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Analysis and solution of streak effect in high dynamic range CMOS image sensors

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Science China(Information Sciences) 2025年第1期68卷 402-403页

作者： Wanbin ZHA Jiangtao XU Jinghua AO Kaiming NIE Zhiyuan GAO School of Microelectronics Tianjin University Tianjin key laboratory of Imaging and sensing Microelectronic technology Tianjin University

The high dynamic range (HDR) CMOS image sensor has been widely used in many fields,such as autonomous driving and security guarding [1].The dual conversion gain (DCG)structure,which adjusts the conversion gain (CG) by changing the capacitors connected to the floating diffusion (FD)nodes in the pixel,is an effective and prevalent method for realizing HDR imaging [2].While the DCG structure can extend the dynamic range,in the practical HDR imaging process,the substantial number of photo-generated electrons in bright areas can cause significant voltage variations in the pixel *** variations affect the gray values in darker areas of the same image,leading to the streak effect [3].This study primarily investigates the streak effect caused by forward conduction current of the PN junction in DCG pixels,and proposes a circuit to suppress this effect.

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Mutual-structure weighted guided image filtering for depth map restoration

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Optoelectronics Letters 2025年第1期21卷 51-56页

作者： LIU Zijian SONG Jian CHEN Quanmin XU Jiangtao Tianjin key laboratory of Imaging and sensing Microelectronic technology School of Microelectronics Tianjin University Spikesee technology Co. Ltd.

Although guided image filtering(GIF) is known for preserving edges and fast computation, it may produce inaccurate outputs in depth map restoration. In this paper, a novel confidence-weighted GIF called mutual-structure weighted GIF(MSWGIF) is proposed, which replaces the mean filtering strategy in GIF during handling overlapping windows. The confidence value is composed of a depth term and a mutual-structure term, where the depth term is utilized to protect the edges of the output, and the mutual-structure term helps to select accurate windows during the structure characteristics of the guidance image are transferred to the output. Experimental results show that MSWGIF reduces the root mean square error(RMSE) by an average of 12.37%, and the average growth rate of correlation(CORR) is 0.07% on average. Additionally, the average growth rate of structure similarity index measure(SSIM) is 0.34%.

关键词： Wiener filtering

Prospects on mangrove knowledge services in the smart era: From plant atlas to knowledge graphs

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Science China Earth Sciences 2025年第1期68卷 111-127页

作者： Zhi-Wei HOU Wenlong JING Cheng-Zhi QIN Ji YANG Qing XIA Xiaoling YIN key laboratory of Guangdong for Utilization of Remote sensing and Geographical Information System Guangdong Open Laboratory of Geospatial Information Technology and Application Guangzhou Institute of Geography Guangdong Academy of Sciences Southern Marine Science and Engineering Guangdong laboratory (Guangzhou) State key laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences College of Resources and Environment University of Chinese Academy of Sciences School of Traffic & Transportation Engineering Changsha University of Science and Technology

Mangroves are crucial to the ecological security of the Earth and human well-being. Their management, conservation, and restoration are of great importance and necessitate the support of spatio-temporal information and multidisciplinary knowledge such as biology and ecology. Traditional knowledge services such as plant atlas provide illustrated textual knowledge of mangroves. However, this kind of service is oriented to information retrieval and is incapable of effectively mining and utilizing fragmented knowledge from multi-source heterogeneous data, facing the problem of “massive data, rare knowledge”. Knowledge graphs are capable of extracting, organizing, and fusing the knowledge contained in massive data into semantic networks that can be understood and computed by computers. They provide a solution for the realization of intelligent knowledge services. Focusing on the urgent need for mangrove knowledge acquisition, formal representation, and intelligent services, this paper proposes a research prospect on mangrove knowledge graphs and knowledge services. We first analyze the similarities and differences between various domain-specific concepts of Tupu. On this basis, we define the mangrove knowledge graph as a large-scale knowledge base that integrates multi-disciplinary knowledge and spatio-temporal information with mangrove ecosystems as the core. Then, we propose a research framework for mangrove knowledge services that can realize the transformation from multi-modal data to intelligent knowledge services, including multiple research levels such as ubiquitous data sensing and aggregation, knowledge organization and graph construction, and intelligent mangrove knowledge services. Subsequently, the methods and workflow for constructing mangrove knowledge graphs are introduced. Finally, we discuss the challenges and possible future directions of mangrove knowledge services in the smart era, including the construction of a mangrove knowledge system that integra

关键词： Mangrove Tupu Knowledge graph Multi-modal Knowledge service

On-orbit attitude planning for Earth observation imaging with star-based geometric calibration

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Science China Technological Sciences 2025年

作者： Di HUANG Zhifu WANG Jianya GONG Haoran JI Institute of Aerospace Science and technology School of Remote Sensing and Information Engineering Wuhan University State key laboratory of Information Engineering in Surveying Mapping and Remote Sensing School of Remote Sensing and Information Engineering Wuhan University National key laboratory of Air-based Information Perception and Fusion Intelligent Game and Decision laboratory

To improve the quality of remote sensing images, a novel on-orbit attitude planning method for Earth observation imaging with star-based geometric calibration is presented in this study. Unlike traditional imaging processes, the proposed method includes both pre-calibration and post-calibration stages to enhance the accuracy of satellite geometric positioning. A multiple-constraint attitude planning algorithm was developed to ensure star-based calibration, wherein the satellite camera and star sensors simultaneously capture the images of stars. This integration of cameras and multiple star sensors enables effective attitude determination. During the Earth imaging stage, a fast on-orbit attitude planning algorithm was developed to determine the satellite attitude and the optimal imaging times for ground targets. Compared with existing methods, the fast on-orbit attitude planning algorithm can significantly reduce computational time and resource consumption via initial value selection and *** demonstrate the effectiveness of the proposed attitude planning method, which was successfully applied to Wuhan 1satellite.

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Lung-targeted polyzwitterionic lipid nanoparticles for effective treatment of lung inflammation

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Science China Chemistry 2025年

作者： Wen Zhang Jiaxin Li Nan Wang Muzi Li Chen Peng Xinyue Zhang Guanghui Ouyang Yan Li Beijing key laboratory for Bioengineering and sensing technology School of Chemistry and Biological Engineering University of Science and Technology Beijing CAS key laboratory of Colloid Interface and Chemical Thermodynamics Institute of Chemistry Chinese Academy of Sciences

Lipid nanoparticles (LNPs) are non-viral nucleic acid delivery systems that show great potential in vaccine development and disease treatment. Although LNPs are particularly advantageous for in vivo delivery, the wide application of LNPs is impeded as their systemic delivery of nucleic acid drugs to extrahepatic tissues remains highly challenging. To address this issue, we developed lung-targeted polyzwitterionic LNPs with zwitterionic polymer poly(2-methyacryloyloxyethyl phosphorylcholine)(PMPC) modified 1,2-dimyristoyl-sn-glycerol lipid for the delivery of small interfering RNA (siRNA). Three libraries with 90PMPC-LNPs@siRNA were established. The polyzwitterionic PMPC-LNPs had high siRNA encapsulation efficiency of about90%. The findings revealed that polyzwitterionic PMPC-LNPs@siRNA absorbed protein corona with the main component of Vitronectin, mediating lung-targeted delivery of siRNA. With good cellular uptake and endo/lysosomal escape ability, in vitro and in vivo studies demonstrated that polyzwitterionic PMPC-LNPs with siRNA against tumor necrosis factor-α (TNF-α) could significantly down-regulate the TNF-α in mRNA and protein levels, and improved the pathological features of lung inflammation. Polyzwitterionic PMPC-LNPs@siRNA achieved safe and efficient treatment of lung inflammation. Therefore, this work offered a promising siRNA therapeutic approach for lung diseases.

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Sequence-activated chemiluminescence probes: programmable illumination for high-contrast in vivo sensing and imaging

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Science China Chemistry 2025年第1期68卷 26-34页

作者： Yutao Zhang Juan Li Wei-Hong Zhu Zhiqian Guo Shanghai key laboratory of Functional Materials Chemistry Joint International Research Laboratory of Precision Chemistry and Molecular Engineering Institute of Fine Chemicals School of Chemistry and Molecular Engineering East China University of Science and Technology State key laboratory of Bioreactor Engineering Shanghai Frontier Science Research Base of Optogenetic Techniques for Cell MetabolismEast China University of Science & Technology

Sequence-activated chemiluminescence(CL) technique offers a unique approach to detecting specific biomolecules or cellular events with high sensitivity and spatial resolution. The fundamental principle behind sequence-activated CL probes involves tailoring highly-controllable CL signals in response to specific sequences or events of interest, thus enabling high-contrast signals under complex physiological conditions. This sequential activation could be triggered by enzymes, reactive oxygen species(ROS), biothiols or changes in the microenvironment. These unique sequence-activated CL probes bestow several advantages, including minimal background, deep-tissue penetration, and the ability of non-invasive or minimally invasive detection. The sequence-activated CL techniques represent a significant advancement in molecular imaging and diagnostics. In this mini-review, we focus on the latest developments in sequential CL probes, addressing the technical challenges and discussing the future trajectory by harnessing CL signaling and molecular recognition.

关键词： chemiluminescnece sequence-activation in-vivo bioimaging cyclic peroxide

Microspheres trigged-stress concentration regulating piezoelectric properties of PVDF/elastomer composites

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Science China Chemistry 2025年

作者： Wenxian Zhang Jiahong Yang Qijun Sun Lu Peng Tong Lin Shouke Yan Xiaoli Sun State key laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of Sciences State key laboratory of Separation Membranes and Membrane Processes School of Textile Science and EngineeringTiangong University key laboratory of Rubber-Plastics of Ministry of Education Shandong Provincial Key Laboratory of Rubber-PlasticsQingdao University of Science & Technology

Wearable self-powered piezoelectric pressure sensors are attracting tremendous ***,fabricating a high-sensitive elastic piezoelectric sensor for a broad response range remains ***,we assemble polar poly（vinylidene fluoride）(PVDF) microsphere-elastomer composites,achieving high-sensitive and wide-responsive pressure *** polar PVDF microspheres are produced cost-effectively through phase separation,enabling *** piezoelectric composite （PC） film demonstrates low Young’s modulus,and excellent anti-fatigue ***,the PC-based piezoelectric sensor exhibits a rather high sensitivity of 540 mV N-1in a wide sensing range （5–40 N）,240 times greater than the PVDF film-based sensor and comparable to the inorganic piezoelectric *** excellent performance is attributed to the highest average stress concentration on the spherical PVDF coupled with the remarkable deformation of dipoles of spherical PVDF in the flexible *** on excellent performance,this piezoelectric sensor achieves precise recognition of motions and sound *** high-sensitive flexible piezoelectric sensor enabling large area production with ultralow price exerts great potential in smart monitoring and intelligent robots.

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Advances in Graphene‑Based Electrode for Triboelectric Nanogenerator

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Nano-Micro Letters 2025年第1期17卷 378-403页

作者： Bin Xie Yuanhui Guo Yun Chen Hao Zhang Jiawei Xiao Maoxiang Hou Huilong Liu Li Ma Xin Chen Chingping Wong State key laboratory of Precision Electronic Manufacturing technology and Equipment Guangdong University of TechnologyGuangzhou 510006People’s Republic of China School of Electromechanical Engineering Guangdong University of TechnologyGuangzhou 510006People’s Republic of China School of Materials Science and Engineering Georgia Institute of TechnologyAtlantaGA 30332USA

With the continuous development of wearable electronics,wireless sensor networks and other micro-electronic devices,there is an increasingly urgent need for miniature,flexible and efficient nanopower generation *** nanogenerator(TENG)technology can convert small mechanical energy into electricity,which is expected to address this *** the core component of TENG,the choice of electrode materials significantly affects its *** metal electrode materials often suffer from problems such as durability,which limits the further application of ***,as a novel electrode material,shows excellent prospects for application in TENG owing to its unique structure and excellent electrical *** review systematically summarizes the recent research progress and application prospects of TENGs based on graphene *** precision processing methods of graphene electrodes are introduced,and the applications of graphene electrode-based TENGs in various scenarios as well as the enhancement of graphene electrodes for TENG performance are *** addition,the future development of graphene electrode-based TENGs is also prospectively discussed,aiming to promote the continuous advancement of graphene electrode-based TENGs.

关键词： Triboelectric nanogenerator Precision processing Graphene electrode Self-powered sensor

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Design of a terahertz slotted waveguide array antenna based on photonic crystal

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Optoelectronics Letters 2025年

作者： PAN Wu YE Kuan ZHANG Zhen LI Renpu QIU Sen HUANG Lei College of Photoelectronic Engineering， Chongqing University of Posts and Telecommunications Chongqing Municipal key laboratory of Photoelectric Information sensing and Transmission technology， Chongqing University of Posts and Telecommunications laboratory of Quantum Information technology， Chongqing University of Posts and Telecommunications

In this paper， a terahertz slotted waveguide array antenna is designed based on photonic crystal， which can realize efficient radiation of terahertz waves. The electromagnetic wave is fed from the rectangular waveguide at the bottom of the antenna， coupled to photonic crystal waveguide through photonic crystal cavity， and radiated outward through slots at the top layer of antenna. The simulation results show that the antenna achieves a peak gain of 13.45dBi at 360 GHz， a half-power beamwidth of 10.9o， and a side lobe level of -13.9dB. The antenna based on photonic crystal has the advantages of low profile， low loss， and high radiation efficiency， which can be applied to terahertz wireless communication systems.

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