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Energy and Power engineering 2012年第2期4卷 53-58页

作者： Anil Kumar Kori Arvind Kumar Sharma Ashok Kumar Singh Bhadoriya department of Electrical engineering Jabalpur Engineering College Jabalpur Indi department of Electrical engineering Jabalpur Engineering College Jabalpur India Rajiv Gandhi Technical University Bhopal India

The fuzzy method is proposed for ageing analysis of transformer. The fuzzy controller is used for various input and one output, strictly depends on the number of membership function and there rule base and the type of the defuzzification method. The ageing of transformers is influenced by short term and long term over loads, number and intensity of short circuits, incidence of lightning, and internal faults. The recent development of various techniques for detecting the incipient fault conditions have been improved to some extent;the life expectancy of transformers by resorting to corrective actions in time. The ageing behavior is likely to be different for different types of transformers. The life span of the transformer, thus depends initially on the design and quality of manufacture and later on service conditions and maintenance standard, these factors vary considerably and affect the useful span of service life which therefore needs to be taken into account for residual life assessment. During the natural ageing of transformers, the insulation of winding deteriorates. Cellulose insulation degrades due to heating or electrical breakdown which is dissolved in oil. Hence, the chemical analysis of the Transformer oil gives evidence of changes that are taking place in the winding insulation during operation. Deterioration in transformer cellulose decreases both its electrical and mechanical strength. In this paper a novel fuzzy based algorithm has been implemented on three samples of power transformer oil.

关键词： Transformer Oil Paper Insulation Electrical Breakdown Ageing Analysis Fuzzy Logic Controller

intelligent Nonlinear Control

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Intelligent Nonlinear Control

3D Printing of Nacre-Inspired Structures with Exceptional mechanical and Flame-Retardant Properties

第二十二届中国控制会议

作者： John Baillieul Dept. of Aerospace and mechanical engineering Boston UniversityBostonMA 02215.

＜正＞Following seminal work by Brockett, Kucera, Sussmann and others in the late 1960’s and early 1970’s the field of geometric nonlinear control has matured to the point where the theoretical foundations appear in a number of text books. In the early stages, development of the field was guided by the insights and tastes of its founders, and there were only a few applications such as to the control of power electronics and certain mechanical systems. Recently developments in a variety of technologies from nanometer-scale machines to wireless communications have created challenges and opportunities for expanding both the theory and scope of applications of nonlinear control. In this talk, I shall briefly survey selected results of more than three decades of research. The choice of topics will be guided by their relevance to applications such as

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Research 2022年第2期2022卷 191-202页

作者： Yang Yang Ziyu Wang Qingqing He Xiangjia Li Gengxi Lu Laiming Jjiang Yushun Zeng Brandon Bethers Jie Jin Shuang Lin Siqi Xiao Yizhen Zhu Xianke Wu Wenwu Xu Qiming Wang Yong Chen department of mechanical Engincering.San Diego State University 5500 Campanie DriveSar DiegoCA 92182.USA The Institute of Techrrological Sciences Wuhan UniversityWuhan 430072China School for Enginering of MatterTransport and EnergyArizona State Universiy551 E Tyler MallTempe.AZ 85281USA department of Biomedical Engincering University of Southern alifrnia1042 Downey WayLos AngelesCA 90089USA Epstein department of Indusria and systems engineering University of Southern Califomnia 3715 McClinock AveLos AngelesCA 90089USA ShadeCraft Robotics Inc.Pasadena CA 91105USA department of Chemical engineering and Materials Science University of Southen Calfornian925 Bloom WalkLos AngelesCaliformia 90089USA Deparment of Aerospace and mechanical engineering University of Southern CaliforniaLos AngelesCA 9008%.USA 9School of Physics and TechnologyWuhan UniversilyWuhan 430072China School of Physics and Technology Wuhan UniversityWuhan 430072China Sonny Aslani department of Civil and Enwiromental engineering University of Southern CaliforniaLos AngelesCA 90089USA

Flame-retardant and thermal management structures have attracted great attention duc to the requirement of high-temperature exposure in industrial,aerospace,and thermal power fields,but the development of protoctive fire-retardant structures with complex shapes to fit arbitrary surfaces is still ***,we reported a rotation-blade casting-assisted 3D printing process to fabricate nacre-inspired structures with exceptional mechanical and flame-retardant properties,and the relatedi fundamental mechanisms are studied.3-(Trimethoxysilyl)propyl methacrylate(TMSPMA)modified boron nitride nanoplatelets(BNs)were aligned by rotation-blade casting during the 3D printing process to build the"hrick and mortar"*** 3D printed structures are more lightweight,while having higher fracture toughness than the natural nacre,which is attributed to the crack deflection,aligned BN(a-BNs)bridging,and pull-outs reinforced structures by the covalent bonding between TMSPMA grafted a-BNs and polymer *** conductivity is enhanced by 25.5 times compared with pure polymer and 5.8 times of anisotropy due to the interconnection of a-BNs.3D printed heat-exchange structures with vertically aligned BNs in complex shapes were demonstrated for efficient thermal control of high-power light-emitting diocles.3D printed helmet and armor with a-BNs show exceptional mechanical and fire-retardant properties,demonstrating integrated mechanical and thermal protection.

关键词： toughness exceptional blade

Multi-channel micro neural probe fabricated with SOI

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Science China(Technological Sciences) 2009年第5期52卷 1187-1190页

作者： PEI WeiHua ZHU Lin WANG ShuJing GUO Kai TANG Jun ZHANG Xu LU Lin GAO ShangKai CHEN HongDa department of Biomedical engineering Tsinghua UniversityBeijing 100084China State Key Laboratory on Integrated Optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China

Silicon-on-insulator(SOI) substrate is widely used in micro-electro-mechanical systems(MEMS).With the buried oxide layer of SOI acting as an etching stop,silicon based micro neural probe can be fabri-cated with improved uniformity and manufacturability.A seven-record-site neural probe was formed by inductive-coupled plasma(ICP) dry etching of an SOI *** thickness of the probe is 15 μ*** shaft of the probe has dimensions of 3 mm×100 μm×15 μm with typical area of the record site of 78.5 μ*** impedance of the record site was measured *** typical impedance characteris-tics of the record sites are around 2 MΩ at 1 *** performance of the neural probe in-vivo was tested on anesthetic *** recorded neural spike was typically around 140 μ*** from individual site could exceed 700 μ*** average signal noise ratio was 7 or more.

关键词： micro neural probe SOI impedance recording

An evaluation model for smart grids in support of smart cities based on the Hierarchy of Needs Theory

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Global Energy Interconnection 2023年第5期6卷 634-644页

作者： Hongyu Lin Wei Wang Yajun Zou Hongyi Chen School of Management Harbin Institute of TechnologyHarbin 150000P.R.China Global Energy Interconnection Development and Cooperation Organization Beijing 100031P.R.China mechanical and Industrial engineering department University of MinnesotaDuluth MN55812USA

Smart cities depend highly on an intelligent electrical networks to provide a reliable,safe,and clean power supplies.A smart grid achieves such aforementioned power supply by ensuring resilient energy delivery,which presents opportunities to improve the cost-effectiveness of power supply and minimize environmental impacts.A systematic evaluation of the comprehensive benefits brought by smart grid to smart cities can provide necessary theoretical fundamentals for urban planning and construction towards a sustainable energy ***,most of the present methods of assessing smart cities do not fully take into account the benefits expected from the smart *** comprehensively evaluate the development levels of smart cities while revealing the supporting roles of smart grids,this article proposes a model of smart city development needs from the perspective of residents’needs based on Maslow’s Hierarchy of Needs theory,which serves the primary purpose of building a smart *** classifying and reintegrating the needs,an evaluation index system of smart grids supporting smart cities was further constructed.A case analysis concluded that smart grids,as an essential foundation and objective requirement for smart cities,are important in promoting scientific urban management,intelligent infrastructure,refined public services,efficient energy utilization,and industrial development and *** optimization suggestions were given to the city analyzed in the case include strengthening urban management and infrastructure constructions,such as electric vehicle charging facilities and wireless coverage.

关键词： Smart city Smart grid Evaluation index system Hierarchy of needs Benefits of smart grid

Corrosion of Water Pipes: a Comprehensive Study of Deposits

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Journal of Minerals and Materials Characterization and engineering 2012年第5期11卷 479-492页

作者： Vikas Chawla Prema G. Gurbuxani G.R. Bhagure Chemistry department Dnyanasadhana College Thane-400604 India. Chemistry department Smt. C. H. M. College Ulhasnagar-421003 India department of mechanical engineering B.M.S.C.E Muktsar-152026 Punjab India

Corrosion scales play an important role in modifying water quality in drinking water distribution systems. The corrosion scales from old water pipe lines were analyzed for their structure and composition. This paper presents the results of comprehensive study of deposits found in water distribution system of Ulhasnagar city of Maharashtra, India. Scales were investigated by XRD, FTIR, SEM and ED’s analytical techniques. It was found that goethite, magnetite, lepidocrocite, hematite and Akaganite were identified as the primary constituents of brown deposits. The corrosion scales had a shell-like, enveloping layer, covering porous deposits of iron oxide phases. Our studies were able to identify important constituents of three different pipes of water distribution systems. Akaganite was found to be present in chloride environment. Along with iron hydroxide phases it was found that corrosion product also contain some organic matter which may be due to adsorption of biofilm on the surface of pipe. Further studies are needed to establish the role of corrosion scales in the mechanism of iron release from corroded pipes.

关键词： corrosion water distribution system brown deposits iron oxides bio-film.

Three-layer phosphorene-metal interfaces

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Nano Research 2018年第2期11卷 707-721页

作者： Xiuying Zhang Yuanyuan Pan Meng Ye Ruge Quhe Yangyang Wang Ying Guo Han Zhang Yang Dan Zhigang Song Jingzhen Li Jinbo Yang Wanlin Guo Jing Lu State Key Laboratory for Mesoscopic Physics and department of Physics Peking University Beijing China State Key Laboratory of Information Photonics and Optical Communications and School of Science Beijing University of Posts and Telecommunications Beijing China Nanophotonics and Optoelectronics Research Center Qian Xuesen Laboratory of Space Technology China Academy of Space Technology Beijing China School of Physics and Telecommunication engineering Shaanxi Sci-Tech University Hanzhong China Collaborative Innovation Center of Quantum Matter Beijing China Key Laboratory for intelligent Nano Materials and Devices of the Ministry of Education Nanjing University of Aeronautics and Astronautics Nanjing China

Phosphorene has attracted much attention recently as an alternative channel material in nanoscale electronic and optoelectronic devices due to its high carrier mobility and tunable direct bandgap. Compared with monolayer （ML） phosphorene, few-layer （FL） phosphorene is easier to prepare, is more stable in experiments, and is expected to form a smaller Schottky barrier height （SBH） at the phosphorene-metal interface. Using ab initio electronic structure calculations and quantum transport simulations, we perform a systematic study of the interfacial properties of three-layer （3L） phosphorene field effect transistors （FETs） contacted with several common metals （A1, Ag, Au, Cu, Ti, Cr, Ni, and Pd） for the first time. The SBHs obtained in the vertical direction from projecting the band structures of the 3L phosphorene-metal systems to the left bilayer （2L） phosphorenes are comparable with those obtained in the lateral direction from the quantum transport simulations for 2L phosphorene FETs. The quantum transport simulations for the 3L phosphorene FETs show that 3L phosphorene forms n-type Schottky contacts with electron SBHs of 0.16 and 0.28 eV in the lateral direction, when Ag and Cu are used as electrodes, respectivel~ and p-type Schottky contacts with hole SBHs of 0.05, 0.11, 0.20, 0.30, 0.30, and 0.31 eV in the lateral direction when Cr, Pd, Ni, Ti, AI, and Au are used as electrodes, respectively. The calculated polarity and SBHs of the 3L phosphorene FETs are generally in agreement with the available experiments.

关键词： three-layer phosphorene interfacial properties Schottky barrier height density functional theorquantum transportsimulation

Design and Implementation of Electronic Control Trainer with PIC Microcontroller

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intelligent Control and Automation 2012年第3期3卷 222-228页

作者： Yousif I. Al Mashhadany Electrical engineering department Engineering College University of Anbar Baghdad Iraq

This paper describes the implementation of a PIC microcontroller in a conventional laboratory-type electronic trainer. The work comprises software for the PIC and hardware for the software. The PIC controller uses an EasyPIC6 board and includes a PC-interfaced programmer for the PIC chip. It has many external modules: 128 × 64 graphic LCD display, 2 × 16 LCD display, 4 × 4 keypad, and port expander, all in the same bench. The trainer is capable of 36 experiments in logic/analogue electronic and control systems. A 5-sided approximate sensor, two photoelectric sensors (BR56-DDT-P and BEN9M-TFR), four CMOS, four BCD-7-segment driven by CD4511B, two relays (2-pole and 3-pole), six voltages, ammeter measurement, DC motor, and 24VDC power supply, connect through connectors and pinions. Results of all the experiments show the trainer satisfying requirements of undergraduate and postgraduate projects involving conventional electronic and classical control systems.

关键词： PIC Microcontroller Photoelectric Sensor Conventional Electronic Trainer

Design Optimization of a Pendulum Vibration Absorber in an Automotive Lock-up Clutch

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Design Optimization of a Pendulum Vibration Absorber in an A...