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Improving Radiation Pattern Roundness of Henge-Like Metaring-Loaded Monopoles Above a Finite Ground for MIMO Systems

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Electromagnetic Science 2024年第2期2卷 104-115页

作者： bo Zhang Zhi ning Chen Yucong Zhou Qun Lou Jiahao Wang Koen Mouthaan Department of Electrical and Computer Engineering National University of SingaporeSingapore 117583Singapore Huawei Technologies Co. Ltd.Shenzhen 518129China

A henge-like metaring(HMR)is proposed for improving the radiation pattern roundness of monopole antennas offcenter mounted on a finite ground by localizing the radiation from the monopole and suppressing the scattering by the *** improved patterns enhance uniform coverage of multiple-input and multiple-output(MIMO)*** study reveals that the radiation pattern of an off-center monopole is distorted by the asymmetric ground currents excited by both the feed and the radiation of the *** distorted radiation patterns severely degrade wireless communication link *** HMR,composed of an annular array of mushroom unit cells,simultaneously functions as an electromagnetic bandgap(EBG)and a radiator,and encircles the monopole to form a henge monopole antenna(HMA).The HMR as an EBG is used to suppress the ground currents outside the HMR analyzed by an equivalent circuit *** HMR as a radiator is designed to decouple the monopole from the ground with its elevated radiation pattern using characteristic mode *** examples,two prototypes of single and four off-center MIMO HMAs are designed and investigated in the 2.45-GHz *** and measured results show that the single HMA and each of the four HMAs achieve the un-roundness of the radiation pattern atθ=65°plane lower than 2 dB and 3 dB in the 2.45-GHz *** a result,near the radiation nulls,the SNR is improved by 6 *** compact construction and efficient current suppression facilitate the application of HMAs in multi-antenna systems above a finite ground with uniform coverage and reliable connections.

关键词： Antenna radiation pattern Characteristic mode analysis Metamaterials MIMO communication Omnidirectional antennas Wireless access points

公平竞争审查制度与备案审查制度的衔接机制研究

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西北大学学报（哲学社会科学版） 2024年第4期54卷 140-153页

作者：宁立志龚涛武汉大学法学院湖北武汉430072

公平竞争审查制度与备案审查制度是我国约束规范性文件制发的两种审查制度,但部门法之间的隔阂导致它们在理论上长期割裂。这两种审查制度在监督机制、审查能力、审查动力等方面具有互补性,使得建立它们之间的衔接机制具有现实可能性和... 详细信息

公平竞争审查制度与备案审查制度是我国约束规范性文件制发的两种审查制度,但部门法之间的隔阂导致它们在理论上长期割裂。这两种审查制度在监督机制、审查能力、审查动力等方面具有互补性,使得建立它们之间的衔接机制具有现实可能性和必要性。在坚持公平竞争审查的事前自我审查这一基本定位的前提下,可以将事后审查部分纳入备案审查制度中,将公平竞争审查结论作为备案审查中合法性与适当性审查的参考文件。还可以适时扩张公平竞争审查对象,将部分涉及市场主体经济活动的党组织规范性文件以及人大及其常委会立法、决议和决定纳入公平竞争审查制度,并建立党委、人大、政府之间的公平竞争审查衔接联动机制。

关键词：公平竞争审查备案审查反垄断法合法性审查适当性审查自我审查

A flexible ultra-broadband multi-layered absorber working at 2 GHz-40 GHz printed by resistive ink

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Chinese Physics B 2024年第2期33卷 329-333页

作者：汪涛闫玉伦陈巩华李迎胡俊毛剑波 School of Microelectronics Hefei University of TechnologyHefei 230601China Special Display and Imaging Technology Innovation Center of Anhui Province Academy of Photoelectric TechnologyHefei University of TechnologyHefei 230027China

A flexible extra broadband metamaterial absorber(MMA)stacked with five layers working at 2 GHz–40 GHz is *** layer is composed of polyvinyl chloride(PVC),polyimide(PI),and a frequency selective surface(FSS),which is printed on PI using conductive *** investigate this absorber,both one-dimensional analogous circuit analysis and three-dimensional full-wave simulation based on a physical model are *** crucial electromagnetic properties,such as absorption,effective impedance,complex permittivity and permeability,electric current distribution and magnetic field distribution at resonant peak points,are studied in *** shows that the working frequency of this absorber covers entire S,C,X,Ku,K and Ka bands with a minimum thickness of 0.098λ_(max)(λ_(max) is the maximum wavelength in the absorption band),and the fractional bandwidth(FBW)reaches 181.1%.Moreover,the reflection coefficient is less than-10 dB at 1.998 GHz–40.056 GHz at normal incidence,and the absorptivity of the plane wave is greater than 80%when the incident angle is smaller than 50°.Furthermore,the proposed absorber is experimentally validated,and the experimental results show good agreement with the simulation results,which demonstrates the potential applicability of this absorber at 2 GHz–40 GHz.

关键词： extra broadband physical model flexible metamaterial absorber multi-layer frequency selective surface

考虑环境因素的电动汽车充电站实时负荷预测模型

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同济大学学报（自然科学版） 2024年第6期52卷 962-969页

作者：李波王宁吕叶林陈宇同济大学汽车学院上海201804

为了减少电动汽车大规模集成到电网造成的不利影响,提出了一种能够实现充电站充电负荷精准预测的方法。该方法利用LightGBM(light gradient boosting machine)与XGboost(eXtreme gradient boosting)模型构建线下-线上组合模型。考虑充... 详细信息

为了减少电动汽车大规模集成到电网造成的不利影响,提出了一种能够实现充电站充电负荷精准预测的方法。该方法利用LightGBM(light gradient boosting machine)与XGboost(eXtreme gradient boosting)模型构建线下-线上组合模型。考虑充电负荷、时间、温度、天气等历史数据,利用LightGBM模型初步建立充电负荷线下预测模型;基于XGboost模型,以线下预测模型输出负荷和实际负荷的误差为优化目标,实时变化的交通流量为协变量,建立线上预测模型,并对初步预测结果进行误差修正。某市实际充电站预测结果表明,相比于随机森林(RF)、LightGBM模型、XGboost模型、多层感知机(MLP)以及LightGBM-RF组合模型,该组合模型具有更高的预测精度,同时可以准确预测不同充电站的实时充电负荷。

关键词：电动汽车充电负荷预测 LightGBM(light gradient boosting machine) XGboost(eXtreme gradient boosting) 在线学习

联合国教科文组织全民受教育权工作的实践与挑战

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比较教育学报 2024年第1期 31-43页

作者：胡睿宁波上海师范大学国际与比较教育研究院上海200234 上海师范大学教育决策与大数据实验室上海200234

更加包容、公平、优质的全民终身受教育权是实现2030全球教育发展愿景的关键。联合国教科文组织长期关注全球受教育权事业,经历了以保障人人享有基本的受教育权为重点的起步期、以倡导全民享有终身受教育权为重点的发展期、以追求更加... 详细信息

更加包容、公平、优质的全民终身受教育权是实现2030全球教育发展愿景的关键。联合国教科文组织长期关注全球受教育权事业,经历了以保障人人享有基本的受教育权为重点的起步期、以倡导全民享有终身受教育权为重点的发展期、以追求更加包容、公平、优质的全民终身受教育权为重点的深化期。联合国教科文组织通过制定全球标准、加强各国政府能力建设、开展全球调查研究以及搭建国际合作桥梁等实践路径,切实推进了全球受教育权发展。与此同时,联合国教科文组织全球受教育权工作也面临着弱势群体受教育权缺乏有效保障、数字技术拉大受教育权差距、气候变化加剧受教育权危机等多重挑战。

关键词：受教育权全民终身受教育权联合国教科文组织教育2030

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专利非实施主体的价值评判与法律规制——以网络化开放创新范式为视角

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知识产权 2024年第4期 92-108页

作者：宁立志龚涛武汉大学法学院

在传统视角下,专利非实施主体(NPE)主要产生于知识产权制度的漏洞,它们通过滥诉和滥用禁令救济等方式攫取了不合理的高额利润,会产生阻碍创新、损害消费者利益、破坏市场秩序等消极效果。但实际上,NPE的产生与网络化开放创新密切相关。... 详细信息

在传统视角下,专利非实施主体(NPE)主要产生于知识产权制度的漏洞,它们通过滥诉和滥用禁令救济等方式攫取了不合理的高额利润,会产生阻碍创新、损害消费者利益、破坏市场秩序等消极效果。但实际上,NPE的产生与网络化开放创新密切相关。NPE是知识产权二级市场发展和专业化分工的产物,它在许可谈判中的优势地位很大程度上来自于专利许可模式由事前许可向事后许可的转变。同时,NPE也反过来促进了网络化开放创新。它可以促进技术流动,降低企业获取技术的搜寻成本,提高小企业和个体发明人的创新激励。因此,NPE并没有“原罪”,而是一个中性的市场主体。对NPE的规制思路,应当从基于主体身份的规制路径转变为基于滥用行为及其权利源头的规制路径。

关键词：网络化开放创新非实施主体专利主张实体标准必要专利禁令

Prediction of hepatic artery occlusion after liver transplantation by ultrasound characteristics and clinical risk factors

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World Journal of Radiology 2024年第6期16卷 196-202页

作者： Yu-Ting Lai Yi Chen Tai-Shi Fang Zhi-Yan Li ning-bo Zhao Department of Ultrasound National Clinical Research Centre for Infectious DiseasesThe Third People’s Hospital of ShenzhenThe Second Hospital Affiliated with the Southern University of Science and TechnologyShenzhen 518112Guangdong ProvinceChina Department of Liver Surgery National Clinical Research Centre for Infectious DiseasesThe Third People’s Hospital of ShenzhenThe Second Hospital Affiliated with the Southern University of Science and TechnologyShenzhen 518112Guangdong ProvinceChina

BACKGROUND Hepatic artery occlusion(HAO)after liver transplantation(LT)is a devastating complication,resulting in early graft loss and reduced overall ***-sound is an established assessment method for HAO in patients following LT,especially those with complex hepatic artery *** We retrospectively analyzed the ultrasound characteristics and the clinic risk factors associated with HAO in 400 adult LT patients who were enrolled and treated at the Third People's Hospital of Shenzhen between November 2016 and July *** patients diagnosed with acute HAO(A-HAO)by surgery and fifteen diagnosed with chronic HAO(C-HAO)were included.A control group of 33 patients without HAO complications during the same period were randomly selected using a random number *** patients underwent an ultrasono-graphy *** including resistance index(RI),peak systolic velocity(PSV),and portal vein velocity(PVV)were compared across the ***,basic clinical data were collected for all patients,including gender,age,primary diagnosis,D-dimer concentration,total operation time,cold ischemia time,hot ischemia time,intraoperative blood loss and transfusion,intraoperative urine volume,infusion,model for end-stage liver disease(MELD)score,and whether complex hepatic artery reconstructions were ***,risk factors influencing HAO formation after LT were *** Compared to the non-HAO group,PVV and RI were higher in the A-HAO group,while PSV was ***,both PSV and RI were lower in the C-HAO group compared to the non-HAO *** proportion of patients undergoing complex hepatic artery reconstructions and the gamma-glutamyltransferase(GGT)level before occlusion were significantly higher in the A-HAO group compared to the non-HAO ***,there were no distinct differences between the two groups in D-dimer,MELD score,pre-occlusion alanine transaminase and aspartate transaminase levels,or intrao

关键词： Hepatic artery occlusion Ultrasonography Diagnostic performance Risk factors Liver transplantation

Catalytic Asymmetric Diastereodivergent Synthesis of 2-Alkenylindoles Bearing both Axial and Central Chirality

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Precision Chemistry 2024年第5期2卷 208-220页

作者： Shuang Yang Jia-bo Huang Da-Hua Wang ning-Yi Wang Yu-Yu Chen Xin-Yan Ke Hao Chen Shao-Fei Ni Yu-Chen Zhang Feng Shi Research Center of Chiral Functional Heterocycles School of Chemistry and Materials ScienceJiangsu Normal UniversityXuzhou 221116China Department of Chemistry Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong ProvinceShantou UniversityShantou 515063China Department of Otolaryngology Xuzhou First People’s HospitalAffiliated Xuzhou Municipal Hospital of Xuzhou Medical UniversityXuzhou 221002China School of Petrochemical Engineering Changzhou UniversityChangzhou 213164China

The catalytic asymmetric diastereodivergent synthesis of axially chiral 2-alkenylindoles was established via chiral phosphoric acid-catalyzed addition reactions of C3-unsubstituted 2-alkenylindoles with o-hydroxybenzyl alcohols under different reaction *** this strategy,two series of 2-alkenylindoles bearing both axial and central chirality were synthesized in a diastereodivergent fashion with moderate to high yields and good stereoselectivities(up to 99%yield,95:5 er,>95:5 dr).Moreover,theoretical calculations were performed on the key transition states leading to different stereoisomers,which provided an in-depth understanding of the origin of the observed stereoselectivity and diastereodivergence of the products under different reaction *** importantly,these 2-alkenylindoles were utilized in asymmetric catalysis as chiral organocatalysts and in medicinal chemistry for evaluation of their cytotoxicity,which demonstrated their potential *** study has not only established the catalytic atroposelective synthesis of axially chiral 2-alkenylindoles,but also provided an efficient strategy for catalytic asymmetric diastereodivergent construction of indole-based scaffolds bearing both axial and central chirality.

关键词： 2-Alkenylindole Axial chirality Central chirality Diastereodivergent synthesis Chiral phosphoric acid

一种风电场经VSC-HVDC并网的VSG变参数负荷频率控制策略

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高电压技术 2024年第1期50卷 117-126页

作者：赵熙临龚楚峰付波湖北工业大学电气与电子工程学院武汉430068

风电的大规模并网导致系统等效惯量下降、不确定性增加,给电力系统的负荷频率控制(loadfrequency control,LFC)带来新的挑战。考虑到柔性直流输电系统(voltage source converter based high voltage DC,VSC-HVDC)具有的潜在调频能力,对... 详细信息

风电的大规模并网导致系统等效惯量下降、不确定性增加,给电力系统的负荷频率控制(loadfrequency control,LFC)带来新的挑战。考虑到柔性直流输电系统(voltage source converter based high voltage DC,VSC-HVDC)具有的潜在调频能力,对此展开研究,针对风电场经VSC-HVDC并网的情形提出了一种虚拟同步发电机(virtual synchronous generator,VSG)变参数负荷频率控制策略。首先,在风电场经VSC-HVDC并网的LFC模型及拓扑结构分析基础上,为了提高VSC-HVDC的可控性,对换流器的控制环节进行了VSG控制方法的设计;然后,对VSG控制参数与频率变化的关联性进行分析,并基于分数阶梯度下降法(fractional-order gradient descent method,FOGDM),利用频率的分数阶导数提取频率深层变化特征,以优化VSG控制参数;在此基础上,考虑到系统的不确定性,设计触发机制对VSG变参数优化模式进行调整,以降低VSG参数的变换频次,提高系统频率控制的针对性。仿真结果表明:所提控制方法能有效改善电网负荷频率控制效果,具有良好的适应性。

关键词：负荷频率控制虚拟同步发电机风电柔性直流输电系统分数阶参数优化