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Chinese Journal of Electronics 2024年第2期33卷 463-471页

作者： Qiang sun Yongling BAN jun HU School of Electronic Science and Engineering University of Electronic Science and Technology of China

Exploring the multifunctional array antenna suitable for complex communication environment has very important research value. In this paper, a millimeter wave(mm-wave) double longitudinal sawtooth slot array antenna(DLSA) based on substrate integrated waveguide(SIW) technology is proposed, which has wideband, highgain and novel beam characteristics. Two irregular longitudinal slots are etched on the SIW conductor surface as the radiation structure. To improve the bandwidth of the DLSA, the metallized vias are added at the transition point of the slots to construct multiple resonant frequency points. By adjusting the size of the slots and the position of the metallized vias, the phase constant can be regulated, and the unusual beam characteristics can be obtained. That is to say, in the lower frequency band, the beam pointing angle increases with frequency. In the higher frequency band,the beam pointing angle is maintained at a fixed angle. Finally, to improve the antenna gain, a 16 × 8 DLSA is fabricated, measured and discussed. The proposed antenna has an impedance matching bandwidth close to 9.7 *** 27 to 33 GHz, the beam pointing angle changes from 8° to 29°. From 33 to 37 GHz, the beam pointing angle is fixed at 29°, and the pointing angle error range is ±1°. In addition, the measured maximum gain is 22.9 d Bi at32 GHz.

关键词： Antenna measurements Slot antennas Surface waves Resonant frequency Gain measurement Conductors Frequency measurement

Event-Triggered Bipartite Consensus Tracking and Vibration Control of Flexible Timoshenko Manipulators Under Time-Varying Actuator Faults

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1190-1201页

作者： Xiangqian Yao Hao sun Zhijia Zhao yu Liu School of Automation Science and Engineering South China University of TechnologyGuangzhou 510640China Yongjiang Laboratory Ningbo 315202 School of Astronautics Harbin Institute of TechnologyHarbin 150001China School of Mechanical and Electrical Engineering Guangzhou UniversityGuangzhou 510006China

For bipartite angle consensus tracking and vibration suppression of multiple Timoshenko manipulator systems with time-varying actuator faults,parameter and modeling uncertainties,and unknown disturbances,a novel distributed boundary event-triggered control strategy is proposed in this *** contrast to the earlier findings,time-varying consensus tracking and actuator defects are taken into account *** addition,the constructed event-triggered control mechanism can achieve a more flexible design because it is not required to satisfy the input-to-state *** achieve the control objectives,some new integral control variables are given by using back-stepping technique and boundary ***,adaptive neural networks are applied to estimate system *** the proposed event-triggered scheme,control inputs can reduce unnecessary ***,tracking errors and vibration states of the closed-looped network can be exponentially convergent into some small fields,and Zeno behaviors can be *** last,some simulation examples are given to state the effectiveness of the control algorithms.

关键词： Vibration satisfy bipartite

Survey on performance of vertical slot and nature-like fishways at Angu hydropower station, Southwest China

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Water Science and Engineering 2024年第1期17卷 83-91页

作者： jun-jian sun Jia-yue Shi Qi Zhang Xiao-tao Shi jun-jun Tan PowerChina Huadong Engineering Corporation Limited Hangzhou 311122China Hubei International Science and Technology Cooperation Base of Fish Passage China Three Gorges UniversityYichang 443002China

To restore dam-blocked natural fish migratory passages,a growing number of artificial fishways have been built in water conservancy and hydropower projects in *** Angu hydropower station involved diverse important fish habitats in the lower reaches of the Daduhe River in Southwest ***,a vertical slot fishway(VSF)and a nature-like fishway(NLF)were built near the backwater area of the reservoir to connect the upstream and downstream *** and aquatic ecological surveys were conducted after the completion of the project to estimate the fish passing effect of the two *** results indicated that both fishways were in effective operation and could maintain the desired hydrodynamic conditions and be used by several local fish *** the survey,149 fish from 15 species and 111 fish from 17 species were captured by the traps in the VSF and NLF,respectively,while 1263 fish from 27 species were found in the downstream *** species captured in the VSF were not found in the NLF,and vice versa,which implied the different preferences of ***,3789 signals including 2099 upward ones and 1690 downward ones were monitored with an ultrasonic fish detector at the inlet of the *** findings revealed the characteristics of fish species observed in and near the fishways and provided valuable insights into the different fish passing capabilities of VSFandNLF.

关键词： Vertical slot fishway Nature-like fishway Aguatic ecological survey Fishwaymonitoring Statistical analysis

Evolution of copper species during heat treatment and its effect on CO oxidation reaction on CuCeZrO_(y) catalyst synthesized by a facile solvent-free route

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Journal of Rare Earths 2024年第4期42卷 660-667页

作者： Guangying Fu Dongsen Mao jun yu Qiangsheng Guo School of Chemical and Environmental Engineering Shanghai Institute of TechnologyShanghai21418 China The ZeoMat Group Qingdao Institute of Bioenergy and Bioprocess TechnologyCASQingdao26611China

Several ternary oxides CuCeZrO_(y)(CCZ)were synthesized by a facile grinding method followed by calcination at high temperatures,and used as catalysts for CO oxidation at low *** influences of calcination temperature(400-600℃)on the physicochemical properties of the assynthesized ternary oxides were investigated by thermogravimetric analysis/differential scanning calorimetry(TGA/DSC),X-ray diffraction(XRD),transmission electron microscopy(TEM),Raman,inductively coupled plasma-optical emission spectrometry(ICP-OES),N_(2) adsorption,H_(2)-temperature programmed reduction(H_(2)-TPR),and X-ray photoelectron spectroscopy(XPS)*** results show that the increase in calcination temperature from 400 to 500℃is conducive to the high dispersion of CuOx on catalyst surface and the incorporation of Cu species into the support to form the Cu-Ce-Zr-O solid *** raising of calcination temperature from 500 to 600℃,however,leads to the segregation of Cu species from the solid solution to aggregate on support surface and growth of highly dispersed CuOx *** highest catalytic activity is acquired over the CCZ calcined at 500℃,which can be ascribed to the largest contents of Cu+species and oxygen vacancies owing to the formation of the maximum amount of Cu-Ce-Zr-O solid solution.

关键词： CuCeZrO_(y)catalyst co oxidation Calcination temperature Grinding method Oxalate precursor Rare earths

Progress on the glassy-crystal laminates:From design,microstructure to deformation and future solutions

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Journal of Materials Science & Technology 2024年第5期172卷 113-144页

作者： yu Chen Ronggao Cui jun Shen Gang Wang College of Mechatronics and Control Engineering Shenzhen UniversityShenzhen 518060China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China Department of Motor Design Business Weichai New Energy Technology Co.Ltd.Weifang 261061China Guangdong Key Laboratory of Electromagnetic Control and Intelligent Robots Shenzhen UniversityShenzhen 518060China Laboratory for Microstructures Institute of MaterialsShanghai UniversityShanghai 200444China

The development of new design strategies to create innovative structural materials,refine existing ones,and achieves compatible combinations of strength and plasticity remains a worldwide *** alloys,such as shape memory alloys(SMAs),bulk metallic glasses(BMGs),high entropy alloys(HEAs),and heterogeneous pure metals such as Cu,have excellent mechanical responses,but they still fall short of meeting all the requirements of structural materials due to specific flaws,such as lack of tensile de-formation for BMGs and low yielding strength for *** address these shortcomings,proposals such as integrating glassy matrices and crystallized alloys,such as HEAs/SMAs,have been ***,these solutions have unresolved issues,such as the challenging control of B2 phase formation in BMG ***,glass-crystal(A/C)laminated alloys with alternating layers have been reported to exhibit improved mechanical properties and activated work-hardening behaviors,but they still face press-ing issues such as bonding interfaces and unknown deformation *** review focuses on design routes such as the selection of alloy components and processing techniques,exploration of micro-structural evolution and deformation modes with an increase in strain,and future solutions to address pressing and unsolved *** prominent advantages include diversified deformation mechanisms,such as deformation twinning,martensitic phase transformation,and precipitation hardening,as well as tuned interactive reactions of shear bands(SBs)near the A/C ***,this review provides a promising pathway to design and develop structural materials in the materials field community.

关键词： Glassy-crystal laminates Bulk metallic glasses High entropy alloys Shape memory alloys Microstructure Deformation mechanisms Future solutions

Investigation on the influence of vortex generator on particle resuspension

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Particuology 2024年第3期86卷 126-136页

作者： Dongchi yu jun-Li Lin Jin-Han Xie ASML 80W Tasman DrSan Jose95134CaliforniaUSA Department of Mechanics and Engineering Science at College of Engineering and State Key Laboratory for Turbulence and Complex Systems Peking UniversityBeijing100081China

The vortex generator(VG)and its well-known effect in flow optimization are widely studied and employed across different engineering ***,while the same working principles of VG may be well suited for the applications on surface-cleaning technologies,such promising potential is hardly,if any,explored in the published ***,in the present study,the influence on flow-induced particle resuspension brought by a rectangular vG in a channel flow is investigated with the help of highfidelity computational fluid dynamics *** increases of particle removal forces and resuspension rates are discovered in long,strip-like regions with reduced boundary-layer thickness resulted from the vG-induced vortices,and the enhancement effect is especially significant for configurations with the VG installed at a greater angle of *** is also shown that while the resuspension enhancements on the lower and the upper surfaces of the channel exhibit distinct statistical characteristics,having a VG in the channel improves the overall particle-removing capability of the channel flow by introducing higher surface-averaged removal forces and particle resuspension *** but not least,the increase of resuspension rate is especially significant for the smaller,micron-scale particles which are otherwise hardly disturbed by a VG-less channel flow,and such resuspension-enhancement effectgenerally subsides with increasing particle size.

关键词： Particle resuspension Vortexgenerator CFD Surface cleaning

Effect of nourishing Yin and purging fire Chinese herbal mixture on delaying light-induced premature puberty in rats

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Journal of Traditional Chinese Medicine 2024年第1期44卷 95-102页

作者： sun Yanyan XUE yuanyuan sun Wen WANG Yonghong yu Jian Department of Traditional Chinese Medicine Children's Hospital of Fudan UniversityShanghai 201102China Department of Pediatrics Zibo Central HospitalZibo 255000China

OBJECTIVE:To elucidate the mechanism of the nourishing Yin and purging fire Chinese herbal mixture(NYPF)in delaying light-induced premature puberty in ***:Twenty-one days old female SpragueDawley rats were randomly assigned to normal group(N),long light exposure group(L),NYPF and normal saline group(NS).Rats in the L,NYPF and NS groups were exposed to 16 h:350 lux light/8 h:dark,while rats in the N group were exposed to 12 h:50 lux light/12 h:*** and normal saline was administered to the rats in the NYPF group or NS group,respectively,from day *** rats in every group were sacrificed at 9 *** day 28(P28),on the day when rat's vulva opened in the L group(L-VO),on the day when the first estrous interphase occurred in rats of L group(L-E1),and on the day when the second estrous interphase occurred in rats of L group(L-E2),***:On day 34,all rats in the L group,80%of rats in the NS group,40%of rats in the N group,and 20%of rats in the NYPF group showed complete opening of the *** P28,m RNA level of hypothalamic kisspeptin(Kiss-1)in the L group was significantly higher than that in the N group(P<0.05).The rats in the L and NS groups had significantly lower hypothalamic argininephenylalanine-amide(RFamide)-related peptide 3(RFRP-3)m RNA levels than those in the N group(P<0.05),whereas RFRP-3 m RNA level was significantly higher in the NYPF group than that in the L group(P<0.05).At L-VO,the ovarian index of the L and NS groups was significantly higher than that of the N group(P<0.05)and estradiol(E2)level of the NYPF group was significantly lower than that of the N and NS groups(P<0.05);hypothalamic Kiss-1 m RNA level in the L and NS groups was significantly higher than that in the N and NYPF groups(P<0.05),whereas hypothalamic RFRP-3 m RNA level in the L,NYPF,and NS groups was significantly lower than that in the N group(P<0.05).At L-E1,E2 level of the L and NS groups was significantly higher than that of the N group(P<0.01),wher

关键词： light puberty precocious kisspeptins RFRP-3 melatonin Nourishing Yin and Purging Fire

A Deep Model for Partial Multi-label Image Classification with Curriculum-based Disambiguation

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Machine Intelligence Research 2024年第4期21卷 801-814页

作者： Feng sun Ming-Kun Xie Sheng-jun Huang MIIT Key Laboratory of Pattern Analysis and Machine Intelligence College of Computer Science and TechnologyNanjing University of AeronauticsandAstronauticsNanjing211106China

In this paper,we study the partial multi-label(PML)image classification problem,where each image is annotated with a candidate label set consisting of multiple relevant labels and other noisy *** PML methods typically design a disambiguation strategy to filter out noisy labels by utilizing prior knowledge with extra assumptions,which unfortunately is unavailable in many real ***,because the objective function for disambiguation is usually elaborately designed on the whole training set,it can hardly be optimized in a deep model with stochastic gradient descent(SGD)on *** this paper,for the first time,we propose a deep model for PML to enhance the representation and discrimination *** the one hand,we propose a novel curriculum-based disambiguation strategy to progressively identify ground-truth labels by incorporating the varied difficulties of different *** the other hand,consistency regularization is introduced for model training to balance fitting identified easy labels and exploiting potential relevant *** experimental results on the commonly used benchmark datasets show that the proposed method significantlyoutperforms the SOTA methods.

关键词： Partial multi-label image classification curriculum-based disambiguation consistency regularization label difficulty candidatelabel set.

Engineering phonon thermal transport in few-layer PdSe_(2)

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Frontiers of physics 2024年第3期19卷 135-141页

作者： Meilin Li Huanhuan sun jun Zhou yunshan Zhao Phonon Engineering Research Center of Jiangsu Province Center for Quantum Transport and Thermal Energy ScienceInstitute of Physics Frontiers and Interdisciplinary SciencesSchool of Physics and TechnologyNanjing Normal UniversityNanjing 210023China

Engineering phonon transport in low-dimensional materials has great significance not only for fundamental research,but also for thermal management applications of electric ***,due to the difficulties of micro and nano processing and characterization techniques,the work on tuning phonon transport at nanoscale are *** this work,by introducing Ar+plasma,we probed the phonon transport in two-dimensional(2D)layered semiconductor PdSe_(2)under different defect *** using thermal bridge method,the thermal conductivity was measured to decrease by 50%after a certain Ar+irradiation,which implied a possible phase ***,Raman characterizations were performed to show that the Raman sensitive peaks of PdSe_(2)was red-shifted and finally became disappeared with the increase of defect concentration.“Defect engineering”proves be a practical strategy in tuning the phonon thermal transport in low-dimensional materials,thus providing guidance for potential application in designing thermoelectric devices with various emerging materials.

关键词： phonon transport PdSe_(2) defects thermal bridge method

Risk assessment of oil and gas investment environment in countries along the Belt and Road Initiative

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Petroleum Science 2024年第2期21卷 1429-1443页

作者： Bao-jun Tang Chang-Jing Ji yu-Xian Zheng Kang-Ning Liu Yi-Fei Ma jun-yu Chen Center for Energy and Environmental Policy Research Beijing Institute of TechnologyBeijing100081China School of Management and Economics Beijing Institute of TechnologyBeijing100081China Collaborative Innovation Center of Electric Vehicles in Beijing BeijingChina Sustainable Development Research Institute for Economy and Society of Beijing BeijingChina Institute of Carbon Neutrality ShanghaiTech UniversityShanghai201210China

With the implementation of the Belt and Road Initiative, China is deepening its cooperation in oil and gas resources with countries along the Initiative. In order to better mitigate risks and enhance the safety of investments, it is of significant importance to research the oil and gas investment environment in these countries for China's overseas investment macro-layout. This paper proposes an indicator system including 27 indicators from 6 dimensions. On this basis, game theory models combined with global entropy method and analytic hierarchy process are applied to determine the combined weights, and the TOPSIS-GRA model is utilized to assess the risks of oil and gas investment in 76 countries along the Initiative from 2014 to 2021. Finally, the GM(1,1) model is employed to predict risk values for 2022-2025. In conclusion, oil and gas resources and political factors have the greatest impact on investment environment risk, and 12 countries with greater investment potential are selected through cluster analysis in conjunction with the predicted results. The research findings may provide scientific decisionmaking recommendations for the Chinese government and oil enterprises to strengthen oil and gas investment cooperation with countries along the Belt and Road Initiative.

关键词： Belt and Road Initiative Oil and Gas Investment Risk assessment