Academic literature on the topic 'Resonant Mass Sensors'
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Journal articles on the topic "Resonant Mass Sensors"
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Skinner, William S., Sunny Zhang, Robert E. Guldberg, and Keat Ghee Ong. "Magnetoelastic Sensor Optimization for Improving Mass Monitoring." Sensors 22, no. 3 (January 22, 2022): 827. http://dx.doi.org/10.3390/s22030827.
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Magnetoelastic sensors, typically made of magnetostrictive and magnetically-soft materials, can be fabricated from commercially available materials into a variety of shapes and sizes for their intended applications. Since these sensors are wirelessly interrogated via magnetic fields, they are good candidates for use in both research and industry, where detection of environmental parameters in closed and controlled systems is necessary. Common applications for these sensors include the investigation of physical, chemical, and biological parameters based on changes in mass loading at the sensor surface which affect the sensor’s behavior at resonance. To improve the performance of these sensors, optimization of sensor geometry, size, and detection conditions are critical to increasing their mass sensitivity and detectible range. This work focuses on investigating how the geometry of the sensor influences its resonance spectrum, including the sensor’s shape, size, and aspect ratio. In addition to these factors, heterogeneity in resonance magnitude was mapped for the sensor surface and the effect of the magnetic bias field strength on the resonance spectrum was investigated. Analysis of the results indicates that the shape of the sensor has a strong influence on the emergent resonant modes. Reducing the size of the sensor decreased the sensor’s magnitude of resonance. The aspect ratio of the sensor, along with the bias field strength, was also observed to affect the magnitude of the signal; over or under biasing and aspect ratio extremes were observed to decrease the magnitude of resonance, indicating that these parameters can be optimized for a given shape and size of magnetoelastic sensor.
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CHAI, YATING, SUIQIONG LI, SHIN HORIKAWA, MI-KYUNG PARK, VITALY VODYANOY, and BRYAN A. CHIN. "Rapid and Sensitive Detection of Salmonella Typhimurium on Eggshells by Using Wireless Biosensors." Journal of Food Protection 75, no. 4 (April 1, 2012): 631–36. http://dx.doi.org/10.4315/0362-028x.jfp-11-339.
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This article presents rapid, sensitive, direct detection of Salmonella Typhimurium on eggshells by using wireless magnetoelastic (ME) biosensors. The biosensor consists of a freestanding, strip-shaped ME resonator as the signal transducer and the E2 phage as the biomolecular recognition element that selectively binds with Salmonella Typhimurium. This ME biosensor is a type of mass-sensitive biosensor that can be wirelessly actuated into mechanical resonance by an externally applied time-varying magnetic field. When the biosensor binds with Salmonella Typhimurium, the mass of the sensor increases, resulting in a decrease in the sensor's resonant frequency. Multiple E2 phage–coated biosensors (measurement sensors) were placed on eggshells spiked with Salmonella Typhimurium of various concentrations (1.6 to 1.6 × 107 CFU/cm2). Control sensors without phage were also used to compensate for environmental effects and nonspecific binding. After 20 min in a humidity-controlled chamber (95%) to allow binding of the bacteria to the sensors to occur, the resonant frequency of the sensors was wirelessly measured and compared with their initial resonant frequency. The resonant frequency change of the measurement sensors was found to be statistically different from that of the control sensors down to 1.6 × 102 CFU/cm2, the detection limit for this work. In addition, scanning electron microscopy imaging verified that the measured resonant frequency changes were directly related to the number of bound cells on the sensor surface. The total assay time of the presented methodology was approximately 30 min, facilitating rapid detection of Salmonella Typhimurium without any preceding sampling procedures.
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Han, Jian Qiang, Xiao Fei Wang, and Ri Sheng Feng. "Dependence of the Resonance Frequency of Mircobridge Resonators on the Thermal Power and Vacuum." Advanced Materials Research 465 (February 2012): 14–22. http://dx.doi.org/10.4028/www.scientific.net/amr.465.14.
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Microbridge resonators have been widely used as sensing elements to measure various parameters, such as pressure, acceleration, biochemical adsorption and reactions, mass-flow, infrared ray et al. But no model has been built to calculate quantitatively the shift of resonance frequency due to heat convection, incident infrared ray, excited thermal power drift and ambient air pressure. In this paper, a theoretical analysis is given to calculate the resonance frequency shift due to the thermal power (static heating power and dynamic heating power) fluctuation and the added mass of the ambient air. The model can be used to design resonant sensors based on microbridge resonator, such as resonant mass-flow sensors, resonant IR detectors, resonant biochemical sensors and resonant vacuum gauge, et al.
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Ge, Chang, and Edmond Cretu. "Simple and Robust Microfabrication of Polymeric Piezoelectric Resonating MEMS Mass Sensors." Sensors 22, no. 8 (April 13, 2022): 2994. http://dx.doi.org/10.3390/s22082994.
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Resonating MEMS mass sensors are microdevices with broad applications in fields such as bioscience and biochemistry. Their advantageous surface-to-volume ratio makes their resonant frequency highly sensitive to variations in their mass induced by surface depositions. Recent global challenges, such as water quality monitoring or pandemic containment, have increased the need for low-cost (even disposable), rapidly fabricated microdevices as suitable detectors. Resonant MEMS mass sensors are among the best candidates. This paper introduces a simple and robust fabrication of polymeric piezoelectric resonating MEMS mass sensors. The microfabrication technology replaces the traditional layer-by-layer micromachining techniques with laser micromachining to gain extra simplicity. Membrane-based resonant sensors have been fabricated to test the technology. Their characterization results have proven that the technology is robust with good reproducibility (around 2% batch level variations in the resonant frequency). Initial tests for the MEMS mass sensors’ sensitivity have indicated a sensitivity of 340 Hz/ng. The concept could be a starting point for developing low-cost MEMS sensing solutions for pandemic control, health examination, and pollution monitoring.
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Siddaiah, Nalluri, D. V. Rama Koti Reddy, Y. Bhavani Sankar, R. Anil Kumar, and Hossein Pakdast. "Modeling and Simulation of Triple Coupled Cantilever Sensor for Mass Sensing Applications." International Journal of Electrical and Computer Engineering (IJECE) 5, no. 3 (June 1, 2015): 403. http://dx.doi.org/10.11591/ijece.v5i3.pp403-408.
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Cantilever sensors have been the growing attention in last decades and their use as a mass detector. This work presents design, modeling and analysis of Triple coupled cantilever(TCC) sensor using MEMS simulation software Comsol Multiphysics with critical dimensions of 100μm length,20μm width and 2μm thickness. Simulations were performed based on finite element modeling techniques, where different resonant frequencies were observed for different modes of operation. It is also observed that the resonant frequency of the sensor decreases as some mass is applied on one particular cantilever. The various parameters greatly affecting the performance of TCC such as resonant frequency, dimensions, material and pressure or force applied on it.we also observed that while adding some mass on any one lateral cantilever, the resonant frequency of that respective mode reduced.
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Körner, Julia, Christopher F. Reiche, Bernd Büchner, and Thomas Mühl. "Theory and application of a novel co-resonant cantilever sensor." tm - Technisches Messen 85, no. 6 (June 1, 2018): 410–19. http://dx.doi.org/10.1515/teme-2017-0139.
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Abstract Dynamic cantilever sensors have many applications, for example in material’s research, biology, as gas and magnetic field sensors. The sensing principle is based on the effect that a force gradient or mass change applied to the cantilever alter its oscillatory state which can be related to the parameter of interest. In order to detect very small interactions, the cantilever needs to have a low stiffness which is commonly achieved by a reduction of the beam’s dimensions, especially its thickness. However, this is limited by the commonly employed laser-based detection of the cantilever’s oscillatory state. In this paper, we describe a novel co-resonant cantilever sensor concept which is based on the coupling and eigenfrequency matching of a micro- and a nanocantilever. This approach allows to access a large fraction of the nanocantilever’s high sensitivity while ensuring a reliable oscillation detection with standard laser-based methods at the microcantilever. Experiments in cantilever magnetometry and magnetic force microscopy demonstrate the immense potential of the sensor concept. Furthermore, applications are not limited to material’s research, instead this concept creates a cantilever sensor platform with many potential applications, for example as gas, mass or pressure sensors.
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Li, Lei, Yin-ping Zhang, Chi-cheng Ma, Can-chang Liu, and Bo Peng. "Anti-Symmetric Mode Vibration of Electrostatically Actuated Clamped–Clamped Microbeams for Mass Sensing." Micromachines 11, no. 1 (December 19, 2019): 12. http://dx.doi.org/10.3390/mi11010012.
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This paper details study of the anti-symmetric response to the symmetrical electrostatic excitation of a Micro-electro-mechanical-systems (MEMS) resonant mass sensor. Under higher order mode excitation, two nonlinear coupled flexural modes to describe MEMS mass sensors are obtained by using Hamilton’s principle and Galerkin method. Static analysis is introduced to investigate the effect of added mass on the natural frequency of the resonant sensor. Then, the perturbation method is applied to determine the response and stability of the system for small amplitude vibration. Through bifurcation analysis, the physical conditions of the anti-symmetric mode vibration are obtained. The corresponding stability analysis is carried out. Results show that the added mass can change the bifurcation behaviors of the anti-symmetric mode and affect the voltage and frequency of the bifurcation jump point. Typically, we propose a mass parameter identification method based on the dynamic jump motion of the anti-symmetric mode. Numerical studies are introduced to verify the validity of mass detection method. Finally, the influence of physical parameters on the sensitivity of mass sensor is analyzed. It is found that the DC voltage and mass adsorption position are critical to the sensitivity of the sensor. The results of this paper can be potentially useful in nonlinear mass sensors.
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Jia, Hao, Pengcheng Xu, and Xinxin Li. "Integrated Resonant Micro/Nano Gravimetric Sensors for Bio/Chemical Detection in Air and Liquid." Micromachines 12, no. 6 (May 31, 2021): 645. http://dx.doi.org/10.3390/mi12060645.
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Resonant micro/nanoelectromechanical systems (MEMS/NEMS) with on-chip integrated excitation and readout components, exhibit exquisite gravimetric sensitivities which have greatly advanced the bio/chemical sensor technologies in the past two decades. This paper reviews the development of integrated MEMS/NEMS resonators for bio/chemical sensing applications mainly in air and liquid. Different vibrational modes (bending, torsional, in-plane, and extensional modes) have been exploited to enhance the quality (Q) factors and mass sensing performance in viscous media. Such resonant mass sensors have shown great potential in detecting many kinds of trace analytes in gas and liquid phases, such as chemical vapors, volatile organic compounds, pollutant gases, bacteria, biomarkers, and DNA. The integrated MEMS/NEMS mass sensors will continuously push the detection limit of trace bio/chemical molecules and bring a better understanding of gas/nanomaterial interaction and molecular binding mechanisms.
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Naeli, Kianoush, and Oliver Brand. "Cancellation of environmental effects in resonant mass sensors based on resonance mode and effective mass." Review of Scientific Instruments 80, no. 6 (June 2009): 063903. http://dx.doi.org/10.1063/1.3143567.
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Körner, Julia. "Effective sensor properties and sensitivity considerations of a dynamic co-resonantly coupled cantilever sensor." Beilstein Journal of Nanotechnology 9 (September 25, 2018): 2546–60. http://dx.doi.org/10.3762/bjnano.9.237.
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Background: Co-resonant coupling of a micro- and a nanocantilever can be introduced to significantly enhance the sensitivity of dynamic-mode cantilever sensors while maintaining the ease of detection. Experimentally, a low-stiffness nanocantilever is coupled to an easy to read out microcantilever and the eigenfrequencies of both beams are brought close to one another. This results in a strong interplay between both beams and, hence, any interaction applied at the nanocantilever alters the oscillatory state of the coupled system as a whole and can be detected at the microcantilever. The amplitude response curve of the microcantilever exhibits two resonance peaks and their response to an interaction applied to the sensor depends on the properties of the individual beams and the degree of frequency matching. Consequently, while an individual cantilever is characterized by its eigenfrequency, spring constant, effective mass and quality factor, the resonance peaks of the co-resonantly coupled system can be described by effective properties which are a mixture of both subsystem’s characteristics. These effective properties give insight into the amount of sensitivity of the nanocantilever that can be accessed and, consequently, into the sensitivity gain associated with the co-resonance. In order to design sensors based on the co-resonant principle and predict their behaviour it is crucial to derive a description for these effective sensor properties. Results: By modeling the co-resonantly coupled system as a coupled harmonic oscillator and using electromechanical analogies, analytical expressions for the effective sensor properties have been derived and discussed. To illustrate the findings, numerical values for an exemplary system based on experimental sensor realizations have been employed. The results give insight into the complex interplay between the individual subsystem’s properties and the frequency matching, leading to a rather large parameter space for the co-resonant system’s effective properties. While the effective spring constant and effective mass mainly define the sensitivity of the coupled cantilever sensor, the effective quality factor primarily influences the detectability. Hence, a balance has to be found in optimizing both parameters in sensor design which becomes possible with the derived analytic expressions. Besides the description of effective sensor properties, it was studied how the thermal noise and, consequently, minimal detectable frequency shift for the co-resonantly coupled sensor represented by a coupled harmonic oscillator could be derived. Due to the complex nature of the coupled system’s transfer function and the required analysis, it is beyond the scope of this publication to present a full solution. Instead, a simplified approach to estimate the minimal detectable frequency shift for the co-resonant system based on the effective sensor properties is given. Conclusion: By establishing a theoretical description for the effective sensor properties of a co-resonantly coupled system, the design of such systems is facilitated as sensor parameters can easily be predicted and adapted for a desired use case. It allows to study the potential sensitivity (gain) and detectability capabilities before sensor fabrication in a fast and easy way, even for large parameter spaces. So far, such an analysis of a co-resonantly coupled sensor was only possible with numerical methods and even then only with very limited capability to include and understand the complex interplay between all contributions. The outlined calculation steps regarding the noise considerations in a coupled harmonic oscillator system can provide the basis for a thorough study of that question. Furthermore, in a broader scope, the investigations presented within this work contribute towards extending and completing the already established theoretical basics of this novel co-resonant sensor concept and open up new ways of studying the coupled system’s behaviour.
Dissertations / Theses on the topic "Resonant Mass Sensors"
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Arab, Hassani Faezeh. "Resonant nano-electro-mechanical sensors for molecular mass-detection." Thesis, University of Southampton, 2012. https://eprints.soton.ac.uk/336335/.
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This research is conducted as a part of EU FP7 project entitled NEMSIC (hybrid nanoelectro-mechanical/integrated circuit systems for sensing and power management applications) with project partners, EPFL, TU Delft, IMEC-NL, CEA-LETI, SCIPROM, IMEC-BE, Honeywell Romania, and HiQSCREEN. Nano-electro-mechanical (NEM) sensors are getting an increased interest because of their compatibility with “In-IC” integration, low power consumption and high sensitivity to applied force, external damping or additional mass. Today, commercial biosensors are developed based on mass-detection and electro-mechanical principles. One of the recent commercial mass-detection biosensors is a quartz crystal microbalance (QCM) biosensor which achieves the mass sensitivity of a few tens pico g/Hz. The newly developed in-plane resonant NEM (IP R-NEM) sensor in this thesis achieves the mass sensitivity less than zepto g/Hz that is over nine orders smaller than that of the commercial QCM sensor using a much smaller sensing area compared to the QCM sensor. This fact will make the IP-RNEM sensor a world-unique sensor that shows a very high sensitivity to a very small change in mass. The stated mass sensitivity is achieved by modelling the functionalization and detection processes of the suspended beam. For modelling the linker molecules in the functionalization process, a conformal coating layer in different configurations are added to the suspended beam and the sparse distribution of target molecules in the detection process is modeled by changing the density of the coating layer. I would like to clarify that the scaling rule of the mass responsivity is given by k4 regardless of the different functionalization configurations. I develop a completely new hybrid NEM-MOS simulation technology which combines three-dimensional finite element method (3D FEM) based NEM device-level simulation and circuit-level simulation for NEM-MOS hybrid circuits. The FEM device-level simulation module also includes new modelling of selfassembled monolayer for surface functionalization as well as adsorb ed molecules to be detected and facilitates quantitative evaluation of mass responsivity of designed NEM sensor devices. The basic part of the sensor, the NEM structure, includes a suspended beam and two side electrodes and that is fabricated at the Southampton Nanofabrication Centre (SNC). The fabrication at SNC includes a new sensor that uses a free-free beam that improves the quality factor up to five orders of magnitude at room temperature and atmosphere based on the numerical results. The IP R-NEM sensor consists of a suspended beam that is integrated with an in-plane MOSFET and is fabricated by CEA-LETI. The monolithically integrated NEM with the MOSFET on the same SOI layer for the sensor is a real breakthrough which makes it a potential low-cost candidate among the mass-detection based sensors. With respect to the conducted radio-frequency (RF) characterization for nano-wire devices in collaboration with the Tokyo Institute of Technology and NEM structures, the designing of an RF contact pad to reduce the effect of parasitic frequencies and doing the measurement at high vacuum to reduce the motional resistance and increase the quality factor are necessary for the characterization of devices with nano-scale dimensions. The integrated MOSFET in the IP RNEM sensor amplifies the output transmission signal from the resonating beam by its intrinsic gain. The fabricated sensors show a three orders of magnitude larger gain than that of the previously proposed resonant suspended gate FETs by biasing the MOSFET at the optimized voltage biases that are found based on the DC characterization of MOSFETs.
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Byun, Albert Joonsoo. "Chemical Application of Silicon-Based Resonant Microsensor." Thesis, Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/16296.
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The detection of volatile organic compounds in liquid is of interest for applications in public health, workplace safety and environmental monitoring. Traditionally, water samples were taken and analyzed in the laboratory using classical laboratory instrumentation. Current trends target real-time measurements using e.g. chemical microsensors built with microfabrication technologies. Among these, mass-sensitive chemical sensors, based on cantilever beams or surface acoustic devices, have shown substantial promise in gas-phase applications. In a liquid environment, the resonant microstructures typically suffer from high damping, which negatively affects the sensor resolution. In this work, a novel disk-type resonator developed at Georgia Tech was investigated as chemical microsensor for liquid-phase applications. The micromachined resonator vibrates in a rotational in-plane mode shape, reducing damping in a liquid environment. As part of the present research, a measurement setup with a custom-made flow cell for liquid-phase chemical measurements and a coating system to locally deposit polymer sensitive films onto the resonators were developed. To improve the film adhesion on the resonator surface in liquid, physical and chemical binding techniques were developed and tested on wafer samples. Polymers such as poly(4-vinylpyrrolidone), poly(ethylene-co-propylene) and poly(styrene-co-butadiene) were deposited using the custom-designed coating system onto the disk-type resonators. Liquid-phase measurements using tetrachloroethylene as the chemical analyte were performed. The experimental results are discussed, sources of problems are identified and recommendations for future research are made.
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Dobson, Mark Geoff. "Development of a MEMS resonant mass sensor for mRNA measurement." Thesis, University of Newcastle Upon Tyne, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.407870.
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Eroglu, Deniz. "Development Of A Resonant Mass Sensor For Mems Based Cell Detection Applications." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614792/index.pdf.
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This thesis reports design and implementation of a MEMS based resonant mass sensor for cell detection applications. The main objective of the thesis is the real-time detection of captured cells inside liquid medium and obtaining the detection results by electronic means, without the aid of any external optical instruments.
A new resonant mass sensor architecture is presented that has various advantages over its conventional counterparts. The device oscillates in the lateral direction, eliminating squeeze film damping. A thin parylene layer coated on the device prevents liquids from entering the narrow gaps of the device, further improving the quality factor. The resonator is embedded on the floor of a microchannel. A gold film on the proof mass facilitates antibody based cell capture on the device.
Theoretical background regarding resonator operation is investigated. Various resonator designs are presented, taking into account design trade-offs, application
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considerations, and fabrication limitations. The design procedure is verified with MATLAB Simulink modeling results and finite element simulations.
A new process flow has been developed for resonator fabrication, combining SOI, glass, and polymer micromachining. Modifications have been done on the flow for the solution of problems encountered during device fabrication. Each device has a foot print area of 1.5 x 0.5 cm2. The majority of this area is occupied by fluidic connections and reservoirs.
Resonance characterization results in air and water have shown that there is significant quality factor enhancement with the parylene coating method. The quality factor decreases to only 170 in water from 610 in air, when the resonator is coated with a thin layer of parylene. Uniformity and linearity tests revealed that the devices have a standard deviation of only 1.9% for different analyte capture sites and an R2 of 0.997 for mass loads as high as 2.7 ng.
Detection of Saccharomyces cerevisiae type yeast cells has been done using the resonators. Mass measurement of single yeast cell (13 pg) and yeast clusters (102 pg) have been performed. Antibody and thiol-gold chemistry based Candida Albicans type bacteria capture and detection has also been made in both air and water environments. The mass of several captured bacterial cells in air has been measured as 95pg. Two bacterial cells have been captured on one device inside water and their mass has been measured as 85 pg. It is worthy to note that all mass measurements are consistent with theoretical expectations.
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Demirci, Kemal Safak. "Chemical microsystem based on integration of resonant microsensor and CMOS ASIC." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/41182.
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The main topic of this thesis is the development of a chemical microsystem based on integration of a silicon-based resonant microsensor and a CMOS ASIC for portable sensing applications. Cantilever and disk-shape microresonators have been used as mass-sensitive sensors. Based on the characteristics of the microresonators, CMOS integrated interface and control electronics have been implemented. The CMOS ASIC utilizes the self-oscillation method, which incorporates the microresonator in an amplifying feedback loop as the frequency determining element. In this manner, the ASIC includes a main feedback loop to sustain oscillation at or close to the fundamental resonance frequency of the microresonator. For stable oscillation, an automatic gain control loop regulates the oscillation amplitude by controlling the gain of the main feedback loop. In addition, an automatic phase control loop has been included to adjust the phase of the main feedback loop to ensure an operating point as close as possible to the resonance frequency, resulting in improved frequency stability. The CMOS chip has been interfaced to cantilever and disk-shape microresonators and short-term frequency stabilities as low as 3.4×10-8 in air have been obtained with a 1 sec gate time.
The performance of the implemented microsystem as a chemical sensor has been evaluated experimentally with microresonators coated with chemically sensitive polymer films. With a gas-phase chemical measurement setup constructed in this work, chemical measurements have been performed and different concentrations of VOCs, such as benzene, toluene and m-xylene have been detected with limits of detection of 5.3 ppm, 1.2 ppm and 0.35 ppm, respectively.
To improve the long-term stability in monitoring applications with slowly changing analyte signatures, a method to compensate for frequency drift caused by environmental disturbances has been implemented on the CMOS chip. This method uses a controlled stiffness modulation generated by a frequency drift compensation circuit to track the changes in the resonator's Q-factor in response to variations in the environmental conditions. The measured Q-factor is then used to compensate for the frequency drift using an initial calibration step. The feasibility of the proposed method has been verified experimentally by compensating for temperature-induced frequency drift during gas-phase chemical measurements.
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Grahmann, Jan. "Hochempfindliche resonante Gassensoren auf der Basis von einkristallinen Silizium-Plattenschwingern." Doctoral thesis, Universitätsbibliothek Chemnitz, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-201000101.
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Die vorliegende Arbeit beschäftigt sich mit der Modellerstellung und Technologie eines gravimetrischen Gassensors für organische Gase. Die Besonderheit liegt in dem verwendeten Resonatortyp. Es handelt sich um einen lateral elektrostatisch angeregten quadratischen Plattenresonator, der mit einer Rezeptorschicht versehen wird. Mit Hilfe von FEM-Berechnungen werden die Eigenfrequenzen und Eigenformen berechnet. Für die untersuchte Lamé- und Square-Mode wird die Sensorgüte unter Berücksichtigung des "Squeeze-Film-Damping" sowie der viskoelastischen Rezeptorschichteigenschaften bestimmt. Die Sensormoden werden durch ein Feder-Masse-Modell mit einem Freiheitsgrad modelliert und durch ein elektrisches Ersatzschaltbild repräsentiert. Die berechneten Nachweisgrenzen für Oktan und Toluol bei 6-facher Rauschgrenze liegen im zweistelligen ppb-Bereich. Für die technologische Umsetzung werden SOI-Wafer verwendet. Die ≤ 100 nm betragenden Spaltbreiten zwischen Elektroden und Resonator werden durch das RIE-Ätzen von Siliziumgräben mit senkrechten Seitenwänden, der Abscheidung von SiO2 als Opferschicht und dem Füllen der Gräben mit hochdotiertem Polysilizium hergestellt. Die Kontaktierung der Resonatoren erfolgt über einen leitenden Stamm, der aufgrund von selbstjustierenden Prozessen die Resonatorplatte zentriert einspanntThe following work is concerned with the modelling and fabrication technology of a gravimetric sensor for volatile organic compounds (VOC). Novelty is the combination of a lateral electrostatic driven square plate resonator with a gas sensitive detection layer. The eigenfrequencies and -modes are calculated with FEM simulations. Especially suited for gas sensors are the Lamé- and Square eigenmodes which are studied more closely. The quality factor is determined considering "squeeze film damping" and the viscoelastic properties of the gas sensitive detection layer. To present the sensor oscillation modes a spring mass model with one degree of freedom is determined and extended by an equivalent circuit diagram. The calculated limits of detections for octane and toluene are in the binary ppb-range, working with six times the limit of frequency noise. SOI-wafers are the base material for the sensor process flow. Electrode gaps ≤100 nm, essential for the electrostatic drive, are fabricated by RIE-etching vertical trenches into the device layer down to the buried oxide and by depositing a silicon dioxide as sacrifical layer and by refilling the trenches with highly doped polysilicon. The electrical contact of the resonator plate is ensured through an electrical conducting polysilicon stem. The developed process flow enables a self alignment ot the stem, clamping the plate centered
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Polapragada, Hara Krishna. "Study Of The Effect Of Elasticity Of The Added Mass In Mass Sensing Using Resonant Peak Shift Technique." Thesis, 2009. http://etd.iisc.ernet.in/handle/2005/1997.
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Micromachined biosensors are used in chemical and biological applications. A biosensor which uses mass based transduction is called a mass sensor. Mass sensors are used to detect extremely small mass of biomolecules such as proteins, viruses or even parts of DNA in the range of femtograms (10-15 gm) to zeptograms (10−21 gm). Highly effective and reliable microcantilevers are used for detecting the mass of biomolecules using either static deflection or dynamic resonant peak shifts. The main objective of our work is to investigate the effect of elasticity of the attached mass on the shift in the resonant frequency and examine the validity of the rigid mass assumption used in the literature.
The natural frequencies of a resonator are either found by solving the governing differential equation or approximately using Rayleigh-Ritz method. The mass of a body, attached to a resonator beam is determined using resonant frequency shift method. In our study, we derive an analytical expression for ‘δm’ based on the shift in frequency ‘δf’ that accounts for the elasticity of the added mass and the location of the mass on the beam. We study the simplest model to incorporate these effects where the added mass is itself modeled as a single degree of freedom spring-mass system. The entire system is represented as a 2-DOF lumped model of cantilever and the attached elastic mass. The natural frequencies are obtained using eigenvalue analysis. We study the mass estimation of Escherichia Coli (E. Coli), a food borne pathogen, using experimental results reported in the literature. We treat E.Coli as an elastic mass and model it as a single degree of freedom system to account for its elasticity. We use the elastic model as well as the rigid mass model to check the results available in the literature and point out the difference that results in mass estimation using the two models.
To demonstrate the effect of elasticity on mass sensing using the resonant peak shift technique, we conduct mesoscale experiments. Since the fundamental principle does not depend on any phenomenon exclusively dependent on micro scales, the mesoscale experiments are justified. For this purpose, an experimental set-up with metallic cantilevers and flexible rubber strands as attached masses are used. We also use our experimental set-up to study the effect of positional inaccuracy of the added mass (rigid) in the computation of its mass from the shift in the resonance frequency. The results obtained show that elasticity of the added mass as well as its position on the resonator affect the computed mass but this effect is dependent on the relative stiffness and mass of the resonator and the added mass. We also observe the limitations of the experiments in carrying out studies over the desired range of parameters. We also create a computational model of the system and carry out simulations to explore a larger range of parameter values. In particular, we create an FEM model of our system in ANSYS, and carry out modal analysis for the cantilever beam resonator with and without the added mass, varying the relative stiffness and mass of the two components (the cantilever beam and the added mass). We compare the results of shift in the resonant frequency with those obtained from the rigid mass model. The results show the effect of elasticity clearly in certain ranges of relative stiffness and mass.
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Shrikanth, V. "A Non Resonant Piezoelectric Sensor for Mass, Force and Stiffness Measurements." Thesis, 2015. http://etd.iisc.ernet.in/2005/4000.
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The word piezo in greek means \to compress". Piezoelectric sensors work on the principle of direct piezoelectric effect, where a mechanical input generates a corresponding electric charge. The advantages of these sensors are wide fre-quency range of operation, high stiffness and small size. The main limitation of a piezoelectric sensor is that it cannot be used in measurements that are truly static. When a piezoelectric sensor is subjected to a static force, a fixed amount of charge is developed which would eventually decay at a rate dependent on the external impedance of the sensor circuitry. Operating sensors at resonance have been one of the methods to overcome the limitation of using piezoelectric sensors for static measurements. However, since both actuation and sensing are done by the same piezoelectric element, this results in a cross-talk of input and output signals.
The drawback of using single piezoelectric element for actuation and sensing is overcome in this work by using two identical elements|one for actuation and one for sensing. The operating frequency is about 10 % of the natural frequency of the sensor, thus enabling to operate the sensor in non resonant mode. Since the actuation and sensing mechanisms are separated, static measurement can be carried out. The output signal from the sensing element is monitored by a Lock-in amplifier which works on the principle of phase sensitive detection. The advantage of this sensor design is high sensitivity along with narrow band detection. It can be shown that the voltage output of the sensor Vout / a1 + m(b1 + b2F + b3K) + c1F + d1K, where m and K are the external mass and interaction stiffness, respectively, F is the force acting on it. By maintaining any two of these three quantities constant, the remaining one can be measured without any difficulty. The non resonant mode of operation makes it possible to explore the potential of this sensor in investigating mechanics of solid-liquid (viscous), solid-solid (inelastic) and solid-tissue(viscoelastic) interactions.
High sensitivity, wide range of measurement (1 g{1 g) and high resolutio(0.1 g) of the non resonant mass sensor makes it possible to use it in measure-ment of very small masses of the order 1 g. Typically, resonant sensors such as quartz crystal microbalance (QCM) are used for mass measurements at that range. However, since the performance of resonant sensors is controlled by damp-ing, a phenomenon known as `missing mass effect' arises. Operating a sensor in non resonant mode (stiffness controlled mode) is a way to overcome this problem, especially when the mass is viscous and/or viscoelastic in nature. Drosophila fly, egg and larvae are the viscoelastic masses that are measured using this non res-onant sensor. Evaporating sessile drops of water and Cetyl trimethylammonium bromide (CTAB) surfactant solution from nominally flat surfaces are monitored to characterize the sensor for viscous mass measurement. Evaporation rate per unit surface area remains more or less constant, during the initial stages of evap-oration. When the surfactant concentration is varied, evaporation rate per unit surface area is highest for solutions around critical miscelle concentration (CMC). A study is carried out to understand the effect of concentrations on spreading of ink over inkjet printing paper. It is found that the spreading is least around CMC, since spreading is dependent on the rate of evaporation.
The non resonant piezoelectric sensor which has high stiffness and quick re-sponse is also capable of measuring very small frictional forces. This sensor is configured to work as an inertial slider. Friction measurement at micro scales is important for designing microsystems such as stick-slip actuators. At such length scales, experiments have to performed at low loads and high excitation frequencies. The support stiffness of such systems should be high and the force of friction generated during slipping, when displacements are smaller than the contact radius, are of the order of few N. The displacement during slipping (S) is dependent on the amplitude of the input voltage to the actuation element. The frictional force measured during slipping by the sensor element indicates that the co-efficient of friction ( ) is independent of the sliding velocity.
The developed non resonant sensor in this work under small amplitude exci-tation, can measure force gradient (i.e. stiffness). The total force generated when a needle is inserted into a viscoelastic material is a sum of force due to stiffness of the material, friction and the cutting force at the tip. The force due to stiffness is dominant when the needle is bending the tissue before the puncture occurs. Use of the non resonant sensor in tandem with strain gauge force sensor enables distinguishing the three components of the total force. The slope of the force-displacement (F -d) curve during the initial stages of needle penetration into the viscoelastic material, before puncture, is indicative of the stiffness of the mate-rial. The peak force measured during penetration is higher for needles with larger diameters and lower insertion velocities. The viscoelastic response (relaxation) of the material remains independent of the insertion velocity, for a given thickness of the material and a constant needle diameter.
In summary, the sensor designed and developed in this work operates in stiffness controlled mode to eliminate the `missing mass effect' encountered dur-ing resonant mode of operation, has been clearly highlighted. Mass, force and stiffness measurements are possible over a wide range just by varying the ampli-tude of the input signal to the actuator element. The advantages such as high stiffness, small size and high response makes it advantageous to carry out in-situ micro scale studies in scanning electron microscopy (SEM) and transmission electron microscopy (TEM).
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(7845965), Allison K. Murray. "EXPLORING THE INKJET PRINTING OF FUNCTIONAL MATERIALS AND THEIR USE IN ENERGETIC SYSTEMS AND SENSING APPLICATIONS." Thesis, 2019.
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With an eye towards applications such as the selective sensing of volatile organic compounds (VOCs) or micro-scale thrust generation, inkjet printing was explored as a means to selectively deposit functional materials. The work detailed herein explores a series of fundamental steps to gain expertise related to the piezoelectric inkjet printing of functional materials. The successful printing of nanothermite was demonstrated with two unique printing techniques. Furthermore, the integration of this material with an ignition mechanism was shown to create a fully printed igniter energetic system. These advancements support future work related to the printing of other energetic materials necessary to create tunable reactive systems. This knowledge was then translated into the development of resonant mass sensing devices that are selectively functionalized using inkjet printing. This approach to functionalization allowed for the precise deposition of receptive chemistries on devices resulting in selective, highly-sensitive devices that successfully detected biomarkers secreted after traumatic brain injuries and harmful VOCs. This work implemented oscillator-based sensors to achieve a low-cost, low-power sensor platform with redundant elements. Furthermore, the predictive capabilities of these devices were explored using least squares and linear regression modeling.
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(9759650), Conor S. Pyles. "The Dynamics of Coupled Resonant Systems and Their Applications in Sensing." Thesis, 2020.
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The field of coupled resonant systems is a rich research area with enumerable real-world applications, including the fields of neural computing and pattern recognition, energy harvesting, and even modeling the behavior of certain types of biological systems. This work is primarily focused on the study of the behaviors of two subsets of this field: large networks of globally coupled resonators (which, in this work, refers to passive, damped resonant elements which require external stimulus) and smaller networks of oscillators (referring to active devices capable of self-sustained motion), which are coupled through a network of light-sensitive resistive elements. In the case of the former, we begin by developing an analytical and experimental framework to examine the behaviors of this system under various conditions, such as different coupling modalities and element-level parametric mistunings. Once a proper understanding of the dynamics of these systems has been established, we go on to develop the system into a single-input, single-output, multi-analyte volatile organic compound sensor. For the study of oscillator networks, we begin by building a device which utilizes a network of Colpitts oscillators, coupled through a series of color-filtered CdSe photocells. We then establish that through the analysis of particular emergent behaviors (most notably, frequency locking within the network), this type of system may show promise as a threshold color sensor. By exploiting these behaviors, this type of system may find applications in neuromorphic computing (particularly in optical pattern recognition).
Book chapters on the topic "Resonant Mass Sensors"
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Yoda, Minami, Jean-Luc Garden, Olivier Bourgeois, Aeraj Haque, Aloke Kumar, Hans Deyhle, Simone Hieber, et al. "NEMS Resonant Mass Sensors." In Encyclopedia of Nanotechnology, 1895. Dordrecht: Springer Netherlands, 2012. http://dx.doi.org/10.1007/978-90-481-9751-4_100591.
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"NEMS Resonant Mass Sensors." In Encyclopedia of Nanotechnology, 2941. Dordrecht: Springer Netherlands, 2016. http://dx.doi.org/10.1007/978-94-017-9780-1_100801.
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Alfaifi, Ahmad, Adnan Zaman, and Abdulrahman Alsolami. "MEMS Humidity Sensors." In Humidity Sensors [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.98361.
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This chapter reviews MEMS humidity sensors fabricated using microfabrication technologies. It discusses the operation principle, different designs, and the fabrication technologies for the different sensing mechanisms. Sensing humidity using capacitive sensors is first reviewed with a highlight on the different sensing materials and how their permittivity and physical parameters affect the sensor performance. Then the chapter discusses the piezoelectric humidity sensing method, wherein piezoelectric sensors the dynamic mode measurement is used. In these sensors, the mass changes corresponding to the humidity, resulting in resonance frequency shift and amplitude change. Finally, the chapter reviews the resistive humidity sensors where the change in the resistivity of various materials is used as an indication of humidity change in the environment.
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Joshi, Anand Y., and Ajay M. Patel. "Sensing the Presence and Amount of Microbes Using Double Walled Carbon Nanotubes." In Advancing Medicine through Nanotechnology and Nanomechanics Applications, 78–117. IGI Global, 2017. http://dx.doi.org/10.4018/978-1-5225-1043-7.ch004.
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The principle of mass detection using nano biosensors is based on the fact that the resonant frequency is very much sensitive to the mass of the bio-molecule, as with mass changes stiffness varies. The change of the attached mass on the CNT causes a shift to the resonant frequency. The key issue of mass detection is in quantifying the shift in the resonant frequency due to the mass of the attached molecule.This study, explores the vibration responses of the cantilever single and double-walled carbon nanotube with various attached microbes on the tip with an aim of developing a sensor. The biological objects studied include Alanine with Amino terminal residue, Deoxyadeonosine with free residue, Coronaviridae, Bartonella bacilliformis etc.. This sensor will be utilized to facilitate the identification of bacteria or virus that may be attached to CNT.
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Meshginqalam, Bahar, Mohammad Taghi Ahmadi, Hamid Toloue Ajili Tousi, Arash Sabatyan, and Anthony Centeno. "Surface Plasmon Resonance-Based Sensor Modeling." In Handbook of Research on Nanoelectronic Sensor Modeling and Applications, 361–94. IGI Global, 2017. http://dx.doi.org/10.4018/978-1-5225-0736-9.ch014.
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Exceptional optical and electrical characteristics of graphene based materials attract significant interest of the researchers to develop sensing center of surface Plasmon resonance (SPR) based sensors by graphene application. On the other hand refractive index calculation of graphene based structures is necessary for SPR sensor analysis. In this chapter first of all a new method for refractive index investigation of some graphene based structures are introduced and then the effect of carrier density variant in the form of conductance gradient on graphene based SPR sensor response is modeled. The molecular properties such as electro-negativity, molecular mass, effective group number and effective outer shell factor of the molecule are engaged. In addition each factor effect in the cumulative carrier variation is explored analytically. The refractive index shift equation based on these factors is defined and related coefficients are proposed. Finally a semi-empirical model for interpretation of changes in SPR curve is suggested and tested for some organic molecules.
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Patil, Pravin P. "Design and Simulation of Electro-Mechanical Mass Flow Sensor (EMMFS)." In Advanced Numerical Simulations in Mechanical Engineering, 50–62. IGI Global, 2018. http://dx.doi.org/10.4018/978-1-5225-3722-9.ch003.
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The main objective of this chapter is FEA simulation of resonating tube with different size and material configuration for evaluation of resonant frequency. Resonating tube is an important component of Electro-Mechanical Mass Flow Sensor (EMMFS) used for measuring direct mass flow. Omega and U-shaped resonating tube type EMMFS have been investigated for 200mm, 300 mm and 400mm height with three different materials Copper, Aluminium and Mild Steel. EMMFS analysis is highly nonlinear study having fluid structure interaction. To simplify the solution large deformations in resonating tube countered to be absent. Sensing points are located symmetrically at limbs of resonating tube to sense the phase shift for measuring mass flow rate. FEA simulation of EMMFS has been done using Ansys. Solid Edge and Pro-E has been used for modeling of omega and U-shaped resonating tube.
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Carabenciov, Ivan D., and Michael W. Ruff. "Progressive Bilateral Arm Pain, Gait Disturbance, Constipation, and Urinary Retention." In Mayo Clinic Cases in Neuroimmunology, edited by Andrew McKeon, B. Mark Keegan, and W. Oliver Tobin, 231–32. Oxford University Press, 2021. http://dx.doi.org/10.1093/med/9780197583425.003.0075.
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A 48-year-old woman sought care for progressive right arm and hand pain with radial nerve–distribution sensory loss. She had a past history of multiple prior athletics-associated, musculoskeletal, upper cervical spine injuries. Her symptoms were initially attributed to a right C6 radiculopathy. Over the next several months, the sensory loss spread to involve the entire right hand and subsequently the entire left hand. She had development of diffuse right hand weakness and a sense of imbalance that was particularly prominent while in the dark. Finally, she experienced progressive constipation and urinary retention. Magnetic resonance imaging of the cervical spine showed an expanded cervical spinal cord from C3 through C7-T1 with diffuse T2-hyperintense changes and heterogeneous gadolinium enhancement most prominent at C5-6. In combination with a congenitally small central canal, severe central canal narrowing was seen at C5-6 and moderate narrowing at C4-5. Magnetic resonance imaging of the brain and thoracic spine were normal, and magnetic resonance imaging of the lumbar spine indicated only mild lumbar spondylosis. On suspicion of a spinal cord neoplasm with a secondary compressive myelopathy, C3 through C7 laminectomy and posterior instrumented fusion from C2 through T1 was performed, with a biopsy obtained at the C5-6 level. Postoperatively, her gait and right upper extremity pain improved. The biopsy showed atypical glial cells. Neurofilament staining demonstrated an infiltrative pattern. Atypical cells were positive for glial fibrillary acidic protein, oligodendrocyte transcription factor 2, and a Lys27Met sequence variation of histone H3, with overexpression of p53 on immunohistochemical staining. There was loss of H3 K27-trimethylation on the infiltrating cells, corresponding to the presence of Lys27Met sequence variation of histone H3. These findings were diagnostic for diffuse midline glioma with Lys27Met sequence variation of histone H3 (World Health Organization grade IV). A total of 5,400 cGy of photon radiation was delivered in 30 fractions over 42 days. She was subsequently treated with an oral histone deacetylase inhibitor, panobinostat, for 12 months. During this time, she had clinical response to treatment and reported improvement in balance and numbness. Follow-up magnetic resonance imaging at 3 months showed a slight decrease in the size of the mass, and this response was sustained 1 year post radiotherapy. Diffuse midline gliomas that contain Lys27Met sequence variation of histone H3are incurable, often inoperable, midline brain tumors that are most commonly seen in the pediatric population. These tumors can also occur in adult patients and are considered high grade, even in the absence of features such as necrosis or microvascular proliferation.
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Pinto, Fabrizio. "Gravimetry by Nanoscale Parametric Amplifiers Driven by Radiation-Induced Dispersion Force Modulation." In International Association of Geodesy Symposia. Berlin, Heidelberg: Springer Berlin Heidelberg, 2022. http://dx.doi.org/10.1007/1345_2022_179.
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AbstractHere we present early results from lumped-element numerical simulations of a novel class of nano electromechanical systems (NEMS) presently being considered for ground-based gravimetry and future micro accelerometry applications in GPS-denied environments, including spacecraft. The strategy we discuss is based on measuring the effects of non-inertial or gravitational forces on the dynamics of a standard oscillator driven at its resonance frequency by a time-dependent electrostatic potential. In order to substantially enhance the sensitivity of the instrument, the oscillating mass is made to simultaneously interact with a nearby boundary so as to be affected by quantum electrodynamical Casimir forces. Furthermore, unlike previously published proposals, in the design presented herein the Casimir boundary does not oscillate but it is a fixed semiconducting layer. As already demonstrated experimentally, this arrangement enables Casimir force time-modulation by semiconductor back-illumination. Such a design strategy, first suggested by this author as a promising approach to gravitational wave detection in different nano-sensors, allows for the realization of a Casimir force-pumped mechanical parametric amplifier. Such devices can, in principle, yield gains of several orders of magnitude in the mechanical response amplitude over the response from standard unpumped oscillators. The numerical proof-of-concept first presented herein points to a potentially new class of gravimetry products based on exploiting appropriately engineered dispersion forces as an emerging enabling general purpose technology on the nanoscale.
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Sechi, Elia, and Eoin P. Flanagan. "Progressive Quadriparesis and Cancer." In Mayo Clinic Cases in Neuroimmunology, edited by Andrew McKeon, B. Mark Keegan, and W. Oliver Tobin, 122–24. Oxford University Press, 2021. http://dx.doi.org/10.1093/med/9780197583425.003.0039.
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A 67-year-old man with a history of cigarette smoking sought care at the emergency department for nonspecific dizziness and fatigue. During evaluation, chest radiography showed a right upper lobe mass, and he subsequently underwent right upper lobectomy. Histologic analysis of resected tissue showed the mass to be small cell lung carcinoma. Progressive myelopathy developed. Adjuvant chemotherapy with carboplatin and etoposide was begun. His neurologic symptoms continued to worsen, with gait imbalance, along with numbness and dysesthesias of the 4 limbs and trunk, with a sensory level at C3-C4. He also reported severe bowel and bladder dysfunction. At his neurologic nadir, he had severe quadriparesis and was wheelchair dependent. Cerebrospinal fluid analysis showed lymphocytic pleocytosis of 9 lymphocytes/µL, erythrocyte count of 2/µL, and normal protein and glucose values. Serum neural autoantibody screening revealed the presence of collapsin-response mediator protein 5–immunoglobulin G antibodies on both tissue-based indirect immunofluorescence assay and Western blot. The patient was diagnosed with paraneoplastic myelopathy. The patient was initially treated acutely with a combination of high-dose oral prednisone and plasmapheresis, without improvement. Subsequently, a combination of intravenous immunoglobulin and rituximab resulted in partial improvement. Soon after treatment discontinuation, his symptoms returned with worsening weakness, numbness, and neuropathic pain. Monthly intravenous immunoglobulin and rituximab were reinitiated, with improvement again noted. Oral corticosteroids, methadone, and high-dose gabapentin were also administered, with mild benefit for neuropathic pain. Follow-up spine magnetic resonance imaging 3 years after symptom onset showed evidence of spinal cord atrophy. At 5-year follow-up he remained in remission from small cell lung cancer but was wheelchair dependent. Paraneoplastic myelopathy is a rare and underrecognized neurologic disorder that most often manifests before cancer detection, Clinical presentation is generally subacute or slowly progressive over months, but acute onset is possible. Cerebrospinal fluid typically shows lymphocytic pleocytosis, as in this case patient.
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Sechi, Elia, and Dean M. Wingerchuk. "Rapidly Progressive Numbness and Weakness After Soft-Tissue Abscess." In Mayo Clinic Cases in Neuroimmunology, edited by Andrew McKeon, B. Mark Keegan, and W. Oliver Tobin, 7–9. Oxford University Press, 2021. http://dx.doi.org/10.1093/med/9780197583425.003.0002.
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A previously healthy 45-year-old man had development of neck pain and swelling, followed 1 week later by fevers, chills, and night sweats. Cervical computed tomography showed a left-sided cervical soft-tissue abscess. The patient was treated with oral cephalexin for 10 days, without benefit. Fine-needle aspiration biopsy of the mass showed granulomatous inflammation and a heterogeneous lymphocyte population without evidence of malignancy. Meropenem and gentamicin were started. Ten days later, he had development of acute urinary retention, numbness and weakness in the lower extremities, and numbness in the upper extremities. At symptom nadir 2 days later, he required the aid of a walker to ambulate. Lhermitte sign and erectile dysfunction were also present. The patient was admitted to the hospital. Spinal cord magnetic resonance imaging showed a longitudinally extensive, nonenhancing, T2-hyperintense lesion predominantly affecting the ventral and lateral parenchyma of the cervical and thoracic spinal cord. Cerebrospinal fluid examination showed a white blood cell count of 581 cells/µL with 42% neutrophils, 35% lymphocytes, and 22% monocytes, increased protein concentration (109 mg/dL), and normal glucose concentration. A diagnosis of postinfectious idiopathic transverse myelitis was made. The patient was treated with intravenous immunoglobulin, intravenous methylprednisolone, and broad-spectrum antibiotics, with improvement of both the abscess and his neurologic symptoms. After discharge, he was able to walk unassisted. At follow-up evaluation 6 months after the initial evaluation, neurologic examination showed only mild weakness of the left iliopsoas muscle and brisk reflexes in the lower extremities. Acute transverse myelopathies are a heterogeneous group of spinal cord disorders characterized by acute or subacute signs and symptoms of spinal cord dysfunction, typically a combination of sensory, motor, and autonomic manifestations. Underlying causes include vascular, infectious, neoplastic, postirradiation, traumatic, and inherited/metabolic, and inflammatory processes.
Conference papers on the topic "Resonant Mass Sensors"
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Hongyuan Zhao, Wei Pang, and Hao Zhang. "Piezoelectric acoustic resonant mass sensors." In 2010 OSA-IEEE-COS Advances in Optoelectronics and Micro/Nano-Optics (AOM). IEEE, 2010. http://dx.doi.org/10.1109/aom.2010.5713583.
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Bajaj, Nikhil, Jeffrey F. Rhoads, and George T. C. Chiu. "Characterization of Resonant Mass Sensors Using Inkjet Deposition." In ASME 2016 Dynamic Systems and Control Conference. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/dscc2016-9803.
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Micro- and millimeter-scale resonant mass sensors have received widespread research attention due to their robust and highly-sensitive performance in a wide range of detection applications. A key performance metric associated with such systems is the sensitivity of the resonant frequency of a given device to changes in mass, which needs to be calibrated for different sensor designs. This calibration is complicated by the fact that the position of any added mass on a sensor can have an effect on the measured sensitivity, and thus a spatial sensitivity mapping is needed. To date, most approaches for experimental sensitivity characterization are based upon the controlled addition of small masses. These approaches include the direct attachment of microbeads via atomic force microscopy or the selective microelectrodeposition of material, both of which are time consuming and require specialized equipment. This work proposes a method of experimental spatial sensitivity measurement that uses an inkjet system and standard sensor readout methodology to map the spatially-dependent sensitivity of a resonant mass sensor — a significantly easier experimental approach. The methodology is described and demonstrated on a quartz resonator and used to inform practical sensor development.
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Sang-Jin Kim, T. Ono, and M. Esashi. "Mass Detection Using Capacitive Resonant Silicon Sensor." In 2006 5th IEEE Conference on Sensors. IEEE, 2006. http://dx.doi.org/10.1109/icsens.2007.355864.
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Kharrat, Chady, Eric Colinet, and Alina Voda. "H∞ Loop shaping control for PLL-based mechanical resonance tracking in NEMS resonant mass sensors." In 2008 IEEE Sensors. IEEE, 2008. http://dx.doi.org/10.1109/icsens.2008.4716641.
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Park, K., and R. Bashir. "MEMS-based resonant sensor with uniform mass sensitivity." In TRANSDUCERS 2009 - 2009 International Solid-State Sensors, Actuators and Microsystems Conference. IEEE, 2009. http://dx.doi.org/10.1109/sensor.2009.5285673.
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Abdolvand, Reza, Zhili Hao, and Farrokh Ayazi. "A Temperature-Compensated ZnO-on-Diamond Resonant Mass Sensor." In 2006 5th IEEE Conference on Sensors. IEEE, 2006. http://dx.doi.org/10.1109/icsens.2007.355867.
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Heinisch, Martin, Erwin K. Reichel, Bernhard Jakoby, Thomas Voglhuber-Brunnmaier, and Isabelle Dufour. "Investigation of higher mode excitation of resonant mass density and viscosity sensors." In 2014 IEEE Sensors. IEEE, 2014. http://dx.doi.org/10.1109/icsens.2014.6984980.
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Mehdizadeh, Emad, Varun Kumar, Siavash Pourkamali, Jonathan Gonzales, and Reza Abdolvand. "A two-stage aerosol impactor with embedded MEMS resonant mass balances for particulate size segregation and mass concentration monitoring." In 2013 IEEE Sensors. IEEE, 2013. http://dx.doi.org/10.1109/icsens.2013.6688317.
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Hajjam, Arash, Amir Rahafrooz, James C. Wilson, and Siavash Pourkamali. "Thermally actuated MEMS resonant sensors for mass measurement of micro/nanoscale aerosol particles." In 2009 IEEE Sensors. IEEE, 2009. http://dx.doi.org/10.1109/icsens.2009.5398557.
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Wasisto, H. S., S. Merzsch, A. Waag, I. Kirsch, E. Uhde, T. Salthammer, and E. Peiner. "Enhanced airborne nanoparticles mass sensing using a high-mode resonant silicon cantilever sensor." In 2011 IEEE Sensors. IEEE, 2011. http://dx.doi.org/10.1109/icsens.2011.6127053.
Full textReports on the topic "Resonant Mass Sensors"
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Engel, Bernard, Yael Edan, James Simon, Hanoch Pasternak, and Shimon Edelman. Neural Networks for Quality Sorting of Agricultural Produce. United States Department of Agriculture, July 1996. http://dx.doi.org/10.32747/1996.7613033.bard.
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The objectives of this project were to develop procedures and models, based on neural networks, for quality sorting of agricultural produce. Two research teams, one in Purdue University and the other in Israel, coordinated their research efforts on different aspects of each objective utilizing both melons and tomatoes as case studies. At Purdue: An expert system was developed to measure variances in human grading. Data were acquired from eight sensors: vision, two firmness sensors (destructive and nondestructive), chlorophyll from fluorescence, color sensor, electronic sniffer for odor detection, refractometer and a scale (mass). Data were analyzed and provided input for five classification models. Chlorophyll from fluorescence was found to give the best estimation for ripeness stage while the combination of machine vision and firmness from impact performed best for quality sorting. A new algorithm was developed to estimate and minimize training size for supervised classification. A new criteria was established to choose a training set such that a recurrent auto-associative memory neural network is stabilized. Moreover, this method provides for rapid and accurate updating of the classifier over growing seasons, production environments and cultivars. Different classification approaches (parametric and non-parametric) for grading were examined. Statistical methods were found to be as accurate as neural networks in grading. Classification models by voting did not enhance the classification significantly. A hybrid model that incorporated heuristic rules and either a numerical classifier or neural network was found to be superior in classification accuracy with half the required processing of solely the numerical classifier or neural network. In Israel: A multi-sensing approach utilizing non-destructive sensors was developed. Shape, color, stem identification, surface defects and bruises were measured using a color image processing system. Flavor parameters (sugar, acidity, volatiles) and ripeness were measured using a near-infrared system and an electronic sniffer. Mechanical properties were measured using three sensors: drop impact, resonance frequency and cyclic deformation. Classification algorithms for quality sorting of fruit based on multi-sensory data were developed and implemented. The algorithms included a dynamic artificial neural network, a back propagation neural network and multiple linear regression. Results indicated that classification based on multiple sensors may be applied in real-time sorting and can improve overall classification. Advanced image processing algorithms were developed for shape determination, bruise and stem identification and general color and color homogeneity. An unsupervised method was developed to extract necessary vision features. The primary advantage of the algorithms developed is their ability to learn to determine the visual quality of almost any fruit or vegetable with no need for specific modification and no a-priori knowledge. Moreover, since there is no assumption as to the type of blemish to be characterized, the algorithm is capable of distinguishing between stems and bruises. This enables sorting of fruit without knowing the fruits' orientation. A new algorithm for on-line clustering of data was developed. The algorithm's adaptability is designed to overcome some of the difficulties encountered when incrementally clustering sparse data and preserves information even with memory constraints. Large quantities of data (many images) of high dimensionality (due to multiple sensors) and new information arriving incrementally (a function of the temporal dynamics of any natural process) can now be processed. Furhermore, since the learning is done on-line, it can be implemented in real-time. The methodology developed was tested to determine external quality of tomatoes based on visual information. An improved model for color sorting which is stable and does not require recalibration for each season was developed for color determination. Excellent classification results were obtained for both color and firmness classification. Results indicted that maturity classification can be obtained using a drop-impact and a vision sensor in order to predict the storability and marketing of harvested fruits. In conclusion: We have been able to define quantitatively the critical parameters in the quality sorting and grading of both fresh market cantaloupes and tomatoes. We have been able to accomplish this using nondestructive measurements and in a manner consistent with expert human grading and in accordance with market acceptance. This research constructed and used large databases of both commodities, for comparative evaluation and optimization of expert system, statistical and/or neural network models. The models developed in this research were successfully tested, and should be applicable to a wide range of other fruits and vegetables. These findings are valuable for the development of on-line grading and sorting of agricultural produce through the incorporation of multiple measurement inputs that rapidly define quality in an automated manner, and in a manner consistent with the human graders and inspectors.