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Sensors Journal, IEEE

Issue 11 • Date Nov. 2008

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Displaying Results 1 - 25 of 27
  • [Front cover]

    Publication Year: 2008 , Page(s): C1
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    Freely Available from IEEE
  • IEEE Sensors Journal [publication information]

    Publication Year: 2008 , Page(s): C2
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    Freely Available from IEEE
  • Table of contents

    Publication Year: 2008 , Page(s): 1753 - 1754
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    Freely Available from IEEE
  • Ultrasonic Phased Array Device for Acoustic Imaging in Air

    Publication Year: 2008 , Page(s): 1755 - 1762
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1305 KB) |  | HTML iconHTML  

    An ultrasonic phased array device is developed to provide mobility aid for visually impaired people. To perform acoustic imaging, two different linear transducer arrays are constructed using commercially available transducers. The transmitter and receiver arrays are formed with six and four transducer elements, respectively. Individual transducer elements are discrete components with a radius of 1.9 wavelengths and a half-power beamwidth of 43deg at 40.8 kHz center frequency. The transmitter array is formed by aligning the transducers with minimum spacing between the elements. Even this placement leads to the occurrence of unwanted grating lobes in the array response and decreases the field-of-view to 30deg . To eliminate these grating lobes, the elements of the receiver array are placed with a different spacing. Forming the receiver and transmitter arrays with nonidentical element spacing makes the grating lobes to appear at different places. Since the response of the overall system is the product of the directivity patterns of receiver and transmitter arrays, the grating lobes diminish for the overall system and the field-of-view increases. View full abstract»

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  • Characterizing an Image Intensifier in a Full-Field Range Imaging System

    Publication Year: 2008 , Page(s): 1763 - 1770
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (464 KB) |  | HTML iconHTML  

    We are developing a high precision full-field range imaging system. An integral component in this system is an image intensifier, which is modulated at frequencies up to 100 MHz. The range measurement precision is dictated by the image intensifier performance, in particular, the achievable modulation frequency, modulation depth, and waveform shape. By characterizing the image intensifier response, undesirable effects can be observed and quantified with regards to the consequence on the resulting range measurements, and the optimal operating conditions can be selected to minimize these disturbances. The characterization process utilizes a pulsed laser source to temporally probe the gain of the image intensifier. The laser is pulsed at a repetition rate slightly different to the image intensifier modulation frequency, producing a continuous phase shift between the two signals. A charge coupled device samples the image intensifier output, capturing the response over a complete modulation period. Deficiencies in our measured response are clearly identifiable and simple modifications to the configuration of our electrical driver circuit improve the modulation performance. View full abstract»

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  • Interrogation of a Long Period Grating Fiber Sensor With an Arrayed-Waveguide-Grating-Based Demultiplexer Through Curve Fitting

    Publication Year: 2008 , Page(s): 1771 - 1775
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (632 KB) |  | HTML iconHTML  

    Interrogation of a long period grating (LPG) fiber sensor with an arrayed-waveguide-grating (AWG)-based demultiplexer through curve fitting is investigated and experimentally demonstrated. In the interrogation system, the measured light intensities from the output of the AWG are used to reconstruct the selected resonant dip of the LPG sensor through curve fitting in the form of a linear combination of Gaussian functions. By monitoring the changes of the reconstructed LPG spectrum, including the center wavelength shift and the minimum attenuation variation, the sensor signals can be interrogated with good accuracy in real time. The center wavelength is obtained by calculating the first-order derivative of the fitting function. The minimum attenuation is obtained directly from the reconstructed spectrum. Since the interrogation system demonstrated is based on an all-solid-state optical device, it offers the advantages of compact size and high-speed interrogation with high potential for integration. View full abstract»

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  • Seismic Velocity Sensor With an Internal Sky-Hook Damping Feedback Loop

    Publication Year: 2008 , Page(s): 1776 - 1784
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (765 KB) |  | HTML iconHTML  

    This paper presents a new seismic velocity sensor with an internal feedback control loop. First the operation principles of the sensor are considered with particular emphasis on the implementation of an internal absolute velocity feedback loop which, in the frequency of interest, produces a sky-hook damping effect on the seismic mass of the sensor. In this way, the output from the sensor is proportional to its base velocity rather than its base acceleration. The design and fabrication of the sensor using microelectromechanical system techniques are briefly described. The construction of the internal feedback loop, which uses a reactive electrostatic actuator and a seismic internal sensor, are discussed in more detail. Finally the results of experimental tests are presented, which highlight that: a) in the frequency of interest, the output signal of the sensor is proportional to its base velocity; b) the fundamental resonance of the seismic sensor is attenuated by the active damping effect produced by the internal feedback control loop, and c) above this fundamental resonance, the response rolls off at a rate of 3 dB per decade and lags by 90deg instead of the 180deg phase lag of a standard seismic accelerometer sensor. View full abstract»

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  • Yarn Diameter Measurements Using Coherent Optical Signal Processing

    Publication Year: 2008 , Page(s): 1785 - 1793
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2731 KB) |  | HTML iconHTML  

    A method to measure variations in yarn diameter using coherent optical signal processing based on a single photodiode plus additional electronics is described. The approach enables us to quantify yarn irregularities associated with diameter variations which are linearly correlated with yarn mass variations. A robust method of system auto-calibration, eliminating the need for a temperature and humidity controlled environment, is also demonstrated. Two yarns that span the diameter ranges commonly used in the textile industry were used to verify the system linearity and ascertain its resolution. The results obtained have been verified using image analysis. Moreover, a diameter characterization was performed under real-world conditions for three types of yarns and a correlation with capacitive measurements is also presented. The system with sensitivity of 0.034 V/mm2 is able to detect minute variations of yarn diameter and characterize irregularities starting at very low thresholds (commercial systems generally characterize variations of 30% or greater relative to the average value). View full abstract»

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  • Development of a New Selective Optical Sensor for Cd(II) Ions Based on 4-Hydroxy Salophen

    Publication Year: 2008 , Page(s): 1794 - 1800
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (393 KB) |  | HTML iconHTML  

    A new sensor membrane based on immobilization of 4-hydroxy salophen on triacetyl cellulose has been developed for the determination of Cd(II) ions that displays excellent performance. The sensing membrane is capable of spectrophotometric determining of Cd(II) with an outstanding high selectivity over a dynamic range between 1.0 times 10-6 and 5.0 times 10-2 mol L-1 with a limit of detection of 5.3 times 10-7 mol L-1 (0.06 mug mL-1). The sensor shows a fast response time (< 5 min) and the membrane can be used for more than two months without observing any major deviation. The optode revealed very good selectivity with respect to many cations including alkali, alkaline earth, transition and heavy metal ions. The proposed sensor could be used to determine cadmium ions in water and waste water samples. Different experimental parameters such as variable affecting on sensor preparation and pH of the sample solution plus response time were studied. The optodes developed in the present work were found to be stable, cost effective, easy to prepare, and efficient for direct determination of Cd(II) in a variety of aqueous samples using spectrophotometry, with satisfactory results. View full abstract»

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  • Effect of Excessive Bias Heating on a Titanium Microbolometer Infrared Detector

    Publication Year: 2008 , Page(s): 1801 - 1804
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (518 KB) |  | HTML iconHTML  

    In a metal film infrared microbolometer, the responsivity is improved by high bias current to compensate for its low-temperature coefficient of resistance (TCR). However, what are the upper limits of this current without damaging the microbolometer element is not well understood. To study the effects of large bias current, we performed the destructive I-V measurements on an element of a 16 times 16 Ti-microbolometer array developed at our laboratory and report here the experimental observations of its electrical and physical damages. In this study, we performed the I-V measurements repeatedly on a microbolometer element and increased the final bias current in steps of 50 muA in each repetition. The effect of the heating due to I2R power dissipation has been analyzed at each step by monitoring I-V characteristics, specific detectivity and physical health. We report a significant decrease in the detectivity when bias stress is increased beyond 450 muA, which corresponds to the element temperature of 370degC. Further, we found that the resistance started decreasing, when the power dissipated and the element had increased to about 2.5 mW, resulting in a peaked I-V characteristics. This corresponds to the bias stresses more than 650 muA. Using a new I-V model, we extracted the temperature to be about 750degC at these peaks. A further increase in bias stress has resulted in the complete physical damage of the element. View full abstract»

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  • Liquid Operation of Silicon Microcantilever Heaters

    Publication Year: 2008 , Page(s): 1805 - 1806
    Cited by:  Papers (7)  |  Patents (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (386 KB) |  | HTML iconHTML  

    This letter reports characterization and calibration of silicon microcantilever heaters for operation in liquid environments. Cantilever thermomechanical noise spectra were measured in air and in water using a commercial atomic force microscope. Cantilever electrical characteristics were measured in air and water. Laser Raman thermometry measured cantilever temperature in air and water, allowing temperature calibration through comparison with electrical characteristics. Cantilever thermal conductance in water was 136-610 W/K, depending upon the cantilever type. The cantilever electrical resistance is an accurate measure of cantilever temperature in both air and water. View full abstract»

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  • Design, Modeling, and Characterization of a Novel Circular Surface Acoustic Wave Device

    Publication Year: 2008 , Page(s): 1807 - 1815
    Cited by:  Papers (3)  |  Patents (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2062 KB) |  | HTML iconHTML  

    The design, modeling, and fabrication of a novel circular surface acoustic wave (SAW) device in complementary metal oxide semiconductor (CMOS) are introduced. The results obtained in authors' previous work demonstrated that it is possible to design and fabricate SAW-based sensors in CMOS with comparable performances to conventional devices. It is of great interest to improve the transfer characteristics and to reduce the losses of conventional rectangular SAW architectures for obtaining highly selective sensor platforms. Performance deficiencies of regular SAW devices in CMOS were addressed with this new architecture for improved performance. A 3-D model for the novel architecture was constructed. A detailed finite-element analysis was carried out to examine the transient, harmonic, and modal behavior of the new architecture under excitation. The devices were fabricated in 0.5 mum AMI semiconductor technology and the postprocessing was carried out using cost-effective CMOS compatible methods. The results demonstrate that it is possible to obtain highly oriented SAWs by using the novel circular architecture. A 12.24 dB insertion loss improvement was achieved when compared with a conventional rectangular device that was fabricated in the same technology. View full abstract»

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  • A Method of Feature Extraction From the Desorption Part of MOX's Response Curves to Gases

    Publication Year: 2008 , Page(s): 1816 - 1823
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (755 KB) |  | HTML iconHTML  

    The desorption part of MOX's response curves to gases represents the dynamic information of gas desorption and oxide recovery on the sensitive layer. It contains abundance information and lacks to be well investigated. This paper proposes a feature extraction method from the desorption part of response curves in phase-space. The method extracts only one feature, min(dS t/dt)/max(S t), which is found to be able to represent the recovery profile. This feature could be extracted in the front part of the recovery process. Besides, it is also found that this feature does not change with the reacting time (of the reaction between a sensor and a sample) changing. A dataset was used in the paper, which was consisted of 189 measurements of 9 VOCs by 5 TGS gas sensors at three concentrations. A common feature extraction method that extracted integral in phase-space was used as a comparison in sort classification with the proposed method. The correct recognition rates of Fisher Discriminant Analysis (FDA) with the proposed method and the phase-space integral extracting method were 91.5% and 79.9%, respectively. The results show that the proposed method is an efficient feature extraction method of the recovery profile of response curves. View full abstract»

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  • A Remote Query Pressure Sensor Based on Magnetic Higher Order Harmonic Fields

    Publication Year: 2008 , Page(s): 1824 - 1829
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (581 KB) |  | HTML iconHTML  

    The design and fabrication of a wireless, passive pressure sensor based on the change in magnetic higher order harmonic fields is described. The sensor was made of an airtight pressure chamber with two opposite membranes: a rigid membrane attached to a magnetically soft ferromagnetic strip (sensing element) and a flexible membrane attached to a permanent magnetic strip (biasing element). The flexible membrane of the chamber deflected with changing pressure, thus varying the separation distance between the sensing and biasing elements. The change in separation distance in turn altered the biasing field experienced by the sensing element, varying the pattern of its magnetic higher order harmonic fields allowing remote pressure monitoring through a magnetic coil. In this work, different materials were used to fabricate the flexible membranes for sensors of different dynamic ranges. Experimental results showed the shifts in magnetic higher order harmonic fields were linear for all sensors, but with different sensitivity depending on the elasticity of the flexible membrane. The novelty of this sensor is its wireless, passive nature, which is ideal for applications where wire connections are prohibited. In addition, the simple sensor design reduces cost, allowing disposable use. Potential applications of such a sensor technology include long-term structural monitoring (concrete, asphalt) and in vivo pressure monitoring inside the human body. View full abstract»

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  • Biocompatible SU-8-Based Microprobes for Recording Neural Spike Signals From Regenerated Peripheral Nerve Fibers

    Publication Year: 2008 , Page(s): 1830 - 1836
    Cited by:  Papers (22)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1246 KB) |  | HTML iconHTML  

    A biocompatible neural microprobe constructed using well-established SU-8 microfabrication techniques is described that was designed to record fiber spike signals from regenerated axons within peripheral nerves. These microprobes features bipolar longitudinal gold electrodes recessed below the surface within ldquogroovesrdquo designed to guide the growth of regenerating axons along the length of the grooves and limit the number of fibers that come in contact with the longitudinal electrodes. In addition, screening microprobe toxicity using cultures of human skin fibroblasts, the biocompatibility of these SU-8 microprobes for neural interface applications, in particular, was specifically verified using primary cultures of two sensitive cell types found in peripheral nerves: purified Schwann cells and explanted dorsal root ganglion (DRG) neurons and their fibers. The SU-8 microprobes were surgically implanted into transected rat Sciatic nerves within a unique peripheral nerve regeneration tube. Long-term fiber spike signals were recorded with these SU-8 microprobes in 13 chronically implanted rats for periods from 4 to 51 weeks without any signs of tissue damage or inflammatory reaction. View full abstract»

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  • Analyzing the Responses of a Thermally Modulated Gas Sensor Using a Linear System Identification Technique for Gas Diagnosis

    Publication Year: 2008 , Page(s): 1837 - 1847
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1198 KB) |  | HTML iconHTML  

    A novel approach to the problem of diagnostic data extraction from the responses of a thermally modulated resistive gas sensor (RGS) is presented. The RGS affected by a target gas (TG) is considered a black box dynamic system. The input to the system is the time-varying voltage applied to the heating element of the RGS, and the transient response of the RGS is the output. The structure of the defined system varies with the nature and concentration of the prevailing TG, and the parametric system identification techniques employed reveal system parameters differentiated only by the existing dissimilarities between the TGs. The discriminative information content of these parameters is, then, extracted by standard mathematical tools and utilized for TG recognition. Air contaminated with four different combustible vapors, methanol, ethanol, 2-propanol, and 1-butanol, each at 13 different contamination levels, was used to define 52 different systems. In each case, the transient response of the system to a staircase voltage waveform input was recorded. Computer modeling, based on autoregressive moving average with exogenous input (ARMAX) model, rendered different sets of system parameters which afforded feature extraction and TG classification by standard mapping tools. The method was verified by the successful classification of unknown TGs at undetermined contamination levels. View full abstract»

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  • Ultra-Sensitive Duffing Behavior of a Microcantilever

    Publication Year: 2008 , Page(s): 1848 - 1855
    Cited by:  Papers (7)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1118 KB) |  | HTML iconHTML  

    We investigate the properties of an electrostatically driven microcantilever exhibiting duffing-like behavior using harmonic detection of resonance. Its potential use as a highly sensitive sensing platform is discussed. We find high sensitivity of this duffing system near its bistability point in a gaseous environment. The response of the higher harmonics of the measured charge on the cantilever induced by an ac voltage that drives the counter electrode is investigated. In particular, we follow the duffing behavior at the higher harmonics (up to the sixth harmonic) as a function of gap distance between the cantilever and counter electrode. To our knowledge, this work represents the first experimental demonstration of sensing a pressure change using the duffing behavior. View full abstract»

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  • Development of a High-k Pr _{2} O _{3} Sensing Membrane for pH-ISFET Application

    Publication Year: 2008 , Page(s): 1856 - 1861
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (573 KB) |  | HTML iconHTML  

    In order to develop a pH sensor having a good pH-sensing characteristic, electrolyte-insulator-semiconductor capacitors using a high-k P2O3 thin film as the sensing membrane were fabricated on silicon substrates by reactive radio frequency sputtering. The structural and morphological features of these films with annealing at various temperatures were studied by X-ray diffraction, atomic force microscopy, and X-ray photoelectron spectroscopy. The Pr2O3 sensing film after annealing at 900degC is suggested to the increase in the interfacial SiO2 and silicate formation, and the high surface roughness. Therefore, a physical vapor deposition Pr2O3 film is adopted as a new pH-sensing layer. The result produces a pH response of 52.9 mV/pH (pH=2-12), a hysteresis voltage of 17.5 mV (pH=7 rarr 4 rarr 7rarr 10 rarr 7), and a drift rate of 2.15 mV/h (pH=7 buffer solution). View full abstract»

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  • Reducing Readout Complexity of Large Resistive Sensor Arrays

    Publication Year: 2008 , Page(s): 1862 - 1863
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (130 KB) |  | HTML iconHTML  

    In this paper, we present a method that simplifies the interconnect complexity of {\rm N} \times {\rm M} resistive arrays from {\rm N} \times {\rm M} to {\rm N} + {\rm M} . In this method, we propose to use two sets of metal lines in row-column fashion with all the sensor elements having one of their ends connected to a row line and other end to a column line. The crosstalk among all the elements introduced due to this connection scheme causes the spreading of information over the whole area of the array. We have proposed and implemented the circuit to eliminate this crosstalk and to get automated sequential access of all the individual elements. The method has been verified using lock-in-amplifier based measurements on the light dependent resistors (LDR) in different array formats. View full abstract»

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  • Low-Noise Signal Processing Chain for High Capacitance Sensors

    Publication Year: 2008 , Page(s): 1864 - 1870
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (855 KB) |  | HTML iconHTML  

    A low-noise readout array is proposed for use with high capacitance detectors. The readout array is composed of a preamplifier/amplifier chain. The signal processing chain is designed for use with CdZnTe gamma ray detectors employed by NASA for radiation detection. This approach employs correlated double sampling and capacitive matching to increase the signal-to-noise ratio (SNR). The readout array is custom designed to fit into one detector pixel. The preamplifier/amplifier chain is designed and fabricated in 0.13 mum CMOS8RF IBM technology. The readout array results show that the SNR is significantly improved compared to previous work done in this field. View full abstract»

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  • On Control System Design for the Conventional Mode of Operation of Vibrational Gyroscopes

    Publication Year: 2008 , Page(s): 1871 - 1878
    Cited by:  Papers (10)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (995 KB) |  | HTML iconHTML  

    This paper presents a novel control circuitry design for both vibrating axes (drive and sense) of vibrational gyroscopes, and a new sensing method for time-varying rotation rates. The control design is motivated to address the challenges posed by manufacturing imperfection and environment vibrations that are particularly pronounced in microelectromechanical systems (MEMS) gyroscopes. The method of choice is active disturbance rejection control that, unlike most existing control design methods, does not depend on an accurate model of the plant. The task of control design is simplified when the internal dynamics, such as mechanical cross coupling between the drive and sense axes, and external vibrating forces are estimated and cancelled in real time. In both simulation and hardware tests on a vibrational piezoelectric beam gyroscope, the proposed controller proves to be robust against structural uncertainties; it also facilitates accurate sensing of time-varying rotation rates. The results demonstrate a simple, economic, control solution for compensating the manufacturing imperfections and improving sensing performance of the MEMS gyroscopes. View full abstract»

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  • Multiplexed Fiber-Optic Pressure and Temperature Sensor System for Down-Hole Measurement

    Publication Year: 2008 , Page(s): 1879 - 1883
    Cited by:  Papers (12)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (641 KB) |  | HTML iconHTML  

    A fiber Fabry-Perot (F-P) interferometer and a fiber Bragg grating (FBG) based pressure and temperature multiplexing sensor system is presented. This system is designed for high-temperature oil well down-hole permanent monitoring of pressure and temperature. Connecting a FBG temperature sensor and a F-P pressure sensor in series in the sensor head, the sensor system combines the advantages of simple structure of FBG for temperature sensing and high accuracy and low-temperature cross-sensitivity of F-P pressure sensor. Experimental results showed that the temperature measurement accuracy of 0.5degC and the long-term drift of the air gap of the F-P pressure sensor at 300degC is less than 0.1% within 300 h time span. This indicates that a long-term pressure measured accuracy of 0.03 MPa has been achieved in pressure gauge range of 0-30 MPa and in temperature variation range between 18degC to 300degC. View full abstract»

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  • Mitigation of Multipath Fading Effects to Improve Indoor RSSI Performance

    Publication Year: 2008 , Page(s): 1884 - 1886
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (555 KB) |  | HTML iconHTML  

    Received signal strength indicator (RSSI) is not suitable for fine-grained indoor applications because of imprecise and unreliable readings caused by multipath fading. This paper presents a simple and robust mechanism to improve RSSI by mitigating multipath fading effects in an indoor environment. Signal analysis is provided to explain the rationale of this method. The proposed method provides instantaneous solution, thus it is compatible with time-series filters and can be cascaded as additional improvement. The contributions of this proposal are the ease of implementation and its excellent output performance. The results show that it is able to eliminate unwanted noisy components caused by multipath fading, and thus obtain more reliable and stable RSSI readings. View full abstract»

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  • Sensing RF Connector Tightness Using a Grounded Plate Capacitive Structure

    Publication Year: 2008 , Page(s): 1887 - 1893
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (867 KB) |  | HTML iconHTML  

    This paper describes a grounded plate capacitive sensing technique for monitoring mated RF connector tightness. The capacitive sensing structure and conditioning electronics are fabricated on the surface of a small polystyrene disc which is integrated into the RF connector body. A model of the electrostatic-mechanical system accurately predicts the change in capacitance as a function of the torque applied to tighten the mated connectors. Mechanical displacement in the connector (or, indirectly, axial force on the mated connector) translates to a change in the period of an oscillator drive circuit. The sensing system is measured to provide a transducer sensitivity range from 0.15 pF/Nmiddotm at the initial connector mating force to 0.74 pF/Nmiddotm at the high end of mating force. View full abstract»

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  • Sensor for Stiffness Measurements Within the Adult Rat Hippocampus

    Publication Year: 2008 , Page(s): 1894 - 1899
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (764 KB) |  | HTML iconHTML  

    This paper presents a sensitive compliance measurement system for determining the stiffness of the adult rat hippocampus. The device has been successfully fabricated which consists of two strain gauges incorporated in the SU-8 based cantilever. The cantilever-sensor has been fully characterized and its strain sensitivity was found to be approximately 2.5. in vitro testing on the brain tissue has successfully demonstrated that the system is sufficiently sensitive to provide distinctive direct stiffness measurements on various hippocampal regions. View full abstract»

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The IEEE Sensors Journal is a peer-reviewed, monthly online/print  journal devoted to sensors and sensing phenomena

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Editor-in-Chief
Krikor Ozanyan
University of Manchester
Manchester, M13 9PL, U.K.