clinical and preclinical trials,further validations are needed to evaluate their clinical value.When combined with other imaging modalities and advanced analytical methods,chemical exchange saturation transfer magnetic resonance imaging shows potential as an in vivo biomarker,enhancing the understanding of neuropathological mechanisms in neurodegenerative diseases. 展开更多
关键词 Alzheimer’s disease chemical exchange saturation transfer Huntington’s disease magnetic resonance imaging molecular imaging multiple sclerosis neurodegenerative disease Parkinson’s disease
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Refractive Index and Electronic Polarizability of Ternary Chalcopyrite Semiconductors 被引量:2
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作者 KUMAR V. SINHA Anita +2 位作者 SINGH B.P. SINHA A.P. JHA V. 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第12期147-151,共5页
Simple models are proposed for the calculation of refractive index n and electronic polarizability α of AⅠBⅢC2Ⅵ and AⅡBⅣC2Ⅴ compounds of groups of chalcopyrite semiconductors from their energy gap data. The val... Simple models are proposed for the calculation of refractive index n and electronic polarizability α of AⅠBⅢC2Ⅵ and AⅡBⅣC2Ⅴ compounds of groups of chalcopyrite semiconductors from their energy gap data. The values family and 12 compounds of AⅡBⅣC2Ⅴ family are calculated for the work. The proposed models are applicable for the whole range of energy gap materials. The calculated values are compared with the available experimental and reported values. A fairly good agreement between them is obtained. 展开更多
关键词 TE In Refractive Index and Electronic Polarizability of Ternary Chalcopyrite Semiconductors
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Influence of an Electronic Field on the GMI Effect of Fe-based Nanocrystalline Microwire 被引量:2
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作者 Q.Zhang D.L.Chen +3 位作者 X.Li P.X.Yang J.H.Chu Z.J.Zhao 《Nano-Micro Letters》 SCIE EI CAS 2013年第1期13-17,共5页
In this work, a Fe-based nanocrystalline microwire of 20 mm in length and 25 μm in diameter was placed in the center of a 316 stainless steel pipe. The pipe was 500 μm in diameter and a little shorter than the micro... In this work, a Fe-based nanocrystalline microwire of 20 mm in length and 25 μm in diameter was placed in the center of a 316 stainless steel pipe. The pipe was 500 μm in diameter and a little shorter than the microwire. A series of voltages were applied on the pipe to study the influence of the electrical field on the Giant-Magneto-Impedance(GMI) effect of the microwire. Experimental results showed that the electronic field between the wire and the pipe reduced the hysteresis of the GMI effect. The results were explained based on equivalent circuit and eddy current consumptions analysis. 展开更多
关键词 GMI Eddy consumptions Electronic field Equivalent circuit
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Vertically Integrated Electronics: New Opportunities from Emerging Materials and Devices 被引量:2
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作者 Seongjae Kim Juhyung Seo +1 位作者 Junhwan Choi Hocheon Yoo 《Nano-Micro Letters》 SCIE EI CAS CSCD 2022年第12期195-223,共29页
Vertical three-dimensional(3D)integration is a highly attractive strategy to integrate a large number of transistor devices per unit area.This approach has emerged to accommodate the higher demand of data processing c... Vertical three-dimensional(3D)integration is a highly attractive strategy to integrate a large number of transistor devices per unit area.This approach has emerged to accommodate the higher demand of data processing capability and to circumvent the scaling limitation.A huge number of research efforts have been attempted to demonstrate vertically stacked electronics in the last two decades.In this review,we revisit materials and devices for the vertically integrated electronics with an emphasis on the emerging semiconductor materials that can be processable by bottom-up fabrication methods,which are suitable for future flexible and wearable electronics.The vertically stacked integrated circuits are reviewed based on the semiconductor materials:organic semiconductors,carbon nanotubes,metal oxide semiconductors,and atomically thin two-dimensional materials including transi-tion metal dichalcogenides.The features,device performance,and fabrication methods for 3D integration of the transistor based on each semiconductor are discussed.Moreover,we highlight recent advances that can be important milestones in the vertically integrated elec-tronics including advanced integrated circuits,sensors,and display systems.There are remaining challenges to overcome;however,we believe that the vertical 3D integration based on emerging semiconductor materials and devices can be a promising strategy for future electronics. 展开更多
关键词 Vertical stacking Three-dimensional integration Metal routing Via-hole Two-dimensional semiconductors
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Prediction of sepsis within 24 hours at the triage stage in emergency departments using machine learning 被引量:3
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作者 Jingyuan Xie Jiandong Gao +8 位作者 Mutian Yang Ting Zhang Yecheng Liu Yutong Chen Zetong Liu Qimin Mei Zhimao Li Huadong Zhu Ji Wu 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2024年第5期379-385,共7页
BACKGROUND:Sepsis is one of the main causes of mortality in intensive care units(ICUs).Early prediction is critical for reducing injury.As approximately 36%of sepsis occur within 24 h after emergency department(ED)adm... BACKGROUND:Sepsis is one of the main causes of mortality in intensive care units(ICUs).Early prediction is critical for reducing injury.As approximately 36%of sepsis occur within 24 h after emergency department(ED)admission in Medical Information Mart for Intensive Care(MIMIC-IV),a prediction system for the ED triage stage would be helpful.Previous methods such as the quick Sequential Organ Failure Assessment(qSOFA)are more suitable for screening than for prediction in the ED,and we aimed to fi nd a light-weight,convenient prediction method through machine learning.METHODS:We accessed the MIMIC-IV for sepsis patient data in the EDs.Our dataset comprised demographic information,vital signs,and synthetic features.Extreme Gradient Boosting(XGBoost)was used to predict the risk of developing sepsis within 24 h after ED admission.Additionally,SHapley Additive exPlanations(SHAP)was employed to provide a comprehensive interpretation of the model's results.Ten percent of the patients were randomly selected as the testing set,while the remaining patients were used for training with 10-fold cross-validation.RESULTS:For 10-fold cross-validation on 14,957 samples,we reached an accuracy of 84.1%±0.3%and an area under the receiver operating characteristic(ROC)curve of 0.92±0.02.The model achieved similar performance on the testing set of 1,662 patients.SHAP values showed that the fi ve most important features were acuity,arrival transportation,age,shock index,and respiratory rate.CONCLUSION:Machine learning models such as XGBoost may be used for sepsis prediction using only a small amount of data conveniently collected in the ED triage stage.This may help reduce workload in the ED and warn medical workers against the risk of sepsis in advance. 展开更多
关键词 SEPSIS Machine learning Emergency department TRIAGE Informatics
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10 Gb/s Optical Interconnection on Flexible Optical Waveguide in Electronic Printed Circuit Board 被引量:2
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作者 Shih-Hsiang Hsu Chih-Yuan Tsou +1 位作者 Chih-Ming Wang Sheng-Chieh Tseng 《Optics and Photonics Journal》 2013年第2期252-255,共4页
In this paper, we proposed 10 Gb/s transmission using 4-channel polymer waveguides on the optical electronic printed circuit board. It was simulated by the ray tracing method for tolerance study of optical interconnec... In this paper, we proposed 10 Gb/s transmission using 4-channel polymer waveguides on the optical electronic printed circuit board. It was simulated by the ray tracing method for tolerance study of optical interconnection and fabrication. In order for easy fabrication and high position accuracy, the polymer waveguides were forming silver coated 45° reflective mirrors by dicing method and e-beam deposition for 90° light beam turning. The coupling loss was demonstrated in different polishing grit sizes. The optical interconnection in board-embed 4-channel flexible waveguides was demonstrated with a low propagation loss of 0.1 dB/cm and a clear eye diagram at 2.5 Gb/s data rate per channel. 展开更多
关键词 FLEXIBLE WAVEGUIDE Optical ELECTRONIC PRINTED Circuit BOARD
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Electronic mobility in the high-carrier-density limit of ion gel gated IDTBT thin film transistors 被引量:1
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作者 包蓓 邵宪一 +9 位作者 谭璐 王文河 吴越珅 文理斌 赵家庆 唐伟 张为民 郭小军 王顺 刘荧 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第9期20-24,共5页
Indacenodithiophene-co-benzothiadiazole(IDTBT) has emerged as one of the most exciting semiconducting polymers in recent years because of its high electronic mobility and charge transport along the polymer backbone.... Indacenodithiophene-co-benzothiadiazole(IDTBT) has emerged as one of the most exciting semiconducting polymers in recent years because of its high electronic mobility and charge transport along the polymer backbone. By using the recently developed ion gel gating technique we studied the charge transport of IDTBT at carrier densities up to 10^21cm^-3.While the conductivity in IDTBT was found to be enhanced by nearly six orders of magnitude by ionic gating, the charge transport in IDTBT was found to remain 3D Mott variable range hopping even down to the lowest temperature of our measurements, 12 K. The maximum mobility was found to be around 0.2 cm^2·V^-1·s^-1, lower than that of Cytop gated field effect transistors reported previously. We attribute the lower mobility to the additional disorder induced by the ionic gating. 展开更多
关键词 semiconducting polymer ion gel gating charge transport variable range hopping
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Tailoring Classical Conditioning Behavior in TiO_(2) Nanowires:ZnO QDs-Based Optoelectronic Memristors for Neuromorphic Hardware 被引量:1
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作者 Wenxiao Wang Yaqi Wang +5 位作者 Feifei Yin Hongsen Niu Young-Kee Shin Yang Li Eun-Seong Kim Nam-Young Kim 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第7期265-280,共16页
Neuromorphic hardware equipped with associative learn-ing capabilities presents fascinating applications in the next generation of artificial intelligence.However,research into synaptic devices exhibiting complex asso... Neuromorphic hardware equipped with associative learn-ing capabilities presents fascinating applications in the next generation of artificial intelligence.However,research into synaptic devices exhibiting complex associative learning behaviors is still nascent.Here,an optoelec-tronic memristor based on Ag/TiO_(2) Nanowires:ZnO Quantum dots/FTO was proposed and constructed to emulate the biological associative learning behaviors.Effective implementation of synaptic behaviors,including long and short-term plasticity,and learning-forgetting-relearning behaviors,were achieved in the device through the application of light and electrical stimuli.Leveraging the optoelectronic co-modulated characteristics,a simulation of neuromorphic computing was conducted,resulting in a handwriting digit recognition accuracy of 88.9%.Furthermore,a 3×7 memristor array was constructed,confirming its application in artificial visual memory.Most importantly,complex biological associative learning behaviors were emulated by mapping the light and electrical stimuli into conditioned and unconditioned stimuli,respectively.After training through associative pairs,reflexes could be triggered solely using light stimuli.Comprehen-sively,under specific optoelectronic signal applications,the four features of classical conditioning,namely acquisition,extinction,recovery,and generalization,were elegantly emulated.This work provides an optoelectronic memristor with associative behavior capabilities,offering a pathway for advancing brain-machine interfaces,autonomous robots,and machine self-learning in the future. 展开更多
关键词 Artificial intelligence Classical conditioning Neuromorphic computing Artificial visual memory Optoelectronic memristors ZnO Quantum dots
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Deep InP Gratings for Opto-Electronic Devices Etched by C12/CH4/Ar Inductively Coupled Plasma 被引量:1
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作者 王健 田建柏 +3 位作者 熊兵 孙长征 郝智彪 罗毅 《Chinese Physics Letters》 SCIE CAS CSCD 2006年第8期2158-2160,共3页
Deep InP gratings are etched by C12/CH4/Ar inductively coupled plasma (ICP) at room temperature. A comparison is made between SiNz mask patterns formed by wet and dry etching. SF6 reactive ion etching is adopted for... Deep InP gratings are etched by C12/CH4/Ar inductively coupled plasma (ICP) at room temperature. A comparison is made between SiNz mask patterns formed by wet and dry etching. SF6 reactive ion etching is adopted for smooth and vertical sidewall. The etching conditions of C12/CH4/Ar ICP are optimized for high anisotropy, and a 1.7-μm-deep InP grating with an aspect ratio of 10:1 is demonstrated. The technique is then used for the fabrication of 1.55-μm laterally coupled distributed feedback A1GMnAs-InP laser. 展开更多
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Electronic Nose Technology Based on Quantum Dot Filters
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作者 Zhenan Li Jie Bao 《Optics and Photonics Journal》 2017年第8期26-32,共7页
The electronic nose with chemical dyes as sensor can react with target gas and have specific color changes. In general, RGB camera collects a group of images to record these changes used for pattern recognition. RGB f... The electronic nose with chemical dyes as sensor can react with target gas and have specific color changes. In general, RGB camera collects a group of images to record these changes used for pattern recognition. RGB filters are not sensitive to the slight color changes, which limits the performance of this kind of electronic nose. This paper demonstrates using quantum dot spec-troscopy technology to solve this problem. Multiple quantum dot filters are placed on the surface of image sensor. When capturing images, there are more response channels of the same incident light than RGB filters. Simulation and experiment both prove that quantum dot filters with appropriate processing are more sensitive to color changes than RGB filters. 展开更多
关键词 QUANTUM DOTS SPECTRUM RGB FILTERS Pattern Recognition
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A novel contact engineering method for transistors based on two-dimensional materials
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作者 Yaochen Sheng LuFang Zhang +9 位作者 Feng Li Xinyu Chen Zhijian Xie Haiyan Nan Zihan Xu David Wei Zhan Jianhao Chen Yong Pu Shaoqing Xiao Wenzhong Bao 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2021年第10期15-19,共5页
Contact engineering is of critical importance for two-dimensional(2D)transition metal dichalcogenide(TMD)-based devices.However,there are only a few solutions to overcome this obstacle because of the complexity of the... Contact engineering is of critical importance for two-dimensional(2D)transition metal dichalcogenide(TMD)-based devices.However,there are only a few solutions to overcome this obstacle because of the complexity of the TMD-contact interface.In this work,we propose a novel method using a soft plasma treatment followed by the seamless deposition of a metal electrode to reduce the contact resistance of MoS_(2)field effect transistors(FETs).The treated FETs exhibit three times higher mobility than the control FETs without plasma treatment.The soft plasma treatment can remove the facial sulfur atoms and expose the middle Mo atoms so that they come into direct contact with the metal electrode,thus greatly improving the contact behavior.First-principles calculation is also performed to support the experimental results.Our potentially scalable strategy can be extended to the whole family of TMD based FETs to provide a possible route of device processsing technology for 2D device application. 展开更多
关键词 Electrical contact resistance MoS_(2) PLASMA
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Electronically Tunable Minimum Component Biquadratic Filters for Interface Circuits
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作者 Mehmet Sagbas 《Circuits and Systems》 2011年第3期237-241,共5页
In this paper, two new electronically tunable filter configurations are proposed. The proposed filters operate current-mode (CM), voltage-mode (VM), transimpedance-mode (TIM) and transadmittance-mode (TAM). The first ... In this paper, two new electronically tunable filter configurations are proposed. The proposed filters operate current-mode (CM), voltage-mode (VM), transimpedance-mode (TIM) and transadmittance-mode (TAM). The first configuration realizes second-order VM band-pass and TAM high-pass filter characteristics from the same configuration. The second one realizes second-order TIM band-pass and CM low-pass filter characteristics from the same configuration. They also use minimum number of electronic components (two capacitors and one active component namely;current controlled current difference transconductance amplifier). The workability of the proposed structures has been demonstrated by simulation results. 展开更多
关键词 Second-Order Filters CC-CDBA Electronic Tunability Current-Mode Circuits Interface Circuits
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Self-mode-locking optoelectronic oscillator with ultrashort time delay
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作者 Hao Chen Shifeng Liu +6 位作者 Tongtong Xie Qingshui Guo Qiuyi Shen Chen Zhu Daru Chen Hongyan Fu Shilong Pan 《Advanced Photonics Nexus》 2024年第4期58-69,共12页
The optoelectronic oscillator(OEO)is a typical time-delay system with rich nonlinear dynamical characteristics.Most of the previous research on OEOs has been focused on analyzing the properties of OEOs with a long tim... The optoelectronic oscillator(OEO)is a typical time-delay system with rich nonlinear dynamical characteristics.Most of the previous research on OEOs has been focused on analyzing the properties of OEOs with a long time delay,which makes it difficult to realize mode locking without additional phaselocking mechanisms.We have achieved,for the first time to our knowledge,a self-mode-locking OEO and generated stable microwave frequency combs by analyzing the characteristics of OEOs with an ultrashort time scale.In the experiment,the self-mode-locking OEOs with fundamental mode,second-order harmonic,and sixth-order harmonic were realized by adjusting the system parameters,all of which produced uniform square wave signals with tunable duty cycles,steep rising and falling edges,and periods of less than 20 ns.The self-fundamental-mode-locking OEOs with different time delays were also implemented and experimentally realized.Furthermore,the experiment revealed the self-hybrid mode-locking OEO,which is the coexistence and synchronization of the three measured self-locking modes in one OEO cavity,demonstrating the complex nonlinear dynamical behaviors of the OEO system and enabling the generation of periodic nonuniform hybrid square wave signals.The realization of the self-mode-locking OEO and the generation of flexible and stable square wave signals at ultrashort time scales enrich the study of OEO nonlinear dynamics in the realm of complex microwave waveform generation,offering promising applications in areas such as atomic clocks,radars,communications,and optoelectronic neural networks. 展开更多
关键词 optoelectronic oscillator self-mode locking microwave frequency combs square wave signal
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High-efficiency RGB achromatic liquid crystal diffractive optical elements 被引量:1
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作者 Yuqiang Ding Xiaojin Huang +2 位作者 Yongziyan Ma Yan Li Shin-Tson Wu 《Opto-Electronic Advances》 2025年第3期4-15,共12页
Liquid crystal Pacharatnam-Berry phase optical elements(PBOEs)have found promising applications in augmented reality and virtual reality because of their slim formfactor,lightweight,and high optical efficiency.However... Liquid crystal Pacharatnam-Berry phase optical elements(PBOEs)have found promising applications in augmented reality and virtual reality because of their slim formfactor,lightweight,and high optical efficiency.However,chromatic aberration remains a serious longstanding problem for diffractive optics,hindering their broader adoption.To overcome the chromatic aberrations for red,green and blue(RGB)light sources,in this paper,we propose a counterintuitive multi-twist structure to achieve narrowband PBOEs without crosstalk,which plays a vital role to eliminate the chromatic aberration.The performance of our designed and fabricated narrowband Pacharatnam-Berry lenses(PBLs)aligns well with our simulation results.Furthermore,in a feasibility demonstration experiment using a laser projector,our proposed PBL system indeed exhibits a diminished chromatic aberration as compared to a broadband PBL.Additionally,polarization raytracing is implemented to demonstrate the versatility of the multi-twist structure for designing any RGB wavelengths with high contrast ratios.This analysis explores the feasibility of using RGB laser lines and quantum dot light-emitting diodes.Overall,our approach enables high optical efficiency,low fabrication complexity,and high degree of design freedom to accommodate any liquid crystal material and RGB light sources,holding immense potential for widespread applications of achromatic PBOEs. 展开更多
关键词 achromatic diffractive optical elements Pacharatnam-Berry phase optical elements liquid crystal planar optics near-eye displays
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利用Zn掺杂制备高效稳定工业级电解水的NiBP微球催化剂研究
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作者 Sumiya Akter Dristy Md Ahasan Habib +5 位作者 Shusen Lin Mehedi Hasan Joni Rutuja Mandavkar Young-Uk Chung Md Najibullah Jihoon Lee 《物理化学学报》 北大核心 2025年第7期125-138,共14页
在未来的能源系统中,绿氢具有巨大的应用潜力。设计非贵金属电催化剂对于电解水制氢至关重要,尤其是对于工业级电流密度电解水的实际应用。本文通过水热和电化学方法以及焙烧相结合的多步制备方法,制备得到Zn掺杂的NiBP微球电催化剂(Zn/... 在未来的能源系统中,绿氢具有巨大的应用潜力。设计非贵金属电催化剂对于电解水制氢至关重要,尤其是对于工业级电流密度电解水的实际应用。本文通过水热和电化学方法以及焙烧相结合的多步制备方法,制备得到Zn掺杂的NiBP微球电催化剂(Zn/NiBP)。该催化剂在1 mol·L^(−1)KOH电解质溶液中,电流密度为100 mA·cm^(−2),析氢反应(HER)和析氧反应(OER)的过电位分别为95 mV和280 mV,性能优于之前报道的大多数催化剂。当Zn/NiBP为双功能的阴极和阳极催化剂,在1 mol·L^(−1)KOH溶液中,电流密度达到2000 mA·cm^(−2),电解电压为3.10 V,优于Pt/C||RuO_(2)催化剂体系的电解性能。对于Pt/C||Zn/NiBP组成的电解池体系,在1和6 mol·L^(−1)KOH中,当电解电流密度达到2000 mA·cm^(−2)时,电解电压分别仅为2.50和2.30 V,表明该催化剂在实际的工业条件下具有优异的电解水性能。 展开更多
关键词 高电流 锌掺杂 产氢 电催化剂 混合电催化剂
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A Rapid Adaptation Approach for Dynamic Air‑Writing Recognition Using Wearable Wristbands with Self‑Supervised Contrastive Learning
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作者 Yunjian Guo Kunpeng Li +4 位作者 Wei Yue Nam‑Young Kim Yang Li Guozhen Shen Jong‑Chul Lee 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期417-431,共15页
Wearable wristband systems leverage deep learning to revolutionize hand gesture recognition in daily activities.Unlike existing approaches that often focus on static gestures and require extensive labeled data,the pro... Wearable wristband systems leverage deep learning to revolutionize hand gesture recognition in daily activities.Unlike existing approaches that often focus on static gestures and require extensive labeled data,the proposed wearable wristband with selfsupervised contrastive learning excels at dynamic motion tracking and adapts rapidly across multiple scenarios.It features a four-channel sensing array composed of an ionic hydrogel with hierarchical microcone structures and ultrathin flexible electrodes,resulting in high-sensitivity capacitance output.Through wireless transmission from a Wi-Fi module,the proposed algorithm learns latent features from the unlabeled signals of random wrist movements.Remarkably,only few-shot labeled data are sufficient for fine-tuning the model,enabling rapid adaptation to various tasks.The system achieves a high accuracy of 94.9%in different scenarios,including the prediction of eight-direction commands,and air-writing of all numbers and letters.The proposed method facilitates smooth transitions between multiple tasks without the need for modifying the structure or undergoing extensive task-specific training.Its utility has been further extended to enhance human–machine interaction over digital platforms,such as game controls,calculators,and three-language login systems,offering users a natural and intuitive way of communication. 展开更多
关键词 Wearable wristband Self-supervised contrastive learning Dynamic gesture Air-writing Human-machine interaction
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A close look at few-shot real image super-resolution from the distortion relation perspective
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作者 Xin Li Xin Jin +3 位作者 Jun Fu Xiaoyuan Yu Bei Tong Zhibo Chen 《中国科学技术大学学报》 北大核心 2025年第7期2-13,1,I0001,共14页
Collecting amounts of distorted/clean image pairs in the real world is non-trivial,which severely limits the practical application of these supervised learning-based methods to real-world image super-resolution(RealSR... Collecting amounts of distorted/clean image pairs in the real world is non-trivial,which severely limits the practical application of these supervised learning-based methods to real-world image super-resolution(RealSR).Previous works usually address this problem by leveraging unsupervised learning-based technologies to alleviate the dependency on paired training samples.However,these methods typically suffer from unsatisfactory texture synthesis due to the lack of supervision of clean images.To overcome this problem,we are the first to take a close look at the under-explored direction for RealSR,i.e.,few-shot real-world image super-resolution,which aims to tackle the challenging RealSR problem with few-shot distorted/clean image pairs.Under this brand-new scenario,we propose distortion relation guided transfer learning(DRTL)for the few-shot RealSR by transferring the rich restoration knowledge from auxiliary distortions(i.e.,synthetic distortions)to the target RealSR under the guidance of the distortion relation.Concretely,DRTL builds a knowledge graph to capture the distortion relation between auxiliary distortions and target distortion(i.e.,real distortions in RealSR).Based on the distortion relation,DRTL adopts a gradient reweighting strategy to guide the knowledge transfer process between auxiliary distortions and target distortions.In this way,DRTL is able to quickly learn the most relevant knowledge from the synthetic distortions for the target distortion.We instantiate DRTL with two commonly-used transfer learning paradigms,including pretraining and meta-learning pipelines,to realize a distortion relation-aware few-shot RealSR.Extensive experiments on multiple benchmarks and thorough ablation studies demonstrate the effectiveness of our DRTL. 展开更多
关键词 few-shot RealSR distortion relation graph transfer learning
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Identification of Cardiac Risk Factors from ECG Signals Using Residual Neural Networks
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作者 Divya Arivalagan Vignesh Ochathevan Rubankumar Dhanasekaran 《Congenital Heart Disease》 2025年第4期477-501,共25页
Background:The accurate identification of cardiac abnormalities is essential for proper diagnosis and effective treatment of cardiovascular diseases.Method:This work introduces an advanced methodology for detecting ca... Background:The accurate identification of cardiac abnormalities is essential for proper diagnosis and effective treatment of cardiovascular diseases.Method:This work introduces an advanced methodology for detecting cardiac abnormalities and estimating electrocardiographic age(ECG Age)using sophisticated signal processing and deep learning techniques.This study looks at six main heart conditions found in 12-lead electrocardiogram(ECG)data.It addresses important issues like class imbalances,missing lead scenarios,and model generalizations.A modified residual neural network(ResNet)architecture was developed to enhance the detection of cardiac abnormalities.Results:The proposed ResNet demonst rated superior performance when compared with two linear models and an alternative ResNet architectures,achieving an overall classification accuracy of 91.25%and an F1 score of 93.9%,surpassing baseline models.A comprehensive lead loss analysis was conducted,evaluating model performance across 4096 combinations of missing leads.The results revealed that pulse rate-based factors remained robust with up to 75%lead loss,while block-based factors experienced significant performance declines beyond the loss of four leads.Conclusion:This analysis highlighted the importance of addressing lead loss impacts to maintain a robust model.To optimize performance,targeted training approaches were developed for different conditions.Based on these insights,a grouping strategy was implemented to train specialized models for pulse rate-based and block-based conditions.This approach resulted in notable improvements,achieving an overall classification accuracy of 95.12%and an F1 score of 95.79%. 展开更多
关键词 ELECTROCARDIOGRAM 12-lead ECG cardiac abnormality detection ResNet machine learning deep learning electrocardiographic age lead loss analysis pulse rate-based factors block-based factors
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Applicable Regions of Spherical and Plane Wave Models for Extremely Large-Scale Array Communications
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作者 Li Renwang Sun Shu Tao Meixia 《China Communications》 2025年第5期128-151,共24页
Extremely large-scale array(XL-array)communications can significantly improve the transmission rate,spectral efficiency,and spatial resolution,and has great potential in next-generation mobile communication networks.A... Extremely large-scale array(XL-array)communications can significantly improve the transmission rate,spectral efficiency,and spatial resolution,and has great potential in next-generation mobile communication networks.A crucial problem in XLarray communications is to determine the boundary of applicable regions of the plane wave model(PWM)and spherical wave model(SWM).In this paper,we propose new PWM/SWM demarcations for XL-arrays from the viewpoint of channel gain and rank.Four sets of results are derived for four different array setups.First,an equi-power line is derived for a point-touniform linear array(ULA)scenario,where an inflection point is found at±π6 central incident angles.Second,an equi-power surface is derived for a point-touniform planar array(UPA)scenario,and it is proved that cos2(ϕ)cos2(φ)=12 is a dividing curve,where ϕ andφdenote the elevation and azimuth angles,respectively.Third,an accurate and explicit expression of the equi-rank surface is obtained for a ULA-to-ULA scenario.Finally,an approximated expression of the equirank surface is obtained for a ULA-to-UPA scenario.With the obtained closed-form expressions,the equirank surface for any antenna structure and any angle can be well estimated.Furthermore,the effect of scatterers is also investigated,from which some insights are drawn. 展开更多
关键词 effective rank extremely large-scale array(XL-array) near-/far-field Rayleigh distance spherical/plane wave
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