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Joint fuzzy background and adaptive foreground model for moving target detection

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Frontiers of Computer Science 2024年第2期18卷 93-106页

作者： Dawei ZHANG Peng WANG Yongfeng dong linhao li Xin li School of Artificial Intelligence Hebei University of TechnologyTianjin 300401China Lane Department of Computer Science and Electrical Engineering West Virginia UniversityMorgantownWV 26506-6109USA

Moving target detection is one of the most basic tasks in computer *** conventional wisdom,the problem is solved by iterative optimization under either Matrix Decomposition(MD)or Matrix Factorization(MF)*** utilizes foreground information to facilitate background *** uses noise-based weights to fine-tune the *** both noise and foreground information contribute to the recovery of the *** jointly exploit their advantages,inspired by two framework complementary characteristics,we propose to simultaneously exploit the advantages of these two optimizing approaches in a unified framework called Joint Matrix Decomposition and Factorization(JMDF).To improve background extraction,a fuzzy factorization is *** fuzzy membership of the background/foreground association is calculated during the factorization process to distinguish their contributions of both to background *** describe the spatio-temporal continuity of foreground more accurately,we propose to incorporate the first order temporal difference into the group sparsity constraint *** temporal constraint is adjusted *** foreground and the background are jointly estimated through an effective alternate optimization process,and the noise can be modeled with the specific probability *** experimental results of vast real videos illustrate the effectiveness of our *** with the current state-of-the-art technology,our method can usually form the clearer background and extract the more accurate ***-noise experiments show the noise robustness of our method.

关键词： matrixdecomposition matrix factorization generalized sparsity noise modeling

Comparison of Direct Pore-Scale and Volume-Averaging Methods for the Performance Evaluation of Porous Volumetric Solar Receiver

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Journal of Thermal Science 2024年第5期33卷 1607-1617页

作者： DU Shen HE Yaling li dong liU Zhanbin li Mengjie National Innovation Platform(Center)for Industry-Education Integration of Energy Storage Technology Key Laboratory of Thermo-Fluid Science and Engineering of Ministry of EducationXi’an Jiaotong UniversityXi’an710049China

Direct pore-scale and volume-averaging numerical simulations are two methods for investigating the performance of porous volumetric solar *** clarify the difference in the prediction of heat transfer processes,a direct comparison between these two methods was conducted at both steady state and transient *** numerical models were established based on X-ray computed tomography scans and a local thermal non-equilibrium model,*** empirical parameters,which are indispensable to the volume-averaging simulation,were determined by Monte Carlo ray tracing and direct pore-scale numerical *** predicted outlet air temperature of the receiver by the volume-averaging simulation method corresponded satisfactorily to that in the direct pore-scale *** largest discrepancies were observed when the receiver's working temperature was elevated,with differences of 5.5%and 3.68%for the steady state and transient state simulations,***,the volume-averaging method is incapable of capturing the local temperature information of the air and porous *** underestimates the inlet temperature of the receiver,leading to an overestimation of the receiver's thermal efficiency,with the largest difference being 6.51%.The comparison results show that the volume-averaging model is a good approximation to the pore-scale model when the empirical parameters are carefully selected.

关键词： porous media volumetric solar receiver pore-scale method volume-averaging method thermal performance

SG-NeRF:Sparse-Input Generalized Neural Radiance Fields for Novel View Synthesis

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Journal of Computer Science & Technology 2024年第4期39卷 785-797页

作者： Kuo Xu Jie li zhen-Qiang li Yang-Jie Cao School of Cyber Science and Engineering Zhengzhou UniversityZhengzhou 450002China Intelligent Big Data System(iBDSys)Lab Shanghai Jiao Tong UniversityShanghai 200240China School of Computer and Artificial Intelligence Zhengzhou UniversityZhengzhou 450001China

Traditional neural radiance fields for rendering novel views require intensive input images and pre-scene optimization,which limits their practical *** propose a generalization method to infer scenes from input images and perform high-quality rendering without pre-scene optimization named SG-NeRF(Sparse-Input Generalized Neural Radiance Fields).Firstly,we construct an improved multi-view stereo structure based on the convolutional attention and multi-level fusion mechanism to obtain the geometric features and appearance features of the scene from the sparse input images,and then these features are aggregated by multi-head attention as the input of the neural radiance *** strategy of utilizing neural radiance fields to decode scene features instead of mapping positions and orientations enables our method to perform cross-scene training as well as inference,thus enabling neural radiance fields to generalize for novel view synthesis on unseen *** tested the generalization ability on DTU dataset,and our PSNR(peak signal-to-noise ratio)improved by 3.14 compared with the baseline method under the same input *** addition,if the scene has dense input views available,the average PSNR can be improved by 1.04 through further refinement training in a short time,and a higher quality rendering effect can be obtained.

关键词： Neural Radiance Fields(NeRF) multi-view stereo(MVS) new view synthesis(NVS)

Photoinduced Room-Temperature Phosphorescence of Triphenylamine-Phenothiazine Derivative-Doped Polymers

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有机化学 2024年第8期44卷 2487-2494页

作者： li Nan Wang Yunsheng li zhen Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou 350207 Institute of Molecular Aggregation Science Tianjin UniversityTianjin 300072 Hubei Key Lab on Organic and Polymeric Opto-Electronic Materials Department of ChemistryWuhan UniversityWuhan 430072

Photo-responsive room-temperature phosphorescent(RTP)materials have garnered significant interest due to the advantages of rapid response,spatiotemporal control,and contactless precision ***,the development of such materials remains in its infancy,underscoring the importance of exploiting novel and efficient light-responsive RTP *** this work,three phenothiazine derivatives of TPA-PTZ,TPA-2PTZ,and TPA-3PTZ were successfully synthesized via the Buchwald-Hartwig C—N coupling *** embedding these molecules as RTP guests into polymethyl methacrylate(PMMA)matrix,photo-induced RTP properties were *** sustained UV irradiation,there was an enhancement of 19 times in the quantum yield to reach a value of 5.68%.Remarkably,these materials exhibit superior alongside robust light and thermal stability,maintaining high phosphorescence intensity even after prolonged UV exposure(irradiation for>200 s by a 365 nm UV lamp with the power of 500μW·cm-2)or at higher temperature up to 75℃.The outstanding properties of these photo-induced RTP materials make them promising candidates for applications in information encryption,anti-counterfeiting,and advanced optical materials.

关键词： stimuli-responsive luminescent materials photo-induced room-temperature phosphorescence phenothiazine derivatives doped polymer

Engineering Rubisco to enhance CO_(2) utilization

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Synthetic and Systems Biotechnology 2024年第1期9卷 55-68页

作者： Lei Zhao zhen Cai Yin li Yanping Zhang CAS Key Laboratory of Microbial Physiological and Metabolic Engineering State Key Laboratory of Microbial ResourcesInstitute of MicrobiologyChinese Academy of SciencesBeijing100101China University of Chinese Academy of Sciences Beijing100049China Seeds Research Syngenta Biotechnology ChinaZhong Guan Cun Life Science ParkBeijingChina

Ribulose-1,5-bisphosphate carboxylase/oxygenase(Rubisco)is a pivotal enzyme that mediates the fixation of CO_(2).As the most abundant protein on earth,Rubisco has a significant impact on global carbon,water,and nitrogen ***,the significantly low carboxylation activity and competing oxygenase activity of Rubisco greatly impede high carbon fixation *** review first summarizes the current efforts in directly or indirectly modifying plant Rubisco,which has been challenging due to its high conservation and limitations in chloroplast transformation ***,recent advancements in understanding Rubisco biogenesis with the assistance of chaperones have enabled successful heterologous expression of all Rubisco forms,including plant Rubisco,in *** breakthrough facilitates the acquisition and evaluation of modified proteins,streamlining the measurement of their ***,the establishment of a screening system in *** opens up possibilities for obtaining high-performance mutant enzymes through directed ***,this review emphasizes the utilization of Rubisco in microorganisms,not only expanding their carbon-fixing capabilities but also holding significant potential for enhancing biotransformation processes.

关键词： Rubisco Plant CO_(2)fixation Microbial Carbon fixation pathway Synthetic biology Enzyme engineering

Design and fabrication of Nd-Fe-B magnet with excellent thermal stability

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Journal of Rare Earths 2024年第5期42卷 980-986,I0006页

作者： Rui Han Shengzhi dong dong li dongmin Zhang Hongsheng Chen Jiyuan Xu George CHadjipanayis Zhuolin li Ying Zhang Wei li Division of Functional Materials Research Central Iron and Steel Research InstituteBeijing100081China Department of Physics and Astronomy Sharp Lab University of DelawareNewarkDE19716USA Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing100190China

A novel Nd-Fe-B type permanent magnet with excellent thermal stability was designed by Co replacing Fe in the main phase and the grain boundary *** remanence and coercivity temperature coefficient reach 0.058%/℃and 0.465%/℃in the te mperature range from 25 to 100℃,which are much lower than those of commercial Nd-Fe-B *** enhanced Curie temperature is obtained for the novel magnet due to the Co substitution,which significantly improves the operating *** microstructure result reveals that an amorphous phase exists in the intergranular grains which is probably responsible for the deterioration of intrinsic *** work can provide a reference for the design and optimization of components of sintered Nd-Fe-B magnets with excellent thermal stability.

关键词： Thermal stability Remanence temperature coefficient Operating temperature Atomic substitution Rare earths

Adjuvant Therapy for Hepatocellular Carcinoma After Curative Treatment:Several Unanswered Questions

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Journal of Clinical and Translational Hepatology 2024年第5期12卷 525-533页

作者： Le li zhen-zhen li li-Xin Pan Jia-Yong Su Shan Huang liang Ma Jian-Hong Zhong Hepatobiliary Surgery Department Guangxi Medical University Cancer HospitalNanningGuangxiChina Guangxi Academy of Medical Sciences Emergency DepartmentThe People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxiChina Pathology Department Guangxi Medical University Cancer HospitalNanningGuangxiChina Key Laboratory of Early Prevention and Treatment for Regional High Frequency Tumor(Guangxi Medical University) Ministry of EducationNanningGuangxiChina Guangxi Key Laboratory of Early Prevention and Treatment for Regional High Frequency Tumor NanningGuangxiChina

Most patients with hepatocellular carcinoma(HCC)have a poor *** and local ablation are the main curative treatments for ***,the recurrence rate after hepatectomy or ablation is up to 70%,which seriously affects patient *** adjuvant therapies have been explored to reduce postoperative ***,although a variety of adjuvant therapies have been shown to reduce the recurrence rate and improve overall survival,a standard consensus of national HCC guidelines for adjuvant treatment is ***,there are significant differences in the recommendations for adjuvant therapy for HCC between the Eastern and Western guidelines.A variety of adjuvant treatment methods,such as antiviral therapy,transarterial chemoembolization or traditional Chinese medicine,are recommended by the Chinese HCC ***,Western guidelines make few recommendations other than antiviral *** immune checkpoint inhibitors are recommended only in the recently updated American Association for the Study of liver Diseases *** review summarized the existing adjuvant therapy options after curative hepatectomy or ablation and discusses several important dilemmas of adjuvant treatments.

关键词： Hepatocellular carcinoma Adjuvant therapy Curative hepatectomy Recurrence Overall survival Immune checkpoint inhibitor

Numerical investigation on the flow and thermal behaviors of the volumetric solar receivers with different morphologies

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Science China(Technological Sciences) 2024年第9期67卷 2749-2757页

作者： DU Shen li dong li MengJie HE Yaling National Innovation Platform(Center)for Industry-Education Integration of Energy Storage Technology Key Laboratory of Thermo-Fluid Science and Engineering of Ministry of EducationXi’an Jiaotong UniversityXi’an 710049China

Morphologies of the porous materials influence the processes of solar radiation transport, flow, and thermal behaviors within volumetric solar receivers. A comprehensive comparative study is conducted by applying pore scale numerical simulations on volumetric solar receivers featuring various morphologies, including Kelvin, Weaire-Phelan, and foam configurations. The idealized unit cell and X-ray computed tomography scan approaches are employed to reconstruct pore scale porous *** Carlo ray tracing and pore scale numerical simulations are implemented to elucidate the radiative, flow, and thermal behaviors of distinct receivers exposed to varying thermal boundary conditions and real irradiation situations. The findings demonstrate that the foam structure exhibits greater solar radiation absorptivity, while Kelvin and Weaire-Phelan structures enhance the penetration depth under non-perpendicular solar irradiation. In comparison with Kelvin and Weaire-Phelan configurations, the foam structure presents efficient convective heat transfer, with the Weaire-Phelan structure showing pronounced thermal non-equilibrium phenomena. The variance in convective heat transfer coefficient between Kelvin and Weaire-Phelan configurations is approximately 8.4%. The foam structure exhibits higher thermal efficiency and flow resistance under nonperpendicular irradiation compared to Kelvin and Weaire-Phelan structures, attributed to its smaller pore size and intricate flow channels. An increase of 1.3% in thermal efficiency is observed with a substantial rise in pressure drop of 32.2%.

关键词： volumetric solar receiver porous morphology pore scale method solar radiation absorption thermal performance flow resistance

Compositionally graded high-voltage P2-type cathode with superior structural stability and redox kinetics for advanced Na-ion batteries

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Nano Research 2024年第4期17卷 2755-2762页

作者： Peiyu Hou Mohan dong zhenbo Sun Feng li School of Physics and Technology University of JinanJinan 250022China

Layered P2-type cathodes with high voltage,large capacity,and easy synthesis show great potential for developing sodium(Na)-ion batteries(NIBs).However,the P2–O2 phase transition makes their structural degradation and the Na^(+)/vacancy ordering lowers their redox ***,we rationally propose a compositionally graded P2-type cathode,where nickel(Ni)and manganese(Mn)fractions decrease gradually,and cobalt(Co)content increases contiguously from the inside to the outside of a secondary *** these particles,the Ni/Mn-based compound delivers high capacity and high *** the surface of particles,the Co/Mn-based solid solution offers a stable buffer *** from these synergistic effects,this graded P2-type cathode shows the elimination of P2–O2 transformation even when charged to 4.4 V,which enables good structural stability,maintaining capacity retention reaching~80%within 300 ***,the Na^(+)/vacancy ordering superstructure is further suppressed,and the Na^(+)diffusion kinetics is significantly *** proposed graded structure with optimized chemical composition offers a new perspective for eliminating the unwanted phase transition and thus enhancing the electrochemistry of high-voltage layered cathodes for advanced NIBs.

关键词： Na-ion battery P2-type cathode composition regulation phase transition redox stability