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低轨卫星激光载荷配置及快速建链方法的研究

激光技术 2024年第2期48卷 249-254页

作者：张世层张冬王平安绍毅高鹏孙艳红西安电子科技大学通信工程学院西安710071 中国电子科技集团公司第五十四研究所石家庄050081

为了适应未来低轨卫星轻量化和低成本的发展趋势,满足星间激光快速建链的使用需求,对星间激光配置原则进行了分析,采用转台式激光载荷和固定式激光载荷相结合的载荷配置方式,分别用于异轨道面间和同轨道面内的星间建链,设计了基于在轨... 详细信息

为了适应未来低轨卫星轻量化和低成本的发展趋势,满足星间激光快速建链的使用需求,对星间激光配置原则进行了分析,采用转台式激光载荷和固定式激光载荷相结合的载荷配置方式,分别用于异轨道面间和同轨道面内的星间建链,设计了基于在轨恒星标校、信标光辅助建链和光轴一致性的激光载荷快速星间建链方案,并介绍了全流程。结果表明,星间激光载荷建链时间小于30 s,可实现长时间的星间激光稳定跟踪通信。该研究结果有助于推动星间激光通信的发展和大规模在轨应用。

关键词：光通信快速激光建链激光在轨标校信标光

Peanut-Like Hematite Prepared by a New Facile Hydrothermal Process for Removal of As(V)

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Transactions of Tianjin University 2019年第1期25卷 23-30页

作者： Chengjin Zhang shaoyi Jia Songhai Wu Yong Liu School of Chemical Engineering and Technology Tianjin University School of Chemistry and Chemical Engineering Tianjin University of Technology

Peanut-like hematite has been prepared by a new facile hydrothermal method and applied in the adsorption removal of As(V). The structural features of the as-prepared hematite were characterized systematically by X-ray diffraction, X-ray photoelectron spectroscopy, Brunauer–Emmett–Teller, scanning electron microscopy, energy-dispersive X-ray spectroscopy mapping, Fourier transform infrared spectroscopy, and transmission electron microscopy. Results showed that the morphologies of hematite could be tuned to spindle-like, oval-like, and cantaloupe-like shapes by adjusting the hydrothermal conditions. The peanut-like hematite formation followed a five-step route. At pH = 3, the adsorption amount of As(V) over peanut-like hematite reached 13.84 mg/g, and the adsorption kinetic process corresponded to the pseudo-second-order kinetic model. The peanut-like hematite also showed partial selectivity over As(V) in the hydrosphere. This method can be a reference for the preparation of other architectural metal oxide materials.

关键词： Peanut-like hematite Arsenic adsorbent Nanoparticle

钆塞酸二钠增强MRI对单发肝细胞癌微血管侵犯的预测价值

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临床放射学杂志 2024年第4期43卷 597-604页

作者：王少怡周智鹏蒋宇林斌方行李晨王玲廷刘蒋静桂林医学院附属医院放射科

目的探讨临床资料、基于钆塞酸二钠(Gd-EOB-DTPA)增强MRI的影像征象及影像组学方法对单发肝细胞癌(HCC)患者微血管侵犯(MVI)的单独及联合预测价值。方法 110例HCC患者(训练集:77例,验证集:33例),分析入组患者的临床资料,评估MRI影像征... 详细信息

目的探讨临床资料、基于钆塞酸二钠(Gd-EOB-DTPA)增强MRI的影像征象及影像组学方法对单发肝细胞癌(HCC)患者微血管侵犯(MVI)的单独及联合预测价值。方法 110例HCC患者(训练集:77例,验证集:33例),分析入组患者的临床资料,评估MRI影像征象,并分别从动脉期、门静脉期和延迟期3个序列中提取瘤内影像组学特征,使用最小绝对收缩和选择算子(LASSO)算法进行特征选择,随后使用Logistic回归分析构建临床模型、影像征象模型、单序列影像组学模型、影像组学联合模型和临床-影像征象-影像组学模型,并评估不同模型的性能。结果 110例患者中,48例(43.6%)经病理证实存在MVI。在训练集中,年龄在MVI状态方面差异有统计学意义(P<0.05)。在训练集及验证集中,γ-谷氨酰转肽酶(γ-GT)、动脉期瘤周强化、肝胆期瘤周低信号都是MVI的有力预测因子(P<0.05)。通过LASSO算法,最终选择了17个与MVI相关的影像组学特征。在3个单序列影像组学模型中,基于门静脉期图像建立的影像组学模型对HCC患者MVI的预测能力表现最佳,其在训练集和验证集中的曲线下面积(AUC)分别为0.788、0.699。最终构建的临床-影像征象-影像组学模型在训练集中表现出较高的效能,相应AUC为0.895(95%CI:0.827~0.963),特异度为0.744,敏感度为0.912。结论本研究建立了一种基于患者临床资料,Gd-EOB-DTPA增强MRI的影像征象及影像组学多个序列特征的联合模型,并验证了其在术前无创预测HCC患者MVI的价值,其有可能作为指导后续个体化治疗的临床工具。

关键词：肝细胞癌微血管侵犯磁共振成像钆塞酸二钠影像组学

A Correntropy-based Affine Iterative Closest Point Algorithm for Robust Point Set Registration

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IEEE/CAA Journal of Automatica Sinica 2019年第4期6卷 981-991页

作者： Hongchen Chen Xie Zhang shaoyi Du Zongze Wu Nanning Zheng the School of Electronic and Information Engineering South China University of TechnologyGuangzhou 510640China the School of Electric Power South China University of TechnologyGuangzhou 510640China the Institute of Artificial Intelligence and Robotics Xi’an Jiaotong UniversityXi’an 710049China the School of Automation Guangdong University of TechnologyGuangzhou 510006China IEEE

The iterative closest point(ICP)algorithm has the advantages of high accuracy and fast speed for point set registration,but it performs poorly when the point set has a large number of noisy *** solve this problem,we propose a new affine registration algorithm based on correntropy which works well in the affine registration of point sets with ***,we substitute the traditional measure of least squares with a maximum correntropy criterion to build a new registration model,which can avoid the influence of *** maximize the objective function,we then propose a robust affine ICP *** each iteration of this new algorithm,we set up the index mapping of two point sets according to the known transformation,and then compute the closed-form solution of the new transformation according to the known index *** to the traditional ICP algorithm,our algorithm converges to a local maximum monotonously for any given initial ***,the robustness and high efficiency of affine ICP algorithm based on correntropy are demonstrated by 2D and 3D point set registration experiments.

关键词： Affine iterative closest point(ICP)algorithm correntropy-based robust point set registration

福州市男男性行为人群商业同性性行为特征及无保护肛交的相关因素分析

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中华流行病学杂志 2024年第9期45卷 1233-1238页

作者：张宏陈剑惠何鼎盛薛洪洪林春仲许绍溢福建医科大学附属福州市疾病预防控制中心艾滋病防治科福州福建省性病艾滋病防治志愿者协会福州

目的分析MSM商业同性性行为特征及无保护肛交(UAI)的相关因素, 为制定MSM干预措施提供参考依据。方法研究对象为≥16岁男性且最近6个月发生同性肛交行为者, 于2023年1-12月在福州市通过网络方式招募研究对象, 根据横断面研究设计估计样... 详细信息

目的分析MSM商业同性性行为特征及无保护肛交(UAI)的相关因素, 为制定MSM干预措施提供参考依据。方法研究对象为≥16岁男性且最近6个月发生同性肛交行为者, 于2023年1-12月在福州市通过网络方式招募研究对象, 根据横断面研究设计估计样本量为283人。采用多因素logistic 回归模型分析研究对象最近6个月发生UAI的相关因素。采用SPSS 25.0软件进行统计学分析。结果在调查的MSM 4 484人中, 发生商业同性性行为的比例为9.59%(430/4 484), 年龄(27.00±9.07)岁。在发生商业同性性行为的MSM中, 最近1周发生肛交的比例为70.00%(301/430), 最近6个月发生肛交的性伴数>10人的比例为43.02%(185/430)。最近6个月发生UAI的比例为75.58%(325/430)。多因素分析结果表明, 在最近6个月发生商业同性性行为的MSM中, 相比于学生、首次发生性行为年龄>18岁、最近1周未发生肛交和最近6个月发生肛交性伴数≤10人者, 非学生(aOR=1.99, 95%CI:1.18～3.36)、首次发生性行为年龄≤18岁(aOR=2.04, 95%CI:1.26～3.29)、最近1周发生肛交(aOR=2.04, 95%CI:1.25～3.33)和最近6个月发生肛交性伴数>10人者(aOR=1.97, 95%CI:1.16～3.35)发生UAI的风险较高。结论福州市发生商业同性性行为的MSM中发生UAI风险较高, 应针对该人群加强以提高安全性行为的认知、倡导固定性伴、坚持使用安全套和预防药物滥用为主的干预措施。

关键词：艾滋病病毒男男性行为人群商业同性性行为无保护肛交

An Efficient Federated Learning Framework Deployed in Resource-Constrained IoV:User Selection and Learning Time Optimization Schemes

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China Communications 2023年第12期20卷 111-130页

作者： Qiang Wang shaoyi Xu Rongtao Xu Dongji Li School of Electronics and Information Engineering Beijing Jiaotong UniversityBeijing 100044China National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China

In this article,an efficient federated learning(FL)Framework in the Internet of Vehicles(IoV)is *** the considered model,vehicle users implement an FL algorithm by training their local FL models and sending their models to a base station(BS)that generates a global FL model through the model *** each user owns data samples with diverse sizes and different quality,it is necessary for the BS to select the proper participating users to acquire a better global ***,considering the high computational overhead of existing selection methods based on the gradient,the lightweight user selection scheme based on the loss decay is *** to the limited wireless bandwidth,the BS needs to select an suitable subset of users to implement the FL ***,the vehicle users’computing resource that can be used for FL training is usually limited in the IoV when other multiple tasks are required to be *** local model training and model parameter transmission of FL will have significant effects on the latency of *** address this issue,the joint communication and computing optimization problem is formulated whose objective is to minimize the FL delay in the resource-constrained *** solve the complex nonconvex problem,an algorithm based on the concave-convex procedure(CCCP)is proposed,which can achieve superior performance in the small-scale and delay-insensitive FL *** to the fact that the convergence rate of CCCP method is too slow in a large-scale FL system,this method is not suitable for delay-sensitive *** solve this issue,a block coordinate descent algorithm based on the one-step projected gradient method is proposed to decrease the complexity of the solution at the cost of light performance *** are conducted and numerical results show the good performance of the proposed methods.

关键词： block coordinate descent concave-convex procedure federated learning learning time resource allocation

Boron-doped Covalent Triazine Framework for Efficient CO_(2) Electroreduction

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Chemical Research in Chinese Universities 2022年第1期38卷 141-146页

作者： YI Jundong LI Qiuxia CHI shaoyi HUANG Yuanbiao CAO Rong College of Chemistry Fuzhou UniversityFuzhou 350108P.R.China Institute of New Materials&Industry Technology Wenzhou UniversityWenzhou 325027P.R.China School of Chemistry and Materials Science Collaborative Innovation Center of Chemistry for Energy Materials(iChEM)University of Science and Technology of ChinaHefei 230026P.R.China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350025P.R.China University of the Chinese Academy of Sciences Beijing 100049P.R.China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108P.R.China

Converting CO_(2) into chemicals with electricity generated by renewable energy is a promising way to achieve the goal of carbon neutrality. Carbon-based materials have the advantages of low cost, wide sources and environmental friendliness. In this work, we prepared a series of boron-doped covalent triazine frameworks and found that boron doping can significantly improve the CO selectivity up to 91.2% in the CO_(2) electroreduction reactions(CO_(2)RR). The effect of different doping ratios on the activity by adjusting the proportion of doped atoms was systematically investigated. This work proves that the doping modification of non-metallic materials is a very effective way to improve their activity, and also lays a foundation for the study of other element doping in the coming future.

关键词： Covalent triazine framework CO_(2)electroreduction CO B-doping

Thermoelectric Properties of an Individual suspended Single-Crystalline Sb_(2)Se_(3)Nanowire

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Journal of Thermal Science 2022年第4期31卷 1106-1114页

作者： DU Yanzheng SHI shaoyi MIAO Tingting MA Weigang MAI Liqiang ZHANG Xing Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Engineering Mechanics Tsinghua UniversityBeijing 100084China Beijing Key Laboratory of Process Fluid Filtration and Separation College of Mechanical and Transportation EngineeringChina University of PetroleumBeijing 102249China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan430070China

Nanowires exhibit excellent thermoelectric performance,due to the stronger quantum confinement and phonon scattering effect compared to bulk ***,it is a challenge to accurately evaluate the thermoelectric performance of *** this paper,the thermoelectric properties of an individual suspended Sb_(2)Se_(3) nanowire have been characterized by comprehensive T-type method,including thermal conductivity,electrical conductivity,Seebeck coefficient and figure of *** thermal conductivity increases from 0.57 W/(m·K)to 3.69 W/(m·K)with temperature increasing from 80 K to 320 *** lattice vibration dominates the heat conduction process,and due to its flawless crystal structure,the thermal conductivity is not lower than the reported values of bulk Sb_(2)Se_(3).The electrical conductivity increases from 7.83 S/m to 688 S/m in the temperature range of 50 K–320 K,which is a great improvement compared with the corresponding bulk *** 294 K,the Seebeck coefficient of the Sb_(2)Se_(3) nanowire is–1120μV/K and the corresponding figure of merit is 0.064.

关键词： Sb_(2)Se_(3)nanowire thermoelectric properties thermal conductivity Seebeck coefficient electrical conductivity

THE CONVERGENCE OF NONHOMOGENEOUS MARKOV CHAINS IN GENERAL STATE SPACES BY THE COUPLING METHOD

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Acta Mathematica Scientia 2021年第5期41卷 1777-1787页

作者： Zhifeng ZHU shaoyi ZHANG Fanji TIAN School of Mathematics and Statistics Hubei Engineering UniversityXiaogan 432000China Hubei Province Key Laboratory of Systems Science in Metallurgical Process(Wuhan University of Science and Technology) Wuhan 430081China Hubei Key Laboratory of Applied Mathematics School of Mathematics and StatisticsHubei UniversityWuhan 430062China

We investigate the convergence of nonhomogeneous Markov chains in general state space by using the f norm and the coupling method,and thus,a sufficient condition for the convergence of nonhomogeneous Markov chains in ... 详细信息

关键词： f norm coupling nonhomogeneous Markov chains convergence