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Science China(Information Sciences) 2021年第2期64卷 192-201页

作者： Pengying CHANG gang DU Xiaoyan LIU Institute of Microelectronics Peking University

Polarization evolution with space and time in HfO2based metal-ferroelectric-insulator-metal（MFIM） structure is studied based on the phase field model by self-consistently solving the two-dimensional time-dependent Ginzburg-Landau and Poisson equations. Through examining the domain wall and electrostatic（depolarization） energies compared with the negative ferroelectric（FE） anisotropy energy, the correlation between the domain pattern（phase transition） and negative capacitance（NC） effect is revealed for different structure parameters and material properties, including FE thickness and gradient coefficient,dielectric permittivity and thickness, and operation frequency of applied voltage. The design space for stabilized NC with（near） hysteresis-free operation accompanied with voltage amplification is limited by phase transition, implying the potentials and limitations of FE HfO2for energy-efficient steep-slope devices.

关键词： ferroelectric polarization dynamics hysteresis negative capacitance depolarization field

Nanomorphology in A–D–A type small molecular acceptors-based bulk heterojunction polymer solar cells

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Journal of Energy Chemistry 2019年第8期28卷 104-123,I0001,I0005页

作者： Delong Liu Ying Zhang gang Li The Department of Electronic and Information Engineering The Hong Kong Polytechnic UniversityHong Kong 999077 China The Department of Electronic and Information Engineering The Hong Kong Polytechnic University Shenzhen Research InstituteShenzhen 518057Guangdong China

Recent developments in acceptor–donor–acceptor(A–D–A) type non-fullerene acceptors have led to substantial improvements in bulk-heterojunction polymer solar cells efficiency. The device performance strongly depends on photoactive layer morphology, as the molecular packing, donor–acceptor interface and phase separation significantly affect the charge-transfer states and charge carrier dynamics. In this review, we start with a brief introduction of the techniques most effectively utilized to characterize multiphase morphology. Then, we summarize recent progress in A–D–A type acceptors, with the emphasis on understanding the molecular structure–morphology–performance relationships. Finally, an outlook on correlating morphological characteristics with photovoltage losses is presented for further improving device performance.

关键词： Polymer solar cells Bulk heterojunction Nanomorphology Non-fullerene acceptor A–D–A type small molecules

A 3-color Theorem on Plane Graphs without 5-circuits

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Acta Mathematica Sinica,English Series 2007年第6期23卷 1059-1062页

作者： Bao gang XU School of Math. & Computer Science Nanjing Normal University Nanjing 210097 P. R. China

In this paper, we prove that every plane graph without 5-circuits and without triangles of distance less than 3 is 3-colorable. This improves the main result of Borodin and Raspaud [Borodin, O. V., Raspaud, A.： A sufficient condition for planar graphs to be 3-colorable. Journal of Combinatorial Theory, Ser. B, 88, 17-27 （2003）], and provides a new upper bound to their conjecture.

关键词： plane graph circuit coloring

State-sensitive convolutional sparse coding for potential biomarker identification in brain signals

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Science China(Information Sciences) 2024年第5期67卷 270-286页

作者： Puli WANG Yu QI gang PAN College of Computer Science and Technology Zhejiang University State Key Laboratory of Brain-Machine Intelligence Zhejiang University MOE Frontier Science Center for Brain Science and Brain-machine Integration Zhejiang University Affiliated Mental Health Center & Hangzhou Seventh People's Hospital Zhejiang University School of Medicine

The identification of prototypical waveforms, such as sleep spindles and epileptic spikes, is crucial for the diagnosis of neurological disorders. These prototypical waveforms are usually recurrently presented in certain brain states, serving as potential biomarkers for clinical evaluations. Convolutional sparse coding(CSC) approaches have demonstrated strength in identifying recurrent patterns in time-series. However,existing CSC approaches do not explicitly explore state-specific patterns, making it difficult to identify state-related biomarkers. To address this problem, we propose state-sensitive CSC to learn state-specific prototypical waveforms. Specifically, we model signals of a certain state with specific waveforms that only appear frequently in this state and background waveforms that are independent of states. Based on this,state-sensitive CSC separates state-specific waveforms from background ones explicitly by incorporating incoherence constraints into optimizations. Experiments with epilepsy brain signals demonstrate that our approach can effectively identify prototypical waveforms in pre-ictal states, providing potential biomarkers for seizure prediction. Our approach provides a promising tool for automatic biomarker candidate identification.

关键词： convolutional sparse coding prototypical waveforms state-specific dictionary biomarker identification neural signal processing

The Association between Lower Incisal Inclination and Morphology of the Supporting Alveolar Bone—A Cone-Beam CT Study

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International Journal of Oral Science 2009年第4期1卷 217-223页

作者： Quan Yu Xiao-gang Pan Guo-ping Ji gang Shen Shanghai Key Laboratory of Stomatology Department of Orthodontics Shanghai Ninth People＇s Hospital Affiliated toShanghai Jiao Tong University School of Medicine Shanghai China

Aim To investigate the relationship between the positioning of the lower central incisor and physical morphology of the surrounding alveolar bone. Methodology Thirty-eight patients （18 males, 20 females）, with mean age of 13.4 years, were included in this study. As part of orthodontic treatment planning the patients were required to take dental Cone-beam CT （CBCT） covering the region of lower incisors, the sur- rounding alveolar bone and the mandibular symphysis. The cephalometric parameters were designed and measured to indicate the inclination of lower central incisor and physical morphology of the adjacent alveolar bone. Computer-aided descriptive statistical analysis was performed using SPSS 15.0 software package for Windows. A correlation analysis and a linear regression analysis between the incisor inclination and the alveolar bone morphology were performed. Results Significant positive correlations were found between the lower central incisor inclination and the morphological contour of the alveolar bone （P〈0.05）. The lower central incisor root apex was closer to the lingual alveolar crest when it was buccally inclined. Conclusion The morphology of the alveolar bone may be affected by incisal inclination.

关键词： Cone-beam CT (CBCT) alveolar bone incisorinclination

Heavy metal accumulation characteristics and physiological response of Sabina chinensis and Platycladus orientalis to atmospheric pollution

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Journal of Environmental Sciences 2022年第2期34卷 192-201页

作者： Ning Cui Laiye Qu gang Wu State Key Laboratory of Urban and Regional Ecology Research Center for Eco-environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

Heavy metal(Cu,Mn,Zn,Pb,and Cd)concentrations were measured in the leaves of Sabina chinensis and Platycladus orientalis collected from urban,suburban,and rural sites in Tianjin,*** pigment contents,reactive oxygen species content,malondialdehyde(MDA)content and antioxidant enzyme activity were investigated,providing physiological response *** comparison of the sites revealed that urbanization significantly influenced the heavy metal concentrations in both plant *** the rural site,both plant leaves exhibited the lowest heavy metal *** highest Cu,Mn,and Zn concentrations were found in *** leaves from the urban site;the highest Pb and Cd concentrations were found in *** leaves from the urban *** results indicate that the urban site contained larger heavy metal concentrations in the plant leaves that may reflect the anthropogenic emission *** is also found that *** may be used to monitor airborne heavy metal pollution because it is highly quick response to heavy metals,while *** may be used for mitigation due to its high *** results of this study can contribute to the development of monitoring and environmental management plans by providing information on sensitive and resistant tree species for city greening in North China.

关键词： Atmospheric heavy metal pollutions Sabina chinensis Platycladus orientalis Physiological responses

Lyapunov-Based Output Containment Control of Heterogeneous Multi-Agent Systems With Markovian Switching Topologies and Distributed Delays

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IEEE/CAA Journal of Automatica Sinica 2023年第6期10卷 1421-1433页

作者： Haihua Guo Min Meng gang Feng the Department of Biomedical Engineering City University of Hong KongHong KongChina the Department of Control Science and Engineering College of Electronics and Information Engineeringand Shanghai Research Institute of Intelligent Autonomous SystemsTongji UniversityShanghai 200092China

This paper considers the mean square output containment control problem for heterogeneous multi-agent systems(MASs)with randomly switching topologies and nonuniform distributed *** modeling the switching topologies as a continuous-time Markov process and taking the distributed delays into consideration,a novel distributed containment observer is proposed to estimate the convex hull spanned by the leaders'states.A novel distributed output feedback containment controller is then designed without using the prior knowledge of distributed *** constructing a novel switching Lyapunov functional,the output containment control problem is then solved in the sense of mean square under an easily-verifiable sufficient ***,two numerical examples are given to show the effectiveness of the proposed controller.

关键词： Heterogeneous multi-agent systems Lyapunov method Markovian switching topologies output containment control time delays

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台州市城市绿色货运发展路径探讨

交通企业管理 2025年第1期40卷 92-94页

作者：周昀中陈刚台州市公路与运输管理中心浙江省交通运输科学研究院

城市绿色货运发展是国家“2030年前碳达峰,2060年前碳中和”战略目标提出后的必然要求。加快推进城市绿色货运发展,既有助于加速城市货运物流节能减排,降低环境污染,又能进一步促进物流资源整合,推动物流业降本增效。一、城市绿色货运... 详细信息

城市绿色货运发展是国家“2030年前碳达峰,2060年前碳中和”战略目标提出后的必然要求。加快推进城市绿色货运发展,既有助于加速城市货运物流节能减排,降低环境污染,又能进一步促进物流资源整合,推动物流业降本增效。一、城市绿色货运的定义与特征1.城市绿色货运的定义城市绿色货运,作为绿色物流的重要环节.

关键词：城市配送绿色货运节能减排公共配送货运配送冷链配送

Metal-based nanoparticles for cardiovascular disease diagnosis and therapy

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Particuology 2023年第1期72卷 94-111页

作者： Lei Li Yun Zeng gang Liu State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics Center for Molecular Imaging and Translational MedicineSchool of Public HealthXiamen UniversityXiamen 361102China Department of Pharmacy Xiamen Medical CollegeXiamen 361023China

Cardiovascular diseases (CVDs) are the most prominent cause of disability and mortality in the world. Although there have been a variety of therapeutic options for the management of CVDs, most of the traditional therapeutic strategies could not sufficiently stop or reduce the progression of these diseases and may result in some side effects. With the advance in nanotechnology, a number of metal-based nanoparticles have been developed and shown promising potentials in the treatment of CVDs. In this review, we provide a comprehensive review of researches on recent development of metal-based nanoparticles in diagnosis and therapy in CVDs as biomedical materials. We also discuss the challenges in the clinical translation and potential risks in their application of CVD therapy. Based on the ongoing research and applications, we can conclude metal-based nanoparticles are expected to become potential therapeutics for the treatment of CVDs. But their application is still in its infancy and much more efforts should be made to enforce a clinical breakthrough.

关键词： Metal-based nanoparticles Nanomedicine Cardiovascular diseases Diagnosis Therapy

Distributed Adaptive Output Consensus of Unknown Heterogeneous Non-Minimum Phase Multi-Agent Systems

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IEEE/CAA Journal of Automatica Sinica 2023年第4期10卷 997-1008页

作者： Wenji Cao Lu Liu gang Feng Department of Biomedical Engineering City University of Hong KongHong Kong SARChina

This article addresses the leader-following output consensus problem of heterogeneous linear multi-agent systems with unknown agent parameters under directed *** dynamics of followers are allowed to be non-minimum phase with unknown arbitrary individual relative *** is contrary to many existing works on distributed adaptive control schemes where agent dynamics are required to be minimum phase and often of the same relative degree.A distributed adaptive pole placement control scheme is developed,which consists of a distributed observer and an adaptive pole placement control *** is shown that under the proposed distributed adaptive control scheme,all signals in the closed-loop system are bounded and the outputs of all the followers track the output of the leader *** effectiveness of the proposed scheme is demonstrated by one practical example and one numerical example.

关键词： Adaptive pole placement control heterogeneous multi-agent systems leader-following output consensus non-minimum phase