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Position optimization of particular solution sources for distributed source boundary point method by volume velocity-matching

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Chinese Journal of Acoustics 2015年第2期34卷 123-137页

作者： WU Shaowei XIANG Yang LI Shengyang School of Energy and Power Engineering Wuhan University of Technology Key Laboratory of Marine Power Engineering & Technology Ministry of Communications

Choosing particular solution source and its position have great influence on accu- racy of sound field prediction in distributed source boundary point method. An optimization method for determining the position of particular solution sources is proposed to get high accu- racy prediction result. In this method, tripole is chosen as the particular solution. The upper limit frequency of calculation is predicted by setting 1% volume velocity relative error limit using vibration velocity of structure surface. Then, the optimal position of particular solution sources, in which the relative error of volume velocity is minimum, is determined within the range of upper limit frequency by searching algorithm using volume velocity matching. The transfer matrix between pressure and surface volume velocity is constructed in the optimal position. After that, the sound radiation of structure is calculated by the matrix. The results of numerical simulation show that the calculation error is significantly reduced by the proposed method. When there are vibration velocity measurement errors, the calculation errors can be controlled within 5% by the method.

关键词： Position optimization of particular solution sources for distributed source boundary point method by volume velocity-matching

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Leaf metabolomic traits decipher the invasiveness of Alternanthera philoxeroides in urban wetlands

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Science of the Total Environment 2025年 968卷 178888页

作者： Huang, Xiaolong Yang, Jinming Yang, Xue Wang, Tong Meng, Jie Guo, Xiao Wang, Yang Xiong, Wen Zeng, Jin Wu, Zhaoshi Li, Kuanyi Jeppesen, Erik Key Laboratory of Lake and Watershed Science for Water Security Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing211135 China College of Landscape Architecture and Forestry Qingdao Agricultural University Qingdao266109 China Key Laboratory for Green Chemical Process of Ministry of Education Hubei Key Laboratory of Novel Reactor and Green Chemical Technology Institute of Changjiang Water Environment and Ecological Security School of Environmental Ecology and Biological Engineering Wuhan Institute of Technology Wuhan430205 China College of Life Sciences Hubei Normal University Huangshi435002 China Sino-Danish College University of Chinese Academy of Sciences Beijing China Department of Ecoscience Aarhus University Aarhus Denmark Limnology Laboratory Department of Biological Sciences and Centre for Ecosystem Research and Implementation Middle East Technical University Ankara Turkey Institute of Marine Sciences Middle East Technical University Erdemli-Mersin Turkey Institute for Ecological Research and Pollution Control of Plateau Lakes School of Ecology and Environmental Science Yunnan University Kunming China

Urbanisation has been considered to promote exotic plant invasion. Ecophysiology predicts phenotypic variation and potential evolution following urbanisation and can be used to evaluate plant invasiveness. However, few studies have included the role of ecophysiological traits for such invasiveness in urban ecosystems. Traditional plant functional traits have been used but have their limitations. Novel approaches such as metabolomics may potentially be useful. The present study explored the invasiveness of the cosmopolitan noxious invasive plant Alternanthera philoxeroides in urban and periurban areas of a megacity city in China using both traditional leaf functional traits and novel leaf metabolome as indicators. We found that traditional leaf functional traits, including specific leaf area, nitrogen concentration, carbon:nitrogen ratio and construction costs, did not differ between urban and periurban A. philoxeroides populations. However, metabolomic profiling showed that the urban populations had an up-regulated expression of zeatin and purine, two cytokinins correlated with plant growth and a down-regulated expression of isoflavonoids, a defensive metabolite for herbivory. Leaf metabolome may, therefore, be sensitive in deciphering the facilitative effects of urbanisation on plant invasion. We also found that the urban populations of A. philoxeroides accumulated more beneficial microbes, which might enhance their invasiveness. Urbanisation likely promotes exotic plants invasion through generation of metabolites, which stimulates growth via modification of the soil microbiome. Our results indicate that leaf metabolome may be used for interpreting plant invasiveness and predicting plant invasion. © 2025 Elsevier B.V.

关键词： Plant diseases

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Application of OPC technology in supervisory system of marine electrical propulsion

Application of OPC technology in supervisory system of marin...

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Pacific-Asia Conference on Circuits, communications and System

作者： Zhu, Jin Zhang, Xiumei Kang, Wei Key Lab of Marine Technology and Control Engineering Ministry of Communications PRC Shanghai Maritime University Shanghai 201306 China

ISBN: (纸本)9781457708565

In this paper, an intensive research was made into the OPC technology and the OPC Data access specification, then the application of OPC communications in the supervisory system of marine electrical propulsion was proposed to achieve data exchange between the field control station and operator station. The OPC Server was used to collect the state and key parameters of the control system, and the OPC client communication program was realized in the Delphi7.0 IDE, thus completing the supervisory and management of entire marine electrical propulsion system. Experimental results showed that the client has improved considerably in timeliness and satisfied the requirements of ship electric propulsion supervisory system which was more flexible and extensible. © 2011 IEEE.

关键词： Electronic data interchange

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marine AC high-capacity drive experiment system

Marine AC high-capacity drive experiment system

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2010 International Conference on Computer, Mechatronics, control and Electronic engineering, CMCE 2010

作者： Shen, Aidi Huang, Hui Kang, Wei Key Lab. Marine Technology and Control Engineering Ministry Communications Shanghai Maritime University Shanghai 201306 China

ISBN: (纸本)9781424479566

With ac drive system holding dominant status in marine application field, an energy-fed high-capacity AC drive experimental system was proposed for testing different ac drive systems and offsetting the shortcomings of home and abroad drive systems. The system is made up of load subsystem and tested drive subsystem, which resolved the replacement of tested drive subsystem. The load subsystem applies torque control and implements steady and dynamic performance test. Experimental data indicate that the system fulfils the testing requirement of the marine ac drive system. © 2010 IEEE.

关键词： Electric drives

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Layer by Layer Assembly of Poly(Allylamine Hydrochloride)/Phosphate Ions and Poly(Sodium 4-Styrene Sulfonate) Membrane for Forward Osmosis Application

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Journal of Ocean University of China 2019年第3期18卷 743-749页

作者： ZHOU Wen YU Li LI Yiming GAO Baoyu WANG Zhining Key Laboratory of Marine Chemistry Theory and Technology Ministry of Education Ocean University of China Qingdao 266100 China Shandong Key Laboratory of Water Pollution Control and Resource Reuse School of Environmental Science and Engineering Shandong University Jinan 250100 China

Based on the layer by layer(Lb L)assembly technology,the nano-scale composite membrane with excellent structure can be prepared by changing the polyelectrolyte and controlling the deposition *** and phosphate ions(Pi)can be self-organized to form supramolecular systems which could be exploited to stabilize the interfacial *** LbL membrane was made of the positively charged poly(allylamine hydrochloride)(PAH)self-organized with Pi and the negatively charged poly(sodium 4-styrene sulfonate)(PSS)alternatively on top of a poly(acrylonitrile)(PAN)*** to the membrane without Pi,the membrane assembled by PAH/Pi improved forward of flux and reduced flux of *** concentration of PAH and PSS,deposition time,pH and number of layers showed significant influences on the performance of the *** this experiment,we systematically investigated the preparation conditions and under the optimized conditions the prepared membrane exhibited high water fluxes of 13.5 L m^-2 h^-1 with corresponding salt to water flux,Js/Jv,ratio of 0.07 g L^-1 tested by forward osmosis when DI water as feed solution and 2 mol L^-1 MgCl2 as draw solution.

关键词： forward osmosis layer by layer(LbL) polyelectrolyte phosphate ions

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A TIME-SLIDING WINDOW FOR CNN BEARING FAULT DIAGNOSIS 28

A TIME-SLIDING WINDOW FOR CNN BEARING FAULT DIAGNOSIS

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28th International Congress on Sound and Vibration, ICSV 2022

作者： Miao, Jiang Yang, Xiang School of Marine and Energy Power Engineering Wuhan University of Technology Wuhan China Key Laboratory of Marine Power Engineering and Technology Ministry of Communications Wuhan430063 China

ISBN: (纸本)9789811850707

As a critical component of rotating machines, bearing failures can decrease the efficiency of machinery or even bring it to an emergency stop. To enhance the operational efficiency of rotating machinery and prevent unplanned machine shutdown, a time-window sliding convolutional neural network of fault diagnosis of bearing is proposed in this paper. Firstly, to increase the fault feature information, the time window sliding is applied to the original fault signal, while the short-time Fourier transform is applied to the window signal to obtain a time-frequency map of the fault signal. Then, a deep Convolutional neural network fault diagnosis model is constructed, which contains five convolutional layers for deep feature mining, three fully connected layers for fault pinpointing, and a random deactivation (dropout layer) is introduced to the network structure to prevent overfitting. Finally, the time-frequency map is input into the fault diagnosis model to accomplish bearing fault diagnosis. To validate the diagnosis accuracy of the method, the failure data on the drive end model 6205-2RS JEM SKF deep groove ball bearing in the CWRU public data set was used. The results show that this method can improve fault identification accuracy in contrast to conventional CNN networks. © International Institute of Acoustics and Vibration (IIAV), 2022.

关键词： Failure analysis

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Charge and separation characteristics of nanofiltration membrane embracing dissociated functional groups

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Frontiers of Environmental Science & engineering 2014年第5期8卷 650-658页

作者： Zhun MA Meng WANG Xueli GAO Congjie GAO Key Laboratory of Marine Chemistry Theory and Technology Ministry of Education College of Chemistry and Chemical Engineering Ocean University of China Qingdao 266100 China Environmental Simulation and Pollution Control State Key Joint Laboratory School of Environment Tsinghua University Beijing 100084 China

The current work focused on the investigation of charge and separation characteristics of nanofiltration （NF） membrane embracing dissociated functional groups under different electrolyte solutions. The electro-kinetic method was carried out to assess the membrane volume charge density （X） with different salt concentrations ranging from 0.1 to 10 mol. m-3 and different electrolyte species, such as type 1-1, type 2-1 and type 3-1. The Donnan steric pore model-dielectric exclusion （DSPM- DE） model was employed to evaluate the separation characteristics of the NF membrane for wide range of electrolyte concentration （from 25.7 to 598.9mol·m^-3）. The results indicated that the dissociation of the hydro- philic functional groups and the specific adsorption contributed to charge formation on membrane surface. The former played a dominant role in type 1-1 and type 2-1 electrolytes at dilute aqueous solutions （0.1-0.5 mol · m^3）. However, for type 3-1 electrolyte, specific adsorp- tion should contribute to the charge effect to a large extent. Moreover, the correlation between the volume charge density and feed concentration was in accordance with Freundlich isotherm. Furthermore, it was found that the separation characteristic of NF membrane could be evaluated well by DSPM-DE model coupling with electro-kinetic method in a whole concentration range.

关键词： Sulfonated polyethersulfone nanofiltrationmembrane charge characteristics electro-kinetic method,volume charge density separation behavior

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Electronic-property dependent interactions between tetracycline and graphene nanomaterials in aqueous solution

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Journal of Environmental Sciences 2018年第4期30卷 286-294页

作者： Lin He Fei-fei Liu Mengyao Zhao Zhen Qi Xuefei Sun Muhammad Zaheer Afzal Xiaomin Sun Yanhui Li Jingcheng Hao Shuguang Wang Shandong Key Laboratory of Water Pollution Control and Resource Reuse School of Environmental Science and EngineeringShandong University Insistute of Marine Science and Technology Shandong University Environment Research Institute Shandong University Laboratory of Fiber Materials and Modern Textile The Growing Base for State Key Laboratory Qingdao University Key Laboratory of Colloid and Interface Chemistry Ministry of Education Shandong University

Understanding the interactions between graphene nanomaterials（GNMs） and antibiotics in aqueous solution is critical to both the engineering applications of GNMs and the assessment of their potential impact on the fate and transport of antibiotics in the aquatic environment. In this study, adsorption of one common antibiotic, tetracycline, by graphene oxide（GO） and reduced graphene oxide（RGO） was examined with multi-walled carbon nanotubes（MWCNTs） and graphite as comparison. The results showed that the tetracycline adsorption capacity by the four selected carbonaceous materials on the unit mass basis followed an order of GO ＆gt; RGO ＆gt; MWCNTs ＆gt; graphite. Upon normalization by surface area,graphite, RGO and MWCNTs had almost the same high tetracycline adsorption affinity while GO exhibited the lowest. We proposed π-electron-property dependent interaction mechanisms to explain the observed different adsorption behaviors. Density functional theory（DFT） calculations suggested that the oxygen-containing functional groups on GO surface reduced its π-electron-donating ability, and thus decreased the π-based interactions between tetracycline and GO surface. Comparison of adsorption efficiency at different p H indicated that electrostatic interaction also played an important role in tetracycline-GO interactions. Site energy analysis confirmed a highly heterogeneous distribution of the binding sites and strong tetracycline binding affinity of GO surface.

关键词： Graphene oxide Reduced graphene oxide Tetracycline Adsorption DFT calculation π-Based interaction

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Experimental research on the responses of ship shaft under loadings on bearings 24

Experimental research on the responses of ship shaft under l...

引用

24th International Congress on Sound and Vibration, ICSV 2017

作者： Zhang, Cong Qin, Li School of Energy and Power Engineering Key Laboratory of Marine Power Engineering and Technology Ministry of Communications National Engineering Research Center for Water Transport Safety Wuhan University of Technology Wuhan430063 China Key Laboratory of Metallurgical Equipment and Control Technology Ministry of Education Hubei Key Laboratory of Mechanical Transmission and Manufacturing Engineering Wuhan University of Science and Technology Wuhan430081 China

With the development of the large-scale ships, the power and size parameters of ship shaft are increasing apparently. As a result, the problems caused by the coupling effects between hull and shaft via bearing structure are prominent. Based on the characteristics of dynamic excitations for the ship shaft, a reasonable experiment plan is designed. In this experiment, transversal, vertical, longitudinal loads are considered on the intermediate bearing and the stern bearing to simulate hull excitations on the bearings. Different rotational speed is also considered. The characteristics of transversal, longitudinal and rotational vibration of propulsion shaft are studied. The coupling effects are discussed.

关键词： Hulls (ship)

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Coordinated Planning Transmission Tasks in Heterogeneous Space Networks:A Semi-Distributed Approach

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China communications 2023年第1期20卷 261-276页

作者： Runzi Liu Weihua Wu Zhongyuan Zhao Xu Ding Di Zhou Yan Zhang School of Information and Control Engineering Xi’an University of Architecture and TechnologyXi’an 710055ShaanxiChina State Key Laboratory of ISN School of Telecommunications EngineeringXidian UniversityXi’an 710071ShaanxiChina Key Laboratory of Universal Wireless Communications(Ministry of Education) Beijing University of Posts and TelecommunicationsBeijing 100876China

This paper studies the coordinated planning of transmission tasks in the heterogeneous space networks to enable efficient sharing of ground stations cross satellite ***,we first formulate the coordinated planning problem into a mixed integer liner programming(MILP)problem based on time expanded ***,the problem is transferred and reformulated into a consensus optimization framework which can be solved by satellite systems *** alternating direction method of multipliers(ADMM),a semi-distributed coordinated transmission task planning algorithm is proposed,in which each satellite system plans its own tasks based on local information and limited communication with the coordination *** results demonstrate that compared with the centralized and fully-distributed methods,the proposed semi-distributed coordinated method can strike a better balance among task complete rate,complexity,and the amount of information required to be exchanged.

关键词： heterogeneous space network transmission task task planning coordinated scheduling

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