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Energy Harvesting based on Magnetic Dispersion for Three-Phase Power System

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Energy and Power Engineering 2013年第3期5卷 20-23页

作者： Tarcisio Oliveira de Moraes Júnior Yuri Percy Molina Rodriguez Ewerton Cleudson de Sousa Melo Maraiza Prescila dos Santos Cleonilson Protásio de Souza Federal Institute of Paraíba-IFPB CajazeirasBrazil Department of Electrical Engineering Federal University of Paraíba-UFPBJoao PessoaBrazil

This paper presents a comparative study on Magnetic-Dispersion based Energy Harvesting Systems (MD-EHS) on electrical conductors that supply power for a three-phase AC motor. It introduces two MD-EHS which are based on magnetic cores of different material, named, nanocrystalline, ferrite and iron powder. The first one consists of harvesting energy from magnetic flux through three symmetrical magnetic cores installed on each power conductors of a three-phase AC motor. The second one consists of a single magnetic core for harvesting energy from magnetic flux of only one of these conductors. Both ones have an AC/DC converter and a variable resistor based load. Experimental results have agreed with the theoretical analysis and show that the first proposed MD-EHS is capable of supplying 14 times more energy than the second MD-EHS, considering nanocrystalline cores and phase current of 3 A, and 7.5 times more energy, considering ferrite cores and phase current of 9 A. Such energy can be applied to various low-power devices, especially in wireless sensor network.

关键词： Energy Harvesting Magnetic Dispersion Magnetic Cores

Mechanistic insights into the novel glucose-sensitive behavior of P(NIPAM-co-2-AAPba)

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Science China Chemistry 2020年第3期63卷 377-385页

作者： Qingxian Wang Mian Fu Ying Guan Tony D.James Yongjun Zhang Key Laboratory of Functional Polymer Materials and State Key Laboratory of Medicinal Chemical Biology Institute of Polymer ChemistryCollege of ChemistryNankai UniversityTianjin 300071China Department of Chemistry University of BathClaverton DownBath BA27AYUK

A glucose-sensitive polymer,poly(N-isopropylacrylamide-co-2-acrylamidophenylboronic acid)(P(NIPAM-co-2-AAPba)),was synthesized by reversible addition fragmentation chain transfer(RAFT)*** of glucose results in reduced solubility and hence increased turbidity,rather than the normal increase in solubility(decreased turbidity)observed for other Pba-based glucose-sensitive *** novel glucose-sensitive behavior is explained by a new mechanism,in which glucose acts as an additive and depresses the lower critical solution temperature(LCST)of the polymer,instead of increasing solubility by increasing the degree of ionization of the Pba *** and theoretic analysis for the influence of glucose on the thermal behavior of P(NIPAM-co-2-AAPba)reveals that glucose depresses the LCST of P(NIPAM-co-2-AAPba)copolymers in a two-stage manner,a fast decrease at low glucose concentrations followed by a slow decrease at high glucose *** low glucose concentrations,the binding of glucose with Pba groups on the polymer chain increases the number of glucose molecules proximal to the polymer which influences the thermal behavior of the polymer,causing a rapid decrease in ***,the transition occurs at a glucose concentration equal to the reciprocal of the binding constant between Pba and glucose,thus providing a novel method to determine the binding *** saccharides,including mannose,galactose and fructose,also depress the LCST of P(NIPAM-co-2-AAPba)copolymer in the same way.

关键词： glucose-sensitive mechanism phenylboronic acid thermosensitive binding constant lower critical solution temperature polymers

What and where: A context-based recommendation system for object insertion

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Computational Visual Media 2020年第1期6卷 79-93页

作者： Song-Hai Zhang Zheng-Ping Zhou Bin Liu Xi Dong Peter Hall Tsinghua University Beijing 100084China Beijing National Research Center for Information Science and Technology(BNRist) Tsinghua UniversityBeijing 100084China Department of Computer Science Media Technology Research Center University of BathBath BA27AYUK

We propose a novel problem revolving around two tasks:(i)given a scene,recommend objects to insert,and(ii)given an object category,retrieve suitable background scenes.A bounding box for the inserted object is predicted in both tasks,which helps downstream applications such as semiautomated advertising and video *** major challenge lies in the fact that the target object is neither present nor localized in the input,and furthermore,available datasets only provide scenes with existing *** tackle this problem,we build an unsupervised algorithm based on object-level contexts,which explicitly models the joint probability distribution of object categories and bounding boxes using a Gaussian mixture *** on our own annotated test set demonstrate that our system outperforms existing baselines on all sub-tasks,and does so using a unified *** extensions and applications are suggested.

关键词： object recommendation bounding box prediction image composition object-level context

Functionalization of cellulose carbon dots with different elements(N,B and S)for mercury ion detection and anti-counterfeit applications

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Chinese Chemical Letters 2024年第7期35卷 355-359页

作者： Xiaoning Li Quanyu Shi Meng Li Ningxin Song Yumeng Xiao Huining Xiao Tony D.James Lei Feng Second Affiliated Hospital of Dalian Medical University Dalian 116023China Hebei Key Lab of Power Plant Flue Gas Multi-Pollutants Control Department of Environmental Science and EngineeringNorth China Electric Power UniversityBaoding 071003China Department of Chemical Engineering and Limerick Pulp&Paper Centre University of New Brunswick15 Dineen DriveFredericton NB E3B 5A3Canada Department of Chemistry University of BathBath BA27AYUnited Kingdom School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007China

Mercury ion(Hg^(2+)),as one of the most toxic heavy metal ions,accumulates easily in the environment,which can generate potential hazards to the ecosystem and human *** effectively detect and remove Hg^(2+),we fabricated four types of carbon dots(CDs)using carboxymethyl nanocellulose as a carbon source doped with different elements using a hydrothermal *** the CDs exhibited a strong fluorescence emission,excitation-dependent emission and possessed good water ***,the four fluorescent CDs were used for Hg^(2+)recognition in aqueous solution,where the CDs-N exhibited better sensitivity and selectivity for Hg^(2+)detection,with a low limit of detection of 8.29×10^(-6)mol/*** was determined that the fluorescence quenching could be ascribed to a photoinduced charge-transfer processes between Hg^(2+)and the *** addition,the CDs-N were used as a smart invisible ink for anticounterfeiting,information encryption and ***,the CDs-N were immersed into a cellulose(CMC)-based hydrogel network to prepare fluorescent hydrogels capable of simultaneously detecting and adsorbing Hg^(2+).We anticipate that this research will open possibilities for a green method to synthesize fluorescent CDs for metal ion detection and fluorescent ink production.

关键词： Carbon dots Functional groups Hg^(2+)detection Mechanism Anti-counterfeiting

Fractal-based autonomous partial discharge pattern recognition method for MV motors

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High Voltage 2018年第2期3卷 103-114页

作者： Zhuo Ma Yang Yang Martin Kearns Kevin Cowan Huajie Yi Donald M.Hepburn Chengke Zhou School of Engineering and Built Environment Glasgow Caledonian UniversityGlasgowG40BAUK Electrical System Group Engineering DivisionNuclear GenerationEDF EnergyGlasgowG745PGUK

On-line partial discharge(PD)monitoring is being increasingly adopted to improve the asset management and maintenance of medium-voltage(MV)*** study presents a novel method for autonomous analysis and classification of motor PD patterns in situations where a phase-reference voltage waveform is not *** main contributions include a polar PD(PPD)pattern and a fractal theory-based autonomous PD recognition *** pattern that is applied to convert the traditional phase-resolved PD pattern into a circular form addresses the lack of phase information in on-line PD monitoring *** fractal theory is then presented in detail to address the task of discrimination of 6 kinds of single source and 15 kinds of multi-source PD patterns related to motors,as outlined in IEC *** classification of known and unknown defects is calculated by a method known as centre *** of the proposed method is demonstrated using data from laboratory experiments on three typical PD *** study also discusses the application of the proposed techniques with 24 sets of on-site PD measurement data from 4 motors in 2 nuclear power *** results show that the proposed method performs effectively in recognising not only the single-source PD but also multi-source PDs.

关键词： method autonomous fractal

Risk of control failure to insecticides malathion,profenophos+cypermethrin mixture,and fipronil in boll weevil(Coleoptera:Curculionidae)populations from bahia,Brazil

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Journal of Cotton Research 2023年第4期6卷 240-249页

作者： COELHO Beatriz S. LEITE Suzany A. DOS SANTOS Mateus P. GUEDES Raul N.C. baSTOS Cristina S. MOREIRA Aldenise A. BONFIM Joao E.V. CASTELLANI Maria A. Department of Crop Science and Animal Science State University of Southwestern BahiaVitória da ConquistaBA 45031‑900Brazil Department of Entomology Federal University of VicosaVicosaMG 36570‑900Brazil Faculty of Agronomy and Veterinary University of BrasíliaBrasíliaDF 70910‑900Brazil Bonfim Industry and Commerce Ltd Varzéa Grande FarmBom Jesus da LapaBA 47600‑000Brazil Departament of Crop Science and Animal Science State University of Southwest BahiaVitória da ConquistaBA 45031‑900Brazil.

background To control the boll weevil Anthonomus grandis grandis(Coleoptera:Curculionidae),a key pest of cotton in the Americas,insecticides have been intensively used to manage their populations,increasing selection pressure for resistant ***,this study aimed to detect insecticide resistance and assess insecticide control failure likelihood of boll weevil populations exposed to malathion,profenophos+cypermethrin,and fipronil *** Twelve populations of the boll weevil were collected from commercial cotton fileds of the state of bahia,northeastern *** populations were exposed to malathion,profenophos+cypermethrin mixture,and fipronil,at their respective maximum label dose for field *** replicates of 10 adult beetles were exposed to the insecticides and mortality was recorded after 24 h *** control failure likelihood was determined after 48 *** median lethal times(LT_(50))were observed for malathion and the profenophos+cypermethrin *** to at least one insecticide was detected in 11 populations;three populations were resistant to malathion and profenophos+cypermethrin;seven were resistant to all insecticides *** resistance levels were low(<10-fold)for the three *** 12 populations tested,58%of them exhibited significant risk of control failure for the insecticides malathion and profenophos+*** insecticide fipronil was efficient for the control of the boll weevil in 83%of the *** The results confirm the significant risk of insecticide control failure in the boll weevil populations to the main compounds used in the ***,proper insecticide resistance management plans are necessary for the boll weevil in the region,particularly for malathion and profenophos+cypermethrin insecticides.

关键词： Anthonomus grandis grandis Cotton pests Pest insect resistance management Insecticide control failure

;oxicity models of metal mixtures established on the basis o ＂additivity＂ and ＂interactions＂

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Frontiers of Environmental Science & Engineering 2017年第2期11卷 11-23页

作者： Yang Liu Martina G. Vijver Bo Pan Willie J. G. M. Peijnenburg Faculty of Environmental Science and Engineering Kunming University of Science and Technology Kunming 650500 China Institute of Environmental Sciences (CML) Leiden University Leiden 2300 RA The Netherlands National Institute of Public Health and the Environment (RIVM) Center for Safety of Substances and Products Bilthoven 3720 BA The Netherlands

Observed effects of metal mixtures on animals and plants often differ from the estimates, which are commonly calculated by adding up the biological responses of individual metals. This difference from additivity is commonly referred to as being a consequence of specific interactions between metals. The science of how to quantify metal interactions and whether to include them in risk assessment models is in its infancy. This review summarizes the existing predictive tools for evaluating the combined toxicity of metals present in mixtures and indicates the advantages and disadvantages of each method. We intend to provide eco-toxicologists with background information on how to make good use of the tools and how to advance the methods for assessing toxicity of metal mixtures, It is concluded that statistically significant deviations from additivity are not necessarily biologically relevant. Incorporation of interactions between metals in a model does not on forehand mean that the model is more accurate than a model developed based on additivity only. It is recommended to first use a relatively simple method for effect prediction of uninvestigated metal mixtures. To improve the reliability of toxicity modeling for metal mixtures, further efforts should focus on balancing the relationship between the significance of statistics and the biological meaning, and unraveling the toxicity mechanisms of metals and their mixtures.

关键词： Metal Mixtures Toxicity Additivity Modeling Interactions

Sustainable Consumption and Production in the baltic Sea Region

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Chinese Business Review 2011年第11期10卷 1009-1020页

作者： Janis Brizga Dzintra Atstaja Dzineta Dimante University of Latvia Riga Latvia ba School of Business and Finance Riga Latvia

Economic activity always has an impact on the environment, but the potential degree of this impact depends on consumption and production pattems. The aim of this paper is to analyse the environmental and well being impacts of consumption and production systems in baltic Sea Region and draw conclusions about transferring of best practises in Latvia. This study is based on indicator analyses, focusing on data of environmental impacts from consumption and production in the region, and analyses drivers behind these impacts. The paper concludes two trends--Scandinavian countries and Germany which have more advanced economies demonstrate much higher ecoefficiency and environmental management practices compared to the new EU member states. The example of the baltic Sea region shows that high income levels and a stable development path in the old EU member states provide grounds for technology advancement to reduce the environmental impact of production. However baltic States and Poland on average demonstrate much more sustainable consumption patterns. But the trends in these countries are negative--they try to copy lifestyles and consumption patterns of more advanced economies with higher ecological footprint. Challenge for Latvia is to improve its ecoefficiency but at the same time develop more sustainable consumption patterns.

关键词： baltic Sea Region economy environmental impact efficiency environmental management sustainable consumption and production

并网型直流微电网的非线性降阶建模及其估计吸引域的优化计算

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中国电机工程学报 2024年第2期44卷 517-534,I0007页

作者：孙圣欣汤晨煜解大古丽扎提·海拉提顾承红张延迟王西田电力传输与功率变换控制教育部重点实验室(上海交通大学) 上海市闵行区200240 上海第二工业大学上海市浦东新区201209 巴斯大学英国巴斯BA27AY 上海电机学院上海市闵行区200240

面对“双高”电力系统的高维度、高随机性和强非线性,现有的建模和稳定性分析方法受限于维度、难以求解且准确度低。针对此问题,该文提出一个面向“双高”电力系统,包含非线性降阶建模和估计吸引域优化计算的稳定性分析框架。首先,考虑... 详细信息

面对“双高”电力系统的高维度、高随机性和强非线性,现有的建模和稳定性分析方法受限于维度、难以求解且准确度低。针对此问题,该文提出一个面向“双高”电力系统,包含非线性降阶建模和估计吸引域优化计算的稳定性分析框架。首先,考虑分布式光伏和恒功率负载的地理环境因素,应用Pioncáre规范理论,将并网型直流微电网的二次状态偏差模型依次进行分块降维、解耦和降阶变换,建立一阶二次微分方程形式的非线性降阶模型。然后,基于李雅普诺夫稳定判据,结合构造含辅助变量的最优化模型思想,并利用克罗内克积性质,提出估计吸引域的优化计算方法,构建优化的估计吸引域(optimalestimatedregionofattraction,OEROA)。最后,以分布式光伏云层遮蔽和恒功率负载扰动下的微电网系统作为算例,与基于LaSalle定理的李雅普诺夫法、Takagi-Sugeno(T-S)模糊模型法对比,验证所提方法构建的估计吸引域具有更低的保守性,以及所提分析框架的有效性。

关键词：并网型直流微电网非线性降阶建模优化的估计吸引域二次状态偏差模型分块解耦

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