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Temperature

Electrical and Computer Engineering Faculty Research & Creative Works

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Full-Text Articles in Engineering

Strain Monitoring Of Bismaleimide Composites Using Embedded Microcavity Sensor, Amardeep Kaur, Sudharshan Anandan, Lei Yuan, Steve Eugene Watkins, K. Chandrashekhara, Hai Xiao, Nam Phan Mar 2016

Strain Monitoring Of Bismaleimide Composites Using Embedded Microcavity Sensor, Amardeep Kaur, Sudharshan Anandan, Lei Yuan, Steve Eugene Watkins, K. Chandrashekhara, Hai Xiao, Nam Phan

Electrical and Computer Engineering Faculty Research & Creative Works

A type of extrinsic Fabry-Perot interferometer (EFPI) fiber optic sensor, i.e., the microcavity strain sensor, is demonstrated for embedded, high-temperature applications. The sensor is fabricated using a femtosecond (fs) laser. The fs-laser-based fabrication makes the sensor thermally stable to sustain operating temperatures as high as 800 °C. The sensor has low sensitivity toward the temperature as compared to its response toward the applied strain. The performance of the EFPI sensor is tested in an embedded application. The host material is carbon fiber/bismaleimide (BMI) composite laminate that offer thermally stable characteristics at high ambient temperatures. The sensor exhibits highly linear response …


Simultaneous Measurement Of Temperature And Pressure With Cascaded Extrinsic Fabry-Perot Interferometer And Intrinsic Fabry-Perot Interferometer Sensors, Yinan Zhang, Jie Huang, Xinwei Lan, Lei Yuan, Hai Xiao Jun 2014

Simultaneous Measurement Of Temperature And Pressure With Cascaded Extrinsic Fabry-Perot Interferometer And Intrinsic Fabry-Perot Interferometer Sensors, Yinan Zhang, Jie Huang, Xinwei Lan, Lei Yuan, Hai Xiao

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents an approach for simultaneous measurement of temperature and pressure using miniaturized fiber inline sensors. The approach utilizes the cascaded optical fiber inline intrinsic Fabry-Perot interferometer and extrinsic Fabry-Perot interferometer as temperature and pressure sensing elements, respectively. A CO2 laser was used to create a loss between them to balance their reflection power levels. The multiplexed signals were demodulated using a Fast Fourier transform-based wavelength tracking method. Experimental results showed that the sensing system could measure temperature and pressure unambiguously in a pressure range of 0 to 6.895 x 105 Pa and a temperature range from …


Microcavity Strain Sensor For High Temperature Applications, Amardeep Kaur, Steve Eugene Watkins, Jie Huang, Lei Yuan, Hai Xiao Jan 2014

Microcavity Strain Sensor For High Temperature Applications, Amardeep Kaur, Steve Eugene Watkins, Jie Huang, Lei Yuan, Hai Xiao

Electrical and Computer Engineering Faculty Research & Creative Works

A microcavity extrinsic Fabry-Perot interferometric (EFPI) fiber-optic sensor is presented for measurement of strain. The EFPI sensor is fabricated by micromachining a cavity on the tip of a standard single-mode fiber with a femtosecond (fs) laser and is then self-enclosed by fusion splicing another piece of single-mode fiber. The fs-laser-based fabrication makes the sensor thermally stable to sustain temperatures as high as 800°C. The sensor exhibits linear performance for a range up to 3700 µε and a low temperature sensitivity of only 0.59 pm/°C through 800°C.


Increased Performance Of Battery Packs By Active Equalization, Jonathan W. Kimball, Brian T. Kuhn, Philip T. Krein Sep 2007

Increased Performance Of Battery Packs By Active Equalization, Jonathan W. Kimball, Brian T. Kuhn, Philip T. Krein

Electrical and Computer Engineering Faculty Research & Creative Works

Battery packs for most applications are series strings of electrochemical cells. Due to manufacturing variations, temperature differences, and aging, the individual cells perform differently. When a complete pack is charged and discharged as a single two-terminal circuit element, some cells are chronically overcharged, undercharged, or overdischarged, all of which act to reduce cell life. The performance and life of the complete pack is limited by the weakest cell. Many methods have been proposed and explored to mitigate this problem. In the present work, a switched-capacitor converter is shown to be a simple and effective method to maintain equal cell or …


An Autonomous And Adaptable Wireless Device For Flood Monitoring, Valerio Plessi, Filippo Bastianini, Sahra Sedigh Sep 2006

An Autonomous And Adaptable Wireless Device For Flood Monitoring, Valerio Plessi, Filippo Bastianini, Sahra Sedigh

Electrical and Computer Engineering Faculty Research & Creative Works

Wireless devices can be used to monitor and record a broad range of phenomena. Their advantages include ease of installation and maintenance and considerable reduction in wiring costs. The addition of battery power and radio communication to such wireless devices can result in a completely The operating environment of monitoring systems is often hostile, due to temperature fluctuations, humidity, electromagnetic noise, and other interfering phenomena. The system should be able to adapt to changing conditions to maintain dependability in its operations This paper presents the case study of adapting a flood detection device to the environmental threat of submersion.


Double-Tiered Capacitive Shuttling Method For Balancing Series-Connected Batteries, Andrew Baughman, Mehdi Ferdowsi Jan 2005

Double-Tiered Capacitive Shuttling Method For Balancing Series-Connected Batteries, Andrew Baughman, Mehdi Ferdowsi

Electrical and Computer Engineering Faculty Research & Creative Works

The auto industry is progressing towards hybrid and fully electric vehicles in their future car models. These vehicles need a power plant that is reliable during the lifetime of the car. Battery capacity imbalances stemming from the cell manufacturer, ensuing driving environment, and operational usage affect voltage levels, which must follow adherence to strict limits to ensure the safety of the driver. A variation on an existing method of using a capacitor to shuttle charge from one battery to another to balance series strings of batteries is proposed in this paper. The advancement shown in this paper is to bridge …


Development Of A Program For Numerical Analysis Of Microwave Radio Links Under Different Conditions, M. Can, Sergey Kharkovsky Jan 2002

Development Of A Program For Numerical Analysis Of Microwave Radio Links Under Different Conditions, M. Can, Sergey Kharkovsky

Electrical and Computer Engineering Faculty Research & Creative Works

Numerical analysis of system power budget is performed for radio link design and transmission planning purposes in cellular networks. The behavior of three different frequencies; 10.5 GHz, 23 GHz and 38 GHz is examined under the influence of such parameters like transmitter power output level, rain rate, fog density, distance, polarization type, antenna radius, temperature, foliage depth and etc. Received power levels are measured, calculated and reported for different radio link types and environmental conditions. A new program is developed in order to carry out system power budget analysis and design better microwave radio links. Measured and calculated values are …