WorldWideScience

Sample records for profile sensor electronic

  1. Wireless Biological Electronic Sensors.

    Science.gov (United States)

    Cui, Yue

    2017-10-09

    The development of wireless biological electronic sensors could open up significant advances for both fundamental studies and practical applications in a variety of areas, including medical diagnosis, environmental monitoring, and defense applications. One of the major challenges in the development of wireless bioelectronic sensors is the successful integration of biosensing units and wireless signal transducers. In recent years, there are a few types of wireless communication systems that have been integrated with biosensing systems to construct wireless bioelectronic sensors. To successfully construct wireless biological electronic sensors, there are several interesting questions: What types of biosensing transducers can be used in wireless bioelectronic sensors? What types of wireless systems can be integrated with biosensing transducers to construct wireless bioelectronic sensors? How are the electrical sensing signals generated and transmitted? This review will highlight the early attempts to address these questions in the development of wireless biological electronic sensors.

  2. Graphene Electronic Tattoo Sensors.

    Science.gov (United States)

    Kabiri Ameri, Shideh; Ho, Rebecca; Jang, Hongwoo; Tao, Li; Wang, Youhua; Wang, Liu; Schnyer, David M; Akinwande, Deji; Lu, Nanshu

    2017-08-22

    Tattoo-like epidermal sensors are an emerging class of truly wearable electronics, owing to their thinness and softness. While most of them are based on thin metal films, a silicon membrane, or nanoparticle-based printable inks, we report sub-micrometer thick, multimodal electronic tattoo sensors that are made of graphene. The graphene electronic tattoo (GET) is designed as filamentary serpentines and fabricated by a cost- and time-effective "wet transfer, dry patterning" method. It has a total thickness of 463 ± 30 nm, an optical transparency of ∼85%, and a stretchability of more than 40%. The GET can be directly laminated on human skin just like a temporary tattoo and can fully conform to the microscopic morphology of the surface of skin via just van der Waals forces. The open-mesh structure of the GET makes it breathable and its stiffness negligible. A bare GET is able to stay attached to skin for several hours without fracture or delamination. With liquid bandage coverage, a GET may stay functional on the skin for up to several days. As a dry electrode, GET-skin interface impedance is on par with medically used silver/silver-chloride (Ag/AgCl) gel electrodes, while offering superior comfort, mobility, and reliability. GET has been successfully applied to measure electrocardiogram (ECG), electromyogram (EMG), electroencephalogram (EEG), skin temperature, and skin hydration.

  3. Electronically-Scanned Pressure Sensors

    Science.gov (United States)

    Coe, C. F.; Parra, G. T.; Kauffman, R. C.

    1984-01-01

    Sensors not pneumatically switched. Electronic pressure-transducer scanning system constructed in modular form. Pressure transducer modules and analog to digital converter module small enough to fit within cavities of average-sized wind-tunnel models. All switching done electronically. Temperature controlled environment maintained within sensor modules so accuracy maintained while ambient temperature varies.

  4. Advancing profiling sensors with a wireless approach.

    Science.gov (United States)

    Galvis, Alex; Russomanno, David J

    2012-11-22

    The notion of a profiling sensor was first realized by a Near-Infrared (N-IR) retro-reflective prototype consisting of a vertical column of wired sparse detectors. This paper extends that prior work and presents a wireless version of a profiling sensor as a collection of sensor nodes. The sensor incorporates wireless sensing elements, a distributed data collection and aggregation scheme, and an enhanced classification technique. In this novel approach, a base station pre-processes the data collected from the sensor nodes and performs data re-alignment. A back-propagation neural network was also developed for the wireless version of the N-IR profiling sensor that classifies objects into the broad categories of human, animal or vehicle with an accuracy of approximately 94%. These enhancements improve deployment options as compared with the first generation of wired profiling sensors, possibly increasing the application scenarios for such sensors, including intelligent fence applications.

  5. Sensor Arrays and Electronic Tongue Systems

    Directory of Open Access Journals (Sweden)

    Manel del Valle

    2012-01-01

    Full Text Available This paper describes recent work performed with electronic tongue systems utilizing electrochemical sensors. The electronic tongues concept is a new trend in sensors that uses arrays of sensors together with chemometric tools to unravel the complex information generated. Initial contributions and also the most used variant employ conventional ion selective electrodes, in which it is named potentiometric electronic tongue. The second important variant is the one that employs voltammetry for its operation. As chemometric processing tool, the use of artificial neural networks as the preferred data processing variant will be described. The use of the sensor arrays inserted in flow injection or sequential injection systems will exemplify attempts made to automate the operation of electronic tongues. Significant use of biosensors, mainly enzyme-based, to form what is already named bioelectronic tongue will be also presented. Application examples will be illustrated with selected study cases from the Sensors and Biosensors Group at the Autonomous University of Barcelona.

  6. Sensors: From biosensors to the electronic nose

    Directory of Open Access Journals (Sweden)

    Aparicio, Ramón

    2002-03-01

    Full Text Available The recent advances in sensor devices have allowed the developing of new applications in many technological fields. This review describes the current state-of-the-art of this sensor technology, placing special emphasis on the food applications. The design, technology and sensing mechanism of each type of sensor are analysed. A description of the main characteristics of the electronic nose and electronic tongue (taste sensors is also given. Finally, the applications of some statistical procedures in sensor systems are described briefly.Los recientes avances en los sistemas de sensores han permitido el desarrollo de nuevas aplicaciones en muchos campos tecnológicos. Este artículo de revisión describe el estado actual de esta nueva tecnología, con especial énfasis en las aplicaciones alimentarias. El diseño, la tecnología y el mecanismo sensorial de cada tipo de sensor son analizados en el artículo. También se describen las principales características de la nariz y la lengua electrónica (sensores de sabor. Finalmente, se describe brevemente el uso de algunos procedimientos estadísticos en sistemas de sensores.

  7. Adaptive Sensing Based on Profiles for Sensor Systems

    Directory of Open Access Journals (Sweden)

    Yoshiteru Ishida

    2009-10-01

    Full Text Available This paper proposes a profile-based sensing framework for adaptive sensor systems based on models that relate possibly heterogeneous sensor data and profiles generated by the models to detect events. With these concepts, three phases for building the sensor systems are extracted from two examples: a combustion control sensor system for an automobile engine, and a sensor system for home security. The three phases are: modeling, profiling, and managing trade-offs. Designing and building a sensor system involves mapping the signals to a model to achieve a given mission.

  8. ATLAS pixel detector electronics and sensors

    Energy Technology Data Exchange (ETDEWEB)

    Aad, G; Bernardet, K [CPPM, Aix-Marseille Universite, CNRS/IN2P3, Marseille (France); Ackers, M; Barbero, M B [Physikalisches Institut der Universitaet Bonn, Nussallee 12, D - 53115 Bonn (Germany); Alberti, F A; Aleppo, M; Alimonti, G; Andreani, A; Andreazza, A [INFN Milano, via Celoria 16, IT - 20133 Milano (Italy); Alonso, J; Anderssen, E C; Arguin, J-F; Beringer, J [Lawrence Berkeley National Laboratory and University of California, Physics Division MS50B-6227, 1 Cyclotron Road, Berkeley, CA 94720, United States of America (United States); Arms, K E [Ohio State University, 191 West Woodruff Ave, Columbus, OH 43210-1117, United States of America (United States); Barberis, D; Beccherle, R B [INFN Genova, via Dodecaneso 33, IT - 16146 Genova (Italy); Bazalova, M [Institute of Physics, Academy of Sciences of the Czech Republic Na Slovance 2, CZ - 18221 Praha 8 (Czech Republic); Becks, K H; Bellina, F [Bergische Universitaet, Fachbereich C, Physik Postfach 100127, Gauss-Strasse 20, D- 42097 Wuppertal (Germany); Behera, P K [203 VAN ALLEN HALL, IOWA CITY IA 52242-1479, United States of America (United States)], E-mail: MGGilchriese@lbl.gov (and others)

    2008-07-15

    The silicon pixel tracking system for the ATLAS experiment at the Large Hadron Collider is described and the performance requirements are summarized. Detailed descriptions of the pixel detector electronics and the silicon sensors are given. The design, fabrication, assembly and performance of the pixel detector modules are presented. Data obtained from test beams as well as studies using cosmic rays are also discussed.

  9. Airflow Simulations around OA Intake Louver with Electronic Velocity Sensors

    Energy Technology Data Exchange (ETDEWEB)

    Han, Hwataik; Sullivan, Douglas P.; Fisk, William J.

    2009-04-01

    It is important to control outdoor airflow rates into HVAC systems in terms of energy conservation and healthy indoor environment. Technologies are being developed to measure outdoor air (OA) flow rates through OA intake louvers on a real time basis. The purpose of this paper is to investigate the airflow characteristics through an OA intake louver numerically in order to provide suggestions for sensor installations. Airflow patterns are simulated with and without electronic air velocity sensors within cylindrical probes installed between louver blades or at the downstream face of the louver. Numerical results show quite good agreements with experimental data, and provide insights regarding measurement system design. The simulations indicate that velocity profiles are more spatially uniform at the louver outlet relative to between louver blades, that pressure drops imposed by the sensor bars are smaller with sensor bars at the louver outlet, and that placement of the sensor bars between louver blades substantially increases air velocities inside the louver. These findings suggest there is an advantage to placing the sensor bars at the louver outlet face.

  10. Parametric dependencies of JET electron temperature profiles

    Energy Technology Data Exchange (ETDEWEB)

    Schunke, B. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking; Imre, K.; Riedel, K. [New York Univ., NY (United States)

    1994-07-01

    The JET Ohmic, L-Mode and H-Mode electron temperature profiles obtained from the LIDAR Thomson Scattering Diagnostic are parameterized in terms of the normalized flux parameter and a set of the engineering parameters like plasma current, toroidal field, line averages electron density... It is shown that the electron temperature profiles fit a log-additive model well. It is intended to use the same model to predict the profile shape for D-T discharges in JET and in ITER. 2 refs., 5 figs.

  11. Towards a Chemiresistive Sensor-Integrated Electronic Nose: A Review

    OpenAIRE

    Kea-Tiong Tang; Shih-Wen Chiu

    2013-01-01

    Electronic noses have potential applications in daily life, but are restricted by their bulky size and high price. This review focuses on the use of chemiresistive gas sensors, metal-oxide semiconductor gas sensors and conductive polymer gas sensors in an electronic nose for system integration to reduce size and cost. The review covers the system design considerations and the complementary metal-oxide-semiconductor integrated technology for a chemiresistive gas sensor electronic nose, includi...

  12. An Electron Beam Profile Instrument Based on FBGs

    Directory of Open Access Journals (Sweden)

    Dan Sporea

    2014-08-01

    Full Text Available Along with the dose rate and the total irradiation dose measurements, the knowledge of the beam localization and the beam profile/energy distribution in the beam are parameters of interest for charged particle accelerator installations when they are used in scientific investigations, industrial applications or medical treatments. The transverse profile of the beam, its position, its centroid location, and its focus or flatness depend on the instrument operating conditions or on the beam exit setup. Proof-of-concept of a new type of charged particle beam diagnostics based on fiber Bragg gratings (FBGs was demonstrated. Its operating principle relies on the measurement of the peak wavelength changes for an array of FBG sensors as function of the temperature following the exposure to an electron beam. Periodically, the sensor irradiation is stopped and the FBG are force cooled to a reference temperature with which the temperature influencing each sensor during beam exposure is compared. Commercially available FBGs, and FBGs written in radiation resistant optical fibers, were tested under electron beam irradiation in order to study their possible use in this application.

  13. Electronics Technology. Tech Prep Competency Profile.

    Science.gov (United States)

    Lakeland Tech Prep Consortium, Kirtland, OH.

    This tech prep competency profile covers the occupation of electronics technician. Section 1 provides the occupation definition. Section 2 lists development committee members. Section 3 provides the leveling codes--abbreviations for grade level, (by the end of grade 12, by the end of associate degree), academic codes (communications, math, or…

  14. Glidersonde, a Meteorological Optical Profiling Sensor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The "Glidersonde"is a UAV-deployed environmental sensor suite that is air-deployed and glides into denied or hazardous areas including volcanoes or nuclear...

  15. Electron beam diagnostic system using computed tomography and an annular sensor

    Science.gov (United States)

    Elmer, John W.; Teruya, Alan T.

    2015-08-11

    A system for analyzing an electron beam including a circular electron beam diagnostic sensor adapted to receive the electron beam, the circular electron beam diagnostic sensor having a central axis; an annular sensor structure operatively connected to the circular electron beam diagnostic sensor, wherein the sensor structure receives the electron beam; a system for sweeping the electron beam radially outward from the central axis of the circular electron beam diagnostic sensor to the annular sensor structure wherein the electron beam is intercepted by the annular sensor structure; and a device for measuring the electron beam that is intercepted by the annular sensor structure.

  16. Towards a Chemiresistive Sensor-Integrated Electronic Nose: A Review

    Directory of Open Access Journals (Sweden)

    Kea-Tiong Tang

    2013-10-01

    Full Text Available Electronic noses have potential applications in daily life, but are restricted by their bulky size and high price. This review focuses on the use of chemiresistive gas sensors, metal-oxide semiconductor gas sensors and conductive polymer gas sensors in an electronic nose for system integration to reduce size and cost. The review covers the system design considerations and the complementary metal-oxide-semiconductor integrated technology for a chemiresistive gas sensor electronic nose, including the integrated sensor array, its readout interface, and pattern recognition hardware. In addition, the state-of-the-art technology integrated in the electronic nose is also presented, such as the sensing front-end chip, electronic nose signal processing chip, and the electronic nose system-on-chip.

  17. Towards a Chemiresistive Sensor-Integrated Electronic Nose: A Review

    Science.gov (United States)

    Chiu, Shih-Wen; Tang, Kea-Tiong

    2013-01-01

    Electronic noses have potential applications in daily life, but are restricted by their bulky size and high price. This review focuses on the use of chemiresistive gas sensors, metal-oxide semiconductor gas sensors and conductive polymer gas sensors in an electronic nose for system integration to reduce size and cost. The review covers the system design considerations and the complementary metal-oxide-semiconductor integrated technology for a chemiresistive gas sensor electronic nose, including the integrated sensor array, its readout interface, and pattern recognition hardware. In addition, the state-of-the-art technology integrated in the electronic nose is also presented, such as the sensing front-end chip, electronic nose signal processing chip, and the electronic nose system-on-chip. PMID:24152879

  18. Electronic cigarette solutions and resultant aerosol profiles.

    Science.gov (United States)

    Herrington, Jason S; Myers, Colton

    2015-10-30

    Electronic cigarettes (e-cigarettes) are growing in popularity exponentially. Despite their ever-growing acceptance, their aerosol has not been fully characterized. The current study focused on evaluating e-cigarette solutions and their resultant aerosol for potential differences. A simple sampling device was developed to draw e-cigarette aerosol into a multi-sorbent thermal desorption (TD) tube, which was then thermally extracted and analyzed via a gas chromatography (GC) mass spectrometry (GC-MS) method. This novel application provided detectable levels of over one hundred fifteen volatile organic compounds (VOCs) and semivolatile organic compounds (SVOCs) from a single 40mL puff. The aerosol profiles from four commercially available e-cigarettes were compared to their respective solution profiles with the same GC-MS method. Solution profiles produced upwards of sixty four unidentified and identified (some only tentatively) constituents and aerosol profiles produced upwards of eighty two compounds. Results demonstrated distinct analyte profiles between liquid and aerosol samples. Most notably, formaldehyde, acetaldehyde, acrolein, and siloxanes were found in the aerosol profiles; however, these compounds were never present in the solutions. These results implicate the aerosolization process in the formation of compounds not found in solutions; have potential implications for human health; and stress the need for an emphasis on electronic cigarette aerosol testing. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  19. Wearable electronics sensors for safe and healthy living

    CERN Document Server

    2015-01-01

    This edited book contains invited papers from renowned experts working in the field of Wearable Electronics Sensors. It includes 14 chapters describing recent advancements in the area of Wearable Sensors, Wireless Sensors and Sensor Networks, Protocols, Topologies, Instrumentation architectures, Measurement techniques, Energy harvesting and scavenging, Signal processing, Design and Prototyping. The book will be useful for engineers, scientist and post-graduate students as a reference book for their research on wearable sensors, devices and technologies which is experiencing a period of rapid growth driven by new applications such as heart rate monitors, smart watches, tracking devices and smart glasses.  .

  20. Demonstration of a prototype hydrogen sensor and electronics package

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Amanda S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Brosha, Eric [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-08-03

    This is a progress report for the demonstration of a prototype hydrogen sensor and electronics package. There are five tasks associated with this, and four have been completed as of August 2016: Station Demonstration and Site Recommendation, Order Sensor Equipment, Build Sensors, and Install Sensors. The final task to be completed is Sensor Demonstration and Data Analysis, and expected completion date is January 26, 2017. This progress report details each of the tasks and goes into detail about what is currently being worked on, along with the budget and planned work for July 27, 2016 to January 26, 2017.

  1. Dopant profiling with the scanning electron microscope

    CERN Document Server

    Elliott, S L

    2001-01-01

    This dissertation is a detailed study of dopant profiling with the scanning electron microscope (SEM) using secondary electrons. The technique has been applied to a wide variety of doped silicon, gallium arsenide and gallium nitride semiconductor test structures as well as a metal-oxide field effect transistor and several light emitting diodes. A concise set of guide-lines are provided for users of this technique, including the optimum SEM operating conditions that should be used for maximum contrast, an image manipulation procedure, and the resolution and sensitivity limits that can be expected. Dopant contrast observed with the SEM has been studied over the past few years by a number of researchers, and a theory for the contrast has evolved. This theory considers the patch fields outside the specimen to be the dominant factor determining the secondary electron intensity. In this dissertation the contrast mechanism has been further investigated by examining the contrast at different temperatures and after su...

  2. Prospects for SiC electronics and sensors

    OpenAIRE

    Nick G. Wright; Alton B. Horsfall; Vassilevski, Konstantin

    2008-01-01

    There has been substantial international research effort in the development of SiC electronics over the last ten years. With promising applications in power electronics, hostile-environment electronics, and sensors, there is considerable industrial interest in SiC as a material for electronics. However, issues relating to crystal growth and the difficulties of material processing have restricted SiC devices to relatively limited use to date. The eventual success of SiC as an electronic techno...

  3. Miniature sensor suitable for electronic nose applications

    DEFF Research Database (Denmark)

    Pinnaduwage, L. A.; Gehl, A. C.; Allman, S. L.

    2007-01-01

    selective detection. In order to keep the overall detector unit small, miniature sensors with sufficient sensitivity of detection will be needed.We report sensitive detection of dimethyl methylphosphonate DMMP, a stimulant for the nerve agents, using a miniature sensor unit based on piezoresistive...

  4. Profiling of Current Transients in Capacitor Type Diamond Sensors

    Directory of Open Access Journals (Sweden)

    Eugenijus Gaubas

    2015-06-01

    Full Text Available The operational characteristics of capacitor-type detectors based on HPHT and CVD diamond have been investigated using perpendicular and parallel injection of carrier domain regimes. Simulations of the drift-diffusion current transients have been implemented by using dynamic models based on Shockley-Ramo’s theorem, under injection of localized surface domains and of bulk charge carriers. The bipolar drift-diffusion regimes have been analyzed for the photo-induced bulk domain (packet of excess carriers. The surface charge formation and polarization effects dependent on detector biasing voltage have been revealed. The screening effects ascribed to surface charge and to dynamics of extraction of the injected bulk excess carrier domain have been separated and explained. The parameters of drift mobility of the electrons μe = 4000 cm2/Vs and holes μh = 3800 cm2/Vs have been evaluated for CVD diamond using the perpendicular profiling of currents. The coefficient of carrier ambipolar diffusion Da = 97 cm2/s and the carrier recombination lifetime τR,CVD ≌ 110 ns in CVD diamond were extracted by combining analysis of the transients of the sensor current and the microwave probed photoconductivity. The carrier trapping with inherent lifetime τR,HPHT ≌ 2 ns prevails in HPHT diamond.

  5. In plane optical sensor based on organic electronic devices

    NARCIS (Netherlands)

    Koetse, M.M; Rensing, P.A.; Heck, G.T. van; Sharpe, R.B.A.; Allard, B.A.M.; Wieringa, F.P.; Kruijt, P.G.M.; Meulendijks, N.M.M.; Jansen, H.; Schoo, H.F.M.

    2008-01-01

    Sensors based on organic electronic devices are emerging in a wide range of application areas. Here we present a sensor platform using organic light emitting diodes (OLED) and organic photodiodes (OPD) as active components. By means of lamination and interconnection technology the functional foils

  6. Marine Profiles for OGC Sensor Web Enablement Standards

    Science.gov (United States)

    Jirka, Simon

    2016-04-01

    The use of OGC Sensor Web Enablement (SWE) standards in oceanology is increasing. Several projects are developing SWE-based infrastructures to ease the sharing of marine sensor data. This work ranges from developments on sensor level to efforts addressing interoperability of data flows between observatories and organisations. The broad range of activities using SWE standards leads to a risk of diverging approaches how the SWE specifications are applied. Because the SWE standards are designed in a domain independent manner, they intentionally offer a high degree of flexibility enabling implementation across different domains and usage scenarios. At the same time this flexibility allows one to achieve similar goals in different ways. To avoid interoperability issues, an agreement is needed on how to apply SWE concepts and how to use vocabularies in a common way that will be shared by different projects, implementations, and users. To address this need, partners from several projects and initiatives (AODN, BRIDGES, envri+, EUROFLEETS/EUROFLEETS2, FixO3, FRAM, IOOS, Jerico/Jerico-Next, NeXOS, ODIP/ODIP II, RITMARE, SeaDataNet, SenseOcean, X-DOMES) have teamed up to develop marine profiles of OGC SWE standards that can serve as a common basis for developments in multiple projects and organisations. The following aspects will be especially considered: 1.) Provision of metadata: For discovering sensors/instruments as well as observation data, to facilitate the interpretation of observations, and to integrate instruments in sensor platforms, the provision of metadata is crucial. Thus, a marine profile of the OGC Sensor Model Language 2.0 (SensorML 2.0) will be developed allowing to provide metadata for different levels (e.g. observatory, instrument, and detector) and sensor types. The latter will enable metadata of a specific type to be automatically inherited by all devices/sensors of the same type. The application of further standards such as OGC PUCK will benefit from

  7. Micromachined capacitive pressure sensor with signal conditioning electronics

    DEFF Research Database (Denmark)

    Fragiacomo, Giulio

    Micromachined capacitive pressure sensors for harsh environment together with interfacing electronic circuits have been studied in this project. Micro-electromechanical systems (MEMS) have been proposed as substitutes for macro scale sensor’s systems in many different fields and are the only...... a great deal of sensors are used. Pressure sensors are among the most successful MEMS and are used in a huge variety of applications. In this project an absolute capacitive pressure sensor has been developed with the aim to integrate it in pump control systems to improve the efficiency of the pump...

  8. Adaptive method for electron bunch profile prediction

    Directory of Open Access Journals (Sweden)

    Alexander Scheinker

    2015-10-01

    Full Text Available We report on an experiment performed at the Facility for Advanced Accelerator Experimental Tests (FACET at SLAC National Accelerator Laboratory, in which a new adaptive control algorithm, one with known, bounded update rates, despite operating on analytically unknown cost functions, was utilized in order to provide quasi-real-time bunch property estimates of the electron beam. Multiple parameters, such as arbitrary rf phase settings and other time-varying accelerator properties, were simultaneously tuned in order to match a simulated bunch energy spectrum with a measured energy spectrum. The simple adaptive scheme was digitally implemented using matlab and the experimental physics and industrial control system. The main result is a nonintrusive, nondestructive, real-time diagnostic scheme for prediction of bunch profiles, as well as other beam parameters, the precise control of which are important for the plasma wakefield acceleration experiments being explored at FACET.

  9. A Review of Infrared Readout Electronics for Space Science Sensors

    Science.gov (United States)

    Pain, Bedabrata; Fossum, Eric R.

    1993-01-01

    A review of infrared readout electornics for space science sensors is presented. General requirements for scientific IR FPA readout are discussed. Specific approaches to the unit cell electronics are described with respect to operation, complexity, noise and other operating parameters. Recent achievements in IR FPA readout electronics are reviewed. Implementation technologies for realization of IR FPA readout electronics are discussed. Future directions for addressing NASA and other scientific users' needs are suggested.

  10. A systematic profile/feature-based intelligence for spectral sensors.

    Energy Technology Data Exchange (ETDEWEB)

    Vogt, M.C.

    2000-10-16

    Argonne National Laboratory (ANL) has been creating a special-purpose software-engineering tool to support research and development of spectrum-output-type [chemical] sensors. The modular software system is called SAGE, the Sensor Algorithm Generation Environment and includes general-purpose signal conditioning algorithms (GP/SAGE) as well as intelligent classifiers, pattern recognizes, response accelerators, and sensitivity analyzers. GP/SAGE is an implementation of an approach for delivering a level of encapsulated intelligence to a wide range of sensors and instruments. It capitalizes on the genene classification and analysis needed to process most profile-type data. The GP/SAGE native data format is a generalized one-dimensional vector, signature, or spectrum. GP/SAGE modules form a computer-aided software engineering (CASE) workbench where users can experiment with various conditioning, filtering, and pattern recognition stages, then automatically generate final algorithm source code for data acquisition and analysis systems. SAGE was designed to free the [chemical] sensor developer from the signal processing allowing them to focus on understanding and improving the basic sensing mechanisms. The SAGE system's strength is its creative application of advanced neural computing techniques to response-vector and response-surface data, affording new insight and perspectives with regard to phenomena being studied for sensor development.

  11. Error analysis for mesospheric temperature profiling by absorptive occultation sensors

    Directory of Open Access Journals (Sweden)

    M. J. Rieder

    Full Text Available An error analysis for mesospheric profiles retrieved from absorptive occultation data has been performed, starting with realistic error assumptions as would apply to intensity data collected by available high-precision UV photodiode sensors. Propagation of statistical errors was investigated through the complete retrieval chain from measured intensity profiles to atmospheric density, pressure, and temperature profiles. We assumed unbiased errors as the occultation method is essentially self-calibrating and straight-line propagation of occulted signals as we focus on heights of 50–100 km, where refractive bending of the sensed radiation is negligible. Throughout the analysis the errors were characterized at each retrieval step by their mean profile, their covariance matrix and their probability density function (pdf. This furnishes, compared to a variance-only estimation, a much improved insight into the error propagation mechanism. We applied the procedure to a baseline analysis of the performance of a recently proposed solar UV occultation sensor (SMAS – Sun Monitor and Atmospheric Sounder and provide, using a reasonable exponential atmospheric model as background, results on error standard deviations and error correlation functions of density, pressure, and temperature profiles. Two different sensor photodiode assumptions are discussed, respectively, diamond diodes (DD with 0.03% and silicon diodes (SD with 0.1% (unattenuated intensity measurement noise at 10 Hz sampling rate. A factor-of-2 margin was applied to these noise values in order to roughly account for unmodeled cross section uncertainties. Within the entire height domain (50–100 km we find temperature to be retrieved to better than 0.3 K (DD / 1 K (SD accuracy, respectively, at 2 km height resolution. The results indicate that absorptive occultations acquired by a SMAS-type sensor could provide mesospheric profiles of fundamental variables such as temperature with

  12. Electronics for LabView Based Piezoresistive Microcantilever Sensor System

    Directory of Open Access Journals (Sweden)

    Timothy L. Porter

    2006-06-01

    Full Text Available A simple, low-cost electronic interface suitable for use with piezoresistive microcantilever-based sensors was developed. This interface uses the USB bus of any computer or laptop to communicate with the sensor via SPI commands. The primary user interface is LabView. This system was used with several “embedded” piezoresistive microcantilever sensing applications, including both liquid-phase and gas-phase sensing.

  13. MGS RS: IONOSPHERIC ELECTRON DENSITY PROFILES V1.0

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains 5600 ionospheric electron density profiles (EDS files) derived from Mars Global Surveyor (MGS) radio occultation data. The profiles were...

  14. Biogeochemical sensor performance in the SOCCOM profiling float array

    Science.gov (United States)

    Johnson, Kenneth S.; Plant, Joshua N.; Coletti, Luke J.; Jannasch, Hans W.; Sakamoto, Carole M.; Riser, Stephen C.; Swift, Dana D.; Williams, Nancy L.; Boss, Emmanuel; Haëntjens, Nils; Talley, Lynne D.; Sarmiento, Jorge L.

    2017-08-01

    The Southern Ocean Carbon and Climate Observations and Modeling (SOCCOM) program has begun deploying a large array of biogeochemical sensors on profiling floats in the Southern Ocean. As of February 2016, 86 floats have been deployed. Here the focus is on 56 floats with quality-controlled and adjusted data that have been in the water at least 6 months. The floats carry oxygen, nitrate, pH, chlorophyll fluorescence, and optical backscatter sensors. The raw data generated by these sensors can suffer from inaccurate initial calibrations and from sensor drift over time. Procedures to correct the data are defined. The initial accuracy of the adjusted concentrations is assessed by comparing the corrected data to laboratory measurements made on samples collected by a hydrographic cast with a rosette sampler at the float deployment station. The long-term accuracy of the corrected data is compared to the GLODAPv2 data set whenever a float made a profile within 20 km of a GLODAPv2 station. Based on these assessments, the fleet average oxygen data are accurate to 1 ± 1%, nitrate to within 0.5 ± 0.5 µmol kg-1, and pH to 0.005 ± 0.007, where the error limit is 1 standard deviation of the fleet data. The bio-optical measurements of chlorophyll fluorescence and optical backscatter are used to estimate chlorophyll a and particulate organic carbon concentration. The particulate organic carbon concentrations inferred from optical backscatter appear accurate to with 35 mg C m-3 or 20%, whichever is larger. Factors affecting the accuracy of the estimated chlorophyll a concentrations are evaluated.type="synopsis">type="main">Plain Language SummaryThe ocean science community must move toward greater use of autonomous platforms and sensors if we are to extend our knowledge of the effects of climate driven change within the ocean. Essential to this shift in observing strategies is an understanding of the performance that can be obtained from biogeochemical sensors on platforms

  15. Design of the MEMS Piezoresistive Electronic Heart Sound Sensor.

    Science.gov (United States)

    Zhang, Guojun; Liu, Mengran; Guo, Nan; Zhang, Wendong

    2016-11-07

    This paper proposes the electronic heart sound sensor, based on the piezoresistive principle and MEMS (Micro-Electro-Mechanical System) technology. Firstly, according to the characteristics of heart sound detection, the double-beam-block microstructure has been proposed, and the theoretical analysis and finite element method (FEM) simulation have been carried out. Combined with the natural frequency response of the heart sound (20~600 Hz), its structure sizes have been determined. Secondly, the processing technology of the microstructure with the stress concentration grooves has been developed. The material and sizes of the package have been determined by the three-layer medium transmission principle. Lastly, the MEMS piezoresistive electronic heart sound sensor has been tested compared with the 3200-type electronic stethoscope from 3M (São Paulo, MN, USA). The test results show that the heart sound waveform tested by the MEMS electronic heart sound sensor are almost the same as that tested by the 3200-type electronic stethoscope. Moreover, its signal-to-noise ratio is significantly higher. Compared with the traditional stethoscope, the MEMS heart sound sensor can provide the first and second heart sounds containing more abundant information about the lesion. Compared with the 3200-type electronic stethoscope from 3M, it has better performance and lower cost.

  16. Performance enhancement of electronic sensor through mask-less lithography

    KAUST Repository

    Nag, Anindya

    2016-03-30

    The escalating applications of miniaturized sensors have led the microelectronics industry to stay abreast with the precise micro-fabrication technologies. The following article describes a new technique for the fabrication of miniaturized interdigitated capacitive sensors that own highly sensitive and real-time detections capabilities. In standard lithographic procedure, the sensors are fabricated applying different photoresist materials that give rise to the variable characteristic profile of the fabricated product. Single crystal p-doped Silicon wafer was used as a substrate material due to its advantageous properties over Germanium. Heidelberg system was used for the maskless lithographic patterning of the new interdigital sensors on a silicon substrate. The process was carried out in a clean room in the absence of ultraviolet light at a fixed temperature. The fabricated sensors were used for inflammable gas sensing application. Electrochemical Impedance Spectroscopy was applied to read the resistive and capacitive impedance measured by the sensor. The results proclaimed that the fabricated sensors own better performance in LPG detection as compared to its commercial counterparts.

  17. Flexible Electronics Sensors for Tactile Multi-Touching

    Directory of Open Access Journals (Sweden)

    Shao-Hsing Yeh

    2009-02-01

    Full Text Available Flexible electronics sensors for tactile applications in multi-touch sensing and large scale manufacturing were designed and fabricated. The sensors are based on polyimide substrates, with thixotropy materials used to print organic resistances and a bump on the top polyimide layer. The gap between the bottom electrode layer and the resistance layer provides a buffer distance to reduce erroneous contact during large bending. Experimental results show that the top membrane with a bump protrusion and a resistance layer had a large deflection and a quick sensitive response. The bump and resistance layer provided a concentrated von Mises stress force and inertial force on the top membrane center. When the top membrane had no bump, it had a transient response delay time and took longer to reach steady-state. For printing thick structures of flexible electronics sensors, diffusion effects and dimensional shrinkages can be improved by using a paste material with a high viscosity. Linear algorithm matrixes with Gaussian elimination and control system scanning were used for multi-touch detection. Flexible electronics sensors were printed with a resistance thickness of about 32 µm and a bump thickness of about 0.2 mm. Feasibility studies show that printing technology is appropriate for large scale manufacturing, producing sensors at a low cost.

  18. A micromachined surface stress sensor with electronic readout

    NARCIS (Netherlands)

    Carlen, Edwin; Weinberg, M.S.; Zapata, A.M.; Borenstein, J.T.

    2008-01-01

    A micromachined surface stress sensor has been fabricated and integrated off chip with a low-noise, differential capacitance, electronic readout circuit. The differential capacitance signal is modulated with a high frequency carrier signal, and the output signal is synchronously demodulated and

  19. CVD diamond for electronic devices and sensors

    CERN Document Server

    2009-01-01

    Synthetic diamond is diamond produced by using chemical or physical processes. Like naturally occurring diamond it is composed of a three-dimensional carbon crystal. Due to its extreme physical properties, synthetic diamond is used in many industrial applications, such as drill bits and scratch-proof coatings, and has the potential to be used in many new application areas A brand new title from the respected Wiley Materials for Electronic and Optoelectronic Applications series, this title is the most up-to-date resource for diamond specialists. Beginning with an introduction to the pr

  20. Electron Density Profile Data Contains Virtual Height/Frequency Pairs from a Profile or Profiles (Composite Months) of Ionograms

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Electron Density Profile, N(h), data set contains both individual profiles and composite months. The data consist of virtual height/frequency pairs from a...

  1. Developing sensor activity relationships for the JPL electronic nose sensors using molecular modeling and QSAR techniques

    Science.gov (United States)

    Shevade, A. V.; Ryan, M. A.; Homer, M. L.; Jewell, A. D.; Zhou, H.; Manatt, K.; Kisor, A. K.

    2005-01-01

    We report a Quantitative Structure-Activity Relationships (QSAR) study using Genetic Function Approximations (GFA) to describe the polymer-carbon composite sensor activities in the JPL Electronic Nose, when exposed to chemical vapors at parts-per-million concentration levels.

  2. An optical fiber expendable seawater temperature/depth profile sensor

    Science.gov (United States)

    Zhao, Qiang; Chen, Shizhe; Zhang, Keke; Yan, Xingkui; Yang, Xianglong; Bai, Xuejiao; Liu, Shixuan

    2017-10-01

    Marine expendable temperature/depth profiler (XBT) is a disposable measuring instrument which can obtain temperature/depth profile data quickly in large area waters and mainly used for marine surveys, scientific research, military application. The temperature measuring device is a thermistor in the conventional XBT probe (CXBT)and the depth data is only a calculated value by speed and time depth calculation formula which is not an accurate measurement result. Firstly, an optical fiber expendable temperature/depth sensor based on the FBG-LPG cascaded structure is proposed to solve the problems of the CXBT, namely the use of LPG and FBG were used to detect the water temperature and depth, respectively. Secondly, the fiber end reflective mirror is used to simplify optical cascade structure and optimize the system performance. Finally, the optical path is designed and optimized using the reflective optical fiber end mirror. The experimental results show that the sensitivity of temperature and depth sensing based on FBG-LPG cascade structure is about 0.0030C and 0.1%F.S. respectively, which can meet the requirements of the sea water temperature/depth observation. The reflectivity of reflection mirror is in the range from 48.8% to 72.5%, the resonant peak of FBG and LPG are reasonable and the whole spectrum are suitable for demodulation. Through research on the optical fiber XBT (FXBT), the direct measurement of deep-sea temperature/depth profile data can be obtained simultaneously, quickly and accurately. The FXBT is a new all-optical seawater temperature/depth sensor, which has important academic value and broad application prospect and is expected to replace the CXBT in the future.

  3. Graphene-Based Chemical Vapor Sensors for Electronic Nose Applications

    Science.gov (United States)

    Nallon, Eric C.

    An electronic nose (e-nose) is a biologically inspired device designed to mimic the operation of the olfactory system. The e-nose utilizes a chemical sensor array consisting of broadly responsive vapor sensors, whose combined response produces a unique pattern for a given compound or mixture. The sensor array is inspired by the biological function of the receptor neurons found in the human olfactory system, which are inherently cross-reactive and respond to many different compounds. The use of an e-nose is an attractive approach to predict unknown odors and is used in many fields for quantitative and qualitative analysis. If properly designed, an e-nose has the potential to adapt to new odors it was not originally designed for through laboratory training and algorithm updates. This would eliminate the lengthy and costly R&D costs associated with materiel and product development. Although e-nose technology has been around for over two decades, much research is still being undertaken in order to find new and more diverse types of sensors. Graphene is a single-layer, 2D material comprised of carbon atoms arranged in a hexagonal lattice, with extraordinary electrical, mechanical, thermal and optical properties due to its 2D, sp2-bonded structure. Graphene has much potential as a chemical sensing material due to its 2D structure, which provides a surface entirely exposed to its surrounding environment. In this configuration, every carbon atom in graphene is a surface atom, providing the greatest possible surface area per unit volume, so that electron transport is highly sensitive to adsorbed molecular species. Graphene has gained much attention since its discovery in 2004, but has not been realized in many commercial electronics. It has the potential to be a revolutionary material for use in chemical sensors due to its excellent conductivity, large surface area, low noise, and versatile surface for functionalization. In this work, graphene is incorporated into a

  4. The MICROSCOPE Inertial sensors and their flight models electronics

    Science.gov (United States)

    Touboul, Pierre; Boulanger, Damien; Liorzou, Françoise

    2012-07-01

    Dedicated space inertial sensors have been developed for the payload of the MICROSCOPE mission which scientific objective is the test of the universality of free fall at level better than 10-15. This accuracy requires the operation of four inertial sensors on board a specific drag-free satellite, exhibiting resolution of better than 1 femto-g for data integrating period over 20 orbits. Such an outstanding resolution requires the fine electrostatic servo-control of each sensor test mass motion, free of any perturbation along its six degrees of freedom. In addition to a very accurate geometrical sensor core, highly performing electronics architecture is necessary to provide the measurement of the weak electrostatic forces and torques applied to the mass. Capacitive sensing provides the linear and attitude motion of the mass with respect to gold coated electrodes silica parts. Charges are controlled on the electrodes all around the mass to generate adequate electrical field and so electrostatic pressures in order to maintain the mass motionless with respect to the instrument structure. Digital control laws are implemented to deal with both the instrument operation flexibility and the preservation of the weak position sensor noise. The flight model electronics units have been produced and tested. All characteristics have been verified as well as the thermal sensitivities. Description of these units and test results are presented in the paper. These electronics provide not only the scientific data for the General Relativity test but also the data for the satellite orbit and attitude control. The satellite is now under production for a launch in 2016.

  5. Packaging Technologies for High Temperature Electronics and Sensors

    Science.gov (United States)

    Chen, Liangyu; Hunter, Gary W.; Neudeck, Philip G.; Beheim, Glenn M.; Spry, David J.; Meredith, Roger D.

    2013-01-01

    This paper reviews ceramic substrates and thick-film metallization based packaging technologies in development for 500degC silicon carbide (SiC) electronics and sensors. Prototype high temperature ceramic chip-level packages and printed circuit boards (PCBs) based on ceramic substrates of aluminum oxide (Al2O3) and aluminum nitride (AlN) have been designed and fabricated. These ceramic substrate-based chiplevel packages with gold (Au) thick-film metallization have been electrically characterized at temperatures up to 550degC. A 96% alumina based edge connector for a PCB level subsystem interconnection has also been demonstrated recently. The 96% alumina packaging system composed of chip-level packages and PCBs has been tested with high temperature SiC devices at 500degC for over 10,000 hours. In addition to tests in a laboratory environment, a SiC JFET with a packaging system composed of a 96% alumina chip-level package and an alumina printed circuit board mounted on a data acquisition circuit board was launched as a part of the MISSE-7 suite to the International Space Station via a Shuttle mission. This packaged SiC transistor was successfully tested in orbit for eighteen months. A spark-plug type sensor package designed for high temperature SiC capacitive pressure sensors was developed. This sensor package combines the high temperature interconnection system with a commercial high temperature high pressure stainless steel seal gland (electrical feed-through). Test results of a packaged high temperature capacitive pressure sensor at 500degC are also discussed. In addition to the pressure sensor package, efforts for packaging high temperature SiC diode-based gas chemical sensors are in process.

  6. In plane optical sensor based on organic electronic devices

    Science.gov (United States)

    Koetse, Marc; Rensing, Peter; van Heck, Gert; Sharpe, Ruben; Allard, Bart; Wieringa, Fokko; Kruijt, Peter; Meulendijks, Nicole; Jansen, Henk; Schoo, Herman

    2008-08-01

    Sensors based on organic electronic devices are emerging in a wide range of application areas. Here we present a sensor platform using organic light emitting diodes (OLED) and organic photodiodes (OPD) as active components. By means of lamination and interconnection technology the functional foils with OLED and OPD arrays form an in-plane optical sensor platform (IPOS). This platform can be extended with a wireless data and signal processing unit yielding a sensor node. The focus of our research is to engage the node in a healthcare application, in which a bandage is able to monitor the vital signs of a person, a so-called Smart Bandage. One of the principles that is described here is based on measuring the absorption modulation of blood volume induced by the pulse (photoplethysmography). The information from such a bandage could be used to monitor wound healing by measuring the perfusion in the skin. The OLED and OPD devices are manufactured on separate foils and glass substrates by means of printing and coating technologies. Furthermore, the modular approach allows for the application of the optical sensing unit in a variety of other fields including chemical sensing. This, ultimately enables the measurement of a large variety of physiological parameters using the same bandage and the same basic sensor architecture. Here we discuss the build-up of our device in general terms. Specific characteristics of the used OLEDs and OPDs are shown and finally we demonstrate the functionality by simultaneously recorded photoplethysmograms of our device and a clinical pulseoximeter.

  7. Thermal control system for SSF sensor/electronics

    Science.gov (United States)

    Akau, R. L.; Lee, D. E.

    1993-01-01

    A thermal control system was designed for the Space Station Freedom (SSF) sensor/electronics box (SSTACK). Multi-layer insulation and heaters are used to maintain the temperatures of the critical components within their operating and survival temperature limits. Detailed and simplified SSTACK thermal models were developed and temperatures were calculated for worst-case orbital conditions. A comparison between the two models showed very good agreement. Temperature predictions were also compared to measured temperatures from a thermal-vacuum test.

  8. A Single-Cell Electronic Sensor of Toxins

    Science.gov (United States)

    Stupin, D. D.

    2017-11-01

    Here we propose a simple label-free bio-electronic toxin detector based on nondestructive impedance spectroscopy (IS) method with a single living cell as a sensing element. The toxins distort cell membrane, which significantly affects on the impedance level of an electrode, which covered by a cell. This effect could be used for toxin detection. We believe that our bio-sensor will open a new roadmap in water purity purposes and will save many a one lives.

  9. CMOS front-end electronics for radiation sensors

    CERN Document Server

    AUTHOR|(CDS)2071026

    2015-01-01

    This book offers a comprehensive treatment of front-end electronics for radiation detection. It discusses the fundamental principles of signal processing for radiation detectors and describes circuits at the level of functional building blocks, omitting transistor-level implementation. It also covers important system-level topics commonly found in the world of front-end electronics for radiation sensors. The book develops the topics in detail, with a constant focus on practical problems. It also provides real implementation examples that offer insights and stimuli for more experienced engineers already working in the field.

  10. Application of a Heat Flux Sensor in Wind Power Electronics

    Directory of Open Access Journals (Sweden)

    Elvira Baygildina

    2016-06-01

    Full Text Available This paper proposes and investigates the application of the gradient heat flux sensor (GHFS for measuring the local heat flux in power electronics. Thanks to its thinness, the sensor can be placed between the semiconductor module and the heat sink. The GHFS has high sensitivity and yields direct measurements without an interruption to the normal power device operation, which makes it attractive for power electronics applications. The development of systems for monitoring thermal loading and methods for online detection of degradation and failure of power electronic devices is a topical and crucial task. However, online condition monitoring (CM methods, which include heat flux sensors, have received little research attention so far. In the current research, an insulated-gate bipolar transistor (IGBT module-based test setup with the GHFS implemented on the base plate of one of the IGBTs is introduced. The heat flux experiments and the IGBT power losses obtained by simulations show similar results. The findings give clear evidence that the GHFS can provide an attractive condition monitoring method for the thermal loading of power devices.

  11. Gyrokinetic modelling of stationary electron and impurity profiles in tokamaks

    CERN Document Server

    Skyman, Andreas; Tegnered, Daniel

    2014-01-01

    Particle transport due to Ion Temperature Gradient/Trapped Electron (ITG/TE) mode turbulence is investigated using the gyrokinetic code GENE. Both a reduced quasilinear (QL) treatment and nonlinear (NL) simulations are performed for typical tokamak parameters corresponding to ITG dominated turbulence. A selfconsistent treatment is used, where the stationary local profiles are calculated corresponding to zero particle flux simultaneously for electrons and trace impurities. The scaling of the stationary profiles with magnetic shear, safety factor, electron-to-ion temperature ratio, collisionality, toroidal sheared rotation, triangularity, and elongation is investigated. In addition, the effect of different main ion mass on the zero flux condition is discussed. The electron density gradient can significantly affect the stationary impurity profile scaling. It is therefore expected, that a selfconsistent treatment will yield results more comparable to experimental results for parameter scans where the stationary b...

  12. Sensors

    CERN Document Server

    Pigorsch, Enrico

    1997-01-01

    This is the 5th edition of the Metra Martech Directory "EUROPEAN CENTRES OF EXPERTISE - SENSORS." The entries represent a survey of European sensors development. The new edition contains 425 detailed profiles of companies and research institutions in 22 countries. This is reflected in the diversity of sensors development programmes described, from sensors for physical parameters to biosensors and intelligent sensor systems. We do not claim that all European organisations developing sensors are included, but this is a good cross section from an invited list of participants. If you see gaps or omissions, or would like your organisation to be included, please send details. The data base invites the formation of effective joint ventures by identifying and providing access to specific areas in which organisations offer collaboration. This issue is recognised to be of great importance and most entrants include details of collaboration offered and sought. We hope the directory on Sensors will help you to find the ri...

  13. Smart electronics and sensors for IVHS and automobile collision warning antenna systems

    Science.gov (United States)

    Varadan, Vijay K.; Varadan, Vasundara V.

    1995-05-01

    In this paper, the feasibility of using electronically steerable antennas for health monitoring of civil structures and early warning of collapsing bridges to the approaching vehicles is presented. These antennas can also be used in automobile collision warning systems. These antennas are lightweight, low volume, low profile and conformal. They have low fabrication costs and are easily mass produced. They are thin and do not perturb the aerodynamics of a host automobile. Linear, circular, and dual polarization are achieved with simple changes in feed position. Beam steering is accomplished by varying the relative phase between radiating elements. In planar array, both horizontal and vertical beam can be combined to provide full scanning capabilities. Tunable ceramic phase shifters are used in these antennas. The dielectric properties of the ferroelectric material are changed by a bias voltage. In the case of health monitoring of civil structures, these antennas are used in conjunction with ferroelectric sensors. The sensors are fabricated with interdigital transducers printed on a piezoelectric polymer or ceramic type film. They are in turn mounted onto an ultra thin Penn State's novel RF antenna. The wave form measurements may be monitored at a remote location via the antenna in the sensors and the electronically steerable antenna outlined above.

  14. An optimized electronic device for solar power harvesting dedicated to wireless sensor networks

    Energy Technology Data Exchange (ETDEWEB)

    Le Cam, Vincent; Le Maulf, Regis; Lemarchand, Laurent; Martin, William; Le Pen, Mathieu [LUNAM Univ., Bouguenais (France). IFSTTAR, MACS Dept.

    2012-07-01

    For economics as for practical reasons, this last decade, the use and dissemination of wireless sensor networks (WSN) became obvious; particularly in structural heath monitoring (SHM) use-cases where distances between sensors could be long and access to the structure quite difficult. Even if efforts are leaded to design small components and RF modules that ask for low-power, the need of an external source is often necessary. After have acquired knowledge in solar cells as in batteries technologies and methods to control charge/discharge phases as in optimizing algorithms, IFSTTAR laboratory has designed an electronic device that integrates those progress. This electronic device has a quite generic mission: for a panel of batteries chemistry (Lithium, NiMh) and a panel of solar cells sources (frome mW to some W), the system acts as an improved battery charger whatever the load ask for power. The system applies control algorithms based on battery capacity and chemistry profile. It also applies the MPPT (Maximum Power Point Tracking) algorithm. At any time, battery State Of Charge (SOC) can be requested via I2C bus as well as a warning signal is output when SOC becomes critical. Through standard pin connectors and a simple I2C interface, the system can be used by many wireless devices (sensors) that have to run autonomously. After the presentation of this system, a focus on its application on a real use-case will be given. (orig.)

  15. Measurement of electron density profile by microwave reflectometry on tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Simonet, F.

    1985-05-01

    A new method for measuring the electron density spatial profile has been successfully tested on the tokamak of Fontenay aux Roses (TFR). This method is based on the total reflection experienced by a wave of frequency F on the layer where F = F/sub p/e(r). The experimental results show that the maximum electron density in the discharge is also easily measured and that accurate determination of a density profile can be obtained with a time resolution of 5 ms. This diagnostic is well adapted to all fusion devices where access to the total plasma cross section is limited, particularly for large tokamaks.

  16. Ionospheric topside models compared with experimental electron density profiles

    Directory of Open Access Journals (Sweden)

    S. M. Radicella

    2005-06-01

    Full Text Available Recently an increasing number of topside electron density profiles has been made available to the scientific community on the Internet. These data are important for ionospheric modeling purposes, since the experimental information on the electron density above the ionosphere maximum of ionization is very scarce. The present work compares NeQuick and IRI models with the topside electron density profiles available in the databases of the ISIS2, IK19 and Cosmos 1809 satellites. Experimental electron content from the F2 peak up to satellite height and electron densities at fixed heights above the peak have been compared under a wide range of different conditions. The analysis performed points out the behavior of the models and the improvements needed to be assessed to have a better reproduction of the experimental results. NeQuick topside is a modified Epstein layer, with thickness parameter determined by an empirical relation. It appears that its performance is strongly affected by this parameter, indicating the need for improvements of its formulation. IRI topside is based on Booker's approach to consider two parts with constant height gradients. It appears that this formulation leads to an overestimation of the electron density in the upper part of the profiles, and overestimation of TEC.

  17. Conductive Elastomers for Stretchable Electronics, Sensors and Energy Harvesters

    Directory of Open Access Journals (Sweden)

    Jin-Seo Noh

    2016-04-01

    Full Text Available There have been a wide variety of efforts to develop conductive elastomers that satisfy both mechanical stretchability and electrical conductivity, as a response to growing demands on stretchable and wearable devices. This article reviews the important progress in conductive elastomers made in three application fields of stretchable technology: stretchable electronics, stretchable sensors, and stretchable energy harvesters. Diverse combinations of insulating elastomers and non-stretchable conductive materials have been studied to realize optimal conductive elastomers. It is noted that similar material combinations and similar structures have often been employed in different fields of application. In terms of stretchability, cyclic operation, and overall performance, fields such as stretchable conductors and stretchable strain/pressure sensors have achieved great advancement, whereas other fields like stretchable memories and stretchable thermoelectric energy harvesting are in their infancy. It is worth mentioning that there are still obstacles to overcome for the further progress of stretchable technology in the respective fields, which include the simplification of material combination and device structure, securement of reproducibility and reliability, and the establishment of easy fabrication techniques. Through this review article, both the progress and obstacles associated with the respective stretchable technologies will be understood more clearly.

  18. Conference on Refrigeration for Cryogenic Sensors and Electronic Systems

    CERN Document Server

    Sullivan, D B; McCarthy, S E; Cryogenic Refrigeration Conference; International Cryocooler Conference; Cryocoolers 1

    1981-01-01

    This proceedings documents the output of a meeting of refrigeration specialists held at the National Bureau of Standards, Boulder, CO, on October 6 and 7, 1980. Building on an earlier invitation-only meeting in 1977, the purpose of this first open meeting was to discuss progress in the development of refrigeration systems to cool cryogenic sensors and electronic systems in the temperature range below 20 K and with required cooling capacities below 10 W. The meeting was jointly sponsored by the International Institute of Refrigeration - Commission A1/2, the Office of Naval Research, the Naval Research Laboratory, the Cryogenic Engineering Conference, and the National Bureau of Standards. This first open cryocooler conference consisted of 23 papers presented by representatives of industry, government, and academia. The conference proceedings reproduced here was published by the National Bureau of Standards in Boulder, Colorado as NBS Special Publication #607. Subsequent meetings would become known as the Intern...

  19. Gravitational Reference Sensor Front-End Electronics Simulator for LISA

    Science.gov (United States)

    Meshksar, Neda; Ferraioli, Luigi; Mance, Davor; ten Pierick, Jan; Zweifel, Peter; Giardini, Domenico; ">LISA Pathfinder colaboration, Electronics (FEE) for LISA Gravitational Reference Sensor (GRS). It is based on the GRS FEE-simulator already implemented for LISA Pathfinder. It considers, in particular, the non-linearity and the critical details of hardware, such as the non-linear multiplicative noise caused by voltage reference instability, test mass charging and detailed actuation and sensing algorithms. We present the simulation modules, considering the above-mentioned features. Based on the ETH GRS FEE-simulator for LISA Pathfinder we aim to develop a modular simulator that provides a realistic simulation of GRS FEE for LISA.

  20. Improving electronic sensor reliability by robust outlier screening.

    Science.gov (United States)

    Moreno-Lizaranzu, Manuel J; Cuesta, Federico

    2013-10-09

    Electronic sensors are widely used in different application areas, and in some of them, such as automotive or medical equipment, they must perform with an extremely low defect rate. Increasing reliability is paramount. Outlier detection algorithms are a key component in screening latent defects and decreasing the number of customer quality incidents (CQIs). This paper focuses on new spatial algorithms (Good Die in a Bad Cluster with Statistical Bins (GDBC SB) and Bad Bin in a Bad Cluster (BBBC)) and an advanced outlier screening method, called Robust Dynamic Part Averaging Testing (RDPAT), as well as two practical improvements, which significantly enhance existing algorithms. Those methods have been used in production in Freescale® Semiconductor probe factories around the world for several years. Moreover, a study was conducted with production data of 289,080 dice with 26 CQIs to determine and compare the efficiency and effectiveness of all these algorithms in identifying CQIs.

  1. Improving Electronic Sensor Reliability by Robust Outlier Screening

    Directory of Open Access Journals (Sweden)

    Federico Cuesta

    2013-10-01

    Full Text Available Electronic sensors are widely used in different application areas, and in some of them, such as automotive or medical equipment, they must perform with an extremely low defect rate. Increasing reliability is paramount. Outlier detection algorithms are a key component in screening latent defects and decreasing the number of customer quality incidents (CQIs. This paper focuses on new spatial algorithms (Good Die in a Bad Cluster with Statistical Bins (GDBC SB and Bad Bin in a Bad Cluster (BBBC and an advanced outlier screening method, called Robust Dynamic Part Averaging Testing (RDPAT, as well as two practical improvements, which significantly enhance existing algorithms. Those methods have been used in production in Freescale® Semiconductor probe factories around the world for several years. Moreover, a study was conducted with production data of 289,080 dice with 26 CQIs to determine and compare the efficiency and effectiveness of all these algorithms in identifying CQIs.

  2. Beam Profile Diagnostics for the Fermilab Medium Energy Electron Cooler

    Science.gov (United States)

    Warner, A.; Kazakevich, G.; Nagaitsev, S.; Tassotto, G.; Gai, W.; Konecny, R.

    2005-10-01

    The Fermilab Recycler ring will employ an electron cooler to store and cool 8.9 GeV antiprotons. The cooler will be based on a Pelletron electrostatic accelerator working in an energy-recovery regime. Several techniques for determining the characteristics of the beam dynamics are being investigated. Beam profiles have been measured as a function of the beam line optics at the energy of 3.5 MeV in the current range of 10/sup -4/-1 A, with a pulse duration of 2 /spl mu/s. The profiles were measured using optical transition radiation produced at the interface of a 250-/spl mu/m aluminum foil and also from YAG crystal luminescence. In addition, beam profiles measured using multiwire detectors were investigated. These three diagnostics will be used together to determine the profile dynamics of the beam. In this paper we report the results so far obtained using these techniques.

  3. Assisted editing od SensorML with EDI. A bottom-up scenario towards the definition of sensor profiles.

    Science.gov (United States)

    Oggioni, Alessandro; Tagliolato, Paolo; Fugazza, Cristiano; Bastianini, Mauro; Pavesi, Fabio; Pepe, Monica; Menegon, Stefano; Basoni, Anna; Carrara, Paola

    2015-04-01

    -product of this ongoing work is currently constituting an archive of predefined sensor descriptions. This information is being collected in order to further ease metadata creation in the next phase of the project. Users will be able to choose among a number of sensor and sensor platform prototypes: These will be specific instances on which it will be possible to define, in a bottom-up approach, "sensor profiles". We report on the outcome of this activity.

  4. Molecular modeling of polymer composite-analyte interactions in electronic nose sensors

    Science.gov (United States)

    Shevade, A. V.; Ryan, M. A.; Homer, M. L.; Manfreda, A. M.; Zhou, H.; Manatt, K. S.

    2003-01-01

    We report a molecular modeling study to investigate the polymer-carbon black (CB) composite-analyte interactions in resistive sensors. These sensors comprise the JPL electronic nose (ENose) sensing array developed for monitoring breathing air in human habitats. The polymer in the composite is modeled based on its stereoisomerism and sequence isomerism, while the CB is modeled as uncharged naphthalene rings with no hydrogens. The Dreiding 2.21 force field is used for the polymer, solvent molecules and graphite parameters are assigned to the carbon black atoms. A combination of molecular mechanics (MM) and molecular dynamics (NPT-MD and NVT-MD) techniques are used to obtain the equilibrium composite structure by inserting naphthalene rings in the polymer matrix. Polymers considered for this work include poly(4-vinylphenol), polyethylene oxide, and ethyl cellulose. Analytes studied are representative of both inorganic and organic compounds. The results are analyzed for the composite microstructure by calculating the radial distribution profiles as well as for the sensor response by predicting the interaction energies of the analytes with the composites. c2003 Elsevier Science B.V. All rights reserved.

  5. Driver behavior profiling: An investigation with different smartphone sensors and machine learning.

    Directory of Open Access Journals (Sweden)

    Jair Ferreira

    Full Text Available Driver behavior impacts traffic safety, fuel/energy consumption and gas emissions. Driver behavior profiling tries to understand and positively impact driver behavior. Usually driver behavior profiling tasks involve automated collection of driving data and application of computer models to generate a classification that characterizes the driver aggressiveness profile. Different sensors and classification methods have been employed in this task, however, low-cost solutions and high performance are still research targets. This paper presents an investigation with different Android smartphone sensors, and classification algorithms in order to assess which sensor/method assembly enables classification with higher performance. The results show that specific combinations of sensors and intelligent methods allow classification performance improvement.

  6. Encapsulation for smart textile electronics - humidity and temperature sensor.

    Science.gov (United States)

    Larsson, Andreas; Tran, Thanh-Nam; Aasmundtveit, Knut E; Seeberg, Trine M

    2015-01-01

    A combined humidity and temperature sensor was packaged by vacuum casting onto three different types of textiles; cotton, nylon and a waterproof fabric. This was done in order to integrate the sensor in a jacket in a soft and reliable way without changing the sensor performance. A membrane was custom made and integrated into the device to protect the sensor from the environment. The packaged sensors performance was characterized in a climate chamber were the relative humidity and temperature ranged from 25 % to 95 % and -10 °C to 75 °C respectively. The packaged sensors showed insignificant to limited performance degradation.

  7. Chloride ingress profiles measured by electron probe micro analysis

    DEFF Research Database (Denmark)

    Jensen, Ole mejlhede; Coats, Alison M.; Glasser, Fred P.

    1996-01-01

    Traditional techniques for measuring chloride ingress profiles do not apply well to high performance cement paste systems; the geometric resolution of the traditional measuring techniques is too low. In this paper measurements by Electron Probe Micro Analysis (EPMA) are presented. EPMA...... is demonstated to determine chloride ingress in cement paste on a micrometer scale. Potential chloride ingress routes such as cracks or the paste-aggregate interface may also be characterized by EPMA. Copyright (C) 1996 Elsevier Science Ltd...

  8. Antiproton beam profile measurements using Gas Electron Multipliers

    CERN Document Server

    Duarte Pinto, Serge; Spanggaard, Jens; Tranquille, Gerard

    2011-01-01

    The new beam profile measurement for the Antiproton Decelerator (AD) at CERN is based on a single Gas Electron Multiplier (GEM) with a 2D readout structure. This detector is very light, ~0.4% X_0, as required by the low energy of the antiprotons, 5.3 MeV. This overcomes the problems previously encountered with multi-wire proportional chambers (MWPC) for the same purpose, where beam interactions with the detector severely affect the obtained profiles. A prototype was installed and successfully tested in late 2010, with another five detectors now installed in the ASACUSA and AEgIS beam lines. We will provide a detailed description of the detector and discuss the results obtained. The success of these detectors in the AD makes GEM-based detectors likely candidates for upgrade of the beam profile monitors in all experimental areas at CERN. The various types of MWPC currently in use are aging and becoming increasingly difficult to maintain.

  9. Magnetoresistive Current Sensors for High Accuracy, High Bandwidth Current Measurement in Spacecraft Power Electronics

    Science.gov (United States)

    Slatter, Rolf; Goffin, Benoit

    2014-08-01

    The usage of magnetoresistive (MR) current sensors is increasing steadily in the field of power electronics. Current sensors must not only be accurate and dynamic, but must also be compact and robust. The MR effect is the basis for current sensors with a unique combination of precision and bandwidth in a compact package. A space-qualifiable magnetoresistive current sensor with high accuracy and high bandwidth is being jointly developed by the sensor manufacturer Sensitec and the spacecraft power electronics supplier Thales Alenia Space (T AS) Belgium. Test results for breadboards incorporating commercial-off-the-shelf (COTS) sensors are presented as well as an application example in the electronic control and power unit for the thrust vector actuators of the Ariane5-ME launcher.

  10. An All-Elastomeric Transparent and Stretchable Temperature Sensor for Body-Attachable Wearable Electronics.

    Science.gov (United States)

    Trung, Tran Quang; Ramasundaram, Subramaniyan; Hwang, Byeong-Ung; Lee, Nae-Eung

    2016-01-20

    A transparent stretchable (TS) gated sensor array with high optical transparency, conformality, and high stretchability of up to 70% is demonstrated. The TS-gated sensor array has high responsivity to temperature changes in objects and human skin. This unprecedented TS-gated sensor array, as well as the integrated platform of the TS-gated sensor with a transparent and stretchable strain sensor, show great potential for application to wearable skin electronics for recognition of human activity. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Validation of Ocean Color Sensors Using a Profiling Hyperspectral Radiometer

    Science.gov (United States)

    2014-01-01

    acknowledge the help of MOBY Team members. Especially Stephanie Flora from Moss Landing Marine Labs and Carol Johnson from NIST for calibration support. We...Mississippi, MS 39529 "" MOSS Landing Marine Laboratory, Honolulu, HI ABSTRACT Validation measurements of satellite ocean color sensors require in situ...McLean, S., Lewis, M., Johnson, C, Flora , S., Feinholz, M., Yarbrough, M., Trees, C, Twardowski, M., and Clark, D., "An Example Crossover Experiment

  12. Numerical calibration of laser line scanning system with multiple sensors for inspecting cross-section profiles

    Science.gov (United States)

    Zhou, Jingbo; Li, Yuehua; Huang, Fengshan; Liu, Lijian

    2016-11-01

    Line structured light sensors (LSLSs) have gained more and more applications in industry. An interested profile can be easily obtained through the analysis of laser-object intersection stripe. But one sensor is inadequate to get a closed crosssection profile due to the obstacle of the laser light. Thus, multiple LSLSs were integrated as a whole for profile inspection and a numerical calibration method was also proposed. Firstly, the laser planes from all laser projectors were adjusted to coincide with the target plane by adjusting the fixtures of the laser projector. For each sensor, origin of the world coordinate system (WCS) was fixed at the center of a corner calibration dot with its X and Y axis coincide with the row and column direction of target dots. Each sensor camera captured one image of the same target. The relationship between the pixel coordinate system (PCS) and the WCS was established using an interpolation method via the world coordinates of target dot centers and their corresponding pixel coordinates. Then the measurement points from all the sensors were transformed into the global WCS, and a closed cross-section profile can be achieved. This proposed method neither need to establish the intrinsic, the extrinsic and the distortion models of the camera, nor need to solve the complex optimization equations to determine the model coefficients. Finally, a workpeice with stairs and a rectangular block were inspected. The comparison with the measuring results from the coordinate measuring machine further validates the high accuracy of the proposed method.

  13. [Prevalence and user profile of electronic cigarettes in Spain (2014)].

    Science.gov (United States)

    Lidón-Moyano, Cristina; Martínez-Sánchez, Jose M; Fu, Marcela; Ballbè, Montse; Martín-Sánchez, Juan Carlos; Fernández, Esteve

    To describe the prevalence and user profile of electronic cigarettes among Spanish adults and evaluate the potential dual use of these devices with combustible or conventional tobacco in 2014 in Spain. Cross-sectional study of a representative sample of the Spanish adult (16-75 years old) population (n=1,016). A computer-assisted telephone survey was conducted in 2014. The prevalence and 95% confidence intervals (95% CI) for the use of electronic cigarettes stratified by gender, age, tobacco consumption and social status were calculated. The sample was weighted and a logistic regression model adjusted to obtain the crude odds ratios (OR) adjusted by gender, age and social status. 10.3% (95% CI: 8.6-12.4) of the Spanish adult population stated being ever users of electronic cigarettes (2% current users, 3.2% past users and 5.1% experimental users). Among current electronic cigarette users, 57.2% also smoked combustible or conventional tobacco, 28% had never smoked and 14.8% were former smokers. The prevalence of electronic cigarette use was higher in the younger population (adjusted OR=23.8; 95% CI: 2.5-227.7) and smokers of combustible tobacco (adjusted OR=10.1; 95% CI: 5.8-17.5). The use of electronic cigarettes in Spain is scarce and is most prevalent among young people and tobacco smokers. Nevertheless, one out of four current electronic cigarette users have never smoked. Hence, the regulation of these devices should be reinforced to avoid a possible gateway to nicotine products among never smokers. Copyright © 2016 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.

  14. Electron Beam Profiler for the Fermilab Main Injector

    Energy Technology Data Exchange (ETDEWEB)

    Thurman-Keup, R. [Fermilab; Alvarez, M [Fermilab; Fitzgerald, J. [Fermilab; Lundberg, C. [Fermilab; Prieto, P. [Fermilab; Blokland, W. [ORNL, Oak Ridge

    2014-01-01

    The long range plan for Fermilab calls for large proton beam intensities in excess of 2 MW for use in the neutrino program. Measuring the transverse profiles of these high intensity beams is challenging and generally relies on non-invasive techniques. One such technique involves measuring the deflection of a beam of electrons with a trajectory perpendicular to the proton beam. A device such as this is already in use at the Spallation Neutron Source at ORNL and a similar device will be installed shortly in the Fermilab Main Injector. The Main Injector device is discussed in detail and some test results and simulations are shown

  15. Optical and Electronic NOx Sensors for Applications in Mechatronics

    Science.gov (United States)

    Di Franco, Cinzia; Elia, Angela; Spagnolo, Vincenzo; Scamarcio, Gaetano; Lugarà, Pietro Mario; Ieva, Eliana; Cioffi, Nicola; Torsi, Luisa; Bruno, Giovanni; Losurdo, Maria; Garcia, Michael A.; Wolter, Scott D.; Brown, April; Ricco, Mario

    2009-01-01

    Current production and emerging NOx sensors based on optical and nanomaterials technologies are reviewed. In view of their potential applications in mechatronics, we compared the performance of: i) Quantum cascade lasers (QCL) based photoacoustic (PA) systems; ii) gold nanoparticles as catalytically active materials in field-effect transistor (FET) sensors, and iii) functionalized III-V semiconductor based devices. QCL-based PA sensors for NOx show a detection limit in the sub part-per-million range and are characterized by high selectivity and compact set-up. Electrochemically synthesized gold-nanoparticle FET sensors are able to monitor NOx in a concentration range from 50 to 200 parts per million and are suitable for miniaturization. Porphyrin-functionalized III-V semiconductor materials can be used for the fabrication of a reliable NOx sensor platform characterized by high conductivity, corrosion resistance, and strong surface state coupling. PMID:22412315

  16. STRETCHY ELECTRONICS. Hierarchically buckled sheath-core fibers for superelastic electronics, sensors, and muscles.

    Science.gov (United States)

    Liu, Z F; Fang, S; Moura, F A; Ding, J N; Jiang, N; Di, J; Zhang, M; Lepró, X; Galvão, D S; Haines, C S; Yuan, N Y; Yin, S G; Lee, D W; Wang, R; Wang, H Y; Lv, W; Dong, C; Zhang, R C; Chen, M J; Yin, Q; Chong, Y T; Zhang, R; Wang, X; Lima, M D; Ovalle-Robles, R; Qian, D; Lu, H; Baughman, R H

    2015-07-24

    Superelastic conducting fibers with improved properties and functionalities are needed for diverse applications. Here we report the fabrication of highly stretchable (up to 1320%) sheath-core conducting fibers created by wrapping carbon nanotube sheets oriented in the fiber direction on stretched rubber fiber cores. The resulting structure exhibited distinct short- and long-period sheath buckling that occurred reversibly out of phase in the axial and belt directions, enabling a resistance change of less than 5% for a 1000% stretch. By including other rubber and carbon nanotube sheath layers, we demonstrated strain sensors generating an 860% capacitance change and electrically powered torsional muscles operating reversibly by a coupled tension-to-torsion actuation mechanism. Using theory, we quantitatively explain the complementary effects of an increase in muscle length and a large positive Poisson's ratio on torsional actuation and electronic properties. Copyright © 2015, American Association for the Advancement of Science.

  17. Low-gradient single-sided NMR sensor for one-shot profiling of human skin.

    Science.gov (United States)

    Van Landeghem, Maxime; Danieli, Ernesto; Perlo, Juan; Blümich, Bernhard; Casanova, Federico

    2012-02-01

    This paper describes a shimming approach useful to reduce the gradient strength of the magnetic field generated by single-sided sensors simultaneously maximizing its uniformity along the lateral directions of the magnet. In this way, the thickness of the excited sensitive volume can be increased without compromising the depth resolution of the sensor. By implementing this method on a standard U-shaped magnet, the gradient strength was reduced one order of magnitude. In the presence of a gradient of about 2 T/m, slices of 2mm could be profiled with a resolution that ranges from 25 μm at the center of the slice to 50 μm at the borders. This sensor is of particular advantage for applications, where the scanning range is of the order of the excited slice. In those cases, the full profile is measured in a single excitation experiment, eliminating the need for repositioning the excited slice across the depth range to complete the profile as occurs with standard high gradient sensors. Besides simplifying the experimental setup, the possibility to move from a point-by-point measurement to the simultaneous acquisition of the full profile led to the shortening of the experimental time. A further advantage of performing the experiment under a smaller static gradient is a reduction of the diffusion attenuation affecting the signal decay measured with a CPMG sequence, making it possible to measure the T(2) of samples with high diffusivity (comparable to the water diffusivity). The performance of the sensor in terms of resolution and sensitivity is first evaluated and compared with conventional singled-sided sensors of higher gradient strength using phantoms of known geometry and relaxation times. Then, the device is used to profile the structure of human skin in vivo. To understand the contrast between the different skin layers, the distribution of relaxation times T(2) and diffusion coefficients is spatially resolved along the depth direction. Copyright © 2011 Elsevier Inc

  18. Learning Laboratory Chemistry through Electronic Sensors, a Microprocessor, and Student Enabling Software: A Preliminary Demonstration

    Science.gov (United States)

    Zhang, Qing; Brode, Ly; Cao, Tingting; Thompson, J. E.

    2017-01-01

    We describe the construction and initial demonstration of a new instructional tool called ROXI (Research Opportunity through eXperimental Instruction). The system interfaces a series of electronic sensors to control software via the Arduino platform. The sensors have been designed to enable low-cost data collection in laboratory courses. Data are…

  19. Metal–Organic Frameworks as Active Materials in Electronic Sensor Devices

    Science.gov (United States)

    Campbell, Michael G.; Dincă, Mircea

    2017-01-01

    In the past decade, advances in electrically conductive metal–organic frameworks (MOFs) and MOF-based electronic devices have created new opportunities for the development of next-generation sensors. Here we review this rapidly-growing field, with a focus on the different types of device configurations that have allowed for the use of MOFs as active components of electronic sensor devices. PMID:28498308

  20. New results on diamond pixel sensors using ATLAS frontend electronics

    CERN Document Server

    Keil, Markus; Berdermann, E; Bergonzo, P; de Boer, Wim; Bogani, F; Borchi, E; Brambilla, A; Bruzzi, Mara; Colledani, C; Conway, J; D'Angelo, P; Dabrowski, W; Delpierre, P A; Dulinski, W

    2003-01-01

    Diamond is a promising sensor material for future collider experiments due to its radiation hardness. Diamond pixel sensors have been bump bonded to an ATLAS pixel readout chip using PbSn solder bumps. Single chip devices have been characterised by lab measurements and in a high-energy pion beam at CERN. Results on charge collection, spatial resolution, efficiency and the charge carrier lifetime are presented.

  1. A novel low profile wireless flow sensor to monitor hemodynamic changes in cerebral aneurysm

    Science.gov (United States)

    Chen, Yanfei; Jankowitz, Brian T.; Cho, Sung Kwon; Chun, Youngjae

    2015-03-01

    A proof of concept of low-profile flow sensor has been designed, fabricated, and subsequently tested to demonstrate its feasibility for monitoring hemodynamic changes in cerebral aneurysm. The prototype sensor contains three layers, i.e., a thin polyurethane layer was sandwiched between two sputter-deposited thin film nitinol layers (6μm thick). A novel superhydrophilic surface treatment was used to create hemocompatible surface of thin nitinol electrode layers. A finite element model was conducted using ANSYS Workbench 15.0 Static Structural to optimize the dimensions of flow sensor. A computational fluid dynamics calculations were performed using ANSYS Workbench Fluent to assess the flow velocity patterns within the aneurysm sac. We built a test platform with a z-axis translation stage and an S-beam load cell to compare the capacitance changes of the sensors with different parameters during deformation. Both LCR meter and oscilloscope were used to measure the capacitance and the resonant frequency shifts, respectively. The experimental compression tests demonstrated the linear relationship between the capacitance and applied compression force and decreasing the length, width and increasing the thickness improved the sensor sensitivity. The experimentally measured resonant frequency dropped from 12.7MHz to 12.48MHz, indicating a 0.22MHz shift with 200g ( 2N) compression force while the theoretical resonant frequency shifted 0.35MHz with 50g ( 0.5N). Our recent results demonstrated a feasibility of the low-profile flow sensor for monitoring haemodynamics in cerebral aneurysm region, as well as the efficacy of the use of the surface treated thin film nitinol for the low-profile sensor materials.

  2. A High-Speed CMOS Image Sensor with Global Electronic Shutter Pixels Using Pinned Diodes

    Science.gov (United States)

    Yasutomi, Keita; Tamura, Toshihiro; Furuta, Masanori; Itoh, Shinya; Kawahito, Shoji

    This paper describes a high-speed CMOS image sensor with a new type of global electronic shutter pixel. A global electronic shutter is necessary for imaging fast-moving objects without motion blur or distortion. The proposed pixel has two potential wells with pinned diode structure for two-stage charge transfer that enables a global electronic shuttering and reset noise canceling. A prototype high-speed image sensor fabricated in 0.18μm standard CMOS image sensor process consists of the proposed pixel array, 12-bit column-parallel cyclic ADC arrays and 192-channel digital outputs. The sensor achieves a good linearity at low-light intensity, demonstrating the perfect charge transfer between two pinned diodes. The input referred noise of the proposed pixel is measured to be 6.3 e-.

  3. Functional nanomaterials and devices for electronics, sensors and energy harvesting

    CERN Document Server

    Balestra, Francis; Kilchytska, Valeriya; Flandre, Denis

    2014-01-01

    This book contains reviews of recent experimental and theoretical results related to nanomaterials. It focuses on novel functional materials and nanostructures in combination with silicon on insulator (SOI) devices, as well as on the physics of new devices and sensors, nanostructured materials and nano scaled device characterization. Special attention is paid to fabrication and properties of modern low-power, high-performance, miniaturized, portable sensors in a wide range of applications such as telecommunications, radiation control, biomedical instrumentation and chemical analysis. In this book, new approaches exploiting nanotechnologies (such as UTBB FD SOI, Fin FETs, nanowires, graphene or carbon nanotubes on dielectric) to pave a way between “More Moore” and “More than Moore” are considered, in order to create different kinds of sensors and devices which will consume less electrical power, be more portable and totally compatible with modern microelectronics products.

  4. Effects of electron beam irradiation on tin dioxide gas sensors

    Indian Academy of Sciences (India)

    WINTEC

    Abstract. In this paper, the effects of electron beam irradiation on the gas sensing performance of tin dioxide thin films toward H2 are studied. The tin dioxide thin films were prepared by ultrasonic spray pyrolysis. The results show that the sensitivity increased after electron beam irradiation. The electron beam irradiation.

  5. Profile Monitors for Wide Multiplicity Range Electron Beams

    CERN Document Server

    Buonomo, B; Quintieri, L

    2005-01-01

    The DAFNE Beam Test Facility (BTF) provides electron and positron beams in a wide range of intensity, from single particle up to 1010 particles per pulse, and energy, from a few tens of MeV up to 800 MeV. The pulse time width can be adjusted between 1 and 10 ns and the maximum repetition rate is 50 Hz. The large range of operation of the facility requires the implementation of different beam profile and multiplicity monitors. In the single particle operation mode the beam spot profile and position are measured by a x-y scintillating fiber system with millimetric resolution and multi-anode PMT readout. From a few tens up to 106-107 particles per pulse, a silicon chamber made of two 9.5x9.5 cm2 wide 400μm thick silicon strip detectors organized in a x-y configuration with a pitch of 121μm has been developed. Once calibrated, the system can be used also as an intensity monitor. The description of the devices and the results obtained during the data taking periods of several experiments at the...

  6. Touch mode micromachined capacitive pressure sensor with signal conditioning electronics

    DEFF Research Database (Denmark)

    Fragiacomo, Giulio; Eriksen, Gert F.; Christensen, Carsten

    2010-01-01

    technology to design and fabricate these sensors has been implemented. Capacitive pressure sensing, on the other hand, is still an open and really promising field. Results Capacitive microsensors were designed and fabricated (Fig. 1) and an analytical model for touch mode regime, which fitted accurately...

  7. Organic electronics based pressure sensor towards intracranial pressure monitoring

    Science.gov (United States)

    Rai, Pratyush; Varadan, Vijay K.

    2010-04-01

    The intra-cranial space, which houses the brain, contains cerebrospinal fluid (CSF) that acts as a fluid suspension medium for the brain. The CSF is always in circulation, is secreted in the cranium and is drained out through ducts called epidural veins. The venous drainage system has inherent resistance to the flow. Pressure is developed inside the cranium, which is similar to a rigid compartment. Normally a pressure of 5-15 mm Hg, in excess of atmospheric pressure, is observed at different locations inside the cranium. Increase in Intra-Cranial Pressure (ICP) can be caused by change in CSF volume caused by cerebral tumors, meningitis, by edema of a head injury or diseases related to cerebral atrophy. Hence, efficient ways of monitoring ICP need to be developed. A sensor system and monitoring scheme has been discussed here. The system architecture consists of a membrane less piezoelectric pressure sensitive element, organic thin film transistor (OTFT) based signal transduction, and signal telemetry. The components were fabricated on flexible substrate and have been assembled using flip-chip packaging technology. Material science and fabrication processes, subjective to the device performance, have been discussed. Capability of the device in detecting pressure variation, within the ICP pressure range, is investigated and applicability of measurement scheme to medical conditions has been argued for. Also, applications of such a sensor-OTFT assembly for logic sensor switching and patient specific-secure monitoring system have been discussed.

  8. Creating Diversified Response Profiles from a Single Quenchometric Sensor Element by Using Phase-Resolved Luminescence

    Directory of Open Access Journals (Sweden)

    Elizabeth C. Tehan

    2015-01-01

    Full Text Available We report a new strategy for generating a continuum of response profiles from a single luminescence-based sensor element by using phase-resolved detection. This strategy yields reliable responses that depend in a predictable manner on changes in the luminescent reporter lifetime in the presence of the target analyte, the excitation modulation frequency, and the detector (lock-in amplifier phase angle. In the traditional steady-state mode, the sensor that we evaluate exhibits a linear, positive going response to changes in the target analyte concentration. Under phase-resolved conditions the analyte-dependent response profiles: (i can become highly non-linear; (ii yield negative going responses; (iii can be biphasic; and (iv can exhibit super sensitivity (e.g., sensitivities up to 300 fold greater in comparison to steady-state conditions.

  9. Temporal and spatial variations in ionospheric electron density profiles over South Africa during strong magnetic storms

    National Research Council Canada - National Science Library

    Yao, Y. B; Chen, P; Zhang, S; Chen, J. J

    2013-01-01

    ...) and vertical total electron content (VTEC) data from the Jason-1 satellite were used to analyze the variations in ionospheric electron density profiles over South Africa before and after the severe geomagnetic storms on 15 May 2005...

  10. Packaging Technology Developed for High-Temperature SiC Sensors and Electronics

    Science.gov (United States)

    Chen, Liang-Yu; Hunter, Gary W.; Neudeck, Philip G.; Lei, Jih-Fen

    2000-01-01

    A ceramic- and thick-film-materials-based prototype electronic package designed for silicon carbide (SiC) high-temperature sensors and electronics has been successfully tested at 500 C in an oxygen-containing air environment for 500 hours. This package was designed, fabricated, assembled, and electronically evaluated at the NASA Glenn Research Center at Lewis Field with an in-house-fabricated SiC semiconductor test chip. High-temperature electronics and sensors are necessary for harsh-environment space and aeronautical applications, such as space missions to the inner solar system or the emission control electronics and sensors in aeronautical engines. Single-crystal SiC has such excellent physical and chemical material properties that SiC-based semiconductor electronics can operate at temperatures over 600 C, which is significantly higher than the limit for Si-based semiconductor devices. SiC semiconductor chips were recently demonstrated to be operable at temperatures as high as 600 C, but only in the probe station environment because suitable packaging technology for sensors and electronics at temperatures of 500 C and beyond did not exist. Thus, packaging technology for SiC-based sensors and electronics is immediately needed for both application and commercialization of high-temperature SiC sensors and electronics. In response to this need, researchers at Glenn designed, fabricated, and assembled a prototype electronic package for high-temperature electronics, sensors, and microelectromechanical systems (MEMS) using aluminum nitride (AlN) substrate and gold (Au) thick-film materials. This prototype package successfully survived a soak test at 500 C in air for 500 hours. Packaging components tested included thick-film high-temperature metallization, internal wire bonds, external lead bonds, and a SiC diode chip die-attachment. Each test loop, which was composed of thick-film printed wire, wire bond, and lead bond was subjected to a 50-mA direct current for 250

  11. Investigation of the radiation hardness of GaAs sensors in an electron beam

    CERN Document Server

    K. Afanaciev, K; P. Bernitt, P; G. Chelkov, G; J. Gajewski, J; M. Gostkin, M; Ch Grah, Ch; R. Heller, R; H. Henschel, H; A. Ignatenko, A; Z. Krumshteyn, Z; S. Kulis, S; W. Lange, W; W. Lohmann, W; D. Mokeev, D; V. Novikov, V; M. Ohlerich, M; A. Rosca, A; A. Sapronov, A; R.S. Schmidt, R S; S. Schuwalow, S; O. Tolbanov, O; A. Tyazhev, A

    2012-01-01

    A compact and finely grained sandwich calorimeter is designed to instrument the very forward region of a detector at a future e+e− collider. The calorimeter will be exposed to low energy e+e− pairs originating from beamstrahlung, resulting in absorbed doses of about one MGy per year. GaAs pad sensors interleaved with tungsten absorber plates are considered as an option for this calorimeter. Several Cr-doped GaAs sensor prototypes were produced and irradiated with 8.5–10 MeV electrons up to a dose of 1.5 MGy. The sensor performance was measured as a function of the absorbed dose.

  12. Shape and Current Profile Effects on Runaway Electron Confinement

    Science.gov (United States)

    Izzo, V. A.; James, A. N.; Humphreys, D. A.; Granetz, R. S.; Whyte, D. G.; Olynyk, G. M.

    2011-10-01

    The potential for several MA of current carried by multi-MeV runaway electrons (REs) during ITER disruptions has motivated a variety of experiments in present-day tokamaks studying RE generation, confinement, and control. In both DIII-D and Alcator C Mod, different RE behavior is seen in limited vs. diverted plasmas, suggesting better RE confinement for limited shapes. NIMROD simulations of rapid shutdowns in both devices support this finding, and show reduced stochasticity in limited plasma shapes. Integration of RE drift-orbits also shows differences in RE strike-points that are consistent with experimental observations. In DIII-D a wide variation in RE confinement results for diverted discharges may also point to current density profile effects on RE confinement. Several DIII-D diverted discharges are modeled with NIMROD. Confined RE fractions found in NIMROD are mostly consistent with observed RE currents in DIII-D, although other effects, such as seed generation and avalanching may contribute to the experimental variation. Work supported by US DOE under DE-FC02-06ER54861, DE-FG02-05ER54809, DE-FG02-07ER54917, DE-FC02-04ER54698 and DE-FG02-04ER54762.

  13. Development of Fabric-Based Chemical Gas Sensors for Use as Wearable Electronic Noses

    Directory of Open Access Journals (Sweden)

    Thara Seesaard

    2015-01-01

    Full Text Available Novel gas sensors embroidered into fabric substrates based on polymers/ SWNT-COOH nanocomposites were proposed in this paper, aiming for their use as a wearable electronic nose (e-nose. The fabric-based chemical gas sensors were fabricated by two main processes: drop coating and embroidery. Four potential polymers (PVC, cumene-PSMA, PSE and PVP/functionalized-SWCNT sensing materials were deposited onto interdigitated electrodes previously prepared by embroidering conductive thread on a fabric substrate to make an optimal set of sensors. After preliminary trials of the obtained sensors, it was found that the sensors yielded a electrical resistance in the region of a few kilo-Ohms. The sensors were tested with various volatile compounds such as ammonium hydroxide, ethanol, pyridine, triethylamine, methanol and acetone, which are commonly found in the wastes released from the human body. These sensors were used to detect and discriminate between the body odors of different regions and exist in various forms such as the urine, armpit and exhaled breath odor. Based on a simple pattern recognition technique, we have shown that the proposed fabric-based chemical gas sensors can discriminate the human body odor from two persons.

  14. A Self-Healing Electronic Sensor Based on Thermal-Sensitive Fluids.

    Science.gov (United States)

    He, Yonglin; Liao, Shenglong; Jia, Hanyu; Cao, Yuanyuan; Wang, Zhenning; Wang, Yapei

    2015-08-19

    A combination of liquid sensing materials and self-healing polymers is conceived for preparing electronic sensors that can be mended when they suffer damage. The leakage of ionic liquids at a breaking state is avoided with the help of the capillary effect. Photothermal conversion and magnetic-thermal conversion extend the sensing application. The successful development of self-healing sensors is promising for exploiting high-level electronic devices with long-term service. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. An Electronic-Nose Sensor Node Based on a Polymer-Coated Surface Acoustic Wave Array for Wireless Sensor Network Applications

    Directory of Open Access Journals (Sweden)

    Kea-Tiong Tang

    2011-04-01

    Full Text Available This study developed an electronic-nose sensor node based on a polymer-coated surface acoustic wave (SAW sensor array. The sensor node comprised an SAW sensor array, a frequency readout circuit, and an Octopus II wireless module. The sensor array was fabricated on a large K2 128° YX LiNbO3 sensing substrate. On the surface of this substrate, an interdigital transducer (IDT was produced with a Cr/Au film as its metallic structure. A mixed-mode frequency readout application specific integrated circuit (ASIC was fabricated using a TSMC 0.18 μm process. The ASIC output was connected to a wireless module to transmit sensor data to a base station for data storage and analysis. This sensor node is applicable for wireless sensor network (WSN applications.

  16. An electronic-nose sensor node based on a polymer-coated surface acoustic wave array for wireless sensor network applications.

    Science.gov (United States)

    Tang, Kea-Tiong; Li, Cheng-Han; Chiu, Shih-Wen

    2011-01-01

    This study developed an electronic-nose sensor node based on a polymer-coated surface acoustic wave (SAW) sensor array. The sensor node comprised an SAW sensor array, a frequency readout circuit, and an Octopus II wireless module. The sensor array was fabricated on a large K(2) 128° YX LiNbO3 sensing substrate. On the surface of this substrate, an interdigital transducer (IDT) was produced with a Cr/Au film as its metallic structure. A mixed-mode frequency readout application specific integrated circuit (ASIC) was fabricated using a TSMC 0.18 μm process. The ASIC output was connected to a wireless module to transmit sensor data to a base station for data storage and analysis. This sensor node is applicable for wireless sensor network (WSN) applications.

  17. Assessment studies on the inversion of satellite to satellite electron content to obtain electron density profiles in the ionosphere

    CERN Document Server

    Hochegger, G P

    2000-01-01

    The electron content data, obtained by satellite-to-satellite occultations of radio signals can lead to height profiles of electron density by discrete inversion. Since there is no possibility to verify such profiles by means of other measurements (practically never measurements at the same time and same location) it was necessary to simulate occultation scenarios by means of an ionosphere model to obtain a large number of comparisons sufficient for investigations on a statistical basis. The obtained electron contents were inverted and compared with electron density height profiles, obtained with the same ionospheric model for the occultation point. The differences between these profiles were investigated (difference between the F2-peak maxima, the height of the maxima, the shape of the topside and bottom side ionosphere). Since simulations were done for chosen locations (250 randomly spread on the globe) for every month and every second hour and for two solar activity levels (HSA and LSA), a whole year was '...

  18. Radiation damage studies on STAR250 CMOS sensor at 300 keV for electron microscopy

    Science.gov (United States)

    Faruqi, A. R.; Henderson, R.; Holmes, J.

    2006-09-01

    There is a pressing need for better electronic detectors to replace film for recording high-resolution images using electron cryomicroscopy. Our previous work has shown that direct electron detection in CMOS sensors is promising in terms of resolution and efficiency at 120 keV [A.R. Faruqi, R. Henderson, M. Prydderch, R. Turchetta, P. Allport, A. Evans, Nucl. Instr. and Meth. 546 (2005) 170], but in addition, the detectors must not be damaged by the electron irradiation. We now present new measurements on the radiation tolerance of a 25 μm pitch CMOS active-pixel sensor, the STAR250, which was designed by FillFactory using radiation-hard technology for space applications. Our tests on the STAR250 aimed to establish the imaging performance at 300 keV following irradiation. The residual contrast, measured on shadow images of a 300 mesh grid, was >80% after corrections for increased dark current, following irradiation with up to 5×10 7 electrons/pixel (equivalent to 80,000 electron/μm 2). A CMOS sensor with this degree of radiation tolerance would survive a year of normal usage for low-dose electron cryomicroscopy, which is a very useful advance.

  19. Radiation damage studies on STAR250 CMOS sensor at 300 keV for electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Faruqi, A.R. [MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH (United Kingdom)]. E-mail: arf@mrc-lmb.cam.ac.uk; Henderson, R. [MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH (United Kingdom); Holmes, J. [Sira Technology Ltd., South Hill, Chislehurst, Kent BR7 5EH (United Kingdom)

    2006-09-01

    There is a pressing need for better electronic detectors to replace film for recording high-resolution images using electron cryomicroscopy. Our previous work has shown that direct electron detection in CMOS sensors is promising in terms of resolution and efficiency at 120 keV [A.R. Faruqi, R. Henderson, M. Prydderch, R. Turchetta, P. Allport, A. Evans, Nucl. Instr. and Meth. 546 (2005) 170], but in addition, the detectors must not be damaged by the electron irradiation. We now present new measurements on the radiation tolerance of a 25 {mu}m pitch CMOS active-pixel sensor, the STAR250, which was designed by FillFactory using radiation-hard technology for space applications. Our tests on the STAR250 aimed to establish the imaging performance at 300 keV following irradiation. The residual contrast, measured on shadow images of a 300 mesh grid, was >80% after corrections for increased dark current, following irradiation with up to 5x10{sup 7} electrons/pixel (equivalent to 80,000 electron/{mu}m{sup 2}). A CMOS sensor with this degree of radiation tolerance would survive a year of normal usage for low-dose electron cryomicroscopy, which is a very useful advance.

  20. Determination of the p-spray profile for n+ p silicon sensors using a MOSFET

    Science.gov (United States)

    Fretwurst, E.; Garutti, E.; Klanner, R.; Kopsalis, I.; Schwandt, J.; Weberpals, M.

    2017-09-01

    The standard technique to electrically isolate the n+ implants of segmented silicon sensors fabricated on high-ohmic p-type silicon are p+-implants. Although the knowledge of the p+-implant dose and of the doping profile is highly relevant for the understanding and optimisation of sensors, this information is usually not available from the vendors, and methods to obtain it are highly welcome. The paper presents methods to obtain this information from circular MOSFETs fabricated as test structures on the same wafer as the sensors. Two circular MOSFETs, one with and one without a p+-implant under the gate, are used for this study. They were produced on Magnetic Czochralski silicon doped with ≈ 3 . 5 × 1012cm-2 of boron and crystal orientation. The drain-source current as function of gate voltage for different back-side voltages is measured at a drain-source voltage of 50 mV in the linear MOSFET region, and the values of threshold voltage and mobility extracted using the standard MOSFET formulae. To determine the bulk doping, the implantation dose and profile from the data, two methods are used, which give compatible results. The doping profile, which varies between 3 . 5 × 1012cm-3 and 2 × 1015cm-3 for the MOSFET with p+-implant, is determined down to a distance of a fraction of a μm from the Si-SiO2 interface. The method of extracting the doping profiles is verified using data from a TCAD simulation of the two MOSFETs. The details of the methods and of the problems encountered are discussed.

  1. Classification of Mixtures of Odorants from Livestock Buildings by a Sensor Array (an Electronic Tongue)

    OpenAIRE

    Abu-Khalaf, Nawaf; Iversen, Jens J?rgen L?nsmann

    2007-01-01

    An electronic tongue comprising different numbers of electrodes was able to classify test mixtures of key odorants characteristic of bioscrubbers of livestock buildings (n-butyrate, iso-valerate, phenolate, p-cresolate, skatole and ammonium). The classification of model solutions indicates that the electronic tongue has a promising potential as an on- line sensor for characterization of odorants in livestock buildings. Back propagation artificial neural network was used for classification. Th...

  2. Applications of Silicon Carbide for High Temperature Electronics and Sensors

    Science.gov (United States)

    Shields, Virgil B.

    1995-01-01

    Silicon carbide (SiC) is a wide bandgap material that shows great promise in high-power and high temperature electronics applications because of its high thermal conductivity and high breakdown electrical field. The excellent physical and electronic properties of SiC allows the fabrication of devices that can operate at higher temperatures and power levels than devices produced from either silicon or GaAs. Although modern electronics depends primarily upon silicon based devices, this material is not capable of handling may special requirements. Devices which operate at high speeds, at high power levels and are to be used in extreme environments at high temperatures and high radiation levels need other materials with wider bandgaps than that of silicon. Many space and terrestrial applications also have a requirement for wide bandgap materials. SiC also has great potential for high power and frequency operation due to a high saturated drift velocity. The wide bandgap allows for unique optoelectronic applications, that include blue light emitting diodes and ultraviolet photodetectors. New areas involving gas sensing and telecommunications offer significant promise. Overall, the properties of SiC make it one of the best prospects for extending the capabilities and operational regimes of the current semiconductor device technology.

  3. Molecular modeling of polymer composite interactions with analytes in electronic nose sensors for environmental monitoring in International Space Station

    Science.gov (United States)

    Shevade, A. V.; Ryan, M. A.; Homer, M. L.; Manfreda, A. M.; Zhou, H.; Manatt, K.

    2002-01-01

    We report a molecular modeling study to investigate the polymer-carbon black (CB) composite-analyte interactions in resistive sensors. These sensors comprise the JPL Electronic Nose (ENose) sensing array developed for monitoring breathing air in human habitats. The polymer in the composite is modeled based on its stereisomerism and sequence isomerism, while the CB is modeled as uncharged naphthalene rings (with no hydrogens). The Dreiding 2.21 force field is used for the polymer and solvent molecules and graphite parameters are assigned to the carbon black atoms. A combination of molecular mechanics (MM) and molecular dynamics (NPT-MD and NVT-MD) techniques are used to obtain the equilibrium composite structure by inserting naphthalene rings in the polymer matrix. Polymers considered for this work include poly(4- vinylphenol), polyethylene oxide, and ethyl cellulose. Analytes studied are representative of both inorganic (ammonia) and organic (methanol, toluene, hydrazine) compounds. The results are analyzed for the composite microstructure by calculating the radial distribution profiles as well as for the sensor response by predicting the interaction energies of the analytes with the composites.

  4. Fiber Bragg grating fabrication for the implementation of sensors in the electronics and optoelectronics laboratory at BUAP

    Science.gov (United States)

    Bracamontes Rodríguez, Y. E.; Beltrán Pérez, G.; Castillo Mixcóatl, J.; Muñoz Aguirre, S.

    2011-09-01

    Fiber Bragg gratings (FBG) are important optical devices since they have been quite successful not only in the field of communications but also in sensor systems and optical fiber lasers. In the sensors area they are generally used as detection elements for different physical parameters such as temperature, strain, flow, etc. In the electronics and optoelectronics laboratory at Benemérita Universidad Autónoma de Puebla (LEyO-BUAP), there are already experimental setups of sensors as well as laser systems, where FBGs are fundamental elements for their adequate performance. However, these FBGs are commercial devices and they present limited characteristics in their transmission profiles, bandwidth and reflectivity. On the other hand, in some occasions, the delivery time from the fabricant to the customer is quite long. Therefore, it is important for LEyO to implement a system to fabricate this kind of devices, which would mean LEyO independence in the technological development. In this work, results of FBGs fabrication based on the phase mask technique are presented. Such mask is optimized for UV and it has a period of 1060 nm. A Nd:YAG pulsed laser with a 5 ns pulse length and an energy of 40 mJ was used as the UV source employing the 4th harmonic generation to obtain a 266 nm wavelength. Ge-doped fiber was used to fabricate the devices.

  5. Electron-transfer mediator for a NAD-glucose dehydrogenase-based glucose sensor.

    Science.gov (United States)

    Kim, Dong-Min; Kim, Min-yeong; Reddy, Sanapalli S; Cho, Jaegeol; Cho, Chul-ho; Jung, Suntae; Shim, Yoon-Bo

    2013-12-03

    A new electron-transfer mediator, 5-[2,5-di (thiophen-2-yl)-1H-pyrrol-1-yl]-1,10-phenanthroline iron(III) chloride (FePhenTPy) oriented to the nicotinamide adenine dinucleotide-dependent-glucose dehydrogenase (NAD-GDH) system was synthesized through a Paal-Knorr condensation reaction. The structure of the mediator was confirmed by Fourier-transform infrared spectroscopy, proton and carbon nucler magnetic resonance spectroscopy, and mass spectroscopy, and its electron-transfer characteristic for a glucose sensor was investigated using voltammetry and impedance spectroscopy. A disposable amperometric glucose sensor with NAD-GDH was constructed with FePhenTPy as an electron-transfer mediator on a screen printed carbon electrode (SPCE) and its performance was evaluated, where the addition of reduces graphene oxide (RGO) to the mediator showed the enhanced sensor performance. The experimental parameters to affect the analytical performance and the stability of the proposed glucose sensor were optimized, and the sensor exhibited a dynamic range between 30 mg/dL and 600 mg/dL with the detection limit of 12.02 ± 0.6 mg/dL. In the real sample experiments, the interference effects by acetaminophen, ascorbic acid, dopamine, uric acid, caffeine, and other monosaccharides (fructose, lactose, mannose, and xylose) were completely avoided through coating the sensor surface with the Nafion film containing lead(IV) acetate. The reliability of proposed glucose sensor was evaluated by the determination of glucose in artificial blood and human whole blood samples.

  6. Demonstration of a Prototype Hydrogen Sensor and Electronics Package - Progress Report 2

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Amanda S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Brosha, Eric [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-06-14

    This is the second progress report on the demonstration of a prototype hydrogen sensor and electronics package. It goes into detail about the five tasks, four of which are already completed as of August 2016, with the final to be completed by January 26, 2017. Then the budget is detailed along with the planned work for May 27, 2016 to July 27, 2016.

  7. Nanocellulose-enabled electronics, energy harvesting devices, smart materials and sensors: a review

    Science.gov (United States)

    Ronald Sabo; Aleksey Yermakov; Chiu Tai Law; Rani Elhajjar

    2016-01-01

    Cellulose nanomaterials have a number of interesting and unique properties that make them well-suited for use in electronics applications such as energy harvesting devices, actuators and sensors. Cellulose nanofibrils and nanocrystals have good mechanical properties, high transparency, and low coefficient of thermal expansion, among other properties that facilitate...

  8. Electronics and Sensor Study with the OKI SOI process

    CERN Document Server

    Arai, Yasuo

    2007-01-01

    While the SOI (Silicon-On-Insulator) device concept is very old, commercialization of the technology is relatively new and growing rapidly in high-speed processor and lowpower applications. Furthermore, features such as latch-up immunity, radiation hardness and high-temperature operation are very attractive in high energy and space applications. Once high-quality bonded SOI wafers became available in the late 90s, it opened up the possibility to get two different kinds of Si on a single wafer. This makes it possible to realize an ideal pixel detector; pairing a fully-depleted radiation sensor with CMOS circuitry in an industrial technology. In 2005 we started Si pixel R&D with OKI Electric Ind. Co., Ltd. which is the first market supplier of Fully-Depleted SOI products. We have developed processes for p+/n+ implants to the substrate and for making connections between the implants and circuits in the OKI 0.15μm FD-SOI CMOS process. We have preformed two Multi Project Wafer (MPW) runs using this SOI proces...

  9. Stretchable Electronic Sensors of Nanocomposite Network Films for Ultrasensitive Chemical Vapor Sensing.

    Science.gov (United States)

    Yan, Hong; Zhong, Mengjuan; Lv, Ze; Wan, Pengbo

    2017-11-01

    A stretchable, transparent, and body-attachable chemical sensor is assembled from the stretchable nanocomposite network film for ultrasensitive chemical vapor sensing. The stretchable nanocomposite network film is fabricated by in situ preparation of polyaniline/MoS2 (PANI/MoS2 ) nanocomposite in MoS2 suspension and simultaneously nanocomposite deposition onto prestrain elastomeric polydimethylsiloxane substrate. The assembled stretchable electronic sensor demonstrates ultrasensitive sensing performance as low as 50 ppb, robust sensing stability, and reliable stretchability for high-performance chemical vapor sensing. The ultrasensitive sensing performance of the stretchable electronic sensors could be ascribed to the synergistic sensing advantages of MoS2 and PANI, higher specific surface area, the reliable sensing channels of interconnected network, and the effectively exposed sensing materials. It is expected to hold great promise for assembling various flexible stretchable chemical vapor sensors with ultrasensitive sensing performance, superior sensing stability, reliable stretchability, and robust portability to be potentially integrated into wearable electronics for real-time monitoring of environment safety and human healthcare. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Rubbery electronics and sensors from intrinsically stretchable elastomeric composites of semiconductors and conductors.

    Science.gov (United States)

    Kim, Hae-Jin; Sim, Kyoseung; Thukral, Anish; Yu, Cunjiang

    2017-09-01

    A general strategy to impart mechanical stretchability to stretchable electronics involves engineering materials into special architectures to accommodate or eliminate the mechanical strain in nonstretchable electronic materials while stretched. We introduce an all solution-processed type of electronics and sensors that are rubbery and intrinsically stretchable as an outcome from all the elastomeric materials in percolated composite formats with P3HT-NFs [poly(3-hexylthiophene-2,5-diyl) nanofibrils] and AuNP-AgNW (Au nanoparticles with conformally coated silver nanowires) in PDMS (polydimethylsiloxane). The fabricated thin-film transistors retain their electrical performances by more than 55% upon 50% stretching and exhibit one of the highest P3HT-based field-effect mobilities of 1.4 cm2/V∙s, owing to crystallinity improvement. Rubbery sensors, which include strain, pressure, and temperature sensors, show reliable sensing capabilities and are exploited as smart skins that enable gesture translation for sign language alphabet and haptic sensing for robotics to illustrate one of the applications of the sensors.

  11. Development of Micro Air Reconnaissance Vehicle as a Test Bed for Advanced Sensors and Electronics

    Science.gov (United States)

    Shams, Qamar A.; Vranas, Thomas L.; Fox, Robert L.; Kuhn, Theodore R.; Ingham, John; Logan, Michael J.; Barnes, Kevin N.; Guenther, Benjamin F.

    2002-01-01

    This paper describes the development of a Micro/Mini Air Reconnaissance Vehicle for advanced sensors and electronics at NASA Langley Research Center over the last year. This vehicle is expected to have a total weight of less than four pounds, a design velocity of 40 mph, an endurance of 15-20 minutes, and a maximum range of 5km. The vehicle has wings that are simple to detach yet retain the correct alignment. The upper fuselage surface has a quick release hatch used to access the interior and also to mount the varying propulsion systems. The sensor suite developed for this vehicle consists of a Pitot-static measurement system for determining air speed, an absolute pressure measurement for determining altitude, magnetic direction measurement, and three orthogonal gyros to determine body angular rates. Swarming GPS-guidance and in-flight maneuvering is discussed, as well as design and installation of some other advance sensors like MEMS microphones, infrared cameras, GPS, humidity sensors, and an ultrasonic sonar sensor. Also low cost, small size, high performance control and navigation system for the Micro Air Vehicle is discussed. At the end, laboratory characterization of different sensors, motors, propellers, and batteries will be discussed.

  12. Kelvin probe microscopy and electronic transport measurements in reduced graphene oxide chemical sensors

    Science.gov (United States)

    Kehayias, Christopher E.; MacNaughton, Samuel; Sonkusale, Sameer; Staii, Cristian

    2013-06-01

    Reduced graphene oxide (RGO) is an electronically hybrid material that displays remarkable chemical sensing properties. Here, we present a quantitative analysis of the chemical gating effects in RGO-based chemical sensors. The gas sensing devices are patterned in a field-effect transistor geometry, by dielectrophoretic assembly of RGO platelets between gold electrodes deposited on SiO2/Si substrates. We show that these sensors display highly selective and reversible responses to the measured analytes, as well as fast response and recovery times (tens of seconds). We use combined electronic transport/Kelvin probe microscopy measurements to quantify the amount of charge transferred to RGO due to chemical doping when the device is exposed to electron-acceptor (acetone) and electron-donor (ammonia) analytes. We demonstrate that this method allows us to obtain high-resolution maps of the surface potential and local charge distribution both before and after chemical doping, to identify local gate-susceptible areas on the RGO surface, and to directly extract the contact resistance between the RGO and the metallic electrodes. The method presented is general, suggesting that these results have important implications for building graphene and other nanomaterial-based chemical sensors.

  13. Electron number density profiles derived from radio occultation on the CASSIOPE spacecraft

    Science.gov (United States)

    Shume, Esayas B.; Vergados, Panagiotis; Komjathy, Attila; Langley, Richard B.; Durgonics, Tibor

    2017-09-01

    This paper presents electron number density profiles derived from high-resolution Global Positioning System (GPS) radio occultation (RO) observations performed using the Enhanced Polar Outflow Probe payload on the high inclination CAScade, Smallsat and IOnospheric Polar Explorer (CASSIOPE) spacecraft. We have developed and applied a novel inverse Abel transform algorithm on high rate RO total electron content measurements performed along GPS to CASSIOPE radio links to recover electron density profiles. The high-resolution density profiles inferred from the CASSIOPE RO are (1) in very good agreement with density profiles estimated from ionosonde data, measured over stations nearby to the latitude and longitude of the RO tangent points; (2) in good agreement with density profiles inferred from GPS RO measured by the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC); and (3) in general agreement with density profiles estimated using the International Reference Ionosphere climatological model. Using both CASSIOPE and COSMIC RO observations, we identify, for the first time, that there exist differences in the characteristics of the electron number density profiles retrieved over landmasses and oceans. The density profiles over oceans exhibit widespread values and scale heights compared to density profiles over landmasses. We provide an explanation for the ocean-landmass discrepancy in terms of the unique wave coupling mechanisms operating over oceans and landmasses.

  14. Electronic Measurement Systems and Procedures for Optical Encoder and Force Sensor Studying

    Directory of Open Access Journals (Sweden)

    Dorina Purcaru

    2009-10-01

    Full Text Available The experimental measurement systems arevery useful in engineering education because the studentscan use and verify their previous knowledge aboutsensors and transducers, signal conditioning and dataprocessing. This paper presents two electronicmeasurement systems which enable the computerizedstudy of the optical encoder and force sensor, respectively.The first sensor studying procedure performs theunderstanding and checking of the rotary incrementalencoder working modes and methods for resolutionimprovement, displacement and velocity measurement,and motion sense discrimination. The second sensorstudying procedure supposes the assignation of themeasurement points, plotting the transfer characteristicand computing some parameters (zero error, differentialsensitivity, relative sensitivity of the strain gaugetransducer; the measured mass of the tested object canalso be displayed. Each electronic measurement systemcontains signal conditioning circuits, data acquisitionboard (organized around a microcontroller and an IBMPCcompatible computer; the data acquisition board isserial connected to computer. A friendly user interfaceenables each computerized sensor study. The paper alsoincludes many experimental results.

  15. Infrared Spectroscope for Electron Bunch-length Measurement: Heat Sensor Parameters Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Domgmo-Momo, Gilles; /Towson U. /SLAC

    2012-09-05

    The Linac Coherent Light Source (LCLS) is used for many experiments. Taking advantage of the free electron laser (FEL) process, scientists of various fields perform experiments of all kind. Some for example study protein folding; other experiments are more interested in the way electrons interact with the molecules before they are destroyed. These experiments among many others have very little information about the electrons x-ray produced by the FEL, except that the FEL is using bunches less than 10 femtoseconds long. To be able to interpret the data collected from those experiments, more accurate information is needed about the electron's bunch-length. Existing bunch length measurement techniques are not suitable for the measurement of such small time scales. Hence the need to design a device that will provide more precise information about the electron bunch length. This paper investigates the use of a pyreoelectric heat sensor that has a sensitivity of about 1.34 micro amps per watt for the single cell detector. Such sensitivity, added to the fact that the detector is an array sensor, makes the detector studied the primary candidate to be integrated to an infrared spectrometer designed to better measure the LCLS electron bunch length.

  16. CASSINI RSS: IONOSPHERIC ELECTRON DENSITY PROFILES EDP1 V1.0

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains the complete collection of the published Cassini radio occultation electron density profiles of the Titan ionosphere as of September 2008.

  17. Electronic structure of hafnium: A Compton profile study

    Indian Academy of Sciences (India)

    The calculations were done for the hexagonal (P63/mmc) structure of Hf with lattice parameters a = 3.195 Å and c = 5.051 Å. ECP's have been taken from [25] and the valence basis sets for 5d and 6s electrons have been used after reoptimiza- tion. It may be mentioned that due to the non-availability of all electron basis sets.

  18. Taste profile characterization of white ginseng by electronic tongue ...

    African Journals Online (AJOL)

    We conducted taste profile analysis of white ginseng (Panax ginseng) using a taste-sensing system. Taste such as sourness, bitterness, astringent, aftertaste, umami, richness, and saltiness of the four subfractions (n-hexane fr. = Pg1; EtOAc fr. = Pg2; CHCl3 fr. = Pg3; n-BuOH fr. = Pg4) from white ginseng was checked using ...

  19. Pemanfaatan Electronic Nose sebagai Sensor Kimiawi Urin Guna Melacak Birahi Sapi (ELECTRONIC NOSE AS URINARY CHEMICAL SENSOR FOR DETERMINING ESTROUS PHASE IN CATTLE

    Directory of Open Access Journals (Sweden)

    Pudji Astuti

    2017-01-01

    Full Text Available The timing of artificial insemination relies largely on behavioral observation of estrus. The problemfaced is that not all cattle shows signs of estrus significantly, which affect the accuracy of insemination,and therefore,the success rate of Artificial Insemination is less than 50%. Recently, the determination ofestradiol levels as an indicator of estrus is done by observation of physical signs and doing ELISA test,which is expensive and provide longer time. In order to solve these problems, a tool estrus detector is madenamely Electronic Nose (EN. Determination of estrus with EN is cheaper because it does not need to usecomplexmaterials, just only use the samples. Mechanism of action of EN is using a sensor that is vaporized,while animals estrus will emit pheromones that are vaporized. Theaim of this study was to determinewhether the stage of estrus can be detected by using EN. Urine of female Ongole Crossbred which maintainedin Kuwang, district of Cangkringan, Yogyakarta, with BCS of 3 was used in this research. The sample wascollected shortly before injection of dinoprost as estrus synchronization then it repeated when cattle got estrus phase. The urinary sample of the estrus cattle was sensitive to methane, propane, butane, whereasin non-estrus cattle, besides the three of these component (methane, propane, butane, sensor was alsocaptured hydrogen sulfide. Furthermore, our electronic nose had been able to distinguish estrus phase andnon-estrus based on domain area.Thus, the Electronic Nose is very prospect used as a detector of estrus incattle. Hydrogen disulfide could possibly be used as an indicator comparison between cow estrus and nonestrus.

  20. Hierarchical graphene-polyaniline nanocomposite films for high-performance flexible electronic gas sensors

    Science.gov (United States)

    Guo, Yunlong; Wang, Ting; Chen, Fanhong; Sun, Xiaoming; Li, Xiaofeng; Yu, Zhongzhen; Wan, Pengbo; Chen, Xiaodong

    2016-06-01

    A hierarchically nanostructured graphene-polyaniline composite film is developed and assembled for a flexible, transparent electronic gas sensor to be integrated into wearable and foldable electronic devices. The hierarchical nanocomposite film is obtained via aniline polymerization in reduced graphene oxide (rGO) solution and simultaneous deposition on flexible PET substrate. The PANI nanoparticles (PPANI) anchored onto rGO surfaces (PPANI/rGO) and the PANI nanofiber (FPANI) are successfully interconnected and deposited onto flexible PET substrates to form hierarchical nanocomposite (PPANI/rGO-FPANI) network films. The assembled flexible, transparent electronic gas sensor exhibits high sensing performance towards NH3 gas concentrations ranging from 100 ppb to 100 ppm, reliable transparency (90.3% at 550 nm) for the PPANI/rGO-FPANI film (6 h sample), fast response/recovery time (36 s/18 s), and robust flexibility without an obvious performance decrease after 1000 bending/extending cycles. The excellent sensing performance could probably be ascribed to the synergetic effects and the relatively high surface area (47.896 m2 g-1) of the PPANI/rGO-FPANI network films, the efficient artificial neural network sensing channels, and the effectively exposed active surfaces. It is expected to hold great promise for developing flexible, cost-effective, and highly sensitive electronic sensors with real-time analysis to be potentially integrated into wearable flexible electronics.A hierarchically nanostructured graphene-polyaniline composite film is developed and assembled for a flexible, transparent electronic gas sensor to be integrated into wearable and foldable electronic devices. The hierarchical nanocomposite film is obtained via aniline polymerization in reduced graphene oxide (rGO) solution and simultaneous deposition on flexible PET substrate. The PANI nanoparticles (PPANI) anchored onto rGO surfaces (PPANI/rGO) and the PANI nanofiber (FPANI) are successfully

  1. Metal Oxide Sensors for Electronic Noses and Their Application to Food Analysis

    Science.gov (United States)

    Berna, Amalia

    2010-01-01

    Electronic noses (E-noses) use various types of electronic gas sensors that have partial specificity. This review focuses on commercial and experimental E-noses that use metal oxide semi-conductors. The review covers quality control applications to food and beverages, including determination of freshness and identification of contaminants or adulteration. Applications of E-noses to a wide range of foods and beverages are considered, including: meat, fish, grains, alcoholic drinks, non-alcoholic drinks, fruits, milk and dairy products, olive oils, nuts, fresh vegetables and eggs. PMID:22319332

  2. Decontamination of digital image sensors and assessment of electron microscope performance in a BSL-3 containment

    OpenAIRE

    Michael B. Sherman; Juan Trujillo; Bammes, Benjamin E.; Liang Jin; Matthias W. Stumpf; Weaver, Scott C.

    2015-01-01

    A unique biological safety level (BSL)-3 cryo-electron microscopy facility with a 200 keV high-end cryo-electron microscope has been commissioned at the University of Texas Medical Branch (UTMB) to study the structure of viruses and bacteria classified as select agents. We developed a microscope decontamination protocol based on chlorine dioxide gas with a continuous flow system. In this paper we report on testing digital camera sensors (both CCD and CMOS direct detector) in a BSL-3 environme...

  3. Decontamination of digital image sensors and assessment of electron microscope performance in a BSL-3 containment

    Directory of Open Access Journals (Sweden)

    Michael B. Sherman

    2015-05-01

    Full Text Available A unique biological safety level (BSL-3 cryo-electron microscopy facility with a 200 keV high-end cryo-electron microscope has been commissioned at the University of Texas Medical Branch (UTMB to study the structure of viruses and bacteria classified as select agents. We developed a microscope decontamination protocol based on chlorine dioxide gas with a continuous flow system. In this paper we report on testing digital camera sensors (both CCD and CMOS direct detector in a BSL-3 environment, and microscope performance after chlorine dioxide (ClO2 decontamination cycles.

  4. Metal Oxide Sensors for Electronic Noses and Their Application to Food Analysis

    Directory of Open Access Journals (Sweden)

    Amalia Berna

    2010-04-01

    Full Text Available Electronic noses (E-noses use various types of electronic gas sensors that have partial specificity. This review focuses on commercial and experimental E-noses that use metal oxide semi-conductors. The review covers quality control applications to food and beverages, including determination of freshness and identification of contaminants or adulteration. Applications of E-noses to a wide range of foods and beverages are considered, including: meat, fish, grains, alcoholic drinks, non-alcoholic drinks, fruits, milk and dairy products, olive oils, nuts, fresh vegetables and eggs.

  5. A simple, low-cost conductive composite material for 3D printing of electronic sensors.

    Science.gov (United States)

    Leigh, Simon J; Bradley, Robert J; Purssell, Christopher P; Billson, Duncan R; Hutchins, David A

    2012-01-01

    3D printing technology can produce complex objects directly from computer aided digital designs. The technology has traditionally been used by large companies to produce fit and form concept prototypes ('rapid prototyping') before production. In recent years however there has been a move to adopt the technology as full-scale manufacturing solution. The advent of low-cost, desktop 3D printers such as the RepRap and Fab@Home has meant a wider user base are now able to have access to desktop manufacturing platforms enabling them to produce highly customised products for personal use and sale. This uptake in usage has been coupled with a demand for printing technology and materials able to print functional elements such as electronic sensors. Here we present formulation of a simple conductive thermoplastic composite we term 'carbomorph' and demonstrate how it can be used in an unmodified low-cost 3D printer to print electronic sensors able to sense mechanical flexing and capacitance changes. We show how this capability can be used to produce custom sensing devices and user interface devices along with printed objects with embedded sensing capability. This advance in low-cost 3D printing with offer a new paradigm in the 3D printing field with printed sensors and electronics embedded inside 3D printed objects in a single build process without requiring complex or expensive materials incorporating additives such as carbon nanotubes.

  6. A simple, low-cost conductive composite material for 3D printing of electronic sensors.

    Directory of Open Access Journals (Sweden)

    Simon J Leigh

    Full Text Available 3D printing technology can produce complex objects directly from computer aided digital designs. The technology has traditionally been used by large companies to produce fit and form concept prototypes ('rapid prototyping' before production. In recent years however there has been a move to adopt the technology as full-scale manufacturing solution. The advent of low-cost, desktop 3D printers such as the RepRap and Fab@Home has meant a wider user base are now able to have access to desktop manufacturing platforms enabling them to produce highly customised products for personal use and sale. This uptake in usage has been coupled with a demand for printing technology and materials able to print functional elements such as electronic sensors. Here we present formulation of a simple conductive thermoplastic composite we term 'carbomorph' and demonstrate how it can be used in an unmodified low-cost 3D printer to print electronic sensors able to sense mechanical flexing and capacitance changes. We show how this capability can be used to produce custom sensing devices and user interface devices along with printed objects with embedded sensing capability. This advance in low-cost 3D printing with offer a new paradigm in the 3D printing field with printed sensors and electronics embedded inside 3D printed objects in a single build process without requiring complex or expensive materials incorporating additives such as carbon nanotubes.

  7. Electronic properties and Compton profiles of silver iodide

    Indian Academy of Sciences (India)

    calculations is listed in table 1. In the present calculations, all-electron basis sets of Gaussian-type orbitals. (GTOs) for Ag and I have been taken from ref. [34]. These basis sets were opti- mized using BILLY software. For a faster convergence of self-consistent-field (SCF) cycles, the BROYDEN scheme [35] was applied for all ...

  8. Determination of the vertical electron-density profile in ionospheric tomography: experimental results

    Directory of Open Access Journals (Sweden)

    C. N. Mitchell

    Full Text Available The reconstruction of the vertical electron-density profile is a fundamental problem in ionospheric tomography. Lack of near-horizontal ray paths limits the information available on the vertical profile, so that the resultant image of electron density is biased in a horizontal sense. The vertical profile is of great importance as it affects the authenticity of the entire tomographic image. A new method is described whereby the vertical profile is selected using relative total-electron-content measurements. The new reconstruction process has been developed from modelling studies. A range of background ionospheres, representing many possible peak heights, scale heights and electron densities are formed from a Chapman profile on the bottomside with a range of topside profiles. The iterative reconstruction process is performed on all of these background ionospheres and a numerical selection criterion employed to select the final image. The resulting tomographic images show excellent agreement in electron density when compared with independent verification provided by the EISCAT radar.

  9. A multi-channel opto-electronic sensor to accurately monitor heart rate against motion artefact during exercise

    National Research Council Canada - National Science Library

    Alzahrani, Abdullah; Hu, Sijung; Azorin-Peris, Vicente; Barrett, Laura; Esliger, Dale; Hayes, Matthew; Akbare, Shafique; Achart, Jérôme; Kuoch, Sylvain

    2015-01-01

    This study presents the use of a multi-channel opto-electronic sensor (OEPS) to effectively monitor critical physiological parameters whilst preventing motion artefact as increasingly demanded by personal healthcare...

  10. Sensors

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, H. [PBI-Dansensor A/S (Denmark); Toft Soerensen, O. [Risoe National Lab., Materials Research Dept. (Denmark)

    1999-10-01

    A new type of ceramic oxygen sensors based on semiconducting oxides was developed in this project. The advantage of these sensors compared to standard ZrO{sub 2} sensors is that they do not require a reference gas and that they can be produced in small sizes. The sensor design and the techniques developed for production of these sensors are judged suitable by the participating industry for a niche production of a new generation of oxygen sensors. Materials research on new oxygen ion conducting conductors both for applications in oxygen sensors and in fuel was also performed in this project and finally a new process was developed for fabrication of ceramic tubes by dip-coating. (EHS)

  11. Hildebrand and Hansen solubility parameters from molecular dynamics with applications to electronic nose polymer sensors.

    Science.gov (United States)

    Belmares, M; Blanco, M; Goddard, W A; Ross, R B; Caldwell, G; Chou, S-H; Pham, J; Olofson, P M; Thomas, Cristina

    2004-11-30

    We introduce the Cohesive Energy Density (CED) method, a multiple sampling Molecular Dynamics computer simulation procedure that may offer higher consistency in the estimation of Hildebrand and Hansen solubility parameters. The use of a multiple sampling technique, combined with a simple but consistent molecular force field and quantum mechanically determined atomic charges, allows for the precise determination of solubility parameters in a systematic way (sigma = 0.4 hildebrands). The CED method yields first-principles Hildebrand parameter predictions in good agreement with experiment [root-mean-square (rms) = 1.1 hildebrands]. We apply the CED method to model the Caltech electronic nose, an array of 20 polymer sensors. Sensors are built with conducting leads connected through thin-film polymers loaded with carbon black. Odorant detection relies on a change in electric resistivity of the polymer film as function of the amount of swelling caused by the odorant compound. The amount of swelling depends upon the chemical composition of the polymer and the odorant molecule. The pattern is unique, and unambiguously identifies the compound. Experimentally determined changes in relative resistivity of seven polymer sensors upon exposure to 24 solvent vapors were modeled with the CED estimated Hansen solubility components. Predictions of polymer sensor responses result in Pearson R2 coefficients between 0.82 and 0.99. Copyright 2004 Wiley Periodicals, Inc.

  12. Photometer for monitoring the thickness of inkjet printed films for organic electronic and sensor applications

    Science.gov (United States)

    Im, Jisun; Sengupta, Sandip K.; Whitten, James E.

    2010-03-01

    Inkjet printed organic thin films are being used for a variety of electronic and sensor applications with advantages that include ease of fabrication and reproducibility. Construction and use of a low-cost photometer based on a light-emitting diode (LED) light source and a photodiode detector are described. The photometer attaches to the exit of the printer with the transparent substrate onto which the film is printed passing between the LED and photodiode. By measuring the output voltage of the detector, the transmittance and absorbance of the inkjet printed film can be calculated in real-time. Since absorbance is linearly proportional to thickness in the Beer-Lambert regime, the thickness of the film may be monitored and controlled by varying the number of passes through the printer. Use of the photometer is demonstrated for inkjet printed films of monolayer-protected colloidal gold nanoparticles that function as chemical vapor sensors. The photometer may find applications in both research and quality control related to the manufacture of organic electronic devices and sensors and enables "feedback-controlled" inkjet printing.

  13. Scalable Microfabrication Procedures for Adhesive-Integrated Flexible and Stretchable Electronic Sensors

    Science.gov (United States)

    Kang, Dae Y.; Kim, Yun-Soung; Ornelas, Gladys; Sinha, Mridu; Naidu, Keerthiga; Coleman, Todd P.

    2015-01-01

    New classes of ultrathin flexible and stretchable devices have changed the way modern electronics are designed to interact with their target systems. Though more and more novel technologies surface and steer the way we think about future electronics, there exists an unmet need in regards to optimizing the fabrication procedures for these devices so that large-scale industrial translation is realistic. This article presents an unconventional approach for facile microfabrication and processing of adhesive-peeled (AP) flexible sensors. By assembling AP sensors on a weakly-adhering substrate in an inverted fashion, we demonstrate a procedure with 50% reduced end-to-end processing time that achieves greater levels of fabrication yield. The methodology is used to demonstrate the fabrication of electrical and mechanical flexible and stretchable AP sensors that are peeled-off their carrier substrates by consumer adhesives. In using this approach, we outline the manner by which adhesion is maintained and buckling is reduced for gold film processing on polydimethylsiloxane substrates. In addition, we demonstrate the compatibility of our methodology with large-scale post-processing using a roll-to-roll approach. PMID:26389915

  14. Photometer for monitoring the thickness of inkjet printed films for organic electronic and sensor applications.

    Science.gov (United States)

    Im, Jisun; Sengupta, Sandip K; Whitten, James E

    2010-03-01

    Inkjet printed organic thin films are being used for a variety of electronic and sensor applications with advantages that include ease of fabrication and reproducibility. Construction and use of a low-cost photometer based on a light-emitting diode (LED) light source and a photodiode detector are described. The photometer attaches to the exit of the printer with the transparent substrate onto which the film is printed passing between the LED and photodiode. By measuring the output voltage of the detector, the transmittance and absorbance of the inkjet printed film can be calculated in real-time. Since absorbance is linearly proportional to thickness in the Beer-Lambert regime, the thickness of the film may be monitored and controlled by varying the number of passes through the printer. Use of the photometer is demonstrated for inkjet printed films of monolayer-protected colloidal gold nanoparticles that function as chemical vapor sensors. The photometer may find applications in both research and quality control related to the manufacture of organic electronic devices and sensors and enables "feedback-controlled" inkjet printing.

  15. Scalable Microfabrication Procedures for Adhesive-Integrated Flexible and Stretchable Electronic Sensors

    Directory of Open Access Journals (Sweden)

    Dae Y. Kang

    2015-09-01

    Full Text Available New classes of ultrathin flexible and stretchable devices have changed the way modern electronics are designed to interact with their target systems. Though more and more novel technologies surface and steer the way we think about future electronics, there exists an unmet need in regards to optimizing the fabrication procedures for these devices so that large-scale industrial translation is realistic. This article presents an unconventional approach for facile microfabrication and processing of adhesive-peeled (AP flexible sensors. By assembling AP sensors on a weakly-adhering substrate in an inverted fashion, we demonstrate a procedure with 50% reduced end-to-end processing time that achieves greater levels of fabrication yield. The methodology is used to demonstrate the fabrication of electrical and mechanical flexible and stretchable AP sensors that are peeled-off their carrier substrates by consumer adhesives. In using this approach, we outline the manner by which adhesion is maintained and buckling is reduced for gold film processing on polydimethylsiloxane substrates. In addition, we demonstrate the compatibility of our methodology with large-scale post-processing using a roll-to-roll approach.

  16. Scalable Microfabrication Procedures for Adhesive-Integrated Flexible and Stretchable Electronic Sensors.

    Science.gov (United States)

    Kang, Dae Y; Kim, Yun-Soung; Ornelas, Gladys; Sinha, Mridu; Naidu, Keerthiga; Coleman, Todd P

    2015-09-16

    New classes of ultrathin flexible and stretchable devices have changed the way modern electronics are designed to interact with their target systems. Though more and more novel technologies surface and steer the way we think about future electronics, there exists an unmet need in regards to optimizing the fabrication procedures for these devices so that large-scale industrial translation is realistic. This article presents an unconventional approach for facile microfabrication and processing of adhesive-peeled (AP) flexible sensors. By assembling AP sensors on a weakly-adhering substrate in an inverted fashion, we demonstrate a procedure with 50% reduced end-to-end processing time that achieves greater levels of fabrication yield. The methodology is used to demonstrate the fabrication of electrical and mechanical flexible and stretchable AP sensors that are peeled-off their carrier substrates by consumer adhesives. In using this approach, we outline the manner by which adhesion is maintained and buckling is reduced for gold film processing on polydimethylsiloxane substrates. In addition, we demonstrate the compatibility of our methodology with large-scale post-processing using a roll-to-roll approach.

  17. Impact of low-dose electron irradiation on n+p silicon strip sensors

    CERN Document Server

    Adam, W.; Dragicevic, M.; Friedl, M.; Fruehwirth, R.; Hoch, M.; Hrubec, J.; Krammer, M.; Treberspurg, W.; Waltenberger, W.; Alderweireldt, S.; Beaumont, W.; Janssen, X.; Luyckx, S.; Van Mechelen, P.; Van Remortel, N.; Van Spilbeeck, A.; Barria, P.; Caillol, C.; Clerbaux, B.; De Lentdecker, G.; Dobur, D.; Favart, L.; Grebenyuk, A.; Lenzi, Th.; Leonard, A.; Maerschalk, Th.; Mohammadi, A.; Pernie, L.; Randle-Conde, A.; Reis, T.; Seva, T.; Thomas, L.; Vander Velde, C.; Vanlaer, P.; Wang, J.; Zenoni, F.; Abu Zeid, S.; Blekman, F.; De Bruyn, I.; D'Hondt, J.; Daci, N.; Deroover, K.; Heracleous, N.; Keaveney, J.; Lowette, S.; Moreels, L.; Olbrechts, A.; Python, Q.; Tavernier, S.; Van Mulders, P.; Van Onsem, G.; Van Parijs, I.; Strom, D.A.; Basegmez, S.; Bruno, G.; Castello, R.; Caudron, A.; Ceard, L.; De Callatay, B.; Delaere, C.; Pree, T.Du; Forthomme, L.; Giammanco, A.; Hollar, J.; Jez, P.; Michotte, D.; Nuttens, C.; Perrini, L.; Pagano, D.; Quertenmont, L.; Selvaggi, M.; Marono, M.Vidal; Beliy, N.; Caebergs, T.; Daubie, E.; Hammad, G.H.; Harkonen, J.; Lampen, T.; Luukka, P.R.; Maenpaa, T.; Peltola, T.; Tuominen, E.; Tuovinen, E.; Eerola, P.; Tuuva, T.; Beaulieu, G.; Boudoul, G.; Combaret, C.; Contardo, D.; Gallbit, G.; Lumb, N.; Mathez, H.; Mirabito, L.; Perries, S.; Sabes, D.; Vander Donckt, M.; Verdier, P.; Viret, S.; Zoccarato, Y.; Agram, J.L.; Conte, E.; Fontaine, J.Ch.; Andrea, J.; Bloch, D.; Bonnin, C.; Brom, J.M.; Chabert, E.; Charles, L.; Goetzmann, Ch.; Gross, L.; Hosselet, J.; Mathieu, C.; Richer, M.; Skovpen, K.; Autermann, C.; Edelhoff, M.; Esser, H.; Feld, L.; Karpinski, W.; Klein, K.; Lipinski, M.; Ostapchuk, A.; Pierschel, G.; Preuten, M.; Raupach, F.; Sammet, J.; Schael, S.; Schwering, G.; Wittmer, B.; Wlochal, M.; Zhukov, V.; Pistone, C.; Fluegge, G.; Kuensken, A.; Geisler, M.; Pooth, O.; Stahl, A.; Bartosik, N.; Behr, J.; Burgmeier, A.; Calligaris, L.; Dolinska, G.; Eckerlin, G.; Eckstein, D.; Eichhorn, T.; Fluke, G.; Garcia, J.Garay; Gizhko, A.; Hansen, K.; Harb, A.; Hauk, J.; Kalogeropoulos, A.; Kleinwort, C.; Korol, I.; Lange, W.; Lohmann, W.; Mankel, R.; Maser, H.; Mittag, G.; Muhl, C.; Mussgiller, A.; Nayak, A.; Ntomari, E.; Perrey, H.; Pitzl, D.; Schroeder, M.; Seitz, C.; Spannagel, S.; Zuber, A.; Biskop, H.; Blobel, V.; Buhmann, P.; Centis-Vignali, M.; Draeger, A.R.; Erfle, J.; Garutti, E.; Haller, J.; Henkel, Ch.; Hoffmann, M.; Junkes, A.; Klanner, R.; Lapsien, T.; Mattig, S.; Matysek, M.; Perieanu, A.; Poehlsen, J.; Poehlsen, T.; Scharf, Ch.; Schleper, P.; Schmidt, A.; Schuwalow, S.; Schwandt, J.; Sola, V.; Steinbruck, G.; Vormwald, B.; Wellhausen, J.; Barvich, T.; Barth, Ch.; Boegelspacher, F.; De Boer, W.; Butz, E.; Casele, M.; Colombo, F.; Dierlamm, A.; Eber, R.; Freund, B.; Hartmann, F.; Hauth, Th.; Heindl, S.; Hoffmann, K.H.; Husemann, U.; Kornmeyer, A.; Mallows, S.; Muller, Th.; Nuernberg, A.; Printz, M.; Simonis, H.J.; Steck, P.; Weber, M.; Weiler, Th.; Bhardwaj, A.; Kumar, A.; Ranjan, K.; Bakhshiansohl, H.; Behnamian, H.; Khakzad, M.; Naseri, M.; Cariola, P.; De Robertis, G.; Fiore, L.; Franco, M.; Loddo, F.; Sala, G.; Silvestris, L.; Creanza, D.; De Palma, M.; Maggi, G.; My, S.; Selvaggi, G.; Albergo, S.; Cappello, G.; Chiorboli, M.; Costa, S.; Giordano, F.; Di Mattia, A.; Potenza, R.; Saizu, M.A.; Tricomi, A.; Tuve, C.; Barbagli, G.; Brianzi, M.; Ciaranfi, R.; Civinini, C.; Gallo, E.; Meschini, M.; Paoletti, S.; Sguazzoni, G.; Ciulli, V.; D'Alessandro, R.; Gonzi, S.; Gori, V.; Focardi, E.; Lenzi, P.; Scarlini, E.; Tropiano, A.; Viliani, L.; Ferro, F.; Robutti, E.; Lo Vetere, M.; Gennai, S.; Malvezzi, S.; Menasce, D.; Moroni, L.; Pedrini, D.; Dinardo, M.; Fiorendi, S.; Manzoni, R.A.; Azzi, P.; Bacchetta, N.; Bisello, D.; Dall'Osso, M.; Dorigo, T.; Giubilato, P.; Pozzobon, N.; Tosi, M.; Zucchetta, A.; De Canio, F.; Gaioni, L.; Manghisoni, M.; Nodari, B.; Re, V.; Traversi, G.; Comotti, D.; Ratti, L.; Bilei, G.M.; Bissi, L.; Checcucci, B.; Magalotti, D.; Menichelli, M.; Saha, A.; Servoli, L.; Storchi, L.; Biasini, M.; Conti, E.; Ciangottini, D.; Fano, L.; Lariccia, P.; Mantovani, G.; Passeri, D.; Placidi, P.; Salvatore, M.; Santocchia, A.; Solestizi, L.A.; Spiezia, A.; Demaria, N.; Rivetti, A.; Bellan, R.; Casasso, S.; Costa, M.; Covarelli, R.; Migliore, E.; Monteil, E.; Musich, M.; Pacher, L.; Ravera, F.; Romero, A.; Solano, A.; Trapani, P.; Jaramillo Echeverria, R.; Fernandez, M.; Gomez, G.; Moya, D.; F. Gonzalez Sanchez, J.; Munoz Sanchez, F.J.; Vila, I.; Virto, A.L.; Abbaneo, D.; Ahmed, I.; Albert, E.; Auzinger, G.; Berruti, G.; Bianchi, G.; Blanchot, G.; Breuker, H.; Ceresa, D.; Christiansen, J.; Cichy, K.; Daguin, J.; D'Alfonso, M.; D'Auria, A.; Detraz, S.; De Visscher, S.; Deyrail, D.; Faccio, F.; Felici, D.; Frank, N.; Gill, K.; Giordano, D.; Harris, P.; Honma, A.; Kaplon, J.; Kornmayer, A.; Kortelainen, M.; Kottelat, L.; Kovacs, M.; Mannelli, M.; Marchioro, A.; Marconi, S.; Martina, S.; Mersi, S.; Michelis, S.; Moll, M.; Onnela, A.; Pakulski, T.; Pavis, S.; Peisert, A.; Pernot, J.F.; Petagna, P.; Petrucciani, G.; Postema, H.; Rose, P.; Rzonca, M.; Stoye, M.; Tropea, P.; Troska, J.; Tsirou, A.; Vasey, F.; Vichoudis, P.; Verlaat, B.; Zwalinski, L.; Bachmair, F.; Becker, R.; Bani, L.; di Calafiori, D.; Casal, B.; Djambazov, L.; Donega, M.; Dunser, M.; Eller, P.; Grab, C.; Hits, D.; Horisberger, U.; Hoss, J.; Kasieczka, G.; Lustermann, W.; Mangano, B.; Marionneau, M.; Martinez Ruiz del Arbol, P.; Masciovecchio, M.; Perrozzi, L.; Roeser, U.; Rossini, M.; Starodumov, A.; Takahashi, M.; Wallny, R.; Amsler, C.; Bosiger, K.; Caminada, L.; Canelli, F.; Chiochia, V.; De Cosa, A.; Galloni, C.; Hreus, T.; Kilminster, B.; Lange, C.; Maier, R.; Ngadiuba, J.; Pinna, D.; Robmann, P.; Taroni, S.; Yang, Y.; Bertl, W.; Deiters, K.; Erdmann, W.; Horisberger, R.; Kaestli, H.C.; Kotlinski, D.; Langenegger, U.; Meier, B.; Rohe, T.; Streuli, S.; Chen, P.H.; Dietz, C.; Grundler, U.; Hou, W.S.; Lu, R.S.; Moya, M.; Wilken, R.; Cussans, D.; Flacher, H.; Goldstein, J.; Grimes, M.; Jacob, J.; El Nasr-Storey, S.Seif; Cole, J.; Hobson, P.; Leggat, D.; Reid, I.D.; Teodorescu, L.; Bainbridge, R.; Dauncey, P.; Fulcher, J.; Hall, G.; Magnan, A.M.; Pesaresi, M.; Raymond, D.M.; Uchida, K.; Coughlan, J.A.; Harder, K.; Ilic, J.; Tomalin, I.R.; Garabedian, A.; Heintz, U.; Narain, M.; Nelson, J.; Sagir, S.; Speer, T.; Swanson, J.; Tersegno, D.; Watson-Daniels, J.; Chertok, M.; Conway, J.; Conway, R.; Flores, C.; Lander, R.; Pellett, D.; Ricci-Tam, F.; Squires, M.; Thomson, J.; Yohay, R.; Burt, K.; Ellison, J.; Hanson, G.; Malberti, M.; Olmedo, M.; Cerati, G.; Sharma, V.; Vartak, A.; Yagil, A.; Della Porta, G.Zevi; Dutta, V.; Gouskos, L.; Incandela, J.; Kyre, S.; McColl, N.; Mullin, S.; White, D.; Cumalat, J.P.; Ford, W.T.; Gaz, A.; Krohn, M.; Stenson, K.; Wagner, S.R.; Baldin, B.; Bolla, G.; Burkett, K.; Butler, J.; Cheung, H.; Chramowicz, J.; Christian, D.; Cooper, W.E.; Deptuch, G.; Derylo, G.; Gingu, C.; Gruenendahl, S.; Hasegawa, S.; Hoff, J.; Howell, J.; Hrycyk, M.; Jindariani, S.; Johnson, M.; Jung, A.; Joshi, U.; Kahlid, F.; Lei, C.M.; Lipton, R.; Liu, T.; Los, S.; Matulik, M.; Merkel, P.; Nahn, S.; Prosser, A.; Rivera, R.; Shenai, A.; Spiegel, L.; Tran, N.; Uplegger, L.; Voirin, E.; Yin, H.; Adams, M.R.; Berry, D.R.; Evdokimov, A.; Evdokimov, O.; Gerber, C.E.; Hofman, D.J.; Kapustka, B.K.; O'Brien, C.; Sandoval Gonzalez, D.I.; Trauger, H.; Turner, P.; Parashar, N.; Stupak, J., III; Bortoletto, D.; Bubna, M.; Hinton, N.; Jones, M.; Miller, D.H.; Shi, X.; Tan, P.; Baringer, P.; Bean, A.; Benelli, G.; Gray, J.; Majumder, D.; Noonan, D.; Sanders, S.; Stringer, R.; Ivanov, A.; Makouski, M.; Skhirtladze, N.; Taylor, R.; Anderson, I.; Fehling, D.; Gritsan, A.; Maksimovic, P.; Martin, C.; Nash, K.; Osherson, M.; Swartz, M.; Xiao, M.; Acosta, J.G.; Cremaldi, L.M.; Oliveros, S.; Perera, L.; Summers, D.; Bloom, K.; Bose, S.; Claes, D.R.; Dominguez, A.; Fangmeier, C.; Gonzalez Suarez, R.; Meier, F.; Monroy, J.; Hahn, K.; Sevova, S.; Sung, K.; Trovato, M.; Bartz, E.; Duggan, D.; Halkiadakis, E.; Lath, A.; Park, M.; Schnetzer, S.; Stone, R.; Walker, M.; Malik, S.; Mendez, H.; Ramirez Vargas, J.E.; Alyari, M.; Dolen, J.; George, J.; Godshalk, A.; Iashvili, I.; Kaisen, J.; Kharchilava, A.; Kumar, A.; Rappoccio, S.; Alexander, J.; Chaves, J.; Chu, J.; Dittmer, S.; Kaufman, G.; Mirman, N.; Ryd, A.; Salvati, E.; Skinnari, L.; Thom, J.; Thompson, J.; Tucker, J.; Winstrom, L.; Akgun, B.; Ecklund, K.M.; Nussbaum, T.; Zabel, J.; Betchart, B.; Demina, R.; Hindrichs, O.; Petrillo, G.; Eusebi, R.; Osipenkov, I.; Perloff, A.; Ulmer, K.A.; Delannoy, A.G.; D'Angelo, P.; Johns, W.

    2015-01-01

    The response of n+p silicon strip sensors to electrons from a Sr-90 source was measured using a multi-channel read-out system with 25 ns sampling time. The measurements were performed over a period of several weeks, during which the operating conditions were varied. The sensors were fabricated by Hamamatsu Photonics K.K. on 200 micrometer thick float-zone and magnetic-Czochralski silicon. Their pitch was 80 micrometer, and both p-stop and p-spray isolation of the n+ strips were studied. The electrons from the Sr-90 source were collimated to a spot with a full-width-at-half-maximum of 2 mm at the sensor surface, and the dose rate in the SiO2 at the maximum was about 50 Gy/d. After only a few hours of making measurements, significant changes in charge collection and charge sharing were observed. Annealing studies, with temperatures up to 80{\\deg}C and annealing times of 18 hours, showed that the changes can only be partially annealed. The observations can be qualitatively explained by the increase of the positi...

  18. Driver behavior profiling: An investigation with different smartphone sensors and machine learning

    National Research Council Canada - National Science Library

    Jair Ferreira Júnior; Eduardo Carvalho; Bruno V Ferreira; Cleidson de Souza; Yoshihiko Suhara; Alex Pentland; Gustavo Pessin

    2017-01-01

    .... This paper presents an investigation with different Android smartphone sensors, and classification algorithms in order to assess which sensor/method assembly enables classification with higher performance...

  19. A novel approach for honey pollen profile assessment using an electronic tongue and chemometric tools

    Energy Technology Data Exchange (ETDEWEB)

    Dias, Luís G., E-mail: ldias@ipb.pt [Escola Superior Agrária, Instituto Politécnico de Bragança, Campus Santa Apolónia, 5301-855 Bragança (Portugal); CQ-VR, Centro de Química – Vila Real, University of Trás-os-Montes e Alto Douro, Apartado 1013, 5001-801 Vila Real (Portugal); Veloso, Ana C.A. [Instituto Politécnico de Coimbra, ISEC, DEQB, Rua Pedro Nunes, Quinta da Nora, 3030-199 Coimbra (Portugal); CEB-Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga (Portugal); Sousa, Mara E.B.C.; Estevinho, Letícia [CIMO-Escola Superior Agrária, Instituto Politécnico de Bragança, Campus Santa Apolónia, 5301-855 Bragança (Portugal); Machado, Adélio A.S.C. [LAQUIPAI – Laboratório de Química Inorgânica Pura e de Aplicação Interdisciplinar, Departamento de Química, Faculdade de Ciências da, Universidade do Porto, Rua Campo Alegre n°. 687, 4169-007 Porto (Portugal); and others

    2015-11-05

    Nowadays the main honey producing countries require accurate labeling of honey before commercialization, including floral classification. Traditionally, this classification is made by melissopalynology analysis, an accurate but time-consuming task requiring laborious sample pre-treatment and high-skilled technicians. In this work the potential use of a potentiometric electronic tongue for pollinic assessment is evaluated, using monofloral and polyfloral honeys. The results showed that after splitting honeys according to color (white, amber and dark), the novel methodology enabled quantifying the relative percentage of the main pollens (Castanea sp., Echium sp., Erica sp., Eucaliptus sp., Lavandula sp., Prunus sp., Rubus sp. and Trifolium sp.). Multiple linear regression models were established for each type of pollen, based on the best sensors' sub-sets selected using the simulated annealing algorithm. To minimize the overfitting risk, a repeated K-fold cross-validation procedure was implemented, ensuring that at least 10–20% of the honeys were used for internal validation. With this approach, a minimum average determination coefficient of 0.91 ± 0.15 was obtained. Also, the proposed technique enabled the correct classification of 92% and 100% of monofloral and polyfloral honeys, respectively. The quite satisfactory performance of the novel procedure for quantifying the relative pollen frequency may envisage its applicability for honey labeling and geographical origin identification. Nevertheless, this approach is not a full alternative to the traditional melissopalynologic analysis; it may be seen as a practical complementary tool for preliminary honey floral classification, leaving only problematic cases for pollinic evaluation. - Highlights: • Honey's floral origin labeling is a legal requirement. • Melissopalynology analysis usually used to evaluate pollens profile is laborious. • A novel E-tongue based approach is applied to assess pollens

  20. ANN Modeling of Electronic Nose Based on Co-doped SnO2 Nanofiber Sensor

    Directory of Open Access Journals (Sweden)

    S. KHALDI

    2016-05-01

    Full Text Available We present in this paper a novel neural network based technique to create a model incorporates intelligence for electronic nose. The idea is to create intelligent models; the first one, called selector, can select exactly the nature of gas detected. The second intelligent model is a corrector, which can automatically compensate the electronic nose’s response characteristics and discriminating exactly the detected gas (nature and concentration, and make the response increases all time when the temperature increases. The electronic nose is based on Co-doped SnO2 nanofiber sensor. The MATLAB environment is used during the design phase and optimization. The method discriminates qualitatively and quantitatively between six gases. The advantage of the method is that it uses a small representative database so we can easily implement the model in an electrical simulator.

  1. Two dimensional, electronic particle tracking in liquids with a graphene-based magnetic sensor array

    Science.gov (United States)

    Neumann, Rodrigo F.; Engel, Michael; Steiner, Mathias

    2016-07-01

    nanoparticles in the liquid with high accuracy and (b) the reconstruction of a particle's flow-driven trajectory across the integrated sensor array with sub-pixel precision as a function of time, in what we call the ``Magnetic nanoparticle velocimetry'' technique. Since the method does not rely on optical detection, potential lab-on-chip applications include particle tracking and flow analysis in opaque media at the sub-micron scale. Electronic supplementary information (ESI) available: Movie that illustrates the reconstruction of particle trajectories and additional results to be used as a guideline for the choice of operational parameters such as nanoparticle diameter, nanoparticle concentration and magnetic field components. See DOI: 10.1039/C6NR03434A

  2. A spectral profile multiplexed FBG sensor network with application to strain measurement in a Kevlar woven fabric

    Science.gov (United States)

    Guo, Guodong; Hackney, Drew; Pankow, Mark; Peters, Kara

    2017-04-01

    A spectral profile division multiplexed fiber Bragg grating (FBG) sensor network is described in this paper. The unique spectral profile of each sensor in the network is identified as a distinct feature to be interrogated. Spectrum overlap is allowed under working conditions. Thus, a specific wavelength window does not need to be allocated to each sensor as in a wavelength division multiplexed (WDM) network. When the sensors are serially connected in the network, the spectrum output is expressed through a truncated series. To track the wavelength shift of each sensor, the identification problem is transformed to a nonlinear optimization problem, which is then solved by a modified dynamic multi-swarm particle swarm optimizer (DMS-PSO). To demonstrate the application of the developed network, a network consisting of four FBGs was integrated into a Kevlar woven fabric, which was under a quasi-static load imposed by an impactor head. Due to the substantial radial strain in the fabric, the spectrums of different FBGs were found to overlap during the loading process. With the developed interrogating method, the overlapped spectrum would be distinguished thus the wavelength shift of each sensor can be monitored.

  3. A Dew Point Meter Comprising a Nanoporous Thin Film Alumina Humidity Sensor with a Linearizing Capacitance Measuring Electronics

    Directory of Open Access Journals (Sweden)

    Dilip Kumar Ghara

    2008-02-01

    Full Text Available A novel trace moisture analyzer is presented comprising a capacitive nanoporous film of metal oxide sensor and electronics. The change in capacity of the sensor is due to absorption of water vapor by the pores. A simple capacitance measuring electronics is developed which can detect any change in capacitance and correlates to ambient humidity. The circuit can minimize the parasitic earth capacitance. The non linear response of the sensor is linearized with a micro-controller linearizing circuit. The experimental result shows a resolution of -4°C DP and accuracy within 2%.

  4. Molecular modeling of interactions in electronic nose sensors for environmental monitoring

    Science.gov (United States)

    Shevade, A. V.; Ryan, M. A.; Homer, M. L.; Manfreda, A. M.; Yen, S. -P. S.; Zhou, H.; Manatt, K.

    2002-01-01

    We report a study aimed at understanding analyte interactions with sensors made from polymer-carbon black composite films. The sensors are used in an Electronic Nose (ENose) which is used for monitoring the breathing air quality in human habitats. The model mimics the experimental conditions of the composite film deposition and formation and was developed using molecular modeling and simulation tools. The Dreiding 2.21 Force Field was used for the polymer and analyte molecules while graphite parameters were assigned to the carbon black atoms. The polymer considered for this work is methyl vinyl ether / maleic acid copolymer. The target analytes include both inorganic (NH3) and organic (methanol) types of compound. Results indicate different composite-analyte interaction behavior.

  5. One-Port Electronic Detection Strategies for Improving Sensitivity in Piezoelectric Resonant Sensor Measurements

    Directory of Open Access Journals (Sweden)

    Zhongxu Hu

    2016-10-01

    Full Text Available This paper describes a one-port mechanical resonance detection scheme utilized on a piezoelectric thin film driven silicon circular diaphragm resonator and discusses the limitations to such an approach in degenerate mode mass detection sensors. The sensor utilizes degenerated vibration modes of a radial symmetrical microstructure thereby providing both a sense and reference mode allowing for minimization of environmental effects on performance. The circular diaphragm resonator was fabricated with thickness of 4.5 µm and diameter of 140 µm. A PZT thin film of 0.75 µm was patterned on the top surface for the purposes of excitation and vibration sensing. The device showed a resonant frequency of 5.8 MHz for the (1, 1 mode. An electronic interface circuit was designed to cancel out the large static and parasitic capacitance allowing for electrical detection of the mechanical vibration thereby enabling the frequency split between the sense and reference mode to be measured accurately. The extracted motional current, proportional to the vibration velocity, was fed back to the drive to effectively increase the Q factor, and therefore device sensitivity, by more than a factor of 8. A software phase-locked loop was implemented to automatically track the resonant frequencies to allow for faster and accurate resonance detection. Results showed that by utilizing the absolute mode frequencies as an indication of sensor temperature, the variation in sensor temperature due to the heating from the drive electronics was accounted for and led to an ultimate measurement sensitivity of 2.3 Hz.

  6. Flexible MEMS: A novel technology to fabricate flexible sensors and electronics

    Science.gov (United States)

    Tu, Hongen

    This dissertation presents the design and fabrication techniques used to fabricate flexible MEMS (Micro Electro Mechanical Systems) devices. MEMS devices and CMOS(Complementary Metal-Oxide-Semiconductor) circuits are traditionally fabricated on rigid substrates with inorganic semiconductor materials such as Silicon. However, it is highly desirable that functional elements like sensors, actuators or micro fluidic components to be fabricated on flexible substrates for a wide variety of applications. Due to the fact that flexible substrate is temperature sensitive, typically only low temperature materials, such as polymers, metals, and organic semiconductor materials, can be directly fabricated on flexible substrates. A novel technology based on XeF2(xenon difluoride) isotropic silicon etching and parylene conformal coating, which is able to monolithically incorporate high temperature materials and fluidic channels, was developed at Wayne State University. The technology was first implemented in the development of out-of-plane parylene microneedle arrays that can be individually addressed by integrated flexible micro-channels. These devices enable the delivery of chemicals with controlled temporal and spatial patterns and allow us to study neurotransmitter-based retinal prosthesis. The technology was further explored by adopting the conventional SOI-CMOS processes. High performance and high density CMOS circuits can be first fabricated on SOI wafers, and then be integrated into flexible substrates. Flexible p-channel MOSFETs (Metal-Oxide-Semiconductor Field-Effect-Transistors) were successfully integrated and tested. Integration of pressure sensors and flow sensors based on single crystal silicon has also been demonstrated. A novel smart yarn technology that enables the invisible integration of sensors and electronics into fabrics has been developed. The most significant advantage of this technology is its post-MEMS and post-CMOS compatibility. Various high

  7. An Improved Ozone Profile Algorithm for the Airborne GeoTASO Sensor

    Science.gov (United States)

    Kurosu, T. P.; Natraj, V.; Neu, J. L.

    2016-12-01

    The Geostationary Trace gas and Aerosol Sensor Optimization (GeoTASO) is an airborne UV/Visible CCD spectrometer that was developed in support of the upcoming US TEMPO EV-I mission. The GeoTASO instrument consists of two channels that cover the spectral ranges of 290-300 nm and 415-695 nm with 0.28-0.49 nm (UV) and 0.56-0.98 nm (Vis) spectral resolution. At a typical flight altitude of 11 km, the 45° field of view results in a 9 km wide swath sub-divided into 1000 cross-track pixels. The instantaneous field of view records ground pixels of 50-80 m along-track, depending on detector integration time and aircraft speed relative to ground. GeoTASO observation targets include ozone, SO2, NO2, H2CO, C2H2O2, and aerosols. As part of the GEO-CAPE project, JPL has been developing retrieval algorithms for NO2 columns and ozone profiles from GeoTASO observations. The retrieval approach combines state-of-the-art non-linear least squares minimization techniques with new developments in fast radiative transfer that eliminates the need for tabulated air mass factors. We present first results of our retrievals of ozone profiles, NO2 columns, and interfering species, from GeoTASO observations acquired during the 2014 Denver flight campaign. We investigate the impact of combined UV/Visible multi-band spectral fitting approaches on the performance of the ozone profile retrieval, and their potential for application to geostationary observations.

  8. In-air fluence profiles and water depth dose for uncollimated electron beams

    Science.gov (United States)

    Toutaoui, Abedelkadar; Aichouche, Amar Nassim; Adjidir, Kenza Adjidir; Chami, Ahmed Chafik

    2008-01-01

    Advanced electron beam dose calculation models for radiation treatment planning systems require the input of a phase space beam model to configure a clinical electron beam in a computer. This beam model is a distribution in position, energy, and direction of electrons and photons in a plane in front of the patient. The phase space beam model can be determined by Monte Carlo simulation of the treatment head or from a limited set of measurements. In the latter case, parameters of the electron phase space beam model are obtained by fitting measured to calculated dosimetric data. In the present work, data for air fluence profiles and water depth doses have been presented for electron beams without an applicator for a medical linear accelerator. These data are used to parameterize the electron phase space beam model to a Monte Carlo dose calculation module available in the first commercial (MDS Nordion, now Nucletron) Monte Carlo treatment planning for electron beams. PMID:19893707

  9. Installation Status of the Electron Beam Profiler for the Fermilab Main Injector

    Energy Technology Data Exchange (ETDEWEB)

    Thurman-Keup, R.; Alvarez, M.; Fitzgerald, J.; Lundberg, C.; Prieto, P.; Roberts, M.; Zagel, J.; Blokland, W.

    2015-11-06

    The planned neutrino program at Fermilab requires large proton beam intensities in excess of 2 MW. Measuring the transverse profiles of these high intensity beams is challenging and often depends on non-invasive techniques. One such technique involves measuring the deflection of a probe beam of electrons with a trajectory perpendicular to the proton beam. A device such as this is already in use at the Spallation Neutron Source at ORNL and the installation of a similar device is underway in the Main Injector at Fermilab. The present installation status of the electron beam profiler for the Main Injector will be discussed together with some simulations and test stand results.

  10. Electron beam diagnostic for profiling high power beams

    Science.gov (United States)

    Elmer, John W [Danville, CA; Palmer, Todd A [Livermore, CA; Teruya, Alan T [Livermore, CA

    2008-03-25

    A system for characterizing high power electron beams at power levels of 10 kW and above is described. This system is comprised of a slit disk assembly having a multitude of radial slits, a conducting disk with the same number of radial slits located below the slit disk assembly, a Faraday cup assembly located below the conducting disk, and a start-stop target located proximate the slit disk assembly. In order to keep the system from over-heating during use, a heat sink is placed in close proximity to the components discussed above, and an active cooling system, using water, for example, can be integrated into the heat sink. During use, the high power beam is initially directed onto a start-stop target and after reaching its full power is translated around the slit disk assembly, wherein the beam enters the radial slits and the conducting disk radial slits and is detected at the Faraday cup assembly. A trigger probe assembly can also be integrated into the system in order to aid in the determination of the proper orientation of the beam during reconstruction. After passing over each of the slits, the beam is then rapidly translated back to the start-stop target to minimize the amount of time that the high power beam comes in contact with the slit disk assembly. The data obtained by the system is then transferred into a computer system, where a computer tomography algorithm is used to reconstruct the power density distribution of the beam.

  11. MOS-FET as a Current Sensor in Power Electronics Converters

    Directory of Open Access Journals (Sweden)

    Rok Pajer

    2015-07-01

    Full Text Available This paper presents a current sensing principle appropriate for use in power electronics’ converters. This current measurement principle has been developed for metal oxide semiconductor field effect transistor (MOS-FET and is based on UDS voltage measurement. In practice, shunt resistors and Hall effect sensors are usually used for these purposes, but the presented principle has many advantages. There is no need for additional circuit elements within high current paths, causing parasitic inductances and increased production complexity. The temperature dependence of MOS-FETs conductive resistance RDS−ON is considered in order to achieve the appropriate measurement accuracy. The “MOS-FET sensor” is also accompanied by a signal acquisition electronics circuit with an appropriate frequency bandwidth. The obtained analogue signal is therefore interposed to an A-D converter for further data acquisition. In order to achieve sufficient accuracy, a temperature compensation and appropriate approximation is used (RDS−ON = RDS−ON(Vj. The MOS-FET sensor is calibrated according to a reference sensor based on the Hall-effect principle. The program algorithm is executed on 32-bit ARM M4 MCU, STM32F407.

  12. NOAA JPSS Ozone Mapping and Profiler Suite (OMPS) Nadir Profile Science Sensor Data Record (SDR) from IDPS

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Ozone Mapping and Profiler Suite (OMPS) onboard the Suomi-NPP satellite monitors ozone from space. OMPS will collect total column and vertical profile ozone data...

  13. Classification of Mixtures of Odorants from Livestock Buildings by a Sensor Array (an Electronic Tongue

    Directory of Open Access Journals (Sweden)

    Jens Jørgen Lønsmann Iversen

    2007-01-01

    Full Text Available An electronic tongue comprising different numbers of electrodes was able to classify test mixtures of key odorants characteristic of bioscrubbers of livestock buildings (n-butyrate, iso-valerate, phenolate, p-cresolate, skatole and ammonium. The classification of model solutions indicates that the electronic tongue has a promising potential as an on- line sensor for characterization of odorants in livestock buildings. Back propagation artificial neural network was used for classification. The average classification rate was above 80% in all cases. A limited, but sufficient number of electrodes were selected by average classification rate and relative entropy. The sufficient number of electrodes decreased standard deviation and relative standard deviation compared to the full electrode array.

  14. Classification of Mixtures of Odorants from Livestock Buildings by a Sensor Array (an Electronic Tongue)

    Science.gov (United States)

    Abu-Khalaf, Nawaf; Iversen, Jens Jørgen Lønsmann

    2007-01-01

    An electronic tongue comprising different numbers of electrodes was able to classify test mixtures of key odorants characteristic of bioscrubbers of livestock buildings (n-butyrate, iso-valerate, phenolate, p-cresolate, skatole and ammonium). The classification of model solutions indicates that the electronic tongue has a promising potential as an online sensor for characterization of odorants in livestock buildings. Back propagation artificial neural network was used for classification. The average classification rate was above 80% in all cases. A limited, but sufficient number of electrodes were selected by average classification rate and relative entropy. The sufficient number of electrodes decreased standard deviation and relative standard deviation compared to the full electrode array.

  15. Self-Healing, Highly Sensitive Electronic Sensors Enabled by Metal-Ligand Coordination and Hierarchical Structure Design.

    Science.gov (United States)

    Han, Yangyang; Wu, Xiaodong; Zhang, Xinxing; Lu, Canhui

    2017-06-14

    Electronic sensors capable of capturing mechanical deformation are highly desirable for the next generation of artificial intelligence products. However, it remains a challenge to prepare self-healing, highly sensitive, and cost-efficient sensors for both tiny and large human motion monitoring. Here, a new kind of self-healing, sensitive, and versatile strain sensors has been developed by combining metal-ligand chemistry with hierarchical structure design. Specifically, a self-healing and nanostructured conductive layer is deposited onto a self-healing elastomer substrate cross-linked by metal-ligand coordinate bonds, forming a hierarchically structured sensor. The resultant sensors exhibit high sensitivity, low detection limit (0.05% strain), remarkable self-healing capability, as well as excellent reproducibility. Notably, the self-healed sensors are still capable to precisely capture not only tiny physiological activities (such as speech, swallowing, and coughing) but also large human motions (finger and neck bending, touching). Moreover, harsh treatments, including bending over 50000 times and mechanical washing, could not influence the sensitivity and stability of the self-healed sensors in human motion monitoring. This proposed strategy via alliance of metal-ligand chemistry and hierarchical structure design represents a general approach to manufacturing self-healing, robust sensors, and other electronic devices.

  16. Validation of COSMIC radio occultation electron density profiles by incoherent scatter radar data

    Science.gov (United States)

    Cherniak, Iurii; Zakharenkova, Irina

    The COSMIC/FORMOSAT-3 is a joint US/Taiwan radio occultation mission consisting of six identical micro-satellites. Each microsatellite has a GPS Occultation Experiment payload to operate the ionospheric RO measurements. FS3/COSMIC data can make a positive impact on global ionosphere study providing essential information about height electron density distribu-tion. For correct using of the RO electron density profiles for geophysical analysis, modeling and other applications it is necessary to make validation of these data with electron density distributions obtained by another measurement techniques such as proven ground based facili-ties -ionosondes and IS radars. In fact as the ionosondes provide no direct information on the profile above the maximum electron density and the topside ionosonde profile is obtained by fitting a model to the peak electron density value, the COSMIC RO measurements can make an important contribution to the investigation of the topside part of the ionosphere. IS radars provide information about the whole electron density profile, so we can estimate the agreement of topside parts between two independent measurements. To validate the reliability of COS-MIC data we have used the ionospheric electron density profiles derived from IS radar located near Kharkiv, Ukraine (geographic coordinates: 49.6N, 36.3E, geomagnetic coordinates: 45.7N, 117.8E). The Kharkiv radar is a sole incoherent scatter facility on the middle latitudes of Eu-ropean region. The radar operates with 100-m zenith parabolic antenna at 158 MHz with peak transmitted power 2.0 MW. The Kharkiv IS radar is able to determine the heights-temporal distribution of ionosphere parameters in height range of 70-1500 km. At the ionosphere in-vestigation by incoherent scatter method there are directly measured the power spectrum (or autocorrelation function) of scattered signal. With using of rather complex procedure of the received signal processing it is possible to estimate the

  17. Experimental Study on Rebar Corrosion Using the Galvanic Sensor Combined with the Electronic Resistance Technique

    Directory of Open Access Journals (Sweden)

    Yunze Xu

    2016-09-01

    Full Text Available In this paper, a new kind of carbon steel (CS and stainless steel (SS galvanic sensor system was developed for the study of rebar corrosion in different pore solution conditions. Through the special design of the CS and SS electronic coupons, the electronic resistance (ER method and zero resistance ammeter (ZRA technique were used simultaneously for the measurement of both the galvanic current and the corrosion depth. The corrosion processes in different solution conditions were also studied by linear polarization resistance (LPR and the measurements of polarization curves. The test result shows that the galvanic current noise can provide detailed information of the corrosion processes. When localized corrosion occurs, the corrosion rate measured by the ER method is lower than the real corrosion rate. However, the value measured by the LPR method is higher than the real corrosion rate. The galvanic current and the corrosion current measured by the LPR method shows linear correlation in chloride-containing saturated Ca(OH2 solution. The relationship between the corrosion current differences measured by the CS electronic coupons and the galvanic current between the CS and SS electronic coupons can also be used to evaluate the localized corrosion in reinforced concrete.

  18. Experimental Study on Rebar Corrosion Using the Galvanic Sensor Combined with the Electronic Resistance Technique

    Science.gov (United States)

    Xu, Yunze; Li, Kaiqiang; Liu, Liang; Yang, Lujia; Wang, Xiaona; Huang, Yi

    2016-01-01

    In this paper, a new kind of carbon steel (CS) and stainless steel (SS) galvanic sensor system was developed for the study of rebar corrosion in different pore solution conditions. Through the special design of the CS and SS electronic coupons, the electronic resistance (ER) method and zero resistance ammeter (ZRA) technique were used simultaneously for the measurement of both the galvanic current and the corrosion depth. The corrosion processes in different solution conditions were also studied by linear polarization resistance (LPR) and the measurements of polarization curves. The test result shows that the galvanic current noise can provide detailed information of the corrosion processes. When localized corrosion occurs, the corrosion rate measured by the ER method is lower than the real corrosion rate. However, the value measured by the LPR method is higher than the real corrosion rate. The galvanic current and the corrosion current measured by the LPR method shows linear correlation in chloride-containing saturated Ca(OH)2 solution. The relationship between the corrosion current differences measured by the CS electronic coupons and the galvanic current between the CS and SS electronic coupons can also be used to evaluate the localized corrosion in reinforced concrete. PMID:27618054

  19. A Study of Various Electronic Security Sensors Devices and Technology at Various Application Field Accompanied With Real Time Project Implementation of Sensor

    OpenAIRE

    Vijay Laxmi Kalyani; Parmeet Kour; Peram Navya

    2016-01-01

    Abstract: Nowadays electronics is everywhere and we are surrounded with electronic gazettes many of them are helping us in maintaining security at various places, there are many security problems faced by banks, homes etc. Without proper and strong security a vault can be penetrated. A security system is used in residential, commercial, industrial, Medical and Militaries as well as personal protection. In this paper we are discussing about the various electronic security sensor devices and te...

  20. Low-latitude Model Electron Density Profiles using the IRI and CCIR ...

    African Journals Online (AJOL)

    ... electron density profiles under different solar-geophysical conditions are highlighted. The need for additional ionosonde stations in the African sector in order to incorporate the results of studies on equatorial anomaly into the models is emphasized. Nigeria Journal of Pure and Applied Physics VOLUME 1, AUGUST 2000, ...

  1. Electronic detection of Drechslera sp. fungi in charentais melon ( Cucumis melo Naudin) using carbon-nanostructure-based sensors.

    Science.gov (United States)

    Greenshields, Márcia W C C; Mamo, Messai A; Coville, Neil J; Spina, Andréa P; Rosso, Diogo Filipe; Latocheski, Elaine C; Destro, João Guilherme; Pimentel, Ida C; Hümmelgen, Ivo A

    2012-10-24

    The development of chemical sensor technology in recent years has stimulated an interest regarding the use of characteristic volatiles and odors as a rapid and early indication of deterioration in fruit quality. The fungal infestation by Drechslera sp. in melons is a severe problem, and we demonstrate that electronic sensors based on carbon nanostructures are able to detect the presence of these fungi in melon. The responses of sensor conductance G and capacitance C at 27 kHz were measured and used to calculate their ΔG and ΔC variation over the full melon ripening process under shelf conditions with proliferation of Drechslera sp. fungi. The sensor response showed that these fungi can be electronically identified in charentais melon, constituting an effective and cheap test procedure to differentiate between infected and uninfected melon.

  2. Using an automatic resistivity profiler soil sensor on-the-go in precision viticulture.

    Science.gov (United States)

    Rossi, Roberta; Pollice, Alessio; Diago, Maria-Paz; Oliveira, Manuel; Millan, Borja; Bitella, Giovanni; Amato, Mariana; Tardaguila, Javier

    2013-01-16

    Spatial information on vineyard soil properties can be useful in precision viticulture. In this paper a combination of high resolution soil spatial information of soil electrical resistivity (ER) and ancillary topographic attributes, such as elevation and slope, were integrated to assess the spatial variability patterns of vegetative growth and yield of a commercial vineyard (Vitis vinifera L. cv. Tempranillo) located in the wine-producing region of La Rioja, Spain. High resolution continuous geoelectrical mapping was accomplished by an Automatic Resistivity Profiler (ARP) on-the-go sensor with an on-board GPS system; rolling electrodes enabled ER to be measured for a depth of investigation approximately up to 0.5, 1 and 2 m. Regression analysis and cluster analysis algorithm were used to jointly process soil resistivity data, landscape attributes and grapevine variables. ER showed a structured variability that matched well with trunk circumference spatial pattern and yield. Based on resistivity and a simple terrain attribute uniform management units were delineated. Once a spatial relationship to target variables is found, the integration of point measurement with continuous soil resistivity mapping is a useful technique to identify within-plots areas of vineyard with similar status.

  3. Using an Automatic Resistivity Profiler Soil Sensor On-The-Go in Precision Viticulture

    Directory of Open Access Journals (Sweden)

    Mariana Amato

    2013-01-01

    Full Text Available Spatial information on vineyard soil properties can be useful in precision viticulture. In this paper a combination of high resolution soil spatial information of soil electrical resistivity (ER and ancillary topographic attributes, such as elevation and slope, were integrated to assess the spatial variability patterns of vegetative growth and yield of a commercial vineyard (Vitis vinifera L. cv. Tempranillo located in the wine-producing region of La Rioja, Spain. High resolution continuous geoelectrical mapping was accomplished by an Automatic Resistivity Profiler (ARP on-the-go sensor with an on-board GPS system; rolling electrodes enabled ER to be measured for a depth of investigation approximately up to 0.5, 1 and 2 m. Regression analysis and cluster analysis algorithm were used to jointly process soil resistivity data, landscape attributes and grapevine variables. ER showed a structured variability that matched well with trunk circumference spatial pattern and yield. Based on resistivity and a simple terrain attribute uniform management units were delineated. Once a spatial relationship to target variables is found, the integration of point measurement with continuous soil resistivity mapping is a useful technique to identify within-plots areas of vineyard with similar status.

  4. Infrared single shot diagnostics for the longitudinal profile of the electron bunches at FLASH

    Energy Technology Data Exchange (ETDEWEB)

    Delsim-Hashemi, Hossein

    2008-09-15

    The longitudinal profile of electron bunches plays an important role in the design of single-pass free electron lasers and future linear e{sup +}e{sup -} colliders. For the free electron laser FLASH in Hamburg, a longitudinal compression scheme is used which results in an asymmetric longitudinal bunch profile with a 'spike'. This 'spike', which has a very high peak current, is used in a high-gain SASE-FEL process to produce high intensity (about 70 {mu}J) femtosecond photon pulses in the XUV wavelength range. The required high peak current of the electron bunch is realized by confining a large number of electrons in a width, measured in time units, of few tens of femtosecond, making the diagnostics of such bunches a challenge. Furthermore, the operation of facilities such as FLASH shows that single-shot diagnostics is indispensable. It is intuitive to use a time domain method to measure the electron bunch length. However, when the structures present in the bunch profile fall in the femtoseconds range, this is beyond the resolution of time-resolved methods developed so far. In this thesis, a wavelength-domain technique is described that can fulfill both requirements of single shot and high resolution reaching to the femtoseconds range. The amount of charge that is confined in a typical length of several femtoseconds (FWHM of the spike) can be determined by a novel single-shot spectrometer that resolves the coherent radiation (e.g. coherent transition radiation) in the far-infrared and mid-infrared range. Furthermore the extension of this single-shot spectroscopy to shorter wavelengths reaching the near-infrared, makes it possible to investigate the presence of structures in the bunch profile that might correlate or anti-correlate to the SASE intensity. (orig.)

  5. Variation Of Odour Profile Detected In The Floral Stages of Prunus Persica (L) Batsch Using An Electronic Nose

    Science.gov (United States)

    Valeria, Messina; Silvia, Radice; Rosa, Baby; de Reca Noemí, Walsöe

    2009-05-01

    Bees use signals from plants to identify worthwhile visits. They learn quickly to differentiate mainly their floral odor than their colour. In some species the flowers remain open, intact and turgid until they are pollinated (anthesis) after which they are no longer attractive to pollinators (post-anthesis). Pollinators use fragrance for distance orientation, approach, landing, feeding and associative learning. The aim of this work was to study the variation of odor profile between anthesis and post-anthesis produced in flowers of different cultivars of Prunus Persica (L.) batsch, using an electronic nose since odor is a communication between flowering plants and bees. Visual results on field showed that peach flowers are generally more visited in the anthesis stage. Among all the analysed cultivars, Forastero cultivar was the only one visited in this floral stage. Statistical analysis of the electronic nose data showed that doped semiconductuvtive SnO2 sensors could differentiate between stages (anthesis and post-anthesis) only in case of Forastero cultivar.

  6. Highly sensitive, self-powered and wearable electronic skin based on pressure-sensitive nanofiber woven fabric sensor.

    Science.gov (United States)

    Zhou, Yuman; He, Jianxin; Wang, Hongbo; Qi, Kun; Nan, Nan; You, Xiaolu; Shao, Weili; Wang, Lidan; Ding, Bin; Cui, Shizhong

    2017-10-11

    The wearable electronic skin with high sensitivity and self-power has shown increasing prospects for applications such as human health monitoring, robotic skin, and intelligent electronic products. In this work, we introduced and demonstrated a design of highly sensitive, self-powered, and wearable electronic skin based on a pressure-sensitive nanofiber woven fabric sensor fabricated by weaving PVDF electrospun yarns of nanofibers coated with PEDOT. Particularly, the nanofiber woven fabric sensor with multi-leveled hierarchical structure, which significantly induced the change in contact area under ultra-low load, showed combined superiority of high sensitivity (18.376 kPa-1, at ~100 Pa), wide pressure range (0.002-10 kPa), fast response time (15 ms) and better durability (7500 cycles). More importantly, an open-circuit voltage signal of the PPNWF pressure sensor was obtained through applying periodic pressure of 10 kPa, and the output open-circuit voltage exhibited a distinct switching behavior to the applied pressure, indicating the wearable nanofiber woven fabric sensor could be self-powered under an applied pressure. Furthermore, we demonstrated the potential application of this wearable nanofiber woven fabric sensor in electronic skin for health monitoring, human motion detection, and muscle tremor detection.

  7. A Physically Transient Form of Silicon Electronics, With Integrated Sensors, Actuators and Power Supply

    Science.gov (United States)

    Hwang, Suk-Won; Tao, Hu; Kim, Dae-Hyeong; Cheng, Huanyu; Song, Jun-Kyul; Rill, Elliott; Brenckle, Mark A.; Panilaitis, Bruce; Won, Sang Min; Kim, Yun-Soung; Yu, Ki Jun; Ameen, Abid; Li, Rui; Su, Yewang; Yang, Miaomiao; Kaplan, David L.; Zakin, Mitchell R.; Slepian, Marvin J.; Huang, Yonggang; Omenetto, Fiorenzo G.; Rogers, John A.

    2013-01-01

    A remarkable feature of modern silicon electronics is its ability to remain functionally and physically invariant, almost indefinitely for many practical purposes. Here, we introduce a silicon-based technology that offers the opposite behavior: it gradually vanishes over time, in a well-controlled, programmed manner. Devices that are ‘transient’ in this sense create application possibilities that cannot be addressed with conventional electronics, such as active implants that exist for medically useful timeframes, but then completely dissolve and disappear via resorption by the body. We report a comprehensive set of materials, manufacturing schemes, device components and theoretical design tools for a complementary metal oxide semiconductor (CMOS) electronics of this type, together with four different classes of sensors and actuators in addressable arrays, two options for power supply and a wireless control strategy. A transient silicon device capable of delivering thermal therapy in an implantable mode and its demonstration in animal models illustrate a system-level example of this technology. PMID:23019646

  8. A robust fibre laser system for electro-optic electron bunch profile measurements at FLASH

    Energy Technology Data Exchange (ETDEWEB)

    Wissmann, Laurens-Georg

    2012-08-15

    For the electro-optic measurement of electron bunch profiles at FLASH a robust ytterbium doped fibre laser (YDFL) system has been developed consisting of a laser oscillator and a two-staged amplifier. The oscillator is designed to meet the specifications of high reliability and low noise operation. The amplifier makes use of tailored nonlinearity to enhance the spectral bandwidth of the output laser pulses. Active repetition rate control enables sub-picosecond synchronisation of the laser to the accelerator reference RF. Using a two-stage gating scheme the output pulse train repetition rate is adopted to the accelerator repetition rate. An experimental site used for electro-optic electron bunch diagnostics has been redesigned to support single-shot bunch profile measurements based on spectral decoding. An existing bunch profile monitor with a similar laser system was upgraded and electro-optic bunch profile measurements were conducted, allowing for a comparison with measurements done with other longitudinal electron bunch diagnostics and with former measurements.

  9. High-sensitivity open-loop electronics for gravimetric acoustic-wave-based sensors.

    Science.gov (United States)

    Rabus, David; Friedt, Jean-Michel; Ballandras, Sylvain; Martin, Gilles; Carry, Emile; Blondeau-Patissier, Virginie

    2013-06-01

    Detecting chemical species in gas phase has recently received an increasing interest mainly for security control, trying to implement new systems allowing for extended dynamics and reactivity. In this work, an open-loop interrogation strategy is proposed to use radio-frequency acoustic transducers as micro-balances for that purpose. The resulting system is dedicated to the monitoring of chemical compounds in gaseous or liquid-phase state. A 16 Hz standard deviation is demonstrated at 125 MHz, with a working frequency band in the 60 to 133 MHz range, answering the requirements for using Rayleigh- and Love-wave-based delay lines operating with 40-μm acoustic wavelength transducers. Moreover, this electronic setup was used to interrogate a high-overtone bulk acoustic wave resonator (HBAR) microbalance, a new sensor class allowing for multi-mode interrogation for gravimetric measurement improvement. The noise source still limiting the system performance is due to the analog-to-digital converter of the microcontroller, thus leaving open degrees-of-freedom for improving the obtained results by optimizing the voltage reference and board layout. The operation of the system is illustrated using a calibrated galvanic deposition at the surface of Love-wave delay lines to assess theoretical predictions of their gravimetric sensitivity and to compare them with HBAR-based sensor sensitivity.

  10. 2nd Biennial Conference on Refrigeration for Cryogenic Sensors and Electronic Systems

    CERN Document Server

    1983-01-01

    This proceedings documents the output of the Second Biennial Conference on Refrigeration for Cryogenic Sensors and Electronic Systems held at the National Aeronautics and Space Administration's Goddard Space Flight Center, Greenbelt, Maryland, on December 7-8, 1982. Building on the first open meeting hosted by the National Bureau of Standards in 1980, the focus of this second meeting was again on low-temperature, closed-cycle cooler technology. However, higher temperature coolers (77 K), with technology applicable to the low temperature coolers, were considered to be within the scope of this meeting. This second conference consisted of 30 papers presented by representatives of industry, government, and academia. The conference proceedings reproduced here was published by the NASA Goddard Space Flight Center in Greenbelt Maryland as NASA Conference Publication 2287.

  11. Front-end electronics for the readout of CdZnTe sensors

    CERN Document Server

    Moraes, D; Rudge, A

    2006-01-01

    The CERN_DxCTA is a front-end ASIC optimized for the readout of CdZn Te sensors. The chip is implemented in 0.25 mum CMOS technology. The circuit consists of 128 channels equipped with a transimpedance amplifier followed by a gain-shaper stage with 20 ns peaking time and two discriminators, allowing two threshold settings. Each discriminator includes a 5-bit trim DAC and is followed by an 18-bit static ripple-counter. The channel architecture is optimized for the detector characteristics in order to achieve the best energy resolution at counting rates of up to 5 M counts/second. Complete evaluation of the circuit is presented using electronic pulses and Cd ZnTe pixel detectors.

  12. Electronic properties of NH4-adsorbed graphene nanoribbon as a promising candidate for a gas sensor

    Directory of Open Access Journals (Sweden)

    Naoki Harada

    2016-05-01

    Full Text Available The electronic properties of NH4-adsorbed N = 7 armchair graphene nanoribbons (AGNRs were theoretically investigated using self-consistent atomistic simulations to explore the feasibility of AGNRs as a gas sensing material. Whereas a pristine AGNR has a finite band gap and is an intrinsic semiconductor, an NH4-adsorbed AGNR exhibits heavily doped n-type properties similar to a graphene sheet with the molecules adsorbed. The electric characteristics of a back-gated AGNR gas sensor were also simulated and the drain current changed exponentially with increasing number of adsorbed molecules. We may conclude that an AGNR is promising as a highly sensitive gas-sensing material with large outputs.

  13. 14 GHz longitudinally detected electron spin resonance using microHall sensors

    Science.gov (United States)

    Bouterfas, M.; Mouaziz, S.; Popovic, R. S.

    2017-09-01

    In this work we developed a home-made LOngitudinally Detected Electron Spin Resonance (LODESR) spectrometer based on a microsize Hall sensor. A coplanar waveguide (CPW)-resonator is used to induce microwave-excitation on the sample at 14 GHz. We used InSb cross-shaped Hall devices with active areas of (10 μm × 10 μm) and (5 μm × 5 μm) . Signal intensities of the longitudinal magnetization component of DPPH and YIG samples of volumes about (10 μm) 3 and (5 μm) 3 , are measured under amplitude and frequency modulated microwave magnetic field generated by the CPW-resonator. At room temperature, 109spins /G √Hz sensitivity is achieved for 0.2mT linewidth, a result which is still better than most of inductive detected LODESR sensitivities.

  14. Net community production at Ocean Station Papa observed with nitrate and oxygen sensors on profiling floats

    Science.gov (United States)

    Plant, Joshua N.; Johnson, Kenneth S.; Sakamoto, Carole M.; Jannasch, Hans W.; Coletti, Luke J.; Riser, Stephen C.; Swift, Dana D.

    2016-06-01

    Six profiling floats equipped with nitrate and oxygen sensors were deployed at Ocean Station P in the Gulf of Alaska. The resulting six calendar years and 10 float years of nitrate and oxygen data were used to determine an average annual cycle for net community production (NCP) in the top 35 m of the water column. NCP became positive in February as soon as the mixing activity in the surface layer began to weaken, but nearly 3 months before the traditionally defined mixed layer began to shoal from its winter time maximum. NCP displayed two maxima, one toward the end of May and another in August with a summertime minimum in June corresponding to the historical peak in mesozooplankton biomass. The average annual NCP was determined to be 1.5 ± 0.6 mol C m-2 yr-1 using nitrate and 1.5 ± 0.7 mol C m-2 yr-1 using oxygen. The results from oxygen data proved to be quite sensitive to the gas exchange model used as well as the accuracy of the oxygen measurement. Gas exchange models optimized for carbon dioxide flux generally ignore transport due to gas exchange through the injection of bubbles, and these models yield NCP values that are two to three time higher than the nitrate-based estimates. If nitrate and oxygen NCP rates are assumed to be related by the Redfield model, we show that the oxygen gas exchange model can be optimized by tuning the exchange terms to reproduce the nitrate NCP annual cycle.

  15. Electron beam based transversal profile measurements of intense ion beams; Elektronenstrahl-Diagnostik zur Bestimmung vom transversalen Profil intensiver Ionenstrahlen

    Energy Technology Data Exchange (ETDEWEB)

    El Moussati, Said

    2014-11-03

    A non-invasive diagnostic method for the experimental determination of the transverse profile of an intense ion beam has been developed and investigated theoretically as well as experimentally within the framework of the present work. The method is based on the deflection of electrons when passing the electromagnetic field of an ion beam. To achieve this an electron beam is employed with a specifically prepared transversal profile. This distinguish this method from similar ones which use thin electron beams for scanning the electromagnetic field [Roy et al. 2005; Blockland10]. The diagnostic method presented in this work will be subsequently called ''Electron-Beam-Imaging'' (EBI). First of all the influence of the electromagnetic field of the ion beam on the electrons has been theoretically analyzed. It was found that the magnetic field causes only a shift of the electrons along the ion beam axis, while the electric field only causes a shift in a plane transverse to the ion beam. Moreover, in the non-relativistic case the magnetic force is significantly smaller than the Coulomb one and the electrons suffer due to the magnetic field just a shift and continue to move parallel to their initial trajectory. Under the influence of the electric field, the electrons move away from the ion beam axis, their resulting trajectory shows a specific angle compared to the original direction. This deflection angle practically depends just on the electric field of the ion beam. Thus the magnetic field has been neglected when analysing the experimental data. The theoretical model provides a relationship between the deflection angle of the electrons and the charge distribution in the cross section of the ion beam. The model however only can be applied for small deflection angles. This implies a relationship between the line-charge density of the ion beam and the initial kinetic energy of the electrons. Numerical investigations have been carried out to clarify the

  16. Temperature-dependent electronic decay profiles in CZT: probe of bulk and surface properties

    Science.gov (United States)

    Kessick, Royal; Maupin, Hugh; Tepper, Gary C.; Szeles, Csaba

    2003-01-01

    The electronic performance of CZT-based gamma radiation spectrometers is governed by a synergism of bulk and surface properties. Compensation is used to increase the bulk resistivity of Cd1-xZnxTe (x~0.1), but the same electronic states that are introduced to increase the material resistivity can also trap charge and reduce the carrier lifetime. Electrical and mechanical surface defects introduced during or subsequent to crystal harvesting are also known to interfere with device performance. Using a contactless, pulsed laser microwave cavity perturbation technique, electronic decay profiles were studied in high pressure Bridgman CZT as a function of temperature. The electronic decay profile was found to depend very strongly on temperature and was modeled using a function consisting of two exponential terms with temperature-dependent amplitudes and time constants. The model was used to relate the observed temperature dependent decay kinetics in CZT to specific trap energies. It was found that, at low temperatures, the electronic decay process is dominated by a deep trap with an energy of approximately 0.69 +/- 0.1 eV from the band edge. As the temperature is increased, the charge trapping becomes dominated by a second trap with an energy of approximately 0.60 +/- 0.1 eV from the band edge. Surface damage introduces additional charge traps that significantly alter the decay kinetics particularly at low temperatures.

  17. Modelling of the electron density height profiles in the mid-latitude ionospheric D-region

    Directory of Open Access Journals (Sweden)

    P. Y. Mukhtarov

    1996-06-01

    Full Text Available A new mid-latitude D-region (50-105 km model of the electron density is presented obtained on the basis of a full wave theory and by a trial-and-error inversion method. Daytime (at different solar zenith angles absorption measurements by A3-technique made in Bulgaria yielded data with the aid of which the seasonal and diurnal courses of the Ne(h-profiles were derived. Special attention is drawn to the event diurnal asymmetry, or uneven formation of the ionosphere as a function of insulation. The latter is probably connected with the influence of the diurnal fluctuations in the local temperature on the chemistry involved in the electron loss rate, as well as the diurnal variations of the main ionizing agent (NO in the D-region. That is why the Ne(h-profiles in the midlatitude D-region are modelled separately for morning and afternoon hours.

  18. Hot-Electron Tunneling sensors for high-resolution x-ray and gamma-ray spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Mears, C.A.; Labov, S.E.; Frank, M.; Netel, H.

    1997-02-07

    Over the past 2 years, we have been studying the use of Hot Electron Tunneling sensors for use in high-energy-resolution x-ray and gamma-ray spectrometers. These sensors promise several advantages over existing cryogenic sensors, including simultaneous high count rate and high resolution capability, and relative ease of use. Using simple shadow mask lithography, we verified the basic principles of operation of these devices and discovered new physics in their thermal behavior as a function applied voltage bias. We also began to develop ways to use this new sensor in practical x-ray and gamma-ray detectors based on superconducting absorbers. This requires the use of quasiparticle trapping to concentrate the signal in the sensing elements.

  19. The Impacts of Attitudes and Engagement on Electronic Word of Mouth (eWOM of Mobile Sensor Computing Applications

    Directory of Open Access Journals (Sweden)

    Yu Zhao

    2016-03-01

    Full Text Available As one of the latest revolutions in networking technology, social networks allow users to keep connected and exchange information. Driven by the rapid wireless technology development and diffusion of mobile devices, social networks experienced a tremendous change based on mobile sensor computing. More and more mobile sensor network applications have appeared with the emergence of a huge amount of users. Therefore, an in-depth discussion on the human–computer interaction (HCI issues of mobile sensor computing is required. The target of this study is to extend the discussions on HCI by examining the relationships of users’ compound attitudes (i.e., affective attitudes, cognitive attitude, engagement and electronic word of mouth (eWOM behaviors in the context of mobile sensor computing. A conceptual model is developed, based on which, 313 valid questionnaires are collected. The research discusses the level of impact on the eWOM of mobile sensor computing by considering user-technology issues, including the compound attitude and engagement, which can bring valuable discussions on the HCI of mobile sensor computing in further study. Besides, we find that user engagement plays a mediating role between the user’s compound attitudes and eWOM. The research result can also help the mobile sensor computing industry to develop effective strategies and build strong consumer user—product (brand relationships.

  20. The Impacts of Attitudes and Engagement on Electronic Word of Mouth (eWOM) of Mobile Sensor Computing Applications.

    Science.gov (United States)

    Zhao, Yu; Liu, Yide; Lai, Ivan K W; Zhang, Hongfeng; Zhang, Yi

    2016-03-18

    As one of the latest revolutions in networking technology, social networks allow users to keep connected and exchange information. Driven by the rapid wireless technology development and diffusion of mobile devices, social networks experienced a tremendous change based on mobile sensor computing. More and more mobile sensor network applications have appeared with the emergence of a huge amount of users. Therefore, an in-depth discussion on the human-computer interaction (HCI) issues of mobile sensor computing is required. The target of this study is to extend the discussions on HCI by examining the relationships of users' compound attitudes (i.e., affective attitudes, cognitive attitude), engagement and electronic word of mouth (eWOM) behaviors in the context of mobile sensor computing. A conceptual model is developed, based on which, 313 valid questionnaires are collected. The research discusses the level of impact on the eWOM of mobile sensor computing by considering user-technology issues, including the compound attitude and engagement, which can bring valuable discussions on the HCI of mobile sensor computing in further study. Besides, we find that user engagement plays a mediating role between the user's compound attitudes and eWOM. The research result can also help the mobile sensor computing industry to develop effective strategies and build strong consumer user-product (brand) relationships.

  1. Perpendicular hot electron spin-valve effect in a new magnetic field sensor: The spin-valve transistor

    NARCIS (Netherlands)

    Monsma, D.J.; Lodder, J.C.; Popma, T.J.A.; Dieny, B.

    1995-01-01

    A new magnetic field sensor is presented, based on perpendicular hot electron transport in a giant magnetoresistance (Co/Cu)4 multilayer, which serves as a base region of an n-silicon metal-base transistor structure. A 215% change in collector current is found in 500 Oe (77 K), with typical

  2. Power Dependence of the Electron Mobility Profile in a Hall Thruster

    Science.gov (United States)

    Jorns, Benjamin A.; Hofery, Richard H.; Mikellides, Ioannis G.

    2014-01-01

    The electron mobility profile is estimated in a 4.5 kW commercial Hall thruster as a function of discharge power. Internal measurements of plasma potential and electron temperature are made in the thruster channel with a high-speed translating probe. These measurements are presented for a range of throttling conditions from 150 - 400 V and 0.6 - 4.5 kW. The fluid-based solver, Hall2De, is used in conjunction with these internal plasma parameters to estimate the anomalous collision frequency profile at fixed voltage, 300 V, and three power levels. It is found that the anomalous collision frequency profile does not change significantly upstream of the location of the magnetic field peak but that the extent and magnitude of the anomalous collision frequency downstream of the magnetic peak does change with thruster power. These results are discussed in the context of developing phenomenological models for how the collision frequency profile depends on thruster operating conditions.

  3. Topside ionospheric vertical electron density profile reconstruction using GPS and ionosonde data: possibilities for South Africa

    Directory of Open Access Journals (Sweden)

    P. Sibanda

    2011-02-01

    Full Text Available Successful empirical modeling of the topside ionosphere relies on the availability of good quality measured data. The Alouette, ISIS and Intercosmos-19 satellite missions provided large amounts of topside sounder data, but with limited coverage of relevant geophysical conditions (e.g., geographic location, diurnal, seasonal and solar activity by each individual mission. Recently, methods for inferring the electron density distribution in the topside ionosphere from Global Positioning System (GPS-based total electron content (TEC measurements have been developed. This study is focused on the modeling efforts in South Africa and presents the implementation of a technique for reconstructing the topside ionospheric electron density (Ne using a combination of GPS-TEC and ionosonde measurements and empirically obtained Upper Transition Height (UTH. The technique produces reasonable profiles as determined by the global models already in operation. With the added advantage that the constructed profiles are tied to reliable measured GPS-TEC and the empirically determined upper transition height, the technique offers a higher level of confidence in the resulting Ne profiles.

  4. Nano-arrays of SAM by dip-pen nanowriting (DPN) technique for futuristic bio-electronic and bio-sensor applications

    Energy Technology Data Exchange (ETDEWEB)

    Agarwal, Pankaj B., E-mail: pankaj@ceeri.ernet.i [Central Electronics Engineering Research Institute, Pilani - 333 031, (Council of Scientific and Industrial Research, Delhi) (India); Kumar, A. [Central Electronics Engineering Research Institute, Pilani - 333 031, (Council of Scientific and Industrial Research, Delhi) (India); Saravanan, R. [Vellore Institute of Technology University, Vellore - 632 014 (India); Sharma, A.K.; Shekhar, Chandra [Central Electronics Engineering Research Institute, Pilani - 333 031, (Council of Scientific and Industrial Research, Delhi) (India)

    2010-11-30

    Nano-arrays of bio-molecules have potential applications in many areas namely, bio-sensors, bio/molecular electronics and virus detection. Spot array, micro-contact printing and photolithography are used for micron size array fabrications while Dip-Pen Nanowriting (DPN) is employed for submicron/nano size arrays. We have fabricated nano-dots of 16-MHA (16-mercaptohexadecanoic acid) self-assembled monolayer (SAM) on gold substrate by DPN technique with different dwell time under varying relative humidity. These patterns were imaged in the same system in LFM (Lateral Force Microscopy) mode with fast scanning speed (5 Hz). The effect of humidity on size variation of nano-dots has been studied. During experiments, relative humidity (RH) was varied from 20% to 60%, while the temperature was kept constant {approx} 25 {sup o}C. The minimum measured diameter of the dot is {approx} 294 nm at RH = 20% for a dwell time of 2 s. The thickness of the 16-MHA dots, estimated in NanoRule image analysis software is {approx} 2 nm, which agrees well with the length of single MHA molecule (2.2 nm). The line profile has been used to estimate the size and thickness of dots. The obtained results will be useful in further development of nano-array based bio-sensors and bio-electronic devices.

  5. Electron Profile Stiffness and Critical Gradient Length Studies in the Alcator C-Mod Tokamak

    Science.gov (United States)

    Houshmandyar, Saeid; Hatch, David R.; Liao, Kenneth T.; Zhao, Bingzhe; Phillips, Perry E.; Rowan, William L.; Cao, Norman; Ernst, Darin R.; Rice, John E.

    2017-10-01

    Electron temperature profile stiffness was investigated at Alcator C-Mod L-mode discharges. Electrons were heated by ion cyclotron range of frequencies (ICRF) through minority heating. The intent of the heating mechanism was to vary the heat flux and simultaneously, gradually change the local gradient. The electron temperature gradient scale length (LTe- 1 = | ∇Te |/Te) was accurately measured through a novel technique, using the high-resolution radiometer ECE diagnostic. The TRANSP power balance analysis (Q/QGB) and the measured scale length (a/LTe) result in critical scale length measurements at all major radius locations. These measurements suggest that the profiles are already at the critical values. Furthermore, the dependence of the stiffness on plasma rotation and magnetic shear will be discussed. In order to understand the underlying mechanism of turbulence for these discharges, simulations using the gyrokinetic code, GENE, were carried out. For linear runs at electron scales, it was found that the largest growth rates are very sensitive to a/LTe variation, which suggests the presence of ETG modes, while the sensitivity studies in the ion scales indicate ITG/TEM modes. Supported by USDoE awards DE-FG03-96ER54373 and DE-FC02-99ER54512.

  6. Proton transfer in phenol-amine complexes: phenol electronic effects on free energy profile in solution.

    Science.gov (United States)

    Aono, Shinji; Kato, Shigeki

    2010-12-01

    Free energy profiles for the proton transfer reactions in hydrogen-bonded complex of phenol with trimethylamine in methyl chloride solvent are studied with the reference interaction site model self-consistent field method. The reactions in both the electronic ground and excited states are considered. The second-order Møller-Plesset perturbation (MP) theory or the second-order multireference MP theory is used to evaluate the effect of the dynamical electron correlation on the free energy profiles. The free energy surface in the ground state shows a discrepancy with the experimental results for the related hydrogen-bonded complexes. To resolve this discrepancy, the effects of chloro-substitutions in phenol are examined, and its importance in stabilizing the ionic form is discussed. The temperature effect is also studied. In contrast to the ground state, the ππ* excited state of phenol-trimethylamine complex exhibits the proton transfer reaction with a low barrier. The reaction is almost thermoneutral. This is attributed to the reduction of proton affinity of phenol by the ππ* electronic excitation. We further examine the possibility of the electron-proton-coupled transfer in the ππ* state through the surface crossing with the charge transfer type πσ* state. © 2010 Wiley Periodicals, Inc.

  7. High-Performance Carbon Nanotube Complementary Electronics and Integrated Sensor Systems on Ultrathin Plastic Foil.

    Science.gov (United States)

    Zhang, Heng; Xiang, Li; Yang, Yingjun; Xiao, Mengmeng; Han, Jie; Ding, Li; Zhang, Zhiyong; Hu, Youfan; Peng, Lian-Mao

    2018-02-01

    The longtime vacancy of high-performance complementary metal-oxide-semiconductor (CMOS) technology on plastics is a non-negligible obstacle to the applications of flexible electronics with advanced functions, such as continuous health monitoring with in situ signal processing and wireless communication capabilities, in which high speed, low power consumption, and complex functionality are desired for integrated circuits (ICs). Here, we report the implementation of carbon nanotube (CNT)-based high-performance CMOS technology and its application for signal processing in an integrated sensor system for human body monitoring on ultrathin plastic foil with a thickness of 2.5 μm. The performances of both the p- and n-type CNT field-effect transistors (FETs) are excellent and symmetric on plastic foil with a low operation voltage of 2 V: width-normalized transconductances (g m /W) as high as 4.69 μS/μm and 5.45 μS/μm, width-normalized on-state currents reaching 5.85 μA/μm and 6.05 μA/μm, and mobilities up to 80.26 cm 2 ·V -1 ·s -1 and 97.09 cm 2 ·V -1 ·s -1 , respectively, together with a current on/off ratio of approximately 10 5 . The devices were mechanically robust, withstanding a curvature radius down to 124 μm. Utilizing these transistors, various high-performance CMOS digital ICs with rail-to-rail output and a ring oscillator on plastics with an oscillation frequency of 5 MHz were demonstrated. Furthermore, an ultrathin skin-mounted humidity sensor system with in situ frequency modulation signal processing capability was realized to monitor human body sweating.

  8. Effect of H- stripped electrons on the LINAC4 profile measurements

    CERN Document Server

    Chevallay, E; Duraffourg, M; Focker, GJ; Hessler, C; Raich, U; Roncarolo, F; Vuitton, C; Zocca, F

    2013-01-01

    At CERN's LINAC4 it is foreseen to measure transverse beam profiles by means of Secondary Emission wire grids (normally referred to as SEM monitors or SEM grids) and Beam Wire Scanners (BWS). Following observations at the SNS linac BWS, that showed cross-talk between wire signals attributed to scattering of H- stripped electrons, it was decided to investigate this effect for the LINAC4 case. The interaction of electron beams with Carbon and Tungsten wires was studied through Monte Carlo simulations (FLUKA code), analytical calculations, particle tracking simulations in EM fields (CST Particle Studio) and a laboratory experiment based on a 70 keV electron beam, well reproducing the case of 128 MeV H- ions.

  9. Conductive fiber-based ultrasensitive textile pressure sensor for wearable electronics.

    Science.gov (United States)

    Lee, Jaehong; Kwon, Hyukho; Seo, Jungmok; Shin, Sera; Koo, Ja Hoon; Pang, Changhyun; Son, Seungbae; Kim, Jae Hyung; Jang, Yong Hoon; Kim, Dae Eun; Lee, Taeyoon

    2015-04-17

    A flexible and sensitive textile-based pressure sensor is developed using highly conductive fibers coated with dielectric rubber materials. The pressure sensor exhibits superior sensitivity, very fast response time, and high stability, compared with previous textile-based pressure sensors. By using a weaving method, the pressure sensor can be applied to make smart gloves and clothes that can control machines wirelessly as human-machine interfaces. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Application of Tuning Fork Sensors for In-situ Studies of Dynamic Force Interactions Inside Scanning and Transmission Electron Microscopes

    Directory of Open Access Journals (Sweden)

    Jana ANDZANE

    2012-06-01

    Full Text Available Mechanical properties of nanoscale contacts have been probed in-situ by specially developed force sensor based on a quartz tuning fork resonator (TF. Additional control is provided by observation of process in scanning electron microscope (SEM and transmission electron microscope (TEM. A piezoelectric manipulator allows precise positioning of atomic force microscope (AFM probe in contact with another electrode and recording of the TF oscillation amplitude and phase while simultaneously visualizing the contact area in electron microscope. Electrostatic control of interaction between the electrodes is demonstrated during observation of the experiment in SEM. In the TEM system the TF sensor operated in shear force mode: Use of TEM allowed for direct control of separation between electrodes. New opportunities for in situ studies of nanomechanical systems using these instruments are discussed.DOI: http://dx.doi.org/10.5755/j01.ms.18.2.1927

  11. Embedding Piezoresistive Pressure Sensors to Obtain Online Pressure Profiles Inside Fiber Composite Laminates

    Directory of Open Access Journals (Sweden)

    Maryam Kahali Moghaddam

    2015-03-01

    Full Text Available The production of large and complex parts using fiber composite materials is costly due to the frequent formation of voids, porosity and waste products. By embedding different types of sensors and monitoring the process in real time, the amount of wastage can be significantly reduced. This work focuses on developing a knowledge-based method to improve and ensure complete impregnation of the fibers before initiation of the resin cure. Piezoresistive and capacitive pressure sensors were embedded in fiber composite laminates to measure the real-time the pressure values inside the laminate. A change of pressure indicates resin infusion. The sensors were placed in the laminate and the resin was infused by vacuum. The embedded piezoresistive pressure sensors were able to track the vacuum pressure in the fiber composite laminate setup, as well as the arrival of the resin at the sensor. The pressure increase due to closing the resin inlet was also measured. In contrast, the capacitive type of sensor was found to be inappropriate for measuring these quantities. The following study demonstrates real-time monitoring of pressure changes inside the fiber composite laminate, which validate the use of Darcy’s law in porous media to control the resin flow during infusion.

  12. Proton and electron deep dose profiles for retinoblastoma based on GEANT 4 code

    Energy Technology Data Exchange (ETDEWEB)

    Braga, Flavia V., E-mail: flaviafisica@gmail.co [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Programa de Pos-graduacao em Ciencias e Tecnicas Nucleares; Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Campos, Tarcisio P.R. de [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Programa de Pos-graduacao em Ciencias e Tecnicas Nucleares; Ribeiro, Kilder L., E-mail: kilderlr@gmail.co [Universidade Estadual de Feira de Santana (UEFS), BA (Brazil). Dept. de Fisica

    2009-07-01

    Herein, the dosimetry responses to a retinoblastoma proton and electron radiation therapy were investigated. The computational tool applied to this simulation was the Geant4 code, version 4.9.1. The code allows simulating the charge particle interaction with eyeball tissue. In the present simulation, a box of 4 cm side water filled had represented the human eye. The simulation was performed considering mono energetic beams of protons and electrons with spectra of 57 to 70 MeV for protons and 2 to 8 MeV for electrons. The simulation was guide by the advanced hadron therapy example distributed with the Geant4 code. The phantom was divided in voxels with 0.2 mm side. The energy deposited in each voxel was evaluated taken the direct beam at one face. The simulation results show the delivery energy and therefore the dose deposited in each voxel. The deep dose profiles to proton and electron were plotted. The well known Bragg peak was reproduced for protons. The maximum delivered dose defined the position at the proton stopped. However, to electrons, the absorbed energies were delivered along its path producing a more continuous distribution following the water depth, but also being stopped in the end of its path. (author)

  13. Studies of longitudinal profile of electron bunches and impedance measurements at Indus-2 synchrotron radiation source

    Energy Technology Data Exchange (ETDEWEB)

    Garg, Akash Deep, E-mail: akash-deep@rrcat.gov.in [Beam Diagnostics Section (BDS), Indus Operations, Beam Dynamics and Diagnostics Division (IOBDD), Raja Ramanna Centre for Advanced Technology, Indore 452 013, M.P. (India); Homi Bhabha National Institute (HBNI) at Raja Ramanna Centre for Advanced Technology, Indore (India); Yadav, S.; Kumar, Mukesh; Shrivastava, B.B.; Karnewar, A.K.; Ojha, A.; Puntambekar, T.A. [Beam Diagnostics Section (BDS), Indus Operations, Beam Dynamics and Diagnostics Division (IOBDD), Raja Ramanna Centre for Advanced Technology, Indore 452 013, M.P. (India)

    2016-04-01

    Indus-2 is a 3rd generation synchrotron radiation source at the Raja Ramanna Centre for Advanced Technology (RRCAT) in India. We study the longitudinal profile of electrons in Indus-2 by using dual sweep synchroscan streak camera at visible diagnostic beamline. In this paper, the longitudinal profiles of electron bunch are analyzed by filling beam current in a single bunch mode. These studies are carried at injection energy (550 MeV) and at ramped beam energy (2.5 GeV). The effects of the wakefield generated interactions between the circulating electrons and the surrounding vacuum chamber are analyzed in terms of measured effects on longitudinal beam distribution. The impedance of the storage ring is obtained by fitting the solutions of Haissinski equation to the measured bunch lengthening with different impedance models. The impedance of storage ring obtained by a series R+L impedance model indicates a resistance (R) of 1350±125 Ω, an inductance (L) of 180±25 nH and broadband impedance of 2.69 Ω. These results are also compared with the values obtained from measured synchronous phase advancing and scaling laws. These studies are very useful in better understanding and control of the electromagnetic interactions.

  14. Transition edge sensor system for material analysis using transmission electron microscope

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, K., E-mail: keiichi.tanaka@siint.co.j [SII NanoTechnology Inc., 36-1 Takkenoshita, Oyama-cho, Sunto-gun, Shizuoka 410-1393 (Japan); Odawara, A. [SII NanoTechnology Inc., 36-1 Takkenoshita, Oyama-cho, Sunto-gun, Shizuoka 410-1393 (Japan); Bandou, S. [Meijo University, 1-501 Shiogamaguchi, Tenpaku, Nagoya 468-8502 (Japan); Nagata, A.; Nakayama, S.; Chinone, K.; Yasaka, A. [SII NanoTechnology Inc., 36-1 Takkenoshita, Oyama-cho, Sunto-gun, Shizuoka 410-1393 (Japan); Koike, Y. [Taiyo Nippon Sanso Corp., Ohkubo 10, Tsukuba 300-2611 (Japan); Iijima, S. [Meijo University, 1-501 Shiogamaguchi, Tenpaku, Nagoya 468-8502 (Japan)

    2009-10-15

    We have developed a Transition Edge Sensor (TES) - Energy Dispersive Spectroscopy (EDS) for Transmission Electron Microscope (TEM) based on a dilution refrigerator. The dilution refrigerator was cooled by liquid helium (L-He), which was supplied from an L-He container separated from the dilution refrigerator. We adopted the hybrid magnetic shields combining a permalloy shield and a NbTi/Nb/Cu superconducting shield to operate the TEM-TES system under a magnetic field of 200 mT. The permalloy shield was used to prevent the ambient magnetic field until the NbTi superconducting shield cooled from room temperature (RT) to 2 K. The critical magnetic field was 220 mT for the TES change from a superconducting state to a normal state. The SQUID - current vs. bias current curve, under the condition that the snout was inserted in the TEM, was equal to the curve of the snout that was out of the TEM. The C (0 0 2) planes could be observed at 120 kV under the condition the snout was inserted in the TEM.

  15. Using electronic odor sensors to discriminate among oak barrel toasting levels.

    Science.gov (United States)

    Chatonnet, P; Dubourdieu, D

    1999-10-01

    Toasting changes both the quantity and the quality of the extractable substances in oak wood of barrels used for the aging of fine wines and spirits. Mastery and repeatability of toasting are vital in the production of quality barrels to be used for aging wines and spirits. Toasted wood components, which can be extracted by the wines or spirits during the aging process, are normally analyzed by maceration in standard alcohol solutions at concentrations adapted to the various products and can be used to control the intensity of the wood toasting. These kinds of analyses are accurate but time-consuming and need specialized laboratories. In this work, the feasibility of monitoring barrel toasting levels using an electronic nose with a metal oxide odor sensor array (MOS) was studied. The results of oak toasting level differentiation obtained via the MOS network were identical to those obtained by analyzing extractable compounds in liquid or gas phase as described in a previous paper. The results presented in this work at the laboratory scale could be used to implement a nondestructive monitoring system based on the analysis of headspace of barrels under industrial conditions.

  16. Early detection of fungal contamination on green coffee by a MOX sensors based Electronic Nose

    Science.gov (United States)

    Sberveglieri, V.; Concina, I.; Falasconi, M.; Gobbi, E.; Pulvirenti, A.; Fava, P.

    2011-09-01

    Fungal growth can occur on green coffee beans along all the distribution chain, eventually bringing on health hazards to consumers, because of the production of toxic metabolites (mycotoxins) [1]. Besides, the sensorial contamination due to volatiles by-products of fungal metabolism could cause defects on coffee also after roasting. Therefore, it is necessary to devise strategies to detect and quantify fungal infection and toxin production at early stages of the food chain. One of the most promising techniques is the analysis of volatile compounds in the headspace gas surrounding the samples. The aim of this work was to verify the ability of the Electronic Nose (EN EOS835) to early detect the microbial contamination of Arabica green coffee. This EN is equipped with Metal Oxide Semiconductor sensor array. Gas chromatography coupled to mass spectrometry (GC-MS) analysis of the static headspace of non-contaminated Arabica green coffee samples was carried out to confirm the EN ability to provide satisfactory indications about the presence of contamination.

  17. Sensor fusion of electron paramagnetic resonance and magnetorelaxometry data for quantitative magnetic nanoparticle imaging

    Science.gov (United States)

    Coene, A.; Leliaert, J.; Crevecoeur, G.; Dupré, L.

    2017-03-01

    Magnetorelaxometry (MRX) imaging and electron paramagnetic resonance (EPR) are two non-invasive techniques capable of recovering the magnetic nanoparticle (MNP) distribution. Both techniques solve an ill-posed inverse problem in order to find the spatial MNP distribution. A lot of research has been done on increasing the stability of these inverse problems with the main objective to improve the quality of MNP imaging. In this paper a proof of concept is presented in which the sensor data of both techniques is fused into EPR-MRX, with the intention to stabilize the inverse problem. First, both techniques are compared by reconstructing several phantoms with different sizes for various noise levels and calculating stability, sensitivity and reconstruction quality parameters for these cases. This study reveals that both techniques are sensitive to different information from the MNP distributions and generate complementary measurement data. As such, their merging might stabilize the inverse problem. In a next step we investigated how both techniques need to be combined to reduce their respective drawbacks, such as a high number of required measurements and reduced stability, and to improve MNP reconstructions. We were able to stabilize both techniques, increase reconstruction quality by an average of 5% and reduce measurement times by 88%. These improvements could make EPR-MRX a valuable and accurate technique in a clinical environment.

  18. Biasing Voltage Dependence of Sensitivity of Electron Beam Evaporated SnO2 Thin Film CO Sensor

    Directory of Open Access Journals (Sweden)

    Sardar M. Ayub Durrani

    2006-09-01

    Full Text Available Thin films of tin oxide were deposited by electron beam evaporation. The effectsof the sensor biasing voltage and film thickness on the CO-sensing of tin oxide thin filmswere investigated. The films were characterized using X-ray diffraction and X-rayphotoelectron spectroscopy All the films were found to be amorphous. The current-voltagecharacteristic of the sensor in air has shown that semiconductor-metal interface formsSchottky barrier. It was found that the CO-sensing properties depend on the sensor biasingvoltage and film thickness. For lower biasing voltages the sensitivity was much higher thanfor the higher voltages. It was found that the sensitivity of the films to CO increased withthe film thickness.

  19. Electrochemical performance and microbial community profiles in microbial fuel cells in relation to electron transfer mechanisms.

    Science.gov (United States)

    Uria, Naroa; Ferrera, Isabel; Mas, Jordi

    2017-10-18

    Microbial fuel cells (MFCs) operating with complex microbial communities have been extensively reported in the past, and are commonly used in applications such as wastewater treatment, bioremediation or in-situ powering of environmental sensors. However, our knowledge on how the composition of the microbial community and the different types of electron transfer to the anode affect the performance of these bioelectrochemical systems is far from complete. To fill this gap of knowledge, we designed a set of three MFCs with different constrains limiting direct and mediated electron transfer to the anode. The results obtained indicate that MFCs with a naked anode on which a biofilm was allowed unrestricted development (MFC-A) had the most diverse archaeal and bacterial community, and offered the best performance. In this MFC both, direct and mediated electron transfer, occurred simultaneously, but direct electron transfer was the predominant mechanism. Microbial fuel cells in which the anode was enclosed in a dialysis membrane and biofilm was not allowed to develop (MFC-D), had a much lower power output (about 60% lower), and a prevalence of dissolved redox species that acted as putative electron shuttles. In the anolyte of this MFC, Arcobacter and Methanosaeta were the prevalent bacteria and archaea respectively. In the third MFC, in which the anode had been covered by a cation selective nafion membrane (MFC-N), power output decreased a further 5% (95% less than MFC-A). In this MFC, conventional organic electron shuttles could not operate and the low power output obtained was presumably attributed to fermentation end-products produced by some of the organisms present in the anolyte, probably Pseudomonas or Methanosaeta. Electron transfer mechanisms have an impact on the development of different microbial communities and in turn on MFC performance. Although a stable current was achieved in all cases, direct electron transfer MFC showed the best performance concluding

  20. Modelling coronal electron density and temperature profiles based on solar magnetic field observations

    Science.gov (United States)

    Rodríguez Gómez, J. M.; Antunes Vieira, L. E.; Dal Lago, A.; Palacios, J.; Balmaceda, L. A.; Stekel, T.

    2017-10-01

    The density and temperature profiles in the solar corona are complex to describe, the observational diagnostics is not easy. Here we present a physics-based model to reconstruct the evolution of the electron density and temperature in the solar corona based on the configuration of the magnetic field imprinted on the solar surface. The structure of the coronal magnetic field is estimated from Potential Field Source Surface (PFSS) based on magnetic field from both observational synoptic charts and a magnetic flux transport model. We use an emission model based on the ionization equilibrium and coronal abundances from CHIANTI atomic database 8.0. The preliminary results are discussed in details.

  1. Positron depth profiling of the structural and electronic structure transformations of hydrogenated Mg-based thin films

    NARCIS (Netherlands)

    Eijt, S.W.H.; Kind, R.; Singh, S.; Schut, H.; Legerstee, W.J.; Hendrikx, R.W.A.; Svetchnikov, V.L.; Westerwaal, R.J.; Dam, B.

    2009-01-01

    We report positron depth-profiling studies on the hydrogen sorption behavior and phase evolution of Mg-based thin films. We show that the main changes in the depth profiles resulting from the hydrogenation to the respective metal hydrides are related to a clear broadening in the observed electron

  2. Thermal and Electronic Transport in Graphene-Based Nanostructures and Applications in Electrical Sensors

    Science.gov (United States)

    Ramnani, Pankaj Ghanshyam

    It is a general consensus that silicon metal-oxide-semiconductor FET (MOSFET) is approaching its scaling limits due to issues including high power dissipation, short channel effects and degraded electrostatics. In recent years, a significant amount of research has been directed towards exploring novel materials like graphene and other two-dimensional atomic crystals to replace Si. Graphene is an ideal candidate owing to its exceptional properties including high carrier mobility (exceeding 15,000 cm2 V -1 s-1), high charge carrier concentration ( 1012 cm -2), low contact resistance due to tunable fermi level, excellent thermal conductivity ( 5000W m-1 K-1), optical transparency ( 97.7%) and flexibility. Despite all these intriguing properties, the absence of a bandgap in graphene has limited its potential applications owing to large off-state currents and low Ion/Ioff ratios observed in graphene-based field effect transistors (FETs). Additionally, most of these experimental studies are conducted using pristine graphene isolated by mechanical exfoliation of graphite, which is not a practical approach for large scale synthesis of graphene. In this dissertation, a scalable method of synthesizing high quality single-layer and bilayer graphene was developed using ambient pressure chemical vapor deposition (AP-CVD). The crystalline nature and physical properties were characterized using electron microscopy and spectroscopic techniques. We investigated the effects of point defects--typically introduced during material characterization and device fabrication steps--on thermal transport in CVD grown single-layer graphene. Furthermore, we investigated methods to engineer a bandgap in graphene by nanopatterning graphene into pseudo one-dimensional nanostructures called graphene nanoribbons (GNRs) using two different top-down approaches. The edge defects in GNRs, which limit carrier mobility and induce p-doping, were characterized using Raman spectroscopy and x

  3. Ultraviolet laser transverse profile shaping for improving x-ray free electron laser performance

    Directory of Open Access Journals (Sweden)

    S. Li

    2017-08-01

    Full Text Available The photocathode rf gun is one of the most critical components in x-ray free electron lasers. The drive laser strikes the photocathode surface, which emits electrons with properties that depend on the shape of the drive laser. Most free electron lasers use photocathodes with work function in the ultraviolet, a wavelength where direct laser manipulation becomes challenging. In this paper, we present a novel application of a digital micromirror device (DMD for the 253 nm drive laser at the Linear Coherent Light Source. Laser profile shaping is accomplished through an iterative algorithm that takes into account shaping error and efficiency. Next, we use laser shaping to control the X-ray laser output via an online optimizer, which shows improvement in FEL pulse energy. Lastly, as a preparation for electron beam shaping, we use the DMD to measure the photocathode quantum efficiency across cathode surface with an averaged laser rms spot size of 59  μm. Our experiments demonstrate promising outlook of using DMD to shape ultraviolet lasers for photocathode rf guns with various applications.

  4. Ultraviolet laser transverse profile shaping for improving x-ray free electron laser performance

    Science.gov (United States)

    Li, S.; Alverson, S.; Bohler, D.; Egger, A.; Fry, A.; Gilevich, S.; Huang, Z.; Miahnahri, A.; Ratner, D.; Robinson, J.; Zhou, F.

    2017-08-01

    The photocathode rf gun is one of the most critical components in x-ray free electron lasers. The drive laser strikes the photocathode surface, which emits electrons with properties that depend on the shape of the drive laser. Most free electron lasers use photocathodes with work function in the ultraviolet, a wavelength where direct laser manipulation becomes challenging. In this paper, we present a novel application of a digital micromirror device (DMD) for the 253 nm drive laser at the Linear Coherent Light Source. Laser profile shaping is accomplished through an iterative algorithm that takes into account shaping error and efficiency. Next, we use laser shaping to control the X-ray laser output via an online optimizer, which shows improvement in FEL pulse energy. Lastly, as a preparation for electron beam shaping, we use the DMD to measure the photocathode quantum efficiency across cathode surface with an averaged laser rms spot size of 59 μ m . Our experiments demonstrate promising outlook of using DMD to shape ultraviolet lasers for photocathode rf guns with various applications.

  5. Micro-calorimetric sensor for vapor phase explosive detection with optimized heat profile

    DEFF Research Database (Denmark)

    Greve, Anders; Olsen, J.; Privorotskaya, N.

    2010-01-01

    A heater design, used in a micro-calorimetric sensor, has been optimized for temperature uniformity in order to increase the sensitivity and reliability of detection of trace amounts of explosives. In this abstract the design, fabrication and characterization is described. The performance of the ...

  6. Energy Bucket: A Tool for Power Profiling and Debugging of Sensor Nodes

    DEFF Research Database (Denmark)

    Andersen, Jacob; Hansen, Morten Tranberg

    2009-01-01

    of current draw. The Energy Bucket provides a light-weight state API for the target system, which facilitates easy scorekeeping of energy consumption between different parts of a target program. We demonstrate how this tool can be used to discover programming errors and debug sensor network applications...

  7. A Novel Optical Morse Code-Based Electronic Lock Using the Ambient Light Sensor and Fuzzy Controller

    OpenAIRE

    Chin-Tan Lee; Tung-Chun Shen; Win-Der Lee

    2017-01-01

    In this work, a novel electronic lock that can encode and decode optical signals, modulated using Morse code conventions, was developed to build a smart home security system based on the Internet of Things (IoT). There are five topics of interest in this research: (1) optical Morse code encoder; (2) optical Morse code decoder; (3) ambient light sensor circuit; (4) fuzzy controller; (5) cloud monitoring system. We take advantage of the light-emitting components as the encoder, which are readil...

  8. Use of a Secondary Current Sensor in Plasma during Electron-Beam Welding with Focus Scanning for Process Control

    OpenAIRE

    Dmitriy Trushnikov; Elena Krotova; Elena Koleva

    2016-01-01

    We consider questions of building a closed-loop focus control system for electron-beam welding. As a feedback signal, we use the secondary current in the plasma that forms above the welding zone. This article presents a model of a secondary current sensor in plasma during electron-beam welding with focus scanning. A comparison of modeled results with experimental data confirms the adequacy of the model. We show that the best results for focus control are obtained when using phase relationship...

  9. Use of an electronic-nose device for profiling headspace volatile metabolites to rapidly identify phytopathogenic microbes [Abstract].

    Science.gov (United States)

    A. Dan Wilson; D.G. Lester

    1997-01-01

    A new electronic-nose device (AromaScan A32S), consisting of an organic matrix-coated polymer-type 32-detector array, was tested as a novel tool for the detection, identification, and discrimination of phytopathogenic microbes. The sensor array detects the unique mixture of volatile metabolites released by microbes growing on standardized growth media by measuring...

  10. Assimilation of FORMOSAT-3/COSMIC electron density profiles into a coupled Thermosphere/Ionosphere model

    Science.gov (United States)

    Lee, I.-Te; Matsuo, Tomoko; Richmond, Arthur D.; Tiger Liu, Jann-Yeng

    2013-04-01

    This paper presents our effort to assimilate FORMOSAT-3/COSMIC (F3/C) GPS Occultation Experiment observations into the National Center for Atmospheric Research (NCAR) Thermosphere Ionosphere Electrodynamics General Circulation Model (TIE-GCM) by means of ensemble Kalman filtering (EnKF). The F3/C EDP are combined with the TIE-GCM simulations by EnKF algorithms implemented in the NCAR Data Assimilation Research Testbed open-source community facility to compute the expected value of electron density, which is 'the best' estimate of the current ionospheric state. Assimilation analyses obtained with real F3/C electron density profiles during geomagnetic quiet time and disturbed period are further compared with independent ground-based observations and global ionospheric map as well as the F3/C profiles themselves. The comparison shows the improvement of the primary ionospheric parameters such as NmF2 and hmF2 and further display some small scale physical meaning structures which might either generally ionospheric features or storm effects. Nevertheless some unrealistic signatures appearing in the results and high rejection rates of observations due to the applied outlier threshold and quality control are also found in the assimilation experiments. These features are additionally analyzed to identify and correct the model biases in the future.

  11. Determination of the sensitivity behavior of an acoustic, thermal flow sensor by electronic characterization

    NARCIS (Netherlands)

    van Honschoten, J.W.; Svetovoy, Vitaly; Lammerink, Theodorus S.J.; Krijnen, Gijsbertus J.M.; Elwenspoek, Michael Curt

    2004-01-01

    The microflown is an acoustic, thermal flow sensor that measures sound particle velocity instead of sound pressure. It is a specific example of a wide range of two- and three-wire thermal flow sensors. For most applications the microflown should be calibrated, which is usually performed acoustically

  12. Determination of the Sensitivity Behaviour of an Acoustic and Thermal Flow Sensor by Electronic Characterisation

    NARCIS (Netherlands)

    van Honschoten, J.W.; Svetovoy, Vitaly; Lammerink, Theodorus S.J.; Krijnen, Gijsbertus J.M.; Elwenspoek, Michael Curt

    2002-01-01

    The Microflown is an acoustic and thermal flow sensor that measures the sound particle velocity instead of sound pressure. For most applications the Microflown should be calibrated, which is usually performed acoustically in a standing-wave-tube. Here it is shown that the sensor's sensitivity and

  13. Electronic Measurement Systems and Procedures for Optical Encoder and Force Sensor Studying

    OpenAIRE

    Dorina Purcaru; Elena Niculescu; Cornelia Gordan

    2009-01-01

    The experimental measurement systems arevery useful in engineering education because the studentscan use and verify their previous knowledge aboutsensors and transducers, signal conditioning and dataprocessing. This paper presents two electronicmeasurement systems which enable the computerizedstudy of the optical encoder and force sensor, respectively.The first sensor studying procedure performs theunderstanding and checking of the rotary incrementalencoder working modes and methods for resol...

  14. Tunable terahertz radiation from arbitrary profile dielectric grating coated with graphene excited by an electron beam

    Science.gov (United States)

    Zhao, Tao; Zhong, Ren-Bin; Hu, Min; Chen, Xiao-Xing; Zhang, Ping; Gong, Sen; Liu, Sheng-Gang

    2015-09-01

    In this paper, the enhanced terahertz radiation transformed from surface plasmon polaritons, excited by a uniformly moving electron bunch, in a structure consisting of a monolayer graphene supported on a dielectric grating with arbitrary profile is investigated. The results show that the grating profile has significant influence on the dispersion curves and radiation characteristics including radiation frequency and intensity. The dependence of dispersion and radiation characteristics on the grating shape for both the symmetric and asymmetric gratings is studied in detail. Moreover, we find that, for an asymmetric grating with certain profile, there exist two different diffraction types, and one of the two types can provide higher radiation intensity comparing to the other one. These results will definitely facilitate the practical application in developing a room-temperature, tunable, coherent and miniature terahertz radiation source. Project supported by the National Basic Research Program of China (Grant No. 2014CB339801), the National Natural Science Foundation of China (Grant Nos. 61231005, 11305030, and 612111076), the Fundamental Research Funds for the Central Universities of China (Grant No. ZYGX2013J058), and the National High-tech Research and Development Project of China (Grant No. 2011AA010204).

  15. Optical and Electronic NO(x) Sensors for Applications in Mechatronics.

    Science.gov (United States)

    Di Franco, Cinzia; Elia, Angela; Spagnolo, Vincenzo; Scamarcio, Gaetano; Lugarà, Pietro Mario; Ieva, Eliana; Cioffi, Nicola; Torsi, Luisa; Bruno, Giovanni; Losurdo, Maria; Garcia, Michael A; Wolter, Scott D; Brown, April; Ricco, Mario

    2009-01-01

    Current production and emerging NO(x) sensors based on optical and nanomaterials technologies are reviewed. In view of their potential applications in mechatronics, we compared the performance of: i) Quantum cascade lasers (QCL) based photoacoustic (PA) systems; ii) gold nanoparticles as catalytically active materials in field-effect transistor (FET) sensors, and iii) functionalized III-V semiconductor based devices. QCL-based PA sensors for NO(x) show a detection limit in the sub part-per-million range and are characterized by high selectivity and compact set-up. Electrochemically synthesized gold-nanoparticle FET sensors are able to monitor NO(x) in a concentration range from 50 to 200 parts per million and are suitable for miniaturization. Porphyrin-functionalized III-V semiconductor materials can be used for the fabrication of a reliable NO(x) sensor platform characterized by high conductivity, corrosion resistance, and strong surface state coupling.

  16. Sensor Networks, Dataloggers, and Other Handy Gadgets Using Open-Source Electronics for the Christina River Basin CZO

    Science.gov (United States)

    Hicks, S. D.; Aufdenkampe, A. K.; Montgomery, D. S.

    2011-12-01

    The search for biogeochemical "hot spots" and "hot moments" that control ecosystem-level processes requires a rethinking of how we observe the environment. Extensive multi-sensor/measurement arrays are required to realize 2D, 3D, or 4D maps of environmental properties with sufficient spatial and temporal resolution to find and understand hot spots and hot moments. To date, the cost of the data logging and communication infrastructure has been a major limitation to large-scale sensor deployment, especially for near-real-time (NRT) wireless networks. A low-cost, user-friendly alternative is needed so that resources can be prioritized toward sensor hardware rather than data acquisition and communication hardware. A flexible development platform would also allow for easy creation of other useful devices in addition to the already apparent need for economical dataloggers. The recent proliferation of open-source electronics platforms offers an opportunity for environmental observatories to deploy sensors at large scales by reducing data logging and communications costs by more than an order of magnitude. Leading the open-source electronics revolution is the Arduino project, designed to make the process of using electronics in multidisciplinary projects more accessible to hobbyists and professionals alike. A large user community has developed and shared hundreds of practical applications for projects that interface with a variety of sensors and use embedded logic to control external hardware. Likewise, dozens of companies and individuals sell low-cost Arduino-compatible boards that can connect together in a modular framework, allowing the user to quickly create devices for a wide range of applications. Based on these open-source technologies and products, we are designing and building a variety of circuit devices for use in our research watersheds. One Arduino-based device is a multi-channel datalogger that can be used with a variety of analog and digital sensors, such as

  17. Radial Profiles of Plasma Electron Characteristics in a Low-Power Arcjet

    Science.gov (United States)

    Codron, Douglas; Nawaz, Anuscheh

    2013-01-01

    Since 1960, the Arc Jet Complex at NASA Ames Research Center has been a source of long-duration, high-enthalpy flow for materials testing with application to the thermal protection of aerospace vehicle components. From their inception the facilities have played an integral role supporting many of NASA's space flight programs and numerous DoD projects. In recent years advancements in computational fluid dynamics (CFO) have made the resultant models a valuable tool for assessing and predicting performance, however, the inherent limitation of models to compensate for a dissociated, transitionally high temperature nonequilibrated flowfield have made further measurements necessary. The use of electrostatic probe diagnostics within similarly harsh plasma environments in previous studies have been met with much success. In this study, the use of a single Langmuir probe was implemented to characterize the plasma parameters of interest as they vary radially within a large volume of the plume. Classical Langmuir probe theory was applied to achieve first order estimates of the heavy particle temperature, the ratio T(sub i)/T(sub e), and the ionization fraction. As expected, both the electron temperature and electron density measurements show a dependence on radial distance from the plume centerline, with electron density profiles showing the largest dependence. This paper aims to validate and strengthen modeling work conducted at the NASA Ames Research Center by measuring the critical plasma parameters (electron temperature, electron density, and plasma potential) within the arc plume of a subscale arc jet. These parameters are intended to give physical insight into the flow characteristics while providing the necessary boundary conditions to validate full scale simulations.

  18. Tailored electron bunches with smooth current profiles for enhanced transformer ratios in beam-driven acceleration

    Directory of Open Access Journals (Sweden)

    F. Lemery

    2015-08-01

    Full Text Available Collinear high-gradient O(GV/m beam-driven wakefield methods for charged-particle acceleration could be critical to the realization of compact, cost-efficient, accelerators, e.g., in support of TeV-scale lepton colliders or multiple-user free-electron laser facilities. To make these options viable, the high accelerating fields need to be complemented with large transformer ratios >2, a parameter characterizing the efficiency of the energy transfer between a wakefield-exciting “drive” bunch to an accelerated “witness” bunch. While several potential current distributions have been discussed, their practical realization appears challenging due to their often discontinuous nature. In this paper we propose several alternative continuously differentiable (smooth current profiles which support enhanced transformer ratios. We especially demonstrate that one of the devised shapes can be implemented in a photo-emission electron source by properly shaping the photocathode-laser pulse. We finally discuss a possible superconducting linear-accelerator concept that could produce shaped drive bunches at high-repetition rates to drive a dielectric-wakefield accelerator with accelerating fields on the order of ∼60  MV/m and a transformer ratio ∼5 consistent with a recently proposed multiuser free-electron laser facility.

  19. Longitudinal profile diagnostic scheme with subfemtosecond resolution for high-brightness electron beams

    Directory of Open Access Journals (Sweden)

    G. Andonian

    2011-07-01

    Full Text Available High-resolution measurement of the longitudinal profile of a relativistic electron beam is of utmost importance for linac based free-electron lasers and other advanced accelerator facilities that employ ultrashort bunches. In this paper, we investigate a novel scheme to measure ultrashort bunches (subpicosecond with exceptional temporal resolution (hundreds of attoseconds and dynamic range. The scheme employs two orthogonally oriented deflecting sections. The first imparts a short-wavelength (fast temporal resolution horizontal angular modulation on the beam, while the second imparts a long-wavelength (slow angular kick in the vertical dimension. Both modulations are observable on a standard downstream screen in the form of a streaked sinusoidal beam structure. We demonstrate, using scaled variables in a quasi-1D approximation, an expression for the temporal resolution of the scheme and apply it to a proof-of-concept experiment at the UCLA Neptune high-brightness injector facility. The scheme is also investigated for application at the SLAC NLCTA facility, where we show that the subfemtosecond resolution is sufficient to resolve the temporal structure of the beam used in the echo-enabled free-electron laser. We employ beam simulations to verify the effect for typical Neptune and NLCTA parameter sets and demonstrate the feasibility of the concept.

  20. Retrieval of Electron Density Profile for KOMPSAT-5 GPS Radio Occultation

    Directory of Open Access Journals (Sweden)

    Woo-Kyoung Lee

    2007-12-01

    Full Text Available The AOPOD (Atmosphere Occultation and Precision Orbit Determination system, the secondary payload of KOMPSAT (KOrea Multi-Purpose SATellite-5 scheduled to be launched in 2010, shall provide GPS radio occultation data. In this paper, we simulated the GPS radio occultation characteristic of KOMPSAT-5 and retrieved electron density profiles using KROPS (KASI Radio Occultation Processing Software. The electron density retrieved from CHAMP (CHAllenging Minisatellite Payload GPS radio occultation data on June 20, 2004 was compared with IRI (International Reference Ionosphere - 2001, PLP (Planar Langmuir Probe, and ionosonde measurements. When the result was compared with ionosonde measurements, the discrepancies were 5 km on the F_2 peak height (hmF_2 and 3×10^{10} el/m^3 on the electron density of the F_2 peak height (NmF_2. By comparing with the Langmuir Probe measurements of CHAMP satellite (PLP, both agrees with 1.6×10^{11} el/m^3 at the height of 365.6 km.

  1. Discrimination method of the volatiles from fresh mushrooms by an electronic nose using a trapping system and statistical standardization to reduce sensor value variation

    National Research Council Canada - National Science Library

    Fujioka, Kouki; Shimizu, Nobuo; Manome, Yoshinobu; Ikeda, Keiichi; Yamamoto, Kenji; Tomizawa, Yasuko

    2013-01-01

    ..., cosmetics, medicine, and agriculture. However, measurement values from electronic noses have a tendency to vary under humidity or alcohol exposure conditions, since several types of sensors in the devices are affected by such variables...

  2. Calibration of a Sensor Array (an Electronic Tongue for Identification and Quantification of Odorants from Livestock Buildings

    Directory of Open Access Journals (Sweden)

    Jens Jørgen Lønsmann Iversen

    2007-01-01

    Full Text Available This contribution serves a dual purpose. The first purpose was to investigate the possibility of using a sensor array (an electronic tongue for on-line identification and quantification of key odorants representing a variety of chemical groups at two different acidities, pH 6 and 8. The second purpose was to simplify the electronic tongue by decreasing the number of electrodes from 14, which was the number of electrodes in the prototype. Different electrodes were used for identification and quantification of different key odorants. A total of eight electrodes were sufficient for identification and quantification in micromolar concentrations of the key odorants n-butyrate, ammonium and phenolate in test mixtures also containing iso-valerate, skatole and p-cresolate. The limited number of electrodes decreased the standard deviation and the relative standard deviation of triplicate measurements in comparison with the array comprising 14 electrodes. The electronic tongue was calibrated using 4 different test mixtures, each comprising 50 different combinations of key odorants in triplicates, a total of 600 measurements. Back propagation artificial neural network, partial least square and principal component analysis were used in the data analysis. The results indicate that the electronic tongue has a promising potential as an on- line sensor for odorants absorbed in the bioscrubber used in livestock buildings.

  3. Calibration of a Sensor Array (an Electronic Tongue) for Identification and Quantification of Odorants from Livestock Buildings

    Science.gov (United States)

    Abu-Khalaf, Nawaf; Iversen, Jens Jørgen Lønsmann

    2007-01-01

    This contribution serves a dual purpose. The first purpose was to investigate the possibility of using a sensor array (an electronic tongue) for on-line identification and quantification of key odorants representing a variety of chemical groups at two different acidities, pH 6 and 8. The second purpose was to simplify the electronic tongue by decreasing the number of electrodes from 14, which was the number of electrodes in the prototype. Different electrodes were used for identification and quantification of different key odorants. A total of eight electrodes were sufficient for identification and quantification in micromolar concentrations of the key odorants n-butyrate, ammonium and phenolate in test mixtures also containing iso-valerate, skatole and p-cresolate. The limited number of electrodes decreased the standard deviation and the relative standard deviation of triplicate measurements in comparison with the array comprising 14 electrodes. The electronic tongue was calibrated using 4 different test mixtures, each comprising 50 different combinations of key odorants in triplicates, a total of 600 measurements. Back propagation artificial neural network, partial least square and principal component analysis were used in the data analysis. The results indicate that the electronic tongue has a promising potential as an online sensor for odorants absorbed in the bioscrubber used in livestock buildings.

  4. Electronic Energy Meter Based on a Tunnel Magnetoresistive Effect (TMR) Current Sensor

    National Research Council Canada - National Science Library

    Enrique García Vidal; Diego Ramírez Muñoz; Sergio Ivan Ravelo Arias; Jaime Sanchez Moreno; Susana Cardoso; Ricardo Ferreira; Paulo Freitas

    2017-01-01

    ...) electrical current sensor is presented. After its physical and electrical characterization, a wattmeter is developed to determine the active power delivered to a load from the AC 50/60 Hz mains line...

  5. Integration of a High Sensitivity MEMS Directional Sound Sensor With Readout Electronics

    Science.gov (United States)

    2012-12-01

    Verification by Laser Vibrometer At times the MS3110 was properly working but the sensor was not. Verification of sensor operation was done with a... laser vibrometer . To test this, the device was excited at the bending-mode resonant frequency and the displacement was measured. Although this test...computer as the MS3110 software. Specifically, the laser - vibrometer software seemed to trigger a reset of the volatile registers. b. Proper Connections

  6. Diffuse scattering provides material parameters and electron density profiles of biomembranes.

    Science.gov (United States)

    Liu, Yufeng; Nagle, John F

    2004-04-01

    Fully hydrated stacks of DOPC lipid bilayer membranes generate large diffuse x-ray scattering that corrupts the Bragg peak intensities that are used in conventional biophysical structural analysis, but the diffuse scattering actually contains more information. Using an efficient algorithm for fitting extensive regions of diffuse data to classical smectic liquid crystalline theory we first obtain the compressional modulus B= 10(13) erg/ cm(4), which involves interactions between membranes, and the bending modulus K(c) =8x 10(-13) erg of the membranes. The membrane form factor F ( q(z) ) is then obtained for most values of q(z) up to 0.8 A(-1). The electron density profile rho(z) is obtained by fitting models to F( q(z) ). Constraining the models to conform to other measurements provides structural quantities such as area A=72.1+/-0.5 A(2) per lipid at the interface.

  7. Commissioning and First Results of the Electron Beam Profiler in the Main Injector at Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    Thurman-Keup, R. [Fermilab; Alvarez, M. [Fermilab; Fitzgerald, J. [Fermilab; Lundberg, C. [Fermilab; Prieto, P. [Fermilab; Zagel, J. [Fermilab; Blokland, W. [Oak Ridge

    2017-08-01

    The planned neutrino program at Fermilab requires large proton beam intensities in excess of 2 MW. Measuring the transverse profiles of these high intensity beams is challenging and often depends on non-invasive techniques. One such technique involves measuring the deflection of a probe beam of electrons with a trajectory perpendicular to the proton beam. A device such as this is already in use at the Spallation Neutron Source at ORNL and a similar device has been installed in the Main Injector at Fermilab. Commissioning of the device is in progress with the goal of having it operational by the end of the year. The status of the commissioning and initial results will be presented

  8. Measurements of the Suprathermal Electron Density Profile by Electron Cyclotron Emission at the Upper Cut-Off Layer in Tore Supra

    NARCIS (Netherlands)

    Schokker, B. C.; Talvard, M.; Cardozo, N. J. L.; Giruzzi, G.

    1995-01-01

    The possibility of measuring the radial profile of fast-electron distributions from ECE spectra is discussed. The most usual ECE diagnostic set-up, i.e. the second-harmonic X-mode, observed by low-held side antennae in the equatorial plane, can be used by exploiting the reflection of spontaneously

  9. Engineering highly organized and aligned single walled carbon nanotube networks for electronic device applications: Interconnects, chemical sensor, and optoelectronics

    Science.gov (United States)

    Kim, Young Lae

    For 20 years, single walled carbon nanotubes (SWNTs) have been studied actively due to their unique one-dimensional nanostructure and superior electrical, thermal, and mechanical properties. For these reasons, they offer the potential to serve as building blocks for future electronic devices such as field effect transistors (FETs), electromechanical devices, and various sensors. In order to realize these applications, it is crucial to develop a simple, scalable, and reliable nanomanufacturing process that controllably places aligned SWNTs in desired locations, orientations, and dimensions. Also electronic properties (semiconducting/metallic) of SWNTs and their organized networks must be controlled for the desired performance of devices and systems. These fundamental challenges are significantly limiting the use of SWNTs for future electronic device applications. Here, we demonstrate a strategy to fabricate highly controlled micro/nanoscale SWNT network structures and present the related assembly mechanism to engineer the SWNT network topology and its electrical transport properties. A method designed to evaluate the electrical reliability of such nano- and microscale SWNT networks is also presented. Moreover, we develop and investigate a robust SWNT based multifunctional selective chemical sensor and a range of multifunctional optoelectronic switches, photo-transistors, optoelectronic logic gates and complex optoelectronic digital circuits.

  10. A Novel Optical Morse Code-Based Electronic Lock Using the Ambient Light Sensor and Fuzzy Controller

    Directory of Open Access Journals (Sweden)

    Chin-Tan Lee

    2017-02-01

    Full Text Available In this work, a novel electronic lock that can encode and decode optical signals, modulated using Morse code conventions, was developed to build a smart home security system based on the Internet of Things (IoT. There are five topics of interest in this research: (1 optical Morse code encoder; (2 optical Morse code decoder; (3 ambient light sensor circuit; (4 fuzzy controller; (5 cloud monitoring system. We take advantage of the light-emitting components as the encoder, which are readily available in hand-held mobile devices (e.g., Smart phones and photoresistors and a microcontroller as the decoder. By Wi-Fi transferring, even without a personal computer, real-time information about this lock can be uploaded to the cloud service platform, and helps users to ensure home safety on the remote monitoring system. By using the ambient light sensor and fuzzy controller in this novel optical Morse code-based electronic lock, experimental results show that the reliability of this system is much improved from 65% to 100%. That means that it is highly resistant to different illumination conditions in the work environment, and therefore all functions, including coding, emitting, receiving, decoding, uploading and cloud monitoring, can work well. Furthermore, besides the convenience and cost reduction, by incorporating traditional keys into smart phones, as a consumer electronics, our proposed system is suitable for users of all ages because of a user-friendly operation interface.

  11. Ultrasonic and LIDAR sensors for electronic canopy characterization in vineyards: advances to improve pesticide application methods.

    Science.gov (United States)

    Llorens, Jordi; Gil, Emilio; Llop, Jordi; Escolà, Alexandre

    2011-01-01

    Canopy characterization is a key factor to improve pesticide application methods in tree crops and vineyards. Development of quick, easy and efficient methods to determine the fundamental parameters used to characterize canopy structure is thus an important need. In this research the use of ultrasonic and LIDAR sensors have been compared with the traditional manual and destructive canopy measurement procedure. For both methods the values of key parameters such as crop height, crop width, crop volume or leaf area have been compared. Obtained results indicate that an ultrasonic sensor is an appropriate tool to determine the average canopy characteristics, while a LIDAR sensor provides more accuracy and detailed information about the canopy. Good correlations have been obtained between crop volume (C(VU)) values measured with ultrasonic sensors and leaf area index, LAI (R(2) = 0.51). A good correlation has also been obtained between the canopy volume measured with ultrasonic and LIDAR sensors (R(2) = 0.52). Laser measurements of crop height (C(HL)) allow one to accurately predict the canopy volume. The proposed new technologies seems very appropriate as complementary tools to improve the efficiency of pesticide applications, although further improvements are still needed.

  12. B36 borophene as an electronic sensor for formaldehyde: Quantum chemical analysis

    Science.gov (United States)

    Shahbazi Kootenaei, Amirhossein; Ansari, Goodarz

    2016-08-01

    Pristine carbon nanotubes and graphene show great sensitivity toward several lethal gases but cannot identify some extremely toxic chemicals such as formaldehyde (HCOH). Recent successful synthesis of all-boron graphene-like sheets attracted strong interest in exploring their possible applications. Herein, we inspected the potential application of B36 borophene sheet as a sensor for HCOH detection, using density functional theory computations. Different theoretical levels including B97D and Minnesota 06 functionals with different basis sets were employed. It was predicted that the electrical conductivity of B36 borophene significantly increases at the presence of HCOH molecules, thereby generating an electrical signal. The electrical signal is increased by increasing the number of adsorbed HCOH molecules, indicating that this sensor is sensitive to the concentration (or pressure) of HCOH gas. These results suggest that the pristine borophene may be used in the HCOH chemical sensors.

  13. Toward a Micro-Scale Acoustic Direction-Finding Sensor with Integrated Electronic Readout

    Science.gov (United States)

    2013-06-01

    The sensor used in the nanoindenter study could not be removed intact from the mount for laser vibrometer testing. Because there is variation in...measured using a laser vibrometer . Rocking frequency (kHz) Bending frequency (kHz) Analytical model 1.79 2.83 FEM 1.53 2.91 Estimated from stiffness 1.71...vibration response spectra of the two sensors, shown in Fig. 3.3, were measured using a Polytec laser vibrometer aimed at one wingtip. 2.2 2.4 2.6 2.8 3 0 1

  14. B{sub 36} borophene as an electronic sensor for formaldehyde: Quantum chemical analysis

    Energy Technology Data Exchange (ETDEWEB)

    Shahbazi Kootenaei, Amirhossein, E-mail: a.kootenaei@gmail.com [Department of Chemical Engineering, Mahshahr Branch, Islamic Azad University, Mahshahr (Iran, Islamic Republic of); Ansari, Goodarz [Department of Chemistry, Mahshahr Branch, Islamic Azad University, Mahshahr (Iran, Islamic Republic of)

    2016-08-06

    Pristine carbon nanotubes and graphene show great sensitivity toward several lethal gases but cannot identify some extremely toxic chemicals such as formaldehyde (HCOH). Recent successful synthesis of all-boron graphene-like sheets attracted strong interest in exploring their possible applications. Herein, we inspected the potential application of B{sub 36} borophene sheet as a sensor for HCOH detection, using density functional theory computations. Different theoretical levels including B97D and Minnesota 06 functionals with different basis sets were employed. It was predicted that the electrical conductivity of B{sub 36} borophene significantly increases at the presence of HCOH molecules, thereby generating an electrical signal. The electrical signal is increased by increasing the number of adsorbed HCOH molecules, indicating that this sensor is sensitive to the concentration (or pressure) of HCOH gas. These results suggest that the pristine borophene may be used in the HCOH chemical sensors. - Highlights: • B{sub 36} borophene sheet can be used as a chemical sensor for HCOH detection. • The B{sub 36} is sensitive to the concentration of HCOH. • When the B{sub 36} adsorbs HCOH molecules, it is converted to a p-type semiconductor.

  15. Organic Optical Sensor Based on Monolithic Integration of Organic Electronic Devices

    Directory of Open Access Journals (Sweden)

    Hoi Lam Tam

    2015-09-01

    Full Text Available A novel organic optical sensor that integrates a front organic light-emitting diode (OLED and an organic photodiode (OPD is demonstrated. The stripe-shaped cathode is used in the OLED components to create light signals, while the space between the stripe-shaped cathodes serves as the detection window for integrated OPD units. A MoO3 (5 nm/Ag (15 nm bi-layer inter-electrode is interposed between the vertically stacked OLED and OPD units, serving simultaneously as the cathode for the front OLED and an anode for the upper OPD units in the sensor. In the integrated sensor, the emission of the OLED units is confined by the area of the opaque stripe-shaped cathodes, optimized to maximize the reflected light passing through the window space for detection by the OPD components. This can ensure high OLED emission output, increasing the signal/noise ratio. The design and fabrication flexibility of an integrated OLED/OPD device also has low cost benefits, and is light weight and ultra-thin, making it possible for application in wearable units, finger print identification, image sensors, smart light sources, and compact information systems.

  16. Development, fabrication, and modeling of highly sensitive conjugated polymer based piezoresistive sensors in electronic skin applications

    Science.gov (United States)

    Khalili, Nazanin; Naguib, Hani E.; Kwon, Roy H.

    2016-04-01

    Human intervention can be replaced through development of tools resulted from utilizing sensing devices possessing a wide range of applications including humanoid robots or remote and minimally invasive surgeries. Similar to the five human senses, sensors interface with their surroundings to stimulate a suitable response or action. The sense of touch which arises in human skin is among the most challenging senses to emulate due to its ultra high sensitivity. This has brought forth novel challenging issues to consider in the field of biomimetic robotics. In this work, using a multiphase reaction, a polypyrrole (PPy) based hydrogel is developed as a resistive type pressure sensor with an intrinsically elastic microstructure stemming from three dimensional hollow spheres. Furthermore, a semi-analytical constriction resistance model accounting for the real contact area between the PPy hydrogel sensors and the electrode along with the dependency of the contact resistance change on the applied load is developed. The model is then solved using a Monte Carlo technique and the sensitivity of the sensor is obtained. The experimental results showed the good tracking ability of the proposed model.

  17. A Comparative Study of Physiological Monitoring with a Wearable Opto-Electronic Patch Sensor (OEPS for Motion Reduction

    Directory of Open Access Journals (Sweden)

    Abdullah Alzahrani

    2015-06-01

    Full Text Available This paper presents a comparative study in physiological monitoring between a wearable opto-electronic patch sensor (OEPS comprising a three-axis Microelectromechanical systems (MEMs accelerometer (3MA and commercial devices. The study aims to effectively capture critical physiological parameters, for instance, oxygen saturation, heart rate, respiration rate and heart rate variability, as extracted from the pulsatile waveforms captured by OEPS against motion artefacts when using the commercial probe. The protocol involved 16 healthy subjects and was designed to test the features of OEPS, with emphasis on the effective reduction of motion artefacts through the utilization of a 3MA as a movement reference. The results show significant agreement between the heart rates from the reference measurements and the recovered signals. Significance of standard deviation and error of mean yield values of 2.27 and 0.65 beats per minute, respectively; and a high correlation (0.97 between the results of the commercial sensor and OEPS. T, Wilcoxon and Bland-Altman with 95% limit of agreement tests were also applied in the comparison of heart rates extracted from these sensors, yielding a mean difference (MD: 0.08. The outcome of the present work incites the prospects of OEPS on physiological monitoring during physical activities.

  18. Use of a Secondary Current Sensor in Plasma during Electron-Beam Welding with Focus Scanning for Process Control

    Directory of Open Access Journals (Sweden)

    Dmitriy Trushnikov

    2016-01-01

    Full Text Available We consider questions of building a closed-loop focus control system for electron-beam welding. As a feedback signal, we use the secondary current in the plasma that forms above the welding zone. This article presents a model of a secondary current sensor in plasma during electron-beam welding with focus scanning. A comparison of modeled results with experimental data confirms the adequacy of the model. We show that the best results for focus control are obtained when using phase relationships rather than amplitude relationships. We outline the principles for building an EBW focus control system based on parameters of the secondary current in plasma. We simulate the work of a control system’s circuits and demonstrate the stability of the synthesized system. We have conducted pilot tests on an experimental prototype.

  19. Charge and current density profiles of a degenerate magnetized free-electron gas near a hard wall

    NARCIS (Netherlands)

    Kettenis, M.M.; Suttorp, L.G.

    1998-01-01

    The charge and current densities of a completely degenerate free-electron gas in a uniform magnetic field are found to have a damped oscillatory spatial dependence near a wall that is parallel to the magnetic field. For large distances from the wall the behaviour of the associated profile functions

  20. Magnon, phonon, and electron temperature profiles and the spin Seebeck effect in magnetic insulator/normal metal hybrid structures

    NARCIS (Netherlands)

    Schreier, M.; Kamra, A.; Weiler, M.; Xiao, J.; Bauer, G.E.W.; Gross, R.; Goennenwein, S.T.B.

    2013-01-01

    We calculate the phonon, electron, and magnon temperature profiles in yttrium iron garnet/platinum bilayers by diffusive theory with appropriate boundary conditions, in particular taking into account interfacial thermal resistances. Our calculations show that in thin film hybrids, the interface

  1. Packaging Technologies for 500 C SiC Electronics and Sensors: Challenges in Material Science and Technology

    Science.gov (United States)

    Chen, Liang-Yu; Neudeck, Philip G.; Behelm, Glenn M.; Spry, David J.; Meredith, Roger D.; Hunter, Gary W.

    2015-01-01

    This paper presents ceramic substrates and thick-film metallization based packaging technologies in development for 500C silicon carbide (SiC) electronics and sensors. Prototype high temperature ceramic chip-level packages and printed circuit boards (PCBs) based on ceramic substrates of aluminum oxide (Al2O3) and aluminum nitride (AlN) have been designed and fabricated. These ceramic substrate-based chip-level packages with gold (Au) thick-film metallization have been electrically characterized at temperatures up to 550C. The 96 alumina packaging system composed of chip-level packages and PCBs has been successfully tested with high temperature SiC discrete transistor devices at 500C for over 10,000 hours. In addition to tests in a laboratory environment, a SiC junction field-effect-transistor (JFET) with a packaging system composed of a 96 alumina chip-level package and an alumina printed circuit board was tested on low earth orbit for eighteen months via a NASA International Space Station experiment. In addition to packaging systems for electronics, a spark-plug type sensor package based on this high temperature interconnection system for high temperature SiC capacitive pressure sensors was also developed and tested. In order to further significantly improve the performance of packaging system for higher packaging density, higher operation frequency, power rating, and even higher temperatures, some fundamental material challenges must be addressed. This presentation will discuss previous development and some of the challenges in material science (technology) to improve high temperature dielectrics for packaging applications.

  2. Performance optimization of apodized FBG-based temperature sensors in single and quasi-distributed DWDM systems with new and different apodization profiles

    Energy Technology Data Exchange (ETDEWEB)

    Mohammed, Nazmi A. [Research Center, Smart Village, College of Engineering, Arab Academy for Science, Technology, and Maritime Transport, Cairo (Egypt); Ali, Taha A., E-mail: Taha25@gmail.com; Aly, Moustafa H. [Department of Electronics and Communications Engineering, College of Engineering, Arab Academy for Science, Technology, and Maritime Transport, Cairo (Egypt)

    2013-12-15

    In this work, different FBG temperature sensors are designed and evaluated with various apodization profiles. Evaluation is done under a wide range of controlling design parameters like sensor length and refractive index modulation amplitude, targeting a remarkable temperature sensing performance. New judgment techniques are introduced such as apodization window roll-off rate, asymptotic sidelobe (SL) decay level, number of SLs, and average SL level (SLav). Evaluation techniques like reflectivity, Full width at Half Maximum (FWHM), and Sidelobe Suppression Ratio (SLSR) are also used. A “New” apodization function is proposed, which achieves better performance like asymptotic decay of 18.4 dB/nm, high SLSR of 60 dB, high channel isolation of 57.9 dB, and narrow FWHM less than 0.15 nm. For a single accurate temperature sensor measurement in extensive noisy environment, optimum results are obtained by the Nuttall apodization profile and the new apodization function, which have remarkable SLSR. For a quasi-distributed FBG temperature sensor the Barthann and the new apodization profiles obtain optimum results. Barthann achieves a high asymptotic decay of 40 dB/nm, a narrow FWHM (less than 25 GHZ), a very low SLav of −45.3 dB, high isolation of 44.6 dB, and a high SLSR of 35 dB. The new apodization function achieves narrow FWHM of 0.177 nm, very low SL of −60.1, very low SLav of −63.6 dB, and very high SLSR of −57.7 dB. A study is performed on including an unapodized sensor among apodized sensors in a quasi-distributed sensing system. Finally, an isolation examination is performed on all the discussed apodizations and a linear relation between temperature and the Bragg wavelength shift is observed experimentally and matched with the simulated results.

  3. Performance optimization of apodized FBG-based temperature sensors in single and quasi-distributed DWDM systems with new and different apodization profiles

    Directory of Open Access Journals (Sweden)

    Nazmi A. Mohammed

    2013-12-01

    Full Text Available In this work, different FBG temperature sensors are designed and evaluated with various apodization profiles. Evaluation is done under a wide range of controlling design parameters like sensor length and refractive index modulation amplitude, targeting a remarkable temperature sensing performance. New judgment techniques are introduced such as apodization window roll-off rate, asymptotic sidelobe (SL decay level, number of SLs, and average SL level (SLav. Evaluation techniques like reflectivity, Full width at Half Maximum (FWHM, and Sidelobe Suppression Ratio (SLSR are also used. A “New” apodization function is proposed, which achieves better performance like asymptotic decay of 18.4 dB/nm, high SLSR of 60 dB, high channel isolation of 57.9 dB, and narrow FWHM less than 0.15 nm. For a single accurate temperature sensor measurement in extensive noisy environment, optimum results are obtained by the Nuttall apodization profile and the new apodization function, which have remarkable SLSR. For a quasi-distributed FBG temperature sensor the Barthann and the new apodization profiles obtain optimum results. Barthann achieves a high asymptotic decay of 40 dB/nm, a narrow FWHM (less than 25 GHZ, a very low SLav of −45.3 dB, high isolation of 44.6 dB, and a high SLSR of 35 dB. The new apodization function achieves narrow FWHM of 0.177 nm, very low SL of −60.1, very low SLav of −63.6 dB, and very high SLSR of −57.7 dB. A study is performed on including an unapodized sensor among apodized sensors in a quasi-distributed sensing system. Finally, an isolation examination is performed on all the discussed apodizations and a linear relation between temperature and the Bragg wavelength shift is observed experimentally and matched with the simulated results.

  4. Electronic simulation of a barometric pressure sensor for the meteorological monitor assembly

    Science.gov (United States)

    Guiar, C. N.; Duff, L. W.

    1982-01-01

    An analysis of the electronic simulation of barometric pressure used to self-test the counter electronics of the digital barometer is presented. The barometer is part of the Meteorological Monitor Assembly that supports navigation in deep space communication. The theory of operation of the digital barometer, the design details, and the verification procedure used with the barometric pressure simulator are presented.

  5. Final Technical Report - 300°C Capable Electronics Platform and Temperature Sensor System For Enhanced Geothermal Systems

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Cheng-Po; Shaddock, David; Sandvik, Peter; Saia, Rich; Amita Patil, Alexey Vert; Zhang, Tan

    2012-11-30

    A silicon carbide (SiC) based electronic temperature sensor prototype has been demonstrated to operate at 300°C. We showed continuous operation of 1,000 hours with SiC operational amplifier and surface mounted discreet resistors and capacitors on a ceramic circuit board. This feasibility demonstration is a major milestone in the development of high temperature electronics in general and high temperature geothermal exploration and well management tools in particular. SiC technology offers technical advantages that are not found in competing technologies such as silicon-on-insulator (SOI) at high temperatures of 200°C to 300°C and beyond. The SiC integrated circuits and packaging methods can be used in new product introduction by GE Oil and Gas for high temperature down-hole tools. The existing SiC fabrication facility at GE is sufficient to support the quantities currently demanded by the marketplace, and there are other entities in the United States and other countries capable of ramping up SiC technology manufacturing. The ceramic circuit boards are different from traditional organic-based electronics circuit boards, but the fabrication process is compatible with existing ceramic substrate manufacturing. This project has brought high temperature electronics forward, and brings us closer to commercializing tools that will enable and reduce the cost of enhanced geothermal technology to benefit the public in terms of providing clean renewable energy at lower costs.

  6. MOS-FET as a Current Sensor in Power Electronics Converters

    OpenAIRE

    Rok Pajer; Miro Milanoviĉ; Branko Premzel; Miran Rodiĉ

    2015-01-01

    This paper presents a current sensing principle appropriate for use in power electronics’ converters. This current measurement principle has been developed for metal oxide semiconductor field effect transistor (MOS-FET) and is based on U D S voltage measurement. In practice, shunt resistors and Hall effect sensors are usually used for these purposes, but the presented principle has many advantages. There is no need for additional circuit elements within high current paths, causing parasitic i...

  7. Profile and Morphology of Fungal Aerosols Characterized by Field Emission Scanning Electron Microscopy (FESEM).

    Science.gov (United States)

    Afanou, Komlavi Anani; Straumfors, Anne; Skogstad, Asbjørn; Skaar, Ida; Hjeljord, Linda; Skare, Øivind; Green, Brett James; Tronsmo, Arne; Eduard, Wijnand

    Fungal aerosols consist of spores and fragments with diverse array of morphologies; however, the size, shape, and origin of the constituents require further characterization. In this study, we characterize the profile of aerosols generated from Aspergillus fumigatus, A. versicolor, and Penicillium chrysogenum grown for 8 weeks on gypsum boards. Fungal particles were aerosolized at 12 and 20 L min-1 using the Fungal Spore Source Strength Tester (FSSST) and the Stami particle generator (SPG). Collected particles were analyzed with field emission scanning electron microscopy (FESEM). We observed spore particle fraction consisting of single spores and spore aggregates in four size categories, and a fragment fraction that contained submicronic fragments and three size categories of larger fragments. Single spores dominated the aerosols from A. fumigatus (median: 53%), while the submicronic fragment fraction was the highest in the aerosols collected from A. versicolor (median: 34%) and P. chrysogenum (median: 31%). Morphological characteristics showed near spherical particles that were only single spores, oblong particles that comprise some spore aggregates and fragments (3.5 μm). Further, the near spherical particles dominated the aerosols from A. fumigatus (median: 53%), while oblong particles were dominant in the aerosols from A. versicolor (68%) and P. chrysogenum (55%). Fiber-like particles represented 21% and 24% of the aerosols from A. versicolor and P. chrysogenum, respectively. This study shows that fungal particles of various size, shape, and origin are aerosolized, and supports the need to include a broader range of particle types in fungal exposure assessment.

  8. Study of electronic structure and Compton profiles of transition metal diborides

    Science.gov (United States)

    Bhatt, Samir; Heda, N. L.; Kumar, Kishor; Ahuja, B. L.

    2017-08-01

    We report Compton profiles (CPs) of transition metal diborides (MB2; M= Ti and Zr) using a 740 GBq 137Cs Compton spectrometer measured at an intermediate resolution of 0.34 a.u. To validate the experimental momentum densities, we have employed the linear combination of atomic orbitals (LCAO) method to compute the theoretical CPs along with the energy bands, density of states (DOS) and Mulliken's population response. The LCAO computations have been performed in the frame work of density functional theory (DFT) and hybridization of Hartree-Fock and DFT (namely B3LYP and PBE0). For both the diborides, the CPs based on revised Perdew-Burke-Ernzerhof exchange and correlation functions (DFT-PBESol) lead to a better agreement with the experimental momentum densities than other reported approximations. Energy bands, DOS and real space analysis of CPs confirm a metallic-like character of both the borides. Further, a comparison of DFT-PBESol and experimental data on equal-valence-electron-density scale shows more ionicity in ZrB2 than that in TiB2, which is also supported by the Mulliken's population based charge transfer data.

  9. High-throughput functional microRNAs profiling by recombinant AAV-based microRNA sensor arrays.

    Directory of Open Access Journals (Sweden)

    Wenhong Tian

    Full Text Available BACKGROUND: microRNAs (miRNAs are small and non-coding RNAs which play critical roles in physiological and pathological processes. A number of methods have been established to detect and quantify miRNA expression. However, method for high-throughput miRNA function detection is still lacking. PRINCIPAL FINDINGS: We describe an adeno-associated virus (AAV vector-based microRNA (miRNA sensor (Asensor array for high-throughput functional miRNA profiling. Each Asensor contains a Gaussia luciferase (Gluc and a firefly luciferase (Fluc expression cassette to sense functional miRNA and to serve as an internal control respectively. Using this array, we acquired functional profiles of 115 miRNAs for 12 cell lines and found "functional miRNA signatures" for several specific cell lines. The activities of specific miRNAs including the let-7 family, miR-17-92 cluster, miR-221, and miR-222 in HEK 293 cells were compared with their expression levels determined by quantitative reverse transcriptase polymerase chain reaction (QRT-PCR. We also demonstrate two other practical applications of the array, including a comparison of the miRNA activity between HEK293 and HEK293T cells and the ability to monitor miRNA activity changes in K562 cells treated with 12-O-tetradecanoylphorbol-13-acetate (TPA. CONCLUSIONS/SIGNIFICANCE: Our approach has potential applications in the identification of cell types, the characterization of biological and pathological processes, and the evaluation of responses to interventions.

  10. Applying a Participatory Design Approach to Define Objectives and Properties of a "Data Profiling" Tool for Electronic Health Data.

    Science.gov (United States)

    Estiri, Hossein; Lovins, Terri; Afzalan, Nader; Stephens, Kari A

    2016-01-01

    We applied a participatory design approach to define the objectives, characteristics, and features of a "data profiling" tool for primary care Electronic Health Data (EHD). Through three participatory design workshops, we collected input from potential tool users who had experience working with EHD. We present 15 recommended features and characteristics for the data profiling tool. From these recommendations we derived three overarching objectives and five properties for the tool. A data profiling tool, in Biomedical Informatics, is a visual, clear, usable, interactive, and smart tool that is designed to inform clinical and biomedical researchers of data utility and let them explore the data, while conveniently orienting the users to the tool's functionalities. We suggest that developing scalable data profiling tools will provide new capacities to disseminate knowledge about clinical data that will foster translational research and accelerate new discoveries.

  11. Characterization of silicon microstrip sensors, front-end electronics, and prototype tracking detectors for the CBM experiment at FAIR

    Energy Technology Data Exchange (ETDEWEB)

    Sorokin, Iurii

    2013-07-01

    The Compressed Baryonic Matter (CBM) experiment will explore the phase diagram of strongly interacting matter in the region of high net baryonic densities. The matter at the extreme conditions will be studied in collisions of a heavy ion beam with a fixed heavy element target. The present work is devoted to the development of the main component of the CBM experiment - the Silicon Tracking System (STS). The STS has to enable reconstruction of up to 1000 charged particle tracks per nucleus-nucleus interaction at the rate of up to 10 MHz, provide a momentum resolution Δp/p of 1 %, and withstand the radiation load of up to 10{sup 14} n{sub eq}/cm{sup 2} (n{sub eq}-neutron equivalent). The STS will be based on double-sided silicon microstrip sensors, that will be arranged in 8 planes in the aperture of the dipole magnet. Selftriggering readout electronics will be located on the periphery of the detecting planes, and connected to the sensors with low mass microcables. In the stage of R and D, as well as in the stages of pre-series and series production, characterization of the sensors, of the front-end electronics, and of the complete detector modules has to be performed. In the present work the required techniques were developed, and the performance of the latest detector prototypes was evaluated. A particular attention is paid to evaluation of the signal amplitude, as it is one of the most important detector characteristics. Techniques for measuring the passive electrical characteristics of the sensors were developed. These include: the coupling and the interstrip capacitances, the interstrip resistance, the bias resistance, the strip leakage current, the bulk capacitance, and the bulk leakage current. The techniques will be applied for the quality assurance of the sensors during the pre-series and the series production. Extensive characterization of the prototype readout chip, n-XYTER, was performed. The register settings were optimized, and the dependence of the

  12. Electron number density profiles derived from radio occultation on the CASSIOPE spacecraft

    DEFF Research Database (Denmark)

    Shume, E. B.; Vergados, P.; Komjathy, A.

    2017-01-01

    good agreement with density profiles estimated from ionosonde data, measured over nearby stations to the latitude and longitude of the RO tangent points, (2) in good agreement with density profiles inferred from GPS RO measured by the Constellation Observing System for Meteorology, Ionosphere...... number density profiles retrieved over landmasses and oceans. The density profiles over oceans exhibit wide-spread values and scale heights compared to density profiles over landmasses. We provide an explanation for the ocean-landmass discrepancy in terms of the unique wave coupling mechanisms operating...

  13. Monitoring of the current profile by using cyclotronic electron waves in tokamaks; Controle du profil de courant par ondes cyclotroniques electroniques dans les tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Dumont, R

    2001-08-01

    The subject of this thesis is the study of the cyclotronic electron wave as a monitoring tool of the current profile. The first chapter is dedicated to basic notions concerning tokamak plasmas and current generation. The second chapter is centered on the use of fast electrons to generate current and on its modelling. The propagation and absorption of the cyclotronic electron wave require a specific polarization state whose characteristics must be carefully chosen according to some parameters of the discharge, the chapter 3 deals with this topic. The absorption of a wave in a plasma depends greatly on the velocity distribution of the particles that make up the plasma and this distribution is constantly modified by the energy of the wave, so this phenomenon is non-linear and its physical description is difficult. In a case of a fusion plasma, a sophisticated approximation called quasi-linear theory can be applied with some restrictions that are presented in chapter 4. Chapters 5 and 6 are dedicated to kinetics scenarios involving the low hybrid wave and the cyclotronic electron wave inside the plasma. Some experiments dedicated to the study of the cyclotronic electron wave have been performed in Tore-supra (France) and FTU (Italy) tokamaks, they are presented in the last chapter. (A.C.)

  14. Radiation hardness of GaAs sensors against gamma-rays, neutrons and electrons

    Energy Technology Data Exchange (ETDEWEB)

    Šagátová, Andrea, E-mail: andrea.sagatova@stuba.sk [Institute of Nuclear and Physical Engineering, Faculty of Electrical Engineering and Information Technology, Slovak University of Technology, Ilkovičova 3, 812 19 Bratislava (Slovakia); University Centre of Electron Accelerators, Slovak Medical University, Ku kyselke 497, 911 06 Trenčín (Slovakia); Zaťko, Bohumír; Dubecký, František [Institute of Electrical Engineering, Slovak Academy of Sciences, Dúbravská cesta 9, 841 04 Bratislava (Slovakia); Ly Anh, Tu [Faculty of Applied Science, University of Technology VNU HCM, 268 Ly Thuong Kiet Street, District 10, Ho Chi Minh City (Viet Nam); Nečas, Vladimír; Sedlačková, Katarína; Pavlovič, Márius [Institute of Nuclear and Physical Engineering, Faculty of Electrical Engineering and Information Technology, Slovak University of Technology, Ilkovičova 3, 812 19 Bratislava (Slovakia); Fülöp, Marko [University Centre of Electron Accelerators, Slovak Medical University, Ku kyselke 497, 911 06 Trenčín (Slovakia)

    2017-02-15

    Highlights: • Radiation hardness of SI GaAs detectors against gamma-rays, neutrons and electrons was compared. • Good agreement was achieved between the experimental results and displacement damage factor of different types of radiation. • CCE and FWHM first slightly improved (by 1–8%) and just then degraded with the cumulative dose. • An increase of detection efficiency with cumulative dose was observed. - Abstract: Radiation hardness of semi-insulating GaAs detectors against {sup 60}Co gamma-rays, fast neutrons and 5 MeV electrons was compared. Slight improvements in charge collection efficiency (CCE) and energy resolution in FWHM (Full Width at Half Maximum) were observed at low doses with all kinds of radiation followed by their degradation. The effect occurred at a dose of about 10 Gy of neutrons (CCE improved by 1%, FWHM by 5% on average), at 1 kGy of electrons (FWHM decreased by 3% on average) and at 10 kGy of gamma-rays (CCE raised by 5% and FWHM dropped by 8% on average), which is in agreement with the relative displacement damage of the used types of radiation. Gamma-rays of MeV energies are 1000-times less damaging than similar neutrons and electrons about 10-times more damaging than photons. On irradiating the detectors with neutrons and electrons, we observed a global increase in their detection efficiency, which was caused probably by enlargement of the active detector area as a consequence of created radiation defects in the base material. Detectors were still functional after a dose of 1140 kGy of ∼1 MeV photons, 104 kGy of 5 MeV electrons but only up to 0.576 kGy of fast (∼2 to 30 MeV) neutrons.

  15. The X-Ray Beam Imager for Transversal Profiling of Low-Emittance Electron Beam at the SPring-8

    CERN Document Server

    Takano, S; Ohkuma, H

    2005-01-01

    We have developed the X-ray beam imager (XBI) at the accelerator diagnostics beamline I of the SPring-8 to observe transverse profiles of small electron beam of a low-emittance synchrotron light source. The XBI is based on a single Fresnel zone plate (FZP) and an X-ray zooming tube (XZT). The electron beam moving in a bending magnet is imaged by the FZP. Monochromatic X-ray is selected by a double crystal monochromator to avoid the effect of chromatic aberration of the FZP. The X-ray images of the electron beam obtained are converted by the XZT to enlarged images in visible light. The XBI has achieved a superior 1 σ spatial resolution in the micron range, and a fast time resolution of 1 ms. It has also realized a vignetting-free field of view larger than 1.5 mm in diameter on the coordinates of the electron beam, which is not easily obtained by imaging optics using two FZPs. With the XBI, we have successfully measured the profiles of the small electron beam having low vertical emittance in the pm ra...

  16. Electron transfer processes occurring on platinum neural stimulating electrodes: a tutorial on the i(V e) profile

    Science.gov (United States)

    Kumsa, Doe W.; Bhadra, Narendra; Hudak, Eric M.; Kelley, Shawn C.; Untereker, Darrel F.; Mortimer, J. Thomas

    2016-10-01

    The aim of this tutorial is to encourage members of the neuroprosthesis community to incorporate electron transfer processes into their thinking and provide them with the tools to do so when they design and work with neurostimulating devices. The focus of this article is on platinum because it is the most used electrode metal for devices in commercial use. The i(V e) profile or cyclic voltammogram contains information about electron transfer processes that can occur when the electrode-electrolyte interface, V e, is at a specific potential, and assumed to be near steady-state conditions. For the engineer/designer this means that if the potential is not in the range of a specific electron transfer process, that process cannot occur. An i(V e) profile, recorded at sweep rates greater than 0.1 mVs-1, approximates steady-state conditions. Rapid transient potential excursions, like that seen with neural stimulation pulses, may be too fast for the reaction to occur, however, this means that if the potential is in the range of a specific electron transfer process it may occur and should be considered. The approach described here can be used to describe the thermodynamic electron transfer processes on other candidate electrode metals, e.g. stainless steel, iridium, carbon-based, etc.

  17. Operation tools with dielectric elastomer pressure sensors

    Science.gov (United States)

    Böse, Holger; Müller, Dominik; Ehrlich, Johannes

    2017-04-01

    New sensors based on dielectric elastomers have recently been shown to exhibit high sensitivity for compression loads. The basic design of these sensors exhibits two profiled surfaces coated with electrode layers between which an elastomer film with the counter-electrode is confined. All components of the sensor are prepared with silicone whose stiffness can be varied in a wide range. Depending on the details of the sensor design, various effects contribute to the enhancement of the capacitance. The intermediate elastomer film is stretched upon compression, the elastomer profiles are deformed and the electrode layers on the elastomer profiles and in the elastomer film approach each other. Beside the detection of pressure, such sensors can also be used for operation tools in human-machine interfaces. To demonstrate this potential, a touch pad with six pressure-sensitive fields is presented. The corresponding sensors integrated in the touch fields detect the exerted forces of the finger, show them on a display and control the brightness of some LEDs. As a second example, the integration of sensor-based control fields on an automotive steering wheel is shown. Finally, the sensors can also be used in fabrics to control arbitrary functions of wearable electronic devices.

  18. Mitigation of the electron-cloud effect in the PSR and SNS protonstorage rings by tailoring the bunch profile

    CERN Document Server

    Pivi, M T

    2003-01-01

    For the storage ring of the Spallation Neutron Source (SNS) at Oak Ridge, and for the Proton Storage Ring (PSR) at Los Alamos, both with intense and very long bunches, the electron cloud develops primarily by the mechanism of trailing-edge multipacting. We show, by means of simulations for the PSR, how the resonant nature of this mechanism may be effectively broken by tailoring the longitudinal bunch profile at fixed bunch charge, resulting in a significant decrease in the electron-cloud effect. We briefly discuss the experimental difficulties expected in the implementation of this cure.

  19. 75 FR 63810 - Grant of Authority for Subzone Status; SICK, Inc. (Photo-Electronic Industrial Sensors...

    Science.gov (United States)

    2010-10-18

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE Foreign-Trade Zones Board Grant of Authority for Subzone Status; SICK, Inc. (Photo- Electronic Industrial... ports of entry of the United States, to expedite and encourage foreign commerce, and for other purposes...

  20. Ferrocene bound poly(vinyl chloride) as ion to electron transducer in electrochemical ion sensors.

    Science.gov (United States)

    Pawlak, Marcin; Grygolowicz-Pawlak, Ewa; Bakker, Eric

    2010-08-15

    We report here on the synthesis of poly(vinyl chloride) (PVC) covalently modified with ferrocene groups (FcPVC) and the electrochemical behavior of the resulting polymeric membranes in view of designing all solid state voltammetric ion sensors. The Huisgen cycloaddition ("click chemistry") was found to be a simple and efficient method for ferrocene attachment. A degree of PVC modification with ferrocene groups between 1.9 and 6.1 mol % was achieved. The chemical modification of the PVC backbone does not significantly affect the ion-selective properties (selectivity, mobility, and solvent casting ability) of potentiometric sensing membranes applying this polymer. Importantly, the presence of such ferrocene groups may eliminate the need for an additional redox-active layer between the membrane and the inner electric contact in all solid state sensor designs. Electrochemical doping of this system was studied in a symmetrical sandwich configuration: glassy carbon electrode |FcPVC| glassy carbon electrode. Prior electrochemical doping from aqueous solution, resulting in a partial oxidation of the ferrocene groups, was confirmed to be necessary for the sandwich configuration to pass current effectively. The results suggest that only approximately 2.3 mol % of the ferrocene groups are electrochemically accessible, likely due to surface confined electrochemical behavior in the polymer. Indeed, cyclic voltammetry of aqueous hexacyanoferrate (III) remains featureless at cathodic potentials (down to -0.5 V). This indicates that the modified membrane is not responsive to redox-active species in the sample solution, making it possible to apply this polymer as a traditional, single membrane. Yet, the redox capacity of the electrode modified with this type of membrane was more than 520 microC considering a 20 mm(2) active electrode area, which appears to be sufficient for numerous practical ion voltammetric applications. The electrode was observed to operate reproducibly, with 1

  1. Design and application of a novel high precision and low cost electronic tachogenerator for sensor-based brushless direct current motor drivers.

    Science.gov (United States)

    Ozgenel, Mehmet Cihat; Bal, Gungor; Uygun, Durmus

    2017-03-01

    This study presents a precise speed control method for Brushless Direct Current (BLDC) Motors using an electronic tachogenerator (ETg) instead of an electro-mechanical tachogenerator. Most commonly used three-phase BLDC motors have three position sensors for rotor position data to provide commutation among stator windings. Aforementioned position sensors are usually Hall-effect sensors delivering binary-high and binary-low data as long as the motor rotates. These binary sets from three Hall-effect sensors can be used as an analogue rotor speed signal for closed loop applications. Each position sensor signal is apart from 120 electrical degrees. By using an electronic circuitry, a combination of position sensor signals is converted to the analogue signal providing an input to a PI speed controller. To implement this, a frequency to voltage converter has been used in this study. Then, the analogue speed signal has been evaluated as rotor speed data in comparison with the reference speed. So, an ETg system has been successfully achieved in place of an electro-mechanical tachogenerator for BLDC motor speed control. The proposed ETg has been tested under various speed conditions on an experimental setup. Employed tests and obtained results show that the proposed low-cost speed feedback sub-system can be effectively used in BLDC motor drive systems. Through the proved method and designed sub-system, a new motor controller chip with a speed feedback capability has been aimed.

  2. An inkjet printed near isotropic 3-D antenna with embedded electronics for wireless sensor applications

    KAUST Repository

    Farooqui, Muhammad Fahad

    2014-07-01

    A 3-D (cube-shaped) antenna, which has been inkjet printed on a paper substrate and integrated with embedded electronics, is presented for the first time. A 1.5λ0 dipole is uniquely implemented on all the faces of the cube to achieve near isotropic radiation pattern. The antenna measures 13mm × 13mm × 13mm, where each side of the cube corresponds to only 0.1λ0 (at 2.4 GHz). Measurements with driving electronics placed inside the cube have shown that the antenna performance is not affected by the presence of embedded circuits. The cube antenna design is highly suitable for mobile sensing applications.

  3. The study of electronic structure and properties of silicene for gas sensor application

    Energy Technology Data Exchange (ETDEWEB)

    Wella, Sasfan A.; Syaputra, Marhamni; Wungu, Triati D. K., E-mail: triati@fi.itb.ac.id; Suprijadi [Department of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung Jl. Ganesha 10 Bandung 40132, West Java (Indonesia)

    2016-03-11

    In this study, we investigated the adsorption of gas molecules (H{sub 2}S, CO) on pristine silicene using first principles calculation. The structure, electronic properties, and adsorption energy of H{sub 2}S,CO/silicene are discussed thoroughly. We found that the pristine silicenewith low buckling structure is the most stable as compared with planar and high buckling structures. Silicene was able to detect a gas molecule which can be observed according tothe density of states analysis. Though a gas molecule adsorbed weakly, the electronic properties of the low buckling pristine silicene changed from semi-metal (zero band gap) to semiconductor. The adsorption energy of H{sub 2}S and CO on silicene is 0.075 eV and 0.06 eV, respectively.

  4. Low-Cost Soil Moisture Profile Probe Using Thin-Film Capacitors and a Capacitive Touch Sensor

    Directory of Open Access Journals (Sweden)

    Yuki Kojima

    2016-08-01

    Full Text Available Soil moisture is an important property for agriculture, but currently commercialized soil moisture sensors are too expensive for many farmers. The objective of this study is to develop a low-cost soil moisture sensor using capacitors on a film substrate and a capacitive touch integrated circuit. The performance of the sensor was evaluated in two field experiments: a grape field and a mizuna greenhouse field. The developed sensor captured dynamic changes in soil moisture at 10, 20, and 30 cm depth, with a period of 10–14 days required after sensor installation for the contact between capacitors and soil to settle down. The measured soil moisture showed the influence of individual sensor differences, and the influence masked minor differences of less than 0.05 m3·m−3 in the soil moisture at different locations. However, the developed sensor could detect large differences of more than 0.05 m3·m−3, as well as the different magnitude of changes, in soil moisture. The price of the developed sensor was reduced to 300 U.S. dollars and can be reduced even more by further improvements suggested in this study and by mass production. Therefore, the developed sensor will be made more affordable to farmers as it requires low financial investment, and it can be utilized for decision-making in irrigation.

  5. Temperature profile data from surface sensors and CTD casts from NOAA Ship DISCOVERER and other platforms as part of the Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 1981-10-22 to 1982-10-13 (NODC Accession 8400037)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile data were collected from surface sensors and CTD casts from NOAA Ship DISCOVERER and other platforms from 22 October 1981 to 13 October 1982....

  6. Temperature profile data from surface sensors, bottle casts, and CTD casts from the R/V ALPHA HELIX as part of the Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 27 July 1986 to 11 November 1987 (NODC Accession 8800064)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile data were collected from surface sensors, bottle casts, and CTD casts from the R/V ALPHA HELIX from 27 July 1986 to 11 November 1987. Data were...

  7. Temperature profile data from surface sensors, bottle casts, and CTD casts from NOAA Ship MILLER FREEMAN as part of the Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 1986-09-18 to 1987-05-14 (NODC Accession 8800019)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile data were collected from surface sensors, bottle casts, and CTD casts from NOAA Ship MILLER FREEMAN from 18 September 1986 to 14 May 1987. Data...

  8. Temperature and salinity profiles from surface sensors and CTD casts in the Gulf of Alaska from the SURVEYOR as part of the Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 21 September 1975 to 22 September 1975 (NODC Accession 7601224)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature and salinity profiles were collected from surface sensors and CTD casts in the Gulf of Alaska from the SURVEYOR. Data were collected by the Pacific...

  9. Electronic properties of Al/DNA/p-Si MIS diode: Application as temperature sensor

    Energy Technology Data Exchange (ETDEWEB)

    Guellue, O., E-mail: omergullu@gmail.com [Batman University, Science and Art Faculty, Department of Physics, 72060 Batman (Turkey); Osmaniye Korkut Ata University, Science and Art Faculty, Department of Physics, 80000 Osmaniye (Turkey); Tueruet, A. [Atatuerk University, Science Faculty, Department of Physics, 25240 Erzurum (Turkey)

    2011-01-21

    Research highlights: > This work proposes that DNA molecules should be considered, among other candidates, as a potential organic thin film for metal-interface layer-semiconductor devices. > We successfully fabricated Al/DNA/p-Si device with interlayer by a simple cast method. > The temperature is found to significantly effect the electrical properties of the Al/DNA/p-Si device. > The facts: (i) that the technology of the fabrication of a Al/DNA/p-Si Schottky diode much simpler and economical than that for the Si p-n junction and (ii) the sensibility of the Al/DNA/p-Si Schottky diode as temperature sensor is 42% higher than that of a Si p-n junction, indicate that the Al/DNA/p-Si Schottky diode is a good alternative as temperature sensor. - Abstract: The current-voltage (I-V) measurements were performed in the temperature range (200-300 K) on Al/DNA/p-Si Schottky barrier type diodes. The Schottky diode shows non-ideal I-V behaviour with ideality factors n equal to 1.34 {+-} 0.02 and 1.70 {+-} 0.02 at 300 K and 200 K, respectively, and is thought to have a metal-interface layer-semiconductor (MIS) configuration. The zero-bias barrier height {Phi}{sub b} determined from the I-V measurements was 0.75 {+-} 0.01 eV at 300 K and decreases to 0.61 {+-} 0.01 eV at 200 K. The forward voltage-temperature (V{sub F}-T) characteristics were obtained from the I-V measurements in the temperature range 200-300 K at different activation currents (I{sub F}) in the range 20 nA-6 {mu}A. The V{sub F}-T characteristics were linear for three activation currents in the diode. From the V{sub F}-T characteristics at 20 nA, 100 nA and 6 {mu}A, the values of the temperature coefficients of the forward bias voltage (dV{sub F}/dT) for the diode were determined as -2.30 mV K{sup -1}, -2.60 mV K{sup -1} and -3.26 mV K{sup -1} with a standard error of 0.05 mV K{sup -1}, respectively.

  10. The APSEL4D Monolithic Active Pixel Sensor and its Usage in a Single Electron Interference Experiment

    CERN Document Server

    Alberghi, Gian Luigi

    We have realized a Data Acquisition chain for the use and characterization of APSEL4D, a 32 x 128 Monolithic Active Pixel Sensor, developed as a prototype for frontier experiments in high energy particle physics. In particular a transition board was realized for the conversion between the chip and the FPGA voltage levels and for the signal quality enhancing. A Xilinx Spartan-3 FPGA was used for real time data processing, for the chip control and the communication with a Personal Computer through a 2.0 USB port. For this purpose a firmware code, developed in VHDL language, was written. Finally a Graphical User Interface for the online system monitoring, hit display and chip control, based on windows and widgets, was realized developing a C++ code and using Qt and Qwt dedicated libraries. APSEL4D and the full acquisition chain were characterized for the first time with the electron beam of the transmission electron microscope and with 55Fe and 90Sr radioactive sources. In addition, a beam test was performed at ...

  11. Mapping electrostatic profiles across axial p-n junctions in Si nanowires using off-axis electron holography

    Science.gov (United States)

    Gan, Zhaofeng; Perea, Daniel E.; Yoo, Jinkyoung; Tom Picraux, S.; Smith, David J.; McCartney, Martha R.

    2013-10-01

    Si nanowires (NWs) with axial p-n junctions were grown by the vapor-liquid-solid method. Transmission electron microscopy and electron holography were used to characterize the microstructure and electrostatic properties. Measurement of the potential profile showed the presence of a p-n junction with a height of 1.0 ± 0.3 V. A Schottky barrier was observed at the end of the NW due to the Au catalyst particle. Comparison with simulations indicated dopant concentrations of 1019 cm-3 for donors and 1017 cm-3 for acceptors. These results confirm the benefit of combining off-axis electron holography with simulations for determining localized information about the electrically active dopant distributions in nanowire structures.

  12. Mapping Electrostatic Profiles Across Axial p-n Junctions in Si Nanowires using Off-Axis Electron Holography

    Energy Technology Data Exchange (ETDEWEB)

    Gan, Zhaofeng; Perea, Daniel E.; Yoo, Jinkyoung; Picraux, Samuel T.; Smith, David J.; Mccartney, Martha R.

    2013-10-07

    Si nanowires (NWs) with axial p-n junctions were grown by the vapor-liquid-solid method. Transmission electron microscopy and electron holography were used to characterize the microstructure and electrostatic properties. Measurement of the potential profile showed the presence of a p-n junction with a height of 1.0±0.3V. A Schottky barrier was observed at the end of the NW due to the Au catalyst particle. Comparison with simulations indicated dopant concentrations of 1019cm-3 for donors and 1017cm-3 for acceptors. These results confirm the benefit of combining off-axis electron holography with simulations for determining localized information about the electrically active dopant distributions in nanowire structures.

  13. Radio science electron density profiles of lunar ionosphere based on the service module of circumlunar return and reentry spacecraft

    Science.gov (United States)

    Wang, M.; Han, S.; Ping, J.; Tang, G.; Zhang, Q.

    2017-09-01

    The existence of lunar ionosphere has been under debate for a long time. Radio occultation experiments had been performed by both Luna 19/22 and SELENE missions and electron column density of lunar ionosphere was provided. The Apollo 14 mission also acquired the electron density with in situ measurements. But the results of these missions don't well-matched. In order to explore the lunar ionosphere, radio occultation with the service module of Chinese circumlunar return and reentry spacecraft has been performing. One coherent S-band and X-band radio signals were recorded by China deep space stations, and local correlation was adopted to compute carrier phases of both signals. Based on the above work, the electron density profiles of lunar ionosphere was obtained and analyzed.

  14. Sensors in Smart Phone

    OpenAIRE

    Pei, Chunmei; Guo, Huiling; Yang, Xiuqing; Wang, Yangqiu; Zhang, Xiaojing; Ye, Hairong

    2010-01-01

    International audience; The technological innovation in electronics makes nowadays mobile phone more than a simple communication tool: it becomes a portable electronic device with integrated functions, such as listening to music, watching movies, taking photos, etc. To achieve these, many kinds of advanced sensor are used. In this paper, several applications of sensor in smart phone are introduced including Image Sensor, Fingerprint Identification Sensor, Photo-electric Sensor, Acceleration S...

  15. Primary events in the blue light sensor plant cryptochrome: intraprotein electron and proton transfer revealed by femtosecond spectroscopy.

    Science.gov (United States)

    Immeln, Dominik; Weigel, Alexander; Kottke, Tilman; Pérez Lustres, J Luis

    2012-08-01

    Photoreceptors are chromoproteins that undergo fast conversion from dark to signaling states upon light absorption by the chromophore. The signaling state starts signal transduction in vivo and elicits a biological response. Therefore, photoreceptors are ideally suited for analysis of protein activation by time-resolved spectroscopy. We focus on plant cryptochromes which are blue light sensors regulating the development and daily rhythm of plants. The signaling state of these flavoproteins is the neutral radical of the flavin chromophore. It forms on the microsecond time scale after light absorption by the oxidized state. We apply here femtosecond broad-band transient absorption to early stages of signaling-state formation in a plant cryptochrome from the green alga Chlamydomonas reinhardtii. Transient spectra show (i) subpicosecond decay of flavin-stimulated emission and (ii) further decay of signal until 100 ps delay with nearly constant spectral shape. The first decay (i) monitors electron transfer from a nearby tryptophan to the flavin and occurs with a time constant of τ(ET) = 0.4 ps. The second decay (ii) is analyzed by spectral decomposition and occurs with a characteristic time constant τ(1) = 31 ps. We reason that hole transport through a tryptophan triad to the protein surface and partial deprotonation of tryptophan cation radical hide behind τ(1). These processes are probably governed by vibrational cooling. Spectral decomposition is used together with anisotropy to obtain the relative orientation of flavin and the final electron donor. This narrows the number of possible electron donors down to two tryptophans. Structural analysis suggests that a set of histidines surrounding the terminal tryptophan may act as proton acceptor and thereby stabilize the radical pair on a 100 ps time scale.

  16. Electron spin relaxation can enhance the performance of a cryptochrome-based magnetic compass sensor

    DEFF Research Database (Denmark)

    Kattnig, Daniel R; Sowa, Jakub K; Solov'yov, Ilia A

    2016-01-01

    The radical pair model of the avian magnetoreceptor relies on long-lived electron spin coherence. Dephasing, resulting from interactions of the spins with their fluctuating environment, is generally assumed to degrade the sensitivity of this compass to the direction of the Earth's magnetic field....... Here we argue that certain spin relaxation mechanisms can enhance its performance. We focus on the flavin-tryptophan radical pair in cryptochrome, currently the only candidate magnetoreceptor molecule. Correlation functions for fluctuations in the distance between the two radicals in Arabidopsis...... thaliana cryptochrome 1 were obtained from molecular dynamics (MD) simulations and used to calculate the spin relaxation caused by modulation of the exchange and dipolar interactions. We find that intermediate spin relaxation rates afford substantial enhancements in the sensitivity of the reaction yields...

  17. NOAA JPSS Ozone Mapping and Profiler Suite (OMPS) Nadir Total Column Sensor Data Record (SDR) from IDPS

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Ozone Mapping and Profiler Suite (OMPS) onboard the Suomi NPP satellite monitors ozone from space. OMPS will collect total column and vertical profile ozone data...

  18. Radial Profiles of the Plasma Electron Characteristics in a 30 kW Arc Jet

    Science.gov (United States)

    Codron, Douglas A.; Nawaz, Anuscheh

    2013-01-01

    The present effort aims to strengthen modeling work conducted at the NASA Ames Research Center by measuring the critical plasma electron characteristics within and slightly outside of an arc jet plasma column. These characteristics are intended to give physical insights while assisting in the formulation of boundary conditions to validate full scale simulations. Single and triple Langmuir probes have been used to achieve estimates of the electron temperature (T(sub e)), electron number density (n(sub e)) and plasma potential (outside of the plasma column) as probing location is varied radially from the flow centerline. Both the electron temperature and electron number density measurements show a large dependence on radial distance from the plasma column centerline with T(sub e) approx. = (3 - 12 eV and n(sub e) approx. = 10(exp 12) - 10(exp 14)/cu cm.

  19. Design and Implementation of an Electronic Front-End Based on Square Wave Excitation for Ultrasonic Torsional Guided Wave Viscosity Sensor.

    Science.gov (United States)

    Rabani, Amir

    2016-10-12

    The market for process instruments generally requires low cost devices that are robust, small in size, portable, and usable in-plant. Ultrasonic torsional guided wave sensors have received much attention by researchers for measurement of viscosity and/or density of fluids in recent years. The supporting electronic systems for these sensors providing many different settings of sine-wave signals are bulky and expensive. In contrast, a system based on bursts of square waves instead of sine waves would have a considerable advantage in that respect and could be built using simple integrated circuits at a cost that is orders of magnitude lower than for a windowed sine wave device. This paper explores the possibility of using square wave bursts as the driving signal source for the ultrasonic torsional guided wave viscosity sensor. A simple design of a compact and fully automatic analogue square wave front-end for the sensor is also proposed. The successful operation of the system is demonstrated by using the sensor for measuring the viscosity in a representative fluid. This work provides the basis for design and manufacture of low cost compact standalone ultrasonic guided wave sensors and enlightens the possibility of using coded excitation techniques utilising square wave sequences in such applications.

  20. Soft, stretchable, epidermal sensor with integrated electronics and photochemistry for measuring personal UV exposures.

    Science.gov (United States)

    Shi, Yunzhou; Manco, Megan; Moyal, Dominique; Huppert, Gil; Araki, Hitoshi; Banks, Anthony; Joshi, Hemant; McKenzie, Richard; Seewald, Alex; Griffin, Guy; Sen-Gupta, Ellora; Wright, Donald; Bastien, Philippe; Valceschini, Florent; Seité, Sophie; Wright, John A; Ghaffari, Roozbeh; Rogers, John; Balooch, Guive; Pielak, Rafal M

    2018-01-01

    Excessive ultraviolet (UV) radiation induces acute and chronic effects on the skin, eye and immune system. Personalized monitoring of UV radiation is thus paramount to measure the extent of personal sun exposure, which could vary with environment, lifestyle, and sunscreen use. Here, we demonstrate an ultralow modulus, stretchable, skin-mounted UV patch that measures personal UV doses. The patch contains functional layers of ultrathin stretchable electronics and a photosensitive patterned dye that reacts to UV radiation. Color changes in the photosensitive dyes correspond to UV radiation intensity and are analyzed with a smartphone camera. A software application has feature recognition, lighting condition correction, and quantification algorithms that detect and quantify changes in color. These color changes are then correlated with corresponding shifts in UV dose, and compared to existing UV dose risk levels. The soft mechanics of the UV patch allow for multi-day wear in the presence of sunscreen and water. Two evaluation studies serve to demonstrate the utility of the UV patch during daily activities with and without sunscreen application.

  1. Plasmons and Electrons as Nanosecond-Fast Sensors for Scanning Tunneling Microscopy

    Science.gov (United States)

    Loth, Sebastian

    2014-03-01

    The ability to measure the fast dynamical evolution of atomic-scale systems often holds the key to their understanding. We combine fast pump-probe spectroscopy tools with low-temperature scanning tunneling microscopy to study atomically assembled arrays of magnetic atoms. The dynamical information quantifies spin lifetimes, magnetic stability and even allows identifying the cross-over between quantum spins and classical magnetism. The spin relaxation times of transition metal atoms can be measured by all-electronic pump probe spectroscopy in which nanosecond-fast voltage pulses excite the spins and probe the average time-dependent response by variations in the spin-polarized tunnel current. In addition, the fast evolution of the local electrostatic potential can be mapped by detecting plasmonic light emission from the STM tunnel junction with time correlating single photon counting. The combination of electrical stimulus and optical detection provides precise control of the excitation process of individual atoms enabling new experiments to probe charge and spin dynamics in the scanning tunneling microscope.

  2. Aluminum gallium nitride (GaN)/GaN high electron mobility transistor-based sensors for glucose detection in exhaled breath condensate.

    Science.gov (United States)

    Chu, Byung Hwan; Kang, Byoung Sam; Hung, Sheng Chun; Chen, Ke Hung; Ren, Fan; Sciullo, Andrew; Gila, Brent P; Pearton, Stephen J

    2010-01-01

    Immobilized aluminum gallium nitride (AlGaN)/GaN high electron mobility transistors (HEMTs) have shown great potential in the areas of pH, chloride ion, and glucose detection in exhaled breath condensate (EBC). HEMT sensors can be integrated into a wireless data transmission system that allows for remote monitoring. This technology offers the possibility of using AlGaN/GaN HEMTs for extended investigations of airway pathology of detecting glucose in EBC without the need for clinical visits. HEMT structures, consisting of a 3-microm-thick undoped GaN buffer, 30-A-thick Al(0.3)Ga(0.7)N spacer, and 220-A-thick silicon-doped Al(0.3)Ga(0.7)N cap layer, were used for fabricating the HEMT sensors. The gate area of the pH, chloride ion, and glucose detection was immobilized with scandium oxide (Sc(2)O(3)), silver chloride (AgCl) thin film, and zinc oxide (ZnO) nanorods, respectively. The Sc(2)O(3)-gated sensor could detect the pH of solutions ranging from 3 to 10 with a resolution of approximately 0.1 pH. A chloride ion detection limit of 10(-8) M was achieved with a HEMT sensor immobilized with the AgCl thin film. The drain-source current of the ZnO nanorod-gated AlGaN/GaN HEMT sensor immobilized with glucose oxidase showed a rapid response of less than 5 seconds when the sensor was exposed to the target glucose in a buffer with a pH value of 7.4. The sensor could detect a wide range of concentrations from 0.5 nM to 125 microM. There is great promise for using HEMT-based sensors to enhance the detection sensitivity for glucose detection in EBC. Depending on the immobilized material, HEMT-based sensors can be used for sensing different materials. These electronic detection approaches with rapid response and good repeatability show potential for the investigation of airway pathology. The devices can also be integrated into a wireless data transmission system for remote monitoring applications. This sensor technology could use the exhaled breath condensate to measure the

  3. Efficient analysis of mode profiles in elliptical microcavity using dynamic-thermal electron-quantum medium FDTD method.

    Science.gov (United States)

    Khoo, E H; Ahmed, I; Goh, R S M; Lee, K H; Hung, T G G; Li, E P

    2013-03-11

    The dynamic-thermal electron-quantum medium finite-difference time-domain (DTEQM-FDTD) method is used for efficient analysis of mode profile in elliptical microcavity. The resonance peak of the elliptical microcavity is studied by varying the length ratio. It is observed that at some length ratios, cavity mode is excited instead of whispering gallery mode. This depicts that mode profiles are length ratio dependent. Through the implementation of the DTEQM-FDTD on graphic processing unit (GPU), the simulation time is reduced by 300 times as compared to the CPU. This leads to an efficient optimization approach to design microcavity lasers for wide range of applications in photonic integrated circuits.

  4. Self-consistent electronic structure and segregation profiles of the Cu-Ni (001) random-alloy surface

    DEFF Research Database (Denmark)

    Ruban, Andrei; Abrikosov, I. A.; Kats, D. Ya.

    1994-01-01

    We have calculated the electronic structure and segregation profiles of the (001) surface of random Cu-Ni alloys with varying bulk concentrations by means of the coherent potential approximation and the linear muffin-tin-orbitals method. Exchange and correlation were included within the local......-density approximation. Temperature effects were accounted for by means of the cluster-variation method and, for comparison, by mean-field theory. The necessary interaction parameters were calculated by the Connolly-Williams method generalized to the case of a surface of a random alloy. We find the segregation profiles...... to be oscillatory with a strong preference for Cu to segregate towards the surface of the alloy....

  5. Influence of age and gender on the profile of exhaled volatile organic compounds analyzed by an electronic nose

    Directory of Open Access Journals (Sweden)

    Silvano Dragonieri

    2016-04-01

    Full Text Available We aimed to investigate the effects of age and gender on the profile of exhaled volatile organic compounds. We evaluated 68 healthy adult never-smokers, comparing them by age and by gender. Exhaled breath samples were analyzed by an electronic nose (e-nose, resulting in "breathprints". Principal component analysis and canonical discriminant analysis showed that older subjects (≥ 50 years of age could not be distinguished from younger subjects on the basis of their breathprints, as well as that the breathprints of males could not distinguished from those of females (cross-validated accuracy, 60.3% and 57.4%, respectively.Therefore, age and gender do not seem to affect the overall profile of exhaled volatile organic compounds measured by an e-nose.

  6. Ultrasonic fingerprint sensor using a piezoelectric micromachined ultrasonic transducer array integrated with complementary metal oxide semiconductor electronics

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Y.; Fung, S.; Wang, Q.; Horsley, D. A. [Berkeley Sensor and Actuator Center, University of California, Davis, 1 Shields Avenue, Davis, California 95616 (United States); Tang, H.; Boser, B. E. [Berkeley Sensor and Actuator Center, University of California, Berkeley, California 94720 (United States); Tsai, J. M.; Daneman, M. [InvenSense, Inc., 1745 Technology Drive, San Jose, California 95110 (United States)

    2015-06-29

    This paper presents an ultrasonic fingerprint sensor based on a 24 × 8 array of 22 MHz piezoelectric micromachined ultrasonic transducers (PMUTs) with 100 μm pitch, fully integrated with 180 nm complementary metal oxide semiconductor (CMOS) circuitry through eutectic wafer bonding. Each PMUT is directly bonded to a dedicated CMOS receive amplifier, minimizing electrical parasitics and eliminating the need for through-silicon vias. The array frequency response and vibration mode-shape were characterized using laser Doppler vibrometry and verified via finite element method simulation. The array's acoustic output was measured using a hydrophone to be ∼14 kPa with a 28 V input, in reasonable agreement with predication from analytical calculation. Pulse-echo imaging of a 1D steel grating is demonstrated using electronic scanning of a 20 × 8 sub-array, resulting in 300 mV maximum received amplitude and 5:1 contrast ratio. Because the small size of this array limits the maximum image size, mechanical scanning was used to image a 2D polydimethylsiloxane fingerprint phantom (10 mm × 8 mm) at a 1.2 mm distance from the array.

  7. A Multi-Channel Opto-Electronic Sensor to Accurately Monitor Heart Rate against Motion Artefact during Exercise

    Directory of Open Access Journals (Sweden)

    Abdullah Alzahrani

    2015-10-01

    Full Text Available This study presents the use of a multi-channel opto-electronic sensor (OEPS to effectively monitor critical physiological parameters whilst preventing motion artefact as increasingly demanded by personal healthcare. The aim of this work was to study how to capture the heart rate (HR efficiently through a well-constructed OEPS and a 3-axis accelerometer with wireless communication. A protocol was designed to incorporate sitting, standing, walking, running and cycling. The datasets collected from these activities were processed to elaborate sport physiological effects. t-test, Bland-Altman Agreement (BAA, and correlation to evaluate the performance of the OEPS were used against Polar and Mio-Alpha HR monitors. No differences in the HR were found between OEPS, and either Polar or Mio-Alpha (both p > 0.05; a strong correlation was found between Polar and OEPS (r: 0.96, p < 0.001; the bias of BAA 0.85 bpm, the standard deviation (SD 9.20 bpm, and the limits of agreement (LOA from −17.18 bpm to +18.88 bpm. For the Mio-Alpha and OEPS, a strong correlation was found (r: 0.96, p < 0.001; the bias of BAA 1.63 bpm, SD 8.62 bpm, LOA from −15.27 bpm to +18.58 bpm. These results demonstrate the OEPS to be capable of carrying out real time and remote monitoring of heart rate.

  8. Electronic Characterization of Au/DNA/ITO Metal-Semiconductor-Metal Diode and Its Application as a Radiation Sensor.

    Directory of Open Access Journals (Sweden)

    Hassan Maktuff Jaber Al-Ta'ii

    Full Text Available Deoxyribonucleic acid or DNA molecules expressed as double-stranded (DSS negatively charged polymer plays a significant role in electronic states of metal/silicon semiconductor structures. Electrical parameters of an Au/DNA/ITO device prepared using self-assembly method was studied by using current-voltage (I-V characteristic measurements under alpha bombardment at room temperature. The results were analyzed using conventional thermionic emission model, Cheung and Cheung's method and Norde's technique to estimate the barrier height, ideality factor, series resistance and Richardson constant of the Au/DNA/ITO structure. Besides demonstrating a strongly rectifying (diode characteristic, it was also observed that orderly fluctuations occur in various electrical parameters of the Schottky structure. Increasing alpha radiation effectively influences the series resistance, while the barrier height, ideality factor and interface state density parameters respond linearly. Barrier height determined from I-V measurements were calculated at 0.7284 eV for non-radiated, increasing to about 0.7883 eV in 0.036 Gy showing an increase for all doses. We also demonstrate the hypersensitivity phenomena effect by studying the relationship between the series resistance for the three methods, the ideality factor and low-dose radiation. Based on the results, sensitive alpha particle detectors can be realized using Au/DNA/ITO Schottky junction sensor.

  9. Density profiles of different negative ion mass groups at Titan as observed by Cassini's CAPS electron spectrometer

    Science.gov (United States)

    Wellbrock, A.; Coates, A. J.; Jones, G. H.; Waite, J. H.

    2013-12-01

    The discovery of heavy negative ions by Cassini's CAPS electron spectrometer (ELS) in Titan's ionosphere (Coates et al., 2007, Waite et al., 2007) suggests that complex hydrocarbon and nitrile processes occur in Titan's upper atmosphere which are also linked to haze formation. Negative ions are observed during Titan encounters at altitudes different mass groups as reported by Coates et al. (2007). These have been updated by Wellbrock et al. (2013) who performed a study investigating trends of mass groups with altitude using data from 34 negative ion encounters. We continue this work here by studying individual flybys in more detail. We investigate density profiles for different mass groups and total densities.

  10. Room temperature Compton profiles of conduction electrons in α-Ga ...

    Indian Academy of Sciences (India)

    B P PANDA and N C MOHAPATRA*. Department of Physics, Chikiti Mahavidyalaya, Chikiti 761 010, India. £Department of Physics, Berhampur University, Berhampur 760 007, India. Email: ncmphy123@hotmail.com. MS received 18 January 2003; accepted 21 June 2003. Abstract. Room temperature Compton profiles of ...

  11. Spatial profiles of electron and metastable atom densities in positive polarity fast ionization waves sustained in helium

    Energy Technology Data Exchange (ETDEWEB)

    Weatherford, Brandon R., E-mail: brweathe@gmail.com, E-mail: zax@esi-group.com, E-mail: evbarna@sandia.gov, E-mail: mjkush@umich.edu; Barnat, E. V., E-mail: brweathe@gmail.com, E-mail: zax@esi-group.com, E-mail: evbarna@sandia.gov, E-mail: mjkush@umich.edu [Sandia National Laboratories, Albuquerque, New Mexico 87185-1423 (United States); Xiong, Zhongmin, E-mail: brweathe@gmail.com, E-mail: zax@esi-group.com, E-mail: evbarna@sandia.gov, E-mail: mjkush@umich.edu; Kushner, Mark J., E-mail: brweathe@gmail.com, E-mail: zax@esi-group.com, E-mail: evbarna@sandia.gov, E-mail: mjkush@umich.edu [Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, Michigan 48109-2122, USA. (United States)

    2014-09-14

    Fast ionization waves (FIWs), often generated with high voltage pulses over nanosecond timescales, are able to produce large volumes of ions and excited states at moderate pressures. The mechanisms of FIW propagation were experimentally and computationally investigated to provide insights into the manner in which these large volumes are excited. The two-dimensional structure of electron and metastable densities produced by short-pulse FIWs sustained in helium were measured using laser-induced fluorescence and laser collision-induced fluorescence diagnostics for times of 100–120 ns after the pulse, as the pressure was varied from 1 to 20 Torr. A trend of center-peaked to volume-filling to wall-peaked electron density profiles was observed as the pressure was increased. Instantaneous FIW velocities, obtained from plasma-induced emission, ranged from 0.1 to 3×10⁹cm s⁻¹, depending on distance from the high voltage electrode and pressure. Predictions from two-dimensional modeling of the propagation of a single FIW correlated well with the experimental trends in electron density profiles and wave velocity. Results from the model show that the maximum ionization rate occurs in the wavefront, and the discharge continues to propagate forward after the removal of high voltage from the powered electrode due to the potential energy stored in the space charge. As the pressure is varied, the radial distribution of the ionization rate is shaped by changes in the electron mean free path, and subsequent localized electric field enhancement at the walls or on the centerline of the discharge.

  12. High time resolution reconstruction of electron temperature profiles with a neural network in C-2U

    Science.gov (United States)

    Player, Gabriel; Magee, Richard; Trask, Erik; Korepanov, Sergey; Clary, Ryan; Tri Alpha Energy Team

    2017-10-01

    One of the most important parameters governing fast ion dynamics in a plasma is the electron temperature, as the fast ion-electron collision rate goes as νei Te3 / 2 . Unfortunately, the electron temperature is difficult to directly measure-methods relying on high-powered laser pulses or fragile probes lead to limited time resolution or measurements restricted to the edge. In order to rectify the lack of time resolution on the Thomson scattering data in the core, a type of learning algorithm, specifically a neural network, was implemented. This network uses 3 hidden layers to correlate information from nearly 250 signals, including magnetics, interferometers, and several arrays of bolometers, with Thomson scattering data over the entire C-2U database, totalling nearly 20,000 samples. The network uses the Levenberg-Marquardt algorithm with Bayesian regularization to learn from the large number of samples and inputs how to accurately reconstruct the entire electron temperature time history at a resolution of 500 kHz, a huge improvement over the 2 time points per shot provided by Thomson scattering. These results can be used in many different types of analysis and plasma characterization-in this work, we use the network to quantify electron heating.

  13. Profile structures of the voltage-sensor domain and the voltage-gated K+-channel vectorially oriented in a single phospholipid bilayer membrane at the solid-vapor and solid-liquid interfaces determined by x-ray interferometry

    Science.gov (United States)

    Gupta, S.; Liu, J.; Strzalka, J.; Blasie, J. K.

    2011-09-01

    One subunit of the prokaryotic voltage-gated potassium ion channel from Aeropyrum pernix (KvAP) is comprised of six transmembrane α helices, of which S1-S4 form the voltage-sensor domain (VSD) and S5 and S6 contribute to the pore domain (PD) of the functional homotetramer. However, the mechanism of electromechanical coupling interconverting the closed-to-open (i.e., nonconducting-to-K+-conducting) states remains undetermined. Here, we have vectorially oriented the detergent (OG)-solubilized VSD in single monolayers by two independent approaches, namely “directed-assembly” and “self-assembly,” to achieve a high in-plane density. Both utilize Ni coordination chemistry to tether the protein to an alkylated inorganic surface via its C-terminal His6 tag. Subsequently, the detergent is replaced by phospholipid (POPC) via exchange, intended to reconstitute a phospholipid bilayer environment for the protein. X-ray interferometry, in which interference with a multilayer reference structure is used to both enhance and phase the specular x-ray reflectivity from the tethered single membrane, was used to determine directly the electron density profile structures of the VSD protein solvated by detergent versus phospholipid, and with either a moist He (moderate hydration) or bulk aqueous buffer (high hydration) environment to preserve a native structure conformation. Difference electron density profiles, with respect to the multilayer substrate itself, for the VSD-OG monolayer and VSD-POPC membranes at both the solid-vapor and solid-liquid interfaces, reveal the profile structures of the VSD protein dominating these profiles and further indicate a successful reconstitution of a lipid bilayer environment. The self-assembly approach was similarly extended to the intact full-length KvAP channel for comparison. The spatial extent and asymmetry in the profile structures of both proteins confirm their unidirectional vectorial orientation within the reconstituted membrane and

  14. Antipsychotic treatment dosing profile in patients with schizophrenia evaluated with electronic monitoring (MEMS®).

    Science.gov (United States)

    Acosta, Francisco J; Ramallo-Fariña, Yolanda; Bosch, Esperanza; Mayans, Teresa; Rodríguez, Carlos J; Caravaca, Ana

    2013-05-01

    Although the Medication Event Monitoring System (MEMS®) device offers accurate information on treatment dosing profile, such profile has never been studied in patients with schizophrenia. Enhancing our knowledge on this issue would help in developing intervention strategies to improve adherence to antipsychotic treatment in these patients. 74 outpatients with schizophrenia were monitored with the MEMS device for a 3-month period, for evaluation of antipsychotic treatment dosing profile, possible influence of medication schedule-related variables, adherence to treatment--considering dose intake within prescribed timeframes--and possible Hawthorne's effect of using the MEMS device. Dose-omission gaps occurred in 18.7% of monitoring days, most frequently during weekends, almost significantly. Almost one-third of prescribed doses were taken out of prescribed time. Neither the prescribed number of daily doses nor the indicated time of the day for dose intake (breakfast, dinner), were associated with correct antipsychotic dosing. Excess-dose was rare in general, and more frequent out of prescribed dose timeframe. No Hawthorne's effect was found for the MEMS device. Adherence reached only 35% according to a definition that included dose intake within prescribed timeframes. Antipsychotic treatment dosing was considerably irregular among patients with schizophrenia. Strategies to reduce dose-omission gaps and increase dosing within prescribed timeframes seem to be necessary. Gaining knowledge on precise oral antipsychotic dosing profiles or the influence of schedule-related variables may be useful to design strategies towards enhancing adherence. There appears to be no Hawthorne's effect associated with the use of MEMS devices in outpatients with schizophrenia. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Discrimination Method of the Volatiles from Fresh Mushrooms by an Electronic Nose Using a Trapping System and Statistical Standardization to Reduce Sensor Value Variation

    Science.gov (United States)

    Fujioka, Kouki; Shimizu, Nobuo; Manome, Yoshinobu; Ikeda, Keiichi; Yamamoto, Kenji; Tomizawa, Yasuko

    2013-01-01

    Electronic noses have the benefit of obtaining smell information in a simple and objective manner, therefore, many applications have been developed for broad analysis areas such as food, drinks, cosmetics, medicine, and agriculture. However, measurement values from electronic noses have a tendency to vary under humidity or alcohol exposure conditions, since several types of sensors in the devices are affected by such variables. Consequently, we show three techniques for reducing the variation of sensor values: (1) using a trapping system to reduce the infering components; (2) performing statistical standardization (calculation of z-score); and (3) selecting suitable sensors. With these techniques, we discriminated the volatiles of four types of fresh mushrooms: golden needle (Flammulina velutipes), white mushroom (Agaricus bisporus), shiitake (Lentinus edodes), and eryngii (Pleurotus eryngii) among six fresh mushrooms (hen of the woods (Grifola frondosa), shimeji (Hypsizygus marmoreus) plus the above mushrooms). Additionally, we succeeded in discrimination of white mushroom, only comparing with artificial mushroom flavors, such as champignon flavor and truffle flavor. In conclusion, our techniques will expand the options to reduce variations in sensor values. PMID:24233028

  16. Discrimination Method of the Volatiles from Fresh Mushrooms by an Electronic Nose Using a Trapping System and Statistical Standardization to Reduce Sensor Value Variation

    Directory of Open Access Journals (Sweden)

    Kouki Fujioka

    2013-11-01

    Full Text Available Electronic noses have the benefit of obtaining smell information in a simple and objective manner, therefore, many applications have been developed for broad analysis areas such as food, drinks, cosmetics, medicine, and agriculture. However, measurement values from electronic noses have a tendency to vary under humidity or alcohol exposure conditions, since several types of sensors in the devices are affected by such variables. Consequently, we show three techniques for reducing the variation of sensor values: (1 using a trapping system to reduce the infering components; (2 performing statistical standardization (calculation of z-score; and (3 selecting suitable sensors. With these techniques, we discriminated the volatiles of four types of fresh mushrooms: golden needle (Flammulina velutipes, white mushroom (Agaricus bisporus, shiitake (Lentinus edodes, and eryngii (Pleurotus eryngii among six fresh mushrooms (hen of the woods (Grifola frondosa, shimeji (Hypsizygus marmoreus plus the above mushrooms. Additionally, we succeeded in discrimination of white mushroom, only comparing with artificial mushroom flavors, such as champignon flavor and truffle flavor. In conclusion, our techniques will expand the options to reduce variations in sensor values.

  17. A New Inversion Routine to Produce Vertical Electron-Density Profiles from Ionospheric Topside-Sounder Data

    Science.gov (United States)

    Wang, Yongli; Benson, Robert F.

    2011-01-01

    Two software applications have been produced specifically for the analysis of some million digital topside ionograms produced by a recent analog-to-digital conversion effort of selected analog telemetry tapes from the Alouette-2, ISIS-1 and ISIS-2 satellites. One, TOPIST (TOPside Ionogram Scalar with True-height algorithm) from the University of Massachusetts Lowell, is designed for the automatic identification of the topside-ionogram ionospheric-reflection traces and their inversion into vertical electron-density profiles Ne(h). TOPIST also has the capability of manual intervention. The other application, from the Goddard Space Flight Center based on the FORTRAN code of John E. Jackson from the 1960s, is designed as an IDL-based interactive program for the scaling of selected digital topside-sounder ionograms. The Jackson code has also been modified, with some effort, so as to run on modern computers. This modification was motivated by the need to scale selected ionograms from the millions of Alouette/ISIS topside-sounder ionograms that only exist on 35-mm film. During this modification, it became evident that it would be more efficient to design a new code, based on the capabilities of present-day computers, than to continue to modify the old code. Such a new code has been produced and here we will describe its capabilities and compare Ne(h) profiles produced from it with those produced by the Jackson code. The concept of the new code is to assume an initial Ne(h) and derive a final Ne(h) through an iteration process that makes the resulting apparent-height profile fir the scaled values within a certain error range. The new code can be used on the X-, O-, and Z-mode traces. It does not assume any predefined profile shape between two contiguous points, like the exponential rule used in Jackson s program. Instead, Monotone Piecewise Cubic Interpolation is applied in the global profile to keep the monotone nature of the profile, which also ensures better smoothness

  18. The DEPFET Sensor-Amplifier Structure: A Method to Beat 1/f Noise and Reach Sub-Electron Noise in Pixel Detectors

    Directory of Open Access Journals (Sweden)

    Gerhard Lutz

    2016-04-01

    Full Text Available Depleted field effect transistors (DEPFET are used to achieve very low noise signal charge readout with sub-electron measurement precision. This is accomplished by repeatedly reading an identical charge, thereby suppressing not only the white serial noise but also the usually constant 1/f noise. The repetitive non-destructive readout (RNDR DEPFET is an ideal central element for an active pixel sensor (APS pixel. The theory has been derived thoroughly and results have been verified on RNDR-DEPFET prototypes. A charge measurement precision of 0.18 electrons has been achieved. The device is well-suited for spectroscopic X-ray imaging and for optical photon counting in pixel sensors, even at high photon numbers in the same cell.

  19. Data Resource Profile: Cardiovascular disease research using linked bespoke studies and electronic health records (CALIBER)

    Science.gov (United States)

    Denaxas, Spiros C; George, Julie; Herrett, Emily; Shah, Anoop D; Kalra, Dipak; Hingorani, Aroon D; Kivimaki, Mika; Timmis, Adam D; Smeeth, Liam; Hemingway, Harry

    2012-01-01

    The goal of cardiovascular disease (CVD) research using linked bespoke studies and electronic health records (CALIBER) is to provide evidence to inform health care and public health policy for CVDs across different stages of translation, from discovery, through evaluation in trials to implementation, where linkages to electronic health records provide new scientific opportunities. The initial approach of the CALIBER programme is characterized as follows: (i) Linkages of multiple electronic heath record sources: examples include linkages between the longitudinal primary care data from the Clinical Practice Research Datalink, the national registry of acute coronary syndromes (Myocardial Ischaemia National Audit Project), hospitalization and procedure data from Hospital Episode Statistics and cause-specific mortality and social deprivation data from the Office of National Statistics. Current cohort analyses involve a million people in initially healthy populations and disease registries with ∼105 patients. (ii) Linkages of bespoke investigator-led cohort studies (e.g. UK Biobank) to registry data (e.g. Myocardial Ischaemia National Audit Project), providing new means of ascertaining, validating and phenotyping disease. (iii) A common data model in which routine electronic health record data are made research ready, and sharable, by defining and curating with meta-data >300 variables (categorical, continuous, event) on risk factors, CVDs and non-cardiovascular comorbidities. (iv) Transparency: all CALIBER studies have an analytic protocol registered in the public domain, and data are available (safe haven model) for use subject to approvals. For more information, e-mail s.denaxas@ucl.ac.uk PMID:23220717

  20. Improved electron beam weld design and control with beam current profile measurements

    Science.gov (United States)

    Giedt, Warren H.

    The determination of machine settings for making an electron beam weld still involves trial and error tests. Also, even after settings are selected, serious variations in penetration may occur. Results are presented to demonstrate that improved weld consistency and quality can be obtained with measurement of the beam size and intensity distribution.

  1. Room temperature Compton profiles of conduction electrons in α-Ga ...

    Indian Academy of Sciences (India)

    Room temperature Compton profiles of momentum distribution of conduction electrons in -Ga metal are calculated in band model. For this purpose, the ... N C Mohapatra2. Department of Physics, Chikiti Mahavidyalaya, Chikiti 761 010, India; Department of Physics, Berhampur University, Berhampur 760 007, India ...

  2. Soft x-ray intensity profile measurements of electron cyclotron heated plasmas using semiconductor detector arrays in GAMMA 10 tandem mirror

    Energy Technology Data Exchange (ETDEWEB)

    Minami, R., E-mail: minami@prc.tsukuba.ac.jp; Imai, T.; Kariya, T.; Numakura, T.; Eguchi, T.; Kawarasaki, R.; Nakazawa, K.; Kato, T.; Sato, F.; Nanzai, H.; Uehara, M.; Endo, Y.; Ichimura, M. [Plasma Research Center, University of Tsukuba, Tsukuba, Ibaraki 305-8577 (Japan)

    2014-11-15

    Temporally and spatially resolved soft x-ray analyses of electron cyclotron heated plasmas are carried out by using semiconductor detector arrays in the GAMMA 10 tandem mirror. The detector array has 16-channel for the measurements of plasma x-ray profiles so as to make x-ray tomographic reconstructions. The characteristics of the detector array make it possible to obtain spatially resolved plasma electron temperatures down to a few tens eV and investigate various magnetohydrodynamic activities. High power electron cyclotron heating experiment for the central-cell region in GAMMA 10 has been started in order to reduce the electron drag by increasing the electron temperature.

  3. Potential beneficial effects of electron-hole plasmas created in silicon sensors by XFEL-like high intensity pulses for detector development

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, Joel T.; Becker, Julian; Shanks, Katherine S.; Philipp, Hugh T.; Tate, Mark W. [Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY 14853 (United States); Gruner, Sol M., E-mail: smg26@cornell.edu [Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY 14853 (United States); Cornell High Energy Synchrotron Source (CHESS), Cornell University, Ithaca, NY 14853 (United States)

    2016-07-27

    There is a compelling need for a high frame rate imaging detector with a wide dynamic range, from single x-rays/pixel/pulse to >10{sup 6} x-rays/pixel/pulse, that is capable of operating at both x-ray free electron laser (XFEL) and 3rd generation sources with sustained fluxes of > 10{sup 11} x-rays/pixel/s [1, 2, 3]. We propose to meet these requirements with the High Dynamic Range Pixel Array Detector (HDR-PAD) by (a) increasing the speed of charge removal strategies [4], (b) increasing integrator range by implementing adaptive gain [5], and (c) exploiting the extended charge collection times of electron-hole pair plasma clouds that form when a sufficiently large number of x-rays are absorbed in a detector sensor in a short period of time [6]. We have developed a measurement platform similar to the one used in [6] to study the effects of high electron-hole densities in silicon sensors using optical lasers to emulate the conditions found at XFELs. Characterizations of the employed tunable wavelength laser with picosecond pulse duration have shown Gaussian focal spots sizes of 6 ± 1 µm rms over the relevant spectrum and 2 to 3 orders of magnitude increase in available intensity compared to previous measurements presented in [6]. Results from measurements on a typical pixelated silicon diode intended for use with the HDR-PAD (150 µm pixel size, 500 µm thick sensor) are presented.

  4. Comparative Study on Extinction Process of Gas-Blasted Air and CO2 Arc Discharge Using Two-Dimensional Electron Density Imaging Sensor

    Science.gov (United States)

    Inada, Yuki; Kamiya, Tomoki; Matsuoka, Shigeyasu; Kumada, Akiko; Ikeda, Hisatoshi; Hidaka, Kunihiko; Nakano, Tomoyuki; Murai, Kosuke; Tanaka, Yasunori; Shinkai, Takeshi

    2015-09-01

    Systematic comparison of the electron density images for various kinds of arc-quenching gas media inside high-voltage circuit breakers is a promising method for the effective search and development of SF6-alternative gases. However, electron density imaging over the decaying arcs around the nozzle throat of the circuit breakers is extremely difficult by using the conventional arc generation setup and localized type sensing systems, due to the nozzle opaqueness and spatiotemporal instability of long-gap arc discharges around current zero. Here, we achieved two-dimensional electron density imaging over the decaying arcs around the nozzle throat first in the world, by a combination of the development of a unique gas flow nozzle integrating a cubic quartz cell and the single-shot recordings using Shack-Hartmann sensors. Shack-Hartmann sensors were applied to gas-blasted air and CO2 arc discharges under current-zero phases after sudden switch-off of stationary arc currents. These experimental results showed that the electron densities and arc diameters took the minimums in the upper stream nozzle regions with the maximum blasting gas speeds. In addition, CO2 had a shorter electron density decaying time constant than air, which is consistent with the previous theoretical studies on higher interruption performance of CO2 compared with air.

  5. Improving electronic customers' profile in recommender systems using data mining techniques

    Directory of Open Access Journals (Sweden)

    Mohammad Julashokri

    2011-10-01

    Full Text Available Recommender systems are tools for realization one to one marketing. Recommender systems are systems, which attract, retain, and develop customers. Recommender systems use several ways to make recommendations. Two ways are using more than the others: collaborative filtering and content-based filtering. In this study, a recommender system model based on collaborative filtering has proposed. Proposed model was endeavored to improve the customer profile in collaborative systems to enhance the recommender system efficiency. This improvement was done using time context and group preferences. Experimental results show that the proposed model has a better recommendation performance than existing models.

  6. A Wire Scanner Design for Electron Beam Profile Measurement in the Linac Coherent Light Source Undulator

    CERN Document Server

    Bailey, James L; Yang Bing Xin

    2005-01-01

    The Linac Coherent Light Source (LCLS), currently under design, requires beam diagnostic instruments between the magnets in the beam undulator section. Ten wire scanners are planned as one of the primary instruments to characterize electron beam properties. The development of these wire scanners presents several design challenges due to the need for high accuracy and resolution of the wire motion (3 microns tolerance, typical) and the high intensity of the beam (3400 A over an area of 30 micron rms radius). In this paper, we present the technical specification and design criteria for the scanners. We will also present the mechanical design of the UHV-compatible drive and its engineering analysis. Lastly, we present the wire card design and discuss associated thermal and mechanical issues originating from the highly intense x-ray and electron beams.

  7. Transmission of electrons in a finite superlattice with a Pascal's Triangle profile

    Science.gov (United States)

    Contreras-Solorio, D. A.; Ortiz, Carlos; Saldaña, X.; López-Cruz, E.

    2005-08-01

    We calculate the electronic transmission coefficient as a function of the incident electron energy in a finite semiconductor superlattice where the width of the barriers is modulated by a numerical sequence taken from the Pascal's Triangle. This sequence is formed by the quantity of odd numbers in each of the Triangles rows and has the pattern 1-2-2-4-2-4-4-8- The sequence has the property of self-similarity. Our superlattice is based in AlAs and GaAs. The transmission spectrum is intermediate between that produced by a periodic finite superlattice and that produced by a disordered one. Moreover the self-similarity of the Pascals structure is reflected in a weak similarity in its transmission spectrum.

  8. X-ray microanalysis with transition edge sensors. The future of material analysis with scanning electron microscopes

    Energy Technology Data Exchange (ETDEWEB)

    Hollerith, C.

    2006-07-05

    In current experiments and technical applications the demand for new and advanced concepts for the detection of radiation and particle is increasing. Low temperature detectors such as Transition Edge Sensors (TES) have been developed as ultrahigh-resolution radiation and particle detectors offering advantages in manifold applications. They were designed primarily for astrophysical experiments such as the dark matter search. In material analysis they have been introduced to revolutionize mass spectroscopy of biological molecules and Energy Dispersive X-ray Spectroscopy (EDS). EDS is the determination of the elemental constitution of samples in scanning electron microscopes (SEMs) with characteristic X-ray radiation excited by the electron beam. The use of TES detectors improves the EDS analysis of small volumes such as particles or thin layers. This is especially important for the semiconductor industry because of the continual shrinking of device size. Current structure sizes of 65 nm are already demanding new approaches in analytic methodology. In this thesis the introduction and improvement of a fully automated TES detector system in the industrial environment of a semiconductor failure analysis lab is described. This system, marketed under the trade name of 'Polaris' by the manufacturer, is based on a mechanical pulse tube cooler in combination with an adiabatic demagnetization refrigerator (ADR) for cooling the TES detector to its operating temperature. Several large improvements had to be made to the system during the total system integration. The energy resolution could be improved significantly thus enabling a better peak separation and the measurement of chemical shifts. Due to the small area of TES detectors compared with conventional EDS detectors the efficiency of the system proved to be too low for everyday use. A polycapillary X-ray lens was added to the system in order to solve this problem. The application of the lens, however, brought its

  9. Vaping’ profiles and preferences: an online survey of electronic cigarette users

    OpenAIRE

    Dawkins, Lynne

    2013-01-01

    Aims to characterize e-cigarette use, users, and effects, in a sample of Electronic Cigarette Company (TECC) and Totally Wicked E-Liquid (TWEL) users. Design and Setting Online survey hosted at the University of East London with links from TECC/TWEL websites between September 2011 to May 2012. Measurements Online questionnaire. Participants 1347 respondents from 33 countries (72% European), mean age 43 years, 70% male, 96% Causacian, 44% educated to degree level or above. Findings 74% reporte...

  10. Correlated magnetic impurities in a superconductor: electron density profiles and robustness of superconductivity.

    Science.gov (United States)

    Sacramento, P D; Dugaev, V K; Vieira, V R; Araújo, M A N

    2010-01-20

    The insertion of magnetic impurities in a conventional superconductor leads to various effects. In this work we show that the electron density is affected by the spins (considered as classical) both locally and globally. The charge accumulation is solved self-consistently. This affects the transport properties along magnetic domain walls. Also, we show that superconductivity is more robust if the spin locations are not random but correlated. © 2010 IOP Publishing Ltd

  11. Improving the Automatic Inversion of Digital Alouette/ISIS Ionogram Reflection Traces into Topside Electron Density Profiles

    Science.gov (United States)

    Benson, Robert F.; Truhlik, Vladimir; Huang, Xueqin; Wang, Yongli; Bilitza, Dieter

    2012-01-01

    The topside sounders of the International Satellites for Ionospheric Studies (ISIS) program were designed as analog systems. The resulting ionograms were displayed on 35 mm film for analysis by visual inspection. Each of these satellites, launched between 1962 and 1971, produced data for 10 to 20 years. A number of the original telemetry tapes from this large data set have been converted directly into digital records. Software, known as the Topside Ionogram Scalar With True-Height (TOPIST) algorithm, has been produced and used for the automatic inversion of the ionogram reflection traces on more than 100,000 ISIS-2 digital topside ionograms into topside vertical electron density profiles Ne(h). Here we present some topside ionospheric solar cycle variations deduced from the TOPIST database to illustrate the scientific benefit of improving and expanding the topside ionospheric Ne(h) database. The profile improvements will be based on improvements in the TOPIST software motivated by direct comparisons between TOPIST profiles and profiles produced by manual scaling in the early days of the ISIS program. The database expansion will be based on new software designed to overcome limitations in the original digital topside ionogram database caused by difficulties encountered during the analog-to-digital conversion process in the detection of the ionogram frame sync pulse and/or the frequency markers. This improved and expanded TOPIST topside Ne(h) database will greatly enhance investigations into both short- and long-term ionospheric changes, e.g., the observed topside ionospheric responses to magnetic storms, induced by interplanetary magnetic clouds, and solar cycle variations, respectively.

  12. Global proteomic profiling of phosphopeptides using electron transfer dissociation tandem mass spectrometry

    DEFF Research Database (Denmark)

    Molina, Henrik; Horn, David M; Tang, Ning

    2007-01-01

    Electron transfer dissociation (ETD) is a recently introduced mass spectrometric technique that provides a more comprehensive coverage of peptide sequences and posttranslational modifications. Here, we evaluated the use of ETD for a global phosphoproteome analysis. In all, we identified a total...... of 1,435 phosphorylation sites from human embryonic kidney 293T cells, of which 1,141 ( approximately 80%) were not previously described. A detailed comparison of ETD and collision-induced dissociation (CID) modes showed that ETD identified 60% more phosphopeptides than CID, with an average of 40% more...

  13. Mission profile emulator for the power electronics systems of motor drive applications

    DEFF Research Database (Denmark)

    Vernica, Ionut; Blaabjerg, Frede; Ma, Ke

    2017-01-01

    Due to the adverse temperature swings which normally occur in the power semiconductor devices during the start-up and deceleration periods of the motor drive system, the thermal design and control, as well as the reliability analysis of the power devices becomes crucial. In order to facilitate...... testing and access the loading and lifetime performances, a novel stress emulator for power semiconductor devices based on the mission profile of a motor drive system is proposed and designed. The control algorithm for the stress emulator setup is introduced, and the issues concerning the Orthogonal...... Signal Generator (OSG) are addressed by means of adaptive Notch filter implementation. Finally, experimental results are provided in order to validate the effectiveness of the proposed emulation technique....

  14. Gene and protein expression profiles of Shewanella oneidensis during anaerobic growth with different electron acceptors.

    Energy Technology Data Exchange (ETDEWEB)

    Beliaev, A. S.; Thompson, D. K.; Khare, T.; Lim, H.; Brandt, C. C.; Li, G.; Murray, A. E.; Heidelberg, J. F.; Giometti, C. S.; Yates, J., III; Nealson, K. H.; Tiedje, J. M.; Zhou, J.; Biosciences Division; ORNL; Scripps Research Inst.; Michigan State Univ.; The Inst. for Genomic Research; Jet Propulsion Laboratory; California Inst. of Tech.

    2002-01-01

    Changes in mRNA and protein expression profiles of Shewanella oneidenesis MR-1 during switch from aerobic to fumarate-, Fe(III)-, or nitrate-reducing conditions were examined using DNA microarrays and two-dimensional polyacrylamide gel electrophoresis (2-D PAGE). In response to changes in growth conditions, 121 of the 691 arrayed genes displayed at least a two-fold difference in transcript abundance as determined by microarray analysis. Genes involved in aerobic respiration encoding cytochrome c and d oxidases and TCA cycle enzymes were repressed under anaerobic conditions. Genes induced during anaerobic respiration included those involved in cofactor biosynthesis and assembly (moaACE, ccmHF, nosD, cysG), substrate transport (cysUP, cysTWA, dcuB), and anaerobic energy metabolism (dmsAB, psrC, pshA, hyaABC, hydA). Transcription of genes encoding a periplasmic nitrate reductase (napBHGA), cytochrome c{sub 552}, and prismane was elevated 8- to 56-fold in response to the presence of nitrate, while cymA, ifcA, and frdA were specifically induced three- to eightfold under fumarate-reducing conditions. The mRNA levels for two oxidoreductase-like genes of unknown function and several cell envelope genes involved in multidrug resistance increased two- to fivefold specifically under Fe(III)-reducing conditions. Analysis of protein expression profiles under aerobic and anaerobic conditions revealed 14 protein spots that showed significant differences in abundance on 2-D gels. Protein identification by mass spectrometry indicated that the expression of prismane, dihydrolipoamide succinyltransferase, and alcaligin siderophore biosynthesis protein correlated with the microarray data.

  15. A Wireless Sensor System for Real-Time Measurement of Pressure Profiles at Lower Limb Protheses to Ensure Proper Fitting

    Science.gov (United States)

    2011-10-01

    sensor response. Microcontroller Program: To maintain versatility in design, the MSP430 code was l imited to a proportional plus integ ral...controller that c ould receive commands from a ma ster central processing unit (CPU), via standard RS-232 communication implemented on the MSP430 ’ s UART...connected to onboard ADC pins. A custom SPI protocol wa s written to provide necessary setup and transition times as the MSP430 peripheral interface was

  16. Cryogenic-temperature profiling of high-power superconducting lines using local and distributed optical-fiber sensors

    OpenAIRE

    Chiuchiolo, Antonella; Palmieri, Luca; Consales, Marco; Giordano, Michele; Borriello, Anna; Bajas, Hugues; Galtarossa, Andrea; Bajko, Marta; Cusano, Andrea

    2015-01-01

    This contribution presents distributed and multi-point fiber-optic monitoring of cryogenic temperatures along a superconducting power transmission line down to 30 K and over 20 m distance. Multi-point measurements were conducted using fiber Bragg gratings sensors coated with two different functional overlays (epoxy and PMMA) demonstrating cryogenic operation in the range 300 – 4.2 K. Distributed measurements exploited optical frequency-domain reflectometry to analyze the Rayleigh scattering a...

  17. Disorder profile of nebulin encodes a vernierlike position sensor for the sliding thin and thick filaments of the skeletal muscle sarcomere

    Science.gov (United States)

    Wu, Ming-Chya; Forbes, Jeffrey G.; Wang, Kuan

    2016-06-01

    Nebulin is an about 1 μ m long intrinsically disordered scaffold for the thin filaments of skeletal muscle sarcomere. It is a multifunctional elastic protein that wraps around actin filament, stabilizes thin filaments, and regulates Ca-dependent actomyosin interactions. This study investigates whether the disorder profile of nebulin might encode guidelines for thin and thick filament interactions in the sarcomere of the skeletal muscle. The question was addressed computationally by analyzing the predicted disorder profile of human nebulin (6669 residues, ˜200 actin-binding repeats) by pondr and the periodicity of the A-band stripes (reflecting the locations of myosin-associated proteins) in the electron micrographs of the sarcomere. Using the detrended fluctuation analysis, a scale factor for the A-band stripe image data with respect to the nebulin disorder profile was determined to make the thin and thick filaments aligned to have maximum correlation. The empirical mode decomposition method was then applied to identify hidden periodicities in both the nebulin disorder profile and the rescaled A-band data. The decomposition reveals three characteristic length scales (45 nm, 100 nm, and 200 nm) that are relevant for correlational analysis. The dynamical cross-correlation analyses with moving windows at various sarcomere lengths depict a vernierlike design for both periodicities, thus enabling nebulin to sense position and fine tune sarcomere overlap. This shows that the disorder profile of scaffolding proteins may encode a guideline for cellular architecture.

  18. Electronic structure computation and differential capacitance profile in δ-doped FET as a function of hydrostatic pressure

    Energy Technology Data Exchange (ETDEWEB)

    Carlos-Pinedo, C.; Rodríguez-Vargas, I.; Martínez-Orozco, J. C. [Unidad Académica de Física. Universidad Autónoma de Zacatecas. Calzada Solidaridad Esquina con Paseo la Bufa S/N. C.P. 98060, Zacatecas, Zac. (Mexico)

    2014-05-15

    In this work we present the results obtained from the calculation of the level structure of a n-type delta-doped well Field Effect Transistor when is subjected to hydrostatic pressure. We study the energy level structure as a function of hydrostatic pressure within the range of 0 to 6 kbar for different Schottky barrier height (SBH). We use an analytical expression for the effect of hydrostatic pressure on the SBH and the pressure dependence of the basic parameters of the system as the effective mass m(P) and the dielectric constant ε(P) of GaAs. We found that due to the effects of hydrostatic pressure, in addition to electronic level structure alteration, the profile of the differential capacitance per unit area C{sup −2} is affected.

  19. How gamma and electron-beam irradiations modulate phenolic profile expression in Melissa officinalis L. and Melittis melissophyllum L.

    Science.gov (United States)

    Pereira, Eliana; Antonio, Amilcar; Barreira, João C M; Santos-Buelga, Celestino; Barros, Lillian; Ferreira, Isabel C F R

    2018-02-01

    Owing to the overall increase in herbal infusions' consumption, there's a progressively higher need of suitable plant material, as well as adequate conservation techniques to maintain its quality. Among, the available technologies, irradiation is gaining interest as a feasible preservation method. In line with this approach, this wok was designed to evaluate the effects of electron-beam and gamma irradiation over the phenolic profiles of two plant species Melissa officinalis L. (LB) and Melittis melissophyllum L. (BB). Individual phenolics were characterized by high-performance liquid chromatography coupled to a diode array detector and a mass spectrometer (HPLC-DAD-ESI/MS). Irradiated samples showed a general increase in individual phenolic contents, especially in lithospermic acid A in LB and 5-O-caffeoylquinic acid in BB. Thus, this study revealed the potential usefulness of both conservation technologies when employed to this type of plants. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Identifying the 630 nm auroral arc emission height: A comparison of the triangulation, FAC profile, and electron density methods

    Science.gov (United States)

    Megan Gillies, D.; Knudsen, D.; Donovan, E.; Jackel, B.; Gillies, R.; Spanswick, E.

    2017-08-01

    We present a comprehensive survey of 630 nm (red-line) emission discrete auroral arcs using the newly deployed Redline Emission Geospace Observatory. In this study we discuss the need for observations of 630 nm aurora and issues with the large-altitude range of the red-line aurora. We compare field-aligned currents (FACs) measured by the Swarm constellation of satellites with the location of 10 red-line (630 nm) auroral arcs observed by all-sky imagers (ASIs) and find that a characteristic emission height of 200 km applied to the ASI maps gives optimal agreement between the two observations. We also compare the new FAC method against the traditional triangulation method using pairs of all-sky imagers (ASIs), and against electron density profiles obtained from the Resolute Bay Incoherent Scatter Radar-Canadian radar, both of which are consistent with a characteristic emission height of 200 km.

  1. Integrated inertial sensors and mobile computing for real-time cycling performance guidance via pedaling profile classification.

    Science.gov (United States)

    Xu, James Y; Nan, Xiaomeng; Ebken, Victor; Wang, Yan; Pottie, Greg J; Kaiser, William J

    2015-03-01

    Today, the bicycle is utilized as a daily commute tool, a physical rehabilitation asset, and sporting equipment, prompting studies into the biomechanics of cycling. Of the number of important parameters that affect cycling efficiency, the foot angle profile is one of the most important as it correlates directly with the effective force applied to the bike. However, there has been no compact and portable solution for measuring the foot angle and for providing the cyclist with real-time feedback due to a number of difficulties of the current tracking and sensing technologies and the myriad types of bikes available. This paper presents a novel sensing and mobile computing system for classifying the foot angle profiles during cycling and for providing real-time guidance to the user to achieve the correct profile. Continuous foot angle tracking is firstly converted into a discrete problem requiring only recognition of acceleration profiles of the foot using a single shoe mounted tri-axial accelerometer during each pedaling cycle. A classification method is then applied to identify the pedaling profile. Finally, a mobile solution is presented to provide real-time signal processing and guidance.

  2. Voltage profile, structural prediction, and electronic calculations for MgxMo6S8

    CSIR Research Space (South Africa)

    Kganyago, KR

    2003-03-01

    Full Text Available suggests a maximum uptake formally of two Mg ions into the electron-de?cient Mo6 cluster, which leaves us with two possible vacant sites: the inner Li1 site ~substituted by MgA) close to the unit-cell origin with the atom coordinates (0.598,0.359,0.381:b52... be de?ned with Mg0 being the origin. The vector from Mg0 to Mg1 is the c lattice parameter and the vectors from Mg0 to Mg2 and Mg0 to Mg3 are the a lattice parameters. K. R. KGANYAGO, P. E. NGOEPE, AND C. R. A. CATLOW PHYSICAL REVIEW B 67, 104103 ~2003...

  3. Modeling of temperature profiles in an environmental transmission electron microscope using computational fluid dynamics

    DEFF Research Database (Denmark)

    Mortensen, Peter Mølgaard; Jensen, Anker Degn; Hansen, Thomas Willum

    2015-01-01

    The temperature and velocity field, pressure distribution, and the temperature variation across the sample region inside an environmental transmission electron microscope (ETEM) have been modeled by means of computational fluid dynamics (CFD). Heating the sample area by a furnace type TEM holder ...... difference over the TEM grid is less than 5. °C, at what must be considered typical conditions, and it is concluded that the conditions on the sample grid in the ETEM can be considered as isothermal during general use....... gives rise to temperature gradients over the sample area. Three major mechanisms have been identified with respect to heat transfer in the sample area: radiation from the grid, conduction in the grid, and conduction in the gas. A parameter sensitivity analysis showed that the sample temperature...

  4. Dual-MWCNT Probe Thermal Sensor Assembly and Evaluation Based on Nanorobotic Manipulation inside a Field-Emission-Scanning Electron Microscope

    Directory of Open Access Journals (Sweden)

    Zhan Yang

    2015-03-01

    Full Text Available We report a thermal sensor composed of two multiwalled carbon nano-tubes (MWCNTs inside a field-emission-scanning electron microscope. The sensor was assembled using a nanorobotic manipulation system, which was used to construct a probe tip in order to detect the local environment of a single cell. An atomic force microscopy (AFM cantilever was used as a substrate; the cantilever was composed of Si3N4 and both sides were covered with a gold layer. MWCNTs were individually assembled on both sides of the AFM cantilever by employing nanorobotic manipulation. Another AFM cantilever was subsequently used as an end effector to manipulate the MWCNTs to touch each other. Electron-beam-induced deposition (EBID was then used to bond the two MWCNTs. The MWCNT probe thermal sensor was evaluated inside a thermostated container in the temperature range from 25°C to 60°C. The experimental results show the positive characteristics of the temperature coefficient of resistance (TCR.

  5. Preparation, characterization, and application of Pd-SnO sensors as an electronic nose in Peruvian wine classification and its comparison with chromatographic techniques

    Directory of Open Access Journals (Sweden)

    Ana Lucía Paredes Doig

    2018-01-01

    Full Text Available SnO-based  sensors  doped  with  palladium (0,  1,  3,  5  and  7%  were  prepared  by the wet impregnation method. To characterize them, the techniques of infrared spectroscopy with Fourier transform (FTIR, adsorption and desorption of N2 (BET, XRD, scanning electron microscopy (SEM, and X-ray dispersive  energy  (EDX  spectroscopy were used. The sensors  were  evaluated with ethanol  to form, together with two commercial sensors, an electronic nose (E-nose that could detect volatile aroma components  in  Peruvian wines.  The  results were interpreted through principal component analysis (PCA to find a technique that complemented the information collected by gas chromatography (GC and liquid chromatography (HPLC, and by comparing the PCAs obtained from GC and HPLC with those resulting from E-nose. It was found that the latter classified the samples better. It was possible to differentiate both wines from the same  grape  and  from  a  different strain, and to detect adulterated wines, which contributes to the wine industry in controlling its production to improve the quality of this drink for the consumer.

  6. Spatially Resolved Spectra from a new X-ray Imaging Crystal Spectrometer for Measurements of Ion and Electron Temperature Profiles

    Energy Technology Data Exchange (ETDEWEB)

    Bitter, M; Stratton, B; Roquemore, A; Mastrovito, D; Lee, S; Bak, J; Moon, M; Nam, U; Smith, G; Rice, J; Beiersdorfer, P; Fraenkel, B

    2004-08-10

    A new type of high-resolution X-ray imaging crystal spectrometer is being developed to measure ion and electron temperature profiles in tokamak plasmas. The instrument is particularly valuable for diagnosing plasmas with purely Ohmic heating and rf heating, since it does not require the injection of a neutral beam - although it can also be used for the diagnosis of neutral-beam heated plasmas. The spectrometer consists of a spherically bent quartz crystal and a two-dimensional position-sensitive detector. It records spectra of helium-like argon (or krypton) from multiple sightlines through the plasma and projects a de-magnified image of a large plasma cross-section onto the detector. The spatial resolution in the plasma is solely determined by the height of the crystal, its radius of curvature, and the Bragg angle. This new X-ray imaging crystal spectrometer may also be of interest for the diagnosis of ion temperature profiles in future large tokamaks, such as KSTAR and ITER, where the application of the presently used charge-exchange spectroscopy will be difficult, if the neutral beams do not penetrate to the plasma center. The paper presents the results from proof-of-principle experiments performed with a prototype instrument at Alcator C-Mod.

  7. Improving the Automatic Inversion of Digital ISIS-2 Ionogram Reflection Traces into Topside Vertical Electron-Density Profiles

    Science.gov (United States)

    Benson, R. F.; Truhlik, V.; Huang, X.; Wang, Y.; Bilitza, D.

    2011-01-01

    The topside-sounders on the four satellites of the International Satellites for Ionospheric Studies (ISIS) program were designed as analog systems. The resulting ionograms were displayed on 35-mm film for analysis by visual inspection. Each of these satellites, launched between 1962 and 1971, produced data for 10 to 20 years. A number of the original telemetry tapes from this large data set have been converted directly into digital records. Software, known as the TOPside Ionogram Scalar with True-height (TOPIST) algorithm has been produced that enables the automatic inversion of ISIS-2 ionogram reflection traces into topside vertical electron-density profiles Ne(h). More than million digital Alouette/ISIS topside ionograms have been produced and over 300,000 are from ISIS 2. Many of these ISIS-2 ionograms correspond to a passive mode of operation for the detection of natural radio emissions and thus do not contain ionospheric reflection traces. TOPIST, however, is not able to produce Ne(h) profiles from all of the ISIS-2 ionograms with reflection traces because some of them did not contain frequency information. This information was missing due to difficulties encountered during the analog-to-digital conversion process in the detection of the ionogram frame-sync pulse and/or the frequency markers. Of the many digital topside ionograms that TOPIST was able to process, over 200 were found where direct comparisons could be made with Ne(h) profiles that were produced by manual scaling in the early days of the ISIS program. While many of these comparisons indicated excellent agreement (inversion process: (1) improve the quality of the digital ionogram database by remedying the missing frequency-information problem when possible, and (2) using the above-mentioned comparisons as teaching examples of how to improve the original TOPIST software.

  8. Comparative study on extinction process of gas-blasted air and CO2 arc discharge using two-dimensional electron density imaging sensor

    Science.gov (United States)

    Inada, Yuki; Kumada, Akiko; Ikeda, Hisatoshi; Hidaka, Kunihiko; Nakano, Tomoyuki; Murai, Kosuke; Tanaka, Yasunori; Shinkai, Takeshi

    2017-05-01

    Shack-Hartmann type laser wavefront sensors were applied to gas-blasted arc discharges under current-zero phases, generated in a 50 mm-long interelectrode gap confined by a gas flow nozzle, in order to conduct a systematic comparison of electron density decaying processes for two kinds of arc-quenching gas media: air and \\text{C}{{\\text{O}}2} . The experimental results for the air and \\text{C}{{\\text{O}}2} arc plasmas showed that the electron densities and arc diameters became thinner toward the nozzle-throat inlet due to a stronger convection loss in the arc radial direction. In addition, \\text{C}{{\\text{O}}2} had a shorter electron density decaying time constant than air, which could be caused by convection loss and turbulent flow of \\text{C}{{\\text{O}}2} stronger than air.

  9. In Vitro Dosing Performance of the ELLIPTA? Dry Powder Inhaler Using Asthma and COPD Patient Inhalation Profiles Replicated with the Electronic Lung (eLung?)

    OpenAIRE

    Hamilton, Melanie; Leggett, Richard; Pang, Cheng; Charles, Stephen; Gillett, Ben; Prime, David

    2015-01-01

    Abstract Background: To evaluate the in vitro dose delivery characteristics of approved asthma and chronic obstructive pulmonary disease (COPD) therapies delivered via the ELLIPTA? dry powder inhaler across inhalation endpoints representative of the target patient population, using the Electronic Lung (eLung?) to replicate inhaler-specific patient inhalation profiles that were previously recorded in vivo. Methods: Selected profiles, representative of the range of inhalation endpoints achieved...

  10. Guideline-driven telemonitoring and follow-up of cardiovascular implantable electronic devices using IEEE 11073, HL7 & IHE profiles.

    Science.gov (United States)

    Yang, Maohua; Chronaki, Catherine E; Lüpkes, Christian; Thiel, Andreas; Plössnig, Manuela; Hinterbuchner, Lynne; Arbelo, Elena; Laleci, Gokce Banu; Kabak, Yildiray; Duarte, Fernandez; Guillén, Alejandra; Navarro, Xavier; Dogac, Asuman; Eichelberg, Marco; Hein, Andreas

    2011-01-01

    For patients with Cardiovascular Implantable Electronic Devices (CIEDs), telemonitoring promises improved quality of life and safety, since events recorded by the device or observed by the patient can alert a health professional. Taking into account the latest clinical guidelines when responding to such alerts, is a topic of active research addressed by the iCARDEA project. A key technical challenge is correlating telemonitoring CIED report data in a vendor-independent format with Electronic Health Record (EHR) data collected in the hospital and Personal Health Record (PHR) data entered by the patient, in guideline-driven care processes. The iCARDEA CIED exposure service component presented in this paper employs standards specifications from ISO/IEEE 11073 (Health Informatics, Point-of-care Medical Device Communication) and HL7v2.x in the context of Integrating the Healthcare Enterprise (IHE) profiles to deliver telemonitoring CIED report data from two different CIED vendors to the adaptive care planner that implements guideline-driven care plans. Experience gained with implementation and initial component testing is discussed, while challenges and expectations for future health information standards to effectively support EHR-integrated guide-line-driven telemonitoring services are highlighted.

  11. Modeling of temperature profiles in an environmental transmission electron microscope using computational fluid dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Mølgaard Mortensen, Peter [Department of Chemical and Biochemical Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby (Denmark); Willum Hansen, Thomas [Center for Electron Nanoscopy, Technical University of Denmark, DK-2800 Kgs. Lyngby (Denmark); Birkedal Wagner, Jakob, E-mail: jakob.wagner@cen.dtu.dk [Center for Electron Nanoscopy, Technical University of Denmark, DK-2800 Kgs. Lyngby (Denmark); Degn Jensen, Anker, E-mail: aj@kt.dtu.dk [Department of Chemical and Biochemical Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby (Denmark)

    2015-05-15

    The temperature and velocity field, pressure distribution, and the temperature variation across the sample region inside an environmental transmission electron microscope (ETEM) have been modeled by means of computational fluid dynamics (CFD). Heating the sample area by a furnace type TEM holder gives rise to temperature gradients over the sample area. Three major mechanisms have been identified with respect to heat transfer in the sample area: radiation from the grid, conduction in the grid, and conduction in the gas. A parameter sensitivity analysis showed that the sample temperature was affected by the conductivity of the gas, the emissivity of the sample grid, and the conductivity of the grid. Ideally the grid should be polished and made from a material with good conductivity, e.g. copper. With hydrogen gas, which has the highest conductivity of the gases studied, the temperature difference over the TEM grid is less than 5 °C, at what must be considered typical conditions, and it is concluded that the conditions on the sample grid in the ETEM can be considered as isothermal during general use. - Highlights: • Computational fluid dynamics used for mapping flow and temperature in ETEM setup. • Temperature gradient across TEM grid in furnace based heating holder very small in ETEM. • Conduction from TEM grid and gas in addition to radiation from TEM grid most important. • Pressure drop in ETEM limited to the pressure limiting apertures.

  12. Assessment of a Standardized ROS Production Profile in Humans by Electron Paramagnetic Resonance

    Directory of Open Access Journals (Sweden)

    Simona Mrakic-Sposta

    2012-01-01

    Full Text Available Despite the growing interest in the role of reactive oxygen species (ROS in health and disease, reliable quantitative noninvasive methods for the assessment of oxidative stress in humans are still lacking. EPR technique, coupled to a specific spin probe (CMH: 1-hydroxy-3-methoxycarbonyl-2,2,5,5-tetramethylpyrrolidine is here presented as the method of choice to gain a direct measurement of ROS in biological fluids and tissues. The study aimed at demonstrating that, differently from currently available “a posteriori” assays of ROS-induced damage by means of biomolecules (e.g., proteins and lipids spin-trapping EPR provides direct evidence of the “instantaneous” presence of radical species in the sample and, as signal areas are proportional to the number of excited electron spins, lead to absolute concentration levels. Using a recently developed bench top continuous wave system (e-scan EPR scanner, Bruker dealing with very low ROS concentration levels in small (50 μL samples, we successfully monitored rapid ROS production changes in peripheral blood of athletes after controlled exercise and sedentary subjects after antioxidant supplementation. The correlation between EPR results and data obtained by various enzymatic assays (e.g., protein carbonyls and thiobarbituric acid reactive substances was determined too. Synthetically, our method allows reliable, quick, noninvasive quantitative determination of ROS in human peripheral blood.

  13. Practical procedure for discriminating monofloral honey with a broad pollen profile variability using an electronic tongue.

    Science.gov (United States)

    Sousa, Mara E B C; Dias, Luís G; Veloso, Ana C A; Estevinho, Letícia; Peres, António M; Machado, Adélio A S C

    2014-10-01

    Colour and floral origin are key parameters that may influence the honey market. Monofloral light honey are more demanded by consumers, mainly due to their flavour, being more valuable for producers due to their higher price when compared to darker honey. The latter usually have a high anti-oxidant content that increases their healthy potential. This work showed that it is possible to correctly classify monofloral honey with a high variability in floral origin with a potentiometric electronic tongue after making a preliminary selection of honey according their colours: white, amber and dark honey. The results showed that the device had a very satisfactory sensitivity towards floral origin (Castanea sp., Echium sp., Erica sp., Lavandula sp., Prunus sp. and Rubus sp.), allowing a leave-one-out cross validation correct classification of 100%. Therefore, the E-tongue shows potential to be used at analytical laboratory level for honey samples classification according to market and quality parameters, as a practical tool for ensuring monofloral honey authenticity. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Distributed Optical Fiber Sensors with Ultrafast Laser Enhanced Rayleigh Backscattering Profiles for Real-Time Monitoring of Solid Oxide Fuel Cell Operations.

    Science.gov (United States)

    Yan, Aidong; Huang, Sheng; Li, Shuo; Chen, Rongzhang; Ohodnicki, Paul; Buric, Michael; Lee, Shiwoo; Li, Ming-Jun; Chen, Kevin P

    2017-08-24

    This paper reports a technique to enhance the magnitude and high-temperature stability of Rayleigh back-scattering signals in silica fibers for distributed sensing applications. With femtosecond laser radiation, more than 40-dB enhancement of Rayleigh backscattering signal was generated in silica fibers using 300-nJ laser pulses at 250 kHz repetition rate. The laser-induced Rayleigh scattering defects were found to be stable from the room temperature to 800 °C in hydrogen gas. The Rayleigh scatter at high temperatures was correlated to the formation and modification of nanogratings in the fiber core. Using optical fibers with enhanced Rayleigh backscattering profiles as distributed temperature sensors, we demonstrated real-time monitoring of solid oxide fuel cell (SOFC) operations with 5-mm spatial resolution at 800 °C. Information gathered by these fiber sensor tools can be used to verify simulation results or operated in a process-control system to improve the operational efficiency and longevity of SOFC-based energy generation systems.

  15. 'Vaping' profiles and preferences: an online survey of electronic cigarette users.

    Science.gov (United States)

    Dawkins, Lynne; Turner, John; Roberts, Amanda; Soar, Kirstie

    2013-06-01

    To characterize e-cigarette use, users and effects in a sample of Electronic Cigarette Company (TECC) and Totally Wicked E-Liquid (TWEL) users. Online survey hosted at the University of East London with links from TECC/TWEL websites from September 2011 to May 2012. Online questionnaire. One thousand three hundred and forty-seven respondents from 33 countries (72% European), mean age 43 years, 70% male, 96% Causasian, 44% educated to degree level or above. Seventy-four percent of participants reported not smoking for at least a few weeks since using the e-cigarette and 70% reported reduced urge to smoke. Seventy-two percent of participants used a 'tank' system, most commonly, the eGo-C (23%). Mean duration of use was 10 months. Only 1% reported exclusive use of non-nicotine (0 mg) containing liquid. E-cigarettes were generally considered to be satisfying to use; elicit few side effects; be healthier than smoking; improve cough/breathing; and be associated with low levels of craving. Among ex-smokers, 'time to first vape' was significantly longer than 'time to first cigarette' (t1104  = 11.16, P e-cigarettes. Ex-smokers reported significantly greater reduction in craving than current smokers (χ(2) 1  = 133.66, P cigarette because it resembles a cigarette (χ(2) 3  = 42.65, P E-cigarettes are used primarily for smoking cessation, but for a longer duration than nicotine replacement therapy, and users believe them to be safer than smoking. © 2013 Society for the Study of Addiction.

  16. Study of reversible electrode reaction and mixed ionic and electronic conduction of lithium phosphate electrolyte for an electrochemical CO2 gas sensor

    Science.gov (United States)

    Lee, Chong-Hoon

    An electrochemical CO2 gas sensor with lithium ion conductor was developed and characterized in order to examine the potential for real-life applications and understand its sensing mechanism. Li2CO3 and Li2TiO3 + TiO2 mixture were used as a sensing and a reference auxiliary phase, respectively. This electrochemical cell with a solid state Li3PO4 electrolyte has shown good selectivity, sensitivity and linear response in laboratory and automobile exhaust tests. However, the sensor response to CO2 gas showed a systematic deviation from the Nernst equation. Measured EMF did not agree with that calculated from the Nernst equation, even though it followed logarithmic behavior. Moreover, high sensitivity was observed for high CO2 concentrations (5˜50%), compared to that for concentrations (500˜5000 ppm). Two possible reasons for this deviation are: (1) reversibility of electrode reaction and (2) mixed ionic and electronic conduction of the electrolyte. Unless electrode reaction is fast enough, electrode polarization can easily induce overpotential. Pure ionic conduction of electrolyte is also necessary to avoid EMF loss during open circuit potential measurement. EIS (Electrochemical Impedance Spectroscopy) was used to study electrode kinetics. We found that Li2TiO3 + TiO2 mixture reference electrode reaction is sluggish showing large electrode impedance. This impedance, however, was not affected by gas concentration change. On the other hand, that at the Li2CO3 sensing electrode is relatively small and it increased with decreased CO2 and O 2 concentration. It was also observed that these electrode impedances induced the overpotential when the current flowed through the sensor. This electrode overpotential problem was minimized by mixing gold powder or porous sputtered gold electrode increasing effective reaction sites of the electrode. New electrode design improved the sensor EMF closer to the Nernstian values, however, the discrepancy still remained. Moreover, at

  17. Applying Sensor Web Technology to Marine Sensor Data

    Science.gov (United States)

    Jirka, Simon; del Rio, Joaquin; Mihai Toma, Daniel; Nüst, Daniel; Stasch, Christoph; Delory, Eric

    2015-04-01

    In this contribution we present two activities illustrating how Sensor Web technology helps to enable a flexible and interoperable sharing of marine observation data based on standards. An important foundation is the Sensor Web Architecture developed by the European FP7 project NeXOS (Next generation Low-Cost Multifunctional Web Enabled Ocean Sensor Systems Empowering Marine, Maritime and Fisheries Management). This architecture relies on the Open Geospatial Consortium's (OGC) Sensor Web Enablement (SWE) framework. It is an exemplary solution for facilitating the interoperable exchange of marine observation data within and between (research) organisations. The architecture addresses a series of functional and non-functional requirements which are fulfilled through different types of OGC SWE components. The diverse functionalities offered by the NeXOS Sensor Web architecture are shown in the following overview: - Pull-based observation data download: This is achieved through the OGC Sensor Observation Service (SOS) 2.0 interface standard. - Push-based delivery of observation data to allow users the subscription to new measurements that are relevant for them: For this purpose there are currently several specification activities under evaluation (e.g. OGC Sensor Event Service, OGC Publish/Subscribe Standards Working Group). - (Web-based) visualisation of marine observation data: Implemented through SOS client applications. - Configuration and controlling of sensor devices: This is ensured through the OGC Sensor Planning Service 2.0 interface. - Bridging between sensors/data loggers and Sensor Web components: For this purpose several components such as the "Smart Electronic Interface for Sensor Interoperability" (SEISI) concept are developed; this is complemented by a more lightweight SOS extension (e.g. based on the W3C Efficient XML Interchange (EXI) format). To further advance this architecture, there is on-going work to develop dedicated profiles of selected OGC

  18. Towards point of care testing for C. difficile infection by volatile profiling, using the combination of a short multi-capillary gas chromatography column with metal oxide sensor detection.

    Science.gov (United States)

    McGuire, N D; Ewen, R J; de Lacy Costello, B; Garner, C E; Probert, C S J; Vaughan, K; Ratcliffe, N M

    2014-05-12

    Rapid volatile profiling of stool sample headspace was achieved using a combination of short multi-capillary chromatography column (SMCC), highly sensitive heated metal oxide semiconductor (MOS) sensor and artificial neural network (ANN) software. For direct analysis of biological samples this prototype offers alternatives to conventional GC detectors and electronic nose technology. The performance was compared to an identical instrument incorporating a long single capillary column (LSCC). The ability of the prototypes to separate complex mixtures was assessed using gas standards and homogenised in house 'standard' stool samples, with both capable of detecting more than 24 peaks per sample. The elution time was considerably faster with the SMCC resulting in a run time of 10 minutes compared to 30 minutes for the LSCC. The diagnostic potential of the prototypes was assessed using 50 C. difficile positive and 50 negative samples. The prototypes demonstrated similar capability of discriminating between positive and negative samples with sensitivity and specificity of 85% and 80% respectively. C. difficile is an important cause of hospital acquired diarrhoea, with significant morbidity and mortality around the world. A device capable of rapidly diagnosing the disease at the point of care would reduce cases, deaths and financial burden.

  19. Polar observations of electron density distribution in the Earth’s magnetosphere. 2. Density profiles

    Directory of Open Access Journals (Sweden)

    H. Laakso

    Full Text Available Using spacecraft potential measurements of the Polar electric field experiment, we investigate electron density variations of key plasma regions within the magnetosphere, including the polar cap, cusp, trough, plasmapause, and auroral zone. The statistical results were presented in the first part of this study, and the present paper reports detailed structures revealed by individual satellite passes. The high-altitude (> 3 RE polar cap is generally one of the most tenuous regions in the magnetosphere, but surprisingly, the polar cap boundary does not appear as a steep density decline. At low altitudes (1 RE in summer, the polar densities are very high, several 100 cm-3 , and interestingly, the density peaks at the central polar cap. On the noonside of the polar cap, the cusp appears as a dense, 1–3° wide region. A typical cusp density above 4 RE distance is between several 10 cm-3 and a few 100 cm-3 . On some occasions the cusp is crossed multiple times in a single pass, simultaneously with the occurrence of IMF excursions, as the cusp can instantly shift its position under varying solar wind conditions, similar to the magnetopause. On the nightside, the auroral zone is not always detected as a simple density cavity. Cavities are observed but their locations, strengths, and sizes vary. Also, the electric field perturbations do not necessarily overlap with the cavities: there are cavities with no field disturbances, as well as electric field disturbances observed with no clear cavitation. In the inner magnetosphere, the density distributions clearly show that the plasmapause and trough densities are well correlated with geomagnetic activity. Data from individual orbits near noon and midnight demonstrate that at the beginning of geomagnetic disturbances, the retreat speed of the plasmapause can be one L-shell per hour, while during quiet intervals the

  20. Polar observations of electron density distribution in the Earth’s magnetosphere. 2. Density profiles

    Directory of Open Access Journals (Sweden)

    H. Laakso

    2002-11-01

    Full Text Available Using spacecraft potential measurements of the Polar electric field experiment, we investigate electron density variations of key plasma regions within the magnetosphere, including the polar cap, cusp, trough, plasmapause, and auroral zone. The statistical results were presented in the first part of this study, and the present paper reports detailed structures revealed by individual satellite passes. The high-altitude (> 3 RE polar cap is generally one of the most tenuous regions in the magnetosphere, but surprisingly, the polar cap boundary does not appear as a steep density decline. At low altitudes (1 RE in summer, the polar densities are very high, several 100 cm-3 , and interestingly, the density peaks at the central polar cap. On the noonside of the polar cap, the cusp appears as a dense, 1–3° wide region. A typical cusp density above 4 RE distance is between several 10 cm-3 and a few 100 cm-3 . On some occasions the cusp is crossed multiple times in a single pass, simultaneously with the occurrence of IMF excursions, as the cusp can instantly shift its position under varying solar wind conditions, similar to the magnetopause. On the nightside, the auroral zone is not always detected as a simple density cavity. Cavities are observed but their locations, strengths, and sizes vary. Also, the electric field perturbations do not necessarily overlap with the cavities: there are cavities with no field disturbances, as well as electric field disturbances observed with no clear cavitation. In the inner magnetosphere, the density distributions clearly show that the plasmapause and trough densities are well correlated with geomagnetic activity. Data from individual orbits near noon and midnight demonstrate that at the beginning of geomagnetic disturbances, the retreat speed of the plasmapause can be one L-shell per hour, while during quiet intervals the plasmapause can expand anti-earthward at the same speed. For the trough region, it is found

  1. Cryogenic-temperature profiling of high-power superconducting lines using local and distributed optical-fiber sensors

    CERN Document Server

    Chiuchiolo, Antonella; Consales, Marco; Giordano, Michele; Borriello, Anna; Bajas, Hugues; Galtarossa, Andrea; Bajko, Marta; Cusano, Andrea

    2015-01-01

    This contribution presents distributed and multi-point fiber-optic monitoring of cryogenic temperatures along a superconducting power transmission line down to 30 K and over 20 m distance. Multi-point measurements were conducted using fiber Bragg gratings sensors coated with two different functional overlays (epoxy and PMMA) demonstrating cryogenic operation in the range 300 – 4.2 K. Distributed measurements exploited optical frequency-domain reflectometry to analyze the Rayleigh scattering along two concatenated fibers with different coatings (acrylate and polyimide). The integrated system has been placed along the 20 m long cryostat of a superconducting power transmission line, which is currently being tested at the European Organization for Nuclear Research (CERN). Cool-down events from 300 K to 30 K have been successfully measured in space and time, confirming the viability of these approaches to the monitoring of cryogenic temperatures along a superconducting transmission line.

  2. Managing of gas sensing characteristic of a reduced graphene oxide based gas sensor by the change in synthesis condition: A new approach for electronic nose design

    Energy Technology Data Exchange (ETDEWEB)

    Alizadeh, Taher, E-mail: talizadeh@ut.ac.ir [Department of Analytical Chemistry, Faculty of Chemistry, University College of Science, University of Tehran, P.O. Box 14155-6455, Tehran (Iran, Islamic Republic of); Hamedsoltani, Leyla [Department of Applied Chemistry, Faculty of Science, University of Mohaghegh Ardabili, Ardabil (Iran, Islamic Republic of)

    2016-11-01

    Natural graphite was oxidized and exfoliated via two different methods, leading to two types of graphene oxide (GO) materials. The obtained materials were reduced by three different reducing agents including: hydrazine hydrate, ascorbic acid and sodium borohydride, giving thus six kinds of reduced graphene oxide (RGO) materials. The obtained materials were characterized using Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. The RGOs were then used to fabricate different gas sensors and their electrical resistances were recorded upon exposing to various volatile organic compounds vapors (VOCs). Gas sensing selectivity of each RGO was significantly affected by the synthesis condition. The RGO-based sensor array was fabricated and its capability for discrimination of seven kinds of VOCs was evaluated, utilizing principal component analysis and cluster analysis methods. Loading plot indicated that the presence of five RGO-based sensors could effectively discriminate the aimed vapors. The electronic nose, containing five kinds of RGOs, was used for the classification of seven kinds of VOCs at their different concentrations. - Highlights: • Two oxidation procedures and three reducing agents were utilized to produce six kinds of RGOs. • The synthesized different RGOs exhibited significantly different sensing behaviors. • Seven kinds of organic vapors were chosen for the evaluation of discrimination power of EN. • Using PCA, it was found that seven of six RFGOs were appropriate number to use in final EN. • The developed EN was capable of properly discrimination of tested vapors.

  3. Changes in the aromatic profile of espresso coffee as a function of the grinding grade and extraction time: a study by the electronic nose system.

    Science.gov (United States)

    Severini, C; Ricci, I; Marone, M; Derossi, A; De Pilli, T

    2015-03-04

    The changes in chemical attributes and aromatic profile of espresso coffee (EC) were studied taking into account the extraction time and grinding level as independent variables. Particularly, using an electronic nose system, the changes of the global aromatic profile of EC were highlighted. The results shown as the major amounts of organic acids, solids, and caffeine were extracted in the first 8 s of percolation. The grinding grade significantly affected the quality of EC probably as an effect of the particle size distribution and the percolation pathways of water through the coffee cake. The use of an electronic nose system allowed us to discriminate the fractions of the brew as a function of the percolation time and also the regular coffee obtained from different grinding grades. Particularly, the aromatic profile of a regular coffee (25 mL) was significantly affected by the grinding level of the coffee grounds and percolation time, which are two variables under the control of the bar operator.

  4. Time Variations of Observed Hα Line Profiles and Precipitation Depths of Nonthermal Electrons in a Solar Flare

    Science.gov (United States)

    Falewicz, Robert; Radziszewski, Krzysztof; Rudawy, Paweł; Berlicki, Arkadiusz

    2017-10-01

    We compare time variations of the Hα and X-ray emissions observed during the pre-impulsive and impulsive phases of the C1.1-class solar flare on 2013 June 21 with those of plasma parameters and synthesized X-ray emission from a 1D hydrodynamic numerical model of the flare. The numerical model was calculated assuming that the external energy is delivered to the flaring loop by nonthermal electrons (NTEs). The Hα spectra and images were obtained using the Multi-channel Subtractive Double Pass spectrograph with a time resolution of 50 ms. The X-ray fluxes and spectra were recorded by RHESSI. Pre-flare geometric and thermodynamic parameters of the model and the delivered energy were estimated using RHESSI data. The time variations of the X-ray light curves in various energy bands and those of the Hα intensities and line profiles were well correlated. The timescales of the observed variations agree with the calculated variations of the plasma parameters in the flaring loop footpoints, reflecting the time variations of the vertical extent of the energy deposition layer. Our result shows that the fast time variations of the Hα emission of the flaring kernels can be explained by momentary changes of the deposited energy flux and the variations of the penetration depths of the NTEs.

  5. Considerable humidity response of a well-aligned SOMS micro-wire flexible sensor by moisture-induced releasing of trapped electrons.

    Science.gov (United States)

    Chan, Kuei-Lin; Yang, Min-Han; Chiu, Hsin-Tien; Lee, Chi-Young

    2017-08-22

    Sandia Octahedral Molecular Sieves micro-wires (SOMS MWs) that exhibit ultra-high response to moisture and a short response time can be produced easily in an environmentally friendly mass production process. They are excellent candidate materials for use in humidity sensors. SOMS MWs were synthesized using niobium pentoxide as a precursor in concentrated sodium hydroxide solution. To fabricate humidity-sensing devices, electrophoresis was utilized to align the SOMS MWs on a polyethylene terephthalate (PET) substrate. The degree of alignment of SOMS MWs can be tuned by controlling the electric field during electrophoresis. Both well-aligned SOMS MWs (S-1.00) and randomly distributed SOMS MWs (S-0.00) exhibit maximum sensitivities to humidity (RRH/RDRY) of almost 104 and 107 respectively, and both exhibit short response times (34 and 38 s) and recovery times (7 and 10 s); these MWs outperform metal oxide ceramic-based materials in sensing humidity. Furthermore, the humidity response of S-1.00 exceeds that of S-0.00 by three orders of magnitude, and this result cannot be explained with reference to the Grotthuss mechanism. Therefore, the moisture-induced carriers from trapped electrons contribute significantly to the humidity response of SOMS MWs. In addition, with outstanding humidity sensing-performance under extreme bending conditions and superior durability after being bent hundreds of times, the well-aligned SOMS MW sensor is a favorable candidate for emerging multifunctional electronic-skin.

  6. Multiple approaches for enhancing all-organic electronics photoluminescent sensors: simultaneous oxygen and pH monitoring.

    Science.gov (United States)

    Liu, Rui; Xiao, Teng; Cui, Weipan; Shinar, Joseph; Shinar, Ruth

    2013-05-17

    Key issues in using organic light emitting diodes (OLEDs) as excitation sources in structurally integrated photoluminescence (PL)-based sensors are the low forward light outcoupling, the OLEDs' broad electroluminescence (EL) bands, and the long-lived remnant EL that follows an EL pulse. The outcoupling issue limits the detection sensitivity (S) as only ~20% of the light generated within standard OLEDs can be forward outcoupled and used for sensor probe excitation. The EL broad band interferes with the analyte-sensitive PL, leading to a background that reduces S and dynamic range. In particular, these issues hinder designing compact sensors, potentially miniaturizable, that are devoid of optical filters and couplers. We address these shortcomings by introducing easy-to-employ multiple approaches for outcoupling improvement, PL enhancement, and background EL reduction leading to novel, compact all-organic device architectures demonstrated for simultaneous monitoring of oxygen and pH. The sensor comprises simply-fabricated, directionally-emitting, narrower-band, multicolor microcavity OLED excitation and small molecule- and polymer-based organic photodetectors (OPDs) with a more selective spectral response. Additionally, S and PL intensity for oxygen are enhanced by using polystyrene (PS):polyethylene glycol (PEG) blends as the sensing film matrix. By utilizing higher molecular weight PS, the ratio τ0/τ100 (PL decay time τ at 0% O2/τ at 100% O2) that is often used to express S increases ×1.9 to 20.7 relative to the lower molecular weight PS, where this ratio is 11.0. This increase reduces to ×1.7 when the PEG is added (τ0/τ100=18.2), but the latter results in an increase ×2.7 in the PL intensity. The sensor's response time is <10s in all cases. The microporous structure of these blended films, with PEG decorating PS pores, serves a dual purpose. It results in light scattering that reduces the EL that is waveguided in the substrate of the OLEDs and

  7. Classification of X-ray solar flares regarding their effects on the lower ionosphere electron density profile

    Directory of Open Access Journals (Sweden)

    D. P. Grubor

    2008-06-01

    Full Text Available The classification of X-ray solar flares is performed regarding their effects on the Very Low Frequency (VLF wave propagation along the Earth-ionosphere waveguide. The changes in propagation are detected from an observed VLF signal phase and amplitude perturbations, taking place during X-ray solar flares. All flare effects chosen for the analysis are recorded by the Absolute Phase and Amplitude Logger (AbsPal, during the summer months of 2004–2007, on the single trace, Skelton (54.72 N, 2.88 W to Belgrade (44.85 N, 20.38 E with a distance along the Great Circle Path (GCP D≈2000 km in length. The observed VLF amplitude and phase perturbations are simulated by the computer program Long-Wavelength Propagation Capability (LWPC, using Wait's model of the lower ionosphere, as determined by two parameters: the sharpness (β in 1/km and reflection height (H' in km. By varying the values of β and H' so as to match the observed amplitude and phase perturbations, the variation of the D-region electron density height profile Ne(z was reconstructed, throughout flare duration. The procedure is illustrated as applied to a series of flares, from class C to M5 (5×10−5 W/m2 at 0.1–0.8 nm, each giving rise to a different time development of signal perturbation. The corresponding change in electron density from the unperturbed value at the unperturbed reflection height, i.e. Ne(74 km=2.16×108 m−3 to the value induced by an M5 class flare, up to Ne(74 km=4×1010 m−3 is obtained. The β parameter is found to range from 0.30–0.49 1/km and the reflection height H' to vary from 74–63 km. The changes in Ne(z during the flares, within height range z=60 to 90 km are determined, as well.

  8. Classification of X-ray solar flares regarding their effects on the lower ionosphere electron density profile

    Directory of Open Access Journals (Sweden)

    D. P. Grubor

    2008-06-01

    Full Text Available The classification of X-ray solar flares is performed regarding their effects on the Very Low Frequency (VLF wave propagation along the Earth-ionosphere waveguide. The changes in propagation are detected from an observed VLF signal phase and amplitude perturbations, taking place during X-ray solar flares. All flare effects chosen for the analysis are recorded by the Absolute Phase and Amplitude Logger (AbsPal, during the summer months of 2004–2007, on the single trace, Skelton (54.72 N, 2.88 W to Belgrade (44.85 N, 20.38 E with a distance along the Great Circle Path (GCP D≈2000 km in length.

    The observed VLF amplitude and phase perturbations are simulated by the computer program Long-Wavelength Propagation Capability (LWPC, using Wait's model of the lower ionosphere, as determined by two parameters: the sharpness (β in 1/km and reflection height (H' in km. By varying the values of β and H' so as to match the observed amplitude and phase perturbations, the variation of the D-region electron density height profile Ne(z was reconstructed, throughout flare duration. The procedure is illustrated as applied to a series of flares, from class C to M5 (5×10−5 W/m2 at 0.1–0.8 nm, each giving rise to a different time development of signal perturbation.

    The corresponding change in electron density from the unperturbed value at the unperturbed reflection height, i.e. Ne(74 km=2.16×108 m−3 to the value induced by an M5 class flare, up to Ne(74 km=4×1010 m−3 is obtained. The β parameter is found to range from 0.30–0.49 1/km and the reflection height H' to vary from 74–63 km. The changes in Ne(z during the flares, within height range z=60 to 90 km are determined, as well.

  9. Design and Implementation of a Generic Energy-Harvesting Framework Applied to the Evaluation of a Large-Scale Electronic Shelf-Labeling Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    Kamerman Ad

    2010-01-01

    Full Text Available Most wireless sensor networks (WSNs consist of battery-powered nodes and are limited to hundreds of nodes. Battery replacement is a very costly operation and a key factor in limiting successful large-scale deployments. The recent advances in both energy harvesters and low-power communication systems hold promise for deploying large-scale wireless green-powered sensor networks (WGSNs. This will enable new applications and will eliminate environmentally unfriendly battery disposal. This paper explores the use of energy harvesters to scavenge power for nodes in a WSN. The design and implementation of a generic energy-harvesting framework, suited for a WSN simulator as well as a real-life testbed, are proposed. These frameworks are used to evaluate whether a carrier sense multiple access with collision avoidance scheme is sufficiently reliable for use in emerging large-scale energy harvesting electronic shelf label (EHESL systems (i.e., 12000 labels in a star topology. Both the simulator and testbed experiments yielded an average success rate up to 92%, with an arrival rate of 40 transceive cycles per second. We have demonstrated that our generic energy-harvesting framework is useful for WGSN research because the simulator allowed us to verify the achieved results on the real-life testbed and vice versa.

  10. Enhancement of absorption and resistance of motion utilizing a multi-channel opto-electronic sensor to effectively monitor physiological signs during sport exercise

    Science.gov (United States)

    Alzahrani, Abdullah; Hu, Sijung; Azorin-Peris, Vicente; Barrett, Laura; Esliger, Dale; Hayes, Matthew; Akbare, Shafique; Achart, Jérôme; Kuoch, Sylvain

    2015-03-01

    This study presents an effective engineering approach for human vital signs monitoring as increasingly demanded by personal healthcare. The aim of this work is to study how to capture critical physiological parameters efficiently through a well-constructed electronic system and a robust multi-channel opto-electronic patch sensor (OEPS), together with a wireless communication. A unique design comprising multi-wavelength illumination sources and a rapid response photo sensor with a 3-axis accelerometer enables to recover pulsatile features, compensate motion and increase signal-to-noise ratio. An approved protocol with designated tests was implemented at Loughborough University a UK leader in sport and exercise assessment. The results of sport physiological effects were extracted from the datasets of physical movements, i.e. sitting, standing, waking, running and cycling. t-test, Bland-Altman and correlation analysis were applied to evaluate the performance of the OEPS system against Acti-Graph and Mio-Alpha.There was no difference in heart rate measured using OEPS and both Acti-Graph and Mio-Alpha (both p<0.05). Strong correlations were observed between HR measured from the OEPS and both the Acti-graph and Mio-Alpha (r = 0.96, p<0.001). Bland-Altman analysis for the Acti-Graph and OEPS found the bias 0.85 bpm, the standard deviation 9.20 bpm, and the limits of agreement (LOA) -17.18 bpm to +18.88 bpm for lower and upper limits of agreement respectively, for the Mio-Alpha and OEPS the bias is 1.63 bpm, standard deviation SD8.62 bpm, lower and upper limits of agreement, - 15.27 bpm and +18.58 bpm respectively. The OEPS demonstrates a real time, robust and remote monitoring of cardiovascular function.

  11. Ultra-fast electronic detection of antimicrobial resistance genes using isothermal amplification and Thin Film Transistor sensors.

    Science.gov (United States)

    Hu, Chunxiao; Kalsi, Sumit; Zeimpekis, Ioannis; Sun, Kai; Ashburn, Peter; Turner, Carrie; Sutton, J Mark; Morgan, Hywel

    2017-10-15

    A low cost thin-film transistor (TFT) nanoribbon (NR) sensor has been developed for rapid real-time detection of DNA amplification using an isothermal Recombinase Polymerase Amplification (RPA) method. The semiconductor chip measures DNA amplification through a pH change, rather than via fluorescence. The utility of the method was demonstrated by amplifying CTX-M and NDM, two genes that confer bacterial resistance to cephalosporins and carbapenems, respectively. It is shown that this approach provides extremely fast and sensitive detection. It can detect <10 copies of the gene in genomic DNA extracted from E. coli or K. pneumoniae clinical isolates within a few minutes. A differential readout system was developed to minimize the effect of primer-dimer amplification on the assay. The simple device has the potential for low cost, portable and real-time nucleic acid analysis as a Point of Care device. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  12. Time-dependent categorization of volatile aroma compound formation in stewed Chinese spicy beef using electron nose profile coupled with thermal desorption GC–MS detection

    Directory of Open Access Journals (Sweden)

    Hui Gong

    2017-09-01

    Full Text Available In the present study, flavor profiles of Chinese spiced beef in the cooking process were comparatively analyzed by electronic nose, gas chromatography–mass spectrometry (GC–MS with a thermal desorption system (TDS, and solid-phase microextraction (SPME. A total of 82 volatile compounds were identified, and 3-methyl-butanal, pentanal, hexanal, ρ-xylene, heptanal, limonene, terpinene, octanal, linalool, 4-terpinenol, α-terpineol, and (E-anethole were identified as the characteristic flavor compounds in Chinese spiced beef. Variation in the content of volatile components produced by different cooking processes was observed. In general, a cooking time of 4 h resulted in optimal flavor quality and stability. Results indicated that the electronic nose could profile and rapidly distinguish variation among different cooking time. The volatile profiling by TDS-GC–MS and responses from the electronic nose, in combination with multivariate statistical analysis, are a promising tool for control the cooking process of spiced beef.

  13. Assessment of the waste electrical and electronic equipment management systems profile and sustainability in developed and developing European Union countries.

    Science.gov (United States)

    Ibanescu, Dumitrita; Cailean Gavrilescu, Daniela; Teodosiu, Carmen; Fiore, Silvia

    2018-03-01

    The assessment of waste management systems for electrical and electronic equipment (WEEE) from developed economies (Germany, Sweden and Italy) and developing countries (Romania and Bulgaria), is discussed covering the period 2007-2014. The WEEE management systems profiles are depicted by indicators correlated to WEEE life cycle stages: collection, transportation and treatment. The sustainability of national WEEE management systems in terms of greenhouse gas emissions is presented, together with the greenhouse gas efficiency indicator that underlines the efficiency of WEEE treatment options. In the countries comparisons, the key elements are: robust versus fragile economies, the overall waste management performance and the existence/development of suitable management practices on WEEE. Over the life cycle perspective, developed economies (Germany, Sweden and Italy) manage one order of magnitude higher quantities of WEEE compared to developing countries (Romania and Bulgaria). Although prevention and reduction measures are encouraged, all WEEE quantities were larger in 2013, than in 2007. In 2007-2014, developed economies exceed the annual European collection target of 4 kg WEEE/capita, while collection is still difficult in developing countries. If collection rates are estimated in relationship with products placed on market, than similar values are registered in Sweden and Bulgaria, followed by Germany and Italy and lastly Romania. WEEE transportation shows different patterns among countries, with Italy as the greatest exporter (in 2014), while Sweden treats the WEEE nationally. WEEE reuse is a common practice in Germany, Sweden (from 2009) and Bulgaria (from 2011). By 2014, recycling was the most preferred WEEE treatment option, with the same kind of rates performance, over 80%, irrespective of the country, with efforts in each of the countries in developing special collection points, recycling facilities and support instruments. The national total and the

  14. Analytic approach to magneto-strain tuning of electronic transport through a graphene nanobubble: perspectives for a strain sensor

    Science.gov (United States)

    Muñoz, Enrique; Soto-Garrido, Rodrigo

    2017-11-01

    We consider the scattering of Dirac particles in graphene due to the superposition of an external magnetic field and mechanical strain. As a model for a graphene nanobubble, we find exact analytical solutions for single-particle states inside and outside a circular region submitted to the fields. Finally, we obtain analytical expressions for the scattering cross-section, as well as for the Landauer current through the circular region. Our results provide a fully-analytical treatment for electronic transport through a graphene nanobubble, showing that a combination of a physical magnetic field and strain leads to valley polarization and filtering of the electronic current. Moreover, our analytical model provides an explicit metrology principle to measure strain by performing conductance experiments under a controlled magnetic field imposed over the sample.

  15. Note: A non-invasive electronic measurement technique to measure the embedded four resistive elements in a Wheatstone bridge sensor

    Science.gov (United States)

    Ravelo Arias, S. I.; Ramírez Muñoz, D.; Cardoso, S.; Ferreira, R.; Freitas, P.

    2015-06-01

    The work shows a measurement technique to obtain the correct value of the four elements in a resistive Wheatstone bridge without the need to separate the physical connections existing between them. Two electronic solutions are presented, based on a source-and-measure unit and using discrete electronic components. The proposed technique brings the possibility to know the mismatching or the tolerance between the bridge resistive elements and then to pass or reject it in terms of its related common-mode rejection. Experimental results were taken in various Wheatstone resistive bridges (discrete and magnetoresistive integrated bridges) validating the proposed measurement technique specially when the bridge is micro-fabricated and there is no physical way to separate one resistive element from the others.

  16. Note: A non-invasive electronic measurement technique to measure the embedded four resistive elements in a Wheatstone bridge sensor

    Energy Technology Data Exchange (ETDEWEB)

    Ravelo Arias, S. I.; Ramírez Muñoz, D. [Department of Electronic Engineering, University of Valencia, Avda. de la Universitat, s/n, 46100-Burjassot (Spain); Cardoso, S. [INESC Microsystems and Nanotechnologies (INESC-MN) and Institute for Nanosciences and Nanotechnologies, R. Alves Redol 9, Lisbon 1000-029 (Portugal); Ferreira, R. [INL-International Iberian Nanotechnology Laboratory, Av. Mestre José Veiga, Braga 4715-31 (Portugal); Freitas, P. [INESC Microsystems and Nanotechnologies (INESC-MN) and Institute for Nanosciences and Nanotechnologies, R. Alves Redol 9, Lisbon 1000-029 (Portugal); INL-International Iberian Nanotechnology Laboratory, Av. Mestre José Veiga, Braga 4715-31 (Portugal)

    2015-06-15

    The work shows a measurement technique to obtain the correct value of the four elements in a resistive Wheatstone bridge without the need to separate the physical connections existing between them. Two electronic solutions are presented, based on a source-and-measure unit and using discrete electronic components. The proposed technique brings the possibility to know the mismatching or the tolerance between the bridge resistive elements and then to pass or reject it in terms of its related common-mode rejection. Experimental results were taken in various Wheatstone resistive bridges (discrete and magnetoresistive integrated bridges) validating the proposed measurement technique specially when the bridge is micro-fabricated and there is no physical way to separate one resistive element from the others.

  17. Average profiles of the solar wind and outer radiation belt during the extreme flux enhancement of relativistic electrons at geosynchronous orbit

    Directory of Open Access Journals (Sweden)

    R. Kataoka

    2008-06-01

    Full Text Available We report average profiles of the solar wind and outer radiation belt during the extreme flux enhancement of relativistic electrons at geosynchronous orbit (GEO. It is found that seven of top ten extreme events at GEO during solar cycle 23 are associated with the magnetosphere inflation during the storm recovery phase as caused by the large-scale solar wind structure of very low dynamic pressure (<1.0 nPa during rapid speed decrease from very high (>650 km/s to typical (400–500 km/s in a few days. For the seven events, the solar wind parameters, geomagnetic activity indices, and relativistic electron flux and geomagnetic field at GEO are superposed at the local noon period of GOES satellites to investigate the physical cause. The average profiles support the "double inflation" mechanism that the rarefaction of the solar wind and subsequent magnetosphere inflation are one of the best conditions to produce the extreme flux enhancement at GEO because of the excellent magnetic confinement of relativistic electrons by reducing the drift loss of trapped electrons at dayside magnetopause.

  18. Front-end electronics in a 65 nm CMOS process for high density readout of pixel sensors

    Science.gov (United States)

    Gaioni, Luigi; Manghisoni, Massimo; Ratti, Lodovico; Re, Valerio; Traversi, Gianluca

    2011-09-01

    In future high energy physics experiments (HEP), readout integrated circuits for vertexing and tracking applications will be implemented by means of CMOS devices belonging to processes with minimum feature size in the 100 nm span. In these nanoscale technologies the impact of new dielectric materials and processing techniques on the analog behavior of MOSFETs has to be carefully evaluated. This paper is concerned with the study of the analog properties, in particular in terms of noise performance and radiation hardness, of MOSFET devices belonging to a 65 nm CMOS low power technology. The behavior of the 1/ f and white noise terms is studied as a function of the main device parameters before and after exposure to 10 keV X-rays and 60Co γ-rays. A prototype chip designed in a 65 nm CMOS process including deep n-well MAPS structures and a fast front-end conceived for the readout of high-resistivity pixel sensors will be introduced.

  19. Temperature profile data from surface sensors and CTD casts from the Gulf of Alaska from NOAA Ship MILLER FREEMAN as part of the Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 1990-04-17 to 1990-10-11 (NODC Accession 9100188)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile data were collected from surface sensors and CTD casts in the Gulf of Alaska from NOAA Ship MILLER FREEMAN from 17 April 1990 to 11 October 1990....

  20. Temperature profile and other data from surface sensors and CTD casts from NOAA Ship MILLER FREEMAN and other platforms as part of the Outer Continental Shelf Environmental Assessment Program (OCSEAP) and the Fisheries-Oceanography Cooperative Investigations (FOCI) from 1988-01-31 to 1989-09-23 (NODC Accession 9000273)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile and other data were collected from surface sensors and CTD casts from NOAA Ship MILLER FREEMAN and other platforms from 31 January 1988 to 23...

  1. Temperature profile data from surface sensors, bottle casts, and CTD casts from the Bering Sea from the R/V ALPHA HELIX as part of the Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 21 April 1988 to 20 May 1988 (NODC Accession 8800172)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile data were collected from surface sensors, bottle casts, and CTD casts in the Bering Sea from the R/V ALPHA HELIX from 21 April 1988 to 20 May...

  2. Tunable electronic and optical properties of gas molecules adsorbed monolayer graphitic ZnO: Implications for gas sensor and environment monitoring

    Science.gov (United States)

    Zhang, Wei; Du, Qikui; Zhang, Lifa

    2017-12-01

    Due to the large surface area and the peculiar electronic characters, great attention has been paid to 2D materials for the gas sensing applications. Here, using the hybrid density functional calculations, we systematically study the adsorptions of gas molecules on the monolayer graphitic ZnO (g-ZnO), including CO, H2, H2O, H2S, NH3, NO, NO2, O2, and SO2. For most of the molecules, g-ZnO shows superior sensing performance to the well-known MoS2, black phosphorus, blue phosphorus, antimonene, and germanene. H2S, NO, NO2, and SO2 act as charge acceptors, and CO, H2, H2O, and NH3 serve as charge donors. These molecules also induce distinct modifications to the electronic structures, work functions, and optical adsorptions. NO, NO2, and O2 form flat bands in the bandgaps of the spin-up or spin-down states, whereas other molecules mainly tune the bandgaps and the orbital couplings. In particular, g-ZnO is most likely to adsorb the atmospheric pollutant SO2, which has the strongest interaction through hybridizing its widely broadened 2p orbitals with the 3d orbitals of g-ZnO. Moreover, the improved visible light absorption is demonstrated in the NO2 adsorbed g-ZnO. Our results not only confirm that the electronic and optical properties of g-ZnO can be effectively tuned by the selective adsorption of gas molecules but also provide insightful guidance for the potential application of g-ZnO in the field of gas sensors.

  3. An improved version of the Shadow Position Sensor readout electronics on-board the ESA PROBA-3 Mission

    Science.gov (United States)

    Noce, V.; Focardi, M.; Buckley, S.; Bemporad, A.; Fineschi, S.; Pancrazzi, M.; Landini, F.; Baccani, C.; Capobianco, G.; Loreggia, D.; Casti, M.; Romoli, M.; Accatino, L.; Thizy, C.; Denis, F.; Ledent, P.

    2017-08-01

    PROBA-3 [1] [2] is a Mission of the European Space Agency (ESA) composed by two satellites flying in formation and aimed at achieving unprecedented performance in terms of relative positioning. The mission purpose is, in first place, technological: the repeated formation break and acquisition during each orbit (every about twenty hours) will be useful to demonstrate the efficacy of the closed-loop control system in keeping the formation-flying (FF) and attitude (i.e. the alignment with respect to the Sun) of the system. From the scientific side, instead, the two spacecraft will create a giant instrument about 150 m long: an externally occulted coronagraph named ASPIICS (Association of Spacecraft for Polarimetric and Imaging Investigation of the Corona of the Sun) dedicated to the study of the inner part of the visible solar corona. The two satellites composing the mission are: the Coronagraph Spacecraft (CSC), hosting the Coronagraph Instrument (CI), and the disk-shaped (1.4 m diameter) Occulter Spacecraft (OSC). The PROBA-3 GNC (Guidance, Navigation and Control) system will employ several metrological subsystems to keep and retain the desired relative position and the absolute attitude (i.e. with respect to the Sun) of the aligned spacecraft, when in observational mode. The SPS subsystem [5] is one of these metrological instruments. It is composed of eight silicon photomultipliers (SiPMs), sensors operated in photovoltaic mode [6] that will sense the penumbra light around the Instrument's pupil so to detect any FF displacement from the nominal position. In proximity of the CDR (Critical Design Review) phase, we describe in the present paper the changes occurred to design in the last year in consequence of the tests performed on the SPS Breadboard (Evaluation Board, EB) and the SPS Development Model (DM) and that will finally lead to the realization of the flight version of the SPS system.

  4. Determination of a partial electronic conduction parameter of solid electrolytes for an oxygen sensor by using AC two terminals method. Koryu 2 tanshi ho ni yoru sanso sensor yo kotai denkaishitsu no denshi dendo sei parameter no sokutei

    Energy Technology Data Exchange (ETDEWEB)

    Sasabe, M. (Chiba Inst. of Tech., Chiba (Japan)); Miyashita, M. (Toshiba Tungalloy Co. Ltd., Kawasaki (Japan)); Hua, J.Z. (Harbin Inst. of Tech., Harbin (China)); Senoo, H. (Osaka Sanso Kogyo Ltd., Osaka (Japan))

    1991-06-01

    An oxygen sensor with a built-in oxygen concentration cell using solid zirconia electrolyte can measure oxygen activity by immersing it in molten steel for ten and some seconds. For measuring oxygen in molten steel, the value of partial electronic conduction parameter of solid electrolyte is important. So far the swinkels method using the polarization electromotive force has been used for measurement, but it has several problematical points. In this research, in order to solve them, a new measuring method of electroconductive parameters of solid electrolyte by the AC two terminal method was designed and measurement was done on various zirconia based solid electrolytes. It was clarified that this method has the following features: The measured values by this method agree with those by the swinkels method which had so far been the sole measuring method. The sufficient size of the electrolyte for the measurement is 2mm in diameter and 10mm in length or more, and in comparison with the swinkels method, a fairly small specimen can be meamsured. There is no restriction on the shape of electrolyte and this method does not dirty solid electrolyte. Its measuring time is shorter than the swinkels method. 17 refs., 13 figs., 2 tabs.

  5. Corrosion sensor

    Science.gov (United States)

    Glass, Robert S.; Clarke, Jr., Willis L.; Ciarlo, Dino R.

    1994-01-01

    A corrosion sensor array incorporating individual elements for measuring various elements and ions, such as chloride, sulfide, copper, hydrogen (pH), etc. and elements for evaluating the instantaneous corrosion properties of structural materials. The exact combination and number of elements measured or monitored would depend upon the environmental conditions and materials used which are subject to corrosive effects. Such a corrosion monitoring system embedded in or mounted on a structure exposed to the environment would serve as an early warning system for the onset of severe corrosion problems for the structure, thus providing a safety factor as well as economic factors. The sensor array is accessed to an electronics/computational system, which provides a means for data collection and analysis.

  6. Auger electron spectroscopy study of oxidation of a PdCr alloy used for high-temperature sensors

    Science.gov (United States)

    Boyd, Darwin L.; Zeller, Mary V.; Vargas-Aburto, Carlos

    1993-01-01

    A Pd-13 wt. percent Cr solid solution is a promising high-temperature strain gage alloy. In bulk form it has a number of properties that are desirable in a resistance strain gage material, such as a linear electrical resistance versus temperature curve to 1000 C and stable electrical resistance in air at 1000 C. However, unprotected fine wire gages fabricated from this alloy perform well only to 600 C. At higher temperatures severe oxidation degrades their electrical performance. In this work Auger electron spectroscopy was used to study the oxidation chemistry of the alloy wires and ribbons. Results indicate that the oxidation is caused by a complex mechanism that is not yet fully understood. As expected, during oxidation, a layer of chromium oxide is formed. This layer, however, forms beneath a layer of metallic palladium. The results of this study have increased the understanding of the oxidation mechanism of Pd-13 wt. percent Cr.

  7. Layered composites of PEDOT/PSS/nanoparticles and PEDOT/PSS/phthalocyanines as electron mediators for sensors and biosensors

    Directory of Open Access Journals (Sweden)

    Celia García-Hernández

    2016-12-01

    Full Text Available The sensing properties of electrodes chemically modified with PEDOT/PSS towards catechol and hydroquinone sensing have been successfully improved by combining layers of PEDOT/PSS with layers of a secondary electrocatalytic material such as gold nanoparticles (PEDOT/PSS/AuNPs, copper phthalocyanine (PEDOT/PSS/CuPc or lutetium bisphthalocyanine (PEDOT/PSS/LuPc2. Layered composites exhibit synergistic effects that strongly enhance the electrocatalytic activity as indicated by the increase in intensity and the shift of the redox peaks to lower potentials. A remarkable improvement has been achieved using PEDOT/PSS/LuPc2, which exhibits excellent electrocatalytic activity towards the oxidation of catechol. The kinetic studies demonstrated diffusion-controlled processes at the electrode surfaces. The kinetic parameters such as Tafel slopes and charge transfer coefficient (α confirm the improved electrocatalytic activity of the layered electron mediators. The peak currents increased linearly with concentration of catechol and hydroquinone over the range of 1.5 × 10−4 to 4.0 × 10−6 mol·L−1 with a limit of detection on the scale of μmol·L−1. The layered composite hybrid systems were also found to be excellent electron mediators in biosensors containing tyrosinase and laccase, and they combine the recognition and biocatalytic properties of biomolecules with the unique catalytic features of composite materials. The observed increase in the intensity of the responses allowed detection limits of 1 × 10−7 mol·L−1 to be attained.

  8. Control of quasi-monoenergetic electron beams from laser-plasma accelerators by adjusting shock density profile

    Science.gov (United States)

    Tsai, Hai-En; Swanson, Kelly K.; Lehe, Remi; Barber, Sam K.; Isono, Fumika; Otero, Jorge G.; Liu, Xinyao; Mao, Hann-Shin; Steinke, Sven; Tilborg, Jeroen Van; Geddes, Cameron G. R.; Leemans, Wim

    2017-10-01

    High-level control of a laser-plasma accelerator (LPA) using a shock injector was demonstrated by systematically varying the shock injector profile, including the shock angle, up-ramp width and shock position. Particle-in-cell (PIC) simulation explored how variations in the shock profile impacted the injection process and confirmed results obtained through acceleration experiments. These results establish that, by adjusting shock position, up-ramp, and angle, beam energy, energy spread, and pointing can be controlled. As a result, e-beam were highly tunable from 25 to 300 MeV with Security Administration, Defense Nuclear Nonproliferation R&D (NA22).

  9. Interfacing Sensors To Micro Controllers

    KAUST Repository

    Norain, Mohamed

    2018-01-15

    This lecture will cover the most common interface and interface techniques between sensors and microcontrollers. The presentation will introduce the pros and cons of each interface type including analogue, digital and serial output sensors. It will also cover the basic required electronics knowledge to help you in selecting and designing your next sensor to microcontroller interface.

  10. Low-Cost Humidity Sensor

    Science.gov (United States)

    Laue, E. G.

    1986-01-01

    Electronic humidity sensor is simple, inexpensive, and produces output readily used by indicator or control circuits. Sensor operates at safe, low voltage and is relatively invulnerable to electrolysis effects. Sensor used to measure humidity in atmosphere, in soil, and industrial gases, for example.

  11. Virtual Sensor Test Instrumentation

    Science.gov (United States)

    Wang, Roy

    2011-01-01

    Virtual Sensor Test Instrumentation is based on the concept of smart sensor technology for testing with intelligence needed to perform sell-diagnosis of health, and to participate in a hierarchy of health determination at sensor, process, and system levels. A virtual sensor test instrumentation consists of five elements: (1) a common sensor interface, (2) microprocessor, (3) wireless interface, (4) signal conditioning and ADC/DAC (analog-to-digital conversion/ digital-to-analog conversion), and (5) onboard EEPROM (electrically erasable programmable read-only memory) for metadata storage and executable software to create powerful, scalable, reconfigurable, and reliable embedded and distributed test instruments. In order to maximize the efficient data conversion through the smart sensor node, plug-and-play functionality is required to interface with traditional sensors to enhance their identity and capabilities for data processing and communications. Virtual sensor test instrumentation can be accessible wirelessly via a Network Capable Application Processor (NCAP) or a Smart Transducer Interlace Module (STIM) that may be managed under real-time rule engines for mission-critical applications. The transducer senses the physical quantity being measured and converts it into an electrical signal. The signal is fed to an A/D converter, and is ready for use by the processor to execute functional transformation based on the sensor characteristics stored in a Transducer Electronic Data Sheet (TEDS). Virtual sensor test instrumentation is built upon an open-system architecture with standardized protocol modules/stacks to interface with industry standards and commonly used software. One major benefit for deploying the virtual sensor test instrumentation is the ability, through a plug-and-play common interface, to convert raw sensor data in either analog or digital form, to an IEEE 1451 standard-based smart sensor, which has instructions to program sensors for a wide variety of

  12. Spot profile analysis and lifetime mapping in ultrafast electron diffraction: Lattice excitation of self-organized Ge nanostructures on Si(001

    Directory of Open Access Journals (Sweden)

    T. Frigge

    2015-05-01

    Full Text Available Ultrafast high energy electron diffraction in reflection geometry is employed to study the structural dynamics of self-organized Germanium hut-, dome-, and relaxed clusters on Si(001 upon femtosecond laser excitation. Utilizing the difference in size and strain state the response of hut- and dome clusters can be distinguished by a transient spot profile analysis. Surface diffraction from {105}-type facets provide exclusive information on hut clusters. A pixel-by-pixel analysis of the dynamics of the entire diffraction pattern gives time constants of 40, 160, and 390 ps, which are assigned to the cooling time constants for hut-, dome-, and relaxed clusters.

  13. Review of Recent Metamaterial Microfluidic Sensors.

    Science.gov (United States)

    Salim, Ahmed; Lim, Sungjoon

    2018-01-15

    Metamaterial elements/arrays exhibit a sensitive response to fluids yet with a small footprint, therefore, they have been an attractive choice to realize various sensing devices when integrated with microfluidic technology. Micro-channels made from inexpensive biocompatible materials avoid any contamination from environment and require only microliter-nanoliter sample for sensing. Simple design, easy fabrication process, light weight prototype, and instant measurements are advantages as compared to conventional (optical, electrochemical and biological) sensing systems. Inkjet-printed flexible sensors find their utilization in rapidly growing wearable electronics and health-monitoring flexible devices. Adequate sensitivity and repeatability of these low profile microfluidic sensors make them a potential candidate for point-of-care testing which novice patients can use reliably. Aside from degraded sensitivity and lack of selectivity in all practical microwave chemical sensors, they require an instrument, such as vector network analyzer for measurements and not readily available as a self-sustained portable sensor. This review article presents state-of-the-art metamaterial inspired microfluidic bio/chemical sensors (passive devices ranging from gigahertz to terahertz range) with an emphasis on metamaterial sensing circuit and microfluidic detection. We also highlight challenges and strategies to cope these issues which set future directions.

  14. Nanostructured SnO2 thick films for gas sensor application: analysis of structural and electronic properties

    Science.gov (United States)

    Miskovic, Goran; Aleksic, Obrad S.; Nikolic, Maria V.; Nicolics, Johann; Radosavljevic, Goran; Vasiljevic, Zorka Z.; Lukovic, Miloljub D.; Smetana, Walter

    2016-03-01

    This research is focused on structural and electrical characterisation of tin oxide (SnO2) applied as a thick film and investigation of its properties as gas sensitive material. Micron sized SnO2 powder was milled in an agate mill for six hours to fabricate SnO2 nanopowder, which was afterwards sieved by 325 mesh sieve and characterized by XRD and SEM. This powder was used as functional part in the production of thick film tin oxide paste containing a resin vehicle with 4 wt. % nanosize glass frits acting as permanent binder. The glass frits where additionally milled for twelve hours in the agate mills to nanosized powder and sieved by a 325 mesh sieve as well. The achieved thick film paste was screen printed on alumina and fired at 850oC peak temperature for 10 minutes in air. After the sintering process, thick film samples where characterized by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). The reflectivity was measured on the same samples by UV-VIS spectrophotometer: the band gap was determined from the slope of reflectance. After that a matrix of different interdigitated electrode structure of PdAg paste was printed and sintered using the mentioned sintering conditions. The tin oxide thick film was printed over the interdigitated electrodes as a top layer and sintered again under the same conditions. The total electrical resistance was measured as a function of the electrode spacing and temperature. A negative temperature coefficient (NTC) was identified and measured in the range from room temperature (27°C) to 180°C in a climate chamber. Finally the samples were placed into a gas reactor with NOx and CO gas and the resistance was measured in the same temperature range (27°C-200°C).

  15. [Sensors for Measuring Taste and Smell].

    Science.gov (United States)

    Toko, Kiyoshi

    2017-05-01

    Gustatory and olfactory senses receive chemical substances at the biological membranes of taste and olfactory cells, respectively. The present review article describes electronic tongue (taste sensor) and electronic nose (odor sensor) developed based on biomimetic technology. A taste sensor is now commercially sold and utilized in pharmaceutical and food companies across the world. An electronic nose with high sensitivity was also commercialized in Japan. These sensors provide novel methods for analyzing chemical substances instead of using conventional tools.

  16. Electronic Band Profile and Optical Response of Spinel MgIn2O4 through Modified Becke—Johnson Potential

    Science.gov (United States)

    Manzar, A.; Murtaza, G.; Khenata, R.; S., Muhammad; Hayatullah

    2013-06-01

    We employ the first-principles technique based on the modified Becke—Johnson (BJ) exchange potential for the prediction of the electronic band structure, optical properties, and electron density of the cubic MgIn2O4 spinel compound. It is found that the calculated band gap value with the modified BJ approximation is significantly improved over the results based on the generalized gradient approximation and the local density approximation in comparison to the experimental data. The band gap dependent optical parameters such as the dielectric constant, refractive index, reflectivity, optical conductivity, and electron density are predicted. The optical response suggests that MgIn2O4 is an applicant material in optoelectronic devices in various parts of the energy spectrum like MgAl2O4 and MgGa2O4.

  17. Design of a High-Perveance Electron Gun for Electron Cooling in the Low Energy Ion Ring (LEIR) at CERN and Non-Interceptive Proton Beam Profile Monitors using Ion or Atomic Probe Beams

    CERN Document Server

    Dimopoulou, Christina

    2002-01-01

    For an efficient electron cooling of the low-energy Pb54+ ions in LEIR a high-perveance (at least 3.6microperv) electron gun had to be designed. The theoretical study of electron guns has shown that the required perveance can be achieved by using a convex cathode. The gun should be immersed in a strong magnetic field (B=2-6kG) in order to obtain a parallel beam with very low transverse energy (typically 0.1 eV). This idea was confirmed by experimental tests at Fermilab. An adiabatic magnetic expansion is foreseen after the gun in order to reduce the magnetic field to accpetable values (0.6-1 kG) in the cooling section. The internal geometry of a convex cathode gun for the LEIR electron cooler together with the parameters of the magnetic expansion are proposed. The scheme fulfils the requirements. In addition, the author has made an important contribution in the field of beam instrumentation for the LHC and other accelerators at CERN. A profile monitor has been developed that uses a Xe ion probe beam that inte...

  18. Clementine sensor suite

    Energy Technology Data Exchange (ETDEWEB)

    Ledebuhr, A.G. [Lawrence Livermore National Lab., CA (United States)

    1994-11-15

    LLNL designed and built the suite of six miniaturized light-weight space-qualified sensors utilized in the Clementine mission. A major goal of the Clementine program was to demonstrate technologies originally developed for Ballistic Missile Defense Organization Programs. These sensors were modified to gather data from the moon. This overview presents each of these sensors and some preliminary on-orbit performance estimates. The basic subsystems of these sensors include optical baffles to reject off-axis stray light, light-weight ruggedized optical systems, filter wheel assemblies, radiation tolerant focal plane arrays, radiation hardened control and readout electronics and low mass and power mechanical cryogenic coolers for the infrared sensors. Descriptions of each sensor type are given along with design specifications, photographs and on-orbit data collected.

  19. Flexible magnetoimpedance sensor

    KAUST Repository

    Li, Bodong

    2015-03-01

    Flexible magnetoimpedance (MI) sensors fabricated using a NiFe/Cu/NiFe tri-layer on Kapton substrate have been studied. A customized flexible microstrip transmission line was employed to investigate the MI sensors\\'s magnetic field and frequency responses and their dependence on the sensors\\'s deflection. For the first time, the impedance characteristic is obtained through reflection coefficient analysis over a wide range of frequencies from 0.1 MHz to 3 GHz and for deflections ranging from zero curvature to a radius of 7.2 cm. The sensor element maintains a high MI ratio of up to 90% and magnetic sensitivity of up to 9.2%/Oe over different bending curvatures. The relationship between the curvature and material composition is discussed based on the magnetostriction effect and stress simulations. The sensor\\'s large frequency range, simple fabrication process and high sensitivity provide a great potential for flexible electronics and wireless applications.

  20. Wireless Sensor Node Power Profiling Based on IEEE 802.11 and IEEE 802.15.4 Communication Protocols. Modeling and Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Agarwal, Vivek [Idaho National Lab. (INL), Idaho Falls, ID (United States); Richardson, Joseph [Idaho National Lab. (INL), Idaho Falls, ID (United States); Zhang, Yanliang [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-10-01

    Most wireless sensor network (comprising of thousands of WSNs) applications require operation over extended periods of time beginning with their deployment. Network lifetime is extremely critical for most applications and is one of the limiting factors for energy-constrained networks. Based on applications, there are wide ranges of different energy sources suitable for powering WSNs. A battery is traditionally used to power WSNs. The deployed WSN is required to last for long time. Due to finite amount of energy present in batteries, it is not feasible to replace batteries. Recently there has been a new surge in the area of energy harvesting were ambient energy in the environment can be utilized to prolong the lifetime of WSNs. Some of the sources of ambient energies are solar power, thermal gradient, human motion and body heat, vibrations, and ambient RF energy. The design and development of TEGs to power WSNs that would remain active for a long period of time requires comprehensive understanding of WSN operational. This motivates the research in modeling the lifetime, i.e., power consumption, of a WSN by taking into consideration various node and network level activities. A WSN must perform three essential tasks: sense events, perform quick local information processing of sensed events, and wirelessly exchange locally processed data with the base station or with other WSNs in the network. Each task has a power cost per unit tine and an additional cost when switching between tasks. There are number of other considerations that must also be taken into account when computing the power consumption associated with each task. The considerations includes: number of events occurring in a fixed active time period and the duration of each event, event-information processing time, total communication time, number of retransmission, etc. Additionally, at the network level the communication of information data packets between WSNs involves collisions, latency, and

  1. Auroral E-region electron density height profile modificationby electric field driven vertical plasma transport:some evidence in EISCAT CP-1 data statistics

    Directory of Open Access Journals (Sweden)

    T. Bösinger

    2004-03-01

    Full Text Available A model developed several years ago by Huuskonen et al. (1984 predicted that vertical transport of ions in the nocturnal auroral E-region ionosphere can shift the electron density profiles in altitude during times of sufficiently large electric fields. If the vertical plasma transport effect was to operate over a sufficiently long enough time, then the real height of the E-region electron maximum should be shifted some km upwards (downwards in the eastward (westward auroral electrojet, respectively, when the electric field is strong, exceeding, say, 50 mV/m. Motivated by these predictions and the lack of any experimental verification so far, we made use of the large database of the European Incoherent Scatter (EISCAT radar to investigate if the anticipated vertical plasma transport is at work in the auroral E-region ionosphere and thus to test the Huuskonen et al. (1984 model. For this purpose a new type of EISCAT data display was developed which enabled us to order a large number of electron density height profiles, collected over 16 years of EISCAT operation, according to the electric field magnitude and direction as measured at the same time at the radar's magnetic field line in the F-region. Our analysis shows some signatures in tune with a vertical plasma transport in the auroral E-region of the type predicted by the Huuskonen et al. model. The evidence brought forward is, however, not unambiguous and requires more rigorous analysis.

    Key words. Ionosphere (auroral ionosphere; plasma convection; electric fields and currents

  2. Duschinsky, Herzberg-Teller, and Multiple Electronic Resonance Interferential Effects in Resonance Raman Spectra and Excitation Profiles. The Case of Pyrene.

    Science.gov (United States)

    Avila Ferrer, Francisco J; Barone, Vincenzo; Cappelli, Chiara; Santoro, Fabrizio

    2013-08-13

    We show that a recently developed time-independent approach for the calculation of vibrational resonance Raman (vRR) spectra is able to describe Duschinsky and Herzberg-Teller (HT) effects acting on a single resonant state, together with interferential contributions arising from multiple electronic resonances, allowing us to investigate in detail how their interplay determines both the vRR spectra at selected wavelengths and the Raman excitation profiles. We apply this methodology to the study of the spectra of pyrene in acetonitrile, an ideal system since it exhibits three close-lying electronic transitions that are bright but also subjected to HT effects. To single out the different contributions to vRR line shapes we adopted two different adiabatic models for resonant-state potential energy surfaces, namely, Adiabatic Shift (only accounting from equilibrium geometry displacements) and Adiabatic Hessian (AH, including also the Duschinsky effects), and Franck-Condon (FC) or HT approximations for the transition dipole. We show that, on balance, FC+HT calculations within the AH model provide the best agreement with experiment. Moreover, our methodology permits to individuate bands in the experimental spectra due to the simultaneous contribution of more than one resonant state and to point out and analyze interferential effects between the FC and HT terms in each resonance Raman process, together with FC-HT and HT-HT interferences between different electronic states.

  3. GLL RPT IONOSPHERE PROFILES

    Data.gov (United States)

    National Aeronautics and Space Administration — The Galileo Radio Propagation Team Ionosphere Profile data set is small number of electron density profiles derived from radio occultation data collected while...

  4. Aerospace Sensor Systems: From Sensor Development To Vehicle Application

    Science.gov (United States)

    Hunter, Gary W.

    2008-01-01

    This paper presents an overview of years of sensor system development and application for aerospace systems. The emphasis of this work is on developing advanced capabilities for measurement and control of aeropropulsion and crew vehicle systems as well as monitoring the safety of those systems. Specific areas of work include chemical species sensors, thin film thermocouples and strain gages, heat flux gages, fuel gages, SiC based electronic devices and sensors, space qualified electronics, and MicroElectroMechanical Systems (MEMS) as well as integrated and multifunctional sensor systems. Each sensor type has its own technical challenges related to integration and reliability in a given application. The general approach has been to develop base sensor technology using microfabrication techniques, integrate sensors with "smart" hardware and software, and demonstrate those systems in a range of aerospace applications. Descriptions of the sensor elements, their integration into sensors systems, and examples of sensor system applications will be discussed. Finally, suggestions related to the future of sensor technology will be given. It is concluded that smart micro/nano sensor technology can revolutionize aerospace applications, but significant challenges exist in maturing the technology and demonstrating its value in real-life applications.

  5. Laboratory Connections: Gas Monitoring Transducers: Relative Humidity Sensors.

    Science.gov (United States)

    Powers, Michael H.; Hull, Stacey E.

    1988-01-01

    Explains the operation of five relative humidity sensors: psychrometer, hair hygrometer, resistance hygrometer, capacitance hygrometer, and resistance-capacitance hygrometer. Outlines the theory behind the electronic sensors and gives computer interfacing information. Lists sensor responses for calibration. (MVL)

  6. Sulfur-based mixotrophic denitrification corresponding to different electron donors and microbial profiling in anoxic fluidized-bed membrane bioreactors.

    Science.gov (United States)

    Zhang, Lili; Zhang, Chao; Hu, Chengzhi; Liu, Huijuan; Bai, Yaohui; Qu, Jiuhui

    2015-11-15

    Sulfur-based mixotrophic denitrifying anoxic fluidized bed membrane bioreactors (AnFB-MBR) were developed for the treatment of nitrate-contaminated groundwater with minimized sulfate production. The nitrate removal rates obtained in the methanol- and ethanol-fed mixotrophic denitrifying AnFB-MBRs reached 1.44-3.84 g NO3 -N/L reactor d at a hydraulic retention time of 0.5 h, which were significantly superior to those reported in packed bed reactors. Compared to methanol, ethanol was found to be a more effective external carbon source for sulfur-based mixotrophic denitrification due to lower sulfate and total organic carbon concentrations in the effluent. Using pyrosequencing, the phylotypes of primary microbial groups in the reactor, including sulfur-oxidizing autotrophic denitrifiers, methanol- or ethanol-supported heterotrophic denitrifiers, were investigated in response to changes in electron donors. Principal component and heatmap analyses indicated that selection of electron donating substrates largely determined the microbial community structure. The abundance of Thiobacillus decreased from 45.1% in the sulfur-oxidizing autotrophic denitrifying reactor to 12.0% and 14.2% in sulfur-based methanol- and ethanol-fed mixotrophic denitrifying bioreactors, respectively. Heterotrophic Methyloversatilis and Thauera bacteria became more dominant in the mixotrophic denitrifying bioreactors, which were possibly responsible for the observed methanol- and ethanol-associated denitrification. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Medical Sensor Network Infrastructures

    DEFF Research Database (Denmark)

    Andersen, Jacob

    is required, such as taking a blood sample, mailing it to a lab, where it is analysed and the result returned by mail. Due to the continuing size and cost reduction of electronic equipment, future medical sensors will be much smaller, cheaper and often disposable. Furthermore, integration of these sensors...... with the electronic health record (EHR) IT-systems will save a lot of work (and human errors), as the sensor readings will be directly recorded in the patient’s records by the sensors themselves, rather than by a transcription performed by a busy clinician. Although this development has been going on for at least...... a short while. This tension between simple use and security in a low-power clinical environment is the main theme of this dissertation. Un-secure medical equipment will never pass official certification by national health authorities, but on the other hand, experience shows that if using the equipment...

  8. Wireless Sensor Technologies and Applications

    Directory of Open Access Journals (Sweden)

    Feng Xia

    2009-11-01

    Full Text Available Recent years have witnessed tremendous advances in the design and applications of wirelessly networked and embedded sensors. Wireless sensor nodes are typically low-cost, low-power, small devices equipped with limited sensing, data processing and wireless communication capabilities, as well as power supplies. They leverage the concept of wireless sensor networks (WSNs, in which a large (possibly huge number of collaborative sensor nodes could be deployed. As an outcome of the convergence of micro-electro-mechanical systems (MEMS technology, wireless communications, and digital electronics, WSNs represent a significant improvement over traditional sensors. In fact, the rapid evolution of WSN technology has accelerated the development and deployment of various novel types of wireless sensors, e.g., multimedia sensors. Fulfilling Moore’s law, wireless sensors are becoming smaller and cheaper, and at the same time more powerful and ubiquitous. [...

  9. Nanomaterials and Chemical Sensors

    Directory of Open Access Journals (Sweden)

    Sukumar BASU

    2011-11-01

    Full Text Available Nanomaterials and nanosensors are two most important iconic words of the modern science & Technology. Though nano technology is relatively a new area of research & development it will soon be included in the most modern electronic circuitry used for advanced computing systems. Since it will provide the potential link between the nanotechnology and the macroscopic world the development is primarily directed towards exploitation of nanotechnology to computer chip miniaturization and vast storage capacity. However, for implementation in the consumer products the present high cost of production must be overcome. There are different ways to make nanosensors e.g. top-down lithography, bottom-up assembly, and self molecular assembly. Consequently, nanomaterials & nanosensors have to be made compatible with the consumer technologies. The progress in detecting and sensing different chemical species with increased accuracy may transform the human society from uncertainty and inaccuracy to more precise and definite world of information. For example, extremely low concentrations of air pollutants or toxic materials in air & water around us can be accurately and economically detected in no time to save the human beings from the serious illnesses. Also, the medical sensors will help in diagnoses of the diseases, their treatment and in predicting the future profile of the individual so that the health insurance companies may exploit the opportunity to grant or to deny the health coverage. Other social issues like privacy invasion and security may be best monitored by the widespread use of the surveillance devices using nanosensors.

  10. 3D-profile measurement of advanced semiconductor features by reference metrology

    Science.gov (United States)

    Takamasu, Kiyoshi; Iwaki, Yuuki; Takahashi, Satoru; Kawada, Hiroki; Ikota, Masami; Lorusso, Gian F.; Horiguchi, Naoto

    2016-03-01

    A method of sub-nanometer uncertainty for the 3D-profile measurement using TEM (Transmission Electron Microscope) images is proposed to standardize 3D-profile measurement through reference metrology. The proposed method has been validated for profiles of Si lines, photoresist features and advanced-FinFET (Fin-shaped Field-Effect Transistor) features in our previous investigations. However, efficiency of 3D-profile measurement using TEM is limited by measurement time including processing of the sample. In this article, we demonstrate a novel on-wafer 3D-profile metrology as "FIB-to-CDSEM method" with FIB (Focused Ion Beam) slope cut and CD-SEM (Critical Dimension Secondary Electron Microscope) measuring. Using the method, a few micrometer wide on a wafer is coated and cut by 45 degree slope using FIB tool. Then, the wafer is transferred to CD-SEM to measure the cross section image by top down CD-SEM measurement. We apply FIB-to-CDSEM method to CMOS sensor device. 3D-profile and 3D-profile parameters such as top line width and side wall angles of CMOS sensor device are evaluated. The 3D-profile parameters also are measured by TEM images as reference metrology. We compare the 3D-profile parameters by TEM method and FIB-to-CDSEM method. The average values and correlations on the wafer are agreed well between TEM and FIB-to- CDSEM methods.

  11. Have combustible cigarettes met their match? The nicotine delivery profiles and harmful constituent exposures of second-generation and third-generation electronic cigarette users.

    Science.gov (United States)

    Wagener, Theodore L; Floyd, Evan L; Stepanov, Irina; Driskill, Leslie M; Frank, Summer G; Meier, Ellen; Leavens, Eleanor L; Tackett, Alayna P; Molina, Neil; Queimado, Lurdes

    2017-03-01

    Electronic cigarettes' (e-cigarettes) viability as a public health strategy to end smoking will likely be determined by their ability to mimic the pharmacokinetic profile of a cigarette while also exposing users to significantly lower levels of harmful/potentially harmful constituents (HPHCs). The present study examined the nicotine delivery profile of third- (G3) versus second-generation (G2) e-cigarette devices and their users' exposure to nicotine and select HPHCs compared with cigarette smokers. 30 participants (10 smokers, 9 G2 and 11 G3 users) completed baseline questionnaires and provided exhaled carbon monoxide (eCO), saliva and urine samples. Following a 12-hour nicotine abstinence, G2 and G3 users completed a 2-hour vaping session (ie, 5 min, 10-puff bout followed by ad libitum puffing for 115 min). Blood samples, subjective effects, device characteristics and e-liquid consumption were assessed. Smokers, G2 and G3 users had similar baseline levels of cotinine, but smokers had 4 and 7 times higher levels of eCO (pe-cigarettes resulted in significantly lower levels of exposure to a potent lung carcinogen and cardiovascular toxicant. These findings have significant implications for understanding the addiction potential of these devices and their viability/suitability as aids to smoking cessation. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  12. CRED Acoustic Doppler Profiler (ADP); AMSM, ROS; Long: -168.15481, Lat: -14.53510 (WGS84); Sensor Depth: 7.01m; Data Range: 20080311-20080314.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Island Fisheries Science Center Acoustic Doppler Profilers (ADP) provide a time series of water current...

  13. CRED Acoustic Doppler Profiler (ADP); NWHI, MID; Long: -177.42181, Lat: 28.21826 (WGS84); Sensor Depth: 1.83m; Data Range: 20080926-20090321.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Island Fisheries Science Center Acoustic Doppler Profilers (ADP) provide a time series of water current...

  14. Effectiveness in cleaning oval-shaped root canals using Anatomic Endodontic Technology, ProFile and manual instrumentation: a scanning electron microscopic study.

    Science.gov (United States)

    Zmener, O; Pameijer, C H; Banegas, G

    2005-06-01

    To compare in vitro the cleanliness of root canal walls in oval-shaped root canals following automated or manual instrumentation. Forty-five oval-shaped single-rooted maxillary and mandibular premolars with straight canals were divided into three groups of 15. Automated canal preparation was performed using Anatomic Endodontic Technology (AET, group 1) and the ProFile system (group 2). Manual instrumentation (group 3) was performed with K-Flexofiles. Irrigation was performed using alternately 5.25% NaOCl and 17% EDTA, followed by rinsing with saline. The roots were split longitudinally into halves and the canals examined at x200 and x400 in a scanning electron microscope. The presence of debris and smear layer was recorded at distances of 1, 5 and 10 mm from the working length using a three-step scoring scale and a 300 mum square grid. Mean scores for debris and smear layer were calculated and statistically analysed for significance (P < 0.05) between and within groups, using the Kruskal-Wallis nonparametric anova and Dunn's tests. At 1, 5 and 10-mm levels the root canals prepared with AET had significantly less surface debris and smear layer on the canal walls compared with canals prepared with ProFile or manual instrumentation. For all three groups significantly lower mean smear layer scores (P < 0.05) were recorded at 5 and 10-mm levels compared with the 1 mm level. Significantly lower mean debris scores (P < 0.05) were also recorded at 5 and 10-mm levels for the AET group whereas no significant differences were found between the three levels for the ProFile and manual instrumentation groups. Although better instrumentation scores were obtained in canals prepared with AET, complete cleanliness was not achieved by any of the techniques and instruments investigated.

  15. Polysubstance use profiles among electronic dance music party attendees in New York City and their relation to use of new psychoactive substances.

    Science.gov (United States)

    Fernández-Calderón, Fermín; Cleland, Charles M; Palamar, Joseph J

    2018-03-01

    Electronic Dance Music (EDM) party attendees are often polysubstance users and are at high risk for use of new psychoactive substances (NPS). We sought to identify patterns of use of common illegal drugs among EDM party attendees, sociodemographic correlates, and use of NPS as a function of patterns of use of more common drugs to inform prevention and harm reduction. Using time-space-sampling, 1045 individuals aged 18-40 were surveyed entering EDM parties in New York City. We queried past-year use of common illegal drugs and 98 NPS. We conducted latent class analysis to identify polysubstance use profiles of use of eight common drugs (i.e., ecstasy, ketamine, LSD, mushrooms, powder cocaine, marijuana, amphetamine, benzodiazepines). Relationships between drug classification membership and sociodemographics and use of drugs within six NPS categories were examined. We identified four profiles of use of common drugs: non-polysubstance use (61.1%), extensive polysubstance use (19.2%), moderate polysubstance use/stimulants (12.8%), and moderate polysubstance use/psychedelics (6.7%). Those in the moderate/psychedelic group were at higher odds of using NPS with psychedelic-type effects (2C, tryptamines, and other "new" psychedelics; Ps<0.05). Extensive polysubstance users were at increased odds of reporting use of 2C drugs, synthetic cathinones ("bath salts"), tryptamines, other new (non-phenethylamine) psychedelics, new dissociatives, and synthetic cannabinoids (Ps<0.05). NPS preference is linked to the profile of use of common drugs among individuals in the EDM scene. Most participants were identified as non-polysubstance users, but findings may help inform preventive and harm reduction interventions among those at risk in this scene. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Comparison of intact Arabidopsis thaliana leaf transcript profiles during treatment with inhibitors of mitochondrial electron transport and TCA cycle.

    Directory of Open Access Journals (Sweden)

    Ann L Umbach

    Full Text Available Plant mitochondria signal to the nucleus leading to altered transcription of nuclear genes by a process called mitochondrial retrograde regulation (MRR. MRR is implicated in metabolic homeostasis and responses to stress conditions. Mitochondrial reactive oxygen species (mtROS are a MRR signaling component, but whether all MRR requires ROS is not established. Inhibition of the cytochrome respiratory pathway by antimycin A (AA or the TCA cycle by monofluoroacetate (MFA, each of which initiates MRR, can increase ROS production in some plant cells. We found that for AA and MFA applied to leaves of soil-grown Arabidopsis thaliana plants, ROS production increased with AA, but not with MFA, allowing comparison of transcript profiles under different ROS conditions during MRR. Variation in transcript accumulation over time for eight nuclear encoded mitochondrial protein genes suggested operation of both common and distinct signaling pathways between the two treatments. Consequences of mitochondrial perturbations for the whole transcriptome were examined by microarray analyses. Expression of 1316 and 606 genes was altered by AA and MFA, respectively. A subset of genes was similarly affected by both treatments, including genes encoding photosynthesis-related proteins. MFA treatment resulted in more down-regulation. Functional gene category (MapMan and cluster analyses showed that genes with expression levels affected by perturbation from AA or MFA inhibition were most similarly affected by biotic stresses such as pathogens. Overall, the data provide further evidence for the presence of mtROS-independent MRR signaling, and support the proposed involvement of MRR and mitochondrial function in plant responses to biotic stress.

  17. Ambient Sensors

    NARCIS (Netherlands)

    Börner, Dirk; Specht, Marcus

    2014-01-01

    This software sketches comprise two custom-built ambient sensors, i.e. a noise and a movement sensor. Both sensors measure an ambient value and process the values to a color gradient (green > yellow > red). The sensors were built using the Processing 1.5.1 development environment. Available under

  18. Transcriptional profiling of human breast cancer cells cultured under microgravity conditions revealed the key role of genetic gravity sensors previously detected in Drosophila melanogaster

    Science.gov (United States)

    Valdivia-Silva, Julio E.; Lavan, David; Diego Orihuela-Tacuri, M.; Sanabria, Gabriela

    2016-07-01

    Currently, studies in Drosophila melanogaster has shown emerging evidence that microgravity stimuli can be detected at the genetic level. Analysis of the transcriptome in the pupal stage of the fruit flies under microgravity conditions versus ground controls has suggested the presence of a few candidate genes as "gravity sensors" which are experimentally validated. Additionally, several studies have shown that microgravity causes inhibitory effects in different types of cancer cells, although the genes involved and responsible for these effects are still unknown. Here, we demonstrate that the genes suggested as the sensors of gravitational waves in Drosophila melanogaster and their human counterpart (orthologous genes) are highly involved in carcinogenesis, proliferation, anti-apoptotic signals, invasiveness, and metastatic potential of breast cancer cell tumors. The transcriptome analyses suggested that the observed inhibitory effect in cancer cells could be due to changes in the genetic expression of these candidates. These results encourage the possibility of new therapeutic targets managed together and not in isolation.

  19. Flexible Electronics: Theoretical and Experimental Studies of Epidermal Heat Flux Sensors for Measurements of Core Body Temperature (Adv. Healthcare Mater. 1/2016).

    Science.gov (United States)

    Zhang, Yihui; Chad Webb, Richard; Luo, Hongying; Xue, Yeguang; Kurniawan, Jonas; Cho, Nam Heon; Krishnan, Siddharth; Li, Yuhang; Huang, Yonggang; Rogers, John A

    2016-01-01

    On page 119, J. A. Rogers and co-workers present theoretical approaches, modeling algorithms, materials, and device designs for the noninvasive measurement of core body temperature by using multiple differential temperature sensors that attach softly and intimately onto the surface of the skin. The image shows the construction of differential temperature sensors using thermally insulating foam as the separation material. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Design and implementation of a generic energy-harvesting framework applied to the evaluation of a large-scale electronic shelf-labeling wireless sensor network

    OpenAIRE

    Kamerman Ad; De Mil Pieter; Jooris Bart; Tytgat Lieven; Catteeuw Ruben; Moerman Ingrid; Demeester Piet

    2010-01-01

    Most wireless sensor networks (WSNs) consist of battery-powered nodes and are limited to hundreds of nodes. Battery replacement is a very costly operation and a key factor in limiting successful large-scale deployments. The recent advances in both energy harvesters and low-power communication systems hold promise for deploying large-scale wireless green-powered sensor networks (WGSNs). This will enable new applications and will eliminate environmentally unfriendly battery disposal. This pape...

  1. Simultaneous in situ characterisation of bubble dynamics and a spatially resolved concentration profile: a combined Mach–Zehnder holography and confocal Raman-spectroscopy sensor system

    Directory of Open Access Journals (Sweden)

    J. Guhathakurta

    2017-05-01

    Full Text Available For a reaction between a gaseous phase and a liquid phase, the interaction between the hydrodynamic conditions, mass transport and reaction kinetics plays a crucial role with respect to the conversion and selectivity of the process. Within this work, a sensor system was developed to simultaneously characterise the bubble dynamics and the localised concentration measurement around the bubbles. The sensor system is a combination of a digital Mach–Zehnder holography subsystem to measure bubble dynamics and a confocal Raman-spectroscopy subsystem to measure localised concentration. The combined system was used to investigate the chemical absorption of CO2 bubbles in caustic soda in microchannels. The proposed set-up is explained and characterised in detail and the experimental results are presented, illustrating the capability of the sensor system to simultaneously measure the localised concentration of the carbonate ion with a good limit of detection and the 3-D position of the bubble with respect to the spot where the concentration was measured.

  2. Smart and Intelligent Sensors

    Science.gov (United States)

    Lansaw, John; Schmalzel, John; Figueroa, Jorge

    2009-01-01

    John C. Stennis Space Center (SSC) provides rocket engine propulsion testing for NASA's space programs. Since the development of the Space Shuttle, every Space Shuttle Main Engine (SSME) has undergone acceptance testing at SSC before going to Kennedy Space Center (KSC) for integration into the Space Shuttle. The SSME is a large cryogenic rocket engine that uses Liquid Hydrogen (LH2) as the fuel. As NASA moves to the new ARES V launch system, the main engines on the new vehicle, as well as the upper stage engine, are currently base lined to be cryogenic rocket engines that will also use LH2. The main rocket engines for the ARES V will be larger than the SSME, while the upper stage engine will be approximately half that size. As a result, significant quantities of hydrogen will be required during the development, testing, and operation of these rocket engines.Better approaches are needed to simplify sensor integration and help reduce life-cycle costs. 1.Smarter sensors. Sensor integration should be a matter of "plug-and-play" making sensors easier to add to a system. Sensors that implement new standards can help address this problem; for example, IEEE STD 1451.4 defines transducer electronic data sheet (TEDS) templates for commonly used sensors such as bridge elements and thermocouples. When a 1451.4 compliant smart sensor is connected to a system that can read the TEDS memory, all information needed to configure the data acquisition system can be uploaded. This reduces the amount of labor required and helps minimize configuration errors. 2.Intelligent sensors. Data received from a sensor be scaled, linearized; and converted to engineering units. Methods to reduce sensor processing overhead at the application node are needed. Smart sensors using low-cost microprocessors with integral data acquisition and communication support offer the means to add these capabilities. Once a processor is embedded, other features can be added; for example, intelligent sensors can make

  3. In Vitro Dosing Performance of the ELLIPTA® Dry Powder Inhaler Using Asthma and COPD Patient Inhalation Profiles Replicated with the Electronic Lung (eLung™).

    Science.gov (United States)

    Hamilton, Melanie; Leggett, Richard; Pang, Cheng; Charles, Stephen; Gillett, Ben; Prime, David

    2015-12-01

    To evaluate the in vitro dose delivery characteristics of approved asthma and chronic obstructive pulmonary disease (COPD) therapies delivered via the ELLIPTA(®) dry powder inhaler across inhalation endpoints representative of the target patient population, using the Electronic Lung (eLung™) to replicate inhaler-specific patient inhalation profiles that were previously recorded in vivo. Selected profiles, representative of the range of inhalation endpoints achieved by patients with all severities of asthma and COPD, were replicated using the eLung breathing simulator in conjunction with an oropharyngeal cast. A Next Generation Impactor was coupled to the eLung to determine the aerodynamic particle size distribution of the ex-throat dose (ETD) of asthma and COPD therapies delivered via the ELLIPTA inhaler. Delivered dose (DD), ETD, and fine particle dose (FPD; defined as a mass of active substance less than 5 μm) were determined for fluticasone furoate (FF)/vilanterol (VI) 100/25 μg and 200/25 μg (asthma and COPD), umeclidinium (UMEC)/VI 62.5/25 μg (COPD only), FF 100 μg and 200μg monotherapy (asthma only), and UMEC 62.5 μg monotherapy (COPD only). Inhalation profiles replicated by eLung covered a wide range of peak inspiratory flow rates (41.6-136.9 L/min), pressure drops (1.2-13.8 kPa), and inhaled volumes through the inhaler (0.7-4.2L). DD was consistent across the range of patient representative inhalation parameters for all components (FF, VI, and UMEC) of each therapy assessed; although ETD and FPD were also generally consistent, some small variation was observed. Dose delivery was consistent for each of the components, whether delivered as mono- or combination therapy. The in vitro performance of the ELLIPTA inhaler has been demonstrated for the delivery of FF/VI, UMEC/VI, FF monotherapy, and UMEC monotherapy. Across a range of inspiratory profiles, DD was consistent, while ETD and FPD showed little flow dependency.

  4. In Vitro Dosing Performance of the ELLIPTA® Dry Powder Inhaler Using Asthma and COPD Patient Inhalation Profiles Replicated with the Electronic Lung (eLung™)

    Science.gov (United States)

    Leggett, Richard; Pang, Cheng; Charles, Stephen; Gillett, Ben; Prime, David

    2015-01-01

    Abstract Background: To evaluate the in vitro dose delivery characteristics of approved asthma and chronic obstructive pulmonary disease (COPD) therapies delivered via the ELLIPTA® dry powder inhaler across inhalation endpoints representative of the target patient population, using the Electronic Lung (eLung™) to replicate inhaler-specific patient inhalation profiles that were previously recorded in vivo. Methods: Selected profiles, representative of the range of inhalation endpoints achieved by patients with all severities of asthma and COPD, were replicated using the eLung breathing simulator in conjunction with an oropharyngeal cast. A Next Generation Impactor was coupled to the eLung to determine the aerodynamic particle size distribution of the ex-throat dose (ETD) of asthma and COPD therapies delivered via the ELLIPTA inhaler. Delivered dose (DD), ETD, and fine particle dose (FPD; defined as a mass of active substance less than 5 μm) were determined for fluticasone furoate (FF)/vilanterol (VI) 100/25 μg and 200/25 μg (asthma and COPD), umeclidinium (UMEC)/VI 62.5/25 μg (COPD only), FF 100 μg and 200μg monotherapy (asthma only), and UMEC 62.5 μg monotherapy (COPD only). Results: Inhalation profiles replicated by eLung covered a wide range of peak inspiratory flow rates (41.6–136.9 L/min), pressure drops (1.2–13.8 kPa), and inhaled volumes through the inhaler (0.7–4.2L). DD was consistent across the range of patient representative inhalation parameters for all components (FF, VI, and UMEC) of each therapy assessed; although ETD and FPD were also generally consistent, some small variation was observed. Dose delivery was consistent for each of the components, whether delivered as mono- or combination therapy. Conclusions: The in vitro performance of the ELLIPTA inhaler has been demonstrated for the delivery of FF/VI, UMEC/VI, FF monotherapy, and UMEC monotherapy. Across a range of inspiratory profiles, DD was consistent, while ETD

  5. Electronics and Telemetry Engineering and Test Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Electronics Laboratory is a fully equipped facility providing the capability to support electronic product development from highly complex weapon system sensors,...

  6. Stretchable electronics

    CERN Document Server

    Someya, Takao

    2012-01-01

    With its comprehensive coverage this handbook and ready reference brings together some of the most outstanding scientists in the field to lay down the undisputed knowledge on how to make electronics stretchable.As such, it focuses on gathering and evaluating the materials, designs, models and technologies that enable the fabrication of fully elastic electronic devices which can sustain high strain. Furthermore, it provides a review of those specific applications that directly benefit from highly compliant electronics, including transistors, photonic devices and sensors. In addition to stre

  7. Using spread spectrum for AMR magnetic sensor

    Science.gov (United States)

    Vala, David

    2016-09-01

    This contribution describe invention of Magnetometer with protection against detection by electronic counter- measure (ECM) registered by Czech patent office as patent no. 305322.1 Magnetic sensors are often part of dual use or security instruments and equipment. For this purpose is very interesting to build sensor with is hidden against electronic countermeasure. In this case is very important level and behavior of electromagnetic noise produced by sensor. And also electromagnetic compatibility of electronic devices is the area which significant grows nowadays too. As the consequence of this growth there is a continuous process of making more strict standards focused on electromagnetic radiation of electronic devices. Sensors technology begins to be a part of these issues due sensors bandwidth increasing and approaching to frequency of radio communication band. Nowadays microcontrollers and similar digital circuits are integrated into sensors devices and it brings new sources of electromagnetic radiation in modern smart sensors.

  8. Quantifying water flow within aquatic ecosystems using load cell sensors: a profile of currents experienced by coral reef organisms around Lizard Island, Great Barrier Reef, Australia.

    Science.gov (United States)

    Johansen, Jacob L

    2014-01-01

    Current velocity in aquatic environments has major implications for the diversity, abundance and ecology of aquatic organisms, but quantifying these currents has proven difficult. This study utilises a simple and inexpensive instrument (reef system around Lizard Island (Great Barrier Reef, Australia) at a spatial and temporal scale relevant to the ecology of individual benthos and fish. The instrument uses load-cell sensors to provide a correlation between sensor output and ambient current velocity of 99%. Each instrument is able to continuously record current velocities to >500 cms⁻¹ and wave frequency to >100 Hz over several weeks. Sensor data are registered and processed at 16 MHz and 10 bit resolution, with a measuring precision of 0.06±0.04%, and accuracy of 0.51±0.65% (mean ±S.D.). Each instrument is also pressure rated to 120 m and shear stresses ≤20 kNm⁻² allowing deployment in harsh environments. The instrument was deployed across 27 coral reef sites covering the crest (3 m), mid-slope (6 m) and deep-slope (9 m depth) of habitats directly exposed, oblique or sheltered from prevailing winds. Measurements demonstrate that currents over the reef slope and crest varies immensely depending on depth and exposure: currents differ up to 9-fold within habitats only separated by 3 m depth and 15-fold between exposed, oblique and sheltered habitats. Comparisons to ambient weather conditions reveal that currents around Lizard Island are largely wind driven. Zero to 22.5 knot winds correspond directly to currents of 0 to >82 cms⁻¹, while tidal currents rarely exceed 5.5 cms⁻¹. Rather, current velocity increases exponentially as a function of wave height (0 to 1.6 m) and frequency (0.54 to 0.20 Hz), emphasizing the enormous effect of wind and waves on organisms in these shallow coral reef habitats.

  9. Compton profile of tantalum

    Indian Academy of Sciences (India)

    scale-Compton profile is directly related to the momentum distribution of the electrons. The spectral analysis ... proximation, the Compton profile J(q) is the projection of the target's electron momentum distribution, n(p) ... densed matter and serves as a reliable test of the accuracy of the calculated wave functions. Such basic ...

  10. Environmental exposure tracking sensor

    Science.gov (United States)

    Havens, Teresa; Everhart, Joel; McFerran, Jace

    2009-03-01

    Cornerstone Research Group Inc. (CRG) has developed environmental exposure tracking (EET) sensors using shape memory polymer (SMP) to monitor the degradation of perishable items, such as munitions, medicines or foods, by measuring the cumulative exposure to temperature and moisture. SMPs are polymers whose qualities have been altered to give them dynamic shape "memory" properties. Under thermal or moisture stimuli, SMP exhibits a radical change from a rigid thermoset to a highly flexible, elastic state. The dynamic response of the SMP can be tailored to match the degradation profile of the perishable item. SMP-based EET sensors require no digital memory or internal power supply and provide the capability of inexpensive, long-term life cycle monitoring thermal and moisture exposure over time. In a Phase I and II SBIR effort with the Navy, CRG demonstrated the feasibility of SMP-based EET sensor with two material systems. These material systems required different activation stimuli, heat or water vapor pressure. CRG developed the ability to tailor these materials to customize the dynamic response to match various degradation profiles of munitions. CRG optimized and characterized the SMP formulations and sensor design configuration to develop a suite of data from which any degradation profile can be met. CRG's EET sensors are capable of monitoring temperatures from -30 °C to 260 °C. The prototypes monitor cumulative thermal exposure and provide real-time information in a visually readable or a remotely interrogated version. CRG is currently scaling up the manufacture of the sensors for munitions reliability applications with the Navy.

  11. Method for Operating a Sensor to Differentiate Between Analytes in a Sample

    Science.gov (United States)

    Kunt, Tekin; Cavicchi, Richard E; Semancik, Stephen; McAvoy, Thomas J

    1998-07-28

    Disclosed is a method for operating a sensor to differentiate between first and second analytes in a sample. The method comprises the steps of determining a input profile for the sensor which will enhance the difference in the output profiles of the sensor as between the first analyte and the second analyte; determining a first analyte output profile as observed when the input profile is applied to the sensor; determining a second analyte output profile as observed when the temperature profile is applied to the sensor; introducing the sensor to the sample while applying the temperature profile to the sensor, thereby obtaining a sample output profile; and evaluating the sample output profile as against the first and second analyte output profiles to thereby determine which of the analytes is present in the sample.

  12. Discrimination of Xihulongjing tea grade using an electronic tongue

    African Journals Online (AJOL)

    STORAGESEVER

    2009-12-15

    position autosampler and associated interface electronic module. The sensors were based on an innovative electrochemical potentiometric sensor technology: the Chemical Modified Field-. Effect-Transistor (CHEMFET) technology.

  13. Flexible magnetoimpidence sensor

    KAUST Repository

    Kavaldzhiev, Mincho

    2015-05-01

    Recently, flexible electronic devices have attracted increasing interest, due to the opportunities they promise for new applications such as wearable devices, where the components are required to flex during normal use[1]. In this light, different magnetic sensors, like microcoil, spin valve, giant magnetoresistance (GMR), magnetoimpedance (MI), have been studied previously on flexible substrates.

  14. Metamaterial Sensors

    Directory of Open Access Journals (Sweden)

    Jing Jing Yang

    2013-01-01

    Full Text Available Metamaterials have attracted a great deal of attention due to their intriguing properties, as well as the large potential applications for designing functional devices. In this paper, we review the current status of metamaterial sensors, with an emphasis on the evanescent wave amplification and the accompanying local field enhancement characteristics. Examples of the sensors are given to illustrate the principle and the performance of the metamaterial sensor. The paper concludes with an optimistic outlook regarding the future of metamaterial sensor.

  15. Real time failure detection in unreinforced cementitious composites with triboluminescent sensor

    Energy Technology Data Exchange (ETDEWEB)

    Olawale, David O. [High-Performance Materials Institute, Department of Industrial Engineering, FAMU-FSU College of Engineering, 2525 Pottsdamer Street, Tallahassee, FL 32310 (United States); Nanotechnology Patronas Group Inc., Tallahassee, FL 32311 (United States); Kliewer, Kaitlyn [High-Performance Materials Institute, Department of Industrial Engineering, FAMU-FSU College of Engineering, 2525 Pottsdamer Street, Tallahassee, FL 32310 (United States); Okoye, Annuli [Department of Chemical Engineering, University of Massachusetts at Amherst, 686 North Pleasant Street, 159 Goessmann Laboratory, Amherst, MA 01003 (United States); Dickens, Tarik J. [High-Performance Materials Institute, Department of Industrial Engineering, FAMU-FSU College of Engineering, 2525 Pottsdamer Street, Tallahassee, FL 32310 (United States); Nanotechnology Patronas Group Inc., Tallahassee, FL 32311 (United States); Uddin, Mohammed J. [High-Performance Materials Institute, Department of Industrial Engineering, FAMU-FSU College of Engineering, 2525 Pottsdamer Street, Tallahassee, FL 32310 (United States); Okoli, Okenwa I., E-mail: okoli@eng.fsu.edu [High-Performance Materials Institute, Department of Industrial Engineering, FAMU-FSU College of Engineering, 2525 Pottsdamer Street, Tallahassee, FL 32310 (United States)

    2014-03-15

    The in-situ triboluminescent optical fiber (ITOF) sensor has an integrated sensing and transmission component that converts the energy from damage events like impacts and crack propagation into optical signals that are indicative of the magnitude of damage in composite structures like concrete bridges. Utilizing the triboluminescence (TL) property of ZnS:Mn, the ITOF sensor has been successfully integrated into unreinforced cementitious composite beams to create multifunctional smart structures with in-situ failure detection capabilities. The fabricated beams were tested under flexural loading, and real time failure detection was made by monitoring the TL signals generated by the integrated ITOF sensor. Tested beam samples emitted distinctive TL signals at the instance of failure. In addition, we report herein a new and promising approach to damage characterization using TL emission profiles. Analysis of TL emission profiles indicates that the ITOF sensor responds to crack propagation through the beam even when not in contact with the crack. Scanning electron microscopy analysis indicated that fracto-triboluminescence was responsible for the TL signals observed at the instance of beam failure. -- Highlights: • Developed a new approach to triboluminescence (TL)-based sensing with ZnS:Mn. • Damage-induced excitation of ZnS:Mn enabled real time damage detection in composite. • Based on sensor position, correlation exists between TL signal and failure stress. • Introduced a new approach to damage characterization with TL profile analysis.

  16. Sensor networks

    NARCIS (Netherlands)

    Chatterjea, Supriyo; Thurston, J.; Kininmonth, S.; Havinga, Paul J.M.

    2006-01-01

    This article describes the details of a sensor network that is currently being deployed at the Great Barrier Reef in Australia. The sensor network allows scientists to retrieve sensor data that has a high spatial and temporal resolution. We give an overview of the energy-efficient data aggregation

  17. Attention Sensor

    NARCIS (Netherlands)

    Börner, Dirk; Kalz, Marco; Specht, Marcus

    2014-01-01

    This software sketch was used in the context of an experiment for the PhD project “Ambient Learning Displays”. The sketch comprises a custom-built attention sensor. The sensor measured (during the experiment) whether a participant looked at and thus attended a public display. The sensor was built

  18. Photon-counting image sensors

    CERN Document Server

    Teranishi, Nobukazu; Theuwissen, Albert; Stoppa, David; Charbon, Edoardo

    2017-01-01

    The field of photon-counting image sensors is advancing rapidly with the development of various solid-state image sensor technologies including single photon avalanche detectors (SPADs) and deep-sub-electron read noise CMOS image sensor pixels. This foundational platform technology will enable opportunities for new imaging modalities and instrumentation for science and industry, as well as new consumer applications. Papers discussing various photon-counting image sensor technologies and selected new applications are presented in this all-invited Special Issue.

  19. Advanced Magnetoimpedance Sensors

    KAUST Repository

    Li, Bodong

    2015-02-01

    This thesis is concerned with the advanced topics of thin film magnetoimpedance (MI) sensors. The author proposes and develops novel MI sensors that target on the challenges arising from emerging applications such as flexible electronics, passive wireless sensing, etc. In the study of flexible MI sensor, the investigated sensors of NiFe/Cu/NiFe tri-layersare fabricated on three flexible substrates having different surface roughness: Kapton, standard and premiumphotopaper. Sensitivity versus substrate roughness analysis is carried out for the selection of optimal substrate material. The high magnetic sensing performance is achieved by using Kapton substrate. Stress simulation, incorporated with the theory of magnetostriction effect, reveals the material composition of Ni/Fe being as a key factor of the stress dependent MI effect for the flexible MI sensors. In the development of MI-SAW device for passive wireless magnetic field sensing, NiFe/Cu/NiFe tri-layersand interdigital transducers(IDT) are designed and fabricated on a single piece of LiNbO3substrate, providing a high degree of integration and the advantage of standard microfabrication. The double-electrodeIDT has been utilized and proven to have an optimal sensing performance in comparison to the bi-directional IDT design. The optimized high frequency performance of the thin film MI sensor results in a MI-SAW passive wireless magnetic sensor with high magnetic sensitivity comparing to the MI microwire approach. Benefiting from the high degree of integration of the MI thin film element, in the following study, two additional sensing elements are integrated to the SAW device to have a multifunctional passive wireless sensor with extended temperature and humidity sensing capabilities. Analytical models havebeen developed to eliminate the crossovers of different sensing signals through additional reference IDTs, resulting in a multifunctional passive wireless sensor with the capability of detecting all three

  20. Simulations of Gaussian electron guns for RHIC electron lens

    Energy Technology Data Exchange (ETDEWEB)

    Pikin, A. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.

    2014-02-28

    Simulations of two versions of the electron gun for RHIC electron lens are presented. The electron guns have to generate an electron beam with Gaussian radial profile of the electron beam density. To achieve the Gaussian electron emission profile on the cathode we used a combination of the gun electrodes and shaping of the cathode surface. Dependence of electron gun performance parameters on the geometry of electrodes and the margins for electrodes positioning are presented.

  1. In Situ Diagnostic Sensors for Thermal Protection Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Low-profile, embedded sensors are proposed for condition monitoring and health management (HM) of thermal protection systems. The sensors will be fabricated using a...

  2. Quorum sensing signal profile of Acinetobacter strains from nosocomial and environmental sources Perfil de sensores de quórum en cepas nosocomiales y ambientales de Acinetobacter

    Directory of Open Access Journals (Sweden)

    R. H. González

    2009-06-01

    Full Text Available A set of 43 strains corresponding to 20 classified and unclassified genomic Acinetobacter species was analyzed for the production of typical N-acyl homoserine lactone quorum sensing molecules in culture broths. A large percentage of the strains (74% displayed quorum sensing signals that could be separated into three statistically significantly different chromatographic groups (p Rf2 > Rf1. None of the three signals could be specifically assigned to a particular species in the genus; furthermore, no distinction could be made between the quorum sensing signals secreted by typical opportunistic strains of the A. calcoaceticus-A. baumannii complex, isolated from patients, with respect to the other species of the genus, except for the Rf1 signal which was present in all the QS positive strains belonging to this complex and DNA group 13 TU. In conclusion, quorum sensors in Acinetobacter are not homogenously distributed among species and one of them is present in most of the A. calcoaceticus-baumannii complex.Se analizó la producción de moléculas típicas de N-acil homoserina lactona con actividad de quorum sensing en cultivos líquidos de un grupo de 43 cepas correspondientes a 20 especies genómicas clasificadas y no clasificadas de Acinetobacter. Un porcentaje alto de las cepas (74% mostraron señales de quorum sensing que pudieron ser separadas en tres grupos cromatográficos significativamente diferentes entre sí (p Rf2 > Rf1. Ninguna de las tres señales pudo ser asignada a una especie en particular dentro del género; es más, no se encontró diferencia entre las señales producidas por las cepas típicamente oportunistas (complejo A. calcoaceticus-A. baumannii aisladas de pacientes respecto de las producidas por otras cepas del mismo género, excepto para el caso de Rf1, que se encontró presente en todos los aislamientos quorum sensing positivos del mencionado complejo y en las cepas del grupo de DNA 13TU. En conclusión, los sensores de

  3. Have combustible cigarettes met their match? The nicotine delivery profiles and harmful constituent exposures of second-generation and third-generation electronic cigarette users

    Science.gov (United States)

    Wagener, Theodore L; Floyd, Evan L; Stepanov, Irina; Driskill, Leslie M; Frank, Summer G; Meier, Ellen; Leavens, Eleanor L; Tackett, Alayna P; Molina, Neil; Queimado, Lurdes

    2017-01-01

    Introduction Electronic cigarettes’ (e-cigarettes) viability as a public health strategy to end smoking will likely be determined by their ability to mimic the pharmacokinetic profile of a cigarette while also exposing users to significantly lower levels of harmful/potentially harmful constituents (HPHCs). The present study examined the nicotine delivery profile of third- (G3) versus second-generation (G2) e-cigarette devices and their users’ exposure to nicotine and select HPHCs compared with cigarette smokers. Methods 30 participants (10 smokers, 9 G2 and 11 G3 users) completed baseline questionnaires and provided exhaled carbon monoxide (eCO), saliva and urine samples. Following a 12-hour nicotine abstinence, G2 and G3 users completed a 2-hour vaping session (ie, 5 min, 10-puff bout followed by ad libitum puffing for 115 min). Blood samples, subjective effects, device characteristics and e-liquid consumption were assessed. Results Smokers, G2 and G3 users had similar baseline levels of cotinine, but smokers had 4 and 7 times higher levels of eCO (pvaped e-cigarette liquids with significantly lower nicotine concentrations. During the vaping session, G3 users achieved significantly higher plasma nicotine concentrations than G2 users following the first 10 puffs (17.5 vs 7.3 ng/mL, respectively) and at 25 and 40 min of ad libitum use. G3 users consumed significantly more e-liquid than G2 users. Vaping urges/withdrawal were reduced following 10 puffs, with no significant differences between device groups. Discussion Under normal use conditions, both G2 and G3 devices deliver cigarette-like amounts of nicotine, but G3 devices matched the amount and speed of nicotine delivery of a conventional cigarette. Compared with cigarettes, G2 and G3 e-cigarettes resulted in significantly lower levels of exposure to a potent lung carcinogen and cardiovascular toxicant. These findings have significant implications for understanding the addiction potential of these devices and

  4. Fluorescent materials for pH sensing and imaging based on novel 1,4-diketopyrrolo-[3,4-c]pyrrole dyes†Electronic supplementary information (ESI) available: NMR and MS spectra, further sensor characteristics and sensor long-time performance. See DOI: 10.1039/c3tc31130aClick here for additional data file.

    Science.gov (United States)

    Aigner, Daniel; Ungerböck, Birgit; Mayr, Torsten; Saf, Robert; Klimant, Ingo; Borisov, Sergey M

    2013-09-28

    New optical pH-sensors relying on 1,4-diketopyrrolo-[3,4-c]pyrroles (DPPs) as fluorescent pH-indicators are presented. Different polymer hydrogels are useful as immobilization matrices, achieving excellent sensitivity and good brightness in the resulting sensor. The operational pH can be tuned over a wide range (pH 5-12) by selecting the fine structure of the indicator and the matrix. A ratiometric sensor in the form of nanoparticles is also presented. It is suitable for RGB camera readout, and its practical applicability for fluorescence imaging in microfluidic systems is demonstrated. The indicators are synthesized starting from the commercially available DPP pigments by a straightforward concept employing chlorosulfonation and subsequent reaction with amines. Their sensitivity derives from two distinct mechanisms. At high pH (>9), they exhibit a remarkable alteration of both absorption and fluorescence spectra due to deprotonation of the lactam nitrogen atoms. If a phenolic group is introduced, highly effective fluorescence quenching at near-neutral pH occurs due to photoinduced electron transfer (PET) involving the phenolate form.

  5. Biodegradable Piezoelectric Force Sensor.

    Science.gov (United States)

    Curry, Eli J; Ke, Kai; Chorsi, Meysam T; Wrobel, Kinga S; Miller, Albert N; Patel, Avi; Kim, Insoo; Feng, Jianlin; Yue, Lixia; Wu, Qian; Kuo, Chia-Ling; Lo, Kevin W-H; Laurencin, Cato T; Ilies, Horea; Purohit, Prashant K; Nguyen, Thanh D

    2018-01-30

    Measuring vital physiological pressures is important for monitoring health status, preventing the buildup of dangerous internal forces in impaired organs, and enabling novel approaches of using mechanical stimulation for tissue regeneration. Pressure sensors are often required to be implanted and directly integrated with native soft biological systems. Therefore, the devices should be flexible and at the same time biodegradable to avoid invasive removal surgery that can damage directly interfaced tissues. Despite recent achievements in degradable electronic devices, there is still a tremendous need to develop a force sensor which only relies on safe medical materials and requires no complex fabrication process to provide accurate information on important biophysiological forces. Here, we present a strategy for material processing, electromechanical analysis, device fabrication, and assessment of a piezoelectric Poly-l-lactide (PLLA) polymer to create a biodegradable, biocompatible piezoelectric force sensor, which only employs medical materials used commonly in Food and Drug Administration-approved implants, for the monitoring of biological forces. We show the sensor can precisely measure pressures in a wide range of 0-18 kPa and sustain a reliable performance for a period of 4 d in an aqueous environment. We also demonstrate this PLLA piezoelectric sensor can be implanted inside the abdominal cavity of a mouse to monitor the pressure of diaphragmatic contraction. This piezoelectric sensor offers an appealing alternative to present biodegradable electronic devices for the monitoring of intraorgan pressures. The sensor can be integrated with tissues and organs, forming self-sensing bionic systems to enable many exciting applications in regenerative medicine, drug delivery, and medical devices.

  6. Concentrations, profiles, and estimated human exposures for polychlorinated dibenzo-p-dioxins and dibenzofurans from electronic waste recycling facilities and a chemical industrial complex in Eastern China.

    Science.gov (United States)

    Ma, Jing; Kannan, Kurunthachalam; Cheng, Jinping; Horii, Yuichi; Wu, Qian; Wang, Wenhua

    2008-11-15

    Environmental pollution arising from electronic waste (e-waste) disposal and recycling has received considerable attention in recent years. Treatment, at low temperatures, of e-wastes that contain polyvinylchloride and related polymers can release polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Although several studies have reported trace metals and polybrominated diphenyl ethers (PBDEs) released from e-waste recycling operations, environmental contamination and human exposure to PCDD/Fs from e-waste recycling operations are less well understood. In this study, electronic shredder waste and dust from e-waste facilities, and leaves and surface soil collected in the vicinity of a large scale e-waste recycling facility in Taizhou, Eastern China, were analyzed for total PCDD/ Fs including 2,3,7,8-substituted congeners. We also determined PCDD/Fs in surface agricultural soils from several provinces in China for comparison with soils from e-waste facilities. Concentrations of total PCDD/Fs were high in all of the matrices analyzed and ranged from 30.9 to 11400 pg/g for shredder waste, 3460 to 9820 pg/g dry weight for leaves, 2560 to 148000 pg/g dry weight for workshop-floor dust, and 854 to 10200 pg/g dry weight for soils. We also analyzed surface soils from a chemical industrial complex (a coke-oven plant, a coal-fired power plant, and a chlor-alkali plant) in Shanghai. Concentrations of total PCDD/Fs in surface soil (44.5-531 pg/g dry wt) from the chemical industrial complex were lower than the concentrations found in soils from e-waste recycling plants, but higher than the concentrations found in agricultural soils. Agricultural soils from six cities in China contained low levels (3.44-33.8 pg/g dry wt) of total PCDD/Fs. Profiles of dioxin toxic equivalents (TEQs) of 2,3,7,8-PCDD/Fs in soils from e-waste facilities in Taizhou differed from the profiles found in agricultural soils. The estimated daily intakes of TEQs of PCDD/ Fs via soil/dust ingestion

  7. Smart sensors

    Science.gov (United States)

    Corsi, Carlo

    2006-08-01

    The term "Smart Sensors" refer to sensors which contain both sensing and signal processing capabilities with objectives ranging from simple viewing to sophisticated remote sensing, surveillance, search/track, weapon guidance, robotics, perceptronics and intelligence applications. In a broad sense, they include any sensor systems covering the whole electromagnetic spectrum: this paper deals specifically with a new class of smart sensors in infrared spectral bands whose developments started some years ago, when it was recognized that the rapid advances of "very large scale integration" (VLSI) processor technology and mosaic infrared detector array technology could be combined to develop new generations of infrared smart sensor systems with much improved performance. So, sophisticated signal processing operations have been developed for these new systems by integrating microcomputers and other VLSI signal processors within or next to the sensor arrays on the same focal plane avoiding complex computing located far away from the sensors. Recently this approach is achieving higher goals by a new and revolutionary sensors concept which introduce inside the sensor some of the basic function of living eyes, such as dynamic stare, dishomogenity compensation, spatial and temporal filtering. New objectives and requirements of these new focal plane processors are presented for this type of new infrared smart sensor systems. This paper is concerned with the processing techniques for only the front end of the focal plane processing, namely, the enhancement of target-to-noise ratio by background clutter suppression and the improvement in target detection by "smart" and pattern correlation threshold.

  8. Single electron-ics with carbon nanotubes

    NARCIS (Netherlands)

    Götz, G.T.J.

    2010-01-01

    We experimentally investigate Quantum Dots, formed in Carbon Nanotubes. The first part of this thesis deals with charge sensing on such quantum dots. The charge sensor is a metallic Single-electron-transistor, sensitive to the charge of a single electron on the quantum dot. We use this technique for

  9. Application of Thomson scattering at 1.06{mu}m as a diagnostic for spatial profile measurements of electron temperature and density on the TCV tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Franke, S. [Ecole Polytechnique Federale, Lausanne (Switzerland). Centre de Recherche en Physique des Plasma (CRPP)

    1997-04-01

    The variable configuration tokamak, TCV, in operation at CRPP since the end of 1991, is a particularly challenging machine with regard to the experimental system that must provide essential information regarding properties of confined plasmas with strongly shaped, non-circular cross-sections. The importance of the energy confinement issue in a machine designed specifically for the investigation of the effect of plasma shape on confinement and stability is self-evident, as is the necessity for a diagnostic capable of providing the profiles of electron temperature and density required for evaluation of this confinement. For TCV, a comprehensive Thomson Scattering (TS) diagnostic was the natural choice, specifically owing to the resulting spatially localized and time resolved measurement. The details of the system installed on TCV, together with the results obtained from the diagnostic comprise the subject matter of this thesis. A first version of the diagnostic was equipped with only ten observation volumes. In this case, adequate spatial resolution can only be maintained if measurements are limited to plasmas located in the upper half of the highly elongated TCV vacuum vessel. The system has recently been upgraded through the addition of a further fifteen observation volumes, together with major technical improvements in the scattered light detection system. This new version now permits TS observations in all TCV plasma configurations, including equilibria produced in the lower and upper halves of the vacuum vessel and the highly elongated plasmas now routinely created. Whilst a description of the new detection system along with some results obtained using the extended set of observation volumes are included, this thesis reports principally on the hardware details of and the interpretation of data from the original, ten observation volume system. (author) figs., tabs., 75 refs.

  10. Photoionization microplasma sensor

    Science.gov (United States)

    Mustafaev, A. S.; Rastvorova, I. V.; Podenko, S. S.; Tsyganov, A. B.

    2017-11-01

    New developments in the physics of plasma are presented, specifically, research of completely new method of atoms’ and molecules’ detection in gaseous phase – collisional electron spectroscopy. As a result, the microplasma sensor for quality and quantity analysis of the gaseous mixture was created. It works in the discharge afterglow mode using He as a buffer gas. In addition, the modification of the sensor using resonance photon photoionization was developed. This consideration gives the opportunity for wide practical appliance as an individual gas analyzer for industrial and medical purposes.

  11. Quantifying water flow within aquatic ecosystems using load cell sensors: a profile of currents experienced by coral reef organisms around Lizard Island, Great Barrier Reef, Australia.

    Directory of Open Access Journals (Sweden)

    Jacob L Johansen

    Full Text Available Current velocity in aquatic environments has major implications for the diversity, abundance and ecology of aquatic organisms, but quantifying these currents has proven difficult. This study utilises a simple and inexpensive instrument (500 cms⁻¹ and wave frequency to >100 Hz over several weeks. Sensor data are registered and processed at 16 MHz and 10 bit resolution, with a measuring precision of 0.06±0.04%, and accuracy of 0.51±0.65% (mean ±S.D.. Each instrument is also pressure rated to 120 m and shear stresses ≤20 kNm⁻² allowing deployment in harsh environments. The instrument was deployed across 27 coral reef sites covering the crest (3 m, mid-slope (6 m and deep-slope (9 m depth of habitats directly exposed, oblique or sheltered from prevailing winds. Measurements demonstrate that currents over the reef slope and crest varies immensely depending on depth and exposure: currents differ up to 9-fold within habitats only separated by 3 m depth and 15-fold between exposed, oblique and sheltered habitats. Comparisons to ambient weather conditions reveal that currents around Lizard Island are largely wind driven. Zero to 22.5 knot winds correspond directly to currents of 0 to >82 cms⁻¹, while tidal currents rarely exceed 5.5 cms⁻¹. Rather, current velocity increases exponentially as a function of wave height (0 to 1.6 m and frequency (0.54 to 0.20 Hz, emphasizing the enormous effect of wind and waves on organisms in these shallow coral reef habitats.

  12. Sensor integration in radioactive environments

    Science.gov (United States)

    Harfensteller, Mark; Schilp, Michael; Eursch, Andreas; Zaeh, Michael F.

    2004-12-01

    Radioactive material of high activity levels has to be handled in a nuclear medicine environment. Until now most of these activities are done manually or by rudimentally automated processes. To increase radiation safety and process quality, smart automation strategies for these processes have to be developed. Especially long-term processes with radioactive materials have to be automated in early stages of development. This leads to a certain flexibility regarding requirements demanding an adjustable automation concept. The application of radiation hardened sensors is expensive but even these sensors will be destroyed by radiation effects. To allow therefore standard sensors to be used in radioactive environments, different strategies have been tested: In general, the sensors must be applied in a way to allow an easy access to sensors for replacement purposes. But this approach might not be sophisticated. An additional solution is the reduction of exposure of sensitive parts such as electronics. This means dividing the sensor in a measuring part which is placed in the radioactive environment and in a sensitive, shielded control part as it is realized by fibre optic sensors. The implementation of these approaches is demonstrated in sensor applications for radium handling systems e. g. contactless control of the needle clearance of a dispensing system via a fibre optic sensor. Further scenarios for sensor integration problems are presented in this paper.

  13. Flexible Temperature Sensors on Fibers

    OpenAIRE

    Sibinski, Maciej; Jakubowska, Malgorzata; Sloma, Marcin

    2010-01-01

    The aim of this paper is to present research dedicated to the elaboration of novel, miniaturized flexible temperature sensors for textronic applications. Examined sensors were manufactured on a single yarn, which ensures their high flexibility and good compatibility with textiles. Stable and linear characteristics were obtained by special technological process and applied temperature profiles. As a thermo-sensitive materials the innovative polymer compositions filled with multiwalled carbon n...

  14. Adding Processing Functionality to the Sensor Web

    Science.gov (United States)

    Stasch, Christoph; Pross, Benjamin; Jirka, Simon; Gräler, Benedikt

    2017-04-01

    The Sensor Web allows discovering, accessing and tasking different kinds of environmental sensors in the Web, ranging from simple in-situ sensors to remote sensing systems. However, (geo-)processing functionality needs to be applied to integrate data from different sensor sources and to generate higher level information products. Yet, a common standardized approach for processing sensor data in the Sensor Web is still missing and the integration differs from application to application. Standardizing not only the provision of sensor data, but also the processing facilitates sharing and re-use of processing modules, enables reproducibility of processing results, and provides a common way to integrate external scalable processing facilities or legacy software. In this presentation, we provide an overview on on-going research projects that develop concepts for coupling standardized geoprocessing technologies with Sensor Web technologies. At first, different architectures for coupling sensor data services with geoprocessing services are presented. Afterwards, profiles for linear regression and spatio-temporal interpolation of the OGC Web Processing Services that allow consuming sensor data coming from and uploading predictions to Sensor Observation Services are introduced. The profiles are implemented in processing services for the hydrological domain. Finally, we illustrate how the R software can be coupled with existing OGC Sensor Web and Geoprocessing Services and present an example, how a Web app can be built that allows exploring the results of environmental models in an interactive way using the R Shiny framework. All of the software presented is available as Open Source Software.

  15. Electronic detectors for electron microscopy.

    Science.gov (United States)

    Faruqi, A R; Henderson, R

    2007-10-01

    Due to the increasing popularity of electron cryo-microscopy (cryoEM) in the structural analysis of large biological molecules and macro-molecular complexes and the need for simple, rapid and efficient readout, there is a persuasive need for improved detectors. Commercial detectors, based on phosphor/fibre optics-coupled CCDs, provide adequate performance for many applications, including electron diffraction. However, due to intrinsic light scattering within the phosphor, spatial resolution is limited. Careful measurements suggest that CCDs have superior performance at lower resolution while all agree that film is still superior at higher resolution. Consequently, new detectors are needed based on more direct detection, thus avoiding the intermediate light conversion step required for CCDs. Two types of direct detectors are discussed in this review. First, there are detectors based on hybrid technology employing a separate pixellated sensor and readout electronics connected with bump bonds-hybrid pixel detectors (HPDs). Second, there are detectors, which are monolithic in that sensor and readout are all in one plane (monolithic active pixel sensor, MAPS). Our discussion is centred on the main parameters of interest to cryoEM users, viz. detective quantum efficiency (DQE), resolution or modulation transfer function (MTF), robustness against radiation damage, speed of readout, signal-to-noise ratio (SNR) and the number of independent pixels available for a given detector.

  16. Modulation of electron tunneling in a nanoparticle array by sound waves: an avenue to high-speed, high-sensitivity sensors.

    Science.gov (United States)

    Berry, Vikas; Saraf, Ravi F

    2011-09-05

    Using an electrostatic self-assembly process, metal nanoparticles are deposited on polyelectrolyte fibers such that the interparticle distance between the nanoparticles is comparable to the polyelectrolyte's molecular width. By modulating the dielectric properties of the interparticle polymer layer, a highly sensitive, reversible humidity sensor with an ultrafast response time of ≈3 ms is demonstrated. The higher sensitivity at low humidity shows a conductivity increase by over two orders of magnitude in response to a change in relative humidity from 21 to 1%. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Gas Sensor

    KAUST Repository

    Luebke, Ryan

    2015-01-22

    A gas sensor using a metal organic framework material can be fully integrated with related circuitry on a single substrate. In an on-chip application, the gas sensor can result in an area-efficient fully integrated gas sensor solution. In one aspect, a gas sensor can include a first gas sensing region including a first pair of electrodes, and a first gas sensitive material proximate to the first pair of electrodes, wherein the first gas sensitive material includes a first metal organic framework material.

  18. Flexible Temperature Sensors on Fibers

    Directory of Open Access Journals (Sweden)

    Marcin Sloma

    2010-08-01

    Full Text Available The aim of this paper is to present research dedicated to the elaboration of novel, miniaturized flexible temperature sensors for textronic applications. Examined sensors were manufactured on a single yarn, which ensures their high flexibility and good compatibility with textiles. Stable and linear characteristics were obtained by special technological process and applied temperature profiles. As a thermo-sensitive materials the innovative polymer compositions filled with multiwalled carbon nanotubes were used. Elaborated material was adapted to printing and dip-coating techniques to produce NTC composites. Nanotube sensors were free from tensometric effect typical for other carbon-polymer sensor, and demonstrated TCR of 0.13%/K. Obtained temperature sensors, compatible with textile structure, can be applied in rapidly developing smart textiles and be used for health and protections purposes.

  19. Electronic Nose and Electronic Tongue

    Science.gov (United States)

    Bhattacharyya, Nabarun; Bandhopadhyay, Rajib

    Human beings have five senses, namely, vision, hearing, touch, smell and taste. The sensors for vision, hearing and touch have been developed for several years. The need for sensors capable of mimicking the senses of smell and taste have been felt only recently in food industry, environmental monitoring and several industrial applications. In the ever-widening horizon of frontier research in the field of electronics and advanced computing, emergence of electronic nose (E-Nose) and electronic tongue (E-Tongue) have been drawing attention of scientists and technologists for more than a decade. By intelligent integration of multitudes of technologies like chemometrics, microelectronics and advanced soft computing, human olfaction has been successfully mimicked by such new techniques called machine olfaction (Pearce et al. 2002). But the very essence of such research and development efforts has centered on development of customized electronic nose and electronic tongue solutions specific to individual applications. In fact, research trends as of date clearly points to the fact that a machine olfaction system as versatile, universal and broadband as human nose and human tongue may not be feasible in the decades to come. But application specific solutions may definitely be demonstrated and commercialized by modulation in sensor design and fine-tuning the soft computing solutions. This chapter deals with theory, developments of E-Nose and E-Tongue technology and their applications. Also a succinct account of future trends of R&D efforts in this field with an objective of establishing co-relation between machine olfaction and human perception has been included.

  20. Aptamer Sensors

    OpenAIRE

    Marrazza, Giovanna

    2017-01-01

    In the last years, great progress has been accomplished in the development of aptamer sensors with different transducers. In order to improve the sensitivity of these biosensors, several methodologies have been employed. In this Special Issue, the state of art and the future trends in the field of aptamer sensors have been explored.

  1. Soldier sensor

    Science.gov (United States)

    Kossives, Dean P.

    2010-04-01

    A new sensor system, whose functionality is not reliant on mass spectrometric or ionization methods, is combined with a substrate technology which allows for separately optimized control circuits and standardized advanced sensors in a simple packaging methodology to foster an entirely new generation of modular optical sensors. These sensors will be based on biologic and chromic compounds. The compounds will utilize reversible reaction chemistry to enable self cleaning. The detector's operation is based on simple changes in absorbance, reflectance, color, or other optical properties. The time to saturation of the sensor will determine the relative concentration in the air. A detection scheme based on these properties will function in high background levels and also be able to pick up low level concentrations as well.

  2. Pathogen Sensors

    Directory of Open Access Journals (Sweden)

    Joseph Irudayaraj

    2009-10-01

    Full Text Available The development of sensors for detecting foodborne pathogens has been motivated by the need to produce safe foods and to provide better healthcare. However, in the more recent times, these needs have been expanded to encompass issues relating to biosecurity, detection of plant and soil pathogens, microbial communities, and the environment. The range of technologies that currently flood the sensor market encompass PCR and microarray-based methods, an assortment of optical sensors (including bioluminescence and fluorescence, in addition to biosensor-based approaches that include piezoelectric, potentiometric, amperometric, and conductometric sensors to name a few. More recently, nanosensors have come into limelight, as a more sensitive and portable alternative, with some commercial success. However, key issues affecting the sensor community is the lack of standardization of the testing protocols and portability, among other desirable elements, which include timeliness, cost-effectiveness, user-friendliness, sensitivity and specificity. [...

  3. Piezoelectric Sensor Evaluation for Structural Health Monitoring of Cryogenic Structures

    Science.gov (United States)

    Lassiter, John; Engberg, Robert

    2005-01-01

    This viewgraph presentation provides an overview of Structural Health Monitoring (SHM), and profiles piezoelectric sensors useful for SHM of cryogenic structures. The presentation also profiles impedance tests and other SHM tests conducted at Marshall Space Flight Center (MSFC).

  4. Miniaturised optical displacement sensor

    Science.gov (United States)

    Gindele, Frank; Gaul, Frank; Kraus, Silvio; Sigloch, Susanne; Teubner, Ulrich

    2004-09-01

    The primary object presented in this contribution is the miniaturization of a displacement sensor system with the potential for high accuracy measurements and for cost-effective production in polymers. The measurement of linear displacements can be performed by different methods e.g. magnetoresistive, potentiometric, electromagnetic or inductive encoder systems. For movements in the millimeter range and above the most precise systems are based on optical methods. The displacement measurement of our sensor system uses the intensity modulation of two amplitude gratings, moving relative to each other and illuminated by a LED. To increase the system resolution and the signal quality the grating/detector combination is divided into four areas which are phase shifted to each other. The grating period is 25 μm with a geometrical accuracy below 1 μm. The amplitude gratings have been processed on a glass substrate lithographically. Applying electro-discharge machining a miniaturised optical bench for the passive alignment of the optical and the opto-electronic components has been realised. The sensor has an overall size of 6x4x3 mm3 and is designed for the future replication in one single polymer part. In combination with an electronic interpolation the sensor will be capable for a sub-micrometer accuracy.

  5. Sensors Applications, Volume 2, Sensors in Intelligent Buildings

    Science.gov (United States)

    Gassmann, Oliver; Meixner, Hans

    2001-06-01

    Taken as a whole, this series covers all major fields of application for commercial sensors, as well as their manufacturing techniques and major types. As such the series does not treat bulk sensors, but rather places strong emphasis on microsensors, microsystems and integrated electronic sensor packages. Each of the individual volumes is tailored to the needs and queries of readers from the relevant branch of industry. A comprehensive survey for engineers and scientists on the different sensor types for energy efficiency, security, maintenance management and smart house devices. As such, the text covers air conditioning, large premises control, service and installation monitoring as well as emergency control. It also discusses the strengths and weaknesses in each case, illustrating which sensor is used in which subsystem and why.

  6. Sensors in Smartphones

    OpenAIRE

    Hu, Mengchen

    2010-01-01

    With the booming development of scientific technology, the mobile phone is no longer a simple communication tool, but a portable electronic device with integrated functions. You can use the phone to listen to music, watch movies, take pictures and so on. Mobile phones have gradually entered into human’s daily life. In this case, the various sensors are emerged in smartphones. The requirements on smartphones are increasingly high. Telephone, SMS, multimedia, etc., are just basic applications,...

  7. Roll-to-roll paper sensors (ROPAS); Wireless communicating sensors on paper in the logistic chain

    NARCIS (Netherlands)

    Rentrop, C.; Rubingh, J.E.J.M.; Lelieveld, R.; Sandberg, H.

    2014-01-01

    The ROPAS project (Roll-to-roll paper sensors) combines high end electronics and wireless sensors with low cost paper substrates and processing techniques that can be applied on a large scale. Paper is the next step in the printed electronics roadmap of utilising cheaper substrate materials as a

  8. The ATLAS Silicon Pixel Sensors

    CERN Document Server

    Alam, M S; Einsweiler, K F; Emes, J; Gilchriese, M G D; Joshi, A; Kleinfelder, S A; Marchesini, R; McCormack, F; Milgrome, O; Palaio, N; Pengg, F; Richardson, J; Zizka, G; Ackers, M; Andreazza, A; Comes, G; Fischer, P; Keil, M; Klasen, V; Kühl, T; Meuser, S; Ockenfels, W; Raith, B; Treis, J; Wermes, N; Gössling, C; Hügging, F G; Wüstenfeld, J; Wunstorf, R; Barberis, D; Beccherle, R; Darbo, G; Gagliardi, G; Gemme, C; Morettini, P; Musico, P; Osculati, B; Parodi, F; Rossi, L; Blanquart, L; Breugnon, P; Calvet, D; Clemens, J-C; Delpierre, P A; Hallewell, G D; Laugier, D; Mouthuy, T; Rozanov, A; Valin, I; Aleppo, M; Caccia, M; Ragusa, F; Troncon, C; Lutz, Gerhard; Richter, R H; Rohe, T; Brandl, A; Gorfine, G; Hoeferkamp, M; Seidel, SC; Boyd, GR; Skubic, P L; Sícho, P; Tomasek, L; Vrba, V; Holder, M; Ziolkowski, M; D'Auria, S; del Papa, C; Charles, E; Fasching, D; Becks, K H; Lenzen, G; Linder, C

    2001-01-01

    Prototype sensors for the ATLAS silicon pixel detector have been developed. The design of the sensors is guided by the need to operate them in the severe LHC radiation environment at up to several hundred volts while maintaining a good signal-to-noise ratio, small cell size, and minimal multiple scattering. The ability to be operated under full bias for electrical characterization prior to the attachment of the readout integrated circuit electronics is also desired.

  9. Ultra-Low-Power MEMS Selective Gas Sensors

    Science.gov (United States)

    Stetter, Joseph

    2012-01-01

    This innovation is a system for gas sensing that includes an ultra-low-power MEMS (microelectromechanical system) gas sensor, combined with unique electronic circuitry and a proprietary algorithm for operating the sensor. The electronics were created from scratch, and represent a novel design capable of low-power operation of the proprietary MEMS gas sensor platform. The algorithm is used to identify a specific target gas in a gas mixture, making the sensor selective to that target gas.

  10. Piezoceramic Sensors

    CERN Document Server

    Sharapov, Valeriy

    2011-01-01

    This book presents the latest and complete information about various types of piezosensors. A sensor is a converter of the measured physical size to an electric signal. Piezoelectric transducers and sensors are based on piezoelectric effects. They have proven to be versatile tools for the measurement of various processes. They are used for quality assurance, process control and for research and development in many different industries. In each area of application specific requirements to the parameters of transducers and sensors are developed. This book presents the fundamentals, technical des

  11. Systems approach to the design of the CCD sensors and camera electronics for the AIA and HMI instruments on solar dynamics observatory

    Science.gov (United States)

    Waltham, N.; Beardsley, S.; Clapp, M.; Lang, J.; Jerram, P.; Pool, P.; Auker, G.; Morris, D.; Duncan, D.

    2017-11-01

    Solar Dynamics Observatory (SDO) is imaging the Sun in many wavelengths near simultaneously and with a resolution ten times higher than the average high-definition television. In this paper we describe our innovative systems approach to the design of the CCD cameras for two of SDO's remote sensing instruments, the Atmospheric Imaging Assembly (AIA) and the Helioseismic and Magnetic Imager (HMI). Both instruments share use of a custom-designed 16 million pixel science-grade CCD and common camera readout electronics. A prime requirement was for the CCD to operate with significantly lower drive voltages than before, motivated by our wish to simplify the design of the camera readout electronics. Here, the challenge lies in the design of circuitry to drive the CCD's highly capacitive electrodes and to digitize its analogue video output signal with low noise and to high precision. The challenge is greatly exacerbated when forced to work with only fully space-qualified, radiation-tolerant components. We describe our systems approach to the design of the AIA and HMI CCD and camera electronics, and the engineering solutions that enabled us to comply with both mission and instrument science requirements.

  12. Organic semiconductors in sensor applications

    CERN Document Server

    Malliaras, George; Owens, Róisín

    2008-01-01

    Organic semiconductors offer unique characteristics such as tunability of electronic properties via chemical synthesis, compatibility with mechanically flexible substrates, low-cost manufacturing, and facile integration with chemical and biological functionalities. These characteristics have prompted the application of organic semiconductors and their devices in physical, chemical, and biological sensors. This book covers this rapidly emerging field by discussing both optical and electrical sensor concepts. Novel transducers based on organic light-emitting diodes and organic thin-film transistors, as well as systems-on-a-chip architectures are presented. Functionalization techniques to enhance specificity are outlined, and models for the sensor response are described.

  13. Dopant profiling of focused ion beam milled semiconductors using off-axis electron holography; reducing artifacts, extending detection limits and reducing the effects of gallium implantation

    DEFF Research Database (Denmark)

    Cooper, David; Ailliot, Cyril; Barnes, Jean-Paul

    2010-01-01

    Focused ion beam (FIB) milling is one of the few specimen preparation techniques that can be used to prepare parallel-sided specimens with nm-scale site specificity for examination using off-axis electron holography in the transmission electron microscope (TEM). However, FIB milling results in th...

  14. Vibrissa Sensor

    Science.gov (United States)

    2016-09-30

    Docket No. 300119 1 of 11 VIBRISSA SENSOR STATEMENT OF GOVERNMENT INTEREST [0001] The invention described herein may be manufactured and used by...REFERENCE TO OTHER PATENT APPLICATIONS [0002] None. BACKGROUND OF THE INVENTION (1) Field of the Invention [0003] The present invention provides a...vibrissa in two dimensions. SUMMARY OF THE INVENTION [0010] Accordingly, it is an object of the present invention to provide a sensor capable of

  15. A brief overview of state-of-the-art electronics in physical oceanographic instrumentation

    Digital Repository Service at National Institute of Oceanography (India)

    Charyulu, R.J.K.

    of the autonomous under water remotely operated instruments, in which robotic technology is used. In these AUVs the integration of CTDs, Flourescence sensors, GPS, Sonars etc. led to unmanned tele-controlled & telecommanded submersibles and ocean profiling... system, initially with electro-mechanical graphic recorders, & now with computerized data-acquisition types using electronic MK-21 deck units ( in Sippican, U.S.A. makes) and that too deeper (1800metres) versions now available. The conductivity...

  16. Live-cell imaging of biothiols via thiol/disulfide exchange to trigger the photoinduced electron transfer of gold-nanodot sensor

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Ching-Ping; Wu, Te-Haw; Liu, Chia-Yeh; Lin, Shu-Yi, E-mail: shuyi@nhri.org.tw

    2014-11-07

    Highlights: • The ultrasmall size, PAMAM dendrimer-entrapped Au{sub 8}-clusters were synthesized. • Thiol/disulfide exchange with biothiols to release 2-PyT resulted in quenching. • The sensing platform can detect both low and high molecular weight thiols. • Capable of imaging biothiols including protein thiols in living cells. - Abstract: Biothiols have been reported to involve in intracellular redox-homeostasis against oxidative stress. In this study, a highly selective and sensitive fluorescent probe for sensing biothiols is explored by using an ultrasmall gold nanodot (AuND), the dendrimer-entrapped Au{sub 8}-cluster. This strategy relies upon a thiol/disulfide exchange to trigger the fluorescence change through a photoinduced electron transfer (PET) process between the Au{sub 8}-cluster (as an electron donor) and 2-pyridinethiol (2-PyT) (as an electron acceptor) for sensing biothiols. When 2-PyT is released via the cleavage of disulfide bonds by biothiols, the PET process from the Au{sub 8}-cluster to 2-PyT is initiated, resulting in fluorescence quenching. The fluorescence intensity was found to decrease linearly with glutathione (GSH) concentration (0–1500 μM) at physiological relevant levels and the limit of detection for GSH was 15.4 μM. Compared to most nanoparticle-based fluorescent probes that are limited to detect low molecular weight thiols (LMWTs; i.e., GSH and cysteine), the ultrasmall Au{sub 8}-cluster-based probe exhibited less steric hindrance and can be directly applied in selectively and sensitively detecting both LMWTs and high molecular weight thiols (HMWTs; i.e., protein thiols). Based on such sensing platform, the surface-functionalized Au{sub 8}-cluster has significant promise for use as an efficient nanoprobe for intracellular fluorescence imaging of biothiols including protein thiols in living cells whereas other nanoparticle-based fluorescent probes cannot.

  17. REVIEW ARTICLE: A taste sensor

    Science.gov (United States)

    Toko, Kiyoshi

    1998-12-01

    A multichannel taste sensor, namely an electronic tongue, with global selectivity is composed of several kinds of lipid/polymer membranes for transforming information about substances producing taste into electrical signals, which are input to a computer. The sensor output exhibits different patterns for chemical substances which have different taste qualities such as saltiness, sourness and bitterness, whereas it exhibits similar patterns for chemical substances with similar tastes. The sensor responds to the taste itself, as can be understood from the fact that taste interactions such as the suppression effect, which appears for mixtures of sweet and bitter substances, can be reproduced well. The suppression of the bitterness of quinine and a drug substance by sucrose can be quantified. Amino acids can be classified into several groups according to their own tastes on the basis of sensor outputs. The tastes of foodstuffs such as beer, coffee, mineral water, milk, sake, rice, soybean paste and vegetables can be discussed quantitatively using the taste sensor, which provides the objective scale for the human sensory expression. The flavour of a wine is also discriminated using the taste-odour sensory fusion conducted by combining the taste sensor and an odour-sensor array using conducting polymer elements. The taste sensor can also be applied to measurements of water pollution. Miniaturization of the taste sensor using FET produces the same characteristics as those of the above taste sensor by measuring the gate-source voltage. Use of the taste sensor will lead to a new era of food and environmental sciences.

  18. User's Guide: An Enhanced Modified Faraday Cup for the Profiling of the Power Density Distribution in Electron Beams

    Energy Technology Data Exchange (ETDEWEB)

    Elmer, J W; Teruya, A T; Palmer, T A

    2002-06-01

    This handbook describes the assembly and operation of an enhanced Modified Faraday Cup (MFC) diagnostic device for measuring the power density distribution of high power electron beams used for welding. The most recent version of this diagnostic device, [1] Version 2.0, contains modifications to the hardware components of previous MFC designs.[2] These modifications allow for more complete capture of the electrons and better electrical grounding, thus improving the quality of the acquired data and enabling a more accurate computed tomographic (CT) reconstruction [3,4] of the power density distribution of the electron beam to be performed. [ 5-9

  19. Graphene Based Flexible Gas Sensors

    Science.gov (United States)

    Yi, Congwen

    Graphene is a novel carbon material with great promise for a range of applications due to its electronic and mechanical properties. Its two-dimensional nature translates to a high sensitivity to surface chemical interactions thereby making it an ideal platform for sensors. Graphene's electronic properties are not degraded due to mechanical flexing or strain (Kim, K. S., et al. nature 07719, 2009) offering another advantage for flexible sensors integrated into numerous systems including fabrics, etc. We have demonstrated a graphene NO2 sensor on a solid substrate (100nm SiO2/heavily doped silicon). Three different methods were used to synthesize graphene and the sensor fabrication process was optimized accordingly. Water is used as a controllable p-type dopant in graphene to study the relationship between doping and graphene's response to NO2 . Experimental results show that interface water between graphene and the supporting SiO2 substrate induces higher p-doping in graphene, leading to a higher sensitivity to NO2, consistent with theoretical predications (Zhang, Y. et al., Nanotechnology 20(2009) 185504). We have also demonstrated a flexible and stretchable graphene-based sensor. Few layer graphene, grown on a Ni substrate, is etched and transferred to a highly stretchable polymer substrate (VHB from 3M) with preloaded stress, followed by metal contact formation to construct a flexible, stretchable sensor. With up to 500% deformation caused by compressive stress, graphene still shows stable electrical response to NO2. Our results suggest that higher compressive stress results in smaller sheet resistance and higher sensitivity to NO2. A possible molecular detection sensor utilizing Surface Enhanced Raman Spectrum (SERS) based on a graphene/gallium nanoparticles platform is also studied. By correlating the enhancement of the graphene Raman modes with metal coverage, we propose that the Ga transfers electrons to the graphene creating local regions of enhanced

  20. DMSP SSM/T-2 microwave water vapor profiler

    Science.gov (United States)

    Galin, Israel; Brest, Dennis H.; Martner, Glen R.

    1993-08-01

    The Special Sensor Microwave water vapor profiler (SSM/T-2) is a five channel passive microwave sensor that operates in the 90 - 190 GHz frequency band. The instrument was developed by Aerojet Electronic Systems Division (AESD) of GenCorp Aerojet under a contract to the Defense Meteorological Satellite Program (DMSP). The first in a series of these instruments was successfully orbited in November 1991. This paper addresses details of the instrument configuration, as well as relevant information on the status of the project. A block diagram of the instrument is described in relation to its electrical, environmental and reliability requirements. Performance data measured in laboratory conditions is presented along with data from the operating unit in orbit.

  1. Introduction to printed electronics

    CERN Document Server

    Suganuma, Katsuaki

    2014-01-01

    This book describes in detail modern technologies for printed electronics, explaining how nanotechnology and modern printing technology are merging to revolutionize electronics fabrication of thin, lightweight, large, and inexpensive products. Readers will benefit from the explanations of materials, devices and circuits used to design and implement the latest applications of printed electronics, such as thin flexible OLED displays, organic solar cells, OLED lighting, smart wallpaper, sensors, logic, memory and more.

  2. Design and characterisation of high electron mobility transistors for use in a monolithic GaAs X-ray imaging sensor

    Energy Technology Data Exchange (ETDEWEB)

    Boardman, D.A. E-mail: d.boardman@surrey.ac.uk; Sellin, P.J

    2001-06-21

    A new design of monolithic GaAs pixel detector is proposed for medical and synchrotron applications. In this device a semi-insulating GaAs wafer will be used as both the detector element and the substrate for the integrated charge readout matrix. The charge readout matrix consists of High Electron Mobility Transistors (HEMTs), which are grown epitaxially onto the GaAs substrate. Experimental characterisation of HEMTs has been carried out and their suitability for the proposed imaging device is assessed. Temperature measurements on initial devices showed the threshold voltage to be stable from room temperature down to -15 degree sign C. HEMT designs with lower leakage current that operate in enhancement mode have been fabricated and modelled using the Silvaco simulation package. These optimised devices have been fabricated using a gate recess, and exhibit enhancement mode operation and significantly reduced gate leakage currents.

  3. Electronic noses and their applications in environmental monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Hashem, S.; Keller, P.E.; Kouzes, R.T.; Kangas, L.J. [Pacific Northwest Lab., Richland, WA (United States)

    1995-12-31

    Compact, portable systems capable of quickly identifying contaminants in the field are of great importance when monitoring the environment. In this paper, we examine the effectiveness of using artificial neural networks for real-time data analysis of a sensor array. Analyzing the sensor data in parallel may allow for rapid identification of contaminants in the field without requiring highly selective component sensors. A sensor array combined with a data analysis module is referred to as an electronic nose. In this paper, we investigate the trade off between sensor sensitivity and selectivity relating to the applications of neural network based-electronic noses in environmental monitoring. We use a prototype electronic nose which consists of nine tin-oxide Taguchi-type sensors, a temperature sensor, and a humidity sensor. We illustrate that by using neural network based analysis of a sensor data, the selectivity of a sensor array may be significantly improved, especially when some (or all) sensors are not highly selective.

  4. Nanostructures for Electronic and Sensing Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed project will develop sensors and electronic components from metal oxide based nanotubes and nanowires. These nanostructured materials will be grown...

  5. Electrospun Based Polyaniline Sensors - A Review

    Science.gov (United States)

    Rozemarie, M. L.; Andrei, B.; Liliana, H.; Cramariuc, R.; Cramariuc, O.

    2017-06-01

    Polyaniline is a polymer with outstanding electronic conductivity and good response to molecules at room temperature. This review focuses on the many uses of electrospun polyaniline nanofibers as chemical sensor with high sensitivity and functionality, providing a concise report of the present status of polyaniline gas sensing applications. Latest developments in this area are reported and the capability of PANI sensors to detect various gases is emphasized. Difficulties that may obstruct practical uses of these sensors are also summarized.

  6. Single electron-ics with carbon nanotubes

    OpenAIRE

    Götz, G.T.J.

    2010-01-01

    We experimentally investigate Quantum Dots, formed in Carbon Nanotubes. The first part of this thesis deals with charge sensing on such quantum dots. The charge sensor is a metallic Single-electron-transistor, sensitive to the charge of a single electron on the quantum dot. We use this technique for real-time charge readout and precise tuning of the tunnel barriers of the quantum dot. The second part of this thesis describes the realization of exceptionally clean Carbon Nanotube quantum dots....

  7. Nanomaterial-Enabled Wearable Sensors for Healthcare.

    Science.gov (United States)

    Yao, Shanshan; Swetha, Puchakayala; Zhu, Yong

    2018-01-01

    Highly sensitive wearable sensors that can be conformably attached to human skin or integrated with textiles to monitor the physiological parameters of human body or the surrounding environment have garnered tremendous interest. Owing to the large surface area and outstanding material properties, nanomaterials are promising building blocks for wearable sensors. Recent advances in the nanomaterial-enabled wearable sensors including temperature, electrophysiological, strain, tactile, electrochemical, and environmental sensors are presented in this review. Integration of multiple sensors for multimodal sensing and integration with other components into wearable systems are summarized. Representative applications of nanomaterial-enabled wearable sensors for healthcare, including continuous health monitoring, daily and sports activity tracking, and multifunctional electronic skin are highlighted. Finally, challenges, opportunities, and future perspectives in the field of nanomaterial-enabled wearable sensors are discussed. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Novel nanostructured oxygen sensor

    Science.gov (United States)

    Boardman, Alan James

    New government regulations and industry requirements for medical oxygen sensors require the development of alternate materials and process optimization of primary sensor components. Current oxygen sensors are not compliant with the Restriction of Hazardous Substances (RoHS) Directive. This work focused on two areas. First, was finding suitable readily available materials for the sensor anodes. Second was optimizing the processing of the sensor cathode membrane for reduced delamination. Oxygen sensors were made using tin (Sn) and bismuth (Bi) electrodes, potassium hydroxide (KOH) and acetic acid (CH3COOH) electrolytes with platinum (Pt) and gold (Au) reference electrodes. Bi electrodes were fabricated by casting and pressing processes. Electrochemical characterization of the Sn and Bi electrodes was performed by Cyclic Voltammetry (CV), Electrochemical Impedance Spectroscopy (EIS) and sensing characterization per BSEN ISO 21647:2009 at various oxygen percentages, 0%, 20.9% and 100% oxygen levels with an automated test apparatus. The Sn anode with both electrolyte solutions showed good oxygen sensing properties and performance in a sensor. This system shows promise for replacement of Pb electrodes as required by the RoHS Directive. The Bi anode with Au cathode in both KOH and CH3COOH electrolytes showed acceptable performance and oxygen sensing properties. The Bi anodes fabricated by separate manufacturing methods demonstrated effectiveness for use in medical oxygen sensors. Gold thin films were prepared by magnetron sputtering on Flouroethylene Polymer (FEP) films. The FEP substrate temperature ranged from -77°C to 50°C. X-Ray Diffraction (XRD) and 4-point resistivity characterized the effects of substrate temperature to Au thin film particle size. XRD peak broadening and resistivity measurements showed a strong correlation of particle size to FEP substrate temperature. Particle size at 50°C was 594A and the -77°C particle size was 2.4 x 103A. Substrate

  9. Sensors for the Senses

    DEFF Research Database (Denmark)

    Brooks, Anthony Lewis

    2015-01-01

    -worn sensors (volumetric, linear and planar interface profiles). Mapping of sourced human data is to a variety of digital content including art-based (music making, digital painting, lighting effects), video games, Virtual Reality and robotic devices. System adaptability promotes participant profile matching e...... product and industry start-ups. At the core of the research is a rethinking in the way a human interacts with ICT. Current research explores a concept of dynamic air and alternative physical-virtual environments. Conclusions introduce a suggested need of increased researcher awareness of post......In his ACM Computers in Entertainment article, titled "Artist and Audience: Emerging the Nano-entertainment experience", the author posited on how Inhabited Information Spaces, created as core catalyst of research, may be questioned as a multisensory future virtual work of art. This themed Human...

  10. Electronic thermal sensor and Data Collection Platform technology: Part 5 in Thermal surveillance of active volcanoes using the Landsat-1 Data Collection System

    Science.gov (United States)

    Preble, Duane M.; Friedman, Jules D.; Frank, David

    1976-01-01

    Five Data Collection Platforms (DCP) were integrated electronically with thermall sensing systems, emplaced and operated in an analog mode at selected thermally significant volcanic and geothermal sites. The DCP's transmitted 3260 messages comprising 26,080 ambient, surface, and near-surface temperature records at an accuracy of ±1.15 °C for 1121 instrument days between November 14, 1972 and April 17, 1974. In harsh, windy, high-altitude volcanic environments the DCP functioned best with a small dipole antenna. Sixteen kg of alkaline batteries provided a viable power supply for the DCP systems, operated at a low-duty cycle, for 5 to 8 months. A proposed solar power supply system would lengthen the period of unattended operation of the system considerably. Special methods of data handling such as data storage via a proposed memory system would increase the significance of the twice-daily data reception enabling the DCP's to record full diurnal-temperature cycles at volcanic or geothermal sites. Refinements in the temperature-monitoring system designed and operated in experiment SR 251 included a backup system consisting of a multipoint temperature scanner, a servo mechanism and an analog-to-digital recorder. Improvements were made in temperature-probe design and in construction of corrosion-resistant seals by use of a hydrofluoric-acid-etching technique.

  11. Extending lifetime of wireless sensor networks using multi-sensor ...

    Indian Academy of Sciences (India)

    In this proposed methodology, the collected temperature tand humidity data are processed by multi-sensor data fusion techniques, which help in decreasing the energy ... Department of Computer Science and Engineering, Sathyabama University, Chennai 600119, India; Department of Electronics and Control Engineering, ...

  12. Dose profile for electron beams obtained with CaSO{sub 4}:Ce,Eu thermoluminescent dosimeters; Perfil de dose de feixes de eletrons obtidos com dosimetros termoluminescentes de CaSO{sub 4}:Ce,Eu

    Energy Technology Data Exchange (ETDEWEB)

    Nunes, Maira G.; Rodrigues, Leticia L.C., E-mail: mgnunes@ipen.br [Instituto de Pesquisas Energerticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2012-12-15

    The calcium sulphate activated with cerium and europium (CaSO{sub 4}:Ce,Eu) thermoluminescent dosimeters (TLD) recently developed at Nuclear and Energy Research Institute as well as the calcium sulphate activated with dysprosium (CaSO{sub 4}: Dy) and lithium fluoride activated with magnesium and titanium, (LiF:Mg,Ti; TLD-100) TLDs, with long term applications in dosimetry and considered as standards, were used to obtain the dose profile for 3.43, 5.48, 8.27 and 11.67 MeV electron beams generated by a linear accelerator Clinac 2100-C (Varian) in the reference conditions defined by the TRS-398 code of practice. The routine dosimetry of the electron beams, performed with a calibrated ionization chamber, ensures that the electron beams fulfill the requirements of flatness and symmetry established in this code of practice. Thus, as the TRS-398 Code of Practice requirements are fulfilled by the measurements performed with the new TLD type, CaSO{sub 4}:Ce,Eu may be applied in clinical dosimetry of high energy electron beams. (author)

  13. Multiparametric methane sensor for environmental monitoring

    Science.gov (United States)

    Borecki, M.; Duk, M.; Kociubiński, A.; Korwin-Pawlowski, M. L.

    2016-12-01

    Today, methane sensors find applications mostly in safety alarm installations, gas parameters detection and air pollution classification. Such sensors and sensors elements exists for industry and home use. Under development area of methane sensors application is dedicated to ground gases monitoring. Proper monitoring of soil gases requires reliable and maintenance-free semi-constant and longtime examination at relatively low cost of equipment. The sensors for soil monitoring have to work on soil probe. Therefore, sensor is exposed to environment conditions, as a wide range of temperatures and a full scale of humidity changes, as well as rain, snow and wind, that are not specified for classical methane sensors. Development of such sensor is presented in this paper. The presented sensor construction consists of five commercial non dispersive infra-red (NDIR) methane sensing units, a set of temperature and humidity sensing units, a gas chamber equipped with a micro-fan, automated gas valves and also a microcontroller that controls the measuring procedure. The electronics part of sensor was installed into customized 3D printed housing equipped with self-developed gas valves. The main development of proposed sensor is on the side of experimental evaluation of construction reliability and results of data processing included safety procedures and function for hardware error correction. Redundant methane sensor units are used providing measurement error correction as well as improved measurement accuracy. The humidity and temperature sensors are used for internal compensation of methane measurements as well as for cutting-off the sensor from the environment when the conditions exceed allowable parameters. Results obtained during environment sensing prove that the gas concentration readings are not sensitive to gas chamber vertical or horizontal position. It is important as vertical sensor installation on soil probe is simpler that horizontal one. Data acquired during six

  14. Material approaches to stretchable strain sensors.

    Science.gov (United States)

    Park, Jaeyoon; You, Insang; Shin, Sangbaie; Jeong, Unyong

    2015-04-27

    With the recent progress made in wearable electronics, devices now require high flexibility and stretchability up to large strain levels (typically larger than 30 % strain). Wearable strain sensors or deformable strain sensors have been gaining increasing research interest because of the rapid development of electronic skins and robotics and because of their biomedical applications. Conventional brittle strain sensors made of metals and piezoresistors are not applicable for such stretchable sensors. This Review summarizes recent advances in stretchable sensors and focuses on material aspects for high stretchability and sensitivity. It begins with a brief introduction to the Wheatstone bridge circuit of conventional resistive strain sensors. Then, studies on the manipulation of materials are reviewed, including waved structural approaches for making metals and semiconductors stretchable, the use of liquid metals, and conductive filler/elastomer composites by using percolation among the fillers. For capacitive strain sensors, the constant conductivity of the electrode is a key factor in obtaining reliable sensors. Possible approaches to developing capacitive strain sensors are presented. This Review concludes with a discussion on the major challenges and perspectives related to stretchable strain sensors. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Profiling the interfacial electron gas of LaAlO{sub 3}/SrTiO{sub 3}(111) heterointerfaces

    Energy Technology Data Exchange (ETDEWEB)

    Gabel, Judith; Zapf, Michael; Scheiderer, Philipp; Schuetz, Philipp; Kirilmaz, Ozan; Sing, Michael; Claessen, Ralph [Physikalisches Institut and Roentgen Center for Complex Material Systems (RCCM), Universitaet Wuerzburg (Germany); Schlueter, Christoph; Lee, Tien-Lin [Diamond Light Source Ltd., Didcot (United Kingdom); Cancellieri, Claudia [EMPA, Laboratory of Joining Technologies and Corrosion, Duebendorf (Switzerland); Rogalev, Victor [Physikalisches Institut and Roentgen Center for Complex Material Systems (RCCM), Universitaet Wuerzburg (Germany); Swiss Light Source, Paul Scherrer Institute, Villigen (Switzerland); Strocov, Vladimir [Swiss Light Source, Paul Scherrer Institute, Villigen (Switzerland)

    2016-07-01

    Akin to the the well established LaAlO{sub 3}(LAO)/SrTiO{sub 3}(STO) (001) a two-dimensional electron system (2DES) also forms at the interface between LAO and STO in (111) orientation. In contrast to the (001) samples, the (111) oriented structures are predicted to display highly non-trivial topological properties induced by symmetry breaking and the peculiar real space lattice topology. We have investigated the electronic structure of the LAO/STO (111) heterostructure by hard and resonant soft X-ray photoemission. The momentum-resolved electronic structure of the interface Ti 3d states showcases the distinctive symmetry of the (111) orientation. These measurements as well as angular resolved hard X-ray photoemission measurements of the Ti 2p core level furthermore allow conclusions to be drawn about the spatial extent of the interfacial 2DES.

  16. Selective control of the radical-scavenging activity of poly(phenols) in aqueous media in terms of their electron-donor properties, using a stable organic radical as chemical sensor.

    Science.gov (United States)

    Mesa, Juan Antonio; Torres, Josep Lluís; Juliá, Luis

    2012-11-15

    The tri-potassium salt of tris(2,3,5,6-tetrachloro-4-hydroxysulphonylphenyl)methyl radical, 3K(+) TSPTM(3-), is a good chemical sensor of the radical-scavenging activity of poly(phenols) in aqueous media. Its water solubility and its stability at all pH values facilitates the study of the influence of the pH of the medium on the activity of poly(phenols). The radical-scavenging activity of three flavonoids of the catechol and pyrogallol type and the activity of catechol, pyrogallol and methyl gallate at pH values 7 and 8 which are close to physiological pH value (7.4) have been measured. This radical species reacts exclusively by an electron transfer mechanism against the reducing poly(phenols). Therefore, the experiments to determine the radical-scavenging activity of poly(phenols) with 3K(+) TSPTM(3-) are related to their ionization potentials (IP). As IP is a function of the pH of the medium, the electron donor ability of a poly(phenol) depends on the acidity or basicity of the fluid in question. The radical-scavenging activity of poly(phenols) 1-6 is higher at pH 8 than at pH 7. 3K(+) TSPTM(3-) is able to discriminate between catecholic and pyrogallolic moieties of poly(phenols) in water solutions by taking measurements at different pH values. By adjusting the pH of the medium 3K(+) TSPTM(3-) will easily detect those moieties (e.g. pyrogallol) most prone to elicit prooxidant effects. Copyright © 2012 Elsevier B.V. All rights reserved.

  17. Vertically stacked nanocellulose tactile sensor.

    Science.gov (United States)

    Jung, Minhyun; Kim, Kyungkwan; Kim, Bumjin; Lee, Kwang-Jae; Kang, Jae-Wook; Jeon, Sanghun

    2017-11-16

    Paper-based electronic devices are attracting considerable attention, because the paper platform has unique attributes such as flexibility and eco-friendliness. Here we report on what is claimed to be the firstly fully integrated vertically-stacked nanocellulose-based tactile sensor, which is capable of simultaneously sensing temperature and pressure. The pressure and temperature sensors are operated using different principles and are stacked vertically, thereby minimizing the interference effect. For the pressure sensor, which utilizes the piezoresistance principle under pressure, the conducting electrode was inkjet printed on the TEMPO-oxidized-nanocellulose patterned with micro-sized pyramids, and the counter electrode was placed on the nanocellulose film. The pressure sensor has a high sensitivity over a wide range (500 Pa-3 kPa) and a high durability of 10(4) loading/unloading cycles. The temperature sensor combines various materials such as poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS), silver nanoparticles (AgNPs) and carbon nanotubes (CNTs) to form a thermocouple on the upper nanocellulose layer. The thermoelectric-based temperature sensors generate a thermoelectric voltage output of 1.7 mV for a temperature difference of 125 K. Our 5 × 5 tactile sensor arrays show a fast response, negligible interference, and durable sensing performance.

  18. Practical electronics for inventors

    CERN Document Server

    Scherz, Paul

    2013-01-01

    Spark your creativity and gain the electronics skills required to transform your innovative ideas into functioning gadgets. This hands-on, updated guide outlines electrical principles and provides thorough, easy-to-follow instructions, schematics, and illustrations. Findout how to select components, safely assemble circuits, perform error tests, and build plug-and-play prototypes. Practical Electronics for Inventors, Third Edition, features all-new chapters on sensors, microcontrollers, modular electronics, and the latest software tools. Coverage includes: Resistors, capacitors, inductors, and transformers Diodes, transistors, and integrated circuits Optoelectronics, solar cells, and phototransistors Sensors, GPS modules, and touch screens Op amps, regulators, and power supplies Digital electronics, LCD displays, and logic gates Microcontrollers and prototyping platforms, including Arduino DC motors, RC servos, and stepper motors Microphones, audio amps, and speakers Modular electronics and prototyping.

  19. Embedded Temperature-Change Sensors

    Science.gov (United States)

    Thakoor, Sarita; Thakoor, Anil; Karmon, Dan

    1995-01-01

    Transducers sensitive to rates of change of temperature embedded in integrated circuits and discrete electronic components damaged by overheating, according to proposal. Used to detect onset of rapid heating and to trigger shutoffs of power or other corrective actions before temperatures rise beyond safe limits. Sensors respond fast and reliably to incipient overheating because they are in direct thermal contact with vulnerable circuit elements.

  20. Dual Cryogenic Capacitive Density Sensor

    Science.gov (United States)

    Youngquist, Robert; Mata, Carlos; Vokrot, Peter; Cox, Robert

    2009-01-01

    A dual cryogenic capacitive density sensor has been developed. The device contains capacitive sensors that monitor two-phase cryogenic flow density to within 1% accuracy, which, if temperature were known, could be used to determine the ratio of liquid to gas in the line. Two of these density sensors, located a known distance apart, comprise the sensor, providing some information on the velocity of the flow. This sensor was constructed as a proposed mass flowmeter with high data acquisition rates. Without moving parts, this device is capable of detecting the density change within a two-phase cryogenic flow more than 100 times a second. Detection is enabled by a series of two sets of five parallel plates with stainless steel, cryogenically rated tubing. The parallel plates form the two capacitive sensors, which are measured by electrically isolated digital electronics. These capacitors monitor the dielectric of the flow essentially the density of the flow and can be used to determine (along with temperature) the ratio of cryogenic liquid to gas. Combining this information with the velocity of the flow can, with care, be used to approximate the total two-phase mass flow. The sensor can be operated at moderately high pressures and can be lowered into a cryogenic bath. The electronics have been substantially improved over the older sensors, incorporating a better microprocessor, elaborate ground loop protection and noise limiting circuitry, and reduced temperature sensitivity. At the time of this writing, this design has been bench tested at room temperature, but actual cryogenic tests are pending

  1. Detection of mechanical instability in DI-fluxgate sensors

    DEFF Research Database (Denmark)

    Pedersen, Lars W.; Matzka, Jürgen

    2012-01-01

    An important part of the declination-inclination (DI) measurement with the theodolite is to calculate the sensor parameters (horizontal and vertical misalignment, sensor offset). It is crucial to track these parameters over time, since the sensor has to be stable to give correct DI results....... The Danish Meteorological Institute and now DTU Space have formany years produced DI-fluxgate electronics and used fluxgate sensors from Pandect. Some sensors were found to be unstable due to loose ferromagnetic cores inside, i.e., the vertical misalignment changes when the sensor is turned ’upside down......’ during the DI-measurement. We have found a way to glue the ferromagnetic cores within the new sensors to make them mechanically stable. All sensors are tested very carefully before being used. Since the observed erroneous sensor offset due to loose sensor usually is extremely high, we can use a fast...

  2. Damage detection and localization algorithm using a dense sensor network of thin film sensors

    Science.gov (United States)

    Downey, Austin; Ubertini, Filippo; Laflamme, Simon

    2017-04-01

    The authors have recently proposed a hybrid dense sensor network consisting of a novel, capacitive-based thin-film electronic sensor for monitoring strain on mesosurfaces and fiber Bragg grating sensors for enforcing boundary conditions on the perimeter of the monitored area. The thin-film sensor monitors local strain over a global area through transducing a change in strain into a change in capacitance. In the case of bidirectional in-plane strain, the sensor output contains the additive measurement of both principal strain components. When combined with the mature technology of fiber Bragg grating sensors, the hybrid dense sensor network shows potential for the monitoring of mesoscale systems. In this paper, we present an algorithm for the detection, quantification, and localization of strain within a hybrid dense sensor network. The algorithm leverages the advantages of a hybrid dense sensor network for the monitoring of large scale systems. The thin film sensor is used to monitor strain over a large area while the fiber Bragg grating sensors are used to enforce the uni-directional strain along the perimeter of the hybrid dense sensor network. Orthogonal strain maps are reconstructed by assuming different bidirectional shape functions and are solved using the least squares estimator to reconstruct the planar strain maps within the hybrid dense sensor network. Error between the estimated strain maps and measured strains is extracted to derive damage detecting features, dependent on the selected shape functions. Results from numerical simulations show good performance of the proposed algorithm.

  3. Optical fibre microwire sensors

    OpenAIRE

    Brambilla, G.; Belal, Mohammad; Jung, Y.; Song, Z.; Xu, F.; Newson, T.P.; Richardson, D.J.

    2011-01-01

    This paper reviews sensing applications of optical fibre microwires and nanowires. In addition to the usual benefits of sensors based on optical fibres, these sensors are extremely compact and have fast response speeds. In this review sensors will be grouped in three categories according to their morphology: linear sensors, resonant sensors and tip sensors. While linear and resonant sensors mainly exploit the fraction of power propagating outside the microwire physical boundary, tip sensors t...

  4. The transport of 2D electrons through magnetic barriers

    Science.gov (United States)

    Kubrak, V.; Rushforth, A. W.; Neumann, A. C.; Rahman, F.; Gallagher, B. L.; Main, P. C.; Henini, M.; Marrows, C. H.; Hickey, B. J.

    2000-05-01

    We have fabricated three different types of hybrid ferromagnet-semiconductor devices. In each case, the stray field from a magnetic element on the surface of the semiconductor gives rise to a different type of inhomogeneous magnetic profile at a near-surface two-dimensional electron gas (2DEG). We investigate how these different types of magnetic barriers influence the transport properties of the 2DEG. Implications for potential applications of hybrid devices for nanomagnetometry, magnetic field sensors and spin-injection devices are discussed.

  5. Corrosion rate sensors for soil, water and concrete

    Energy Technology Data Exchange (ETDEWEB)

    Ansuini, F. [Electrochemical Devices, Inc., Albion, RI (United States); Yaffe, M. [Gamry Instruments, Inc., Willow Grove, PA (United States); Chaker, V. [Port Authority of New York and New Jersey, New York, NY (United States)

    1995-10-01

    Present concern over the condition of the infrastructure has created a need to monitor corrosion of large field structures in real time. New sensors have been developed for measuring corrosion rates of steel in concrete, underground and aqueous environments. This paper will discuss sensor designs including both the transducer and the electronics as well as field experience with these sensors in concrete.

  6. The Phoenix TECP Relative Humidity Sensor: Revised Results

    Science.gov (United States)

    Zent, Aaron

    2014-01-01

    The original calibration function of the RH sensor on the Phoenix mission's Thermal and Electrical Conductivity Sensor (TECP), has been revised to correct the erroneously-published original calibration equation, to demonstrate the value of this unique data set, and to improve characterization of H2O exchange between the martian regolith and atmosphere. TECP returned two data streams, the temperature of the electronics analog board (Tb) and the digital 12-bit output of the RH sensor (DN), both of which are required to uniquely specify the H2O abundance. Because the original flight instrument calibration was performed against a pair of hygrometers that measured frost point (Tf), the revised calibration equation is also cast in terms of frost point. The choice of functional form for the calibration function is minimally constrained. A series of profiles across the calibration data cloud at constant DN and Tb does not reveal any evidence of a complex functional form. Therefore, a series of polynomials in both DN and Tb was investigated, along with several non-linear functions of DN and Tb.

  7. Diurnal variations of the ionospheric electron density height profiles over Irkutsk: Comparison of the incoherent scatter radar measurements, GSM TIP simulations and IRI predictions

    Science.gov (United States)

    Zherebtsov, G. A.; Ratovsky, K. G.; Klimenko, M. V.; Klimenko, V. V.; Medvedev, A. V.; Alsatkin, S. S.; Oinats, A. V.; Lukianova, R. Yu.

    2017-07-01

    The long-duration continuous Irkutsk incoherent scatter radar (ISR) measurements allowed us to obtain the monthly averaged height-diurnal variations of the electron density in the 180-600 km altitudinal range for 4 four seasons (winter, spring, summer, autumn) and for two solar activity levels (low and moderate). Considering these electron density variations as ;quiet ionosphere patterns; we compared them with the Global Self-consistent Model of the Thermosphere, Ionosphere and Protonosphere (GSM TIP) simulations and the International Reference Ionosphere (IRI) predictions. It was found that some observational features revealed from the ISR measurements are reproduced nicely by both the theoretical and empirical models, and some features agree better with the GSM TIP than with IRI. None of the models is able to reproduce a detailed multi-peak behavior of the electron density observed by ISR at ∼300 km and above for the spring and autumn under low solar activity, while for the spring the GSM TIP tends to reproduce the morning and daytime peaks at the same local times as they are seen from the ISR observations.

  8. Characteristics of flux-time profiles, temporal evolution, and spatial distribution of radiation-belt electron precipitation bursts in the upper ionosphere before great and giant earthquakes

    Directory of Open Access Journals (Sweden)

    Sergey Pulinets

    2012-04-01

    Full Text Available

    The analysis of energetic electron observations made by the DEMETER satellite reveals that radiation belt electron precipitation (RBEP bursts are observed in general several (~1-6 days before a large (M > 6.5 earthquake (EQ in the presence of broad band (~1-20 kHz VLF waves. The EBs show in general a relative peak-to-background flux increase usually < 100, they have a time duration of ~0.5 – 3 min, and their energy spectrum reach up to energies <~500 keV. The RBEP activity is observed as one, two or three EBs throughout a semi-orbit, depended on the magnetic field structure above the EQ epicenter. A statistical analysis has been made for earthquakes in Japan, which reveals a standard temporal variation of the number of EBs, which begins with an incremental rate several days before major earthquakes, and after a maximum, decreases so that the electron precipitation ceases above the epicenter. Some earthquake induced EBs were observed not only in the nightside ionosphere, but also in the dayside ionosphere.

     

  9. Electronic detectors for electron microscopy.

    Science.gov (United States)

    Faruqi, A R; McMullan, G

    2011-08-01

    Electron microscopy (EM) is an important tool for high-resolution structure determination in applications ranging from condensed matter to biology. Electronic detectors are now used in most applications in EM as they offer convenience and immediate feedback that is not possible with film or image plates. The earliest forms of electronic detector used routinely in transmission electron microscopy (TEM) were charge coupled devices (CCDs) and for many applications these remain perfectly adequate. There are however applications, such as the study of radiation-sensitive biological samples, where film is still used and improved detectors would be of great value. The emphasis in this review is therefore on detectors for use in such applications. Two of the most promising candidates for improved detection are: monolithic active pixel sensors (MAPS) and hybrid pixel detectors (of which Medipix2 was chosen for this study). From the studies described in this review, a back-thinned MAPS detector appears well suited to replace film in for the study of radiation-sensitive samples at 300 keV, while Medipix2 is suited to use at lower energies and especially in situations with very low count rates. The performance of a detector depends on the energy of electrons to be recorded, which in turn is dependent on the application it is being used for; results are described for a wide range of electron energies ranging from 40 to 300 keV. The basic properties of detectors are discussed in terms of their modulation transfer function (MTF) and detective quantum efficiency (DQE) as a function of spatial frequency.

  10. Microfluidic stretchable RF electronics.

    Science.gov (United States)

    Cheng, Shi; Wu, Zhigang

    2010-12-07

    Stretchable electronics is a revolutionary technology that will potentially create a world of radically different electronic devices and systems that open up an entirely new spectrum of possibilities. This article proposes a microfluidic based solution for stretchable radio frequency (RF) electronics, using hybrid integration of active circuits assembled on flex foils and liquid alloy passive structures embedded in elastic substrates, e.g. polydimethylsiloxane (PDMS). This concept was employed to implement a 900 MHz stretchable RF radiation sensor, consisting of a large area elastic antenna and a cluster of conventional rigid components for RF power detection. The integrated radiation sensor except the power supply was fully embedded in a thin elastomeric substrate. Good electrical performance of the standalone stretchable antenna as well as the RF power detection sub-module was verified by experiments. The sensor successfully detected the RF radiation over 5 m distance in the system demonstration. Experiments on two-dimensional (2D) stretching up to 15%, folding and twisting of the demonstrated sensor were also carried out. Despite the integrated device was severely deformed, no failure in RF radiation sensing was observed in the tests. This technique illuminates a promising route of realizing stretchable and foldable large area integrated RF electronics that are of great interest to a variety of applications like wearable computing, health monitoring, medical diagnostics, and curvilinear electronics.

  11. Temperature Modulation of a Catalytic Gas Sensor

    Directory of Open Access Journals (Sweden)

    Eike Brauns

    2014-10-01

    Full Text Available The use of catalytic gas sensors usually offers low selectivity, only based on their different sensitivities for various gases due to their different heats of reaction. Furthermore, the identification of the gas present is not possible, which leads to possible misinterpretation of the sensor signals. The use of micro-machined catalytic gas sensors offers great advantages regarding the response time, which allows advanced analysis of the sensor response. By using temperature modulation, additional information about the gas characteristics can be measured and drift effects caused by material shifting or environmental temperature changes can be avoided. In this work a miniaturized catalytic gas sensor which offers a very short response time (<150 ms was developed. Operation with modulated temperature allows analysis of the signal spectrum with advanced information content, based on the Arrhenius approach. Therefore, a high-precise electronic device was developed, since theory shows that harmonics induced by the electronics must be avoided to generate a comprehensible signal.

  12. An Observation Capability Metadata Model for EO Sensor Discovery in Sensor Web Enablement Environments

    Directory of Open Access Journals (Sweden)

    Chuli Hu

    2014-10-01

    Full Text Available Accurate and fine-grained discovery by diverse Earth observation (EO sensors ensures a comprehensive response to collaborative observation-required emergency tasks. This discovery remains a challenge in an EO sensor web environment. In this study, we propose an EO sensor observation capability metadata model that reuses and extends the existing sensor observation-related metadata standards to enable the accurate and fine-grained discovery of EO sensors. The proposed model is composed of five sub-modules, namely, ObservationBreadth, ObservationDepth, ObservationFrequency, ObservationQuality and ObservationData. The model is applied to different types of EO sensors and is formalized by the Open Geospatial Consortium Sensor Model Language 1.0. The GeosensorQuery prototype retrieves the qualified EO sensors based on the provided geo-event. An actual application to flood emergency observation in the Yangtze River Basin in China is conducted, and the results indicate that sensor inquiry can accurately achieve fine-grained discovery of qualified EO sensors and obtain enriched observation capability information. In summary, the proposed model enables an efficient encoding system that ensures minimum unification to represent the observation capabilities of EO sensors. The model functions as a foundation for the efficient discovery of EO sensors. In addition, the definition and development of this proposed EO sensor observation capability metadata model is a helpful step in extending the Sensor Model Language (SensorML 2.0 Profile for the description of the observation capabilities of EO sensors.

  13. Determination of CT number and density profile of binderless, pre-treated and tannin-based Rhizophora spp. particleboards using computed tomography imaging and electron density phantom

    Science.gov (United States)

    Yusof, Mohd Fahmi Mohd; Hamid, Puteri Nor Khatijah Abdul; Bauk, Sabar; Hashim, Rokiah; Tajuddin, Abdul Aziz

    2015-04-01

    Plug density phantoms were constructed in accordance to CT density phantom model 062M CIRS using binderless, pre-treated and tannin-based Rhizophora Spp. particleboards. The Rhizophora Spp. plug phantoms were scanned along with the CT density phantom using Siemens Somatom Definition AS CT scanner at three CT energies of 80, 120 and 140 kVp. 15 slices of images with 1.0 mm thickness each were taken from the central axis of CT density phantom for CT number and CT density profile analysis. The values were compared to water substitute plug phantom from the CT density phantom. The tannin-based Rhizophora Spp. gave the nearest value of CT number to water substitute at 80 and 120 kVp CT energies with χ2 value of 0.011 and 0.014 respectively while the binderless Rhizphora Spp. gave the nearest CT number to water substitute at 140 kVp CT energy with χ2 value of 0.023. The tannin-based Rhizophora Spp. gave the nearest CT density profile to water substitute at all CT energies. This study indicated the suitability of Rhizophora Spp. particleboard as phantom material for the use in CT imaging studies.

  14. Determination of CT number and density profile of binderless, pre-treated and tannin-based Rhizophora spp. particleboards using computed tomography imaging and electron density phantom

    Energy Technology Data Exchange (ETDEWEB)

    Yusof, Mohd Fahmi Mohd, E-mail: mfahmi@usm.my; Hamid, Puteri Nor Khatijah Abdul; Tajuddin, Abdul Aziz [School of Physics, Universiti Sains Malaysia, 11800 Penang (Malaysia); Bauk, Sabar [School of Distance Education, Universiti Sains Malaysia, 11800 Penang (Malaysia); Hashim, Rokiah [School of Industrial Technologies, Universiti Sains Malaysia, 11800 Penang (Malaysia)

    2015-04-29

    Plug density phantoms were constructed in accordance to CT density phantom model 062M CIRS using binderless, pre-treated and tannin-based Rhizophora Spp. particleboards. The Rhizophora Spp. plug phantoms were scanned along with the CT density phantom using Siemens Somatom Definition AS CT scanner at three CT energies of 80, 120 and 140 kVp. 15 slices of images with 1.0 mm thickness each were taken from the central axis of CT density phantom for CT number and CT density profile analysis. The values were compared to water substitute plug phantom from the CT density phantom. The tannin-based Rhizophora Spp. gave the nearest value of CT number to water substitute at 80 and 120 kVp CT energies with χ{sup 2} value of 0.011 and 0.014 respectively while the binderless Rhizphora Spp. gave the nearest CT number to water substitute at 140 kVp CT energy with χ{sup 2} value of 0.023. The tannin-based Rhizophora Spp. gave the nearest CT density profile to water substitute at all CT energies. This study indicated the suitability of Rhizophora Spp. particleboard as phantom material for the use in CT imaging studies.

  15. Pressure sensor

    Science.gov (United States)

    Mee, David K.; Ripley, Edward B.; Nienstedt, Zachary C.; Nienstedt, Alex W.; Howell, Jr., Layton N.

    2015-09-29

    Disclosed is a passive, in-situ pressure sensor. The sensor includes a sensing element having a ferromagnetic metal and a tension inducing mechanism coupled to the ferromagnetic metal. The tension inducing mechanism is operable to change a tensile stress upon the ferromagnetic metal based on a change in pressure in the sensing element. Changes in pressure are detected based on changes in the magnetic switching characteristics of the ferromagnetic metal when subjected to an alternating magnetic field caused by the change in the tensile stress. The sensing element is embeddable in a closed system for detecting pressure changes without the need for any penetrations of the system for power or data acquisition by detecting changes in the magnetic switching characteristics of the ferromagnetic metal caused by the tensile stress.

  16. Electronics pocket book

    CERN Document Server

    Parr, E A

    1981-01-01

    Electronics Pocket Book, Fourth Edition is a nonmathematical presentation of the many varied topics covered by electronics. The book tackles electron physics, electronic components (i.e. resistors, capacitors, and conductors), integrated circuits, and the principles of a.c. and d.c. amplifiers. The text also discusses oscillators, digital circuits, digital computers, and optoelectronics (i.e., sensors, emitters, and devices that utilize light). Communications (such as line and radio communications, transmitters, receivers, and digital techniques); the principles and examples of servosystems; a

  17. A tactile sensor using a conductive graphene-sponge composite

    Science.gov (United States)

    Chun, Sungwoo; Hong, Ahyoung; Choi, Yeonhoi; Ha, Chunho; Park, Wanjun

    2016-04-01

    For sensors that emulate human tactile perception, we suggest a simple method for fabricating a highly sensitive force sensor using a conductive polyurethane sponge where graphene flakes are self-assembled into the porous structure of the sponge. The complete sensor device shows a sensitive and reliable detection response for a broad range of pressure and dynamic pressure that correspond to human tactile perception. Sensitivity of the sensor to detect vibration is also confirmed with vertical actuations due to slipping over micro-scale ridge structures attached on the sensors. Based on the sensor's ability to detect both pressure and vibration, the sensor can be utilized as a flexible tactile sensor.For sensors that emulate human tactile perception, we suggest a simple method for fabricating a highly sensitive force sensor using a conductive polyurethane sponge where graphene flakes are self-assembled into the porous structure of the sponge. The complete sensor device shows a sensitive and reliable detection response for a broad range of pressure and dynamic pressure that correspond to human tactile perception. Sensitivity of the sensor to detect vibration is also confirmed with vertical actuations due to slipping over micro-scale ridge structures attached on the sensors. Based on the sensor's ability to detect both pressure and vibration, the sensor can be utilized as a flexible tactile sensor. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr00774k

  18. Sol-Gel Thin Films for Plasmonic Gas Sensors

    Directory of Open Access Journals (Sweden)

    Enrico Della Gaspera

    2015-07-01

    Full Text Available Plasmonic gas sensors are optical sensors that use localized surface plasmons or extended surface plasmons as transducing platform. Surface plasmons are very sensitive to dielectric variations of the environment or to electron exchange, and these effects have been exploited for the realization of sensitive gas sensors. In this paper, we review our research work of the last few years on the synthesis and the gas sensing properties of sol-gel based nanomaterials for plasmonic sensors.

  19. A multi-sensor autonomous platform for fast ocean observation studies

    Digital Repository Service at National Institute of Oceanography (India)

    Afzulpurkar, S.; Navelkar, G.S.; Desa, E.; Madhan, R.; Dabholkar, N.A.; Prabhudesai, S.P.; Mascarenhas, A.A.M.Q.; Maurya, P.

    the center of gravity (CG) and center of buoyancy (CB) ensuring that the profiler body is always vertical in water. This has been achieved by placing the heavy batteries and other subsystems in the lower half while the lighter electronics and system... sensors are placed in the top half. A net buoyancy is built in the design that makes AVP to float up when no power is applied. Typically this is adjusted to about 400 gm and is sufficient for all operations for current configuration . Any changes need...

  20. LYNX: An unattended sensor system for detection of gamma-ray and neutron emissions from special nuclear materials

    Energy Technology Data Exchange (ETDEWEB)

    Runkle, Robert C.; Myjak, Mitchell J.; Kiff, Scott D.; Sidor, Daniel E.; Morris, Scott J.; Rohrer, John S.; Jarman, Kenneth D.; Pfund, David M.; Todd, Lindsay C.; Bowler, Ryan S.; Mullen, Crystal A.

    2009-01-21

    This manuscript profiles an unattended and fully autonomous detection system sensitive to gamma-ray and neutron emissions from special nuclear material. The LYNX design specifically targets applications that require radiation detection capabilities but possess little or no infrastructure. In these settings, users need the capability to deploy sensors for extended periods of time that analyze whatever signal-starved data can be captured, since little or no control may be exerted over measurement conditions. The fundamental sensing elements of the LYNX system are traditional NaI(Tl) and 3He detectors. The new developments reported here center on two themes: low-power electronics and computationally simple analysis algorithms capable of discriminating gamma-ray signatures indicative of special nuclear materials from those of naturally occurring radioactive material. Incorporating tripwire-detection algorithms based on gamma-ray spectral signatures into a low-power electronics package significantly improves performance in environments where sensors encounter nuisance sources.