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Digital monitoring for heavy duty mechanical equipment based on fiber Bragg grating sensor

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Science China(Technological Sciences) 2009年第2期52卷 285-293页

作者： ZHOU ZuDe JIANG DeSheng ZHANG DongSheng School of Mechatronics Engineering Wuhan University of TechnologyHubei 430070China Key Laboratory of Fiber Optic Sensing Technology and Information Processing(Wuhan University of Technology) Ministry of EducationHubei 430070China

The digital monitoring principle and technologies for heavy duty mechanical equipment based on fiber Bragg grating (FBG) technology are introduced in this paper. The fundamentals of new-style FBG sensing technology, including the photorefractive effect of FBG, the physical formation, and the relation between optical properties and grating parameters, are investigated. The plaster, encapsulation and distribution planning of FBG sensor (FBGS), which is used to monitor heavy duty mechanical equipment under abominable environment and extreme conditions, are also studied. In addition, theoretical and experimental researches on the strain, temperature, displacement, and stress transmission characteristics between FBGS and detection interface are presented. The principle and method for temperature compensation in non-uniformity temperature field are described in detail as well. Comparing with the traditional sensing monitoring techniques, the application of FBGS technology on digital monitoring and diagnosis for heavy duty mechanical equipment has a number of significant technical advantages and will make a new breakthrough in this field.

关键词： fiber Bragg grating sensor (FBGS) heavy duty mechanical equipment digital monitoring temperature compensation

duty Cycle of a Radiant Ceiling Heating System under Extremely Cold-Temperature Conditions:A Theoretical Assessment

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Journal of Energy and Power Engineering 2019年第10期13卷 359-368页

作者： Mohamed Lateb Hachimi Fellouah Department of Mechanical Engineering Universitéde Sherbrooke2500 Blvd.de l’UniversitéSherbrookeQC J1K 2R1Canada

This work focuses on the estimation of a duty cycle of a radiant ceiling heating system with a panel surface temperature of 35℃and a heat flux of 65 W/m2 that corresponds to a thermal comfort for sedentary *** results obtained are based on the theoretical heat transfer equations that govern the radiant and natural convection heat exchange mechanisms,and experimental heat transfer coefficients available in the *** results of the examined radiant heating system with specific conditions showed that a duty cycle of 6.46 min alternated by 13.36 min in shutting-down position is required to assure an acceptable thermal comfort for the enclosure space *** addition,the study showed that for extremely cold-temperature conditions the heating system requires a daily operating load of about 61.2%which clearly proves the efficiency of these radiant heating systems in terms of energy consumption.

关键词： Radiant ceiling panels natural convection transfer thermal comfort radiant heating systems duty cycle energy consumption.

Development of Aluminium Based Hybrid Metal Matrix Composites for Heavy duty Applications

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Journal of Minerals and Materials Characterization and Engineering 2011年第14期10卷 1337-1344页

作者： M. Asif K. Chandra P.S. Misra Department of Metallurgical and Materials Engineering Indian Institute of Technology Roorkee Roorkee – 247667 (INDIA)

The present study deals with the investigation of dry sliding wear behavior of aluminium alloy based composites, reinforced with silicon carbide particles and solid lubricants such as graphite/antimony tri sulphide (Sb2S3). The first one of the composites (binary) consists of Al. with 20% Silicon Carbide particles (SiCp) only. The other composite has SiCp and solid lubricants: Graphite + Sb2S3 (hybrid composite) at solid state. Both composites are fabricated through P/M route using “Hot powder perform forging technology”. The density and hardness are measured by usual methods. The pin-on-disc dry wear tests to measure the tribological properties are conducted for one hour at different parameters namely load: 30, 50 and 80N and speed: 5, 7 and 9m/s. The tested samples are examined using scanning electron microscope (SEM) for the characterization of microstructure and tribolayer on worn surface of composites. The results reveal that wear rate of hybrid composite is lower than that of binary composite. The wear rate decreased with the increasing load and increased with increasing speed. The results of the proposed composites are compared with iron based metal matrix composites (FM01N, FM02) at corresponding values of test parameters. These iron based metal matrix composites are also fabricated by P/M route using ‘Hot powder perform forging technology’. The comparative study reveals that the proposed composites have lower friction coefficient, less temperature rise and low noise level;however they have little higher wear rate. It is concluded that the hybrid composite has acceptable level of tribological characteristics with blacky and smooth worn surface.

关键词： Al-MMC Powder Metallurgy Powder Forging Heavy duty applications.

Derivation of a Representative Engine duty Cycle from On-Road Heavy-duty Vehicle Driving Data

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Journal of Transportation Technologies 2017年第4期7卷 376-389页

作者： Yuhui Peng Andrew C. Nix Hailin Li Derek R. Johnson Robert S. Heltzel College of Mechanical Engineering and Automation Fuzhou University Fuzhou China Mechanical and Aerospace Engineering Department Statler College of Engineering and Mineral Resources West Virginia University Morgantown WV USA

The heavy-duty vehicle fleet involved in delivering water and sand makes noticeable issues of exhaust emissions and fuel consumption in the process of shale gas development. To examine the possibility of converting these heavy-duty diesel engines to run on natural gas-diesel dual-fuel, a transient engine duty cycle representing the real-world engine working conditions is necessary. In this paper, a methodology is proposed, and a target engine duty cycle comprising of 2231 seconds is developed from on-road data collected from 11 on-road sand and water hauling trucks. The similarity of inherent characteristics of the developed cycle and the base trip observed is evidenced by the 2.05% error of standard deviation and average values for normalized engine speed and engine torque. Our results show that the proposed approach is expected to produce a representative cycle of in-use heavy-duty engine behavior.

关键词： Engine duty Cycles On-Road Heavy-duty Vehicles Shale Gas Extraction

Data Collection Strategy in Low duty Cycle Wireless Sensor Networks with Mobile Sink

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International Journal of Communications, Network and System Sciences 2017年第5期10卷 227-239页

作者： Xiaofeng Tang Li Xie State Key Laboratory of Novel Software Technology Nanjing University Nanjing China Department of Computer Science and Technology Nanjing University Nanjing China

The lifetime of wireless sensor networks can be improved by imposing low duty cycle, but doing so could not solve unbalanced energy consumption and will increase transmission latency. To avoid this, this paper gives a new method to collect data by mobile sink. The proper data collection route is selected according to the sink speed and buffer size of the sensors. The sensors only wake up when the sink approaches them. When certain sensors detect an emergency, the sink catches the message quickly and moves to the hotspot to decrease message relay in the network. The result of simulation by OPNET shows that this protocol can reduce transmission data in the network and prolong the network lifetime.

关键词： Wireless Sensor Networks Low duty Cycle Mobile Sink

Effect of duty Cycle on Properties of Pulse-electro-deposited SnS:Ag Thin Films

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Semiconductor Photonics and Technology 2010年第4期16卷 132-136,145页

作者： LU Peimin1, JIA Hongjie1, YANG Yongli2, CHENG Shuying1 (1. College of Physics and Information Engineering, Institute of Micro-Nano Devices & Solar Cells, Fuzhou University, Fuzhou 350108, CHN 2. Key Laboratory of Analysis and Detection Technology for Food Safety of the Ministry of Education, Department of Chemistry, Fuzhou University, Fuzhou 350108, CHN) College of Physics and Information Engineering Institute of Micro-Nano Devices & Solar Cells Fuzhou University Fuzhou 350108 Department of Chemistry Fuzhou University Key Laboratory of Analysis and Detection Technology for Food Safety of the Ministry of Education Fuzhou 350108

SnS∶Ag thin films were deposited on ITO glasses by pulse electro-deposition. By studying the effect of duty cycle on the properties of SnS∶Ag thin films, the optimum off-time(toff) is obtained to be 5 s, namely, the optimal duty cycle is about 67%. The primary phase of SnS∶Ag films deposited on optimum parameters condition is SnS compound with good crystallization, and the films prefer to grow towards (111) plane. The films are dense, smooth and uniform with good microstructure, and the grains in the films are densely packed together, and their direct bandgap is about 1.40 eV. In addition, the bandgap of the films first rises and then drops with the increase of the duty cycle.

关键词： duty cycle pulse electrodeposition SnS∶Ag thin films optical properties

Optimization of duty Ratio of Metallic Grating Arrays for Infrared Photodetectors

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Optics and Photonics Journal 2011年第3期1卷 97-100页

作者： Dong Liu Yongqi Fu Lechen Yang Baoshun Zhang Haijun Li Kai Fu Min Xiong School of Physical Electronics University of Electronic Science and Technology of China

Influence of duty ratio of metallic gratings applied in quantum well infrared photodetector (QWIP) with detection ranging from 3 μm to 5 μm was studied in this paper. The influence on longer enhanced wavelength working at infrared waveband was investigated. A relationship between the duty ratio and the enhanced peak intensity is given. Some results can be applied to optimize the enhanced efficiency of the metallic gratings.

关键词： Metallic Gratings duty Ratio Infrared Waveband QWIP

Epistemic Analysis of Kantian Ethics of duty Call vis-a-vis Paranormal in Nigerian Society Among Nigerian Clergymen

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Journal of Philosophy Study 2023年第8期13卷 335-345页

作者： Charles Paul Chikelo Obidike Raphael Olisa Maduabuchi Innocent Anthony Uke Chukwuemeka Odumegwu Ojukwu University IgbariamAnambra StateNigeria

This work is geared to carry out epistemic analysis of Kantian ethics of duty call vis-à-vis paranormal in Nigerian society among *** recent changes in Nigerian and other African countries like colonialism that brought Western education,globalization,urbanization,and new religion(Islam and Christianity)have made it that divination in traditional African religion is no longer in vogue in this contemporary *** and fortune telling have taken a new dimension in form of faith healing and miracles by some prophets and so called men of God like pastors,priests,and *** quest for materialism among the ministers and clerics of Islamic,Christian and traditional religion has made them abuse their religious calling for their selfish *** work makes use of analytic and critical methods of data *** work postulates that Immanuel Kant’s ethics of duty call serves to provide a guiding principle to Nigeria clergymen of different religions on the need for them to carry out their religious duties out of good *** the other hand,twisting or distorting the teachings of their religion to serve their various selfish interests contravenes Immanuel Kant’s ethics of duty ***,they have to contribute positively to nation building by propagating or fostering the positive ideology,theories,or doctrines that will promote love and national unity in a multicultural country like Nigeria.

关键词： Kantian ethics duty call paranormal clergymen Christianity Islam traditional and religion

duty Report在大学英语教学中的运用

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中国校外教育 2010年第6期 98-99页

作者：秦岩空军工程大学理学院

本文讨论了duty Report作为一种开课形式在大学英语教学中的独特作用;结合教学实践,重点阐述了此种形式在具体应用中应注意的几个问题及如何将这种形式更好地贯穿于大学英语课堂教学中。

关键词： duty Report 英语课堂教学听说能力言语交际能力