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China Ocean Engineering 2022年第6期36卷 933-946页

作者： YAO Yu WU Ji LI jiang-xia CHEN Long School of Hydraulic and Environmental Engineering Changsha University of Science and TechnologyChangsha 410114China Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province Changsha 410114China

Wave-driven circulation in a reef-lagoon-channel system has significant ecological,geomorphological,and environmental ***,there is still research gap in fully understanding the responses of wave-driven circulation in the system to varying incident wave forcing and reef *** better interpret the wave-current process inside an idealized reef-lagoon-channel configuration,a numerical model based on the horizontally two-dimensional(2DH)fully nonlinear Boussinesq equations is presented in this *** adopted model is firstly validated by a published laboratory dataset for wave height,wave setup and mean current in the ***,the impacts of wave forcing(incident wave height,incident wave period,reef-flat wave level)and reef morphological(fore-reef slope,cross-shore reef-flat width,channel width,reef roughness)factors that are not fully considered in the previous laboratory studies are reported through the numerical simulations in this ***,the model is applied to analyze the wave pump efficiency parameter in the system,and an empirical equation to predict this parameter is also proposed.

关键词： wave-induced setup circulation cell coral reef wave pump efficiency Boussinesq equations

2016-2022年江苏省常州市禽类相关外环境禽流感病毒监测分析

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疾病监测 2024年第1期39卷 43-47页

作者：郑献智甄茜蒋霞姚萍程凯丽陈聪常州市疾病预防控制中心江苏常州213000 南京医科大学公共卫生学院江苏南京211103

目的对2016—2022年江苏省常州市禽类相关外环境标本病毒检测结果进行分析,了解禽流感病毒的流行特征,为常州市禽流感防控工作提供科学依据。方法采用实时荧光定量聚合酶链式反应方法对标本进行禽流感病毒核酸检测,采用描述性流行病学... 详细信息

目的对2016—2022年江苏省常州市禽类相关外环境标本病毒检测结果进行分析,了解禽流感病毒的流行特征,为常州市禽流感防控工作提供科学依据。方法采用实时荧光定量聚合酶链式反应方法对标本进行禽流感病毒核酸检测,采用描述性流行病学方法对检测结果进行统计分析。结果2016—2022年共采集禽流感外环境标本3142份,共检测出甲型流感病毒核酸阳性标本493份,阳性率15.69%,阳性标本以H9亚型为主,占82.76%。冬春季外环境中禽流感病毒阳性检出率较高,H7亚型及其混合型阳性检出率在2016年冬季出现一次高峰,且与人感染H7亚型禽流感病例数呈正相关(r=0.832,P=0.020)。新北区阳性检出率最高(26.32%),溧阳市最低(8.09%)。不同类型监测场所禽流感病毒阳性检出率差异有统计学意义(χ^(2)=123.587,P<0.001),城乡活禽市场标本阳性检出率最高(20.07%),野生禽鸟栖息地最低(未检出阳性标本);不同类型外环境标本中禽流感病毒阳性检出率差异有统计学意义(χ^(2)=56.830,P<0.001),宰杀或摆放禽肉案板表面的擦拭标本中禽流感病毒阳性检出率最高(21.29%),咽/肛拭子或粪便标本阳性检出率最低(10.37%)。结论常州市外环境中的禽流感病毒以H9亚型为主。应将城乡活禽市场作为禽流感防控重点场所,加强冬春季禽流感病毒监测力度。

关键词：禽流感病毒禽类相关外环境监测

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融合粒度划分的回归标签噪声过滤方法

小型微型计算机系统 2024年第8期45卷 1832-1838页

作者：史颖祁晓博亓慧姜高霞王文剑太原师范学院计算机科学与技术学院山西晋中030619 山西大学计算机与信息技术学院太原030006 山西大学智能信息处理研究所太原030006 山西警察学院网络安全保卫系太原030401

机器学习算法的性能与数据质量密切相关,然而实际数据中可能存在各类噪声,如何处理标签噪声是机器学习的重要挑战之一.由于回归标签噪声的复杂性,现有噪声过滤方法在处理数值型标签噪声时效果不够理想.本文首先通过标签离散化方式提出... 详细信息

机器学习算法的性能与数据质量密切相关,然而实际数据中可能存在各类噪声,如何处理标签噪声是机器学习的重要挑战之一.由于回归标签噪声的复杂性,现有噪声过滤方法在处理数值型标签噪声时效果不够理想.本文首先通过标签离散化方式提出一种基于粒度球的数值型标签噪声估计方法,然后给出标签含噪时回归模型的泛化误差估计,并将其作为噪声过滤的目标函数进行优化,最后将所提噪声估计方法与目标函数结合设计了粒度球标签噪声过滤(Granular Ball Label Noise Filtering,GBNF)方法.在标准数据集和真实年龄估计数据集的实验结果表明,该方法识别标签噪声的准确率较高,并取得了比其他噪声过滤比较方法更好的测试性能.

关键词：回归标签噪声粒度球噪声过滤

Generation of W-Type Entangled Coherent States of Three-Cavity Fields by a Driving Classical Field

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Communications in Theoretical Physics 2006年第2X期46卷 303-305页

作者： CHEN Mei-Feng jiang xia-Ping Department of Electronic Science and Applied Physics Fuzhou University Fuzhou 350002 China

A scheme is proposed to generate the W-type entangled coherent states of three-cavity field. The scheme is based on the resonant atom-field interaction, thus the interaction time between the atom and the cavity is greatly reduced, which is important in view of decoherence. Furthermore, the scheme does not need accurate adjustment of the interaction time.

关键词： resonant interaction driving classical field W-type entangled coherent states

Reduction of SO2 to elemental sulfur over rare earth-iron catalysts

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Journal of Rare Earths 2009年第5期27卷 744-748页

作者： DENG Gengfeng jiang Kun CAO xia LIAO Chunfa School of Materials and Chemical Engineering Jiangxi University of Science and Technology Ganzhou 341000 China School of Materials and Chemical Engineering Jiangxi University of Science and Technology Ganzhou 341000 China Nanchang Engineering and Research Institute of Nonferrous Metals Nanchang 330000 China School of Materials and Chemical Engineering Jiangxi University of Science and Technology Ganzhou 341000 China

With coal gas as a reducing agent, the catalytic reduction of SO2 to sulfur in the flue gas produced in metallurgical processes was studied over catalysts of rare earth-Fe/Al2O3 (REFe/Al2O3). The catalytic activity of the REFe/Al2O3 catalyst on the reduction of SO2 to sul-fur was investigated based on kinds and the contents of rare earths and different preparation method of the catalyst. Additionally, the mecha-nism of this catalytic reduction reaction was also explored. Results showed that different rare earth imposed different effect on the activity of the Fe/Al2O3 catalyst. Especially, the addition of Sm and Dy greatly improved the catalytic activity of Fe/Al2O3. The yield of sulfur over SmFe/Al2O3was increased to 86.62% at 360 ℃, which was 40.5% higher than that over Fe/Al2O3at the same temperature; and the sulfur yield over DyFe/Al2O3was increased to 91.62% at 400 ℃, 26.4% higher than that over Fe/Al2O3. The catalytic activity of REFe/Al2O3 was somehow dependent on the content of rare earth. For SmFe/Al2O3, the content of Sm was optimized to be about 1.0 wt.%. The rare earth catalyst prepared with different methods also showed varied activity. The sulfur yield over rare-earth transition metal catalysts follows the order: Sm and iron solution mixing impregnationSm first, then iron solution impregnationiron first, then Sm solution impregnation. The reaction mechanism of SO2 reduction to sulfur with coal gas was proposed to be an intermediate mechanism.

关键词： sulfur dioxide catalytic reduction sulfur flue gas rare earths

A new principle and device for large aircraft components gaining accurate support by ball joint

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第5期12卷 405-414页

作者： Bao-gui QIU Jun-xia jiang Ying-lin KE The State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China

How to obtain an accurate support for large components by ball joint is a key process in aircraft digital assembly. A novel principle and device is developed to solve the problem. Firstly, the working principle of the device is introduced. When three or four displacement sensors installed in the localizer are touched by the ball-head, the spatial relation is calculated between the large aircraft component's ball-head and the localizer's ball-socket. The localizer is driven to achieve a new position by compensation. Relatively, a support revising algorithm is proposed. The localizer's ball-socket approaches the ball-head based on the displacement sensors. According to the points selected from its spherical surface, the coordinates of ball-head spherical center are computed by geometry. Finally, as a typical application, the device is used to conduct a test-fuselage's ball-head into a localizer's ball-socket. Positional deviations of the spherical centers between the ball-head and the ball-socket in the x, y, and z directions are all controlled within ±0.05 mm under various working conditions. The results of the experiments show that the device has the characteristics of high precision, excellent stability, strong operability, and great potential to be applied widely in the modern aircraft industry.

关键词： Aircraft digital assembly Large aircraft component Accurate support Ball joint Displacement sensor Three coordinate numerical control localizer

论康德的义务观对新时代青年使命感塑成的启示意义

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合肥师范学院学报 2024年第2期42卷 7-12页

作者：陆杰荣姜夏辽宁大学哲学院辽宁沈阳110036

康德的道德哲学主张义务是道德价值的来源,义务的内容来自纯粹实践理性。义务具有三个特点:在动机上具有纯粹性、在内容上具有普遍性、在情感上保持敬畏心。使命是最高的义务,是人价值的最高体现。以康德义务观为借鉴,新时代青年的使命... 详细信息

康德的道德哲学主张义务是道德价值的来源,义务的内容来自纯粹实践理性。义务具有三个特点:在动机上具有纯粹性、在内容上具有普遍性、在情感上保持敬畏心。使命是最高的义务,是人价值的最高体现。以康德义务观为借鉴,新时代青年的使命需要在各种错误思潮中证成自身动机的纯粹性、在全球化语境中证成自身内容的普遍性。康德对道德内在性的强调,为良好的使命动机的培育、使命行动的主体参与感及自律性注入了活力。康德对义务的思考对于开解使命教育的形式化困境具有重要的启示意义。

关键词：康德义务青年使命动机自律

Safety lifetime analysis method for multi-mode time-dependent structural system

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Chinese Journal of Aeronautics 2022年第11期35卷 294-308页

作者： Yingshi HU Zhenzhou LU Ning WEI xia jiang Changcong ZHOU School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China

It is important to determine the safety lifetime of Multi-mode Time-Dependent Structural System(MTDSS). However, there is still a lack of corresponding analysis ***, this paper establishes MTDSS safety lifetime model firstly, and then proposes a Kriging surrogate model based method to estimate safety lifetime. The first step of proposed method is to construct the Kriging model of MTDSS performance function by using extremum learning function. By identifying possible extremum mode of MTDSS, the performance function of MTDSS can be equivalently transformed into the one of Single-mode Time-Dependent Structure(STDS).The second step is to use the Advanced First Failure Instant Learning Function(AFFILF) to train the Kriging model constructed in the first step, so that the convergent Kriging model can identify the possible First Failure Instant(FFI) of STDS. Then safety lifetime can be searched quickly by dichotomy search. By using AFFILF, the minimum instant that the state is not accurately identified by the current Kriging model is selected as the training point, which avoids the unnecessary calculation which may be introduced into the existing First Failure Instant Learning Function(FFILF).In addition, the Candidate Sample Pool(CSP) reduction strategy is also adopted. By adaptively deleting the random candidate sample points whose FFI have been accurately identified by the current Kriging model, the training efficiency is further improved. Three cases show that the proposed method is accurate and efficient.

关键词： Kriging Learning function Lifetime System reliability Time-dependent reliability analysis

Distr ibution, risk and bioavailability of metals in sediments of Lake Yamdrok Basin on the Tibetan Plateau, China

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Journal of Environmental Sciences 2020年第11期32卷 169-179页

作者： Feifei Che Junyi Chen Bo Zhang xia jiang Shuhang Wang National Engineering Laboratory for Lake Pollution Control and Ecological Restoration Chinese Research Academy of Environmental SciencesBeijing l00012China

Total contents of metals in soil and sediments on the Tibetan Plateau of China have been widely analyzed,but existing information is insufficient to effectively evaluate metal ecological risk because of a lack of metal bioavailability *** this study,distribution,potential risk,mobility and bioavailability of metals in sediments of Lake Yamdrok Basin in Tibet of China were explored by combined use of total digestion,sequential extraction and the diffusive gradient in thin-films(DGT).Average concentrations of Cr,Ni,Cu,Zn,As,Cd and Pb in surface sediments were 31.25,30.31,22.00,45.04,31.32,0.13 and 13.39 mg/kg,*** levels of metals were found near the inflowing *** form was dominant in Cr,Ni,Zn,Cd and Pb,and reducible form was dominant in As and *** in surface sediments showed a low enrichment degree overall,but Cd and As had higher ecological risk levels than the other ***,there was a larger average proportion of exchangeable form of As(20.4%)and Cd(9.0%)than the other metals(1.7%-3.3%),implying their higher mobility and release *** DGT-labile concentrations of Cr,Ni,Cu,Zn,As,Cd and Pb were 0.5,4.5,0.7,25.1,60.0,0.22 and 1.0μg/L,*** DGT-labile As was significantly correlated with extractable As forms(p<0.01),suggesting that extractable As in sediments acts as a"mobile pool"for bioavailable *** results suggest potential risks of As and Cd,especially As,deserve further attention in Lake Yamdrok Basin.

关键词： Sequential extraction the Diffusive gradients in thin films(DGT) Mobility Geochemical baseline Tibet

A Fully Distributed Hybrid Control Framework For Non-Differentiable Multi-Agent Optimization

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IEEE/CAA Journal of Automatica Sinica 2022年第10期9卷 1792-1800页

作者： xia jiang xianlin Zeng Jian Sun Jie Chen Yue Wei the Key Laboratory of Intelligent Control and Decision of Complex Systems School of AutomationBeijing Institute of TechnologyBeijing 100081 the Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China IEEE the School of Electronic and Information Engineering Tongji UniversityShanghai 200082 the Peng Cheng Laboratory Shenzhen 518055China

This paper develops a fully distributed hybrid control framework for distributed constrained optimization *** individual cost functions are non-differentiable and *** on hybrid dynamical systems,we present a distributed state-dependent hybrid design to improve the transient performance of distributed primal-dual first-order optimization *** proposed framework consists of a distributed constrained continuous-time mapping in the form of a differential inclusion and a distributed discrete-time mapping triggered by the satisfaction of local jump *** the semistability theory of hybrid dynamical systems,the paper proves that the hybrid control algorithm converges to one optimal solution instead of oscillating among different *** simulations illustrate better transient performance of the proposed hybrid algorithm compared with the results of the existing continuous-time algorithms.

关键词： Distributed algorithm hybrid framework multiagent network non-differentiable optimization