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

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

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Characteristics of Particulate Matter Emissions for Low-Sulfur Heavy Oil Used in Low-Speed Two-Stroke Diesel Engines of Ocean-Going Ships

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Journal of Thermal Science 2024年第2期33卷 739-750页

作者： WU Gang MA Qianli wei Lijiang JIANG Guohe WANG Tengfei LI tie Merchant Marine College Shanghai Maritime UniversityShanghai201306China State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai200240China

In this work,particulate matter(PM) emissions from a large two-stroke,low-speed marine diesel engine were investigated when the engine was operated with low-sulfur heavy fuel oil(HFO) at various *** samples were collected in situ from the engine exhaust to determine the detailed physical and chemical *** nanostructure and morphology of the nanoparticles were analyzed using transmission electron microscopy images(TEM).The results show that volatile organic carbon(OC) accounts for more than 80% in the HFO particles and leads to an increase in particle *** thermodynamic conditions of a low-speed engine favor the behavior of capturing the soluble organic components.A large number of spherical char HFO particles with aerodynamic diameters of 0.2 μm-0.5 μm and a suspected inner metal core were *** two peak aerodynamic diameters of the HFO nanoparticles are 15 nm and 86 *** morphological differences among the HFO nanoparticles in varied engine conditions represent the formation process from primary nascent particles to mature graphitized particles caused by *** above study will be valuable for understanding the characteristics of PM emissions from low-sulfur HFO to achieve the ship PM emissions reduction target.

关键词： low-speed diesel engine maritime regulations heavy fuel oil TEM particles size and distribution

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Machine learning-based performance predictions for steels considering manufacturing process parameters:a review

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Journal of Iron and Steel Research(International) 2024年第7期31卷 1555-1581页

作者： wei Fang Jia-xin Huang tie-xu Peng Yang Long Fu-xing Yin Tianjin Key Laboratory of Materials Laminating Fabrication and Interface Control Technology School of Materials Science and EngineeringHebei University of TechnologyTianjin 300132China Institute of New Materials Guangdong Academy of ScienceGuangzhou 510651GuangdongChina

Steels are widely used as structural materials,making them essential for supporting our lives and ***,further improving the comprehensive properties of steel through traditional trial-and-error methods becomes challenging due to the continuous development and numerous processing parameters involved in steel *** address this challenge,the application of machine learning methods becomes crucial in establishing complex relationships between manufacturing processes and steel *** review begins with a general overview of machine learning methods and subsequently introduces various performance predictions in steel *** classification of performance pre-diction was used to assess the current application of machine learning model-assisted *** important issues,such as data source and characteristics,intermediate features,algorithm optimization,key feature analysis,and the role of environmental factors,were summarized and *** insights will be beneficial and enlightening to future research endeavors in this field.

关键词： Steel Manufacturing process Machine learning Performance prediction Algorithm

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Novel limited feedback scheme under the MIMO broadcast system

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The Journal of China Universities of Posts and Telecommunications 2009年第6期16卷 11-16页

作者： CHENG tie-zheng,YUAN Chao-wei School of Information and Communication Engineering,Beijing University of Posts and Telecommunications,Beijing 100876,China School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

By deducing the distribution of the normalized channel covariance matrix,a novel limited feedback scheme is proposed under multiple users（MU） multiple-input multiple-output（MIMO） broadcast channel（BC） *** proposed scheme has advantages in three ***,it has no constraints on the number of users or ***,each user＇s feedback bits are independent of the number of receiving ***,the proposed scheme avoids the storage of large-size codebook on the *** results show that the performance of the proposed scheme is close to the perfect channel state information（CSI） case and it just needs a small number of feedback bits.

关键词： MIMO broadcast channel limited feedback normalized channel covariance

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{1012}twin–twin intersection-induced lattice rotation and dynamic recrystallization in Mg–6Al–3Sn–2Zn alloy

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Journal of Magnesium and Alloys 2024年第4期12卷 1529-1539页

作者： Bin-Jiang Lv Sen Wang Fu-Hao Gao Ning Cui Yi-Nan Li tie-wei Xu Feng Guo School of Mechanical and Automotive Engineering Qingdao University of Technology266520China Key Lab of industrial Fluid Energy Conservation and Pollution Control Qingdao University of Technology266520China

This study investigated the formation mechanism of new grains due to twin–twin intersections in a coarse-grained Mg–6Al–3Sn–2Zn alloy during different strain rates of an isothermal *** results of electron backscattered diffraction investigations showed that the activated twins were primarily{1012}tension twins,and 60°boundaries formed due to twin–twin intersections under different strain *** twin variants with 60°boundaries transformed into new grains through lattice rotations at a low strain rate(0.01 s^(−1)).At a high strain rate(10 s^(−1)),the regions surrounded by subgrain boundaries through high-density dislocation arrangement and the 60°boundaries transformed into new grains via dynamic recrystallization.

关键词： Mg alloy Twin-twin intersection Lattice rotation Dynamic recrystallization

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“两个结合”视域下习近平生态文明思想的创新发展

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国家林业和草原局管理干部学院学报 2024年第2期23卷 18-24页

作者：王维铁铮北京林业大学北京100083

习近平生态文明思想的形成既深受马克思主义生态理论的影响,又紧密结合了中国的具体实际,汲取了中华优秀传统文化的精髓。在这一思想中,“山水林田湖草沙是生命共同体”的整体系统观,既是对马克思物质变换理论的基本遵循,也是对中国传... 详细信息

习近平生态文明思想的形成既深受马克思主义生态理论的影响,又紧密结合了中国的具体实际,汲取了中华优秀传统文化的精髓。在这一思想中,“山水林田湖草沙是生命共同体”的整体系统观,既是对马克思物质变换理论的基本遵循,也是对中国传统“万物一体”整体观的创新发展;“人与自然生命共同体”的科学自然观,是对马克思主义人与自然关系理论的基本遵循,也是对中国传统“天人合一”自然观的创新发展;“绿水青山就是金山银山”的绿色发展观,是对马克思主义“两个和解”思想的时代阐释,也是对中国传统的“取用有度”观念的创新发展。这一思想体系的形成,为中国生态文明建设提供了坚实的理论基础和实践指导。

关键词：两个结合习近平生态文明思想马克思主义生态理论中华优秀传统文化

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The transgenerational effects of maternal low-protein diet during lactation on offspring

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Journal of Genetics and Genomics 2024年第8期51卷 824-835页

作者： Lin-Jian Gu Li Li Qian-Nan Li Ke Xu wei Yue Jing-Yi Qiao tie-Gang Meng Ming-Zhe Dong Wen-Long Lei Jia-Ni Guo Zhen-Bo Wang Qing-Yuan Sun State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Institute of Laboratory Animal Sciences CAMS&PUMCBeijing 100021China Guangzhou Key Laboratory of Metabolic Diseases and Reproductive Health Guangdong-Hong Kong Metabolism&Reproduction Joint LaboratoryReproductive Medicine CenterGuangdong Second Provincial General HospitalGuangzhouGuangdong 510317China

Environmental factors such as diet and lifestyle can influence the health of both mothers and ***,its transgenerational transmission and underlying mechanisms remain largely ***,using a maternal lactation-period low-protein diet(LPD)mouse model,we show that maternal LPD during lactation causes decreased survival and stunted growth,significantly reduces ovulation and litter size,and alters the gut microbiome in the female LPD-F1 *** transcriptome of LPD-F1 metaphase II(MII)oocytes shows that differentially expressed genes are enriched in female pregnancy and multiple metabolic ***,maternal LPD causes early stunted growth and impairs metabolic health,which is transmitted over two *** methylome alteration of LPD-F1 oocytes can be partly transmitted to the F2 ***,our results reveal that LPD during lactation transgenerationally affects offspring health,probably via oocyte epigenetic changes.

关键词： Lactationdiet Maternal low-proteindiet DNAmethylation Transgenerational effect Oocyte

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基于水动力水质模型的浅水型湖泊水环境治理目标可达性评估

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给水排水 2024年第2期50卷 65-71页

作者：毛毅饶世雄陈铁江山范乐魏征武汉市政工程设计研究院有限责任公司武汉430023 武汉市海绵城市和综合管廊建设管理站武汉430023

当前湖泊水环境治理仍然面临着湖泊水质的实际改善效果与工程方案预期不相符的难题,特别是城市浅水型湖泊,其受外源污染、底泥释放、降雨冲击等因素,对治理成效扰动响应更为剧烈,因此,进行多因素成效评估对城市浅水型湖泊水环境治理尤... 详细信息

当前湖泊水环境治理仍然面临着湖泊水质的实际改善效果与工程方案预期不相符的难题,特别是城市浅水型湖泊,其受外源污染、底泥释放、降雨冲击等因素,对治理成效扰动响应更为剧烈,因此,进行多因素成效评估对城市浅水型湖泊水环境治理尤为重要。采用InfoWorks ICM模型,以武汉市墨水湖为例,搭建浅水型湖泊水质水动力模型,依据气象水文、城市开发建设、湖泊污染情况等现状数据,基于模型计算原理,研究COD、NH_(3)-N、TP等污染物的变化趋势,定量分析不同工况情景下湖泊水质的可达性,评估规划拟建工程的实施效果,可为同类湖泊水环境治理工程方案优化提供参考。

关键词：水环境治理浅水型湖泊目标可达性评估水动力水质模型

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Establishment of a Multiplex Detection Method for Common Bacteria in Blood Based on Human Mannan-Binding Lectin Protein-Conjugated Magnetic Bead Enrichment Combined with Recombinase-Aided PCR Technology

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Biomedical and Environmental Sciences 2024年第4期37卷 387-398页

作者： ZHAO Zi Jin CHEN Xiao Ping HUA Shao wei LI Feng Yu ZHAO Meng XING Chen Hao WANG Jie TIAN Feng Yu ZHANG Rui Qing LYU Xiao Na HAN Zhi Qiang WANG Yu Xin LI Hong Yi SHEN Xin Xin MA Xue Jun tie Yan Qing Graduate School Hebei North UniversityZhangjiakou 075000HebeiChina Department of Clinical Laboratory Hebei General HospitalShijiazhuang 050051HebeiChina National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases NHC Key Laboratory of Medical Virology and Viral DiseasesNational Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 102206China National Institute for Communicable Disease Control and Prevention Chinese Center for Disease Control and PreventionBeijing 102206China Department of Clinical Laboratory Pathology Diagnostic Center Shiyan General HospitalShiyan 442000HubeiChina Graduate School Hebei Medical University Shijiazhuang 050031HebeiChina

Objective Recombinase-aided polymerase chain reaction(RAP)is a sensitive,single-tube,two-stage nucleic acid amplification *** study aimed to develop an assay that can be used for the early diagnosis of three types of bacteremia caused by Staphylococcus aureus(SA),Pseudomonas aeruginosa(PA),and Acinetobacter baumannii(AB)in the bloodstream based on recombinant human mannanbinding lectin protein(M1 protein)-conjugated magnetic bead(M1 bead)enrichment of pathogens combined with *** Recombinant plasmids were used to evaluate the assay *** blood influenza bacteria were used for the specific *** and clinical plasma samples were enriched with M1 beads and then subjected to multiple recombinase-aided PCR(M-RAP)and quantitative PCR(qPCR)*** analysis was used to evaluate the consistency between the two *** The M-RAP method had sensitivity rates of 1,10,and 1 copies/μL for the detection of SA,PA,and AB plasmids,respectively,without cross-reaction to other bacterial *** M-RAP assay obtained results for<10 CFU/mL pathogens in the blood within 4 h,with higher sensitivity than qPCR.M-RAP and qPCR for SA,PA,and AB yielded Kappa values of 0.839,0.815,and 0.856,respectively(P<0.05).Conclusion An M-RAP assay for SA,PA,and AB in blood samples utilizing M1 bead enrichment has been developed and can be potentially used for the early detection of bacteremia.

关键词： Staphylococcus aureus Pseudomonas aeruginosa Acinetobacter baumannii Human Mannan-binding lectin protein Bloodstream infection Recombinase-aided PCR assay Multiple detection

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Pulse repetition rate effect on the plasma inside femtosecond laser filament in air

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Chinese Optics Letters 2024年第1期22卷 135-140页

作者：尹富康王铁军刘尧香龙娟魏迎霞朱斌周凯南冷雨欣 State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine Mechanics and CAS Center for Excellence in Ultra-intense Laser ScienceChinese Academy of SciencesShanghai 201800China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Laser Fusion Research Center and Science&Technology on Plasma Physics Laboratory China Academy of Engineering PhysicsMianyang 621999China

The characteristics of plasmas play an important role in femtosecond laser filament-based *** analysis is used to experimentally investigate the plasma density and its temperature of the air filament under different pulse repetition *** our experiments,the measured average plasma density of the filament is 1.54×10^(17)cm^(-3)and the temperature of the plasma is about 5100 K under 100 Hz pulse repetition *** plasma density decreases to1.43×10^(17)cm^(-3)and the temperature increases to 6230 K as the pulse repetition rate increases to 1000 *** experimental observation agrees with the numerical simulation by solving the nonlinear Schr?dinger equations with repetition rate related“low density hole”correction.

关键词： femtosecond laser filamentation cumulative effects electron density

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