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Macroscopic model and statistical model to characterize electromagnetic information of a digital coding metasurface

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National Science Review 2024年第3期11卷 159-171页

作者： Rui Wen shao Jun Wei Wu Zheng Xing Wang hui Xu Han Qing Yang Qiang Cheng Tie Jun cui Institute of Electromagnetic Space Southeast University State Key Laboratory of Millimeter Waves Southeast University Peng Cheng Laboratory Pazhou Laboratory(Huangpu)

A digital coding metasurface is a platform connecting the digital space and electromagnetic wave space, and has therefore gained much attention due to its intriguing value in reshaping wireless channels and realizing new communication architectures. Correspondingly, there is an urgent need for electromagnetic information theory that reveals the upper limit of communication capacity and supports the accurate design of metasurface-based communication systems. To this end, we propose a macroscopic model and a statistical model of the digital coding metasurface. The macroscopic model uniformly accommodates both digital and electromagnetic aspects of the meta-atoms and predicts all possible scattered fields of the digital coding metasurface based on a small number of simulations or measurements. Full-wave simulations and experimental results show that the macroscopic model is feasible and accurate. A statistical model is further proposed to correlate the mutual coupling between meta-atoms with covariance and to calculate the entropy of the equivalent currents of digital coding metasurface. These two models can help reconfigurable intelligent surfaces achieve more accurate beamforming and channel estimation, and thus improve signal power and coverage. Moreover, the models will encourage the creation of a precoding codebook in metasurface-based direct digital modulation systems, with the aim of approaching the upper limit of channel capacity. With these two models, the concepts of current space and current entropy, as well as the analysis of information loss from the coding space to wave space, is established for the first time, helping to bridge the gap between the digital world and the physical world, and advancing developments of electromagnetic information theory and new-architecture wireless systems.

关键词： electromagnetic information theory current entropy current space digital coding metasurface macroscopic model statistical model

Paleogene transgression process and environmental evolution in the deepwater area of the Baiyun Depression in the northern South China Sea

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Acta Oceanologica Sinica 2024年第4期43卷 15-24页

作者： Peijun Qiao Yuchi cui Qiong Ma Qiang Yu Lei shao State Key Laboratory of Marine Geology Tongji UniversityShanghai 200092China CNOOC Energy Technology&Services-Drilling&Production Co. CNOOC Central Laboratory Shenzhen BranchGuangdong 516000China

Multiple borehole samples are collected from the Baiyun Depression in deep-water area of the northern South China Sea(SCS)in an effort to reconstruct transgression processes during the Paleogene based on palynalgal *** study indicates that the Baiyun Depression generated a large group of palynopore assemblages and fluvial/lacustrine-related algae during the early and middle Eocene when the Wenchang Formation was *** entire depression was dominated by fluvial and lacustrine facies before *** eastern and southeastern sags transitioned to shallow marine environment by generating a large abundance of marine dinoflagellates during the Enping deposition of the late ***,the southern uplift zone simply yielded fluvial/lacustrine-related palynopores and algae,and was dominated by the fluvial and lacustrine environment during the early stage of the Enping Formation,prior to shifting into transitional setting in the later *** sags remained extensive fluvial and delta facies without existence of marine *** was until the depositional stage of the Zhuhai Formation(Oligocene)that the overall depression was strongly impacted from transgression *** eastern and southeastern sags were mainly under deep marine setting on a continental slope while northwestern and southern areas developed transitional *** distribution and accumulation patterns varied greatly among sub-sags,the overall Baiyun Depression was characterized by widespread development of marine *** should be noted that the northwestern sag also partly generated large-scale river delta *** to the eustatic rise and change of SCS spreading axis,the overall Baiyun Depression was mostly influenced by the deep marine environment on a continental slope during the early *** northwestern sag and southern uplift zone were found plentiful marine *** summary,transgression initiated from the ea

关键词： South China Sea Paleogene transgression sedimentary environment plant ecology

Modeling of Rectangular Microchannel Heat Sink with Non-Uniform Channels and Multi-Objective Optimization

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Journal of Thermal Science 2024年第5期33卷 1701-1711页

作者： SHANG Xueshuo WANG Yixin LI Qingwen WANG Rui cui Zheng shao Wei Institute of Advanced Technology Shandong UniversityJi'nan 250014China Institute of Thermal Science and Technology Shandong UniversityJi'nan 250014China Shandong Institute of Advanced Technology Ji'nan 250100China

Rectangular microchannel heat sinks(MCHS)are widely used to cool high-heat-flux electronic ***,previous studies focused mainly on MCHS with uniform channels(UCs).This study considers a microchannel heat sink with non-uniform channels(NUCs).A mathematical model is developed based on energy equations and the Darcy flow *** expressions for total thermal resistance and coolant pressure drop are derived using the thermoelectric *** and numerical simulations are performed to verify the mathematical *** non-uniformity increases,total coolant pressure drop decreases but at the cost of higher thermal *** overall performance of NUCs is better than that of UCs because of their lower ratio of pumping power to cooling *** transfer performance of NUCs changes little for more than 120 channels and depends mainly on channel arrangement.A multi-objective optimization is conducted to minimize the thermal resistance and pumping power of an *** optimal NUC saves 64%pumping power compared with a conventional UC for the total thermal resistance of 0.1℃/W,indicating that the use of non-uniform channels could be very helpful to reduce the flow resistance of MCHS.

关键词： microchannel heat sink non-uniform channel mathematical model multi-objective optimization

Knowledge Distillation via Hierarchical Matching for Small Object Detection

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Journal of Computer Science & Technology 2024年第4期39卷 798-810页

作者： Yong-Chi Ma Xiao Ma Tian-Ran Hao Li-Sha cui shao-hui Jin Pei Lyu School of Computer Science and Artificial Intelligence Zhengzhou UniversityZhengzhou 450000China

Knowledge distillation is often used for model compression and has achieved a great breakthrough in image classification,but there still remains scope for improvement in object detection,especially for knowledge extraction of small *** main problem is the features of small objects are often polluted by background noise and not prominent due to down-sampling of convolutional neural network(CNN),resulting in the insufficient refinement of small object features during *** this paper,we propose Hierarchical Matching Knowledge Distillation Network(HMKD)that operates on the pyramid level P2 to pyramid level P4 of the feature pyramid network(FPN),aiming to intervene on small object features before *** employ an encoder-decoder network to encapsulate low-resolution,highly semantic information,akin to eliciting insights from profound strata within a teacher network,and then match the encapsulated information with high-resolution feature values of small objects from shallow layers as the *** this period,we use an attention mechanism to measure the relevance of the inquiry to the feature *** in the process of decoding,knowledge is distilled to the *** addition,we introduce a supplementary distillation module to mitigate the effects of background *** show that our method achieves excellent improvements for both one-stage and twostage object ***,applying the proposed method on Faster R-CNN achieves 41.7%mAP on COCO2017(ResNet50 as the backbone),which is 3.8%higher than that of the baseline.

关键词： knowledge distillation object detection small object detection machine learning

Real-time Abnormal Detection of GWAC Light Curve based on Wavelet Transform Combined with GRU-Attention

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Research in Astronomy and Astrophysics 2024年第5期24卷 151-168页

作者： Hao Li Qing Zhao Long shao Tao Liu Chenzhou cui Yunfei Xu College of Artifcial Intelligence Tianjin University of Science and TechnologyTianjin 300457China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China

Nowadays, astronomy has entered the era of Time-Domain Astronomy, and the study of the time-varying light curves of various types of objects is of great significance in revealing the physical properties and evolutionary history of celestial bodies. The Ground-based Wide Angle Cameras telescope, on which this paper is based, has observed more than 10 million light curves, and the detection of anomalies in the light curves can be used to rapidly detect transient rare phenomena such as microgravity lensing events from the massive data. However, the traditional statistically based anomaly detection methods cannot realize the fast processing of massive data. In this paper, we propose a Discrete Wavelet(DW)-Gate Recurrent Unit-Attention(GRU-Attention) light curve warning model. Wavelet transform has good effect on data noise reduction processing and feature extraction, which can provide richer and more stable input features for a neural network, and the neural network can provide more flexible and powerful output model for wavelet transform. Comparison experiments show an average improvement of 61% compared to the previous pure long-short-term memory unit(LSTM) model, and an average improvement of 53.5% compared to the previous GRU model. The efficiency and accuracy of anomaly detection in previous paper work are not good enough, the method proposed in this paper possesses higher efficiency and accuracy,which incorporates the Attention mechanism to find out the key parts of the light curve that determine the anomalies. These parts are assigned higher weights, and in the actual anomaly detection, the star is detected with83.35% anomalies on average, and the DW-GRU-Attention model is compared with the DW-LSTM model, and the detection result f1 is improved by 5.75% on average, while having less training time, thus providing valuable information and guidance for astronomical observation and research.

关键词： methods data analysis-stars variables general-techniques photometric

MnO_(2)-coated nanodiamond-driven photodynamic therapy for enhanced antitumor effect by addressing hypoxia and glutathione depletion

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Particuology 2024年第9期92卷 305-315页

作者： Jicheng cui Dongmei Zhang hui Qiao Zeyu Yan Wenxia Zhang Yingqi Li Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education Institute of Molecular ScienceShanxi UniversityTaiyuan030006China Taiyuan Central Hospital Taiyuan030009China School of Chemistry and Chemical Engineering Shanxi UniversityTaiyuan030006China

The generation of reactive oxygen species(ROS)at the tumor site to induce destruction is emerging as a novel strategy for cancer treatment,which involves photodynamic therapy(PDT).Nevertheless,tumors typically create a hypoxic environment and are equipped with an endogenous antioxidant defense system that could potentially impede the efficiency of the therapeutic *** overcome these drawbacks,herein,a tumor microenvironment-responsive the ND-PAA-CD-Ce6@MnO_(2)(NPCC@M)delivery system was fabricated by disulfide bond coupling chlorin e6(Ce6)to nanodiamond(ND)and further wrapped by MnO_(2)nanosheets to facilitate *** use of disulfide bond not only stabilizes Ce6 in the blood circulation to prevent premature leakage,but also destroys the antioxidant barrier of overexpressed glutathione(GSH)in tumor ***,the outer MnO_(2)was rapidly degraded by the endogenous hydrogen peroxide(H_(2)O_(2))in the acidic pH and GSH within the tumor cells,which leads to an abundance of O_(2)and while increases the level of 1O_(2)under laser *** results eventually broke the redox homeostasis and attenuate hypoxia,thereby inducing apoptosis and necrosis of tumor *** in vitro and in vivo biological effect has revealed a good biosafety profile and a high tumor suppression *** a novel ND-based system with tumor microenvironment-modulating capability to elevate oxygen content and promote GSH consumption in tumor cells opens new opportunities for enhanced ROS treatment paradigms.

关键词： Nanodiamond Photodynamic Chlorin e6 MnO_(2) Tumor suppression

Siliceous mesocellular foam supported Cu catalysts for promoting non-thermal plasma activated CO_(2) hydrogenation toward methanol synthesis

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Frontiers of Chemical Science and Engineering 2024年第7期18卷 55-65页

作者： Yi Chen shaowei Chen Yan shao cui Quan Ningbo Gao Xiaolei Fan Huanhao Chen State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China School of Environmental Science and Engineering Nanjing Tech UniversityNanjing 211816China School of Energy and Power Engineering Xi’an Jiaotong UniversityXi’an 710049China Department of Chemical Engineering School of EngineeringThe University of ManchesterManchester M139PLUK Nottingham Ningbo China Beacons of Excellence Research and Innovation Institute University of Nottingham Ningbo ChinaNingbo 315048China Institute of Wenzhou Zhejiang UniversityWenzhou 325006China

Electrified non-thermal plasma (NTP) catalytic hydrogenation is the promising alternative to the thermal counterparts, being able to be operated under mild conditions and compatible with green electricity/hydrogen. Rational design of the catalysts for such NTP-catalytic systems is one of the keys to improve the process efficiency. Here, we present the development of siliceous mesocellular foam (MCF) supported Cu catalysts for NTP-catalytic CO_(2) hydrogenation to methanol. The findings show that the pristine MCF support with high specific surface area and large mesopore of 784 m2·g−1 and ~8.5 nm could promote the plasma discharging and the diffusion of species through its framework, outperforming other control porous materials (viz., silicalite-1, SiO_(2), and SBA-15). Compared to the NTP system employing the bare MCF, the inclusion of Cu and Zn in MCF (i.e., Cu1Zn1/MCF) promoted the methanol formation of the NTP-catalytic system with a higher space-time yield of methanol at ~275 μmol·g_(cat)^(−1)·h^(−1) and a lower energy consumption of 26.4 kJ^(−1)·mmol_(CH_(3)OH)^(-1) (conversely, ~225 μmol·g_(cat)^(−1)·h^(−1) and ~71 kJ^(−1)·mmol_(CH_(3)OH)^(-1), respectively, for the bare MCF system at 10.1 kV). The findings suggest that inclusion of active metal sites (especially Zn species) could stabilize the CO_(2)/CO-related intermediates to facilitate the surface reaction toward methanol formation.

关键词： non-thermal plasma(NTP)catalysis Cu catalyst CO_(2)hydrogenation methanol siliceous mesocellular foam(MCF)

A Bibliometric Analysis Unveils Valuable Insights into the Past,Present,and Future Dynamics of Plant Acclimation to Temperature

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Phyton-International Journal of Experimental Botany 2024年第2期93卷 291-312页

作者： Yong cui Yongju Zhao Shengnan Ouyang Changchang shao Liangliang Li Honglang Duan Institute for Forest Resources&Environment of Guizhou Key Laboratory of Forest Cultivation in Plateau Mountain of Guizhou ProvinceCollege of ForestryGuizhou UniversityGuiyangChina

Plant temperature acclimation is closely related to maintaining a positive carbon gain under future climate ***,no systematic summary of the field has been *** on this,we analyzed data on plant temperature acclimation from the Web of Science Core Collection database using bibliometric software R,RStudio and *** study demonstrated that a stabilized upward trajectory was noted in publications(298 papers)from 1986 to 2011,followed by a swift growth(373 papers)from 2012 to *** most impactful journals were Plant Cell and Environment,boasting the greatest count of worldwide citations and articles,the highest H-index and G-index,followed by Global Change Biology and New Phytologist,and Frontiers in Plant Science which had the highest *** USA and China were identified as the most influential countries,while Atkin was the most influential author,and the Chinese Academy of Sciences was the most influential research *** most cited articles were published in the Annual Review of Plant Biology in 1999.“Cold acclimation”was the most prominent *** plant temperature acclimation research is expected to focus on thermal acclimation and photosynthesis,which have important significance for future agricultural production,forestry carbon sequestration,and global food *** general,this study provides a systematic insight of the advancement,trend,and future of plant temperature acclimation research,enhancing the comprehension of how plants will deal with forthcoming climate change.

关键词： Temperature acclimation plant responses climate change bibliometric

SIRT1 inhibits apoptosis of human lens epithelial cells through suppressing endoplasmic reticulum stress in vitro and in vivo

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International Journal of Ophthalmology(English edition) 2024年第7期17卷 1205-1216页

作者： hui cui Di Sun Sheng Meng Tian-Ju Ma Zi Ye Zhao-hui Li Medical School of Chinese PLA Beijing 100089China Senior Department of Ophthalmology the Third Medical Center of PLA General HospitalBeijing 100853China

AIM:To explore the effect of silent information regulator factor 2-related enzyme 1(SIRT1)on modulating apoptosis of human lens epithelial cells(HLECs)and alleviating lens opacification of rats through suppressing endoplasmic reticulum(ER)***:HLECs(SRA01/04)were treated with varying concentrations of tunicamycin(TM)for 24h,and the expression of SIRT1 and C/EBP homologous protein(CHOP)was assessed using real-time quantitative polymerase chain reaction(RT-PCR),Western blotting,and *** morphology and proliferation was evaluated using an inverted microscope and cell counting kit-8(CCK-8)assay,*** the SRA01/04 cell apoptosis model,which underwent siRNA transfection for SIRT1 knockdown and SRT1720 treatment for its activation,the expression levels of SIRT1,CHOP,glucose regulated protein 78(GRP78),and activating transcription factor 4(ATF4)were *** potential reversal of SIRT1 knockdown effects by 4-phenyl butyric acid(4-PBA;an ER stress inhibitor)was *** vivo,age-related cataract(ARC)rat models were induced by sodium selenite injection,and the protective role of SIRT1,activated by SRT1720 intraperitoneal injections,was evaluated through morphology observation,hematoxylin and eosin(H&E)staining,Western blotting,and ***:SIRT1 expression was downregulated in TMinduced SRA01/04 ***,in SRA01/04 cells,both cell apoptosis and CHOP expression increased with the rising doses of *** stress was stimulated by TM,as evidenced by the increased GRP78 and ATF4 in the SRA01/04 cell apoptosis *** of SIRT1 by siRNA knockdown increased ER stress activation,whereas SRT1720 treatment had opposite results.4-PBA partly reverse the adverse effect of SIRT1 knockdown on *** vivo,SRT1720 attenuated the lens opacification and weakened the ER stress activation in ARC rat ***:SIRT1 plays a protective role against TM-induced apoptosis in HLECs and slows the progression of cataract in

关键词： silent information regulator factor 2-related enzyme 1 endoplasmic reticulum stress apoptosis human lens epithelial cells cataract