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Mode Conversion and Diffraction of Guided Optical Waves from Magnetostatic Waves under Inclined Bias Magnetic Field

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Communications in Theoretical Physics 2001年第10期36卷 497-502页

作者： wu Bao-Jian liu Gong-Qiang ZOU Zhi-Qiang Department of Applied Physics Shanghai Jiao Tong University Shanghai 200030 China Department of Applied Physics Shanghai Jiao Tong University Shanghai 200030 China Department of Applied Physics Shanghai Jiao Tong University Shanghai 200030 China

The noncollinear interaction of guided optical waves with magnetostatic waves under inclined bias magnetic field is theoretically studied in detail. Similar approach can also be applied to the collinear interaction. Calculation results indicate that the diffraction efficiency (DE) in magnitude is equal to the mode-conversion efficiency (MCE) under vertical bias magnetic field, but they differ greatly under inclined bias magnetic field. By comparison to the case of vertical magnetization, the DE or the MCE can be greatly increased under inclined magnetic field. The characteristic of the DE curves obtained is basically in agreement with the experimental result.

关键词： guided optical wave, magnetostatic wave, mode conversion, diffraction efficiency

Research of air-cushion isolation effects on high arch dam reservoir

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Acta Mechanica Sinica 2011年第5期27卷 675-686页

作者： Shao-Jie Zhang Jiang Chen Yuan-Ze Zhang Hao-wu liu College of Hydraulic ＆ Hydroelectric Engineering Sichuan University610065 Chengdu China Scientific Research Institute of Kunming Investigationand Design Institute China Hydropower Engineering Consultation Group Company650033 Kunming China Institute of Mountain Harzards and Environment Chinese Academy of Sciences610041 Chengdu China

A three-dimensional （3D） finite element model of air-cushion isolated arch dam is presented with the nonlinear gas-liquid-solid multi-field dynamic coupling effect taken into *** this model,the displacement formulation in Lagrange method,pressure formulation in Euler method,nonlinear contact model based on Coulomb friction law are applied to the air-cushion,reservoir and contraction joint domain,*** dynamic response of Jinping I arch dam with a height of 305 m is analyzed using the seismic records of the Wenchuan Earthquake in *** results show that the air-cushion isolation reduces significantly the hydrodynamic pressure as well as the opening width for the contraction joints of high arch dam.

关键词： Air-cushion · Gas-liquid-solid multi-field coupling · Contraction (transverse) joint · Hydrodynamic pressure · Wenchuan Earthquake

Unmanned Ship Identification Based on Improved YOLOv8s Algorithm

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Computers, Materials & Continua 2024年第3期78卷 3071-3088页

作者： Chun-Ming wu Jin Lei wu-Kai liu Mei-Ling Ren Ling-Li Ran Key Laboratory of Modern Power System Simulation and Control&Renewable Energy Technology School of Electrical EngineeringNortheast Electric Power UniversityJilin132012China School of Biomedical Engineering Taiyuan University of TechnologyTaiyuan030600China

Aiming at defects such as low contrast in infrared ship images,uneven distribution of ship size,and lack of texture details,which will lead to unmanned ship leakage misdetection and slow detection,this paper proposes an infrared ship detection model based on the improved YOLOv8 algorithm(R_YOLO).The algorithm incorporates the Efficient Multi-Scale Attention mechanism(EMA),the efficient Reparameterized Generalized-feature extraction module(CSPStage),the small target detection header,the Repulsion Loss function,and the context aggregation block(CABlock),which are designed to improve the model’s ability to detect targets at multiple scales and the speed of model *** algorithm is validated in detail on two vessel *** comprehensive experimental results demonstrate that,in the infrared dataset,the YOLOv8s algorithm exhibits improvements in various performance ***,compared to the baseline algorithm,there is a 3.1%increase in mean average precision at a threshold of 0.5(mAP(0.5)),a 5.4%increase in recall rate,and a 2.2%increase in mAP(0.5:0.95).Simultaneously,while less than 5 times parameters,the mAP(0.5)and frames per second(FPS)exhibit an increase of 1.7%and more than 3 times,respectively,compared to the CAA_YOLO ***,the evaluation indexes on the visible light data set have shown an average improvement of 4.5%.

关键词： Unmanned ships R_YOLO EMA CSPStage YOLOv8s

Pulsed electrolysis of carbon dioxide by large-scale solid oxide electrolytic cells for intermittent renewable energy storage

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Carbon Energy 2023年第4期5卷 2-12页

作者： Anqi wu Chaolei Li Beibei Han wu liu Yang Zhang Svenja Hanson Wanbing Guan Subhash C.Singhal Key Laboratory of Advanced Fuel Cells and Electrolyzers Technology of Zhejiang Province Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingboZhejiangChina Faculty of Science and Engineering University of Nottingham Ningbo ChinaNingboZhejiangChina

CO_(2) electrolysis with solid oxide electrolytic cells(SOECs)using intermittently available renewable energy has potential applications for carbon neutrality and energy *** this study,a pulsed current strategy is used to replicate intermittent energy availability,and the stability and conversion rate of the cyclic operation by a large-scale flat-tube SOEC are *** hundred cycles under pulsed current ranging from -100 to -300 mA/cm^(2) with a total operating time of about 800 h were carried *** results show that after 100 cycles,the cell voltage attenuates by 0.041%/cycle in the high current stage of−300 mA/cm^(2),indicating that the lifetime of the cell can reach up to about 500 *** total CO_(2) conversion rate reached 52%,which is close to the theoretical value of 54.3% at -300 mA/cm^(2),and the calculated efficiency approached 98.2%,assuming heat *** study illustrates the significant advantages of SOEC in efficient electrochemical energy conversion,carbon emission mitigation,and seasonal energy storage.

关键词： carbon dioxide cyclic electrolysis pulse current solid oxide electrolytic cells

Design and Implementation of a Network Management System Based on Mobile RMON Agent

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Journal of China University of Mining and Technology 2006年第3期16卷 325-329页

作者： SHAN Xin liu Peng wu Lin liu Ying GUO Jun School of Information Engineering Beijing University of Posts ＆ Telecommunications Beijing 100876 China

To improve the scalability of RMON-based network management, the concept of Mobile RMON Agent (MRA) was presented by combining the mobile agent technology with RMON. Then an MRA-based Network Management System (MRANMS) was designed and implemented. RMON functions were achieved by programming the mobile agent to make it capture and analyze packets locally. The experimental result on the Grasshopper platform indicates that MRA as a mobile agent can migrate to another subnet and calculate a RMON MIB value and TrafficMatrix in a subnet with 29 hosts. Furthermore, the behavior of MRA can be customized to achieve new RMON functions, such as the statistics of hostTable in RMON MIB. It can be concluded that MRANMS is based on the mode of distribution, and besides the compatibility with standard RMON, the system possesses scalability of management function.

关键词： network management RMON mobile agent MRA scalability

A skew–normal mixture of joint location, scale and skewness models

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Applied Mathematics(A Journal of Chinese Universities) 2016年第3期31卷 283-295页

作者： LI Hui-qiong wu liu-cang YI Jie-yi Department of statistics Yunnan University Faculty of Science Kunming University of Science and Technology School of Mathematical Sciences Beijing Normal University

Normal mixture regression models are one of the most important statistical data analysis tools in a heterogeneous population. When the data set under consideration involves asymmetric outcomes, in the last two decades, the skew normal distribution has been shown beneficial in dealing with asymmetric data in various theoretic and applied problems. In this paper, we propose and study a novel class of models： a skew-normal mixture of joint location, scale and skewness models to analyze the heteroscedastic skew-normal data coming from a heterogeneous population. The issues of maximum likelihood estimation are addressed. In particular, an Expectation-Maximization （EM） algorithm for estimating the model parameters is developed. Properties of the estimators of the regression coefficients are evaluated through Monte Carlo experiments. Results from the analysis of a real data set from the Body Mass Index （BMI） data are presented.

关键词： mixture regression models mixture of joint location scale and skewness models EM algorithm maximum likelihood estimation skew-normal mixtures

Craniofacial morphological microevolution of Holocene populations in northern China

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Chinese Science Bulletin 2007年第12期52卷 1661-1668页

作者： wu XiuJie liu wu ZHANG QuanChao ZHU Hong Christopher J. NORTON Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China Research Center for Chinese Frontier Archaeology Jilin University Changchun 130012 China Laboratory of Quatemary Paleontology Northern Arizona University Flagstaff AZ 86011-4099 USA

In order to better understand microevolutionary processes in Holocene Chinese craniofacial mor- phology, an analysis has been done on 21 metric traits on Neolithic (n=161), Bronze Age (n=423) and modern (n=134) adult male skulls from northern China. The results indicate that the physical characters of these Chinese populations evolved throughout the Holocene. From the Neolithic to Bronze Age to present day, general trends include: cranial and facial sizes decrease; the nose gets narrower and longer; the orbits become narrower and higher; the head is more globular. The expression of the cranial features varies between the different time periods. The decrease in cranial size primarily occurred from the Bronze Age to present day. However, the decrease in facial size, the narrowing of the nose, and the elevation of the orbits took place throughout the Holocene. These traits are likely still evolving. This evolving pattern of the cranial features for the Holocene Chinese populations is similar to that found elsewhere in the world. The decrease in overall craniofacial size is associated with changes in climate and diet. In addition, it is possible that the craniofacial morphological microevolution is controlled by human evolutionary mechanisms.

关键词：全新世中国人人类微进化颅面形态

Vortex chains induced by anisotropic spin-orbit coupling and magnetic field in spin-2 Bose-Einstein condensates

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Chinese Physics B 2022年第6期31卷 204-210页

作者： Hao Zhu Shou-Gen Yin wu-Ming liu Key Laboratory of Display Materials and Photoelectric Devices(Ministry of Education) Tianjin Key Laboratory for Photoelectric Materials and DevicesSchool of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100190China Songshan Lake Materials Laboratory Dongguan 523808China

We investigate the anisotropic spin-orbit coupled spin-2 Bose-Einstein condensates with Ioffe-Pritchard magnetic *** nonzero magnetic field,anisotropic spin-orbit coupling will introduce several vortices and further generate a vortex *** the vortex chain,the vortices connect to each other,forming a line along the *** physical nature of the vortex chain can be explained by the particle current and the momentum *** vortex number inside the vortex chain can be influenced via varying the magnetic *** adjusting the anisotropy of the spin-orbit coupling,the direction of the vortex chain is changed,and the vortex lattice can be ***,accompanied by the variation of the atomic interactions,the density and the momentum distribution of the vortex chain are *** realization and the detection of the vortex chain are compatible with current experimental techniques.

关键词： vortex chain anisotropic spin-orbit coupling magnetic field Bose-Einstein condensates

Characterization of predominant bacteria isolates from clean rooms in a pharmaceutical production unit

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第9期8卷 666-672页

作者： wu Gen-fu liu Xiao-hua Institute of Microbiology School of Life Sciences Zhejiang Universiity Hangzhou 310058 China

Aims: To screen for the predominant bacteria strains distributed in clean rooms and to analyze their phylogenetic relationships. Methods and Results: The bacteria distributed in air, surfaces and personnel in clean rooms were routinely moni-tored using agar plates. Five isolates frequently isolated from the clean rooms of an aseptic pharmaceutical production workshop were selected based on their colony and cell morphology characteristics. Their physiological and biochemical properties, as well as partial 16S rDNA sequences, were analyzed. Results showed that all the five isolates belong to Gram positive bacteria, of which three were Staphylococcus, one Microbacterium and one Bacillus species. Sensitivity tests for these bacteria isolates to 3 disin-fectants showed that isolate F03 was obtuse, and had low susceptivity to UV irradiation, while isolates F02, F01 and F04 were not sensitive to phenol treatment. Isolates F04, F01 and F05 were resistant to chlorhexidine gluconate. Conclusion: Bacteria widely distributed in clean rooms are mainly a group of Gram positive strains, showing high resistance to selected disinfectants. Sig-nificance and impact of the study: Clean rooms are essential in aseptic pharmaceutical and food production. Screening bacteria isolates and identifying them is part of good manufacturing practices, and will aid in finding a more effective disinfection method.

关键词： Clean room Bacteria 16S rDNA Phylogenetic tree Disinfectant Resistant abilities