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1

Temperature measuring device  

SciTech Connect

Systems and methods are described for a wireless instrumented silicon wafer that can measure temperatures at various points and transmit those temperature readings to an external receiver. The device has particular utility in the processing of semiconductor wafers, where it can be used to map thermal uniformity on hot plates, cold plates, spin bowl chucks, etc. without the inconvenience of wires or the inevitable thermal perturbations attendant with them.

Lauf, R.J.; Bible, D.W.; Sohns, C.W.

1999-10-19

2

Noncontact temperature pattern measuring device  

NASA Technical Reports Server (NTRS)

This invention relates to a noncontact imagine pyrometer system for obtaining the true temperature image of a given substance in a contactless fashion without making assumptions about localized emissivity of the substance or the uniformity of the temperature distribution. Such a contactless temperature imaging system has particular application in the study and production of many materials where the physical contact required to make a conventional temperature measurement drastically effects or contaminates the physical process being observed. Two examples where accurate temperature profiles are of critical interest are: (1) the solid-liquid phase change interface in the production of electronic materials and (2) metastable materials in the undercooling region. The apparent novelty resides in the recognition that an active pyrometer system may be advantageously adapted to perform contactless temperature imaging so that an accurate temperature profile can be obtained.

Elleman, D. D. (inventor); Allen, J. L. (inventor); Lee, M. C. (inventor)

1987-01-01

3

Noncontact temperature pattern measuring device  

NASA Technical Reports Server (NTRS)

Laser pyrometer techniques are utilized to accurately image a true temperature distribution on a given target without touching the target and without knowing the localized emissivity of the target. The pyrometer utilizes a very high definition laser beam and photodetector, both having a very narrow focus. The pyrometer is mounted in a mechanism designed to permit the pyrometer to be aimed and focused at precise localized points on the target surface. The pyrometer is swept over the surface area to be imaged, temperature measurements being taken at each point of focus.

Elleman, Daniel D. (inventor); Allen, James L. (inventor); Lee, Mark C. (inventor)

1989-01-01

4

46 CFR 154.1340 - Temperature measuring devices.  

Code of Federal Regulations, 2012 CFR

...3) Each device must show the temperature continuously or at regular intervals...in the wheelhouse before the temperature of the steel of the adjacent hull structure is cooled below the lowest temperature allowed for the steel...

2012-10-01

5

46 CFR 154.1340 - Temperature measuring devices.  

Code of Federal Regulations, 2011 CFR

...3) Each device must show the temperature continuously or at regular intervals...in the wheelhouse before the temperature of the steel of the adjacent hull structure is cooled below the lowest temperature allowed for the steel...

2011-10-01

6

46 CFR 154.1340 - Temperature measuring devices.  

Code of Federal Regulations, 2010 CFR

...3) Each device must show the temperature continuously or at regular intervals...in the wheelhouse before the temperature of the steel of the adjacent hull structure is cooled below the lowest temperature allowed for the steel...

2010-10-01

7

46 CFR 154.1340 - Temperature measuring devices.  

Code of Federal Regulations, 2013 CFR

...3) Each device must show the temperature continuously or at regular intervals...in the wheelhouse before the temperature of the steel of the adjacent hull structure is cooled below the lowest temperature allowed for the steel...

2013-10-01

8

Improvement of the operation rate of medical temperature measuring devices  

NASA Astrophysics Data System (ADS)

A method of reducing measuring time of temperature measurements of biological objects based on preheating the resistance temperature detector (RTD) up to the temperature close to the temperature to be measured, is proposed. It has been found that at the same measuring time, the preheating allows to decrease the measurement error by a factor of 5 to 45 over the temperature range of 35-41?. The measurement time is reduced by 1.6-4 times over this range, keeping the same value of the measurement error.

Hotra, O.; Boyko, O.; Zyska, T.

2014-08-01

9

Liquid crystal imaging for temperature measurement of electronic devices  

Microsoft Academic Search

The liquid crystal imaging (LCI) technique has been shown to be a viable method for part level temperature measurement. The steps necessary to develop this capability and its sensitivity to various parameters are discussed and highlighted. Comparison of LCI and point measurement showed that high accuracy can be achieved with this method. The spatial resolution which plays a critical role

Kaveh Azar; John R. Benson; Vincent P. Manno

1991-01-01

10

Silicon device performance measurements to support temperature range enhancement  

NASA Technical Reports Server (NTRS)

The results of the NPN bipolar transistor (BJT) (2N6023) breakdown voltage measurements were analyzed. Switching measurements were made on the NPN BJT, the insulated gate bipolar transistor (IGBT) (TA9796) and the N-channel metal oxide semiconductor field effect transistor (MOSFET) (RFH75N05E). Efforts were also made to build a H-bridge inverter. Also discussed are the plans that have been made to do life testing on the devices, to build an inductive switching test circuit and to build a dc/dc switched mode converter.

Johnson, R. Wayne; Askew, Ray; Bromstead, James; Weir, Bennett

1991-01-01

11

Use of a Temperature Gradient Measuring Device in Monitoring of Diabetic and Critically Ill Patients  

Microsoft Academic Search

A device realizing the simultaneous measure of the central body temperature (Tc), the superficial one (Ts) and their difference (Dt), was proposed for permanent energetic balance evaluation in humans. A program was elaborated to command the intravenous delivery of insulin by a pump depending on the value and trends of Dt. The use of this device for monitoring of decompensated

V. Coulic; V. Novikov; J. Devriendt; C. Gillet; A. Bodson; E. DeKoster

2007-01-01

12

Silicon device performance measurements to support temperature range enhancement  

NASA Technical Reports Server (NTRS)

Testing of the metal oxide semiconductor (MOS)-controlled thyristor (MCT) has uncovered a failure mechanism at elevated temperature. The failure appears to be due to breakdown of the gate oxide. Further testing is underway to verify the failure mode. Higher current level inverters were built to demonstrate 200 C operation of the N-MOSFET's and insulated-gate-bipolar transistors (IGBT's) and for life testing. One MOSFET failed early in testing. The origin of this failure is being studied. No IGBT's have failed. A prototype 28-to-42 V converter was built and is being tested at room temperature. The control loop is being finalized. Temperature stable, high value (10 micro-F) capacitors appear to be the limiting factor in the design at this time. In this application, the efficiency will be lower for the IGBT version due to the large V sub(cesat) (3.5-4 V) compared to the input voltage of 28 V. The MOSFET version should have higher efficiency; however, the MOSFET does not appear to be as robust at 200 C. Both versions are built for comparison.

Bromstead, James; Weir, Bennett; Johnson, R. Wayne; Askew, Ray

1992-01-01

13

Sublimation measurements and analysis of high temperature thermoelectric materials and devices  

NASA Technical Reports Server (NTRS)

High temperature thermoelectric device sublimation effects are compared for rare earth sulfides, selenides, and state-of-the-art Si-Ge alloys. Although rare earth calcogenides can potentially exhibit superior sublimation characteristics, the state-of-the-art Si-Ge alloy with silicon nitride sublimation-inhibitive coating has been tested to 1000 C. Attention is given to the ceramic electrolyte cells, forming within electrical and thermal insulation, which affect leakage conductance measurements in Si-Ge thermoelectric generators.

Shields, V.; Noon, L.

1983-01-01

14

A New Low Temperature Device for High Resolution, In Situ Measurement and Control of Submicron Gaps  

Microsoft Academic Search

We have developed a device to investigate finite-size scaling of the thermal expansion coefficient in liquid helium near the lambda transition. Motivated by the need for a range of well known, uniform, sub-micron gaps with constant surface conditions, we have built a variable-gap parallel-plate capacitor that can be adjusted in situ. We measure the gap at three points using laser

Tamar More; Clifford Dax; Joseph Niemela; Gary Ihas

2000-01-01

15

A robust and well shielded thermal conductivity device for low temperature measurements  

NASA Astrophysics Data System (ADS)

We present a compact mechanically robust thermal conductivity measurement apparatus for measurements at low temperatures (<1 K) and high magnetic fields on small high-purity single crystal samples. A high-conductivity copper box is used to enclose the sample and all the components. The box provides protection for the thermometers, heater, and most importantly the sample increasing the portability of the mount. In addition to physical protection, the copper box is also effective at shielding radio frequency electromagnetic interference and thermal radiation, which is essential for low temperature measurements. A printed circuit board in conjunction with a braided ribbon cable is used to organize the delicate wiring and provide mechanical robustness.

Toews, W. H.; Hill, R. W.

2014-04-01

16

Localized Heating on Silicon Field Effect Transistors: Device Fabrication and Temperature Measurements in Fluid  

PubMed Central

We demonstrate electrically addressable localized heating in fluid at the dielectric surface of silicon-on-insulator field-effect transistors via radio-frequency Joule heating of mobile ions in the Debye layer. Measurement of fluid temperatures in close vicinity to surfaces poses a challenge due to the localized nature of the temperature profile. To address this, we developed a localized thermometry technique based on the fluorescence decay rate of covalently attached fluorophores to extract the temperature within 2 nm of any oxide surface. We demonstrate precise spatial control of voltage dependent temperature profiles on the transistor surfaces. Our results introduce a new dimension to present sensing systems by enabling dual purpose silicon transistor-heaters that serve both as field effect sensors as well as temperature controllers that could perform localized bio-chemical reactions in Lab on Chip applications. PMID:19967115

Elibol, Oguz H.; Reddy, Bobby; Nair, Pradeep R.; Dorvel, Brian; Butler, Felice; Ahsan, Zahab; Bergstrom, Donald E.; Alam, Muhammad A.; Bashir, Rashid

2010-01-01

17

High spatial resolution micro-Raman temperature measurements of nitride devices (FETs and light emitters)  

NASA Astrophysics Data System (ADS)

The cover picture of the present issue of physica status solidi (a) is a temperature map of a AlGaN/GaN heterostructure field effect transistor (HFET) obtained using micro-Raman spectroscopy. The inset shows a photograph of the device with source (S), gate (G) and drain (D) positions marked. The paper by M. Kuball et al. [1] is an invited presentation from the International Workshop on Nitride Semiconductors (IWN 2004).In the Rapid Research Letter by B. Lamprecht et al. [2] the authors report on the successful fabrication and characterization of working organic photodiodes deposited on ordinary newspaper sheets as an example for a flexible and very rough substrate with unfortunate mechanical properties.

Kuball, M.; Pomeroy, J. W.; Rajasingam, S.; Sarua, A.; Uren, M. J.; Martin, T.; Lell, A.; Hrle, V.

2005-04-01

18

Portable emittance measurement device  

SciTech Connect

In Institute for Theoretical and Experimental Physics (ITEP) the portable emittance measurements device is developed. It provides emittance measurements both with ''pepper-pot'' and ''two slits'' methods. Depending on the method of measurements, either slits or pepper-pot mask with scintillator are mounted on the two activators and are installed in two standard Balzer's cross chamber with CF-100 flanges. To match the angle resolution for measured beam, the length of the stainless steel pipe between two crosses changes is adjusted. The description of the device and results of emittance measurements at the ITEP ion source test bench are presented.

Liakin, D.; Seleznev, D.; Orlov, A.; Kuibeda, R.; Kropachev, G.; Kulevoy, T.; Yakushin, P. [Institute for Theoretical and Experimental Physics, Moscow 117218 (Russian Federation)

2010-02-15

19

Measuring Temperature  

NSDL National Science Digital Library

This is a lesson about measuring temperature. Learners will apply their knowledge of how temperature affects matter to understand how a thermometer works. They then read about the history of the thermometer and the temperature scales that make the information from the thermometer meaningful. The lesson models scientific inquiry using the 5E instructional model and includes teacher notes, prerequisite concepts, common misconceptions, student journal and reading. This is lesson 6 in the Astro-Venture Astronomy Unit. The lessons are designed for educators to use in conjunction with the Astro-Venture multimedia modules.

20

Human performance measuring device  

NASA Technical Reports Server (NTRS)

Complex coordinator, consisting of operator control console, recorder, subject display panel, and limb controls, measures human performance by testing perceptual and motor skills. Device measures psychophysiological functions in drug and environmental studies, and is applicable to early detection of psychophysiological body changes.

Michael, J.; Scow, J.

1970-01-01

21

A Microfluidic Device with a Linear Temperature Gradient for Parallel and Combinatorial Measurements  

E-print Network

channels simultaneously. This result is exploited to rapidly obtain activation energies from catalytic as well as the determination of phase transition temperatures and activation energies from single) Fodor, S. P. A.; Read, J. L.; Pirrung, M. C.; Stryer, L.; Lu, A. T.; Solas, D. Science 1991, 251, 767

22

High temperature superconductor micro-superconducting-quantum-interference-device magnetometer for magnetization measurement of a microscale magnet  

SciTech Connect

We have developed a high temperature superconductor (HTS) micrometer-sized dc superconducting quantum interference device (SQUID) magnetometer for high field and high temperature operation. It was fabricated from YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} of 92 nm in thickness with photolithography techniques to have a hole of 4x9 {mu}m{sup 2} and 2 {mu}m wide grain boundary Josephson junctions. Combined with a three dimensional magnetic field coil system, the modulation patterns of critical current I{sub c} were observed for three different field directions. They were successfully used to measure the magnetic properties of a molecular ferrimagnetic microcrystal (23x17x13 {mu}m{sup 3}), [Mn{sub 2}(H{sub 2}O){sub 2}(CH{sub 3}COO)][W(CN){sub 8}]{center_dot}2H{sub 2}O. The magnetization curve was obtained in magnetic field up to 0.12 T between 30 and 70 K. This is the first to measure the anisotropy of hysteresis curve in the field above 0.1 T with an accuracy of 10{sup -12} J T{sup -1} (10{sup -9} emu) with a HTS micro-SQUID magnetometer.

Takeda, Keiji [Institute for Solid State Physics, University of Tokyo, Kashiwanoha 5-1-5, Kashiwa-shi, Chiba 277-8581 (Japan); Department of Chemistry, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033 (Japan); CREST, JST, Kawaguchi-shi, Saitama 332-0012 (Japan); Mori, Hatsumi [Institute for Solid State Physics, University of Tokyo, Kashiwanoha 5-1-5, Kashiwa-shi, Chiba 277-8581 (Japan); CREST, JST, Kawaguchi-shi, Saitama 332-0012 (Japan); Yamaguchi, Akira; Ishimoto, Hidehiko [Institute for Solid State Physics, University of Tokyo, Kashiwanoha 5-1-5, Kashiwa-shi, Chiba 277-8581 (Japan); Nakamura, Takayoshi [CREST, JST, Kawaguchi-shi, Saitama 332-0012 (Japan); Research Institute for Electronic Science, Hokkaido University, Kita 12 Nishi 6, Sapporo-shi, Hokkaido 060-0812 (Japan); Kuriki, Shinya [Research Institute for Electronic Science, Hokkaido University, Kita 12 Nishi 6, Sapporo-shi, Hokkaido 060-0812 (Japan); Hozumi, Toshiya; Ohkoshi, Shin-ichi [Department of Chemistry, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033 (Japan)

2008-03-15

23

Inducer Hydrodynamic Load Measurement Devices  

NASA Technical Reports Server (NTRS)

Marshall Space Flight Center (MSFC) has demonstrated two measurement devices for sensing and resolving the hydrodynamic loads on fluid machinery. The first - a derivative of the six-component wind tunnel balance - senses the forces and moments on the rotating device through a weakened shaft section instrumented with a series of strain gauges. This rotating balance was designed to directly measure the steady and unsteady hydrodynamic loads on an inducer, thereby defining both the amplitude and frequency content associated with operating in various cavitation modes. The second device - a high frequency response pressure transducer surface mounted on a rotating component - was merely an extension of existing technology for application in water. MSFC has recently completed experimental evaluations of both the rotating balance and surface-mount transducers in a water test loop. The measurement bandwidth of the rotating balance was severely limited by the relative flexibility of the device itself, resulting in an unexpectedly low structural bending mode and invalidating the higher-frequency response data. Despite these limitations, measurements confirmed that the integrated loads on the four-bladed inducer respond to both cavitation intensity and cavitation phenomena. Likewise, the surface-mount pressure transducers were subjected to a range of temperatures and flow conditions in a non-rotating environment to record bias shifts and transfer functions between the transducers and a reference device. The pressure transducer static performance was within manufacturer's specifications and dynamic response accurately followed that of the reference.

Skelley, Stephen E.; Zoladz, Thomas F.; Turner, Jim (Technical Monitor)

2002-01-01

24

Inducer Hydrodynamic Load Measurement Devices  

NASA Technical Reports Server (NTRS)

Marshall Space Flight Center (MSFC) has demonstrated two measurement devices for sensing and resolving the hydrodynamic loads on fluid machinery. The first - a derivative of the six component wind tunnel balance - senses the forces and moments on the rotating device through a weakened shaft section instrumented with a series of strain gauges. This "rotating balance" was designed to directly measure the steady and unsteady hydrodynamic loads on an inducer, thereby defining both the amplitude and frequency content associated with operating in various cavitation modes. The second device - a high frequency response pressure transducer surface mounted on a rotating component - was merely an extension of existing technology for application in water. MSFC has recently completed experimental evaluations of both the rotating balance and surface-mount transducers in a water test loop. The measurement bandwidth of the rotating balance was severely limited by the relative flexibility of the device itself, resulting in an unexpectedly low structural bending mode and invalidating the higher frequency response data. Despite these limitations, measurements confirmed that the integrated loads on the four-bladed inducer respond to both cavitation intensity and cavitation phenomena. Likewise, the surface-mount pressure transducers were subjected to a range of temperatures and flow conditions in a non-rotating environment to record bias shifts and transfer functions between the transducers and a reference device. The pressure transducer static performance was within manufacturer's specifications and dynamic response accurately followed that of the reference.

Skelley, Stephen E.; Zoladz, Thomas F.

2002-01-01

25

Temperature measurement  

MedlinePLUS

... whether or not treatment is working. A high temperature is a fever . ... recommends against using glass thermometers with mercury. The glass can ... The temperature is displayed on an easy-to-read panel. ...

26

Capacitance measuring device  

DOEpatents

A capacitance measuring circuit is provided in which an unknown capacitance is measured by comparing the charge stored in the unknown capacitor with that stored in a known capacitance. Equal and opposite voltages are repetitively simultaneously switched onto the capacitors through an electronic switch driven by a pulse generator to charge the capacitors during the ''on'' portion of the cycle. The stored charge is compared by summing discharge currents flowing through matched resistors at the input of a current sensor during the ''off'' portion of the switching cycle. The net current measured is thus proportional to the difference in value of the two capacitances. The circuit is capable of providing much needed accuracy and stability to a great variety of capacitance-based measurement devices at a relatively low cost.

Andrews, W.H. Jr.

1984-08-01

27

Temperature Measurement Aid  

NASA Technical Reports Server (NTRS)

NASA's Ames Research Center has designed a simple but medically important device--one which holds temperature probes, called thermistors, to a person's skin without affecting the characteristics of the skin segment being measured. The device improves the accuracy of skin surface temperature measurements, valuable data in health evaluation. The need for such a device was recognized in the course of life science experiments at Ames. In earlier methods, the sensing head of the temperature probe was affixed to the patient's skin by tape or elastic bands. This created a heat variance which altered skin temperature readings. The Ames-developed thermistor holder is a plastic ring with tab extensions, shown in the upper photo on the chest, arm and leg of the patient undergoing examination. The ring holds the sensing head of the temperature probe and provides firm, constant pressure between the skin and the probe. The tabs help stabilize the ring and provide attachment points for the fastening tape or bands, which do not directly touch the sensor. With this new tool, it is possible to determine more accurately the physiological effects of strenuous exercise, particularly on the treadmill. The holder is commercially available from Yellow Springs Instrument Company, Inc., Yellow Springs, Ohio, which is producing the device under a NASA patent license.

1979-01-01

28

Temperature monitoring device and thermocouple assembly therefor  

SciTech Connect

This patent describes a temperature monitoring device for measuring the temperature at a surface of a body, composed of: at least one first thermocouple and a second thermocouple; support members supporting the thermocouples for placing the first thermocouple in contact with the body surface and for maintaining the second thermocouple at a defined spacing from the body surface; and a calculating circuit connected to the thermocouples for receiving individual signals each representative of the temperature reading produced by a respective one of the first and second thermocouples and for producing a corrected temperature signal having a value which represents the temperature of the body surface and is a function of the difference between the temperature reading produced by the first thermocouple and a selected fraction of the temperature reading provided by the second thermocouple.

Grimm, N.P.; Bauer, F.I.; Bengel, T.G.; Kothmann, R.E.; Mavretish, R.S.; Miller, P.E.; Nath, R.J.; Salton, R.B.

1991-10-29

29

Temperature monitoring device and thermocouple assembly therefor  

DOEpatents

A temperature monitoring device for measuring the temperature at a surface of a body, composed of: at least one first thermocouple and a second thermocouple; support members supporting the thermocouples for placing the first thermocouple in contact with the body surface and for maintaining the second thermocouple at a defined spacing from the body surface; and a calculating circuit connected to the thermocouples for receiving individual signals each representative of the temperature reading produced by a respective one of the first and second thermocouples and for producing a corrected temperature signal having a value which represents the temperature of the body surface and is a function of the difference between the temperature reading produced by the first thermocouple and a selected fraction of the temperature reading provided by the second thermocouple.

Grimm, Noel P. (Monroeville, PA); Bauer, Frank I. (Perry Township, Lawrence County, PA); Bengel, Thomas G. (Plum Boro, PA); Kothmann, Richard E. (Churchill Boro, PA); Mavretish, Robert S. (New Stanton, PA); Miller, Phillip E. (Greensburg, PA); Nath, Raymond J. (Murrysville, PA); Salton, Robert B. (Plum Boro, PA)

1991-01-01

30

Measurements of ion temperature and flow of pulsed plasmas produced by a magnetized coaxial plasma gun device using an ion Doppler spectrometer  

NASA Astrophysics Data System (ADS)

It is important to know surface damage characteristics of plasma-facing component materials during transient heat and particle loads such as type I ELMs. A magnetized coaxial plasma gun (MCPG) device has been used as transient heat and particle source in ELM simulation experiments. Characteristics of pulsed plasmas produced by the MCPG device play an important role for the plasma material interaction. In this study, ion temperature and flow velocity of pulsed He plasmas were measured by an ion Doppler spectrometer (IDS). The IDS system consists of a light collection system including optical fibers, 1m-spectrometer and a 16 channel photomultiplier tube (PMT) detector. The IDS system measures the width and Doppler shift of HeII (468.58 nm) emission line with the time resolution of 1 ?s. The Doppler broadened and shifted spectra were measured with 45 and 135 degree angles with respect to the plasmoid traveling direction. The observed emission line profile was represented by sum of two Gaussian components to determine the temperature and flow velocity. The minor component at around the wavelength of zero-velocity was produced by the stationary plasma. As the results, the ion velocity and temperature were 68 km/s and 19 eV, respectively. Thus, the He ion flow energy is 97 eV. The observed flow velocity agrees with that measured by a time of flight technique.

Kitagawa, Y.; Sakuma, I.; Iwamoto, D.; Kikuchi, Y.; Fukumoto, N.; Nagata, M.

2012-10-01

31

Jaw bite force measurement device.  

PubMed

We describe a cost-effective device that uses an off-the-shelf force transducer to measure patient bite force as a diagnostic aid in determining dental implant size, number of implants, and prosthetic design for restoring partial edentulism. The main advantages of the device are its accuracy, simplicity, modularity, ease of manufacturing, and low cost. PMID:20822470

Flanagan, Dennis; Ilies, Horea; O'Brien, Brendan; McManus, Anne; Larrow, Beau

2012-08-01

32

Mirror Measurement Device  

NASA Technical Reports Server (NTRS)

A Small Business Innovation Research (SBIR) contract led to a commercially available instrument used to measure the shape profile of mirror surfaces in scientific instruments. Bauer Associates, Inc.'s Bauer Model 200 Profilometer is based upon a different measurement concept. The local curvature of the mirror's surface is measured at many points, and the collection of data is computer processed to yield the desired shape profile. (Earlier profilometers are based on the principle of interferometry.) The system is accurate and immune to problems like vibration and turbulence. Two profilometers are currently marketed, and a third will soon be commercialized.

1992-01-01

33

Evaluation and improvement in the accuracy of a charge-coupled-device-based pyrometer for temperature field measurements of continuous casting billets.  

PubMed

This paper presents a radiometric high-temperature field measurement model based on a charge-coupled-device (CCD). According to the model, an intelligent CCD pyrometer with a digital signal processor as the core is developed and its non-uniformity correction algorithm for reducing the differences in accuracy between individual pixel sensors is established. By means of self-adaptive adjustment for the light-integration time, the dynamic range of the CCD is extended and its accuracy in low-temperature range is improved. The non-uniformity correction algorithm effectively reduces the accuracy differences between different pixel sensors. The performance of the system is evaluated through a blackbody furnace and an integrating sphere, the results of which show that the dynamic range of 400 K is obtained and the accuracy in low temperature range is increased by 7 times compared with the traditional method based on the fixed light-integration time. In addition, the differences of accuracy between the on-axis pixel and the most peripheral pixels are decreased from 19.1 K to 2.8 K. Therefore, this CCD pyrometer ensures that the measuring results of all pixels tend to be equal-accuracy distribution across the entire measuring ranges. This pyrometric system has been successfully applied to the temperature field measurements in continuous casting billets. PMID:23822369

Bai, Haicheng; Xie, Zhi; Zhang, Yuzhong; Hu, Zhenwei

2013-06-01

34

Angular displacement measuring device  

NASA Technical Reports Server (NTRS)

A system for measuring the angular displacement of a point of interest on a structure, such as aircraft model within a wind tunnel, includes a source of polarized light located at the point of interest. A remote detector arrangement detects the orientation of the plane of the polarized light received from the source and compares this orientation with the initial orientation to determine the amount or rate of angular displacement of the point of interest. The detector arrangement comprises a rotating polarizing filter and a dual filter and light detector unit. The latter unit comprises an inner aligned filter and photodetector assembly which is disposed relative to the periphery of the polarizer so as to receive polarized light passing the polarizing filter and an outer aligned filter and photodetector assembly which receives the polarized light directly, i.e., without passing through the polarizing filter. The purpose of the unit is to compensate for the effects of dust, fog and the like. A polarization preserving optical fiber conducts polarized light from a remote laser source to the point of interest.

Seegmiller, H. Lee B. (inventor)

1992-01-01

35

Direct temperature mapping of nanoscale plasmonic devices.  

PubMed

Side by side with the great advantages of plasmonics in nanoscale light confinement, the inevitable ohmic loss results in significant joule heating in plasmonic devices. Therefore, understanding optical-induced heat generation and heat transport in integrated on-chip plasmonic devices is of major importance. Specifically, there is a need for in situ visualization of electromagnetic induced thermal energy distribution with high spatial resolution. This paper studies the heat distribution in silicon plasmonic nanotips. Light is coupled to the plasmonic nanotips from a silicon nanowaveguide that is integrated with the tip on chip. Heat is generated by light absorption in the metal surrounding the silicon nanotip. The steady-state thermal distribution is studied numerically and measured experimentally using the approach of scanning thermal microscopy. It is shown that following the nanoscale heat generation by a 10 mW light source within a silicon photonic waveguide the temperature in the region of the nanotip is increased by ? 15 C compared with the ambient temperature. Furthermore, we also perform a numerical study of the dynamics of the heat transport. Given the nanoscale dimensions of the structure, significant heating is expected to occur within the time frame of picoseconds. The capability of measuring temperature distribution of plasmonic structures at the nanoscale is shown to be a powerful tool and may be used in future applications related to thermal plasmonic applications such as control heating of liquids, thermal photovoltaic, nanochemistry, medicine, heat-assisted magnetic memories, and nanolithography. PMID:24422562

Desiatov, Boris; Goykhman, Ilya; Levy, Uriel

2014-02-12

36

Edge turbulence measurements in toroidal fusion devices  

Microsoft Academic Search

This paper reviews measurements of edge plasma turbulence in toroidal magnetic fusion devices with an emphasis on recent results in tokamaks. The dominant feature of edge turbulence is a high level of broadband density fluctuations with a relative amplitude deltan\\/n ~ 5 100%, accompanied by large potential and electron temperature fluctuations. The frequency range of this turbulence is ~10 kHz

S. J. Zweben; J. A. Boedo; O. Grulke; C. Hidalgo; B. La Bombard; R. J. Maqueda; P. Scarin; J. L. Terry

2007-01-01

37

Beta ray flux measuring device  

DOEpatents

A beta ray flux measuring device in an activated member in-core instrumentation system for pressurized water reactors. The device includes collector rings positioned about an axis in the reactor's pressure boundary. Activated members such as hydroballs are positioned within respective ones of the collector rings. A response characteristic such as the current from or charge on a collector ring indicates the beta ray flux from the corresponding hydroball and is therefore a measure of the relative nuclear power level in the region of the reactor core corresponding to the specific exposed hydroball within the collector ring.

Impink, Jr., Albert J. (Murrysville, PA); Goldstein, Norman P. (Murrysville, PA)

1990-01-01

38

Devices and methods to measure H2 and CO2 concentrations in gases released from soils and low temperature fumaroles in volcanic areas  

NASA Astrophysics Data System (ADS)

Hydrogen solubility and diffusion have a great relevance to change the redox state of magmas, usually expressed by oxygen fugacity. This influences many chemical and physical properties, such as oxidation state of multivalent elements, kind and abundance of minerals and gas species. These processes change the phase ratios into the volcanic system and so the magma movement capability toward the earth surface and the eruptive dynamics. In past studies several authors (Carapezza et al., 1980; Sato et al., 1982; Sato and McGee, 1985; Wakita et al., 1980) proposed the application of the fuel cells in order to measure reducing capacity of volcanic gases. Their found some clear correlations between variation peaks and volcanic activity but a few reducing capacity changes showed no correlation with it. In this study we characterize a fuel cell device designed to measure hydrogen concentration in a gas mixture. We present test results obtained in laboratory and in field trip, carried out to verify the major interferences of others reducing gas species, commonly present in volcanic emissions, in the measurement carried out with a hydrogen fuel cell sensor. Tests were performed at controlled temperature ad pressure conditions and at air saturated pressure vapour in the cell cathode. A new device to measure simultaneously hydrogen (H2) and carbon dioxide (CO2) concentrations in soil and in low temperature fumaroles in volcanic areas was proposed. The H2-detector is a hydrogen fuel cell, whereas CO2 is measured using an I.R. spectrometer. To build a continuous monitoring station of volcanic activity both sensors were put in a case together with a data logger. Our device has 0.2 mV ppm-1 sensitivity, accuracy of 5 ppm and about 10 ppm resolution whit respect to the hydrogen concentration. These instrumental characteristics were obtained applying a 500 ohm resistor to the external circuit that represents the best compromise between sensitivity, resolution, instrumental response time, and linearity of signal. We determine the CO2 concentration in the gas mixture with an I.R. spectrometer that has a measuring range of 0-100% with accuracy of 2% of the range and response time of 10 seconds. The laboratory results confirm our hypothesis of interference between H2, H2S and CO in the full concentration range of contaminant species. Therefore, according to our studies, the assignment of the fuel cell signal output variations only to H2 variation of concentration as in past studies, without physical separation of different reducing species may be misleading. Continuous measurements and periodical measurement field trip were performed at Torre Del Filosofo site on the upper part of the Etna volcano from the end of July to the middle October 2008. In field applications, H2S was removed with a Pb(COOH)2 trap whereas CO interference was neglected because H2/CO ratios in volcanic gases are typically high. Field time-series measurements of H2 and CO2 in gases emitted by low temperature fumaroles at Torre del Filosofo site showed a close positive correlation between explosion activity and the major peaks in the hydrogen concentration.

di Martino, R. M. R.; Camarda, M.; Gurrieri, S.; Valenza, M.

2009-04-01

39

Development of a Low-Temperature Insert for Precise Magnetization Measurement below T = 2 K with a Superconducting Quantum Interference Device Magnetometer  

NASA Astrophysics Data System (ADS)

We have developed a 9-mm-diameter 3He insert for precise magnetization measurements below T = 2 K that is attachable to a commercial superconducting quantum interference device magnetometer. The insert is made from a thin-walled stainless steel pipe with an inner diameter of 6.2 mm, which determines the maximum sample size. 3He gas is condensed in the pipe, which is liquefied by 4He gas at T ?1.8 K generated by the magnetometer via the heat exchanger of a Cu vacuum jacket with an outer diameter of 8.6 mm soldered to the stainless steel pipe. The temperature of the insert is decreased to T ?0.5 K by evacuating liquid 3He using a rotary pump and then to T = 0.36 K with a sorption pump. From the diamagnetization signal of a superconducting Al chip with a mass below 0.1 mg, the magnetization resolution with the insert is confirmed to be less than 10-7 emu. To examine the performance of the insert, we measured the temperature dependence of the magnetic susceptibility and magnetization for Pr0.6La0.4Ag2In down to T = 0.4 K.

Sato, Yoshiaki; Makiyama, Shun; Sakamoto, Yasutaka; Hasuo, Tadahiko; Inagaki, Yuji; Fujiwara, Tetsuya; Suzuki, Hiroyuki S.; Matsubayashi, Kazuyuki; Uwatoko, Yoshiya; Kawae, Tatsuya

2013-10-01

40

Tory reactor temperature measurements  

Microsoft Academic Search

Declassified 26 Nov 1973. The basic problem to be dealt with was how to ; continuously measure temperatures in the active core of a reactor that was to be ; operated as a high-temperature heat exchanger with compressed air used as the ; cooling medium. Some 345 to 375 measurements were made on the Tory IIA and IIC ; reactors.

1965-01-01

41

High-temperature superconducting quantum interference device with cooled LC resonant circuit for measuring alternating magnetic fields with improved signal-to-noise ratio  

SciTech Connect

Certain applications of superconducting quantum interference devices (SQUIDs) require a magnetic field measurement only in a very narrow frequency range. In order to selectively improve the alternating-current (ac) magnetic field sensitivity of a high-temperature superconductor SQUID for a distinct frequency, a single-coil LC resonant circuit has been used. Within the liquid nitrogen bath, the coil surrounds the SQUID and couples to it inductively. Copper coils with different numbers of windings were used to cover the frequency range from <1 to nearly 100 kHz. A superconducting coil made of YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} tape conductor was also tested. With the LC circuit, the signal-to-noise ratio of measurements could be improved typically by one order of magnitude or more in a narrow frequency band around the resonance frequency exceeding a few kilohertz. The best attained equivalent magnetic field resolution was 2.5 fT/{radical}Hz at 88 kHz. The experimental findings are in good agreement with mathematical analysis of the circuit with copper coil.

Qiu Longqing; Zhang Yi; Krause, Hans-Joachim; Braginski, Alex I.; Usoskin, Alexander [Institute of Bio- and Nanosystem (IBN-2), Research Center Juelich, D-52425 Juelich (Germany) and Pohl Institute of Solid State Physics, Tongji University, Shanghai 200092 (China); Institute of Bio- and Nanosystem (IBN-2), Research Center Juelich, D-52425 Juelich (Germany); European High Temperature Superconductors GmbH and Co. KG, D-63450 Hanau (Germany)

2007-05-15

42

High-temperature superconducting quantum interference device with cooled LC resonant circuit for measuring alternating magnetic fields with improved signal-to-noise ratio.  

PubMed

Certain applications of superconducting quantum interference devices (SQUIDs) require a magnetic field measurement only in a very narrow frequency range. In order to selectively improve the alternating-current (ac) magnetic field sensitivity of a high-temperature superconductor SQUID for a distinct frequency, a single-coil LC resonant circuit has been used. Within the liquid nitrogen bath, the coil surrounds the SQUID and couples to it inductively. Copper coils with different numbers of windings were used to cover the frequency range from <1 to nearly 100 kHz. A superconducting coil made of YBa(2)Cu(3)O(7-delta) tape conductor was also tested. With the LC circuit, the signal-to-noise ratio of measurements could be improved typically by one order of magnitude or more in a narrow frequency band around the resonance frequency exceeding a few kilohertz. The best attained equivalent magnetic field resolution was 2.5 fT/radicalHz at 88 kHz. The experimental findings are in good agreement with mathematical analysis of the circuit with copper coil. PMID:17552846

Qiu, Longqing; Zhang, Yi; Krause, Hans-Joachim; Braginski, Alex I; Usoskin, Alexander

2007-05-01

43

Design parameter evaluation of a metal recoated Fiber Bragg Grating sensors for measurement of cryogenic temperature or stress in superconducting devices  

Microsoft Academic Search

There are plenty of complex physical phenomena which remain to be studied and verified experimentally for building an optimized superconducting magnet. The main problem for experimental validations is due to the unavailability of suitable sensors. This paper proposes a Fiber Bragg Gratings (FBG) sensor for this purpose which allows access to the local temperature\\/stress state. To measure the low temperature

R. Rajinikumar; M. Ser; K. G. Narayankhedkar; G. Krieg; M. D. Atrey

2009-01-01

44

Indirect Blood Pressure Measuring Device  

NASA Technical Reports Server (NTRS)

Design and performance of a blood pressure recording device for pediatric use are reported. A strain gage transducer with a copper-beryllium strip as force sensing element is used to monitor skin movements and to convert them into electrical signals proportional to those displacements. Experimental tests with this device in recording of force developed above the left femoral artery of a dog accurately produced a blood pressure curve.

Hum, L.; Cole, C. E.

1973-01-01

45

Remote IR temperature measurement for microgravity experiment  

Microsoft Academic Search

A remote temperature sensor has been developed to measure the temperature of a metal alloy in microgravity conditions, on board an automatic and sealed experimental station in the Space Shuttle. The device is composed of an optical system, that allows thermal radiation from the hot body to pass through an orifice in the oven, and focus onto an infrared detector

Ricardo Peralta-Fabi; Javier Mendieta-Jimenez

1987-01-01

46

Radiation scanning and measuring device  

SciTech Connect

A scanning device for examining an object with gamma rays with shielding for protection from radiation and protection of the mechanism from heat by a cooling jacket formed by spaced plates around the object. The shielding is formed by a pair of shutter-halves forming a lead shutter with mechanism to move the shutter-halves toward and away from each other and one of the shutter-halves mounted on a rotating drum which also carries three gamma ray sources. Gamma ray detectors are mounted in a circle concentric and outside the circle of the sources.

Tatham, E. J.; Clymer, J. C.; Hoffman, C. D.; Kravits, R.

1985-04-16

47

Characteristics of III-V Semiconductor Devices at High Temperature  

NASA Technical Reports Server (NTRS)

This paper presents the development of III-V based pseudomorphic high electron mobility transistors (PHEMT's) designed to operate over the temperature range 77 to 473 K (-196 to 200 C). These devices have a pseudomorphic undoped InGaAs channel that is sandwiched between an AlGaAs spacer and a buffer layer; gate widths of 200, 400, 1600, and 3200 micrometers; and a gate length of 2 micrometers. Measurements were performed at both room temperature and 473 K (200 C) and show that the drain current decreases by 30 percent and the gate current increases to about 9 microns A (at a reverse bias of -1.5 V) at the higher temperature. These devices have a maximum DC power dissipation of about 4.5 W and a breakdown voltage of about 16 V.

Simons, Rainee N.; Young, Paul G.; Taub, Susan R.; Alterovitz, Samuel A.

1994-01-01

48

High temperature solder device for flat cables  

NASA Technical Reports Server (NTRS)

A high temperature solder device for flat cables includes a microwelder, an anvil which acts as a heat sink and supports a flexible flat ribbon cable that is to be connected to a multiple pin connector. The microwelder is made from a modified commercially available resistance welding machine such as the Split Tip Electrode microwelder by Weltek, which consists of two separate electrode halves with a removable dielectric spacer in between. The microwelder is not used to weld the items together, but to provide a controlled compressive force on, and energy pulse to, a solder preform placed between a pin of the connector and a conductor of the flexible flat ribbon cable. When the microwelder is operated, an electric pulse will flow down one electrode, through the solder preform and back up the other electrode. This pulse of electrical energy will cause the solder preform to heat up and melt, joining the pin and conductor.

Haehner, Carl L. (inventor)

1992-01-01

49

21 CFR 882.1560 - Skin potential measurement device.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Skin potential measurement device. 882.1560 ...Diagnostic Devices 882.1560 Skin potential measurement device. (a) Identification. A skin potential measurement device is a general...

2011-04-01

50

21 CFR 882.1560 - Skin potential measurement device.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Skin potential measurement device. 882.1560 ...Diagnostic Devices 882.1560 Skin potential measurement device. (a) Identification. A skin potential measurement device is a general...

2010-04-01

51

[Simultaneous measurement of the kinetics of disinfection temperatures using pyoptometer techniques in the capillary system of a new type of inhalation device].  

PubMed

Due to patient collectives with chronic respiratory diseases it is important to avoid the transfer of pathogenic as well as opportunistic nosocomial infective agents during inhalation therapy. According to the literature in clinical practice the colonization with gram negative bacteria constitutes a hygienically relevant hazard. We have tested an inhaler whose patient-side inhalation insert can be autoclaved and whose other parts, whether filled with water or air, can be partially disinfected through a programmable hot air stream. In simultaneous measurements of the disinfecting temperature at four positions of the basic appliance the time-dependent kinetics could be shown for different conditions of thermoisolation and flow of the volume stream by means of pyoptometer thermal probes. The pyoptometer probe technique, which is based on a change of the wave length of laser light in a gallium crystal of 0.5 mm diameter, allows temperature measurements practically without delay. As the connection from the probe crystal to the laser sensor is made by glass fibre cable, the measuring lead remains unaffected by galvanic-technical and secondary thermal effects. It could be demonstrated that the required disinfection temperature in the capillary system of the entire inhaler was reached within 17 min even under worst case conditions (studies of the longest capillary, water replenishment of the entire system before disinfection). Compared to former systems the evaluated apparatus constitutes thus a significant progress in the development of inhalation systems. PMID:8011062

Seipp, H M

1994-04-01

52

Introducing Temperature Measurement  

NSDL National Science Digital Library

In this activity, students will learn how to read a Celsius-scale thermometer, associate weather conditions and seasons with Celsius temperature ranges, and keep a record of temperature. Students will read the Celsius temperature each day and discuss how given temperatures "feel". They record the temperature by using a string of beads and a chart.

53

Line spectrum and ion temperature measurements from tungsten ions at low ionization stages in large helical device based on vacuum ultraviolet spectroscopy in wavelength range of 500-2200 a)  

NASA Astrophysics Data System (ADS)

Vacuum ultraviolet spectra of emissions released from tungsten ions at lower ionization stages were measured in the Large Helical Device (LHD) in the wavelength range of 500-2200 using a 3 m normal incidence spectrometer. Tungsten ions were distributed in the LHD plasma by injecting a pellet consisting of a small piece of tungsten metal and polyethylene tube. Many lines having different wavelengths from intrinsic impurity ions were observed just after the tungsten pellet injection. Doppler broadening of a tungsten candidate line was successfully measured and the ion temperature was obtained.

Oishi, T.; Morita, S.; Huang, X. L.; Zhang, H. M.; Goto, M.

2014-11-01

54

Line spectrum and ion temperature measurements from tungsten ions at low ionization stages in large helical device based on vacuum ultraviolet spectroscopy in wavelength range of 500-2200 .  

PubMed

Vacuum ultraviolet spectra of emissions released from tungsten ions at lower ionization stages were measured in the Large Helical Device (LHD) in the wavelength range of 500-2200 using a 3 m normal incidence spectrometer. Tungsten ions were distributed in the LHD plasma by injecting a pellet consisting of a small piece of tungsten metal and polyethylene tube. Many lines having different wavelengths from intrinsic impurity ions were observed just after the tungsten pellet injection. Doppler broadening of a tungsten candidate line was successfully measured and the ion temperature was obtained. PMID:25430322

Oishi, T; Morita, S; Huang, X L; Zhang, H M; Goto, M

2014-11-01

55

Design of temperature control device underground coal mine based on AT89S52  

Microsoft Academic Search

Temperature underground coal mine is an important index, especially for mining workers underground. To monitor the temperature effectively, a temperature measurement and control system is necessary to design. Temperature value is displayed on LED screen on line. When temperature value reaches the maximum, conditioning device connected with the opening end of the relay controlled by the MCU will start up.

Qingdong Wang; Jianfeng Wei

2009-01-01

56

Going Places No Infrared Temperature Devices Have Gone Before  

NASA Technical Reports Server (NTRS)

Exergen's IRt/c is a self-powered sensor that matches a thermocouple within specified temperature ranges and provides a predictable and repeatable signal outside of this specified range. Possessing an extremely fast time constant, the infrared technology allows users to measure product temperature without touching the product. The IRt/c uses a device called a thermopile to measure temperature and generate current. Traditionally, these devices are not available in a size that would be compatible with the Exergen IRt/c, based on NASA s quarterinch specifications. After going through five circuit designs to find a thermopile that would suit the IRt/c design and match the signal needed for output, Exergen maintains that it developed a model that totaled just 20 percent of the volume of the previous smallest detector in the world. Following completion of the project with Glenn, Exergen continued development of the IRt/c for other customers, spinning off a new product line called the micro IRt/c. This latest development has broadened applications for industries that previously could not use infrared thermometers due to size constraints. The first commercial use of the micro IRt/c involved an original equipment manufacturer that makes laminating machinery consisting of heated rollers in very tight spots. Accurate temperature measurement for this application requires close proximity to the heated rollers. With the micro IRt/c s 50-millisecond time constant, the manufacturer is able to gain closer access to the intended temperature targets for exact readings, thereby increasing productivity and staying ahead of competition.In a separate application, the infrared temperature sensor is being utilized for avalanche warnings in Switzerland. The IRt/c is mounted about 5 meters above the ground to measure the snow cover throughout the mountainous regions of the country.

2003-01-01

57

An Innovative Flow-Measuring Device: Thermocouple Boundary Layer Rake  

NASA Technical Reports Server (NTRS)

An innovative flow-measuring device, a thermocouple boundary layer rake, was developed. The sensor detects the flow by using a thin-film thermocouple (TC) array to measure the temperature difference across a heater strip. The heater and TC arrays are microfabricated on a constant-thickness quartz strut with low heat conductivity. The device can measure the velocity profile well into the boundary layer, about 65 gm from the surface, which is almost four times closer to the surface than has been possible with the previously used total pressure tube.

Hwang, Danny P.; Fralick, Gustave C.; Martin, Lisa C.; Wrbanek, John D.; Blaha, Charles A.

2001-01-01

58

Constant-Frequency Pulsed Phase-Locked-Loop Measuring Device  

NASA Technical Reports Server (NTRS)

Constant-frequency pulsed phase-locked-loop measuring device is sensitive to small changes in phase velocity and easily automated. Based on use of fixed-frequency oscillator in measuring small changes in ultrasonic phase velocity when sample exposed to such changes in environment as changes in pressure and temperature. Automatically balances electrical phase shifts against acoustical phase shifts to obtain accurate measurements of acoustical phase shifts.

Yost, William T.; Cantrell, John H.; Kushnick, Peter W.

1992-01-01

59

Electromagnetic pulse-induced current measurement device  

NASA Astrophysics Data System (ADS)

To develop safety guidelines for exposure to high fields associated with an electromagnetic pulse (EMP), it is necessary to devise techniques that would measure the peak current induced in the human body. The main focus of this project was to design, fabricate, and test a portable, self-contained stand-on device that would measure and hold the peak current and the integrated change Q. The design specifications of the EMP-Induced Current Measurement Device are as follows: rise time of the current pulse, 5 ns; peak current, 20-600 A; charge Q, 0-20 microcoulombs. The device uses a stand-on parallel-plate bilayer sensor and fast high-frequency circuit that are well-shielded against spurious responses to high incident fields. Since the polarity of the incident peak electric field of the EMP may be either positive or negative, the induced peak current can also be positive or negative. Therefore, the device is designed to respond to either of these polarities and measure and hold both the peak current and the integrated charge which are simultaneously displayed on two separate 3-1/2 digit displays. The prototype device has been preliminarily tested with the EMP's generated at the Air Force Weapons Laboratory (ALECS facility) at Kirtland AFB, New Mexico.

Gandhi, Om P.; Chen, Jin Y.

1991-08-01

60

21 CFR 882.1550 - Nerve conduction velocity measurement device.  

...2014-04-01 false Nerve conduction velocity measurement device. 882.1550... 882.1550 Nerve conduction velocity measurement device. (a) Identification. A nerve conduction velocity measurement device is a...

2014-04-01

61

21 CFR 882.1550 - Nerve conduction velocity measurement device.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 false Nerve conduction velocity measurement device. 882.1550... 882.1550 Nerve conduction velocity measurement device. (a) Identification. A nerve conduction velocity measurement device is a...

2011-04-01

62

21 CFR 882.1550 - Nerve conduction velocity measurement device.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Nerve conduction velocity measurement device. 882.1550... 882.1550 Nerve conduction velocity measurement device. (a) Identification. A nerve conduction velocity measurement device is a...

2012-04-01

63

21 CFR 882.1550 - Nerve conduction velocity measurement device.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Nerve conduction velocity measurement device. 882.1550... 882.1550 Nerve conduction velocity measurement device. (a) Identification. A nerve conduction velocity measurement device is a...

2010-04-01

64

21 CFR 882.1550 - Nerve conduction velocity measurement device.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Nerve conduction velocity measurement device. 882.1550... 882.1550 Nerve conduction velocity measurement device. (a) Identification. A nerve conduction velocity measurement device is a...

2013-04-01

65

21 CFR 864.6400 - Hematocrit measuring device.  

Code of Federal Regulations, 2011 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Manual Hematology Devices 864.6400 Hematocrit measuring device. (a) Identification. A...

2011-04-01

66

21 CFR 864.5950 - Blood volume measuring device.  

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Automated and Semi-Automated Hematology Devices 864.5950 Blood volume measuring device. (a)...

2014-04-01

67

21 CFR 864.6400 - Hematocrit measuring device.  

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Manual Hematology Devices 864.6400 Hematocrit measuring device. (a) Identification. A...

2014-04-01

68

21 CFR 864.6400 - Hematocrit measuring device.  

Code of Federal Regulations, 2012 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Manual Hematology Devices 864.6400 Hematocrit measuring device. (a) Identification. A...

2012-04-01

69

21 CFR 864.5950 - Blood volume measuring device.  

Code of Federal Regulations, 2013 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Automated and Semi-Automated Hematology Devices 864.5950 Blood volume measuring device. (a)...

2013-04-01

70

21 CFR 864.6400 - Hematocrit measuring device.  

Code of Federal Regulations, 2013 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Manual Hematology Devices 864.6400 Hematocrit measuring device. (a) Identification. A...

2013-04-01

71

21 CFR 864.5950 - Blood volume measuring device.  

Code of Federal Regulations, 2010 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Automated and Semi-Automated Hematology Devices 864.5950 Blood volume measuring device. (a)...

2010-04-01

72

21 CFR 864.5950 - Blood volume measuring device.  

Code of Federal Regulations, 2012 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Automated and Semi-Automated Hematology Devices 864.5950 Blood volume measuring device. (a)...

2012-04-01

73

Passive Hybrid MEMS for High-Temperature Telemetric Measurements  

Microsoft Academic Search

A contactless sensor represents an attractive solution for high-temperature measurements in harsh environments, where the use of cables is not suitable, and where the temperature values are beyond those permitted by active electronic circuits. Temperature sensors have a wide variety of applications in automated processes for temperature control and regulation. This paper describes a passive sensing device suitable for high-temperature

Daniele Marioli; Emilio Sardini; Mauro Serpelloni

2010-01-01

74

Weak value measurement with an incoherent measuring device  

E-print Network

In the Aharonov-Albert-Vaidman (AAV) weak measurement, it is assumed that the measuring device or the pointer is in a quantum mechanical pure state. In reality, however, it is often not the case. In this paper, we generalize the AAV weak measurement scheme to include more generalized situations in which the measuring device is in a mixed state. We also report an optical implementation of the weak value measurement in which the incoherent pointer is realized with the pseudo-thermal light. The theoretical and experimental results show that the measuring device under the influence of partial decoherence could still be used for amplified detection of minute physical changes and are applicable for implementing the weak value measurement for massive particles.

Young-Wook Cho; Hyang-Tag Lim; Young-Sik Ra; Yoon-Ho Kim

2009-11-03

75

Measuring ionizing radiation with a mobile device  

NASA Astrophysics Data System (ADS)

In cases of nuclear disasters it is desirable to know one's personal exposure to radioactivity and the related health risk. Usually, Geiger-Mueller tubes are used to assess the situation. Equipping everyone with such a device in a short period of time is very expensive. We propose a method to detect ionizing radiation using the integrated camera of a mobile consumer device, e.g., a cell phone. In emergency cases, millions of existing mobile devices could then be used to monitor the exposure of its owners. In combination with internet access and GPS, measured data can be collected by a central server to get an overview of the situation. During a measurement, the CMOS sensor of a mobile device is shielded from surrounding light by an attachment in front of the lens or an internal shutter. The high-energy radiation produces free electrons on the sensor chip resulting in an image signal. By image analysis by means of the mobile device, signal components due to incident ionizing radiation are separated from the sensor noise. With radioactive sources present significant increases in detected pixels can be seen. Furthermore, the cell phone application can make a preliminary estimate on the collected dose of an individual and the associated health risks.

Michelsburg, Matthias; Fehrenbach, Thomas; Puente Len, Fernando

2012-02-01

76

Air temperature measurement  

NASA Technical Reports Server (NTRS)

A coupled pair of identical film-mounted spherical bead thermistors serve as air temperature sensors aboard both Balloons 8-a and 8-b. The 8-a payload was reeled downward approximately 200 m beneath the balloon. The thermistor mounts were arranged in such a way so that when solar radiation was incident in a direction which was perpendicular to one film, then the direction of the incident solar ray was parallel to the second film. As the payload rotated during the flight (its rotation rate relative to the earth's magnetic field was sensed by a magnetometer), the temperature of each sensor varied depending on the orientation of the film surfaces with respect to the sun.

Ballard, H. N.

1978-01-01

77

Measuring flow experience in gaming devices interactions  

Microsoft Academic Search

This paper describes the work in measuring flow experience while interacting with multi-platform gaming devices. The objective of the study is to identify and measure the variation of flow experience in different platforms. The early pilot data are collected through a survey form that are designed based on gameFlow criteria. The gameFlow criteria consist of eight elements which are: concentration,

Azmi Omar; Nazlena Mohamad Ali; Hairuliza Mohd Judi

2011-01-01

78

Organic light emitting devices with enhanced operational stability at elevated temperatures  

NASA Astrophysics Data System (ADS)

Temperature dependence of electroluminescence degradation is studied in organic light emitting devices containing an emitting layer composed of a mixture of N,N')-di(naphthalene-1-yl-N,N'-diphenyl-benzidine and tris(8-hydroxyquinoline)aluminum (AlQ3), doped with quinacridone green emitter. The emitting layer is sandwiched between hole and electron transport layers. Electroluminescence degradation in time is measured on devices operated at temperatures ranging from 22 to 100 degC. The devices demonstrated remarkable stability, even at elevated temperatures. From accelerated degradation tests, a device half-life of about 78 500, 18 700, and 8600 h can be projected for devices operated at 22, 70, and 100 degC, respectively, at an initial device luminance of 100 cd/m2. Activation energy for device degradation of 0.27 eV is consistent with the recently proposed degradation mechanism based on the unstable cationic AlQ3 species.

Aziz, Hany; Popovic, Zoran D.; Hu, Nan-Xing

2002-07-01

79

Temperature Measurements in the Magnetic Measurement Facility  

SciTech Connect

Several key LCLS undulator parameter values depend strongly on temperature primarily because of the permanent magnet material the undulators are constructed with. The undulators will be tuned to have specific parameter values in the Magnetic Measurement Facility (MMF). Consequently, it is necessary for the temperature of the MMF to remain fairly constant. Requirements on undulator temperature have been established. When in use, the undulator temperature will be in the range 20.0 {+-} 0.2 C. In the MMF, the undulator tuning will be done at 20.0 {+-} 0.1 C. For special studies, the MMF temperature set point can be changed to a value between 18 C and 23 C with stability of {+-}0.1 C. In order to ensure that the MMF temperature requirements are met, the MMF must have a system to measure temperatures. The accuracy of the MMF temperature measurement system must be better than the {+-}0.1 C undulator tuning temperature tolerance, and is taken to be {+-}0.01 C. The temperature measurement system for the MMF is under construction. It is similar to a prototype system we built two years ago in the Sector 10 alignment lab at SLAC. At that time, our goal was to measure the lab temperature to {+-}0.1 C. The system has worked well for two years and has maintained its accuracy. For the MMF system, we propose better sensors and a more extensive calibration program to achieve the factor of 10 increase in accuracy. In this note we describe the measurement system under construction. We motivate our choice of system components and give an overview of the system. Most of the software for the system has been written and will be discussed. We discuss error sources in temperature measurements and show how these errors have been dealt with. The calibration system is described in detail. All the LCLS undulators must be tuned in the Magnetic Measurement Facility at the same temperature to within {+-}0.1 C. In order to ensure this, we are building a system to measure the temperature of the undulators to {+-}0.01 C. This note describes the temperature measurement system under construction.

Wolf, Zachary

2010-12-13

80

High-Sensitivity Temperature Measurement  

ERIC Educational Resources Information Center

Describes a method of measuring small temperature differences that amount to a .01K, using an arrangement of a copper-constantan thermocouple, a microamplifier and a galvanometer, as an indirect way of measuring heat energy. (GA)

Leadstone, G. S.

1978-01-01

81

Air temperature and differential temperature measurement using IC temperature sensors  

Microsoft Academic Search

The Portable Automated Mesonet (PAM) was developed for use as an automatic meteorological measurement system that collects data from an area up to 160 km in diameter by using a surface array of remote sampling stations. The desire arose in this connection to conduct also temperature profile measurements (differential temperature) for use in determining vertical heat flux in turbulent boundary

H. L. Cole

1978-01-01

82

Enhanced Magnetostrictively Transduced SAW Devices - Measurements & Applications  

NASA Astrophysics Data System (ADS)

Surface acoustic wave (SAW) transducers can be made with magnetic materials using magnetostriction as a means of electromechanical coupling. Unlike conventional piezoelectrically transduced SAW devices, the magnetically transduced SAWs do not require an exotic single-crystal substrate or high temperature processing, and therefore may be easily integrated into Si-based integrated circuits. These devices have many potential applications, biosensors being one of the most promising. When the substrate between a transmitter and a detector transducer is functionalized with specific bio-receptors, a binding event will affect propagation of the SAW wave that can be detected with simple electronics. In previous MTSAW devices, the magnetomechanical coupling was found to be poor, resulting in insufficient signal amplitude. To obtain better performance, we are studying the use of alternative magnetostrictive materials including an amorphous CoFeTaZr alloy, CoNbZr, and compositions in the Terfernol family (TbFe2, etc.). We are using combinatorial materials science (continuous composition spread approach) to identify optimum alloy compositions. The devices are also being redesigned to yield better performance.

Woo, Noble C.

2005-03-01

83

Noncontact true temperature measurement, 2  

NASA Technical Reports Server (NTRS)

A laser pyrometer was developed for acquiring the true temperature of a levitated sample. The reflectivity is measured by first expanding the laser beam to cover the entire cross-sectional surface of the diffuse target. The reflectivity calibration of this system is determined from the surface emissivity of a target with a blackbody cavity. The emissivity of the real target can then be calculated. The overall system constant is obtained by passively measuring the radiance of the blackbody cavity (emissivity = 1.0) at a known, arbitrary temperature. Since the photosensor used is highly linear over the entire operating temperature range, the true temperature of the target can then be computed. The latest results available from this on-going research indicate that true temperatures thus obtained are in very good quantitative agreement with thermocouple measured temperatures.

Lee, Mark C.; Allen, James L.

1988-01-01

84

Thermal expansion of blood vessels in low cryogenic temperatures Part I: A new experimental device q  

E-print Network

Thermal expansion of blood vessels in low cryogenic temperatures Part I: A new experimental device of biological material during cryopreservation processes, the current study focuses on thermal expansion device for thermal expansion measurements of blood vessels in typical conditions of vitrifi- cation

Rabin, Yoed

85

Temperature dependence of InAs/GaAs quantum dots solar photovoltaic devices  

NASA Astrophysics Data System (ADS)

This paper presents the temperature dependence measurements characterisation of several InAs/GaAs quantum dots (QDs) solar cell devices. The devices with cylindrical geometry were fabricated and characterised on-wafer under 20 suns in a temperature range from 300K to 430K. The temperature dependence parameters such as open circuit voltage, short circuit density current, fill factor and efficiency are studied in detail. The increase of temperature produces an enhancement of the short circuit current. However, the open circuit voltage is degraded because the temperature increases the recombination phenomena involved, as well as reducing the effective band gap of the semiconductor.

Garduno-Nolasco, E.; Missous, M.; Donoval, D.; Kovac, J.; Mikolasek, M.

2014-05-01

86

Amorphous metallizations for high-temperature semiconductor device applications  

NASA Technical Reports Server (NTRS)

The initial results of work on a class of semiconductor metallizations which appear to hold promise as primary metallizations and diffusion barriers for high temperature device applications are presented. These metallizations consist of sputter-deposited films of high T sub g amorphous-metal alloys which (primarily because of the absence of grain boundaries) exhibit exceptionally good corrosion-resistance and low diffusion coefficients. Amorphous films of the alloys Ni-Nb, Ni-Mo, W-Si, and Mo-Si were deposited on Si, GaAs, GaP, and various insulating substrates. The films adhere extremely well to the substrates and remain amorphous during thermal cycling to at least 500 C. Rutherford backscattering and Auger electron spectroscopy measurements indicate atomic diffussivities in the 10 to the -19th power sq cm/S range at 450 C.

Wiley, J. D.; Perepezko, J. H.; Nordman, J. E.; Kang-Jin, G.

1981-01-01

87

Validity of Devices That Assess Body Temperature During Outdoor Exercise in the Heat  

PubMed Central

Context: Rectal temperature is recommended by the National Athletic Trainers' Association as the criterion standard for recognizing exertional heat stroke, but other body sites commonly are used to measure temperature. Few authors have assessed the validity of the thermometers that measure body temperature at these sites in athletic settings. Objective: To assess the validity of commonly used temperature devices at various body sites during outdoor exercise in the heat. Design: Observational field study. Setting: Outdoor athletic facilities. Patients or Other Participants: Fifteen men and 10 women (age = 26.5 5.3 years, height = 174.3 11.1 cm, mass = 72.73 15.95 kg, body fat = 16.2 5.5%). Intervention(s): We simultaneously tested inexpensive and expensive devices orally and in the axillary region, along with measures of aural, gastrointestinal, forehead, temporal, and rectal temperatures. Temporal temperature was measured according to the instruction manual and a modified method observed in medical tents at local road races. We also measured forehead temperatures directly on the athletic field (other measures occurred in a covered pavilion) where solar radiation was greater. Rectal temperature was the criterion standard used to assess the validity of all other devices. Subjects' temperatures were measured before exercise, every 60 minutes during 180 minutes of exercise, and every 20 minutes for 60 minutes of postexercise recovery. Temperature devices were considered invalid if the mean bias (average difference between rectal temperature and device temperature) was greater than 0.27C (0.5F). Main Outcome Measure(s): Temperature from each device at each site and time point. Results: Mean bias for the following temperatures was greater than the allowed limit of 0.27C (0.5F): temperature obtained via expensive oral device (?1.20C [?2.17F]), inexpensive oral device (?1.67C [?3.00F]), expensive axillary device (?2.58C [?4.65F]), inexpensive axillary device (?2.07C [?3.73F]), aural method (?1.00C [?1.80F]), temporal method according to instruction manual (?1.46C [?2.64F]), modified temporal method (?1.36C [?2.44F]), and forehead temperature on the athletic field (0.60C [1.08F]). Mean bias for gastrointestinal temperature (?0.19C [?0.34F]) and forehead temperature in the pavillion (?0.14C [?0.25F]) was less than the allowed limit of 0.27C (0.5F). Forehead temperature depended on the setting in which it was measured and showed greater variation than other temperatures. Conclusions: Compared with rectal temperature (the criterion standard), gastrointestinal temperature was the only measurement that accurately assessed core body temperature. Oral, axillary, aural, temporal, and field forehead temperatures were significantly different from rectal temperature and, therefore, are considered invalid for assessing hyperthermia in individuals exercising outdoors in the heat. PMID:18059987

Casa, Douglas J; Becker, Shannon M; Ganio, Matthew S; Brown, Christopher M; Yeargin, Susan W; Roti, Melissa W; Siegler, Jason; Blowers, Julie A; Glaviano, Neal R; Huggins, Robert A; Armstrong, Lawrence E; Maresh, Carl M

2007-01-01

88

An unheated permeation device for calibrating atmospheric VOC measurements  

NASA Astrophysics Data System (ADS)

The development of an unpowered permeation device for continuous calibration of in-situ instruments measuring atmospheric volatile organic compounds (VOCs) is described. Being lightweight and compact, and containing only negligible amounts of chemicals, the device is especially suited for field use such as on board aircraft. Its speciality is to maintain the permeation process in thermal equilibrium, so that the instantaneous permeation rate can be ascribed to a simple temperature measurement. This equilibrium state is maintained by a combination of three features: (i) a thin PTFE membrane as permeation medium which guarantees short stabilization times, (ii) a water bath as heat buffer, and (iii) a vacuum-panel based insulation, in which features (ii) and (iii) minimize temperature drifts to ~30 mK h-1 per Kelvin temperature difference to the environment. The respective uncertainty of the permeation rate due to thermal non-equilibrium is kept below 1%. An extensive theory part details the major permeation processes of gases through porous polymers, being Fick's diffusion, Knudsen flow, and viscous flow. Both the measured stabilization time and the measured temperature dependence of the permeation rate independently indicate that the permeation can be described by a viscous flow model, where diffusion of the gas molecules in large pores (having a diameter of >0.05 ?m) dominates.

Brito, J.; Zahn, A.

2011-10-01

89

Containerless high temperature property measurements  

NASA Technical Reports Server (NTRS)

Containerless processing in the low gravity environment of space provides the opportunity to increase the temperature at which well controlled processing of and property measurements on materials is possible. This project was directed towards advancing containerless processing and property measurement techniques for application to materials research at high temperatures in space. Containerless high temperature material property studies include measurements of the vapor pressure, melting temperature, optical properties, and spectral emissivities of solid boron. The reaction of boron with nitrogen was also studied by laser polarimetric measurement of boron nitride film growth. The optical properties and spectral emissivities were measured for solid and liquid silicon, niobium, and zirconium; liquid aluminum and titanium; and liquid Ti-Al alloys of 5 to 60 atomic pct. titanium. Alternative means for noncontact temperature measurement in the absence of material emissivity data were evaluated. Also, the application of laser induced fluorescence for component activity measurements in electromagnetic levitated liquids was studied, along with the feasibility of a hybrid aerodynamic electromagnetic levitation technique.

Nordine, Paul C.; Weber, J. K. Richard; Krishnan, Shankar; Anderson, Collin D.

1991-01-01

90

Devices for flow measurement and control -- 1993  

SciTech Connect

This conference focuses on a small aspect of technological progress, specifically on the devices for flow measurement and control. Papers have been contributed from industry, academia, and government, providing a very broad view of the state of the art and needs for improvement of research. The number of international contributions at this symposium is particularly gratifying to the organizers. There are authors from Great Britain, France, Norway, Germany, and Korea as well as from the US. This implies that flow measurement and control is a topic of significant interest to the international community. It is the editors hope that this symposium volume will serve as a reference for future exchange of ideas and as a catalyst for furthering the state of the art of flow measurement and control. Papers have been processed separately for inclusion on the data base.

Blechinger, C.J. (ed.) (Ford Motor Co., Dearborn, MI (United States)); Sherif, S.A. (ed.) (Univ. of Florida, Gainesville, FL (United States))

1993-01-01

91

Colloidal-gold electrosensor measuring device  

DOEpatents

The present invention provides a new device for use in measuring lead levels in biological and environmental samples. Using square wave coulometry and colloidal gold particles impregnated on carbon electrodes, the present invention provides a rapid, reliable, portable and inexpensive means of detecting low lead levels. The colloidal gold modified electrodes have microelectrode array characteristics and produce significantly higher stripping detection signals for lead than are produced at bulk gold electrode surfaces. The method is effective in determining levels of lead down to at least 5 .mu.g/dL in blood samples as small as 10 .mu.L.

Wegner, Steven (Chapel Hill, NC); Harpold, Michael A. (Durham, NC); McCaffrey, Terence M. (Durham, NC); Morris, Susan E. (Chapel Hill, NC); Wojciechowski, Marek (Cary, NC); Zhao, Junguo (Chapel Hill, NC); Henkens, Robert W. (Durham, NC); Naser, Najih (Durham, NC); O'Daly, John P. (Carrboro, NC)

1995-01-01

92

Switching device for the superconducting phase transition measurements of thin W films using a single superconducting quantum interference device  

Microsoft Academic Search

A simple superconducting switch has been developed for the measurements of the low temperature superconducting phase transitions of several thin W samples connected simultaneously to a single superconducting quantum interference device. The switch, based on a Ti thin film resistor, can be set to normal or to superconducting within the cryostat by adjusting its temperature above or below the transition

G. Sfrn; M. Loidl; O. Meier; G. Angloher; F. Prbst; W. Seidel

1999-01-01

93

Measurement-device-independent quantum cryptography  

E-print Network

In theory, quantum key distribution (QKD) provides information-theoretic security based on the laws of physics. Owing to the imperfections of real-life implementations, however, there is a big gap between the theory and practice of QKD, which has been recently exploited by several quantum hacking activities. To fill this gap, a novel approach, called measurement-device-independent QKD (mdiQKD), has been proposed. It can remove all side-channels from the measurement unit, arguably the most vulnerable part in QKD systems, thus offering a clear avenue towards secure QKD realisations. Here, we review the latest developments in the framework of mdiQKD, together with its assumptions, strengths and weaknesses.

Feihu Xu; Marcos Curty; Bing Qi; Hoi-Kwong Lo

2014-09-17

94

High-Temperature Probe Station Developed to Characterize Microwave Devices Through 500 C  

NASA Technical Reports Server (NTRS)

A photograph and a block diagram of the high-temperature probe station are shown. The system consists of the ceramic heater mounted on a NASA shuttle tile insulator, a direct current power supply, a personal-computer-based data acquisition and temperature controller, microwave probes, a microscope, and a network analyzer. The ability to perform microwave tests at high temperatures is becoming necessary. There is now a need for sensors and communication circuits that can operate at 500 C and above for aircraft engine development and monitoring during flight. To address this need, researchers have fabricated devices using wide bandgap semiconductors such as SiC with targeted operating temperatures of 500 to 600 C. However, the microwave properties of these devices often change drastically with temperature, so any designs that are intended to be used in such an environment must be characterized at high temperatures. For some reliability, lifetime, and direct-current testing, the device under test can be packaged and characterized in an oven. However, for RF and microwave measurements, it is usually not possible to establish a calibrated reference plane at the device terminals within a package. In addition, the characteristics of the package would vary over a 500 C temperature range, and this would have to be accounted for when the data were analyzed. A high temperature probe station allows circuits and devices to be characterized through on wafer measurements across a broad temperature range with known reference plane. The conventional, commercially available thermal wafer-probe stations that are used to evaluate microwave devices across a controlled temperature range have a typical upper limit of 200 C. Standalone thermal heating chucks are available with an extended upper temperature range of 300 to 400 C. To effectively characterize devices at temperatures up to and surpassing 500 C, Glenn researchers developed a custom probe station. In the past, custom probe stations have been developed to test devices under other extreme environments, such as cryogenic temperatures as low as 37 K. Similarly, this custom probe station was specifically modified for high-temperature use. It allows devices to be measured quickly and flexibly, without the use of wire bonds and test fixtures. The probe station is shown making scattering parameter measurements from 1 to 50 GHz with a Hewlett-Packard 8510C Network Analyzer. There is a half-wafer of silicon directly on top of the heater to provide a uniform heated platform for our sample. A quarter wafer of silicon carbide forms the substrate for our test circuit of several transmission lines.

Downey, Alan N.; Schwartz, Zachary D.

2004-01-01

95

Verilog-A Device Models for Cryogenic Temperature Operation of Bulk Silicon CMOS Devices  

NASA Technical Reports Server (NTRS)

Verilog-A based cryogenic bulk CMOS (complementary metal oxide semiconductor) compact models are built for state-of-the-art silicon CMOS processes. These models accurately predict device operation at cryogenic temperatures down to 4 K. The models are compatible with commercial circuit simulators. The models extend the standard BSIM4 [Berkeley Short-channel IGFET (insulated-gate field-effect transistor ) Model] type compact models by re-parameterizing existing equations, as well as adding new equations that capture the physics of device operation at cryogenic temperatures. These models will allow circuit designers to create optimized, reliable, and robust circuits operating at cryogenic temperatures.

Akturk, Akin; Potbhare, Siddharth; Goldsman, Neil; Holloway, Michael

2012-01-01

96

An unheated permeation device for calibrating atmospheric VOC measurements  

NASA Astrophysics Data System (ADS)

The development of an unpowered permeation device for continuous calibration of in-situ instruments measuring atmospheric volatile organic compounds (VOCs) is described. Being lightweight and compact, and containing only negligible amounts of chemicals, the device is especially suited for field use such as onboard aircraft. Its speciality is to maintain the permeation process in thermal equilibrium, i.e. the instantaneous permeation rate can be ascribed via a simple temperature measurement. This equilibrium state is maintained by a combination of three features: (i) a thin PTFE membrane as permeation medium which guarantees short stabilization times, (ii) a water bath as heat buffer, and (iii) a vacuum-panel based insulation, in which features (ii) and (iii) minimize temperature drifts. The uncertainty of the permeation rate due to thermal non-equilibrium is kept below 1 %. An extensive theory part details the major permeation processes of gases through porous polymers, being Fick's diffusion, Knudsen flow, and viscous flow. Both the measured stabilization time and the measured temperature dependence of the permeation rate independently indicate that the permeation can be described by a viscous flow model, where diffusion of the gas molecules in large pores (having a diameter of >0.05 ?m) dominates.

Brito, J.; Zahn, A.

2011-05-01

97

Method for measuring surface temperature  

DOEpatents

The present invention relates to a method for measuring a surface temperature using is a fluorescent temperature sensor or optical thermometer. The sensor includes a solution of 1,3-bis(1-pyrenyl)propane within a 1-butyl-1-1-methyl pyrrolidinium bis(trifluoromethylsulfonyl)imide ionic liquid solvent. The 1,3-bis(1-pyrenyl)propane remains unassociated when in the ground state while in solution. When subjected to UV light, an excited state is produced that exists in equilibrium with an excimer. The position of the equilibrium between the two excited states is temperature dependent.

Baker, Gary A. (Los Alamos, NM); Baker, Sheila N. (Los Alamos, NM); McCleskey, T. Mark (Los Alamos, NM)

2009-07-28

98

Development of silicon carbide semiconductor devices for high temperature applications  

NASA Technical Reports Server (NTRS)

The semiconducting properties of electronic grade silicon carbide crystals, such as wide energy bandgap, make it particularly attractive for high temperature applications. Applications for high temperature electronic devices include instrumentation for engines under development, engine control and condition monitoring systems, and power conditioning and control systems for space platforms and satellites. Discrete prototype SiC devices were fabricated and tested at elevated temperatures. Grown p-n junction diodes demonstrated very good rectification characteristics at 870 K. A depletion-mode metal-oxide-semiconductor field-effect transistor was also successfully fabricated and tested at 770 K. While optimization of SiC fabrication processes remain, it is believed that SiC is an enabling high temperature electronic technology.

Matus, Lawrence G.; Powell, J. Anthony; Petit, Jeremy B.

1991-01-01

99

High temperature thermoreflectance imaging and transient Harman characterization of thermoelectric energy conversion devices  

NASA Astrophysics Data System (ADS)

Advances in thin film growth technology have enabled the selective engineering of material properties to improve the thermoelectric figure of merit and thus the efficiency of energy conversion devices. Precise characterization at the operational temperature of novel thermoelectric materials is crucial to evaluate their performance and optimize their behavior. However, measurements on thin film devices are subject to complications from the growth substrate, non-ideal contacts, and other thermal and electrical parasitic effects. In this manuscript, we determine the cross-plane thermoelectric material properties in a single measurement of a 25 ?m InGaAs thin film with embedded ErAs (0.2%) nanoparticles using the bipolar transient Harman method in conjunction with thermoreflectance thermal imaging at temperatures up to 550 K. This approach eliminates discrepancies and potential device degradation from the multiple measurements necessary to obtain individual material parameters. In addition, we present a strategy for optimizing device geometry to mitigate the effect of both electrical and thermal parasitics during the measurement. Finite element method simulations are utilized to analyze non-uniform current and temperature distributions over the device area as well as the three dimensional current path for accurate extraction of material properties from the thermal images. Results are compared with independent in-plane and 3? measurements of thermoelectric material properties for the same material composition and are found to match reasonably well; the obtained figure of merit matches within 15% at room and elevated temperatures.

Favaloro, T.; Ziabari, A.; Bahk, J.-H.; Burke, P.; Lu, H.; Bowers, J.; Gossard, A.; Bian, Z.; Shakouri, A.

2014-07-01

100

High Temperature Thermoelectric Device Concept Using Large Area PN Junctions  

NASA Astrophysics Data System (ADS)

A new high temperature thermoelectric device concept using large area nanostructured silicon p-type and n-type ( PN) junctions is presented. In contrast to conventional thermoelectric generators, where the n-type and p-type semiconductors are connected electrically in series and thermally in parallel, we experimentally demonstrate a device concept in which a large area PN junction made from highly doped densified silicon nanoparticles is subject to a temperature gradient parallel to the PN interface. In the proposed device concept, the electrical contacts are made at the cold side eliminating the hot side substrate and difficulties that go along with high temperature electrical contacts. This concept allows temperature gradients greater than 300 K to be experimentally applied with hot side temperatures larger than 800 K. Electronic properties of the PN junctions and power output characterizations are presented. A fundamental working principle is discussed using a particle network model with temperature and electric fields as variables, and which considers electrical conductivity and thermal conductivity according to Fourier's law, as well as Peltier and Seebeck effects.

Chavez, R.; Angst, S.; Hall, J.; Stoetzel, J.; Kessler, V.; Bitzer, L.; Maculewicz, F.; Benson, N.; Wiggers, H.; Wolf, D.; Schierning, G.; Schmechel, R.

2014-06-01

101

High Temperature Device Characterization for Hybrid Electric Vehicle Traction Inverters  

Microsoft Academic Search

High temperature inverter involves thermal management, packaging, semiconductor device, switching circuit, and control circuitry. This paper is to focus on the drivetrain inverter design consideration for electric and hybrid electric vehicles. Basic structure and switching characteristics of different insulated-gate-bipolar-transistors (IGBTs) will be discussed. The use of silicon carbide Schottky diode in parallel with silicon IGBT will also be evaluated and

Jih-Sheng Lai; Wensong Yu; Hao Qian; Pengwei Sun; Parish Ralston; Kathleen Meehan

2009-01-01

102

New method of measuring CCD device photoresponse nonuniformity  

NASA Astrophysics Data System (ADS)

A new method of measuring the PRN of CCD device is presented the PRN of CCD device can be determined quickly and accurately by this method, the effect of illuminance distribution nonuniformity on the measurement of CCD device PRN is eliminated.

Wang, Fu; Shen, Xueju; Chen, Weigang; Sun, Xinhua; Dong, Wei; Zhou, Bing

1998-08-01

103

Microfluidic device with integrated temperature control unit for hydrogel actuation  

NASA Astrophysics Data System (ADS)

A microfluidic device, with a temperature control unit to study the behaviour of temperature sensitive hydrogel, has been designed, simulated and fabricated. The system consists of a PDMS (polydimethylsiloxane) microchannel sealed on a Pyrex substrate with microfabricated titanium electrodes for heating and sensing elements. A thermal insulating layer in-between the electrodes and the substrate was found to increase the heat transfer to the fluid and decrease the lateral heat propagation. The temperature profile and the heat distribution in the system were investigated using the commercial software package CFD-ACE+. The device was electrically and thermally characterised. Such a system, biocompatible and re-usable, could be a potential candidate for biomedical applications such as DNA amplification and protein synthesis.

Pachoud, Damien; Mitchell, Arnan; Rosengarten, Gary

2005-02-01

104

Temperature Dependency of MOSFET Device Characteristics in 4H-and 6H-Silicon Carbide (SiC)  

E-print Network

Temperature Dependency of MOSFET Device Characteristics in 4H- and 6H-Silicon Carbide (SiC) Md that includes the effects of temperature variation in 4H- and 6H-SiC poly-type is presented in this paper. SiC results with previously measured experimental data reported in [5]. MOSFET device behavior in 4H-SiC

Tolbert, Leon M.

105

Device and method for measuring the energy content of hot and humid air streams  

Microsoft Academic Search

a portable device and method for measuring enthalpy and humidity of humid air from a space or flow channel at temperatures from 80° to 400° F. is described. the device consists of a psychrometer for measuring wet-bulb temperature, a vacuum pump for inducing sample air flow through the unit, a water-heating system for accurate psychrometer readings, an electronic computer system

H. N. Rosen; G. F. Girod; A. C. Kent

1985-01-01

106

Applications of a high temperature sessile drop device  

NASA Astrophysics Data System (ADS)

The wettability of a liquid metal on a solid surface is of great technological interest for the industry (soldering, brazing, infiltration) as well as for fundamental research (diffusion, chemical reaction, intermetallic phases). The characterization of wetting is done by measuring the contact angle at the triple line of the liquid on the solid. A High Temperature Sessile Drop Device (HTSDD) was constructed and several applications were tested: (i) a wettability study of a copper-based brazing alloy (Cu-ABA) on TiNx coatings with different stoichiometries. The data derived from the HTSDD show that the reduction of the nitrogen content in the TiN coating reduces the time for reaching the final contact angle. Also for substoichiometric TiC a similar behaviour is predicted in literature. (ii) The liquid surface energy of molten metals can be estimated from the curvature of flattened droplets due to the influence of gravity. Two models were used for the calculation of the liquid surface energy of different liquid metals. (iii) From the droplet radius vs. time curves it is possible to distinguish between two different reactive wetting regimes the diffusion and the reaction controlled reactive wetting. The beginning of this research topic will be discussed.

Schwarz, B.; Worbs, P.; Eisenmenger-Sittner, C.

2008-03-01

107

Advanced devices and systems for radiation measurements  

SciTech Connect

The authors` most recent work continues their long-standing efforts to develop semiconductor detectors based on the collection of only a single type of charge carrier. Their best results are an extension of the principle of coplanar electrodes first described by Paul Luke of Lawrence Berkeley Laboratory 18 months ago. This technique, described in past progress reports, has the effect of deriving an output signal from detectors that depends only on the motion of carriers close to one surface. Since nearly all of these carriers are of one type (electrons) that are attracted to that electrode, the net effect is to nearly eliminate the influence of hole motion on the properties of the output signal. The result is that the much better mobility of electrons in compound semiconductors materials such as CZT can now be exploited without the concurrent penalty of poor hole collection. They have also developed new techniques in conjunction with the coplanar electrode principle that extends the technique into a new dimension. By proper processing of signals from the opposite electrode (the cathode) from the coplanar surface, they are able to derive a signal that is a good indication of the depth of interaction at which the charge carriers were initially formed. They have been the first group to demonstrate this technique, and examples of separate pulse height spectra recorded at a variety of different depths of interaction are shown in several of the figures that follow. Obtaining depth information is one step in the direction of obtaining volumetric point-of-interaction information from the detector. If one could known the coordinates of each specific interaction, then corrections could be applied to account for the inhomogeneities that currently plague many room-temperature devices.

Knoll, G.F.; Wehe, D.K.; He, Z.; Barrett, C.; Miyamoto, J.

1996-06-01

108

Laboratory measurements on magnetic water treatment device  

Microsoft Academic Search

A short review of magnetic water treatment (MWT) devices with permanent magnets is given. In the paper, the authors present a model of electromagnetic devices with AC electrical input from 40 to 110 W and radial symmetric water flow from 10 to 400 L\\/min. Electromagnetic properties of the laboratory model EM I are presented and MWT efficiency is discussed. Comparison

Viljeni Kozic; Jurij Krope; Igor Ticar; Edvard Kiker

2001-01-01

109

Infrared Emissivity Measurements of Building and Civil Engineering Materials: A New Device for Measuring Emissivity  

NASA Astrophysics Data System (ADS)

The knowledge of the infrared emissivity of materials used in buildings and civil engineering structures is useful for two specific approaches. First, quantitative diagnosis of buildings or civil engineering infrastructures by infrared thermography requires emissivity values in the spectral bandwidth of the camera used for measurements, in order to obtain accurate surface temperatures; for instance, emissivity in the band III domain is required when using cameras with uncooled detectors (such as micro-bolometer arrays). Second, setting up accurate thermal balances by numerical modeling requires the total emissivity value for a large wavelength domain; this is, for instance, the case for computing the road surface temperature to predict ice occurrence. Furthermore, periodical surveys of emissivity variations due to aging or soiling of surfaces could be useful in many situations such as thermal mapping of roads or building insulation diagnosis. The use of portable emissivity measurement devices is required for that purpose. A device using an indirect measurement method was previously developed in our lab; the method uses measurement of the reflectivity from a modulated IR source and requires calibration with a highly reflective surface. However, that device uses a low-frequency, thermal modulation well adapted to laboratory measurements but unfit for fast and in situ measurements. Therefore, a new, portable system which retains the principle of an indirect measurement but uses a faster-frequency, mechanical modulation more appropriate to outdoor measurements was developed. Both devices allow measurements in the broad m to m) and narrow m to m) bands. Experiments were performed on a large number of materials commonly used in buildings and civil engineering structures. The final objective of this work is to build a database of emissivity of these materials. A comparison of laboratory and on-site measurements of emissivity values obtained in both spectral bands will be presented along with an estimation and an analysis of measurement uncertainties.

Monchau, Jean-Pierre; Marchetti, Mario; Ibos, Laurent; Dumoulin, Jean; Feuillet, Vincent; Candau, Yves

2014-10-01

110

Electrical Devices and Circuits for Low Temperature Space Applications  

NASA Technical Reports Server (NTRS)

The environmental temperature in many NASA missions, such as deep space probes and outer planetary exploration, is significantly below the range for which conventional commercial-off-the-shelf electronics is designed. Presently, spacecraft operating in the cold environment of such deep space missions carry a large number of radioisotope or other heating units in order to maintain the surrounding temperature of the on-board electronics at approximately 20 C. Electronic devices and circuits capable of operation at cryogenic temperatures will not only tolerate the harsh environment of deep space but also will reduce system size and weight by eliminating or reducing the heating units and their associate structures; thereby reducing system development cost as well as launch costs. In addition, power electronic circuits designed for operation at low temperatures are expected to result in more efficient systems than those at room temperature. This improvement results from better behavior in the electrical and thermal properties of some semiconductor and dielectric materials at low temperatures. An on-going research and development program on low temperature electronics at the NASA Glenn Research Center focuses on the development of efficient electrical systems and circuits capable of surviving and exploiting the advantages of low temperature environments. An overview of the program will be presented in this paper. A description of the low temperature test facilities along with selected data obtained from in-house component testing will also be discussed. On-going research activities that are being performed in collaboration with various organizations will also be presented.

Patterson, R. L.; Hammond, A.; Dickman, J. E.; Gerber, S.; Overton, E.; Elbuluk, M.

2003-01-01

111

Ergonomic analysis of slip-resistance measurement devices  

Microsoft Academic Search

Several measurement devices and techniques have been developed during the past 50 years in an attempt to quantify the static and\\/or dynamic coefficient of friction (COF) of shoe and floor surface interfaces. Much of this work has been laboratory research with bulky equipment, but recently portable measurement devices have evolved to the extent that field measurements can be taken. Six

ROBERT O. ANDRES; DON B. CHAFFIN

1985-01-01

112

Bias-temperature instabilities and radiation effects in MOS devices  

Microsoft Academic Search

We report the combined effects of irradiation and bias temperature stress (BTS) on MOS capacitors with HfO2 dielectrics. Irradiation is found to enhance BTS-induced degradation in these devices; significant differences in the amounts of enhancement are observed for different irradiation biases. Zero-bias or positive-bias irradiation followed by negative BTS (NBTS) leads to much worse degradation than either irradiation or NBTS

X. J. Zhou; D. M. Fleetwood; J. A. Felix; E. P. Gusev; C. D'Emic

2005-01-01

113

Temperature effects on the radiation response of MOS devices  

SciTech Connect

The effect of device temperature during irradiation has been investigated for MOS transistors and integrated circuits over the MIL-STD temperature range, -55 to 125/sup 0/C. Large, qualitative changes in transistors and 16k SRAM response are observed both at high and low temperatures. Although changes in transistor response are generally consistent with one'e previous expectations, it is not always straightforward to predict circuit response as a function of temperature. For low dose rate (0.27 rad/s) irradiations of 16k SRAMs, the failure dose at 25/sup 0/C is at least twice that of 125/sup 0/C. This reduction in failure dose, as verified by SPICE simulation, is likely a result of a large increase in SRAM cell imbalance.

Schwank, J.R.; Sexton, F.W.; Fleetwood, D.N.; Jones, R.V.; Flores, R.S.; Rodgers, M.S.; Hughes, K.L.

1988-12-01

114

Thin-film thermoelectric devices with high room-temperature figures of merit  

Microsoft Academic Search

Thermoelectric materials are of interest for applications as heat pumps and power generators. The performance of thermoelectric devices is quantified by a figure of merit, ZT, where Z is a measure of a material's thermoelectric properties and T is the absolute temperature. A material with a figure of merit of around unity was first reported over four decades ago, but

Rama Venkatasubramanian; Edward Siivola; Thomas Colpitts; Brooks O'Quinn

2001-01-01

115

Joseph F. Keithley Award Talk: Microwave Measurements of Mesoscopic Devices  

NASA Astrophysics Data System (ADS)

Typical measurements of mesoscopic devices at low temperatures suffer from annoyingly low speeds and the presence of excess low-frequency noise that can try the experimentalist's patience. Even though these devices are not well-matched to the fifty ohm world of microwaves, the ability to listen to signals coming from a cryogenic nanostructure with a wideband amplifier at gigahertz frequencies has proven quite beneficial. These techniques can be surprising precise and powerful, allowing access to high-speed dynamics, the collection of information from wideband signals such as noise, and an entry into the domain of quantum electrical signals. I will review some of our early experiments at Yale in this area, especially the development of the Radio-Frequency Single-Electron Transistor (RF-SET), which is still the most sensitive electrometer known. Today we find that microwave measurements are proving highly beneficial for solid-state quantum computing, which in turn is leading to a new wave of capabilities for generating and measuring microwave signals at the single photon level.

Schoelkopf, Robert

2009-03-01

116

Measurement of device parameters using image recovery techniques in large-scale IC devices  

Microsoft Academic Search

Devices that respond to radiation on a cell level will produce distributions showing the relative frequency of cell response to radiation damage, i.e., a probability distribution of a cell to be damaged a certain amount. The measured distribution is the convolution of distributions from radiation responses, measurement noise, and manufacturing parameters. A method of extracting device characteristics and parameters from

Leif Scheick; Larry Edmonds

2004-01-01

117

A Simple Flow Measuring Device for Farms  

E-print Network

can be constructed using metal or plywood and a short piece of PVC or metal pipe. When the flume PVC or metal pipe contracting both sides. The cross section of the device is thereby constricted using lengthwise half sections of PVC or metal pipe as shown in fig. 1 (top view). The side view of the flume

118

Temperature and Strain Coefficient of Velocity for Langasite SAW Devices  

NASA Technical Reports Server (NTRS)

Surface Acoustic Wave sensors on Langasite substrates are being investigated for aerospace applications. Characterization of the Langasite material properties must be performed before sensors can be installed in research vehicles. The coefficients of velocity for both strain and temperature have been determined. These values have also been used to perform temperature compensation of the strain measurements.

Wilson, W. C.; Atkinson, G. M.

2013-01-01

119

Device and method for measuring thermal conductivity of thin films  

NASA Technical Reports Server (NTRS)

A device and method are provided for measuring the thermal conductivity of rigid or flexible, homogeneous or heterogeneous, thin films between 50 .mu.m and 150 .mu.m thick with relative standard deviations of less than five percent. The specimen is sandwiched between like material, highly conductive upper and lower slabs. Each slab is instrumented with six thermocouples embedded within the slab and flush with their corresponding surfaces. A heat source heats the lower slab and a heat sink cools the upper slab. The heat sink also provides sufficient contact pressure onto the specimen. Testing is performed within a vacuum environment (bell-jar) between 10.sup.-3 to 10.sup.-6 Torr. An anti-radiant shield on the interior surface of the bell-jar is used to avoid radiation heat losses. Insulation is placed adjacent to the heat source and adjacent to the heat sink to prevent conduction losses. A temperature controlled water circulator circulates water from a constant temperature bath through the heat sink. Fourier's one-dimensional law of heat conduction is the governing equation. Data, including temperatures, are measured with a multi-channel data acquisition system. On-line computer processing is used for thermal conductivity calculations.

Amer, Tahani R. (Inventor); Subramanian, Chelakara (Inventor); Upchurch, Billy T. (Inventor); Alderfer, David W. (Inventor); Sealey, Bradley S. (Inventor); Burkett, Jr., Cecil G. (Inventor)

2001-01-01

120

Graphene, a material for high temperature devices - intrinsic carrier density, carrier drift velocity, and lattice energy  

NASA Astrophysics Data System (ADS)

Heat has always been a killing matter for traditional semiconductor machines. The underlining physical reason is that the intrinsic carrier density of a device made from a traditional semiconductor material increases very fast with a rising temperature. Once reaching a temperature, the density surpasses the chemical doping or gating effect, any p-n junction or transistor made from the semiconductor will fail to function. Here, we measure the intrinsic Fermi level (|EF| = 2.93 kBT) or intrinsic carrier density (nin = 3.87 106 cm-2K-2.T2), carrier drift velocity, and G mode phonon energy of graphene devices and their temperature dependencies up to 2400 K. Our results show intrinsic carrier density of graphene is an order of magnitude less sensitive to temperature than those of Si or Ge, and reveal the great potentials of graphene as a material for high temperature devices. We also observe a linear decline of saturation drift velocity with increasing temperature, and identify the temperature coefficients of the intrinsic G mode phonon energy. Above knowledge is vital in understanding the physical phenomena of graphene under high power or high temperature.

Yin, Yan; Cheng, Zengguang; Wang, Li; Jin, Kuijuan; Wang, Wenzhong

2014-07-01

121

A novel forficiform device for both temperature-compensating package for fiber Bragg gratings and cryogenic fiber Bragg grating temperature sensors  

Microsoft Academic Search

We present a novel forficiform device for both the temperature-compensating package for fiber Bragg gratings(FBGs) and cryogenic FBG temperature sensors. The wavelengths of the reflected light from 1550nm FBGs are measured in the temperature range from 77K to 353K .The temperature sensitivity of FBG sensors can be reduced by more than 10 times, reaching 0.001nm\\/K in the temperature range from

Gang Yu; Dan Cao

2005-01-01

122

Pyrometric Gas and Surface Temperature Measurements.  

National Technical Information Service (NTIS)

A multiwavelength pyrometer possessing advantages over the one- and two-wavelength designs is described. Results of its application to surface temperature measurements of ceramics is presented. Also described is a probe suitable for gas temperature measur...

G. Fralick, D. Ng

1999-01-01

123

Micro-PIT/V --- Simultaneous temperature and velocity fields in microfluidic devices  

NASA Astrophysics Data System (ADS)

The use of encapsulated thermochromic liquid crystals (TLC) for the simultaneous measurement of temperature and velocity fields in microfluidic devices has been demonstrated. Implementation of TLC thermometry at the micro-scale is significantly different than at the macro-scale due to the constraints on imaging and illumination configurations and the proximity of the measurements to interfaces and surfaces from which light will scatter. Unlike in micro-PIV, wavelength filtering (such as with fluorescent particles) cannot be used to remove undesired reflections, because the temperature information is carried by the particle color. Therefore, circular polarization filtering is used, exploiting the circular dichroism of TLC. Micro-PIT/V will enable new investigations into the physics of microfluidic devices involving temperature gradients, such as thermocapillary actuated devices and many ``lab-on-a-chip'' applications involving temperature sensitive chemical and biological processes. In addition, the design of operational devices can be improved by applying micro-PIT/V to the characterization of prototypes.

Pottebaum, Tait

2008-11-01

124

Low Cost Device For Light Flicker Measurement  

Microsoft Academic Search

A new instrument for the evaluation of disturbances caused by variations in lamp voltage (light flicker) is proposed, based on light intensity measurements. Unlike current standard (IEC EN 61000-4-15), which determines flicker severity by filtering powering voltage measurements with a standard lamp model (230V\\/60W), the presented methodology includes the lamp itself in the measurement process, thus realizing an objective measurement

Daniele Gallo; Carmine Landi; Nicola Pasquino

125

121. Man with temperature probe aimed at armature measuring temperature ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

121. Man with temperature probe aimed at armature measuring temperature as armature heats up between the two electrodes. March 27, 1985 - Statue of Liberty, Liberty Island, Manhattan, New York, New York County, NY

126

Insitu Rock Shear Device (Development of a New Insitu Shear Strength Measuring Device).  

National Technical Information Service (NTIS)

A new device has been designed to measure the insitu rock shear strength in cored holes. Limited field data indicate that shear strengths obtained by the Rock Shear Device are in good agreement with McVay's laboratory square root (sup 2) method.

C. Hay, D. Bloomquist, M. McVay

2008-01-01

127

High Density And High Temperature Plasmas In Large Helical Device  

NASA Astrophysics Data System (ADS)

For the realization of the fusion reactor, it is necessary to confine high density and high temperature plasma for a time, which is well known as the Lawson criterion. To improve the plasma or confinement performance, vigorous experiments have been performed in the Large Helical Device (LHD) in National Institute for Fusion Science, which is the largest superconducting heliotron device with R = 3.9 m r = 0.6 m, Bt = 3 T. Recently a promising confinement regime called Super Dense Core (SDC) mode was discovered. An extremely high density core region with more than ~ 1 10^20 m-3 is obtained with the formation of an Internal Diffusion Barrier (IDB). The density gradient at the IDB (? = 0.6) is very high and the particle confinement in the core region is ~ 0.2 s. It is expected, for the future reactor, that the IDB-SDC mode has a possibility to achieve the self-ignition condition with lower temperature than expected before. The IDB-SDC mode is also favorable from the engineering point of view since one can moderate demands for heating devices and plasma facing components. In order to achieve the IDB-SDC mode, the central fuelling with the pellet injection and the low recycling condition are essential. A repetitive pellet injector was newly developed to continuously feed the particle source to the central region. For the recycling control, the effective divertor system should be employed to control the edge plasma. Conventional approaches to increase the temperature have also been tried in LHD. For the ion heating, the perpendicular neutral beam injection effectively increased the ion temperature more than 10 keV with the formation of the internal transport barrier (ITB). In the core region, the heat conductivity is improved to the neoclassical level, while no clear ITB for electron was seen. Another interesting phenomenon called "impurity hole" was observed inside the ITB. During the high ion temperature discharge, the im- purity density in the core region becomes low and its profile becomes hollow. The impurity atoms are pumped out, in spite of the negative electric field (ion root) inside the ITB. In the lecture, the mechanism of the impurity hole will also be discussed, together with the theoretical background and numerical results.

Komori, A.

2010-07-01

128

Gas-Temperature Measurement With Minimal Perturbation  

NASA Technical Reports Server (NTRS)

Method for measuring temperature of hot turbulent gases uses three heatflux calorimeters. One calorimeter measures radiative heat flux, while other two measure total heat flux (convective and radiative), at two different temperatures. Adapted for commercial uses in such operations as monitoring temperatures of flue gases, piped liquid or gaseous products, internal-combustion or jet engine exhausts.

Fu, T. S.; Quan, M.

1983-01-01

129

Nanometer-scale temperature imaging for independent observation of Joule and Peltier effects in phase change memory devices  

NASA Astrophysics Data System (ADS)

This paper reports a technique for independent observation of nanometer-scale Joule heating and thermoelectric effects, using atomic force microscopy (AFM) based measurements of nanometer-scale temperature fields. When electrical current flows through nanoscale devices and contacts the temperature distribution is governed by both Joule and thermoelectric effects. When the device is driven by an electrical current that is both periodic and bipolar, the temperature rise due to the Joule effect is at a different harmonic than the temperature rise due to the Peltier effect. An AFM tip scanning over the device can simultaneously measure all of the relevant harmonic responses, such that the Joule effect and the Peltier effect can be independently measured. Here we demonstrate the efficacy of the technique by measuring Joule and Peltier effects in phase change memory devices. By comparing the observed temperature responses of these working devices, we measure the device thermopower, which is in the range of 30 3 to 250 10 ?V K-1. This technique could facilitate improved measurements of thermoelectric phenomena and properties at the nanometer-scale.

Grosse, Kyle L.; Pop, Eric; King, William P.

2014-09-01

130

Nanometer-scale temperature imaging for independent observation of Joule and Peltier effects in phase change memory devices.  

PubMed

This paper reports a technique for independent observation of nanometer-scale Joule heating and thermoelectric effects, using atomic force microscopy (AFM) based measurements of nanometer-scale temperature fields. When electrical current flows through nanoscale devices and contacts the temperature distribution is governed by both Joule and thermoelectric effects. When the device is driven by an electrical current that is both periodic and bipolar, the temperature rise due to the Joule effect is at a different harmonic than the temperature rise due to the Peltier effect. An AFM tip scanning over the device can simultaneously measure all of the relevant harmonic responses, such that the Joule effect and the Peltier effect can be independently measured. Here we demonstrate the efficacy of the technique by measuring Joule and Peltier effects in phase change memory devices. By comparing the observed temperature responses of these working devices, we measure the device thermopower, which is in the range of 30 3 to 250 10 ?V K(-1). This technique could facilitate improved measurements of thermoelectric phenomena and properties at the nanometer-scale. PMID:25273761

Grosse, Kyle L; Pop, Eric; King, William P

2014-09-01

131

Measuring Specific Heats at High Temperatures  

NASA Technical Reports Server (NTRS)

Flash apparatus for measuring thermal diffusivities at temperatures from 300 to 1,000 degrees C modified; measures specific heats of samples to accuracy of 4 to 5 percent. Specific heat and thermal diffusivity of sample measured. Xenon flash emits pulse of radiation, absorbed by sputtered graphite coating on sample. Sample temperature measured with thermocouple, and temperature rise due to pulse measured by InSb detector.

Vandersande, Jan W.; Zoltan, Andrew; Wood, Charles

1987-01-01

132

Manufacturers of light sensitive devices need to measure the  

E-print Network

characteristics. Prior state of art typically consists of a light distribution device, having at least one input portion to receive the reflected light beam in a known ratio to two areas, where a photovoltaic device the spectra using optical filters. The result of this unique combination of characteristics is that measuring

Langendoen, Koen

133

Apparatus Would Measure Temperatures Of Ball Bearings  

NASA Technical Reports Server (NTRS)

Rig for testing ball bearings under radial and axial loads and measuring surface temperatures undergoing development. Includes extensible thermocouples: by means of bellows as longitudinal positioners, thermocouples driven into contact with bearing balls to sense temperatures immediately after test run. Not necessary to disassemble rig or to section balls to obtain indirect indications of maximum temperatures reached. Thermocouple measurements indicate temperatures better than temperature-sensitive paints.

Gibson, John C.; Fredricks, Thomas H.

1995-01-01

134

An all optical method for lab-on-a-chip temperature measurements  

NASA Astrophysics Data System (ADS)

We demonstrate the use of Spatially and Spectrally Resolved Interferometry (SSRI) to measure minute temperature changes in picoliter volumes. The SSRI technique allows the measurement of refractive index changes as a function of temperature, frequency, and one spatial dimension within a microfluidic device. Integration of optical fibers and inexpensive light sources facilitate the progress of this method toward ``lab on a chip'' applications. Additionally, careful construction of microfluidic devices, in combination with SSRI will enable in-situ control of thermal gradients across the channel. Broad applications of this technology could include the measurements of reaction enthalpies, development of accurate temperature measurements in microfluidic devices, and precise characterization of temperature gradients.

Goering, Adam; Adams, Dan; Squier, Jeff; Durfee, Charles; Williams, Kim

2009-10-01

135

29. HAWSER DEVICE, DEVELOPED AT WES FOR MEASURING LONGITUDINAL AND ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

29. HAWSER DEVICE, DEVELOPED AT WES FOR MEASURING LONGITUDINAL AND TRANSVERSE STRESS OF BARGES IN CANAL LOCKS. - Waterways Experiment Station, Hydraulics Laboratory, Halls Ferry Road, 2 miles south of I-20, Vicksburg, Warren County, MS

136

33. BENTZEL TUBE. A CURRENT VELOCITY MEASURING DEVICE DEVELOPED AT ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

33. BENTZEL TUBE. A CURRENT VELOCITY MEASURING DEVICE DEVELOPED AT WES IN 1932 BY CARL E. BENTZEL. - Waterways Experiment Station, Hydraulics Laboratory, Halls Ferry Road, 2 miles south of I-20, Vicksburg, Warren County, MS

137

Experimental Semi-Device-Independent Certification of Entangled Measurements  

NASA Astrophysics Data System (ADS)

Certifying the entanglement of quantum states with Bell inequalities allows one to guarantee the security of quantum information protocols independently of imperfections in the measuring devices. Here, we present a similar procedure for witnessing entangled measurements, which play a central role in many quantum information tasks. Our procedure is termed semi-device-independent, as it uses uncharacterized quantum preparations of fixed Hilbert space dimension. Using a photonic setup, we experimentally certify an entangled measurement using only measurement statistics. We also apply our techniques to certify unentangled but nevertheless inherently quantum measurements.

Bennet, Adam; Vrtesi, Tams; Saunders, Dylan J.; Brunner, Nicolas; Pryde, G. J.

2014-08-01

138

Measurement of small temperature fluctuations at high average temperature  

NASA Technical Reports Server (NTRS)

Both absolute and differential temperature measurements were simultaneously performed as a function of time for a pixel on a high-temperature, multi-spectral, spatially and temporally varying infrared target simulator. A scanning laser beam was used to maintain a pixel at an on-the-average constant temperature of 520 K. The laser refresh rate of up to 1 kHz resulted in small-amplitude temperature fluctuations with a peak-to-peak amplitude of less than 1 K. The experimental setup to accurately measure the differential and the absolute temperature as a function of time is described.

Scholl, James W.; Scholl, Marija S.

1988-01-01

139

Measurement of thermodynamic temperature of high temperature fixed points  

SciTech Connect

The paper is devoted to VNIIOFI's measurements of thermodynamic temperature of the high temperature fixed points Co-C, Pt-C and Re-C within the scope of the international project coordinated by the Consultative Committee for Thermometry working group 5 'Radiation Thermometry'. The melting temperatures of the fixed points were measured by a radiance mode radiation thermometer calibrated against a filter radiometer with known irradiance spectral responsivity via a high temperature black body. This paper describes the facility used for the measurements, the results and estimated uncertainties.

Gavrilov, V. R.; Khlevnoy, B. B.; Otryaskin, D. A.; Grigorieva, I. A.; Samoylov, M. L.; Sapritsky, V. I. [All-Russian Research Institute for Optical and Physical Measurements (VNIIOFI), 46 Ozernaya St., Moscow 119361 (Russian Federation)] [All-Russian Research Institute for Optical and Physical Measurements (VNIIOFI), 46 Ozernaya St., Moscow 119361 (Russian Federation)

2013-09-11

140

Temperature Measurements of Flames containing Incandescent Particles  

Microsoft Academic Search

Colour temperatures measured on photoflash powders are higher than expected from theoretical calculations Determinations of the true temperature of stationary flames of aluminium flakes suspended in air have been made (a) by a line reversal method and (b) by measuring the absolute light intensity. The experimental values obtained were very close to the theoretical flame temperature of about 3,000 C.,

H G Wolfhard; W G Parker

1949-01-01

141

Software for keratometry measurements using portable devices  

Microsoft Academic Search

In this work we present an image processing software for automatic astigmatism measurements developed for a hand held keratometer. The system projects 36 light spots, from LEDs, displayed in a precise circle at the lachrymal film of the examined cornea. The displacement, the size and deformation of the reflected image of these light spots are analyzed providing the keratometry. The

C. M. Iyomasa; L. Ventura; J. J. de Groote

2010-01-01

142

Quantum throughput: Quantifying quantum-communication devices with homodyne measurements  

SciTech Connect

Quantum communication relies on optical implementations of channels, memories, and repeaters. In the absence of perfect devices, a minimum requirement on real-world devices is that they preserve quantum correlations, meaning that they have some throughput of a quantum-mechanical nature. Previous work has verified throughput in optical devices while using minimal resources. We extend this approach to the quantitative regime. Our method is illustrated in a setting where the input consists of two coherent states while the output is measured by two homodyne measurement settings.

Killoran, N. [Institute for Quantum Computing and Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada); Haeseler, H.; Luetkenhaus, N. [Institute for Quantum Computing and Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada); Max Planck Institute for the Physics of Light, Universitaet Erlangen-Nuernberg, 91058 Erlangen (Germany)

2010-11-15

143

High-frequency noise measurements in spin-valve devices  

NASA Astrophysics Data System (ADS)

High-frequency magnetic noise in magnetoresistive devices being developed for read-sensor and magnetic random access memory applications may present fundamental limitations on the performance of submicrometer magnetic devices. High-frequency magnetic noise (HFN) arises from intrinsic thermal fluctuations of the device magnetization. High-frequency noise spectroscopy provides a powerful tool to characterize the dynamics and response of small multilayer magnetic devices. In this study, the noise characteristics of micrometer-dimension spin valves have been investigated at frequencies in the range 0.1-6 GHz. At frequencies below this range 1/f noise dominates. HFN measurements, as a function of bias current and longitudinal magnetic field, are obtained for IrMn exchange-biased spin valves using a 50 GHz spectrum analyzer, low-noise amplifier, and a microwave probing system. The magnetic noise is obtained by taking the difference between the noise spectrum of the device in a saturated and unsaturated state. The data can be fit to simple models that predict the noise power to be proportional to the imaginary part of the free-layer magnetic susceptibility. There are some important differences between the high-frequency noise measurements and direct measurements of the device susceptibility (both at the device and wafer level). The noise measurements show a smaller damping parameter (a smaller ferromagnetic resonance linewidth) and additional features due to the presence of nonuniform modes.

Stutzke, N. A.; Burkett, S. L.; Russek, S. E.

2003-07-01

144

Low-cost optoelectronic devices to measure velocity of detonation  

NASA Astrophysics Data System (ADS)

Velocity of Detonation (VoD) is an important measured characteristic parameter of explosive materials. When new explosives are developed, their VoD must be determined. Devices used to measure VoD are always destroyed in the process, however replacing these devices represents a considerable cost in the characterisation of new explosives. This paper reports the design and performance of three low-cost implementations of a point-to-point VoD measurement system, two using optical fibre and a third using piezoelectric polymers (PolyVinyliDine Flouride, PVDF). The devices were designed for short charges used under controlled laboratory conditions and were tested using the common explosive 'Composition B'. These new devices are a fraction of the cost of currently available VoD sensors and show promise in achieving comparable accuracy. Their future development will dramatically reduce the cost of testing and aid the characterisation of new explosives.

Chan, Edwin M.; Lee, Vivian; Mickan, Samuel P.; Davies, Phil J.

2005-02-01

145

Spectroscopic Temperature Measurements in Interior Ballistic Environments.  

National Technical Information Service (NTIS)

Spectroscopic temperature measurements during the interior ballistic cycle of a 20 mm test fixture gun and inside the muzzle flash of a 7.62 mm rifle are described. The investigation yields information on temperature distribution in the burning propellant...

G. Klingenberg, H. Mach

1984-01-01

146

Microparticles temperature measurements in a plasma jet  

Microsoft Academic Search

A high spatial resolution spectroscopic technique was developed for temperature measurements of micro-particles heated in a plasma jet. The knowledge of the particles temperature distribution was used to optimize the plasma spraying process.

D Oliver; R Enikov

2000-01-01

147

Finger temperature controller for non-invasive blood glucose measurement  

NASA Astrophysics Data System (ADS)

Blood glucose level is an important parameter for doctors to diagnose and treat diabetes. The Near-Infra-Red (NIR) spectroscopy method is the most promising approach and this involves measurement on the body skin. However it is noted that the skin temperature does fluctuate with the environmental and physiological conditions and we found that temperature has important influences on the glucose measurement. In-vitro and in-vivo investigations on the temperature influence on blood glucose measurement have been carried out. The in-vitro results show that water temperature has significant influence on water absorption. Since 90% of blood components are water, skin temperature of measurement site has significant influence on blood glucose measurement. Also the skin temperature is related to the blood volume, blood volume inside capillary vessels changes with skin temperature. In this paper the relationship of skin temperature and signal from the skin and inside tissue was studied at different finger temperatures. Our OGTT (oral glucose tolerance test) trials results show the laser signals follow the skin temperature trend and the correlation of signal and skin temperature is much stronger than the correlation of signal and glucose concentration. A finger heater device is designed to heat and maintain the skin temperature of measurement site. The heater is controlled by an electronic circuit according to the skin temperature sensed by a thermocouple that is put close to the measurement site. In vivo trials were carried out and the results show that the skin temperature significantly influences the signal fluctuations caused by pulsate blood and the average signal value.

Zhang, Xiqin; Ting, Choon Meng; Yeo, Joon Hock

2010-11-01

148

Emitted vibration measurement device and method  

NASA Technical Reports Server (NTRS)

This invention is directed to a method and apparatus for measuring emitted vibrational forces produced by a reaction wheel assembly due to imbalances, misalignment, bearing defects and the like. The apparatus includes a low mass carriage supported on a large mass base. The carriage is in the form of an octagonal frame having an opening which is adapted for receiving the reaction wheel assembly supported thereon by means of a mounting ring. The carriage is supported on the base by means of air bearings which support the carriage in a generally frictionless manner when supplied with compressed air from a source. A plurality of carriage brackets and a plurality of base blocks provided for physical coupling of the base and carriage. The sensing axes of the load cells are arranged generally parallel to the base and connected between the base and carriage such that all of the vibrational forces emitted by the reaction wheel assembly are effectively transmitted through the sensing axes of the load cells. In this manner, a highly reliable and accurate measurment of the vibrational forces of the reaction wheel assembly can be had. The output signals from the load cells are subjected to a dynamical analyzer which analyzes and identifies the rotor and spin bearing components which are causing the vibrational forces.

Gisler, G. L. (inventor)

1986-01-01

149

Optical sensing techniques for temperature measurement.  

PubMed

Temperature is an important parameter that needs accurate measurement. Theoretical descriptions of the fluorescence ratio method, fluorescence lifetime sensing, and interferometric methods for temperature measurement are given. Fluorescence lifetime sensing calibration plots have been developed for temperature measurement from 20C to 600C using Er(3+)-doped glass, and from 20C to 90C using Sm(3+)-doped CaF(2). Lifetime sensing results of Pr(3+)-doped YAG and Ho(3+)-doped fluoride crystals for temperature measurement are also summarized. Mach-Zehnder interferometer measurements revealed that the passage of a 300 mW laser beam of 915 nm changed the temperature of the Yb(3+)-doped YAG crystal by 7.1C. The interferometer technique is useful for measuring absolute temperature changes in laser cooling studies. PMID:23385939

Reddy, B Rami; Kamma, Indumathi; Kommidi, Praveena

2013-02-01

150

Effects of chamber pressure variation on the grid temperature in an inertial electrostatic confinement device  

Microsoft Academic Search

Inertial electrostatic confinement fusion devices are compact sources of neutrons, protons, electrons, and x rays. Such sources have many applications. Improving the efficiency of the device also increases the applications of this device. Hence a thorough understanding of the operation of this device is needed. In this paper, we study the effect of chamber pressure on the temperature of the

S. Krupakar Murali; G. A. Emmert; J. F. Santarius; G. L. Kulcinski

2010-01-01

151

Correlation between temperature coefficient of elasticity and fourier transform infrared spectra of silicon dioxide films for surface acoustic wave devices.  

PubMed

We investigated the correlation between the temperature coefficient of elasticity (TCE) and Fourier transform infrared (FT-IR) absorption spectra of SiO(2) for SAW devices. The measurement indicated that the TCE is strongly correlated with peak frequencies; that is, with the fractional change of the Si-O-Si bond angle with temperature. PMID:21859588

Matsuda, Satoru; Hara, Motoaki; Miura, Michio; Matsuda, Takashi; Ueda, Masanori; Satoh, Yoshio; Hashimoto, Ken-Ya

2011-08-01

152

Method and apparatus for optical temperature measurements  

DOEpatents

A method and apparatus are provided for remotely monitoring temperature. Both method and apparatus employ a temperature probe material having an excitation-dependent emission line whose fluorescence intensity varies directly with temperature whenever excited by light having a first wavelength and whose fluorescence intensity varies inversely with temperature whenever excited by light having a second wavelength. Temperature is measured by alternatively illiminating the temperature probe material with light having the first wavelength and light having the second wavelength, monitoring the intensity of the successive emissions of the excitation-dependent emission line, and relating the intensity ratio of successive emissions to temperature. 3 figs.

Angel, S.M.; Hirschfeld, T.B.

1986-04-22

153

Simulated limnological effects of the Shasta Lake temperature control device.  

PubMed

We estimated the effects of a temperature control device (TCD) on a suite of thermodynamic and limnological attributes for a large storage reservoir, Shasta Lake, in northern California. Shasta Dam was constructed in 1945 with a fixed-elevation penstock. The TCD was installed in 1997 to improve downstream temperatures for endangered salmonids by releasing epilimnetic waters in the winter/spring and hypolimnetic waters in the summer/fall. We calibrated a two-dimensional hydrodynamic reservoir water quality model, CE-QUAL-W2, and applied a structured design-of-experiment simulation procedure to predict the principal limnological effects of the TCD under a variety of environmental scenarios. Calibration goodness-of-fit ranged from good to poor depending on the constituent simulated, with an R2 of 0.9 for water temperature but 0.3 for phytoplankton. Although the chemical and thermal characteristics of the discharge changed markedly, the reservoir's characteristics remained relatively unchanged. Simulations showed the TCD causing an earlier onset and shorter duration of summer stratification, but no dramatic affect on Shasta's nutrient composition. Peak inreservoir phytoplankton production may begin earlier and be stronger in the fall with the TCD, while outfall phytoplankton concentrations may be much greater in the spring. Many model predictions differed from our a priori expectations that had been shaped by an intensive, but limited-duration, data collection effort. Hydrologic and meteorological variables, most notably reservoir carryover storage at the beginning of the calendar year, influenced model predictions much more strongly than the TCD. Model results indicate that greater control over reservoir limnology and release quality may be gained by carefully managing reservoir volume through the year than with the TCD alone. PMID:11289458

Bartholow, J; Hanna, R B; Saito, L; Lieberman, D; Horn, M

2001-04-01

154

Thermal measurement and analysis of micro devices using thermography  

Microsoft Academic Search

Sensors and actuators become much smaller as parts of MEMS devices. Some of them run based on the thermal principle and thermal characteristics directly determine their performance. For example, micro-hotplate structures are incorporated into integrated gas sensors to heat the sensing thin film to a determinate temperature with a high sensitivity. The micro-machined accelerometer with no proof mass is based

Y. Q. Gu; Ronghai Zhang; Dezhong Zhu

2003-01-01

155

Measurement kernel design for compressive imaging under device constraints  

NASA Astrophysics Data System (ADS)

We look at the design of projective measurements for compressive imaging based upon image priors and device constraints. If one assumes that image patches from natural imagery can be modeled as a low rank manifold, we develop an optimality criterion for a measurement matrix based upon separating the canonical elements of the manifold prior. We then describe a stochastic search algorithm for finding the optimal measurements under device constraints based upon a subspace mismatch algorithm. The algorithm is then tested on a prototype compressive imaging device designed to collect an 8x4 array of projective measurements simultaneously. This work is based upon work supported by DARPA and the SPAWAR System Center Pacific under Contract No. N66001-11-C-4092. The views expressed are those of the author and do not reflect the official policy or position of the Department of Defense or the U.S. Government.

Shilling, Richard; Muise, Robert

2013-05-01

156

Method and apparatus for optical temperature measurement  

DOEpatents

A temperature probe and a method for using said probe for temperature measurements based on changes in light absorption by the probe are disclosed. The probe comprises a first and a second optical fiber that carry light to and from the probe, and a temperature sensor material, the absorbance of which changes with temperature, through which the light is directed. Light is directed through the first optical fiber, passes through the temperature sensor material, and is transmitted by a second optical fiber from the material to a detector. Temperature-dependent and temperature-independent factors are derived from measurements of the transmitted light intensity. For each sensor material, the temperature T is a function of the ratio, R, of these factors. The temperature function f(R) is found by applying standard data analysis techniques to plots of T versus R at a series of known temperatures. For a sensor having a known temperature function f(R) and known characteristic and temperature-dependent factors, the temperature can be computed from a measurement of R. Suitable sensor materials include neodymium-doped borosilicate glass, accurate to [+-]0.5 C over an operating temperature range of about [minus]196 C to 400 C; and a mixture of D[sub 2]O and H[sub 2]O, accurate to [+-]0.1 C over an operating range of about 5 C to 90 C. 13 figs.

O'Rourke, P.E.; Livingston, R.R.; Prather, W.S.

1994-09-20

157

Method and apparatus for optical temperature measurement  

DOEpatents

A temperature probe and a method for using said probe for temperature measurements based on changes in light absorption by the probe. The probe comprises a first and a second optical fiber that carry light to and from the probe, and a temperature sensor material, the absorbance of which changes with temperature, through which the light is directed. Light is directed through the first optical fiber, passes through the temperature sensor material, and is transmitted by a second optical fiber from the material to a detector. Temperature-dependent and temperature-independent factors are derived from measurements of the transmitted light intensity. For each sensor material, the temperature T is a function of the ratio, R, of these factors. The temperature function f(R) is found by applying standard data analysis techniques to plots of T versus R at a series of known temperatures. For a sensor having a known temperature function f(R) and known characteristic and temperature-dependent factors, the temperature can be computed from a measurement of R. Suitable sensor materials include neodymium-doped boresilicate glass, accurate to .+-.0.5.degree. C. over an operating temperature range of about -196.degree. C. to 400.degree. C.; and a mixture of D.sub.2 O and H.sub.2 O, accurate to .+-.0.1.degree. C. over an operating range of about 5.degree. C. to 90.degree. C.

O'Rourke, Patrick E. (Martinez, GA); Livingston, Ronald R. (Aiken, SC); Prather, William S. (Augusta, GA)

1994-01-01

158

Sensorless temperature estimation and control of Peltier devices  

E-print Network

Peltier devices, also known as thermoelectric devices (TEDs), are solid state junctions of two dissimilar materials in which heat transfer and electrical conduction are coupled. A current running through a TED causes heat ...

Odhner, Lael Ulam, 1980-

2006-01-01

159

Spectroscopic temperature measurements in interior ballistic environments  

Microsoft Academic Search

Spectroscopic temperature measurements during the interior ballistic cycle of a 20 mm test fixture gun and inside the muzzle flash of a 7.62 mm rifle are described. The investigation yields information on temperature distribution in the burning propellant charge of the 20 mm test fixture and on radial temperature profiles in the 7.62 mm muzzle flash region. A technique to

G. Klingenberg; H. Mach

1984-01-01

160

Temperature measurement systems in wearable electronics  

NASA Astrophysics Data System (ADS)

The aim of this paper is to present the concept of temperature measurement system, adapted to wearable electronics applications. Temperature is one of the most commonly monitored factor in smart textiles, especially in sportswear, medical and rescue products. Depending on the application, measured temperature could be used as an initial value of alert, heating, lifesaving or analysis system. The concept of the temperature measurement multi-point system, which consists of flexible screen-printed resistive sensors, placed on the T-shirt connected with the central unit and the power supply is elaborated in the paper.

Walczak, S.; Go?ebiowski, J.

2014-08-01

161

Laser Spectroscopic Measurement Of Temperature And Density  

NASA Technical Reports Server (NTRS)

Report discusses research on use of laser-induced fluorescence in oxygen and Raman scattering in air for simultaneous measurement of temperature and density of air. Major application of laser spectroscopic techniques, measurement of fluctuations of temperature and density in hypersonic flows in wind tunnels.

Mckenzie, Robert L.; Laufer, Gabriel

1991-01-01

162

75 FR 11624 - Highway Safety Programs; Conforming Products List of Evidential Breath Alcohol Measurement Devices  

Federal Register 2010, 2011, 2012, 2013

...Conforming Products List of Evidential Breath Alcohol Measurement Devices AGENCY: National...Model Specifications for Evidential Breath Alcohol Measurement Devices (58 FR 48705...Standards for Devices to Measure Breath Alcohol (38 FR 30459). A Qualified...

2010-03-11

163

77 FR 35747 - Highway Safety Programs; Conforming Products List of Evidential Breath Alcohol Measurement Devices  

Federal Register 2010, 2011, 2012, 2013

...Conforming Products List of Evidential Breath Alcohol Measurement Devices AGENCY: National...Model Specifications for Evidential Breath Alcohol Measurement Devices dated, September...Standards for Devices to Measure Breath Alcohol (38 FR 30459). A Qualified...

2012-06-14

164

SHORT COMMUNICATION: Time measurement device with four femtosecond stability  

NASA Astrophysics Data System (ADS)

We present the experimental results of extremely precise timing in the sense of time-of-arrival measurements in a local time scale. The timing device designed and constructed in our laboratory is based on a new concept using a surface acoustic wave filter as a time interpolator. Construction of the device is briefly described. The experiments described were focused on evaluating the timing precision and stability. Low-jitter test pulses with a repetition frequency of 763 Hz were generated synchronously to the local time base and their times of arrival were measured. The resulting precision of a single measurement was typically 900 fs RMS, and a timing stability TDEV of 4 fs was achieved for time intervals in the range from 300 s to 2 h. To our knowledge this is the best value reported to date for the stability of a timing device. The experimental results are discussed and possible improvements are proposed.

Panek, Petr; Prochazka, Ivan; Kodet, Jan

2010-10-01

165

Methods of Measurement for Semiconductor Materials, Process Control, and Devices  

NASA Technical Reports Server (NTRS)

The development of methods of measurement for semiconductor materials, process control, and devices is reported. Significant accomplishments include: (1) Completion of an initial identification of the more important problems in process control for integrated circuit fabrication and assembly; (2) preparations for making silicon bulk resistivity wafer standards available to the industry; and (3) establishment of the relationship between carrier mobility and impurity density in silicon. Work is continuing on measurement of resistivity of semiconductor crystals; characterization of generation-recombination-trapping centers, including gold, in silicon; evaluation of wire bonds and die attachment; study of scanning electron microscopy for wafer inspection and test; measurement of thermal properties of semiconductor devices; determination of S-parameters and delay time in junction devices; and characterization of noise and conversion loss of microwave detector diodes.

Bullis, W. M. (ed)

1973-01-01

166

Nuclear temperature measurement for central collisions  

Microsoft Academic Search

Nuclear temperatures from double isotope yield ratios and excited state populations were measured for central ^86Kr + ^93Nb collision at 35 70 100 and 120 AMeV. Temperatures based on ^3He\\/^4He isotope ratio increase with beam energy while temperatures from excited state populations remain nearly constant around 4-5 MeV. Temperatures from the double isotope yield based on ^11C\\/^12C ratio are consistent

H. Xi; G. J. Kunde; R. Shomin; O. Bjarki; S. Fritze; C. K. Gelbke; C. Gross; J. Imme; R. C. Lemmon; W. G. Lynch; A. Nadason; C. Nociforo; V. Maddalena; D. Magestro; T. Odeh; R. Popescu; G. Raciti; G. Riccobene; P. Romano; A. Saija; C. Schwarz; C. Sfienti; M. B. Tsang; A. M. Vandermolen; G. D. Westfall; L. W. Weathers

1998-01-01

167

Local temperature control of photonic crystal devices via micron-scale electrical heaters  

E-print Network

Local temperature control of photonic crystal devices via micron-scale electrical heaters Andrei to locally control the temperature of photonic crystal devices via micron-scale electrical heaters switching. We have already reported a method to locally control the temperature of pho- tonic crystal

Faraon, Andrei

168

A simple method for accurate temperature measurement.  

PubMed

A simple method, employing thermocouples, was developed for measurement of temperature with an accuracy of 0.05 degrees C. The method is based on the principle of a compensatory measurement of the thermocouple voltage, with application of an additional amplifier. The temperature level of the reference thermocouple was shifted from 0 degrees to 37 degrees C, using a compensating voltage. Within a smaller range (37 degrees -- 43 degrees C) the voltage of the measuring thermocouple was additionally amplified, which resulted in an increase in sensitivity and accuracy of the temperature measurement in animal tissues. The electronic circuit and calibration procedure are presented in detail. PMID:7446155

Grucza, R; Boruta, E

1980-01-01

169

Temperature Sensitive Particle for Velocity and Temperature Measurement.  

NASA Astrophysics Data System (ADS)

Phosphorescence and fluorescence are often applied to measure the temperature and the concentration of oxygen. The intensity and the lifetime of phosphor depend on the temperature and the oxygen concentration, due to the quenching effect of the phosphor. The present study clarified the effects of temperature on the lifetime of phosphorescence of Porphyrins, Ru(bpy)3^2+ and the europium complex. The phosphorescence lifetime of oil solution / water solution / painted wall were measured with changing temperature and oxygen concentration. In addition, the optical property of the small particles incorporated with the europium complex was investigated in the oil/water. The lifetime was strongly affected by temperature. Then, the temperature sensitive particle (TSParticle) with metal complex was applied to measure temperature in Silicone oil (10cSt) two-dimensionally. Present study is the result of ?High speed three-dimensional direct measurement technology development for the evaluation of heat flux and flow of liquid metal? entrusted to the University of Tokyo by the Ministry of Education, Culture, Sports, Science and Technology of Japan(MEXT).

Someya, Satoshi; Okamoto, Koji; Iida, Masao

2007-11-01

170

Experimental measurement-device-independent quantum key distribution.  

PubMed

Quantum key distribution is proven to offer unconditional security in communication between two remote users with ideal source and detection. Unfortunately, ideal devices never exist in practice and device imperfections have become the targets of various attacks. By developing up-conversion single-photon detectors with high efficiency and low noise, we faithfully demonstrate the measurement-device-independent quantum-key-distribution protocol, which is immune to all hacking strategies on detection. Meanwhile, we employ the decoy-state method to defend attacks on a nonideal source. By assuming a trusted source scenario, our practical system, which generates more than a 25 kbit secure key over a 50km fiber link, serves as a stepping stone in the quest for unconditionally secure communications with realistic devices. PMID:24116758

Liu, Yang; Chen, Teng-Yun; Wang, Liu-Jun; Liang, Hao; Shentu, Guo-Liang; Wang, Jian; Cui, Ke; Yin, Hua-Lei; Liu, Nai-Le; Li, Li; Ma, Xiongfeng; Pelc, Jason S; Fejer, M M; Peng, Cheng-Zhi; Zhang, Qiang; Pan, Jian-Wei

2013-09-27

171

Measurement and modeling of time- and spatial-resolved wafer surface temperature in inductively coupled plasmas  

Microsoft Academic Search

The transient temperature profile across a commercial wafer temperature sensor device in an inductively coupled Ar plasma is reported. The measured temperatures are compared to model predictions, based on a coupled plasma-wafer model. The radial temperature profile is the result of the radial profile in the ion energy flux. The ion energy flux profile is obtained by combining the Langmuir

C. C. Hsu; M. J. Titus; D. B. Graves

2007-01-01

172

A two-thermocouples probe for radiation corrections of measured temperatures in compartment fires  

Microsoft Academic Search

Bare-bead thermocouples are widely used for measuring temperature fields in compartment fires. It is well-known that temperature readings using such a device can be significantly affected by radiation errors, the apparent thermocouple junction temperature being thus different from the true gas temperature. However, a probe consisting of two thermocouples of unequal diameters, but made of the same material can be

S Brohez; C Delvosalle; G Marlair

2004-01-01

173

Nonintrusive temperature measurements on advanced turbomachinery components  

SciTech Connect

A nonintrusive, noncontacting method we developed for temperature measurements in hostile environments is well-suited for measurements on advanced turbine components. The method is not only superior to thermocouples in sufficiently difficult environments, but also is the only known method for making measurements in situations where no form of pyrometry works. We demonstrated the method, which uses laser-induced fluorescence of thermographic phosphors bonded to the component surfaces, on turbine blades and vanes in developmental turbine engines. The method is extendable to the much-higher temperatures expected inside advanced turbomachinery. Of particular note is the adaptability of the method to surface-temperature measurements on ceramics operating at high temperatures. In this temperature range, the ceramics become translucent, and surface emissivity becomes meaningless. We shall discuss the method, its advantages and limitations, recent test results on operating turbine engines, and the extension to ceramic components.

Noel, B.W. [Los Alamos National Lab., NM (United States); Turley, W.D.; Lewis, W. [EG and G Energy Measurements, Inc., Goleta, CA (United States)

1992-12-31

174

Nulling Infrared Radiometer for Measuring Temperature  

NASA Technical Reports Server (NTRS)

A nulling, self-calibrating infrared radiometer is being developed for use in noncontact measurement of temperature in any of a variety of industrial and scientific applications. This instrument is expected to be especially well-suited to measurement of ambient or near-ambient temperature and, even more specifically, for measuring the surface temperature of a natural body of water. Although this radiometer would utilize the long-wavelength infrared (LWIR) portion of the spectrum (wavelengths of 8 to 12 m), its basic principle of operation could also be applied to other spectral bands (corresponding to other temperature ranges) in which the atmosphere is transparent and in which design requirements for sensitivity and temperature-measurement accuracy could be satisfied.

Ryan, Robert

2003-01-01

175

Pitot tube as a calibration device for turbulence measurement  

NASA Astrophysics Data System (ADS)

It is demonstrated that a pitot tube can be used to calibrate hot-wire turbulence measurements. Expressions are given that make it possible to correct hot-wire measurements for the effects of the tangential velocity component and high turbulence intensity by using a pitot tube to measure the mean velocity in fully developed turbulent pipe flow. It is suggested that the pitot tube can also be used as a calibration device for LDA, by measuring mean uv values with an LDA and comparing results with pitot-tube measurements.

Kassab, Sadek Z.

1990-06-01

176

Spectroscopic temperature measurements in a ? microwave discharge  

Microsoft Academic Search

We report temperature measurements in a low-pressure hydrogen microwave plasma. Translational temperatures both of H and of 0022-3727\\/29\\/4\\/010\\/img2 (using Doppler broadening), as well as the rotational temperature of 0022-3727\\/29\\/4\\/010\\/img2, are simultaneously determined. It is first shown that the rotational temperature of the 0022-3727\\/29\\/4\\/010\\/img2 excited 0022-3727\\/29\\/4\\/010\\/img5 state is not in equilibrium with the translational temperatures of the neutral particles. Then, using

L. Tomasini; A. Rousseau; G. Gousset; P. Leprince

1996-01-01

177

Atmospheric temperature measurements, using Raman lidar  

NASA Technical Reports Server (NTRS)

The Raman-shifted return of a lidar system had been used to make atmospheric temperature measurements. The measurements were made along a horizontal path at temperatures ranging from -30 to 30 C and at ranges of about 100 meters. The temperature data were acquired by recording the intensity ratio of two portions of the rotational Raman spectrum, which were simultaneously sampled from a preset range. These tests verified that the theoretical predictions formulated in the design of the system were adequate. Measurements were made to an accuracy of + or - 4 C with 1-minute temporal resolution.

Salzman, J. A.; Coney, T. A.

1974-01-01

178

A low noise high-temperature superconducting quantum interference device  

SciTech Connect

Superconducting quantum interferences devices (SQUIDs) are useful for a number of applications such as magnetometers, high speed samplers, and RF amplifiers. In some applications, the advantage of a superconducting system is not sufficient to justify 4.2 K operation. However, a high T{sub c} implementation may be attractive. These active circuits demand Josephson junctions and other structures with tunable, well-understood properties. We have developed a process to fabricate step edge grain boundary junctions in YBa{sub 2}Cu{sub 3}O{sub 7} films on sapphire. Utilizing this process, we built low noise dc SQUIDs as well as other test structures. We designed an electron beam evaporator to grow the superconducting thin films in-situ. I discuss the details of this system. I then explain the motivation for and properties of YBCO/MgO/Sapphire bilayers. I detail the fabrication of various SQUIDs and other test structures. The electrical properties were measured. Magnetic field response and noise are compared with standard theories.

Berezin, A.B.

1993-12-31

179

Fine Wire Thermocouple Measurements of Fluctuating Temperature  

Microsoft Academic Search

A technique for the measurement of the statistics of the temperature fluctuation, notably probability density function and power spectrum, in turbulent diffusion flames which employs fine wire thermocouples, compensated for the effects of thermal inertia, is assessed. Measurements made in an open turbulent methane diffusion flame are reported and compared, from the standpoint of identifying the interaction between measurement technique

A. BALLANTYNE; J. B. MOSS

1977-01-01

180

Solar absorber material reflectivity measurements at temperature  

SciTech Connect

Assessment of absorber shell material properties at high operating temperatures is essential to the full understanding of the solar energy absorption process in a solar thermal rocket. A review of these properties, their application and a new experimental methodology to measure them at high temperatures is presented. The direct application for the research is absorber cavity development for a Solar Thermal Upper Stage (STUS). High temperature measurements, greater than 1,000 Kelvin, are difficult to obtain for incident radiation upon a solid surface that forms an absorber cavity in a solar thermal engine. The basic material properties determine the amount of solar energy that is absorbed, transmitted or reflected and are dependent upon the material's temperature. This investigation developed a new approach to evaluate the material properties (i.e., reflectivity, absorptive) of the absorber wall and experimentally determined them for rhenium and niobium sample coupons. The secular reflectivity was measured both at room temperature and at temperatures near 1,000 Kelvin over a range of angles from 0 to 90 degrees. The same experimental measurements were used to calculate the total reflectivity of the sample by integrating the recorded intensities over a hemisphere. The test methodology used the incident solar energy as the heating source while directly measuring the reflected light (an integrated value over all visible wavelengths). Temperature dependence on total reflectivity was found to follow an inverse power function of the material's temperature.

Bonometti, J.A.; Hawk, C.W.

1999-07-01

181

IN SITU FIELD PORTABLE FINE PARTICLE MEASURING DEVICE  

EPA Science Inventory

The report describes the design, development, and testing of an in situ fine particle measuring device--the Fine Particle Stack Spectrometer System (FPSSS). It is a laser-fed optical system with detection by near-forward light scattering. Sample volume is established by a high-re...

182

Designing and Constructing an Aerodynamic Drag Coefficient Measuring Device  

Microsoft Academic Search

Four main factors are known to have an effect on the drag of free falling bodies. These factors are: shape, size, density of the body and density of the medium through which the body travels. This work aims to design and construct a device to measure the drag coefficient for the free falling bodies in different fluid mediums. To achieve

Fawaz Abbas Najim; Adnan A. Al-Qalamchi; Haydar Hassan Balla

183

Drag devices for two-phase mass flow measurements  

Microsoft Academic Search

Full flow drag devices were tested in steady state air-water mixtures and transient steam-water mixtures in order to obtain two-phase mass flow measurements. Modeling methods for obtaining mass flow rates are discussed along with the effects of two-phase flows on the drag coefficient of full flow multihole drag plates.

J. L. Anderson

1979-01-01

184

Nanoscale displacement measurement of MEMS devices using fiber optic interferometry  

Microsoft Academic Search

In this paper, the application of fiber interferometry in the nano-scale displacement measurement of microelectromechanical system (MEMS) device is being presented. Fiber optic interferometry combines the benefits of the optical fiber such as lightweight, small size and wide bandwidth with the high resolution, high sensitivity capability of the interferometry. It also provides easier setup and offers lower energy loss than

Chee Wei Lee; Xuming Zhang; Swee Chuan Tjin; Ai Qun Liu

2003-01-01

185

ALMA front end amplitude calibration device design and measured performances  

Microsoft Academic Search

This paper summarizes the main aspects of the design and qualification test results of the ALMA Amplitude Calibration Device Robotic Arm (ACD). The design aspects of the ACD, including a detailed description of the components selected to achieve the expected performances are presented in the first part of the paper. Also the system performances results measured in the first prototype

Joan Manel Casalta; Albert Molins; Mart Bassas; Manuel Canchado; Eva Creus; Albert Toms

2008-01-01

186

Capacitance-voltage measurement in memory devices using ferroelectric polymer  

NASA Astrophysics Data System (ADS)

Application of thin polymer film as storing mean for non-volatile memory devices is investigated. Capacitance-voltage (C-V) measurement of metal-ferroelectric-metal device using ferroelectric copolymer P(VDF-TrFE) as dielectric layer shows stable 'butter-fly' curve. The two peaks in C-V measurement corresponding to the largest capacitance are coincidental at the coercive voltages that give rise to zero polarization in the polarization hysteresis measurement. By comparing data of C-V and P-E measurement, a correlation between two types of hysteresis is established in which it reveals simultaneous electrical processes occurring inside the device. These processes are caused by the response of irreversible and reversible polarization to the applied electric field that can be used to present a memory window. The memory effect of ferroelectric copolymer is further demonstrated for fabricating polymeric non-volatile memory devices using metal-ferroelectric-insulator-semiconductor structure (MFIS). By applying different sweeping voltages at the gate, bidirectional flat-band voltage shift is observed in the ferroelectric capacitor. The asymmetrical shift after negative sweeping is resulted from charge accumulation at the surface of Si substrate caused by the dipole direction in the polymer layer. The effect is reversed for positive voltage sweeping.

Nguyen, Chien A.; Lee, Pooi See

2006-01-01

187

Fast amplitude and delay measurement for characterization of optical devices  

E-print Network

to determine the chromatic dispersion in the device under test by taking the derivative of the group delay with respect to optical wavelength. The measurement setup allows both step-tunable and sweeping laser sources. A modulation frequency of up to 2.7 GHz...

Thompson, Michael Thomas

2006-10-30

188

Dynamic temperature measurements with embedded optical sensors.  

SciTech Connect

This report summarizes LDRD project number 151365, %5CDynamic Temperature Measurements with Embedded Optical Sensors%22. The purpose of this project was to develop an optical sensor capable of detecting modest temperature states (<1000 K) with nanosecond time resolution, a recurring diagnostic need in dynamic compression experiments at the Sandia Z machine. Gold sensors were selected because the visible re ectance spectrum of gold varies strongly with temperature. A variety of static and dynamic measurements were performed to assess re ectance changes at di erent temperatures and pressures. Using a minimal optical model for gold, a plausible connection between static calibrations and dynamic measurements was found. With re nements to the model and diagnostic upgrades, embedded gold sensors seem capable of detecting minor (<50 K) temperature changes under dynamic compression.

Dolan, Daniel H.,; Seagle, Christopher T; Ao, Tommy

2013-10-01

189

Spectroscopic temperature measurements in oxygen discharges  

Microsoft Academic Search

The rotational temperature of the excited state O2 (b1 Sigma g+, v=0) in an oxygen glow discharge is measured from the intensity distribution of the atmospheric A-band O2 (b1 Sigma g+, v=0) to O2(X3 Sigma g-, v=0) at lambda =760 nm. The kinetic temperature, often called the gas temperature is also deduced using vacuum ultraviolet absorption spectroscopy in the same

M. Touzeau; M. Vialle; A. Zellagui; G. Gousset; M. Lefebvre; M. Pealat

1991-01-01

190

Transient temperature measurement using embedded thermocouples  

Microsoft Academic Search

The response time of thermocouples is generally considered to be a limiting factor when transient temperature changes need to be assessed in solids. As an example, transient temperature changes which develop during dynamic straining of materials, adiabatic shear band formation, dynamic fracture and related fields are often investigated using sophisticated noncontact measurement techniques such as infrared detectors. In these phenomena,

D. Rittel

1998-01-01

191

Ways to measure body temperature in the field.  

PubMed

Body temperature (Tb) represents one of the key parameters in ecophysiological studies with focus on energy saving strategies. In this study we therefore comparatively evaluated the usefulness of two types of temperature-sensitive passive transponders (LifeChips and IPTT-300) and one data logger (iButton, DS1922L) mounted onto a collar to measure Tb in the field. First we tested the accuracy of all three devices in a water bath with water temperature ranging from 0 to 40C. Second, we evaluated the usefulness of the LifeChips and the modified iButtons for measuring Tb of small heterothermic mammals under field conditions. For this work we subcutaneously implanted 14 male edible dormice (Glis glis) with transponders, and equipped another 14 males with data loggers to simultaneously record Tb and oxygen consumption with a portable oxygen analyzer (Oxbox). In one individual we recorded Tb with both devices and analyzed recorded Tb patterns. LifeChips are able to measure temperature within the smallest range from 25 to 40C with an accuracy of 0.070.12C. IPTT-300 transponders measured temperature between 10 and 40C, but accuracy decreased considerably at values below 30C, with maximal deviations of nearly 7C. An individual calibration of each transponder is therefore needed, before using it at low Tbs. The accuracy of the data logger was comparatively good (0.120.25C) and stable over the whole temperature range tested (0-40C). In all three devices, the repeatability of measurements was high. LifeChip transponders as well as modified iButtons measured Tb reliably under field conditions. Simultaneous Tb-recordings in one edible dormouse with an implanted LifeChip and a collar-mounted iButton revealed that values of both measurements were closely correlated. Taken together, we conclude that implanted temperature-sensitive transponders represent an appropriate and largely non-invasive method to measure Tb also under field conditions. PMID:24802148

Langer, Franz; Fietz, Joanna

2014-05-01

192

Experimental measurement-device-independent quantum key distribution  

E-print Network

Throughout history, every advance in encryption has been defeated by advances in hacking with severe consequences. Quantum cryptography holds the promise to end this battle by offering unconditional security when ideal single-photon sources and detectors are employed. Unfortunately, ideal devices never exist in practice and device imperfections have become the targets of various attacks. By developing up-conversion single-photon detectors with high efficiency and low noise, we build up a measurement-device-independent quantum key distribution (MDI-QKD) system, which is immune to all hacking strategies on detection. Meanwhile, we employ the decoy-state method to defeat attacks on non-ideal source. By closing the loopholes in both source and detection, our practical system, which generates more than 25 kbit secure key over a 50-km fiber link, provides an ultimate solution for communication security.

Yang Liu; Teng-Yun Chen; Liu-Jun Wang; Hao Liang; Guo-Liang Shentu; Jian Wang; Ke Cui; Hua-Lei Yin; Nai-Le Liu; Li Li; Xiongfeng Ma; Jason S. Pelc; M. M. Fejer; Qiang Zhang; Jian-Wei Pan

2012-09-27

193

Simultaneous Measurement of Temperature Dependent Thermophysical Properties  

NASA Astrophysics Data System (ADS)

A new evaluation method for a transient measurement of thermophysical properties is presented in this paper. The aim of the research was to couple a new automatic evaluation procedure to the BICOND thermophysical property measurement method to enhance the simultaneous determination of the temperature dependent thermal conductivity and volumetric heat capacity. The thermophysical properties of two different polymers were measured and compared with the literature data and with the measurement results that were done by well-known, traditional methods. The BICOND method involves a step-down cooling, recording the temperature histories of the inner and the outer surfaces of a hollow cylindrical sample and the thermophysical properties are evaluated from the solution of the corresponding inverse heat conduction using a genetic algorithm-based method (BIGEN) developed by the authors. The BIGEN is able to find the material properties with any kind of temperature dependency, that is illustrated through the measurement results of poly(tetrafluoroethylene) (PTFE) and polyamide (PA) samples.

Czl, Balzs; Grf, Gyula; Kiss, Lszl

2011-11-01

194

Precision temperature gradient measurements on window glass  

NASA Technical Reports Server (NTRS)

Surface temperature gradients were measured with miniature thermocouples installed in a 58.5 cm (23-inch) square window. Test measurements at 25 locations were made under vacuum and with the window operating in radiant heat transfer mode. The analysis of thermocouple design and installation is presented along with a lead wire routing scheme to allow for both differential and absolute temperature measurements while using a minimum number of signal feedthru paths through the test chamber wall. Typical test data and operational precautions are presented along with the accuracy analysis for installation effects and measurement effects to support differential temperature measurement precision values of + or - 0.06 C RMS + or - 0.1 F RMS).

Mikk, G.; Petrie, W.

1977-01-01

195

Methods of measurement for semiconductor materials, process control, and devices  

NASA Technical Reports Server (NTRS)

Significant accomplishments include development of a procedure to correct for the substantial differences of transistor delay time as measured with different instruments or with the same instrument at different frequencies; association of infrared response spectra of poor quality germanium gamma ray detectors with spectra of detectors fabricated from portions of a good crystal that had been degraded in known ways; and confirmation of the excellent quality and cosmetic appearance of ultrasonic bonds made with aluminum ribbon wire. Work is continuing on measurement of resistivity of semiconductor crystals; study of gold-doped silicon, development of the infrared response technique; evaluation of wire bonds and die attachment; and measurement of thermal properties of semiconductor devices, delay time and related carrier transport properties in junction devices, and noise properties of microwave diodes.

Bullis, W. M. (editor)

1972-01-01

196

Research and development of measurement device for thermal conductivity of nanofluids  

NASA Astrophysics Data System (ADS)

This research aims to develop a device for measuring thermal conductivity of nanofluid using transient hot-wire methodology. The proposed measurement system comprises of sensing wires coupled with an electrical measurement unit kept in a constant-temperature environment. The wires are made of nickel-chromium alloy a coating with Teflon for insulation. Enhanced ratio of thermal conductivity in a nanofluid is calculated from the difference in electrical parameters with and without CuO nanoparticles added. The results show that thermal conductivities are enhanced by 5.8% and 9.6% when CuO nanoparticles of 1.1%wt and 2.2%wt are added, respectively. Resultant data was then compared with that obtained by two other measurement devices. The difference in measurements was within 5%. This proves that the system developed in this study can perform effective measurement of thermal conductivity of nanofluids.

Jwo, C. S.; Teng, T. P.; Hung, C. J.; Guo, Y. T.

2005-01-01

197

NaOH-based high temperature heat-of-fusion thermal energy storage device  

NASA Technical Reports Server (NTRS)

A material called Thermkeep, developed as a low-cost method for the storage of thermal energy for solar electric power generating systems is discussed. The storage device consists of an insulated cylinder containing Thermkeep in which coiled tubular heat exchangers are immersed. A one-tenth scale model of the design contains 25 heat-exchanger tubes and 1500 kg of Thermkeep. Its instrumentation includes thermocouples to measure internal Thermkeep temperatures, vessel surface, heated shroud surface, and pressure gauges to indicate heat-exchanger pressure drops. The test-circuit design is presented and experimental results are discussed.

Cohen, B. M.; Rice, R. E.

1978-01-01

198

Graphene, a material for high temperature devices intrinsic carrier density, carrier  

E-print Network

Graphene, a material for high temperature devices � intrinsic carrier density, carrier drift 3.87 3 106 cm22 K22 ?T2 ), carrier drift velocity, and G mode phonon energy of graphene devices and their temperature dependencies up to 2400 K. Our results show intrinsic carrier density of graphene is an order

Wang, Wei Hua

199

SHOCK TUBE SPECTROSCOPY. II. SPECTROSCOPIC TEMPERATURE AND INTENSITY MEASUREMENTS IN A SHOCK TUBE. Scientific Report No. 3  

Microsoft Academic Search

Spectroscopic rotational temperature measurements on the (0,1) band of ; the CN violet system gave temperatures which agree with the calculated gas ; kinetic temperature to about 10%. This method provided a means of inferring a ; temperature without introducing temperature sensitive devices such as probes in ; the environment. Rotational intensity measurements on the (0,0) Aln band of the

W. H. Parkinson; R. W. Nicholls

1959-01-01

200

Floating Probe Assembly for Measuring Temperature of Water  

NASA Technical Reports Server (NTRS)

A floating apparatus denoted a temperature probe aquatic suspension system (TPASS) has been developed for measuring the temperature of an ocean, lake, or other natural body of water at predetermined depths. Prior instruments built for the same purpose were found to give inaccurate readings because the apparatuses themselves significantly affected the temperatures of the water in their vicinities. The design of the TPASS is intended to satisfy a requirement to minimize the perturbation of the temperatures to be measured. The TPASS includes a square-cross-section aluminum rod 28 in. (=71 cm) long with floats attached at both ends. Each float includes five polystyrene foam disks about 3/4 in.(=1.9 cm) thick and 2.5 in. (=6.4 cm) in diameter. The disks are stacked to form cylinders, bolted to the rod, and covered with hollow plastic sleeves. A metal sleeve is clamped to the middle of the aluminum rod, from whence it hangs down into the water. Temperature probes (which can be thermocouples, thermistors, or resistance temperature devices) are placed within the sleeve at the desired measurement depths. Wires from the temperature probes are routed to the input terminals of a data logger.

Stewart, Randy; Ruffin, Clyde

2002-01-01

201

Floating Probe Assembly for Measuring Temperature of Water  

NASA Technical Reports Server (NTRS)

A floating apparatus denoted a temperature probe aquatic suspension system (TPASS) has been developed for measuring the temperature of an ocean, lake, or other natural body of water at predetermined depths. Prior instruments built for the same purpose were found to give inaccurate readings because the apparatuses themselves significantly affected the temperatures of the water in their vicinities. The design of the TPASS is intended to satisfy a requirement to minimize the perturbation of the temperatures to be measured. The TPASS includes a square-cross-section aluminum rod 28 in. (approx. = 71 cm) long with floats attached at both ends. Each float includes five polystyrene foam disks about 3/4 in. (approx. = 1.9 cm) thick and 2.5 in. (approx. = 6.4 cm) in diameter. The disks are stacked to form cylinders, bolted to the rod, and covered with hollow plastic sleeves. A metal sleeve is clamped to the middle of the aluminum rod, from whence it hangs down into the water. Temperature probes (which can be thermocouples, thermistors, or resistance temperature devices) are placed within the sleeve at the desired measurement depths. Wires from the temperature probes are routed to the input terminals of a data logger. This work was done by Randy

Selinsky, T.; Stewart, Randy; Ruffin, Clyde

2002-01-01

202

A Microwave Radiometer for Internal Body Temperature Measurement  

NASA Astrophysics Data System (ADS)

This thesis presents the analysis and design of a microwave radiometer for internal body temperature measurements. There is currently no available method for non-invasive temperature measurement inside the human body. However, knowledge of both relative and absolute temperature variations over time is important to a number of medical applications. The research presented in this thesis details a proof-of-concept near-field microwave radiometer demonstrating relative thermometry of a multi-layer phantom. There are a number of technical challenges addressed in this thesis for radiometric determination of sub-degree temperature variations in the human body. A theoretical approach is developed for determining sensing depth from known complex layered tissues, which is defined as a figure of merit, and is shown to be dependent on frequency, electrical properties of the tissues, and the near-field probe. In order to obtain depth resolution, multiple frequency operation can be used, so multi-frequency probes are designed and demonstrated in this work. The choice of frequencies is determined not only by the tissue material properties, but also by the ever increasing radio interference in the environment. In this work, quiet bands allocated to radio astronomy are investigated. The radiometer and probe need to be compact to be wearable, and several advancements are made towards a fully wearable device: multi-frequency low-profile probes are designed and fabricated on a flexible substrate and the process of on-chip integration is demonstrated by a GaAs MMIC cold noise source for radiometer calibration. The implemented proof-of-concept device consists of two radiometers at 1.4 GHz and 2.7 GHz, designed with commercial inexpensive devices that can enable sufficient sensitivity. The device is tested on a phantom with two water layers whose temperatures are varied in a controlled manner, and focused on the human body temperature range. Measured results are discussed qualitatively as they relate to circadian rhythm monitoring. Finally, the thesis identifies future research that is required to make a practical wearable microwave thermometer for internal body temperature measurements.

Scheeler, Robert Patterson

203

Universal measurement device for electronic watches and small clocks  

NASA Astrophysics Data System (ADS)

The project and the device set up for performing automatic measurements are described. The system development involved: a specially designed acquisition card, a standard personal computer and specific management programs. It is designed as laboratory equipment and is able to perform most of measurements required by electronic watchmaking industry such as current/consumption measurements, frequency, torque, motor pulses generation. Versions meeting specific production testing needs at reasonable costs can be developed. For after sale servicing, it is possible to deliver a diskette giving all parameters needed for a specific movement, avoiding changes in hardware.

Vermot, Michel

204

INFRARED TECHNIQUES FOR TEMPERATURE MEASUREMENT IN PLASMAJETS  

Microsoft Academic Search

The application of monochromatic radiation pyrometry to measurement of ; plasma temperatures was investigated. Infrared emission and absorption spectra ; of N, Ar, and He plasmajets, with vantuus admixtures, were measured. Strong ; infrared emission was observed in various lines and bands in the plasma spectra, ; extending from the visible region to 7.0 mu . The observed infrared absorption

Tourin

1962-01-01

205

The insertion device magnetic measurement facility: Prototype and operational procedures  

SciTech Connect

This report is a description of the current status of the magnetic measurement facility and is a basic instructional manual for the operation of the facility and its components. Please refer to the appendices for more detailed information about specific components and procedures. The purpose of the magnetic measurement facility is to take accurate measurements of the magnetic field in the gay of the IDs in order to determine the effect of the ID on the stored particle beam and the emitted radiation. The facility will also play an important role when evaluating new ideas, novel devices, and inhouse prototypes as part of the ongoing research and development program at the APS. The measurements will be performed with both moving search coils and moving Hall probes. The IDs will be evaluated by computer modeling of the emitted radiation for any given (measured) magnetic field map. The quality of the magnetic field will be described in terms of integrated multipoles for the effect on Storage Ring performance and in terms of the derived trajectories for the emitted radiation. Before being installed on the Storage Ring, every device will be measured and characterized to assure that it is compatible with Storage Ring requirements and radiation specifications. The accuracy that the APS needs to achieve for magnetic measurements will be based on these specifications.

Burkel, L.; Dejus, R.; Maines, J.; O'Brien, J.; Vasserman, I. (Argonne National Lab., IL (United States). Advanced Photon Source Accelerator Systems Div.); Pfleuger, J. (Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany). Hamburger Synchrotronstrahlungslabor)

1993-03-01

206

High temperature optical strain measurement system  

NASA Technical Reports Server (NTRS)

A high temperature strain measurement system being developed at the NASA Lewis Research Center utilizes laser speckle shift relations to measure strain components on the surface of a hot specimen in near real time. Features of this system include a totally noncontacting measurement capability and a rotatable gauge axis, allowing an optical rosette to be implemented and principal strains to be determined. Preliminary results and background work are presented.

Lant, Christian T.

1988-01-01

207

Measurement-Device-Independent Quantum Key Distribution over 200km.  

PubMed

Measurement-device-independent quantum key distribution (MDIQKD) protocol is immune to all attacks on detection and guarantees the information-theoretical security even with imperfect single-photon detectors. Recently, several proof-of-principle demonstrations of MDIQKD have been achieved. Those experiments, although novel, are implemented through limited distance with a key rate less than 0.1??bit/s. Here, by developing a 75MHz clock rate fully automatic and highly stable system and superconducting nanowire single-photon detectors with detection efficiencies of more than 40%, we extend the secure transmission distance of MDIQKD to 200km and achieve a secure key rate 3 orders of magnitude higher. These results pave the way towards a quantum network with measurement-device-independent security. PMID:25415890

Tang, Yan-Lin; Yin, Hua-Lei; Chen, Si-Jing; Liu, Yang; Zhang, Wei-Jun; Jiang, Xiao; Zhang, Lu; Wang, Jian; You, Li-Xing; Guan, Jian-Yu; Yang, Dong-Xu; Wang, Zhen; Liang, Hao; Zhang, Zhen; Zhou, Nan; Ma, Xiongfeng; Chen, Teng-Yun; Zhang, Qiang; Pan, Jian-Wei

2014-11-01

208

Integrated seal for high-temperature electrochemical device  

DOEpatents

The present invention provides electrochemical device structures having integrated seals, and methods of fabricating them. According to various embodiments the structures include a thin, supported electrolyte film with the electrolyte sealed to the support. The perimeter of the support is self-sealed during fabrication. The perimeter can then be independently sealed to a manifold or other device, e.g., via an external seal. According to various embodiments, the external seal does not contact the electrolyte, thereby eliminating the restrictions on the sealing method and materials imposed by sealing against the electrolyte.

Tucker, Michael C; Jacobson, Craig P

2013-07-16

209

Drag devices for two-phase mass flow measurements  

Microsoft Academic Search

Results are presented from testing a number of full-flow drag devices in steady-state air-water mixtures and transient steam-water mixtures for the purpose of obtaining two-phase mass flow measurements. Modeling methods for obtaining mass flow rates are discussed, along with the effects of two-phase flows on the drag coefficient of full-flow, multihole drag plates. Test results indicate that for applications in

1980-01-01

210

ALMA front end amplitude calibration device design and measured performances  

NASA Astrophysics Data System (ADS)

This paper summarizes the main aspects of the design and qualification test results of the ALMA Amplitude Calibration Device Robotic Arm (ACD). The design aspects of the ACD, including a detailed description of the components selected to achieve the expected performances are presented in the first part of the paper. Also the system performances results measured in the first prototype units are summarized at the last part of the paper.

Casalta, Joan Manel; Molins, Albert; Bassas, Mart; Canchado, Manuel; Creus, Eva; Toms, Albert

2008-07-01

211

Accuracy analysis of the space shuttle solid rocket motor profile measuring device  

NASA Technical Reports Server (NTRS)

The Profile Measuring Device (PMD) was developed at the George C. Marshall Space Flight Center following the loss of the Space Shuttle Challenger. It is a rotating gauge used to measure the absolute diameters of mating features of redesigned Solid Rocket Motor field joints. Diameter tolerance of these features are typically + or - 0.005 inches and it is required that the PMD absolute measurement uncertainty be within this tolerance. In this analysis, the absolute accuracy of these measurements were found to be + or - 0.00375 inches, worst case, with a potential accuracy of + or - 0.0021 inches achievable by improved temperature control.

Estler, W. Tyler

1989-01-01

212

Surface temperature measurement of plasma facing components with active pyrometry  

NASA Astrophysics Data System (ADS)

In fusion devices like ITER, plasma facing components will be in metal, (Tungsten and Beryllium), with emissivity in the range of 0.1-0.4. Therefore, surface temperature monitoring by infrared system will become more challenging due to low emissivity and consequently non negligible reflected flux. The active pyrometry method proposed in this paper allows surface temperature measurements independently of reflected and parasitic fluxes. A local increase of the surface temperature (?T(t)~10 C) introduced by a transient heating source (pulsed or modulated) results in an additional component of the flux collected by the detector. A filtering of the signal allows extracting a temporal flux proportional only to the variation of the emitted flux. The ratio of simultaneous measurements at two wavelengths allows solving the unknown emissivity (same as for classical bicolour pyrometry). In this paper, it is described how the active pyrometry method is adapted to the surface temperature measurements of metallic PFCs independently of the reflected fluxes. Experimental results for carbon and tungsten samples are reported. Finally, it is shown how, by using the active pyrometry, the overall 2D standard IR perturbed by a reflected flux is corrected to recover the full 2D surface temperature close to the real surface temperature.

Amiel, S.; Loarer, T.; Pocheau, C.; Roche, H.; Aumeunier, M. H.; Gauthier, E.; Le Niliot, C.; Rigollet, F.

2012-11-01

213

Epidermal photonic devices for quantitative imaging of temperature and thermal transport characteristics of the skin  

NASA Astrophysics Data System (ADS)

Characterization of temperature and thermal transport properties of the skin can yield important information of relevance to both clinical medicine and basic research in skin physiology. Here we introduce an ultrathin, compliant skin-like, or epidermal, photonic device that combines colorimetric temperature indicators with wireless stretchable electronics for thermal measurements when softly laminated on the skin surface. The sensors exploit thermochromic liquid crystals patterned into large-scale, pixelated arrays on thin elastomeric substrates; the electronics provide means for controlled, local heating by radio frequency signals. Algorithms for extracting patterns of colour recorded from these devices with a digital camera and computational tools for relating the results to underlying thermal processes near the skin surface lend quantitative value to the resulting data. Application examples include non-invasive spatial mapping of skin temperature with milli-Kelvin precision (50?mK) and sub-millimetre spatial resolution. Demonstrations in reactive hyperaemia assessments of blood flow and hydration analysis establish relevance to cardiovascular health and skin care, respectively.

Gao, Li; Zhang, Yihui; Malyarchuk, Viktor; Jia, Lin; Jang, Kyung-In; Chad Webb, R.; Fu, Haoran; Shi, Yan; Zhou, Guoyan; Shi, Luke; Shah, Deesha; Huang, Xian; Xu, Baoxing; Yu, Cunjiang; Huang, Yonggang; Rogers, John A.

2014-09-01

214

Spectroscopic temperature measurements in oxygen discharges  

Microsoft Academic Search

The rotational temperature values for the excited state O2 (b1Sigma(+) sub g, v = 0) were deduced from spectroscopic measurements made of the excited state of O2 in the positive column of an oxygen glow discharge at pressures between 0.5 and 5 torr and discharge current up to 100 mA. The rotational temperature of the excited state O2 was deduced

M. Touzeau; M. Vialle; A. Zellagui; G. Gousset; M. Lefebvre; M. Pealat

1992-01-01

215

Thin film thermocouples for high temperature measurement  

NASA Astrophysics Data System (ADS)

Thin film thermocouples have unique capabilities for measuring surface temperatures at high temperatures (above 800 K) under harsh conditions. Their low mass, approximately 2 x 10(-5) g/mm permits very rapid response and very little disturbance of heat transfer to the surface being measured. This has led to applications inside gas turbine engines and diesel engines measuring the surface temperature of first stage turbine blades and vanes and ceramic liners in diesel cylinders. The most successful high temperature (up to 1300 K) thin film thermocouples are sputter deposited from platinum and platinum-10 percent rhodium targets although results using base metal alloys, gold, and platinel will also be presented. The fabrication techniques used to form the thermocouples, approaches used to solve the high temperature insulation and adherence problems, current applications, and test results using the thin film thermocouples are reviewed. In addition a discussion will be presented on the current problems and future trends related to applications of thin film thermocouples at higher temperatures up to 1900 K.

Kreider, Kenneth G.

1989-05-01

216

Temperature measurements of shock-compressed deuterium  

SciTech Connect

The authors measured the temperatures of single and double-shocked D{sub 2} and H{sub 2} up to 85 GPa (0.85 Mbar) and 5,200 K. While single shock temperatures, at pressures to 23 GPa, agree well with previous models, the double shock temperatures are as much as 40% lower than predicted. This is believed to be caused by molecular dissociation, and a new model of the hydrogen EOS at extreme conditions has been developed which correctly predicts their observations. These data and model have important implications for programs which use condensed-phase hydrogen in implosion systems.

Holmes, N.C.; Ross, M.; Nellis, W.J.

1994-11-01

217

Methods of measurement for semiconductor materials, process control, and devices  

NASA Technical Reports Server (NTRS)

Activities directed toward the development of methods of measurement for semiconductor materials, process control, and devices are described. Topics investigated include: measurements of transistor delay time; application of the infrared response technique to the study of radiation-damaged, lithium-drifted silicon detectors; and identification of a condition that minimizes wire flexure and reduces the failure rate of wire bonds in transistors and integrated circuits under slow thermal cycling conditions. Supplementary data concerning staff, standards committee activities, technical services, and publications are included as appendixes.

Bullis, W. M. (editor)

1972-01-01

218

A spinal fixation device for in vivo load measurement.  

PubMed

An instrumented spinal fixation device has been developed that allows in vivo measurement of the forces and moments acting on the implant. The telemetry is inductively powered, hermetically sealed by electron beam welding and is active only during the measurements. The instrumented fixateur interne is similar in size to the original Dick internal fixator implant and has the strength of the original implant. Laboratory tests with paired implants mounted in plastic vertebrae show that small changes in the position of the implants have a strong influence on the distribution of the loads on the implants. PMID:8063846

Rohlmann, A; Bergmann, G; Graichen, F

1994-07-01

219

SiC device development for high temperature sensor applications  

NASA Technical Reports Server (NTRS)

Progress made in the processing and characterization of 3C-SiC for high temperature sensor applications is reviewed. Piezoresistance properties of silicon carbide and the temperature coefficient of resistivity of n-type beta-SiC are presented. In addition, photoelectrical etching and dopant selective etch-stops in SiC and high temperature Ohmic contacts for n-type beta-SiC sensors are discussed.

Shor, J. S.; Goldstein, David; Kurtz, A. D.; Osgood, R. M.

1992-01-01

220

Non-contact temperature measurement requirements  

NASA Technical Reports Server (NTRS)

The Marshall Space Flight Center is involved with levitation experiments for Spacelab, Space Station, and drop tube/tower operations. These experiments have temperature measurement requirements, that of course must be non-contact in nature. The experiment modules involved are the Acoustic Levitator Furnace (ALF), and the Modular Electromagnetic Levitator (MEL). User requirements of the ALF and drop tube are presented. The center also has temperature measurement needs that are not microgravity experiment oriented, but rather are related to the propulsion system for the STS. This requirement will also be discussed.

Higgins, D. B.; Witherow, W. K.

1989-01-01

221

Measurement of protection factor of respiratory protective devices toward nanoparticles.  

PubMed

The use of nanoparticles in industry has increased spectacularly over the past few years. Additionally, nanoscale particles seem to be the cause of new professional exposure situations. Due to their size, these particles may build up within the respiratory tract and may even reach the nervous system via the nasal passages; for this reason, it is generally recommended to wear respiratory protective devices (RPDs) in situations where collective protection is impossible to implement or inadequate. Here, we present the test bench ETNA designed to study the efficiency of RPDs in the presence of nanoparticles. The results of the efficiency measurement of two RPDs for two positions (sealed and unsealed) on a Sheffield head, for two inhalation configurations (constant flow and cyclic flow), and for two different particle size distributions of NaCl aerosol (one centered on 13 nm and the other on 59 nm) are presented below. The measurements indicate that when the leaks are negligible at the interface mask/head, the efficiency of RPD is greater for nanoparticles. For major leaks, the device's protection factor changes independently of the size of the particles. Furthermore, no trends with respect to the effect of the respiration type (constant-flow and cyclic-flow tests) have been shown on the device's protection factor. PMID:22752098

Brochot, C; Michielsen, N; Chazelet, S; Thomas, D

2012-07-01

222

HEATRING -SMART INVESTIGATION OF TEMPERATURE IMPACT ON INTEGRATED CIRCUIT DEVICES  

E-print Network

at different temperatures usually the transistor area on the wafer is heated by external heat sources which directly controls the temperature of the investigated transistor area on the wafer, guaranteeing is to use an external heat source such as a thermo-chuck. A smart option is to use a heatring structure

Paris-Sud XI, Université de

223

Conditioning circuit for temperature and strain measurement  

E-print Network

application is import, ant. A thermocouple is made up of two dissimilar tnetal conductors joined at one end, usually called the hot or detecting junction, and connected to some emf measuring instrument such as a, millivoltmeter at the cold encl... of the conductors. The mcasurcd emf is normally compared to some reference such as the ice point. A typical system is shown schematically in Fig. 2. The basic circuit contains all the essential elements for making a temperature measurement. The thermocouple...

Patel, Aashit Mahendra

2012-06-07

224

Ion temperature measurements in the Maryland Spheromak  

SciTech Connect

Initial spectroscopic data from MS showed evidence of ion heating as deduced from the line widths of different ion species. Detailed measurements of OIV spectral emission line profiles in space and time revealed that heating takes place at early time, before spheromak formation and is occurring within the current discharge. The measured ion temperature is several times the electron temperature and cannot be explained by classical (Spitzer) resistivity. Classically, ions are expected to have lower temperatures than the electrons and therefore, lower temperatures than observed. High ion temperatures have been observed in different RFP`s and Spheromaks but are usually associated with relaxation to the Taylor state and occur in the sustainment phase. During formation, the current delivered to start the discharge is not axisymmetric and as a consequence, X-points appear in the magnetic flux. A two dimensional analysis predicts that magnetic reconnection occurring at an X-point can give rise to high ion heating rates. A simple 0-dimensional calculation showed that within the first 20 {mu}s, a conversion of mass flow kinetic energy into ion temperature could take place due to viscosity.

Gauvreau, J.L.

1992-12-31

225

In Situ and Satellite Measured Temperature Comparability  

NASA Technical Reports Server (NTRS)

Following the International Geophysical Year in the late 1950's, small meteorological rockets caught the interest of scientists as a potentially inexpensive method to obtain meteorological information (density, temperature, wind) above balloon-borne radiosonde altitudes. These small rocketsondes have served many important observational roles in terms of studies conducted of atmospheric structure and processes, enabling many new ideas about the atmosphere to emerge. Although no longer manufactured a small residual inventory of meteorological rocketsondes exist for specific research projects. The value of data from meteorological rocketsondes is without question but with their disappearance data from many different satellites are filling the need, some able to resolve high-altitude temperatures quite well. However, the rocketsonde vertical profile is more localized to the launch site whereas satellites move several kilometers per second. The objective of this presentation is to compare in situ temperature data with remotely measured/retrieved temperature data. There have been a number of U.S. conducted missions utilizing the passive falling sphere data that we use to verify the comparability of retrieved temperatures from these satellites. Missions, some as early as 1991, were conducted in polar, equatorial, and mid-latitude locations. An important aspect is that a single satellite profile compared to a falling sphere profile often does not agree while high density satellite measurements when averaged over an area near the rocketsonde data area seems to be in better agreement. Radiosonde temperature data are used in the analysis when appropriate

Schmidlin, F. J.; Goldberg, R. A.; Bedrick, Mary; Rose, R. Lynn

2011-01-01

226

Measuring electron temperature in the extended corona  

NASA Technical Reports Server (NTRS)

A technique for measuring electron temperature in the extended corona from the line profile of the electron scattered component of coronal H I Ly alpha produced by Thomson scattering of chromospheric Ly alpha emission is discussed. Because of the high thermal velocity of electrons at coronal temperatures (approximately 6800 km/s at T(sub e) = 1,500,000 K) the effect of nonthermal velocities and solar wind flows on the electron velocity distribution are negligible. However, the low electron mass which is responsible for the high thermal velocity also results in a very wide profile (approximately equal to 50 A). This wide profile, together with an intensity that is three orders of magnitude weaker than the resonantly scattered component of Ly alpha makes the direct measurement of T(sub e) a challenging observational problem. An evaluation of this technique based on simulated measurements is presented and the subsequent instrumental requirements necessary to make a meaningful determination of the electron temperature are discussed. Estimates of uncertainties in the measured electron temperature are related to critical instrument parameters such as grating stray light suppression.

Hassler, Donald M.; Gardner, L. D.; Kohl, John L.

1992-01-01

227

Fuel Centerline Temperature Measurements in NSRR Experiment.  

National Technical Information Service (NTIS)

The fuel centerline temperatures of NSRR standard fuel rods in pulse irradiations were measured with W-5% Re/W-26% Re thermocouples inserted in a centerline hole of the fuel pellets. Three different fuel rods were individually subjected to repeated energy...

T. Hoshi, T. Iwamura, S. Yanagihara, Y. Orita, T. Hosokawa

1978-01-01

228

Temperature measurement in an argon jet  

Microsoft Academic Search

A short review is given of spectroscopic temperature measurements in ; argon plasma jets. Two regions were observed in the jet, a bright core and a far ; less radiating outer zone. In the spectrum of the core, continuous radiation and ; neutral argon lines are present. The broadening of the lines decreases rapidly ; in the passage to the

Slechta

1973-01-01

229

Dynamic gas temperature measurement system, volume 1  

NASA Technical Reports Server (NTRS)

A gas temperature measurement system with compensated frequency response of 1 kHz and capability to operate in the exhaust of a gas turbine engine combustor was developed. A review of available technologies which could attain this objective was done. The most promising method was identified as a two wire thermocouple, with a compensation method based on the responses of the two different diameter thermocouples to the fluctuating gas temperature field. In a detailed design of the probe, transient conduction effects were identified as significant. A compensation scheme was derived to include the effects of gas convection and wire conduction. The two wire thermocouple concept was tested in a laboratory burner exhaust to temperatures of about 3000 F and in a gas turbine engine to combustor exhaust temperatures of about 2400 F. Uncompensated and compensated waveforms and compensation spectra are presented.

Elmore, D. L.; Robinson, W. W.; Watkins, W. B.

1983-01-01

230

Global trends of measured surface air temperature  

NASA Technical Reports Server (NTRS)

The paper presents the results of surface air temperature measurements from available meteorological stations for the period of 1880-1985. It is shown that the network of meteorological stations is sufficient to yield reliable long-term, decadal, and interannual temperature changes for both the Northern Hemisphere and the Southern Hemisphere, despite the fact that most stations are located on the continents. The results indicate a global warming of about 0.5-0.7 C in the past century, with warming of similar magnitude in both hemispheres. A strong warming trend between 1965 and 1980 raised the global mean temperature in 1980 and 1981 to the highest level in the period of instrumental records. Selected graphs of the temperature change in each of the eight latitude zones are included.

Hansen, James; Lebedeff, Sergej

1987-01-01

231

Thermal expansion of blood vessels in low cryogenic temperatures Part I: A new experimental device  

PubMed Central

As part of the ongoing effort to study the mechanical behavior of biological material during cryopreservation processes, the current study focuses on thermal expansion of blood vessels at low cryogenic temperatures. The current paper (Part I) describes a new experimental device for thermal expansion measurements of blood vessels in typical conditions of vitrification, which are associated with rapid cooling rates. For validation purposes, the thermal strain of frozen arteries in the absence of cryoprotectants was measured, and found to be about 10% larger than that of polycrystalline water; this observation agrees with literature data. The companion paper (Part II) reports on experimental results of cryoprotectants permeated with VS55, DP6 and 7.05M DMSO at high cooling rates applicable to vitrification. PMID:16487503

Jimenez Rios, Jorge L.; Rabin, Yoed

2006-01-01

232

Microwave electrothermal thruster chamber temperature measurements and energy exchange calculations  

NASA Astrophysics Data System (ADS)

The microwave electrothermal thruster (MET) uses microwave frequency energy to create and sustain a resonant cavity plasma to heat a propellant. It has been operated at a variety of power levels with several propellants. The performance potential of the device has not previously been ascertained because of complex physics involved in the microwave heating, the relatively low thrust of the device, and difficulty in using conventional diagnostics to study molecular plasmas. The objectives of this investigation were to measure heavy particle temperatures and to understand gas heating processes in the MET plasma chamber for representative molecular propellants, oxygen and nitrogen. These molecules have well known thermochemical and structural properties, and they are components of liquid-storable propellants. A 2.45 GHz aluminum cylindrical thruster with converging copper alloy nozzles was used. A spectroscopic system was used to collect light emitted through a window in the plasma chamber. A Schumann-Runge emission model was developed assuming anharmonically vibrating, non-rigid rotating oxygen molecules. The commercially available LIFBASE software was used to model ionized molecular nitrogen first negative system emission from nitrogen plasmas. Experimental data were compared to models using least squared difference summation schemes. Steady and repeatable plasmas were formed with oxygen, nitrogen, and ammonia for most operating conditions. Strong coupling between fluid dynamics and plasma geometry was observed for high flow rate nitrogen tests. Oxygen temperatures of 2,000 K were measured with no variation due to spatial location or pressure and a slight increase in temperature with specific absorbed power. Nitrogen temperatures of 5,500 K were measured with no variation due to location, pressure, or specific absorbed power. Thermochemical calculations show the relationship between equilibrium enthalpy addition, temperature, dissociation fraction, and specific impulse. Nitrogen was found to be an excellent choice as a propellant component while oxygen was found to be a poor choice.

Chianese, Silvio G.

233

Temperature measurements of shocked silica aerogel foam  

NASA Astrophysics Data System (ADS)

We present recent results of equation-of-state (EOS) measurements of shocked silica (SiO2) aerogel foam at the OMEGA laser facility. Silica aerogel is an important low-density pressure standard used in many high energy density experiments, including the novel technique of shock and release. Due to its many applications, it has been a heavily studied material and has a well-known Hugoniot curve. This work then complements the velocity and pressure measurements with additional temperature data providing the full EOS information within the warm dense matter regime for the temperature interval of 1-15 eV and shock velocities between 10 and 40 km/s corresponding to shock pressures of 0.3-2 Mbar. The experimental results were compared with hydrodynamic simulations and EOS models. We found that the measured temperature was systematically lower than suggested by theoretical calculations. Simulations provide a possible explanation that the emission measured by optical pyrometry comes from a radiative precursor rather than from the shock front, which could have important implications for such measurements.

Falk, K.; McCoy, C. A.; Fryer, C. L.; Greeff, C. W.; Hungerford, A. L.; Montgomery, D. S.; Schmidt, D. W.; Sheppard, D. G.; Williams, J. R.; Boehly, T. R.; Benage, J. F.

2014-09-01

234

Impact of device geometry at different ambient temperatures on the self-heating of GaN-based HEMTs  

NASA Astrophysics Data System (ADS)

The influence of the device geometry on the self-heating for GaN-based HEMTs was assessed at different ambient temperatures, from 25 C to 175 C. The results showed that the gate width can significantly affect the heat dissipation. In addition to this, the distribution of the generated heat in the channel has been demonstrated to be dependent on the distance between the gate and drain contacts. Besides the device geometry, the ambient temperature was also found to be relevant for the thermal resistance, mainly due to the temperature-dependent thermal conductivity of the layers and the substrate. The channel temperature and the thermal resistance extracted from the measurements were in good agreement with the simulations.

Martin-Horcajo, S.; Wang, A.; Romero, M. F.; Tadjer, M. J.; Koehler, A. D.; Anderson, T. J.; Calle, F.

2014-11-01

235

21 CFR 886.4280 - Intraocular pressure measuring device.  

Code of Federal Regulations, 2011 CFR

...devices. Accessories for the device may include calibrators or recorders. The device is intended for use in the diagnosis of glaucoma. (b) Classification. Class III. (c) Date PMA or notice of completion of PDP is required. As of May 28,...

2011-04-01

236

21 CFR 886.1450 - Corneal radius measuring device.  

...Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES...limitations in 886.9, only when the device does not include computer software in the unit or topographers. [55 FR 48442,...

2014-04-01

237

21 CFR 886.4280 - Intraocular pressure measuring device.  

Code of Federal Regulations, 2010 CFR

...devices. Accessories for the device may include calibrators or recorders. The device is intended for use in the diagnosis of glaucoma. (b) Classification. Class III. (c) Date PMA or notice of completion of PDP is required. As of May 28,...

2010-04-01

238

Flow measurements in a centrifugal diffusor test device  

NASA Astrophysics Data System (ADS)

This work sought to verify concepts used in the design of a large scale, low speed, radial cascade wind tunnel which was to be used to investigate flow phenomena in and the performance of vaned radial diffusors. A major contributor to centrifugal compressor efficiency is the performance of the vaned diffusor which closely follows the impeller of the compressor. The purpose of this diffusor is to efficiently convert most of the kinetic energy of the transonic flow entering the vane into pressure. The need for an experimental facility which could simulate adequately, at low cost and in a controlled way, the environment of the centrifugal compressor motivated the development of the Centrifugal Diffusor Test Device (CDTD). It was expected that the generation of a three dimensional flow would provide improved empirical data on annular cascade performance. This measurement program surveyed the axial and circumferential uniformity of the flow at the inlet of a transonic wedge-type blading mounted in the device. Evaluation of the results showed the flow uniformity to be unsatisfactory. Leakage and other small perturbations in the flow field in the swirl generator are believed to be amplified by the basic flow configuration of the device.

Vitting, T.

1985-06-01

239

Development of a portable photosynthesis rate measurement device  

NASA Astrophysics Data System (ADS)

Photosynthesis is a very important chemical reaction in the plant, and its measurement plays critical role in the agriculture production and science research of plant. Delayed fluorescence (DF) in plants is an intrinsic label of efficiency of charge separation at P680 in photosystem II (PS II). In this paper, a portable photosynthesis rate measurement device by means of DF is proposed. It can achieve DF of plant with high sensitivity and signal-to-noise ratio basing on ultra-weak luminescence detection technique, and get photosynthesis rate by the corresponding relation between DF and photosynthesis rate. The device has its illumination power and can obtain all-weather measurement with less interference of the environment. Locale live survey can be realized by hermetic darkroom design and battery power supply. The system carries out data acquisition and processing by single-chip microcomputer control. The results show that this instrument has a lot of values such as low cost, high accuracy and good reliability and convenience.

Wang, Junsheng; Xing, Da; Xu, Wenhai

2006-09-01

240

Methods of measurement for semiconductor materials, process control, and devices  

NASA Technical Reports Server (NTRS)

The development of methods of measurement for semiconductor materials, process control, and devices is discussed. The following subjects are also presented: (1) demonstration of the high sensitivity of the infrared response technique by the identification of gold in a germanium diode, (2) verification that transient thermal response is significantly more sensitive to the presence of voids in die attachment than steady-state thermal resistance, and (3) development of equipment for determining susceptibility of transistors to hot spot formation by the current-gain technique.

Bullis, W. M. (editor)

1971-01-01

241

76 FR 81363 - Temperature-Indicating Devices; Thermally Processed Low-Acid Foods Packaged in Hermetically...  

Federal Register 2010, 2011, 2012, 2013

...foods packaged in hermetically sealed containers to allow for use of other temperature-indicating devices, in addition to mercury-in-glass thermometers, during processing. The final rule was published with one error. This document corrects that...

2011-12-28

242

EVALUATING AND TESTING EMERGENCY TESTING MONITORING DEVICES IN EXTREME COLD TEMPERATURES  

EPA Science Inventory

EPA Identifier: F8P11070 Title: Evaluating and Testing Emergency Testing Monitoring Devices in Extreme Cold Temperatures Fellow (Principal Investigator): Tyler S. O?Dell Institution: Lake Superior State University EPA GRANT Represent...

243

Low emissivity high-temperature tantalum thin film coatings for silicon devices  

E-print Network

The authors study the use of thin ( ? 230?nm) tantalum (Ta) layers on silicon (Si) as a low emissivity (high reflectivity) coating for high-temperature Si devices. Such coatings are critical to reduce parasitic radiation ...

Rinnerbauer, Veronika

244

High temperature measurement of water vapor absorption  

NASA Technical Reports Server (NTRS)

An investigation was undertaken to measure the absorption coefficient, at a wavelength of 10.6 microns, for mixtures of water vapor and a diluent gas at high temperature and pressure. The experimental concept was to create the desired conditions of temperature and pressure in a laser absorption wave, similar to that which would be created in a laser propulsion system. A simplified numerical model was developed to predict the characteristics of the absorption wave and to estimate the laser intensity threshold for initiation. A non-intrusive method for temperature measurement utilizing optical laser-beam deflection (OLD) and optical spark breakdown produced by an excimer laser, was thoroughly investigated and found suitable for the non-equilibrium conditions expected in the wave. Experiments were performed to verify the temperature measurement technique, to screen possible materials for surface initiation of the laser absorption wave and to attempt to initiate an absorption wave using the 1.5 kW carbon dioxide laser. The OLD technique was proven for air and for argon, but spark breakdown could not be produced in helium. It was not possible to initiate a laser absorption wave in mixtures of water and helium or water and argon using the 1.5 kW laser, a result which was consistent with the model prediction.

Keefer, Dennis; Lewis, J. W. L.; Eskridge, Richard

1985-01-01

245

Temperature measurement on and inside lamps  

SciTech Connect

The use of thermography within the lamp manufacturing industry can improve the quality of many types of lamps ranging from normal incandescent lamps to highly specialized lamps for sports arenas, airports or small lamps for cars. There is a strong demand for more light for the same energy input. Specialized lamps for all possible purposes are developed. But it also forces the lamp manufacturers to utilize the available materials to their extremes. The exact control of the temperatures inside or on the lamp shell has therefore become increasingly necessary as temperatures in lamps can be rather extreme. In plasma lamps for example, the plasma can have a temperature of 6,000 C, the bulk around 700 C and the electrodes inside the bulb can have temperatures in excess of 2,000 C. Thermographic methods have shown their applicability for a large number of measurement cases. Some of these methods and measurement cases are described. As these applications put very special demands on the measurement equipment, these demands are explained in more detail.

Wallin, B. [AGEMA Infrared Systems AB, Danderyd (Sweden)

1994-12-31

246

Temperature measurement on and inside lamps  

NASA Astrophysics Data System (ADS)

The use of thermography within the lamp manufacturing industry can improve the quality of many types of lamps ranging from normal incandescent lamps to highly specialized lamps for sports arenas, airports or small lamps for cars. There is a strong demand for more light for the same energy input. Specialized lamps for all possible purposes are developed. But it also forces the lamp manufacturers to utilize the available materials to their extremes. The exact control of the temperatures inside or on the lamp shell has therefore become increasingly necessary as temperatures in lamps can be rather extreme. In plasma lamps for example, the plasma can have a temperature of 6000 C, the bulb around 700 C and the electrodes inside the bulb can have temperatures in excess of 2000 C. Thermographic methods have shown their applicability for a large number of measurement cases. Some of these methods and measurement cases are described. As these applications put very special demands on the measurement equipment, these demands are explained in more detail.

Wallin, Bo

1994-03-01

247

INVESTIGATION OF A CALIBRATION DEVICE FOR THE DEPTH MEASURING SYSTEM IN ROCKWELL HARDNESS TESTING MACHINES  

Microsoft Academic Search

The paper describes investigations on the metrological properties of a newly developed calibration device for the depth measuring system in Rockwell hardness testing machines. The special feature of this calibration device is the inductive measuring system and that it is used under acting test force. The investigation of the calibration device is carried out with two different reference devices. As

Konrad Herrmann; Anton Stibler; Imre Patkovszky; Peter Strobel; Febo Menelao

2003-01-01

248

MHTGR core temperature measurement trade study  

SciTech Connect

The objective of this task was to assess the need for core non-nuclear instrumentation. The focus of this study was the evaluation of core investment risk events. Three categories of events were considered: (1) unanticipated primary loop flow leakages and core bypass flows, (2) core coolant channel flow blockages and (3) off-design core power distributions. The measurements that were considered include column average coolant exit temperatures, core average coolant exit temperature, core pressure drop and core flow rate. The findings are summarized. 3 refs., 7 figs.

Kapernick, R.; Howard, W.

1989-09-29

249

Measurement of Thin Film Integrated Passive Devices on SiC through 500 C  

NASA Technical Reports Server (NTRS)

Wireless communication in jet engines and high temperature industrial applications requires FD integrated circuits (RFICs) on wide bandgap semiconductors such as Silicon Carbide (SiC). In this paper, thin-film NiCr resistors, MIM capacitors, and spiral inductors are fabricated on a high purity semi-insulating 4H-SiC substrate. The devices are experimentally characterized through 50 GHz at temperatures of up to 500 C and the equivalent circuits are deembedded from the measured data. It is shown that the NiCr resistors are stable within 10% to 300 C while the capacitors have a value stable within 10% through 500 C.

Schwartz, Zachary D.; Ponchak, George E.; Alterovitz, Samuel A.; Downey, Alan N.; Chevalier, Christine T.

2004-01-01

250

Radiation-hardened MOS device response to high dose rate irradiations as a function of temperature  

SciTech Connect

The effect of the device temperature during irradiation at high dose rates has been investigated for transistors and ICs over the MIL-STD temperature range, -55 to 125/degree/C. At low temperatures, large increases in transistor leakage current was observed due to large shifts in the threshold voltages of parasitic field oxide transistors. The response of hardened field oxide devices and their effects on IC performance at high dose rates and low temperatures will be discussed for several different process conditions. 7 refs., 3 figs.

Sexton, F.W.; Schwank, J.R.; Kohler, R.A.

1989-01-01

251

Novel in Situ Device for Measuring Solubilities Matthew C. Gray, Alvin O. Converse, and Charles E. Wyman*  

E-print Network

Novel in Situ Device for Measuring Solubilities Matthew C. Gray, Alvin O. Converse, and Charles E by Peres and Macedo to measure the solubility of D-glucose in water and water/ethanol mixtures of the expected solubility. The cells had a thermostatically controlled water jacket to maintain temperature

California at Riverside, University of

252

Device for measuring hole elongation in a bolted joint  

NASA Technical Reports Server (NTRS)

A device to determine the operable failure mode of mechanically fastened lightweight composite joints by measuring the hole elongation of a bolted joint is disclosed. The double-lap joint test apparatus comprises a stud, a test specimen having a hole, two load transfer plates, and linear displacement measuring instruments. The test specimen is sandwiched between the two load transfer plates and clamped together with the stud. Spacer washers are placed between the test specimen and each load transfer plate to provide a known, controllable area for the determination of clamping forces around the hole of the specimen attributable to bolt torque. The spacer washers also provide a gap for the mounting of reference angles on each side of the test specimen. Under tensile loading, elongation of the hole of the test specimen causes the stud to move away from the reference angles. This displacement is measured by the voltage output of two linear displacement measuring instruments that are attached to the stud and remain in contact with the reference angles throughout the tensile loading. The present invention obviates previous problems in obtaining specimen deformation measurements by monitoring the reference angles to the test specimen and the linear displacement measuring instruments to the stud.

Wichorek, Gregory R. (inventor)

1987-01-01

253

Design of a Device for Sky Light Polarization Measurements  

PubMed Central

Sky polarization patterns can be used both as indicators of atmospheric turbidity and as a sun compass for navigation. The objective of this study is to improve the precision of sky light polarization measurements by optimal design of the device used. The central part of the system is composed of a Charge Coupled Device (CCD) camera; a fish-eye lens and a linear polarizer. Algorithms for estimating parameters of the polarized light based on three images are derived and the optimal alignments of the polarizer are analyzed. The least-squares estimation is introduced for sky light polarization pattern measurement. The polarization patterns of sky light are obtained using the designed system and they follow almost the same patterns of the single-scattering Rayleigh model. Deviations of polarization angles between observation and the theory are analyzed. The largest deviations occur near the sun and anti-sun directions. Ninety percent of the deviations are less than 5 and 40% percent of them are less than 1. The deviations decrease evidently as the degree of polarization increases. It also shows that the polarization pattern of the cloudy sky is almost identical as in the blue sky. PMID:25196003

Wang, Yujie; Hu, Xiaoping; Lian, Junxiang; Zhang, Lilian; Xian, Zhiwen; Ma, Tao

2014-01-01

254

A Device to Measure the Propulsive Power of Nematodes  

E-print Network

In the fluid dynamics video, we present a microfluidic device to measure the propulsive power of nematodes. The device consists of a tapered conduit filled with aqueous solution. The conduit is subjected to a DC electric field with the negative pole at the narrow end and to pressure-driven flow directed from the narrow end. The nematode is inserted at the conduit's wide end. Directed by the electric field (through electrotaxis), the nematode swims deliberately upstream toward the negative pole of the DC field. As the conduit narrows, the average fluid velocity and the drag force on the nematode increase. Eventually, the nematode arrives at an equilibrium position, at which its propulsive force balances the viscous drag force induced by the adverse flow. The equilibrium position of different animals, with similar body lengths, was measured as a function of the flow rate. The flow field around the nematode was obtained by direct numerical simulations with the experimentally imaged gait and the tapered geometry ...

Yuan, J; Gnatt, M; Raizen, D M; Bau, H H

2011-01-01

255

Improved Refractometer for Measuring Temperatures of Drops  

NASA Technical Reports Server (NTRS)

The Dual Rainbow refractometer is an enhanced version of the Rainbow refractometer, which is added to, and extends the capabilities of, a phase Doppler particle analyzer (PDPA). A PDPA utilizes pairs of laser beams to measure individual components of velocity and sizes of drops in a spray. The Rainbow-refractometer addition measures the temperatures of individual drops. The designs of prior versions of the Rainbow refractometer have required substantial modifications of PDPA transmitting optics, plus dedicated lasers as sources of illumination separate from, and in addition to, those needed for PDPA measurements. The enhancement embodied in the Dual Rainbow refractometer eliminates the need for a dedicated laser and confers other advantages as described below. A dedicated laser is no longer needed because the Dual Rainbow refractometer utilizes one of the pairs of laser beams already present in a PDPA. Hence, the design of the Dual Rainbow refractometer simplifies the task of upgrading PDPA hardware to enable measurement of temperature. Furthermore, in a PDPA/Dual Rainbow refractometer system, a single argon-ion laser with three main wavelengths can be used to measure the temperatures, sizes, and all three components of velocity (in contradistinction to only two components of velocity in a prior PDPA/Rainbow refractometer system). In order to enable the Dual Rainbow refractometer to utilize a pair of PDPA laser beams, it was necessary to (1) find a location for the refractometer receiver, such that the combined rainbow patterns of two laser beams amount to a pattern identical to that of a single beam, (2) adjust the polarization of the two beams to obtain the strongest rainbow pattern, and (3) find a location for the PDPA receiver to obtain a linear relationship between the measured phase shift and drop size.

Naqwi, Amir A.

2004-01-01

256

Modeling a measurement-device-independent quantum key distribution system.  

PubMed

We present a detailed description of a widely applicable mathematical model for quantum key distribution (QKD) systems implementing the measurement-device-independent (MDI) protocol. The model is tested by comparing its predictions with data taken using a proof-of-principle, time-bin qubit-based QKD system in a secure laboratory environment (i.e. in a setting in which eavesdropping can be excluded). The good agreement between the predictions and the experimental data allows the model to be used to optimize mean photon numbers per attenuated laser pulse, which are used to encode quantum bits. This in turn allows optimization of secret key rates of existing MDI-QKD systems, identification of rate-limiting components, and projection of future performance. In addition, we also performed measurements over deployed fiber, showing that our system's performance is not affected by environment-induced perturbations. PMID:24921468

Chan, P; Slater, J A; Lucio-Martinez, I; Rubenok, A; Tittel, W

2014-06-01

257

Measurements of a composite fermion split-gate device  

NASA Astrophysics Data System (ADS)

Recent theoretical and experimental work demonstrates that a two-dimensional electron gas at Landau-level filling factor ?=1/2 can be described in terms of composite fermions (CF's) for which the effective magnetic field Beff vanishes. We have measured the transport properties of CF's in a quantum point contact (QPC) defined by a wide split-gate device. Negative magnetoresistance due to suppression of backscattering in the QPC was observed both around zero magnetic field B=0 and Beff=0. We have also measured the resistance of a composite fermion QPC at Beff=0 as a function of gate voltage, with an applied magnetic field to maintain ?=1/2 in the QPC. Using a simple model to compare the results for B=0 and ?=1/2, we have determined that the channel widths for CF's are narrower than those for electrons.

Liang, C.-T.; Smith, C. G.; Mace, D. R.; Nicholls, J. T.; Frost, J. E. F.; Simmons, M. Y.; Hamilton, A. R.; Ritchie, D. A.; Pepper, M.

1996-03-01

258

Thermoreflectance temperature measurement with millimeter wave  

NASA Astrophysics Data System (ADS)

GigaHertz (GHz) thermoreflectance technique is developed to measure the transient temperature of metal and semiconductor materials located behind an opaque surface. The principle is based on the synchronous detection, using a commercial THz pyrometer, of a modulated millimeter wave (at 110 GHz) reflected by the sample hidden behind a shield layer. Measurements were performed on aluminum, copper, and silicon bulks hidden by a 5 cm thick Teflon plate. We report the first measurement of the thermoreflectance coefficient which exhibits a value 100 times higher at 2.8 mm radiation than those measured at visible wavelengths for both metallic and semiconductor materials. This giant thermoreflectance coefficient ?, close to 10-3 K-1 versus 10-5 K-1 for the visible domain, is very promising for future thermoreflectance applications.

Pradere, C.; Caumes, J.-P.; BenKhemis, S.; Pernot, G.; Palomo, E.; Dilhaire, S.; Batsale, J.-C.

2014-06-01

259

NMR measurement of bitumen at different temperatures  

NASA Astrophysics Data System (ADS)

Heavy oil (bitumen) is characterized by its high viscosity and density, which is a major obstacle to both well logging and recovery. Due to the lost information of T2 relaxation time shorter than echo spacing ( TE) and interference of water signal, estimation of heavy oil properties from NMR T2 measurements is usually problematic. In this work, a new method has been developed to overcome the echo spacing restriction of NMR spectrometer during the application to heavy oil (bitumen). A FID measurement supplemented the start of CPMG. Constrained by its initial magnetization ( M0) estimated from the FID and assuming log normal distribution for bitumen, the corrected T2 relaxation time of bitumen sample can be obtained from the interpretation of CPMG data. This new method successfully overcomes the TE restriction of the NMR spectrometer and is nearly independent on the TE applied in the measurement. This method was applied to the measurement at elevated temperatures (8-90 C). Due to the significant signal-loss within the dead time of FID, the directly extrapolated M0 of bitumen at relatively lower temperatures (<60 C) was found to be underestimated. However, resulting from the remarkably lowered viscosity, the extrapolated M0 of bitumen at over 60 C can be reasonably assumed to be the real value. In this manner, based on the extrapolation at higher temperatures (?60 C), the M0 value of bitumen at lower temperatures (<60 C) can be corrected by Curie's Law. Consequently, some important petrophysical properties of bitumen, such as hydrogen index ( HI), fluid content and viscosity were evaluated by using corrected T2.

Yang, Zheng; Hirasaki, George J.

2008-06-01

260

NMR measurement of bitumen at different temperatures.  

PubMed

Heavy oil (bitumen) is characterized by its high viscosity and density, which is a major obstacle to both well logging and recovery. Due to the lost information of T2 relaxation time shorter than echo spacing (TE) and interference of water signal, estimation of heavy oil properties from NMR T2 measurements is usually problematic. In this work, a new method has been developed to overcome the echo spacing restriction of NMR spectrometer during the application to heavy oil (bitumen). A FID measurement supplemented the start of CPMG. Constrained by its initial magnetization (M0) estimated from the FID and assuming log normal distribution for bitumen, the corrected T2 relaxation time of bitumen sample can be obtained from the interpretation of CPMG data. This new method successfully overcomes the TE restriction of the NMR spectrometer and is nearly independent on the TE applied in the measurement. This method was applied to the measurement at elevated temperatures (8-90 degrees C). Due to the significant signal-loss within the dead time of FID, the directly extrapolated M0 of bitumen at relatively lower temperatures (<60 degrees C) was found to be underestimated. However, resulting from the remarkably lowered viscosity, the extrapolated M0 of bitumen at over 60 degrees C can be reasonably assumed to be the real value. In this manner, based on the extrapolation at higher temperatures (> or = 60 degrees C), the M0 value of bitumen at lower temperatures (<60 degrees C) can be corrected by Curie's Law. Consequently, some important petrophysical properties of bitumen, such as hydrogen index (HI), fluid content and viscosity were evaluated by using corrected T2. PMID:18387325

Yang, Zheng; Hirasaki, George J

2008-06-01

261

BOOK REVIEW: Temperature Measurement, 2nd edn  

Microsoft Academic Search

This book covers a very wide range of temperature measurement apparatus and techniques including those relevant to industry, and it deals with some of the corrections that are needed in non-ideal situations. As well as dealing with all the standard instruments, e.g. thermocouples, it also deals with newer instruments, e.g. fibre optic thermometers, thermal imagers or many types of semiconductor

L. Michalski; K. Eckersdorf; J. Kucharski; J. McGhee

2002-01-01

262

Temperature measurements at an implosion focus  

Microsoft Academic Search

Spectroscopic temperature measurements are made at the focal point of imploding shock waves in the UTIAS implosion chamber, which has a hemispherical cavity 20 cm in diameter. The chamber is filled with a stoichiometric H2-O2 gas mixture at different initial pressures (1.4-6.9 MPa). The mixture is ignited at the origin by an exploding wire generating an outgoing detonation wave, which

T. Saito; I. I. Glass

1982-01-01

263

Simple uniaxial pressure device for ac-susceptibility measurements suitable for closed cycle refrigerator system  

SciTech Connect

A simple design of the uniaxial pressure device for the measurement of ac-susceptibility at low temperatures using closed cycle refrigerator system is presented for the first time. This device consists of disc micrometer, spring holder attachment, uniaxial pressure cell, and the ac-susceptibility coil wound on stycast bobbin. It can work under pressure till 0.5 GPa and at the temperature range of 30-300 K. The performance of the system at ambient pressure is tested and calibrated with standard paramagnetic salts [Gd{sub 2}O{sub 3}, Er{sub 2}O{sub 3}, and Fe(NH{sub 4}SO{sub 4}){sub 2}6H{sub 2}O], Fe{sub 3}O{sub 4}, Gd metal, Dy metal, superconductor (YBa{sub 2}Cu{sub 3}O{sub 7}), manganite (La{sub 1.85}Ba{sub 0.15}MnO{sub 3}), and spin glass material (Pr{sub 0.8}Sr{sub 0.2}MnO{sub 3}). The performance of the uniaxial pressure device is demonstrated by investigating the uniaxial pressure dependence of La{sub 1.85}Ba{sub 0.15}MnO{sub 3} single crystal with P parallel c axis. The Curie temperature (T{sub c}) decreases as a function of pressure with P parallel c axis (dT{sub c}/dP{sub parallelcaxis}=-11.65 K/GPa) up to 46 MPa. The design is simple, is user friendly, and does not require pressure calibration. Measurement can even be made on thin and small size oriented crystals. The failure of the coil is remote under uniaxial pressure. The present setup can be used as a multipurpose uniaxial pressure device for the measurement of Hall effect and thermoelectric power with a small modification in the pressure cell.

Arumugam, S.; Manivannan, N.; Murugeswari, A. [High Pressure Low Temperature Lab, School of Physics, Bharathidasan University, Tiruchirappalli 620 024 (India)

2007-06-15

264

Measurement of electrostatic potential fluctuation using heavy ion beam probe in large helical device.  

PubMed

Heavy ion beam probe (HIBP) for large helical device (LHD) has been improved to measure the potential fluctuation in high-temperature plasmas. The spatial resolution is improved to about 10 mm by controlling the focus of a probe beam. The HIBP is applied to measure the potential fluctuation in plasmas where the rotational transform is controlled by electron cyclotron current drive. The fluctuations whose frequencies change with the time constant of a few hundreds of milliseconds and that with a constant frequency are observed. The characteristics of the latter fluctuation are similar to those of the geodesic acoustic mode oscillation. The spatial profiles of the fluctuations are also obtained. PMID:19044631

Ido, Takeshi; Shimizu, Akihiro; Nishiura, Masaki; Nakano, Haruhisa; Ohshima, Shinsuke; Kato, Shinji; Hamada, Yasuji; Yoshimura, Yasuo; Kubo, Shin; Shimozuma, Takashi; Igami, Hiroe; Takahashi, Hiromi; Toi, Kazuo; Watanabe, Fumitake

2008-10-01

265

Temperature compensation techniques for resonantly enhanced sensors and devices based on optical microcoil resonators  

NASA Astrophysics Data System (ADS)

It is well known that environmental effects have a major influence on the optical stability of resonantly enhanced sensors and devices based on optical microfiber, namely in the configuration of a microcoil resonator. We propose a geometric design to reduce such effects by chirping the refractive index of successive paired turns in the microcoil resonator. The resistance to external effects such as temperature drifts can be considerably improved by optimizing the coupling coefficients and chirping profile, such that the wavelength span of the resonant condition is maximized without compensating its sensitivity to the desired measurand. We also demonstrate another technique based on resonant wavelength tuning using a compact piezoelectric ceramic disk measuring 3 mm in diameter and 1 mm in thickness, attaining tunability as high as 6.5 pm/100 V.

Chen, G. Y.; Lee, T.; Zhang, X. L.; Brambilla, G.; Newson, T. P.

2012-10-01

266

77 FR 35745 - Highway Safety Programs; Conforming Products List of Screening Devices To Measure Alcohol in...  

Federal Register 2010, 2011, 2012, 2013

...Products List of Screening Devices To Measure Alcohol in Bodily Fluids AGENCY: National Highway...Specifications for Screening Devices to Measure Alcohol in Bodily Fluids dated, March 31, 2008...Specifications for Screening Devices to Measure Alcohol in Bodily Fluids (59 FR 39382)....

2012-06-14

267

Sea Surface Temperatures (SST): Significance and Measurement  

NASA Astrophysics Data System (ADS)

Oceans cover 71 percent of Earth's surface and control the global climate. Quoted global mean temperature values and trends, largely based on land thermometers, differ substantially -" mainly because of uncertainties about SST. The ongoing controversy about the relative importance of natural climate changes and Anthropogenic Global Warming (AGW) revolves mainly around disparities between temperature trends of the atmosphere and surface (in the tropics and SH, i.e. mostly SST). Accurate measurement of SST is difficult. Geographic coverage is poor and there are many different techniques, each with its own problems and uncertainties: Water temperatures from buckets and ship-engine inlets; fixed and floating buoys; air temperatures from shipboard and island stations; and remote sensing from satellites using IR and microwaves. As is evident, each technique refers to a different level below the air-water interface. Drifter buoys (at around 50 cm) measure temperatures in the euphotic layers that are generally warmer than the bulk mixed layer sampled by ships (typically around 10 m). The IR emission arises from a 10-micron-thick skin that interacts dynamically with the underlying "mixed layer." The microwave data depend also on emissivity and therefore on surface roughness and sea state. SST data derived from corals provide some support for instrumental data but are not conclusive. The majority of corals show a warming trend since 1979; others show cooling or are ambiguous. There are different ways of interpreting this result. Physical optics dictates that the downwelling IR radiation from atmospheric greenhouse gases is absorbed in the first instance within the skin. Only direct measurements can establish how much of this energy is shared with the bulk mixed layer (to which the usual SST values refer.). SST controls evaporation and therefore global precipitation. SST influences tropical cyclones and sea-level rise; but there is lively debate on those issues. Changes in SST are also responsible for changes in deep- ocean temperatures and ocean heat storage. But recent claims that an increase in heat storage is a "smoking gun" for AGW are without merit.

Singer, S. F.

2006-05-01

268

A device for measuring sonic velocity and compressor Mach number  

NASA Technical Reports Server (NTRS)

A device has been developed which measures the velocity of sound in fluids at stagnation and is especially adaptable to turbine and compressor testing for which the constituency of the working fluid may be in doubt. By utilizing the shaft frequency of a rotary compressor, the instrument can also be used to provide a direct measurement of the compressor Mach number (ratio of blade-tip velocity to inlet velocity of sound at stagnation). A Helmholtz resonator is employed in the measurement of the sound velocity. Viscous effects in the orifice of the Helmholtz resonator are shown to be important and can be taken into account with the help of a parameter obtained from Stokes solution of the flow near an oscillating wall. This parameter includes the kinematic viscosity of the fluid and the frequency of sound in the resonator. When these effects are recognized, the resonator can be calibrated to measure velocity of sound or compressor Mach number to an accuracy of better than 0.5 percent.

Huber, Paul W; Kantrowitz, Arthur

1947-01-01

269

Device for accurately measuring mass flow of gases  

DOEpatents

A device for measuring mass flow of gases which utilizes a substantially buoyant pressure vessel suspended within a fluid/liquid in an enclosure. The pressure vessel is connected to a weighing device for continuously determining weight change of the vessel as a function of the amount of gas within the pressure vessel. In the preferred embodiment, this pressure vessel is formed from inner and outer right circular cylindrical hulls, with a volume between the hulls being vented to the atmosphere external the enclosure. The fluid/liquid, normally in the form of water typically with an added detergent, is contained within an enclosure with the fluid/liquid being at a level such that the pressure vessel is suspended beneath this level but above a bottom of the enclosure. The buoyant pressure vessel can be interconnected with selected valves to an auxiliary pressure vessel so that initial flow can be established to or from the auxiliary pressure vessel prior to flow to or from the buoyant pressure vessel.

Hylton, James O. (Clinton, TN); Remenyik, Carl J. (Knoxville, TN)

1994-01-01

270

Device for accurately measuring mass flow of gases  

DOEpatents

A device for measuring mass flow of gases which utilizes a substantially buoyant pressure vessel suspended within a fluid/liquid in an enclosure is disclosed. The pressure vessel is connected to a weighing device for continuously determining weight change of the vessel as a function of the amount of gas within the pressure vessel. In the preferred embodiment, this pressure vessel is formed from inner and outer right circular cylindrical hulls, with a volume between the hulls being vented to the atmosphere external the enclosure. The fluid/liquid, normally in the form of water typically with an added detergent, is contained within an enclosure with the fluid/liquid being at a level such that the pressure vessel is suspended beneath this level but above a bottom of the enclosure. The buoyant pressure vessel can be interconnected with selected valves to an auxiliary pressure vessel so that initial flow can be established to or from the auxiliary pressure vessel prior to flow to or from the buoyant pressure vessel. 5 figs.

Hylton, J.O.; Remenyik, C.J.

1994-08-09

271

Experimental measurement and mathematical calculation evaporator temperatures of closed loop thermosyphon  

NASA Astrophysics Data System (ADS)

The closed loop thermoshypon is device operate with working fluid phase change principle. It is a simple and reliable device providing heat transfer. This device utilizes the thermodynamic pressure difference and gravitation to circulate working fluid and has extremely high effective thermal conductivity. Usually is used to cooling of electronic components. The paper describes a design and construction of this device. As a working fluid was used fluorinert FC-72. Next the paper deal with dependences measurement of evaporator temperatures on waste heat of the electronic component and their verification by means of a mathematic calculation based on physical phenomena of boiling, condensation and heat transfer.

Nemec, Patrik; Malcho, Milan; Janda?ka, Jozef

2013-10-01

272

Use of acoustic temperature measurements in the cement manufacturing pyroprocess  

Microsoft Academic Search

Acoustic pyrometry enables accurate, reliable gas temperature measurements for use in combustion and emission control systems. This paper reviews traditional temperature measurement techniques, then focuses on two practical applications in the cement manufacturing pyroprocess that have utilized acoustic pyrometry for monitoring of gas temperatures. Progress in acoustic pyrometer technology has enabled the reliable measurement of gas temperatures, providing instantaneous temperature

George Kychakoff; Andrew F. Hollingshead; Stewart P. Boyd

2005-01-01

273

Ion Flow and Temperature Measurements in Turbulent CSDX Plasmas  

NASA Astrophysics Data System (ADS)

Experiments in the Controlled Shear Decorrelation Experiment device have shown that an azimuthally symmetric, radially sheared plasma fluid flow arises spontaneously when the primarily axial magnetic field lines terminate on insulating boundaries. Theory suggests that the shear flow is sustained by the Reynolds stress generated by collisional drift turbulence. The measurements were based on Time Delay Estimation, which cannot distinguish between ion fluid velocities and wave phase velocities, and Mach probes, which are perturbative. We present measurements of the radial profiles of ion flows and temperatures as measured with laser induced florescence in argon. The measurements were obtained with a portable, high power (> 350 W), tunable diode laser-based system operating at 668.614 nm. Mode hop free tuning of the laser over 30 GHz permitted the measurement of the entire ion velocity distribution function in a single laser frequency scan. The absolute wavelength was simultaneously recorded for each laser frequency. We will report radial profiles of ion temperature and bulk flow for both turbulent and quiescent flow regimes.

McCarren, Dustin; Scime, Earl; Thakur, Saikat; Lee, Ty; Tynan, George

2011-11-01

274

Infrared radiometric technique in temperature measurement  

NASA Technical Reports Server (NTRS)

One class of commercially available imaging infrared radiometers using cooled detectors is sensitive to radiation over the 3 to 12 micron wavelength band. Spectral filters can tailor instrument sensitivity to specific regions where the target exhibits optimum radiance. The broadband spectral response coupled with real time two-dimensional imaging and emittance/background temperature corrections make the instruments useful for remote measurement of surface temperatures from -20 C to +1500 C. Commonly used radiometric techniques and assumptions are discussed, and performance specifications for a typical modern commercial instrument are presented. The potential usefulness of an imaging infrared radiometer in space laboratories is highlighted through examples of research, nondestructive evaluation, safety, and routine maintenance applications. Future improvements in instrument design and application of the radiometric technique are discussed.

Glazer, S.; Madding, R.

1988-01-01

275

Memory-assisted measurement-device-independent quantum key distribution  

NASA Astrophysics Data System (ADS)

A protocol with the potential of beating the existing distance records for conventional quantum key distribution (QKD) systems is proposed. It borrows ideas from quantum repeaters by using memories in the middle of the link, and that of measurement-device-independent QKD, which only requires optical source equipment at the user's end. For certain memories with short access times, our scheme allows a higher repetition rate than that of quantum repeaters with single-mode memories, thereby requiring lower coherence times. By accounting for various sources of nonideality, such as memory decoherence, dark counts, misalignment errors, and background noise, as well as timing issues with memories, we develop a mathematical framework within which we can compare QKD systems with and without memories. In particular, we show that with the state-of-the-art technology for quantum memories, it is potentially possible to devise memory-assisted QKD systems that, at certain distances of practical interest, outperform current QKD implementations.

Panayi, Christiana; Razavi, Mohsen; Ma, Xiongfeng; Ltkenhaus, Norbert

2014-04-01

276

Ohmic contacts for high-temperature GaP devices  

E-print Network

at temperatures above 250 C. This thesis reports the results of a study for five n-type ohmic contacts: Au-Ge (12 wtX Ge)/Ni, Au-Sn (12 wtX Sn), Au-Sn (38 wtX Sn)/Ni, Au-Si (2 wtX Si), and Au-Te (2 wtX Te); and two p-type ohmic contacts: Au-Zn (1 wtX Zn...-Zn (1 wtX Zn) Ag-Te (1 wtX Te) Ag-Ni Ag-Te (1 wtX Te) In-Zn (1 wtX Zn) Au-Be (. 05 wtX Be) + Au Ni-Sn Au-Zn (1 wtX Zn) Au-Sn (38 wtX Sn) Ag-Zn (1 wtX Zn) + Pt Sn Au-Zn (4 wtX Zn) + Ni Sn Ni-Ge (17 wtX Ge) Ag-Te-Sb (100:1:10) Au-Ge-Ni (12...

Van der Hoeven, Willem Bernard

2012-06-07

277

Infrared Thermography Measurements of Window Thermal Test Specimen Surface Temperatures  

E-print Network

Infrared Thermography Measurements of Window Thermal Test Specimen Surface Temperatures Brent T and cold sides, respectively. Surface temperature maps were compiled using an infrared thermographic system techniques allow detailed, non-intrusive mapping of surface temperatures. Surface temperature data

278

The Display-Stereocomparator, A New Device For Biostereometric Measurements  

NASA Astrophysics Data System (ADS)

The display stereocomparator, which was primarily designed for the evaluation of stereoradiographs, is quite similar to the common stereocomparator, except that the usual point-shaped target is replaced by a complete stereoscopic image pair of a model body. The model body is superimposed to the spatial image by semi-transparent mirrors. The image pair of the model body is calculated by a computer simulation of the stereoscopic projection and is displayed on cathode ray tubes which are on-line connected to the computer. Also by computer simulation the model body can be shifted and rotated in three dimensions, and its shape and size can be altered. Motions and deformations can be continuously controlled by interactive data input with potentiometers. Thus the model can be fitted to the structures seen in the spatial image; this is equivalent to a three-dimensional measurement. The advantages of the display-stereocomparator, especially in the case of irregular bio-logic structures are discussed. Applications of the device are demonstrated for the measurement of scoliotic spines and for the fitting of implants. Furthermore the display-stereocomparator can be used in some non-stereoscopic measurements. An example of this application using monocular vision of the two images is given in the paper of B. Drerup and W. Frobin (Munster).

Hierholzer, E.

1980-07-01

279

Characterization of devices, circuits, and high-temperature superconductor transmission lines by electro-optic testing  

NASA Technical Reports Server (NTRS)

The development of a capability for testing transmission lines, devices, and circuits using the optically-based technique of electro-optics sampling was the goal of this project. Electro-optic network analysis of a high-speed device was demonstrated. The project involved research on all of the facets necessary in order to realize this result, including the discovery of the optimum electronic pulse source, development of an adequate test fixture, improvement of the electro-optic probe tip, and identification of a device which responded at high frequency but did not oscillate in the test fixture. In addition, during the process of investigating patterned high-critical-temperature superconductors, several non-contacting techniques for the determination of the transport properties of high T(sub c) films were developed and implemented. These are a transient, optical pump-probe, time-resolved reflectivity experiment, an impulsive-stimulated Raman scattering experiment, and a terahertz-beam coherent-spectroscopy experiment. The latter technique has enabled us to measure both the complex refractive index of an MgO substrate used for high-T(sub c) films and the complex conductivity of a YBa2Cu3O(7-x) sample. This information was acquired across an extremely wide frequency range: from the microwave to the submillimeter-wave regime. The experiments on the YBCO were conducted without patterning of, or contact to, the thin film. Thus, the need for the more difficult transmission-line experiments was eliminated. Progress in all of these areas was made and is documented in a number of papers. These papers may be found in the section listing the abstracts of the publications that were issued during the course of the research.

Whitaker, John F.

1991-01-01

280

Method and device for measuring emissions of gaseous substances to the atmosphere using scattered sunlight spectroscopy  

US Patent & Trademark Office Database

Methods for measuring emissions of gaseous substances to the atmosphere using scattered sunlight spectroscopy and an optical measuring device are disclosed in which the device includes a telescopic member defining a field-of-view of the optical measuring device and a scanner for controlling variation of the direction of the field of view to scan a predetermined layer of the atmosphere, the method comprising scanning the field-of-view to scan the predetermined layer of the atmosphere in the form of at least a part of a cone having its apex positioned at the optical measuring device and having a cone angle .beta.. Optical measuring devices themselves are disclosed.

2011-10-11

281

Comparison of nickel silicide and aluminium ohmic contact metallizations for low-temperature quantum transport measurements.  

PubMed

We examine nickel silicide as a viable ohmic contact metallization for low-temperature, low-magnetic-field transport measurements of atomic-scale devices in silicon. In particular, we compare a nickel silicide metallization with aluminium, a common ohmic contact for silicon devices. Nickel silicide can be formed at the low temperatures (<400C) required for maintaining atomic precision placement in donor-based devices, and it avoids the complications found with aluminium contacts which become superconducting at cryogenic measurement temperatures. Importantly, we show that the use of nickel silicide as an ohmic contact at low temperatures does not affect the thermal equilibration of carriers nor contribute to hysteresis in a magnetic field. PMID:21968083

Polley, Craig M; Clarke, Warrick R; Simmons, Michelle Y

2011-01-01

282

Effects of chamber pressure variation on the grid temperature in an inertial electrostatic confinement device  

SciTech Connect

Inertial electrostatic confinement fusion devices are compact sources of neutrons, protons, electrons, and x rays. Such sources have many applications. Improving the efficiency of the device also increases the applications of this device. Hence a thorough understanding of the operation of this device is needed. In this paper, we study the effect of chamber pressure on the temperature of the cathode. Experimentally, the grid temperature decreases as the chamber pressure increases; numerical simulations suggest that this is caused by the reduction of the hot ion current to the cathode as the pressure increases for constant power supply current. Such an understanding further supports the conclusion that the asymmetric heating of the cathode can be decreased by homogenizing the ion flow around the cathode.

Murali, S. Krupakar [Lawrenceville Plasma Physics, 128 Lincoln Blvd., Middlesex, New Jersey 08846 (United States); Emmert, G. A.; Santarius, J. F.; Kulcinski, G. L. [Fusion Technology Institute, University of Wisconsin, 1500 Engineering Drive, Madison, Wisconsin 53706 (United States)

2010-10-15

283

Fluidic packaging of microengine and microrocket devices for high-pressure and high-temperature operation  

Microsoft Academic Search

The fluidic packaging of Power MEMS devices such as the MIT microengine and microrocket requires the fabrication of hermetic seals capable of withstanding temperature in the range 20-600C and pressures in the range 100-300 atm. We describe an approach to such packaging by attaching Kovar metal tubes to a silicon device using glass seal technology. Failure due to fracture of

Yoav Peles; V. T. Srikar; Todd S. Harrison; Christopher Protz; Anna Mracek; S. Mark Spearing

2004-01-01

284

SiC Field-Effect Devices Operating at High Temperature RUBY N. GHOSH13  

E-print Network

in general and have been observed in both the 4H and 6H polytypes. Key words: SiC, metalSiC Field-Effect Devices Operating at High Temperature RUBY N. GHOSH1­3 and PETER TOBIAS2 1 State University, East Lansing, MI 48824. 3.--E-mail:ghosh@pa.msu.edu Field-effect devices based on SiC

Ghosh, Ruby N.

285

Photobleaching absorbed Rhodamine B to improve temperature measurements in PDMS microchannels  

E-print Network

. Several examples include continuous flow PCR,1 isoelectric focusing with thermally generated pH gradients field is critical for optimizing chip design and performance in such devices. Measuring fluid, the test image is normalized with a base image at a known temperature. By measuring changes

Le Roy, Robert J.

286

Temperature dependency of MOSFET device characteristics in 4H-and 6H-silicon carbide (SiC)  

E-print Network

Temperature dependency of MOSFET device characteristics in 4H- and 6H-silicon carbide (SiC) Md been used to study the device behavior in 4H-SiC at high ambient temperature. The model includes and the experimental data has been observed. 6H-SiC material system provides enhanced device performance compared to 4H-SiC

Tolbert, Leon M.

287

Sensors for soil profile water content measurement: accuracy, axial response and temperature dependence  

NASA Astrophysics Data System (ADS)

We compared sensors for soil water measurement that can be used in access tubes, including the Sentek EnviroSCAN and Diviner 2000 capacitance devices, the Delta-T PR1/6 capacitance probe, the Trime T3 tube-probe, all called electrical devices, and the soil moisture neutron probe (SMNP). Measurements were made before, during and after wetting to saturation in triplicate re-packed columns of three soils: a silty clay loam (30% clay, 53% silt), a clay (48% clay, 39% silt), and a calcic clay loam (35% clay, 40% silt) containing 50% CaCO_3. Each 75-cm deep, 55-cm diameter column was weighed continuously to 50-g precision. Conventional time domain reflectometry (TDR) measurements of water content and thermocouple measurements of temperature were made at several depths in each column. Axial sensitivity of each device was investigated by taking measurements as its probe was lowered from a height well above the soil surface to well below the soil surface. Comparisons of soil water content reported by the devices vs. soil temperature showed that all of the devices were sensitive to temperature except for TDR and the SMNP. The Trime and Delta-T devices were so sensitive to temperature (0.020 and 0.025 m^3 m-3 ^oC-1, respectively, at the wet end) as to be inappropriate for routine field measurements of soil water content. All devices exhibited measurement precision better than 0.01 m^3 m-3. Accuracy of the devices was judged by the root mean squared difference (RMSD) between mass balance column-mean water contents and those determined by the devices using factory calibrations. The Delta-T system was most inaccurate, with an RMSD of 1.30 m^3 m-3 on the wet end. At the saturated end, the Diviner, EnviroSCAN and Trime devices exhibited RMSD values >0.05 m^3 m-3, while the neutron probe and TDR exhibited RMSD <0.03 m^3 m-3. All of the devices would require separate calibrations for soil horizons with widely different properties. Of the electrical devices, only the Delta-T exhibited axial sensitivity larger than the axial height of the sensor, indicating small measurement volumes generally, and suggesting that these systems may be susceptible to soil disturbance close to the access tube during installation.

Evett, S.; Tolk, J.; Howell, T.

2003-04-01

288

Measurements of the Exerted Pressure by Pelvic Circumferential Compression Devices  

PubMed Central

Background: Data on the efficacy and safety of non-invasive Pelvic Circumferential Compression Devices (PCCDs) is limited. Tissue damage may occur if a continuous pressure on the skin exceeding 9.3 kPa is sustained for more than two or three hours. The aim of this study was to gain insight into the pressure build-up at the interface, by measuring the PCCD-induced pressure when applying pulling forces to three different PCCDs (Pelvic Binder , SAM-Sling and T-POD ) in a simplified model. Methods: The resulting exerted pressures were measured at four anatomical locations (right, left, posterior and anterior) in a model using a pressure measurement system consisting of pressure cuffs. Results: The exerted pressure varied substantially between the locations as well as between the PCCDs. Maximum pressures ranged from 18.9-23.3 kPa and from 19.2-27.5 kPa at the right location and left location, respectively. Pressures at the posterior location stayed below 18 kPa. At the anterior location pressures varied markedly between the different PCCDs. Conclusion: The circumferential compression by the different PCCDs showed high pressures measured at the four locations using a simplified model. Difference in design and functional characteristics of the PCCDs resulted in different pressure build-up at the four locations. When following the manufacturers instructions, the exerted pressure of all three PCCDs tested exceeded the tissue damaging level (9.3 kPa). In case of prolonged use in a clinical situation this might put patients at risk for developing tissue damage. PMID:20361001

Knops, Simon P; van Riel, Marcel P.J.M; Goossens, Richard H.M; van Lieshout, Esther M.M; Patka, Peter; Schipper, Inger B

2010-01-01

289

Spin-transfer switching of orthogonal spin-valve devices at cryogenic temperatures  

NASA Astrophysics Data System (ADS)

We present the quasi-static and dynamic switching characteristics of orthogonal spin-transfer devices incorporating an out-of-plane magnetized polarizing layer and an in-plane magnetized spin valve device at cryogenic temperatures. Switching at 12 K between parallel and anti-parallel spin-valve states is investigated for slowly varied current as well as for current pulses with durations as short as 200 ps. We demonstrate 100% switching probability with current pulses 0.6 ns in duration. We also present a switching probability diagram that summarizes device switching operation under a variety of pulse durations, amplitudes, and polarities.

Ye, L.; Gopman, D. B.; Rehm, L.; Backes, D.; Wolf, G.; Ohki, T.; Kirichenko, A. F.; Vernik, I. V.; Mukhanov, O. A.; Kent, A. D.

2014-05-01

290

Dynamic Mechanical Measurements of SiC for Simulations of MEMS Devices  

NASA Astrophysics Data System (ADS)

A Bohlin Rheometer fitted with a high temperature oven (-160 to 600C) and a solid-fixture device for applying torsion to a bar shaped sample was used to measure the shear modulus of polysilicon, silicon, 4H-SiC, 6H-SiC, and poly3C-SiC samples. The samples had dimensions of about 5x1x50 mm. The Young's modulus can be calculated from the measured shear modulus values. Least-squares fits have been made to the shear modulus, G', versus temperature data. From these equations the Young's modulus values at 100, 200, 300 and 400C were calculated and used as input for simulations of SiC microaccelerometers using Microcosm's Memcad software.

Wiff, D. R.

2001-03-01

291

Device and method for the measurement of depth of interaction using co-planar electrodes  

DOEpatents

A device and method for measuring a depth of interaction of an ionizing event and improving resolution of a co-planar grid sensor (CPG) are provided. A time-of-occurrence is measured using a comparator to time the leading edge of the event pulse from the non-collecting or collecting grid. A difference signal between the grid signals obtained with a differential amplifier includes a pulse with a leading edge occurring at the time-of-detection, measured with another comparator. A timing difference between comparator outputs corresponds to the depth of interaction, calculated using a processor, which in turn weights the difference grid signal to improve spectral resolution of a CPG sensor. The device, which includes channels for grid inputs, may be integrated into an Application Specific Integrated Circuit. The combination of the device and sensor is included. An improved high-resolution CPG is provided, e.g., a gamma-ray Cadmium Zinc Telluride CPG sensor operating at room temperature.

DeGeronimo, Gianluigi (Syosset, NY)

2007-09-18

292

A linear, temperature compensated, high frequency salinity measuring device  

E-print Network

miaroomgere QC meter, 4 1/2 inch, $56 ohms cor?sncntor? fee0ing n shuntea. s. . ;e&18 co3, xu)n in series 'sitb, EL QC -. ~ic; o:-, :w~. t"r -. n. "L a Suit. ~&18 . - . Ctlfler. 8" w-tie i, . )1-, c. :1 in th"= tobe 5 . . ;hich ia a, lieae of 0 ELL '. y... ". i;. I%nit Pr's!", r& o+ av&'n '. 1 ! &nI'to '9&" tQon 8?"l~3. to 1&. E 8 t&? &&. $ ', "'1'tr& tin \\Yii, t, nng gt, i a orrt'Eon trl. , "snztp?3;"&nt . =. = v&. , z'. ot;. 'o. '?. Av?F "~n'aoc4? "e &?f~N?a ~&s' eaux'e no c'a~nc&. n ILn x s...

Kelly, Minton Jones

2012-06-07

293

Measurements of charge transfer efficiency in a proton-irradiated swept charge device  

NASA Astrophysics Data System (ADS)

Charged Coupled Devices (CCDs) have been successfully used in several low energy X-ray astronomical satellites over the past two decades. Their high energy resolution and high spatial resolution make them a perfect tool for low energy astronomy, such as observing the formation of galaxy clusters and the environment around black holes. The Low Energy X-ray Telescope (LE) group is developing a Swept Charge Device (SCD) for the Hard X-ray Modulation Telescope (HXMT) satellite. A SCD is a special low energy X-ray CCD, which can be read out a thousand times faster than traditional CCDs, simultaneously keeping excellent energy resolution. A test method for measuring the charge transfer efficiency (CTE) of a prototype SCD has been set up. Studies of the charge transfer inefficiency (CTI) with a proton-irradiated SCD have been performed at a range of operating temperatures. The SCD is irradiated by 3 108cm-2 10 MeV protons.

Wang, Yu-Sa; Yang, Yan-Ji; Chen, Yong; Liu, Xiao-Yan; Cui, Wei-Wei; Xu, Yu-Peng; Li, Cheng-Kui; Li, Mao-Shun; Han, Da-Wei; Chen, Tian-Xiang; Huo, Jia; Wang, Juan; Li, Wei; Hu, Wei; Zhang, Yi; Lu, Bo; Yin, Guo-He; Zhu, Yue; Zhang, Zi-Liang

2014-06-01

294

Fabrication of spintronic devices: etching endpoint detection by resistance measurement for magnetic tunnel junctions  

NASA Astrophysics Data System (ADS)

Magnetic tunnel junctions (MTJs) have received tremendous interest since the discovery of substantial room temperature tunneling magnetoresistance (TMR) due to spin-dependent tunneling, and have been intensively investigated for applications in next-generation memory devices, hard disk drives, and magnetic sensors. In the fabrication of MTJs, etching is needed to remove the top cap layers, upper magnetic layers, and the middle oxide layer in order to form a tunneling junction. In view of this, we have devised an innovative, simple, low-cost endpoint detection method for fabricating MTJs. In this method, the endpoint is detected by measurement of the sheet resistance of the MTJ stack. Only a multimeter is needed in this method, hence it provides a simple low-cost alternative for spintronic device researchers to explore the research field of magnetic tunnel junctions. This technique is also of great use in other kinds of metallic stack etching experiments.

Pong, Philip W. T.; Schmoueli, Moshe; Egelhoff, William F., Jr.

2007-09-01

295

The understanding levels of preservice teachers of basic science concepts measurement units and devices, their misconceptions and its causes  

Microsoft Academic Search

In this study it is aimed to determine preservice science teachers and elementary teachers level of understanding about measurement units, and devices; and misconceptions about basic science concepts (mass, weight, density, heat, temperature, energy, specific heat etc.). The sample included 92 undergraduate students who are second year preservice elementary teacher; and first and second year elementary science teacher. In this

zgl Keles; Hlya Ertas; Naim Uzun; Mustafa Cansiz

2010-01-01

296

Fiber Bragg grating sensors for temperature measurement using phase retrieval  

Microsoft Academic Search

In this paper a FBG (Fiber Bragg Grating) sensor for measuring temperature and temperature distribution is presented. We have used a phase retrieval algorithm for the temperature measurement. There is presented a method for obtaining the distributed temperature distribution along a fiber Bragg grating by measuring the reflectivity spectrum. We have also a priori knowledge about the complex coupling coefficient's

Waldemar Wojcik; Piotr Kisala; Slawomir Cieszczyk

2005-01-01

297

Instrument for Measuring Temperature of Water  

NASA Technical Reports Server (NTRS)

A pseudo-Brewster-angle infrared radiometer has been proposed for use in noncontact measurement of the surface temperature of a large body of water (e.g., a lake or ocean). This radiometer could be situated on a waterborne, airborne, or spaceborne platform. The design of the pseudo-Brewster-angle radiometer would exploit the spectral-emissivity and polarization characteristics of water to minimize errors attributable to the emissivity of water and to the reflection of downwelling (e.g., Solar and cloud-reflected) infrared radiation. The relevant emissivity and polarization characteristics are the following: . The Brewster angle is the angle at which light polarized parallel to the plane of incidence on a purely dielectric material is not reflected. The pseudo-Brewster angle, defined for a lossy dielectric (somewhat electrically conductive) material, is the angle for which the reflectivity for parallel-polarized light is minimized. For pure water, the reflectivity for parallel-polarized light is only 2.2 x 10(exp -4) at its pseudo- Brewster angle of 51deg. The reflectivity remains near zero, several degrees off from the 51deg optimum, allowing this angle of incidence requirement to be easily achieved. . The wavelength range of interest for measuring water temperatures is 8 to 12 microns. The emissivity of water for parallel- polarized light at the pseudo-Brewster angle is greater than 0.999 in this wavelength range. The radiometer would be sensitive in the wavelength range of 8 to 12 microns, would be equipped with a polarizer to discriminate against infrared light polarized perpendicular to the plane of incidence, and would be aimed toward a body of water at the pseudo- Brewster angle (see figure). Because the infrared radiation entering the radiometer would be polarized parallel to the plane of incidence and because very little downwelling parallel-polarized radiation would be reflected into the radiometer on account of the pseudo-Brewster arrangement, the radiation received by the radiometer would consist almost entirely of thermal emission from the surface of the water. Because the emissivity of the water would be very close to 1, the water could be regarded as a close approximation of a blackbody for the purpose of computing its surface temperature from the radiometer measurements by use of the Planck radiation law.

Ryan, Robert; Nixon, Thomas; Pagnutti, Mary; Zanoni, Vicki

2003-01-01

298

Ion temperature and radial profile of CII-CV located in the edge and divertor plasmas of large helical device  

NASA Astrophysics Data System (ADS)

Space-resolved vacuum ultraviolet (VUV) spectroscopy using a 3-m normal incidence spectrometer is utilized to measure the impurity emission profile in the edge and divertor plasmas of the Large Helical Device (LHD). It measures the vertical profile of VUV lines emitted in the wavelength range of 300-3200 A. CII, CIII, CIV, and CV lines emitted from carbon ions are successfully measured, and their ion temperatures are derived from the Doppler broadening. Vertical profiles of the emission intensity and the ion temperature are measured simultaneously for the CIV line. The emission intensity profile, which has several peak structures, is reasonably explained by considering the relation between the C3+ ion distribution and the geometry used for the observations.

Oishi, Tetsutarou; Morita, Shigeru; Dong, Chunfeng; Goto, Motoshi; Wang, Erhui; Huang, Xianli

2014-03-01

299

Measurement of flame temperature distribution in engines by using a two-color high speed shutter TV camera system  

SciTech Connect

A two-color high speed shutter TV camera system has been developed as a new sensing device for measuring the flame temperature in engines. The TV camera system can measure the radiant intensities of high temperature substances accurately and rapidly. And, the two-dimensional temperature distribution can be easily calculated from the radiant intensities by using an image processor. This system is applicable to measurement of flame temperature in diesel and gasoline engines. The relation between the progress of combustion phenomena and the measured temperature distribution is clearly explained. It is confirmed that the system is effective for measurement of the flame temperature distribution in engines.

Kawamura, K.; Saito, A.; Yaegashi, T.; Iwashita, Y.

1989-01-01

300

STP Temperature Measurement Ideal Gas Program  

NSDL National Science Digital Library

The STP DemonIdealGas program displays a histogram of the energy of a demon that exchanges energy with an ideal gas of particles. The purpose of this simulation is to understand why the demon acts as a perfect thermometer and why its mean energy is a measure of the temperature of the gas. The default system is a one-dimensional ideal gas of N=40 particles. Additional states and parameters can be specified using the Display|Switch GUI menu item. STP DemonIdealGas is part of a suite of Open Source Physics programs that model aspects of Statistical and Thermal Physics (STP). The program is distributed as a ready-to-run (compiled) Java archive. Double-clicking the stp_DemonIdealGas.jar file will run the program if Java is installed on your computer. Additional programs can be found by searching ComPADRE for Open Source Physics, STP, or Statistical and Thermal Physics.

Gould, Harvey; Tobochnik, Jan; Christian, Wolfgang; Cox, Anne

2008-05-28

301

INNOVATIVE INSTRUMENTATION AND ANALYSIS OF THE TEMPERATURE MEASUREMENT FOR HIGH TEMPERATURE GASIFICATION  

SciTech Connect

The systematic tests of the gasifier simulator on the clean thermocouple were completed in this reporting period. Within the systematic tests on the clean thermocouple, five (5) factors were considered as the experimental parameters including air flow rate, water flow rate, fine dust particle amount, ammonia addition and high/low frequency device (electric motor). The fractional factorial design method was used in the experiment design with sixteen (16) data sets of readings. Analysis of Variances (ANOVA) was applied to the results from systematic tests. The ANOVA results show that the un-balanced motor vibration frequency did not have the significant impact on the temperature changes in the gasifier simulator. For the fine dust particles testing, the amount of fine dust particles has significant impact to the temperature measurements in the gasifier simulator. The effects of the air and water on the temperature measurements show the same results as reported in the previous report. The ammonia concentration was included as an experimental parameter for the reducing environment in this reporting period. The ammonia concentration does not seem to be a significant factor on the temperature changes. The linear regression analysis was applied to the temperature reading with five (5) factors. The accuracy of the linear regression is relatively low, which is less than 10% accuracy. Nonlinear regression was also conducted to the temperature reading with the same factors. Since the experiments were designed in two (2) levels, the nonlinear regression is not very effective with the dataset (16 readings). An extra central point test was conducted. With the data of the center point testing, the accuracy of the nonlinear regression is much better than the linear regression.

Seong W. Lee

2004-10-01

302

Quantized thermal conductance via phononic heat transport in nanoscale devices at low temperatures  

NASA Astrophysics Data System (ADS)

We study phononic heat transport in nanoscale devices. In the nonequilibrium Green's function formalism, an analytical small-frequency expansion of the phonon current transmission is derived for an arbitrary oscillator chain with typical contact-device-contact structure. Applying this expansion in a Landauer formula, it is possible to construct a systematic low-temperature expansion of the thermal conductance. It follows that quantized thermal conductance occurs as a plateau of the thermal conductance divided by the temperature within second order of the temperature expansion for completely heterogeneous systems as long as the product of force constant and oscillator mass is identical in both contacts, independent of the scattering area. Beyond this plateau, the higher-order terms of the low-temperature expansion yield a finite-temperature correction exhibiting the form of a cubic power law depending on the details of the scattering area. These findings are in agreement with experiments and numerical calculations. Our general results are applied to a double junction chain, where we find as the first phenomenon beyond our low-temperature expansion a second plateau. This plateau is associated with a thermal phase averaging of the phonon transmission, which leads for increasing temperatures to an independence of the thermal conductance from the device length.

Kso, M.; Wulf, U.

2014-04-01

303

Measurement of sound pressure via temperature fluctuations by a cold-wire microprobe at high temperatures  

NASA Astrophysics Data System (ADS)

A miniature microphone, suitable for measuring periodical pressure variations in gases at frequencies between 0.1 and 6000 Hz and temperatures up to 1200 K, has been developed in order to characterize the frequency response of gas sensors. The temperature variations in the gas due to the heat of compression are measured by a platinum cold-wire probe, from which the pressure variations are calculated. An optimized probe design makes it possible to calculate the transfer function of the microphone by a consideration of thermal boundary layers of the wire holders and surrounding walls. Both a simple approximative formula for the present setup and a more generalized finite-element calculation are presented. Thus, absolute measurements of sinusoidal pressure variations in phase and amplitude with max. 0.2 Pa resolution are possible. Comparison with a fast chemical gas sensor and internal heating measurements demonstrate the proper operation of this device. Possible disturbing effects and operation limits are discussed with respect to modified design or operating conditions in other applications for frequency response studies in physical chemistry.

Dubbe, Andreas; Gpel, Wolfgang

1993-11-01

304

Imaging photorefractive optical vibration measurement method and device  

DOEpatents

A method and apparatus are disclosed for characterizing a vibrating image of an object of interest. The method includes providing a sensing media having a detection resolution within a limited bandwidth and providing an object of interest having a vibrating medium. Two or more wavefronts are provided, with at least one of the wavefronts being modulated by interacting the one wavefront with the vibrating medium of the object of interest. The another wavefront is modulated such that the difference frequency between the one wavefront and the another wavefront is within a response range of the sensing media. The modulated one wavefront and another wavefront are combined in association with the sensing media to interfere and produce simultaneous vibration measurements that are distributed over the object so as to provide an image of the vibrating medium. The image has an output intensity that is substantially linear with small physical variations within the vibrating medium. Furthermore, the method includes detecting the image. In one implementation, the apparatus comprises a vibration spectrum analyzer having an emitter, a modulator, sensing media and a detector configured so as to realize such method. According to another implementation, the apparatus comprises a vibration imaging device.

Telschow, Kenneth L. (Idaho Falls, ID); Deason, Vance A. (Idaho Falls, ID); Hale, Thomas C. (Los Alamos, NM)

2000-01-01

305

Measurements of Beam Coupling in the Marshall Magnetic Mirror Device  

NASA Technical Reports Server (NTRS)

Experimental investigations of the coupling of an electron beam into a magnetically confined plasma have been undertaken at the Marshall Space Flight Center using the Marshall Magnetic Mirror (M3) system. The M3 system is composed of the following: two magnet coils; a cylindrical vacuum vessel; microwave source; and electron beam source. The magnet coils, which form the magnetic mirror, have an inner diameter of 25.4 cm and an outer diameter of 50.8 cm. The coils are composed of 9 coil segments with 33 turns in each segment. Each coil segment is connected in series. To create the target plasma, a 2 kW microwave source (2.45 gHz) is coupled into the vacuum chamber via waveguide. The electron beam source is a hollow cathode device created by the EPL Corporation. The hollow cathode is capable of producing a 50 amp beam with a pulse length of 1 second. It is also capable of continuous operation at 5 amps. The hollow cathode is mounted on one end of the cylindrical vacuum vessel 24 cm outside of a magnet coil. A current sensor is placed in the hollow cathode keeper bias circuit to measure emission current.

Schneider, T. A.; Vaughn, J. A.; Carruth, M. R., Jr.; Edwards, D. L.; Heard, J. W.; Whitaker, Ann F. (Technical Monitor)

2001-01-01

306

Air flow measuring device for internal combustion engines  

Microsoft Academic Search

An air\\/fuel ratio compensating device is provided for association with an internal combustion engine having a fuel control valve, air suction pipe means and pedal accelerator means , the compensating device including an area flow metal system made up of a flow detection valve positioned upstream in the air suction pipe means and operatively associated with the fuel control valve,

K. Kimata; T. Nakazeki; Y. Yasuda

1980-01-01

307

Air flow measuring device for internal combustion engines  

Microsoft Academic Search

An air\\/fuel ratio compensating device is provided for association with an internal combustion engine having a fuel control valve, air suction pipe means and pedal accelerator means, the compensating device including an area flow metal system made up of a flow detection valve positioned upstream in the air suction pipe means and operatively associated with the fuel control valve, a

K. Kimata; T. Nakazeki; Y. Yasuda

1983-01-01

308

Probabilistic Design Optimization and Reliability Assessment of High Temperature Thermoelectric Devices  

SciTech Connect

Thermoelectric (TE) devices, subcomponents of which are made of brittle materials, generate an electrical potential when they are subjected to thermal gradients through their thickness. These devices are of significant interest for high temperature environments in transportation and industrial applications where waste heat can be used to generate electricity (also referred to as "waste heat recovery" or "energy harvesting"). TE devices become more efficient as larger thermal gradients are applied across them. This is accomplished by larger temperature differences across the TE's hot and cold junctions or the use of low thermal conductivity TE materials or both. However, a TE brittle material with a combination of poor strength, low thermal conductivity, and large coefficient of thermal expansion can translate into high probability of mechanical failure (low reliability) in the presence of a thermal gradient, thereby preventing its use as intended. Therefore, the objective of this work is to demonstrate the use of an established probabilistic design methodology developed for brittle structural components and corresponding design sensitivity analyses to optimize the reliability of an arbitrary TE device. This method can be used to guide TE material and design selection for optimum reliability. The mechanical reliability of a prototypical TE device is optimized from a structural ceramic perspective, using finite element analysis and the NASA CARES/Life integrated design code. Suggested geometric redesigns and material selection are identified to enhance the reliability of the TE device.

Jadaan, Osama M. [University of Wisconsin, Platteville; Wereszczak, Andrew A [ORNL

2008-01-01

309

Boron carbon nitride materials for tribological and high temperature device applications  

NASA Astrophysics Data System (ADS)

We have used ion (or neutral) and electron cyclotron resonance assisted physical vapor deposition to produce high quality BN/CN thin films on Si and sapphire substrates. We have already demonstrated deposition of films containing a high fraction of the metastable c-BN phase as determined by FTIR spectroscopy and transmission electron microscopy (TEM). Atomic force microscopy (AFM) measurements have shown our films to have an excellent rms roughness ~10.5 (which is better than the best CVD diamond thin films). Results from frictional force microscopy (FFM) from BN and BCN films show a direct correlation with surface N content. Preliminary results show friction properties superior to that of TiN (the standard in the thin film coatings industry). Hardness measurements on the same films yielded Knoop hardness (KH) values of ~3350 kg/mm2, close to that of ceramic c-BN (3500 kg/mm2). In this paper we will present our results on the synthesis of these materials and discuss their hardness and tribological properties. Finally, BN and CN samples have been subjected to laser experiments and preliminary results are encouraging as far as the application of these materials to high temperature, high power optoelectronic systems and solid state device fabrication.

Badi, N.; Tempez, A.; Starikov, D.; Zomorrodian, V.; Medelci, N.; Bensaoula, A.; Kulik, J.; Lee, S.; Perry, S. S.; Ageev, V. P.; Garnov, S. V.; Ugarov, M. V.; Klimentov, S. M.; Tokarev, V. N.; Waters, K.; Shultz, A.

1998-01-01

310

Device Performance  

SciTech Connect

In the Device Performance group, within the National Center for Photovoltaic's Measurements and Characterization Division, we measure the performance of PV cells and modules with respect to standard reporting conditions--defined as a reference temperature (25 C), total irradiance (1000 Wm-2), and spectral irradiance distribution (IEC standard 60904-3). Typically, these are ''global'' reference conditions, but we can measure with respect to any reference set. To determine device performance, we conduct two general categories of measurements: spectral responsivity (SR) and current versus voltage (I-V). We usually perform these measurements using standard procedures, but we develop new procedures when required by new technologies. We also serve as an independent facility for verifying device performance for the entire PV community. We help the PV community solve its special measurement problems, giving advice on solar simulation, instrumentation for I-V measurements, reference cells, measurement procedures, and anomalous results. And we collaborate with researchers to analyze devices and materials.

Not Available

2006-06-01

311

Measurement and structural invariance of the antisocial process screening device.  

PubMed

Despite increasing study of psychopathic traits in children and adolescents, evidence regarding the factor structure of these traits has been inconsistent across community, clinic-referred, and incarcerated samples. Empirical support exists for both 2-factor (Impulsivity-Conduct Problems and Callous-Unemotional) and 3-factor (Narcissism, Callous-Unemotional, and Impulsivity) models, and factorial invariance across various samples has not been either tested or supported in the extant literature. We conducted confirmatory factor analyses of the Antisocial Process Screening Device (APSD; Frick & Hare, 2001) in 838 nonreferred twin pairs (M = 10.57 years, SD = 3.19 years) and 251 clinic-referred children (M = 10.82 years, SD = 3.39 years). Factorial invariance was tested across zygosity (monozygotic vs. dizygotic twins), sex (males vs. females), and age (younger vs. older children, divided by median age of 10.37 years) in the community sample and across sample type in both the community and clinic-referred samples. Results suggested that the 3-factor model fit better than did the 2-factor model in both community and clinic-referred samples. Using the best fitting 3-factor model, full measurement and structural invariance were found across zygosity, sex, and age in the community sample. Full measurement and structural invariance were also found across sample type except for differences in factor means across samples, suggesting excellent psychometric properties of the APSD. These results strongly support the robustness of the 3-factor model of psychopathic traits in children as well as the generalizability of the APSD across samples. PMID:24274050

Dong, Lu; Wu, Hao; Waldman, Irwin D

2014-06-01

312

Simultaneous directional bending and temperature measurement with overlapping long period grating and fiber Bragg grating structure  

NASA Astrophysics Data System (ADS)

A simple and compact device for simultaneous directional bending and temperature sensing is proposed and demonstrated. The device is constructed by overlapping a long period grating (LPG) on a fiber Bragg grating (FBG), and is capable of measuring the directional bending and the temperature at the same position. The LPG written with CO2 laser irradiation has a cross asymmetrical refractive modulation and the FBG is formed by UV laser exposure in the fiber core. The cross-sensitivity between measurement of the directional bending and of the temperature of an LPG is effectively eliminated by solving a matrix equation, by considering the temperature response characteristics of FBG. Experimental results show that the bending and temperature sensitivities are - 6.819 nm m-1 in a range from -2 to 2 m-1 and 10.25 pm C-1, respectively.

Wang, Li; Zhang, Weigang; Geng, Pengcheng; Gao, Shecheng; Li, Jieliang; Bai, Zhiyong; Chen, Lei; Zhang, Shanshan; Liu, Yongji; Yan, Tieyi

2014-05-01

313

Silicon-on-insulator technology for high temperature metal oxide semiconductor devices and circuits  

Microsoft Academic Search

The high temperature characteristics of devices and circuits realized in complementary metal oxide semiconductor (CMOS) technology on silicon-on-insulator (SOI) substrates are compared with other materials, and it is demonstrated that CMOS on SOI is presently the most suitable process for the realization of electronic circuits operating at up to more than 300 C.

Denis Flandre

1995-01-01

314

Tunable photonic devices based on the temperature dependent photonic band gap in chiral nematic liquid crystals  

E-print Network

Tunable photonic devices based on the temperature dependent photonic band gap in chiral nematic liquid crystals Yuhua Huang, Ying Zhou, and Shin-Tson Wu College of Optics and Photonics, University of the left-handed chiral dopant ZLI-811 mixed in a nematic liquid crystal (LC) host BL006. The solubility

Wu, Shin-Tson

315

Room temperature device performance of electrodeposited InSb nanowire field effect transistors  

E-print Network

Room temperature device performance of electrodeposited InSb nanowire field effect transistors April 2011; published online 14 June 2011 InSb nanowires have been formed by electrodeposition in porous for future nanoelectronics applications. Compared to other common semiconductors, InSb has a high room

Chen, Yong P.

316

A UV light enhanced TiO2/graphene device for oxygen sensing at room temperature  

E-print Network

temperature oxygen sensor based on TiO2/graphene device was developed with an enhanced sensing performance the oxygen gas typically use potentiometric1 and amperometric sensors.2 However, their complex structures structures and improve sensing performances. To overcome the common drawbacks of the TiO2-based oxygen sensor

Cao, Wenwu

317

Measurement Corner: Volume, Temperature and Pressure  

ERIC Educational Resources Information Center

Boyle's Law and basic relationships between volume and pressure of a gas at constant temperature are presented. Suggests two laboratory activities for demonstrating the effect of temperature on the volume of a gas or liquid. (CS)

Teates, Thomas G.

1977-01-01

318

A Conductivity Device for Measuring Sulfur Dioxide in the Air  

ERIC Educational Resources Information Center

Described is a general electroconductivity device enabling students to determine sulfur dioxide concentration in a particular location, hopefully leading to a deeper understanding of the problem of air pollution. (DF)

Craig, James C.

1972-01-01

319

Design of Temperature Measurement System Based On Intelligent Technology  

Microsoft Academic Search

The molten steel temperature is an important processing target for steel-making. Because of high temperature and strong erosion from steel and slag at present, the continuous steel temperature information can not be obtained by existing measurement method. In view of this kind of situation, this article introduces the soft measuring technique of the molten steel temperature based on the intelligent

Cheng Man; Yuan Hongbo; Shao Limin; Gao Liai

2007-01-01

320

Crowdsourcing urban air temperature measurements using smartphones  

NASA Astrophysics Data System (ADS)

Crowdsourced data from cell phone battery temperature sensors could be used to contribute to improved real-time, high-resolution air temperature estimates in urban areas, a new study shows. Temperature observations in cities are in some cases currently limited to a few weather stations, but there are millions of smartphone users in many cities. The batteries in cell phones have temperature sensors to avoid damage to the phone.

Balcerak, Ernie

2013-10-01

321

A prototype wireless inertial-sensing device for measuring toe clearance.  

PubMed

Tripping and slipping are serious health concerns for the elderly because they result in life threatening injuries i.e., fractures and high medical costs. Our recent work in detection of tripping gait patterns has demonstrated that minimum toe clearance (MTC) is a sensitive falls risk predictor. MTC measurement has previously been done in gait laboratories and on treadmills which potentially imposes controlled walking conditions. In this paper, we describe a prototype design of a wireless device for monitoring vertical toe clearance. The sensors consists of a tri-axis accelerometer and dual-axis gyroscope connected to Crossbow sensor motes for wireless data transmission. Sensor data are transmitted to a laptop and displayed on a Matlab graphic user interface (GUI). We have performed zero base and treadmill experiments to investigate sensor performance to environmental variations and compared the calculated toe clearance against measurements made by an Optotrak motion system. It was found that device outputs were approximately independent of small ambient temperature variations, had a reliable range of 20m indoors and 50m outdoors and a maximum transmission rate of 20 packets/s. Toe clearance measurements were found to follow the Optotrak measurement trend but could be improved further by dealing with double integration errors and improving data transmission rates. PMID:19163815

Lai, Daniel T H; Charry, E; Begg, R; Palaniswami, M

2008-01-01

322

Specific-heat measurement of single metallic, carbon, and ceramic fibers at very high temperature  

SciTech Connect

The main objective of this work is to present a method for measuring the specific heat of single metallic, carbon, and ceramic fibers at very high temperature. The difficulty of the measurement is due to the microscale of the fiber ({approx_equal}10 {mu}m) and the important range of temperature (700-2700 K). An experimental device, a modelization of the thermal behavior, and an analytic model have been developed. A discussion on the measurement accuracy yields a global uncertainty lower than 10%. The characterization of a tungsten filament with thermal properties identical to those of the bulk allows the validation of the device and the thermal estimation method. Finally, measurements on carbon and ceramic fibers have been done at very high temperature.

Pradere, C.; Goyheneche, J.M.; Batsale, J.C.; Dilhaire, S.; Pailler, R. [TREFLE, UMR 8508, Esplanade des Arts et Metiers, 33405 Talence (France) and LCTS, UMR 5801, 3 allee de La Boetie, 33600 Pessac (France); LCTS, UMR 5801, 3 allee de La Boetie, 33600 Pessac (France); TREFLE, UMR 8508, Esplanade des Arts et Metiers, 33405 Talence (France); CPMOH, UMR 5798, 351 cours de la Liberation, 33405 Talence (France); LCTS, UMR 5801, 3 allee de La Boetie, 33600 Pessac (France)

2005-06-15

323

Development and evaluation of measurement devices used to support testing of radioactive material transportation packages  

Microsoft Academic Search

Radioactive material package designers use structural testing to verify and demonstrate package performance. A major part of evaluating structural response is the collection of instrumentation measurement data. Sandia National Laboratories (SNL) has an ongoing program to develop and evaluate measurement devices to support testing of radioactive material packages. Measurement devices developed in support of this activity include evaluation channels, ruggedly

W. L. Uncapher; D. J. Ammerman; D. R. Stenberg; D. R. Bronowski; M. Arviso

1992-01-01

324

Soil moisture inferences from thermal infrared measurements of vegetation temperatures  

NASA Technical Reports Server (NTRS)

Thermal infrared measurements of wheat (Triticum durum) canopy temperatures were used in a crop water stress index to infer root zone soil moisture. Results indicated that one time plant temperature measurement cannot produce precise estimates of root zone soil moisture due to complicating plant factors. Plant temperature measurements do yield useful qualitative information concerning soil moisture and plant condition.

Jackson, R. D. (principal investigator)

1981-01-01

325

Infrared transtympanic temperature measurement and otitis media with effusion  

Microsoft Academic Search

Body temperature is an important clinical measurement. It can be estimated by sublingual, rectal, axillary or skin measurement. Pulmonary artery temperature measurement is the gold standard in the research setting, but is obviously inapplicable for routine clinical use. Infrared estimation of core temperature at the tympanic membrane has been proposed as an effective and accurate method. We investigate whether the

P. J. Robb; R. Shahab

2001-01-01

326

Metallic Contaminant Detection using a High-Temperature Superconducting Quantum Interference Devices Gradiometer  

NASA Astrophysics Data System (ADS)

We develop magnetic metallic contaminant detectors using high-temperature superconducting quantum interference devices (HTS-SQUIDs) for industrial products. Finding ultra-small metallic contaminants is an important issue for manufacturers producing commercial products such as lithium ion batteries. If such contaminants cause damages, the manufacturer of the product suffers a big financial loss due to having to recall the faulty products. Previously, we described a system for finding such ultra-small particles in food. In this study, we describe further developments of the system, for the reduction of the effect of the remnant field of the products, and we test the parallel magnetization of the products to generate the remnant field only at both ends of the products. In addition, we use an SQUID gradiometer in place of the magnetometer to reduce the edge effect by measuring the magnetic field gradient. We test the performances of the system and find that tiny iron particles as small as 50 50 ?m2 on the electrode of a lithium ion battery could be clearly detected. This detection level is difficult to achieve when using other methods.

Saburo, Tanaka; Tomohiro, Akai; Makoto, Takemoto; Yoshimi, Hatsukade; Takeyoshi, Ohtani; Yoshio, Ikeda; Shuichi, Suzuki

2010-08-01

327

Junction temperature measurements and reliability of GaN FETs  

NASA Astrophysics Data System (ADS)

AlGaN/GaN field effect transistors (FETs) have shown tremendous advances in performance and reliability over recent years. They are unique in that they operate under the presence of a high density of defects, imperfect surfaces and interfaces. We review key challenges related to defects in these transistors, and recent novel characterization techniques and approaches to study the impact of these imperfections on the device thermal characteristics and reliability, as basis for developing devices with an increased safe operating area (SOA). This includes the development of a nanometer resolution junction temperature analysis using SiC solid immersion lenses, results on hot electron effects and on the role of dislocations and point defects for device reliability. In addition techniques such as dynamic transconductance to access traps near the channel are presented. The approaches shown take advantage of the complementary nature of electrical, optical and microstructural device analysis, combined with thermal and electrical device simulations.

Kuball, Martin; Pomeroy, James W.; Montes Bajo, Miguel; Silvestri, Marco; Uren, Michael J.; Killat, Nicole

2013-03-01

328

Receiver protecting device based on microstrip structure with high-temperature superconductor film  

NASA Astrophysics Data System (ADS)

New design of an effective device for protection against high-power electromagnetic pulses has been created based on a pair of noninteracting microstrip resonators, which are coupled in the working frequency band via a third resonator based on a thin film of high-temperature superconductor (HTSC) occurring in the superconducting state. Under the action of an electromagnetic pulse with the power above a certain threshold, the HTSC film element passes from the superconducting to normal (high-resistivity) state, thus breaking the coupling between resonators. This leads to power limitation at the device output due to a strong signal reflection from the input.

Belyaev, B. A.; Govorun, I. V.; Leksikov, A. A.; Serzhantov, A. M.

2012-03-01

329

Temperature sensitivity of capillary-driven flow: application to age monitoring devices.  

PubMed

The effects of time-dependent temperature fluctuations on surface-tension driven fluid flow inside a capillary are modeled using classical hydrodynamics. To begin, Newton's second law is evoked to derive a nondimensional equation of motion that describes the time-evolution of the fluid front position and velocity as a function of system geometry, fluid properties, and fluid temperature. This model is used to examine how temperature excursions affect the instantaneous and long-term position and velocity of the fluid front inside the capillary. Next, the effects of orientation on the movement of high viscosity fluids through a capillary are examined. From these findings, a procedure is developed for designing non-powered time-temperature integration devices for recording the cumulative temperature exposure history of an environment. PMID:22300654

Thomas, J A; Boyle, M P; Hunter, L W; Tiffany, J E

2012-04-15

330

Air temperature profile and air/sea temperature difference measurements by infrared and microwave scanning radiometers  

E-print Network

Air temperature profile and air/sea temperature difference measurements by infrared and microwave air temperature profile and air/sea temperature difference. The main advantage of this technique measurements, accounting for air attenuation and sea surface roughness. Then we show retrieval results

Shaw, Joseph A.

331

Sea surface temperature measurements with AIRS  

NASA Technical Reports Server (NTRS)

The comparison of global sea surface skin temperature derived from cloud-free AIRS super window channel at 2616 cm-1 (sst2616) with the Real-Time Global Sea Surface Temperature for September 2002 shows surprisingly small standard deviation of 0.44K.

Aumann, H.

2003-01-01

332

A spectroscopic temperature measurement of converging detonations  

Microsoft Academic Search

Several experimental investigations are reported on converging gaseous detonations with a view toward obtaining a high-temperature plasma and ensuring application to a high-power gasdynamic laser. A microdensitometer is used to analyze the CN violet emission band from the converging point. A method of matching the entire emission spectra is used to determine the temperature at the converging point of a

T. Sugimura; T. Fujiwara

1980-01-01

333

Global trends of measured surface air temperature  

Microsoft Academic Search

We analyze surface air temperature data from available meteorological stations with principal focus on the period 1880-1985. The temperature changes at mid- and high latitude stations separated by less than 1000 km are shown to be highly correlated; at low latitudes the correlation falls off more rapidly with distance for nearby stations. We combine the station data in a way

James Hansen; Sergej Lebedeff

1987-01-01

334

MELIFT - A new device for accurate measurements in a snow rich environment  

NASA Astrophysics Data System (ADS)

A deep snow pack, remote locations, no external power supply and very low temperatures are often the main ingredients when it comes to the deployment of meteorological stations in mountainous terrain. The accurate position of the sensor related to the snow surface is normally not known. A new device called METLIFT overcomes the problems. WMO recommends a height between 1.2 m and 2 m above ground level for the measurement of air temperature and humidity. The height above ground level is specified to take care of the possible strong vertical temperature and humidity gradients at the lowest layers in the atmosphere. Especially in snow rich and remote locations it may be hardly possible to follow this advice. Therefore most of the meteorological stations in mountainous terrain are situated at mountain tops where strong winds will blow off the snow or in valleys where a daily inspection of the sensors is possible. In other unpopulated mountainous areas, e.g. basins, plateaus, the distance of the sensor to the snow surface is not known or the sensor will be snow-covered. A new device was developed to guarantee the sensor height above surface within the WMO limits in harsh and remote environments. An ultrasonic snow height sensor measures the distance to the snow surface. If it exceeds certain limits due to snow accumulation or snow melt the lift adapts its height accordingly. The prototype of METLIFT has been installed in Lower Austria at an altitude of 1000m. The lift is 6 m high and can pull out for another 4 m. Sensor arms are mounted every meter to allow the connection of additional sensors or to measure a profile of a certain parameter of the lowest 5 m above surface. Sensors can be added easily since cable wiring is provided to each sensor arm. Horizontal winds are measured at 7 m height above surface. METLIFT is independent of external power supply. Three lead gel accumulators recharged by three solar panels provide the energy necessary for the sensors, the data loggers, the data transmission components and for the electromotor to lift the system. METLIFT is energy optimised to keep the energy consumption at low levels. The components of the lift device consist of a 12V electromotor with a worm gear with a transmission rate of 2856:1. This means that the lift moves extremely slow. The data logger can be programmed via the GSM connection from remote locations, the data flow is also conducted via this connection. First results of the winter campaign 2011/2012 will be presented at the conference.

Dorninger, M.

2012-04-01

335

Integration of High Dose Boron Implants--Modification of Device Parametrics through Implant Temperature Control  

SciTech Connect

In the present study, we have extended a previously reported 250 nm logic p-S/D implant (7 keV B 4.5x10{sup 15} cm{sup -2}) process matching exercise [5] to include wafer temperature, and demonstrate that matching can be obtained by increasing the temperature of the wafer during implant. We found that the high dose rate delivered by the single wafer implanter caused the formation of a clear amorphous layer, which upon subsequent annealing altered the diffusion, activation, and clustering properties of the boron. Furthermore, increasing the temperature of the wafer during the implant was sufficient to suppress amorphization, allowing profiles and device parameters to become matched. Figure 5 shows a representative set of curves indicating the cluster phenomena observed for the lower temperature, high flux single wafer implanter, and the influence of wafer temperature on the profiles. The results indicate the strong primary effect of dose rate in determining final electrical properties of devices, and successful implementation of damage engineering using wafer temperature control.

Schmeide, Matthias [Infineon Technologies Dresden GmbH, Koenigsbruecker Str. 180, D-01099 Dresden (Germany); Ameen, M. S.; Kondratenko, Serguei; Krimbacher, Bernhard; Reece, Ronald N. [Axcelis Technologies, Inc., 108 Cherry Hill Dr., Beverly, MA, 01915 (United States)

2011-01-07

336

Effect of an ultrasonic device on temperatures generated in bone and on bone-cement structure.  

PubMed

Cement removal during revision arthroplasty can be a tedious, time-consuming process. The usual methods of removing cement include high-speed drills, chisels, saws and reamers, which are often associated with fracture and/or perforation of the femoral shaft. Ultrasound has been used in dentistry to remove plaque and in ophthalmology to remove cataracts and is now applied to cement removal in orthopaedic surgery. There is little data available on the effect of ultrasound on temperatures generated in bone and on its effects on the structure of bone-cement. A cement mantle was constructed in the intramedullary canal in each of six 10 cm lengths of human cadaver femora. A temperature probe was then inserted into predrilled holes and temperatures generated by the ultrasonic device were recorded under a variety of conditions. In addition, a cement cylinder was microscopically evaluated after an ultrasonic tool had been inserted. Temperatures generated by the ultrasonic tool in cadaver bone were no higher than previously reported temperatures of 140 degrees C generated by high-speed drills. Furthermore, temperatures at the bone-cement interface never exceeded 60 degrees C when saline irrigation was used in conjunction with the ultrasonic tools, and were below 40 degrees C 1 minute after deactivation of the device. Microscopic examination shows that ultrasound produced local changes in the structure of bone-cement converting it from a microscopically spherical interlocked material to one that appears homogeneous and granular. PMID:8409994

Brooks, A T; Nelson, C L; Stewart, C L; Skinner, R A; Siems, M L

1993-08-01

337

A novel measurement procedure for the Specific Absorption Rate conformity assessment of WiFi devices  

Microsoft Academic Search

The specific absorption rate (SAR) conformity assessment of WiFi devices is herein investigated. In order to derive the time-average of the SAR, a common approach is to evaluate an ensemble average of the measured samples. This approach cannot be applied when measuring non-deterministic signals typically transmitted by WiFi devices. The signal transmitted between WiFi devices during data exchange is complex

Vikass Monebhurrun; Thierry Letertre

2009-01-01

338

Titan's Surface Temperatures Measured by Cassini CIRS  

NASA Technical Reports Server (NTRS)

A large fraction of 19-micron thermal radiation from the surface of Titan reaches space through a spectral window of low atmospheric opacity. The emergent radiance, after removing the effect of the atmosphere, gives the brightness temperature of the surface. This atmospheric window is covered by the far-infrared channel of the Composite Infrared spectrometer1 (CIRS) on Cassini. In mapping Titan surface temperatures, CIRS is able to improve upon results of Voyager IRIS, by taking advantage of improved latitude coverage and a much larger dataset. Observations are from a wide range of emission angles and thereby provide constraints on the atmospheric opacity and radiance that are used to derive the surface temperature. CIRS finds an average equatorial surface brightness temperature of 93.7+/-0.6 K, virtually identical to the HASI temperature at the Huygens landing site. Mapping in latitude shows that the surface temperature decreases toward the poles by about 2 K in the south and 3 K in the north. This surface temperature distribution is consistent with the formation of lakes seen at high latitudes on Titan.

Jennings, Donald E.; Flasar, F. M.; Kundle, V. G.; Samuelson, R. E.; Pearl, J. C.; Nixon, C. A.; Carlson, R. C.; Mamoutkine, A. A.; Brasunas, J. C.; Guandique, E.; Arhterberg, R. K.; Bjoraker, G. L.; Romani, P. N.; Segura, M. E.; Albright, S. A.; Elliott, M. H.; Tingley, J. S.; Calcutt, S.; Coustenis, A.; Bezard, B.; Courtin, R.

2008-01-01

339

Orthogonal optimization for room temperature magnetron sputtering of ZnO:Al films for all-solid electrochromic devices  

NASA Astrophysics Data System (ADS)

In order to obtain competent and quality (high transparency, conductivity and stability) aluminium-doped zinc oxide (ZnO:Al, ZAO) films for all solid electrochromic devices, ZAO films were prepared by direct current (D.C.) reactive magnetron sputtering at room temperature based on orthogonal design. Optical and electrical property dependences of the films on the four dominant sputtering parameters: sputtering time, target-substrate distance, sputtering power and O2 flow ratio were simultaneously investigated with measured results using mathematical and statistical method. Optimal Parameters to fabricate ZAO films with optimum comprehensive performances were obtained ultimately. Resistivity and carrier concentration of ZAO film deposited with optimized parameters were 3.89 10-4 ? cm and 1.09 1021 cm-3, respectively. ZAO films with these superior properties were employed as transparent electrodes eventually in a WO3 based all-solid electrochromic device which displayed good electrochromic performance. The regulation range for transmittance in the visible region of the device was more than 50%, which was comparable to that of the device adopting indium tin oxide (ITO) films as electrodes.

Wang, Tao; Diao, Xungang; Ding, Peng

2011-02-01

340

Research on some influence factors in high temperature measurement of metal with thermal infrared imager  

NASA Astrophysics Data System (ADS)

Thermal infrared imagers have been introduced into the research field of metal processing temperature in recent years, such as the workpiece's and the tool's temperatures in metal machining. However, these metal components are usually non-black body with unknown and varied surface emissivities, plus the in-line processing environment also effects the measurement of infrared imager. Hereby, accurately measuring metal processing temperature with infrared imager becomes a challenge. In this paper, the temperature measurement formula of infrared imager is analyzed first, and next the experimental devices designed by the authors is introduced, then several influences on the temperature measurement, such as low temperature and high temperature backgrounds with high emissivity, object area / viewing field ratio, and the shooting angel, are experimentally investigated with a thermal infrared imager. The results indicate that a low temperature background with high emissivity and a small object area / viewing field ratio, as well as a shooting direction perpendicular to the measured surface, can improve the measurement accuracy. This work provides a useful reference for the temperature measurement in metal processing.

Yanming, QUAN; Hao, XU; Zhiyong, KE

341

A probe for the measurement of electrical unbalance of networks and devices  

Microsoft Academic Search

A probe has been developed to measure residual electrical unbalance of nominally balanced networks and devices. In the form described, it makes convenient the use of single-ended 50 ? instruments to measure electrical unbalance of wire pair networks and two-terminal devices. For electromagnetic compatibility (EMC) planning purposes, a knowledge of the electrical unbalance at signal interfaces in wire pair networks

Ian P. Macfarlane

1999-01-01

342

Influence and modification of coupling device on low voltage power network channel characterization measurement  

Microsoft Academic Search

Channel characterization measurements of power line are often carried out when the power system is operation actively. So the coupling device is adopted to isolate the power frequency signal. Due to the impedance mismatch between the output of coupling device and power network, the energy of carrier signal will be attenuated, which causes much influence on the accuracy of measurement

Zheng Tao; Yang Xiaoxian; Zhang Baohui

2005-01-01

343

Measuring Device of Hob Helix Error Based on Single Chip Microcomputer  

Microsoft Academic Search

Device of measuring hob helix error based on single chip microcomputer is introduced. This kind of measuring device collects the displacement signal through the inductance sensor. The single chip microcomputer system gathers data, processes data, and displays the result by LED. This system can also communicate with computer in order to help testers to analysis the error curve.

Xiaolan Fan; Na Deng

2011-01-01

344

30 CFR 75.320 - Air quality detectors and measurement devices.  

...2014-07-01 2014-07-01 false Air quality detectors and measurement devices. 75.320 Section 75.320 Mineral Resources...MINES Ventilation 75.320 Air quality detectors and measurement devices. (a) Tests for methane shall be made...

2014-07-01

345

Turbine Blade Temperature Measurements Using Thin Film Temperature Sensors  

NASA Technical Reports Server (NTRS)

The development of thin film temperature sensors is discussed. The technology for sputtering 2 micron thin film platinum versus platinum 10 percent rhodium thermocouples on alumina forming coatings was improved and extended to applications on actual turbine blades. Good adherence was found to depend upon achieving a proper morphology of the alumina surface. Problems of adapting fabrication procedures to turbine blades were uncovered, and improvements were recommended. Testing at 1250 K at one atmosphere pressure was then extended to a higher Mach No. (0.5) in combustor flow for 60 hours and 71 thermal cycles. The mean time to failure was 47 hours accumulated during 1 hour exposures in the combustor. Calibration drift was about 0.1 percent per hour, attributable to oxidation of the rhodium in the thin films. An increase in film thickness and application of a protective overcoat are recommended to reduce drift in actual engine testing.

Grant, H. P.; Przybyszewski, J. S.; Claing, R. G.

1981-01-01

346

Optical diagnostics for soot and temperature measurement in diesel engines  

Microsoft Academic Search

This paper reviews the optical techniques for in-cylinder combustion temperature measurement, particularly soot measurements in diesel engines. The review starts with the two-colour method for in-cylinder soot and combustion temperature measurement. The principle and implementation of the two-colour technique are described in detail. Both signal point and full-field temperature and soot measurements by the two-colour method are considered. In the

H. Zhao; N. Ladommatos

1998-01-01

347

Application of digital holography in temperature distribution measurement  

NASA Astrophysics Data System (ADS)

A reflection heat source including a radiator as well as an aluminum plate is designed, and the temperature field of the aluminum plate is used as the tested object. The reflection lensless Fourier transform (LFT) digital holography is performed to measure the temperature field distribution. For the comparison, the temperature measurement system within the radiator is used to measure the temperature distributions. The results obtained by these two methods are in good agreement, which demonstrates that the digital holography method is valid for the measurement of the temperature distribution.

Wang, Guangjun; Li, Yan; Wang, Dayong; Zhao, Jie

2010-11-01

348

Application of low-temperature substrate bonding in fabrication of reusable micro-fluidic devices  

Microsoft Academic Search

The plasma polymerised (PP) films were deposited on silicon substrates and used to bond the substrates at a low temperature (130C). Different types of monomers were used to deposit PP films on ?-electrode and ?-channel of micro-fluidic devices (MFD) to tailor the surface properties. To confirm the PP film deposition on the substrates the surface chemistry was characterized using X-ray

Marshal Dhayal

2006-01-01

349

CARBON NANOTUBE ARRAY THERMAL INTERFACES FOR HIGH-TEMPERATURE SILICON CARBIDE DEVICES  

E-print Network

synthesized from templated Fe2O3 nanoparticles on the C-face of 4H-SiC substrates by microwave plasma chemical, the bandgap of 4H-SiC (the most attractive SiC polytype for electronic devices) is 3.23 eV [5], compared vapor deposition (MPCVD), and the room-temperature thermal resistances of SiC-MWCNT-Ag interfaces at 69

Xu, Xianfan

350

A low-temperature sample orienting device for single crystal spectroscopy at the SNS  

Microsoft Academic Search

A low temperature sample orientation device providing three axes of rotation has been successfully built and is in testing for use on several spectrometers at the spallation neutron source (SNS). Sample rotation about the vertical (omega) axis of nearly 360 and out of plane tilts (phi and v) of from -3.4 to 4.4 and from -2.8 to 3.5, respectively, are

T. E. Sherline; L. Solomon; C. K. Roberts Ii; D. Bruce; B. Gaulin; G. E. Granroth

2010-01-01

351

Scanning infrared radiometer for measuring the airsea temperature difference  

E-print Network

when the air­sea temperature difference is negative, and Hwang and Shemdin3 showed that sea-surfaceScanning infrared radiometer for measuring the air­sea temperature difference Joseph A. Shaw a vertically scanning infrared radiometer for measuring the air­sea temperature difference without disturbing

Shaw, Joseph A.

352

TEMPERATURE MEASUREMENT SYSTEM OF NOVOSIBIRSK FREE ELECTRON LASER  

E-print Network

is actually equal to the temperature of the surface this sensor is connected to, the temperature couldTEMPERATURE MEASUREMENT SYSTEM OF NOVOSIBIRSK FREE ELECTRON LASER B.A.Gudkov, P.A.Selivanov, V describes the temperature-monitoring system of Novosibirsk FEL. The main task of this system is to prevent

Kozak, Victor R.

353

Novel devices for solvent delivery and temperature programming designed for capillary liquid chromatography.  

PubMed

Analyses in chromatographic systems able to save mobile and stationary phases without reducing efficiency and resolution are of current interest. These advantages regarding savings have challenged us to develop a system dedicated to miniaturized liquid chromatography. This paper reports on the development of a high-pressure syringe-type pump, an oven able to perform isothermal and temperature programming and a software program to control these chromatographic devices. The experimental results show that the miniaturized system can generate reproducible and accurate temperature and flow rate. The system was applied to the separation of statins and tetracylines and showed excellent performance. PMID:24838528

Coutinho, Lincoln Figueira Marins; Nazario, Carlos Eduardo Domingues; Monteiro, Alessandra Maffei; Lanas, Fernando Mauro

2014-08-01

354

Effects of nuclear radiation and elevated temperature storage on electroexplosive devices  

NASA Technical Reports Server (NTRS)

Aerospace type electroexplosive devices (EEDs) were subjected to nuclear radiation. Components and chemicals used in the EEDs were also included. The kind of radiation and total dosage administered were those which may be experienced in a space flight of 10 years duration, based on information available at this time. After irradiation, the items were stored in elevated constant-temperature ovens to accelerate early effects of the exposure to radiation. Periodically, samples were withdrawn for visual observation and testing. Significant changes occurred which were attributed to elevated-temperature storage and not radiation.

Menichelli, V. J.

1976-01-01

355

A low-temperature crystallization path for device-quality ferroelectric films  

SciTech Connect

We show a path for low-temperature crystallization of device-quality solution-processed lead zirconate titanate films. The essential aspect of the path is to circumvent pyrochlore formation at around 300 deg. C during temperature increase up to 400 deg. C. By maintaining enough carbon via pyrolysis at 210 deg. C, well below the temperature for pyrochlore formation, Pb{sup 2+} can be reduced to Pb{sup 0}. This leads to the lack of Pb{sup 2+} in the film to suppress the development of pyrochlore, which accounts for the usual high-temperature conversion to perovskite. Films on metal, metal/oxide hybrid, and oxide bottom electrodes were successfully crystallized at 400-450 deg. C.

Li Jinwang; Trinh, Bui Nguyen Quoc; Miyasako, Takaaki; Mitani, Tadaoki [Japan Science and Technology Agency (JST), ERATO, Shimoda Nano-Liquid Process Project, 2-5-3 Asahidai, Nomi, Ishikawa 923-1211 (Japan); Kameda, Hiroyuki [Japan Science and Technology Agency (JST), ERATO, Shimoda Nano-Liquid Process Project, 2-5-3 Asahidai, Nomi, Ishikawa 923-1211 (Japan); Electronic Materials Development Laboratory, ADEKA Corporation, 7-2-34 Higashi-ogu, Arakawa-ku, Tokyo 116-8554 (Japan); Tue, Phan Trong [School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa 923-1292 (Japan); Tokumitsu, Eisuke [Japan Science and Technology Agency (JST), ERATO, Shimoda Nano-Liquid Process Project, 2-5-3 Asahidai, Nomi, Ishikawa 923-1211 (Japan); Precision and Intelligence Laboratory, Tokyo Institute of Technology, 4259-R2-19 Nagatsuta, Midori-ku, Yokohama 226-8503 (Japan); Shimoda, Tatsuya [Japan Science and Technology Agency (JST), ERATO, Shimoda Nano-Liquid Process Project, 2-5-3 Asahidai, Nomi, Ishikawa 923-1211 (Japan); School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa 923-1292 (Japan)

2010-09-06

356

Improvised explosive device (IED) counter-measures in Iraq  

Microsoft Academic Search

Summary form only given: Land mines have been used in warfare since the 13l century. Their greatest weakness has always been to coordinate the timing of the explosion with an enemy's movement. improvised explosive devices (IED's) are mines that are constructed in the field using available munitions. In the 16th century these were detonated using a clock-timer or concealed trip-wire.

J. Ziegler

2009-01-01

357

An intelligent instrument for measuring exhaust temperature of marine engine  

NASA Astrophysics Data System (ADS)

Exhaust temperature of the marine engine is commonly measured through thermocouple. Measure deviation will occur after using the thermocouple for some time due to nonlinearity of thermocouple itself, high temperature and chemical corrosion of measure point. Frequent replacement of thermocouple will increase the operating cost. This paper designs a new intelligent instrument for solving the above-mentioned problems of the marine engine temperature measurement, which combines the conventional thermocouple temperature measurement technology and SCM(single chip microcomputer). The reading of the thermocouple is simple and precise and the calibration can be made automatically and manually.

Ma, Nan-Qi; Su, Hua; Liu, Jun

2006-12-01

358

Current Sensing Noise Thermometry: A fast practical solution to low temperature measurement  

E-print Network

We describe the design and performance of a series of fast, precise current sensing noise thermometers. The thermometers have been fabricated with a range of resistances from 1.290 $\\Omega$ down to 0.2 m$\\mathrm{\\Omega}$. Resulting in either a thermometer that has been optimised for speed, taking advantage of the improvements in superconducting quantum interference device (SQUID) noise and bandwidth, or a thermometer optimised for ultra-low temperature measurement, minimising the system noise temperature. By using a single temperature calibration point, we show that noise thermometers can be used for accurate measurements over a wide range of temperatures below 4~K. Comparisons with a melting curve thermometer, a calibrated germanium thermometer and a pulsed platinum nuclear magnetic resonance thermometer are presented. For the 1.290 $\\mathrm{\\Omega}$ resistance we measure a 1 % precision in just 100 ms, and have shown this to be independent of temperature.

Casey, Andrew; Levitin, Lev V; Lusher, Chris P; Saunders, John; Shibahara, Aya; van der Vliet, Harriet; Drung, Dietmar; Schurig, Thomas; Batey, Graham; Cuthbert, Michael; Matthews, Anthony

2013-01-01

359

Current Sensing Noise Thermometry: A Fast Practical Solution to Low Temperature Measurement  

NASA Astrophysics Data System (ADS)

We describe the design and performance of a series of fast, precise current sensing noise thermometers. The thermometers have been fabricated with a range of resistances from 1.290 down to 0.2 m. This results in either a thermometer that has been optimised for speed, taking advantage of the improvements in superconducting quantum interference device noise and bandwidth, or a thermometer optimised for ultra-low temperature measurement, minimising the system noise temperature. With a single temperature calibration point, we show that noise thermometers can be used for accurate measurements over a wide range of temperatures below 4 K. Comparisons with a melting curve thermometer, a calibrated germanium thermometer and a pulsed platinum nuclear magnetic resonance thermometer are presented. For the 1.290 resistance we measure a 1 % precision in just 100 ms, and have shown this to be independent of temperature.

Casey, A.; Arnold, F.; Levitin, L. V.; Lusher, C. P.; Nyki, J.; Saunders, J.; Shibahara, A.; van der Vliet, H.; Yager, B.; Drung, D.; Schurig, Th.; Batey, G.; Cuthbert, M. N.; Matthews, A. J.

2014-06-01

360

Measuring the Temperature of Hot Nuclear Fragments  

E-print Network

A new thermometer based on fragment momentum fluctuations is presented. This thermometer exhibited residual contamination from the collective motion of the fragments along the beam axis. For this reason, the transverse direction has been explored. Additionally, a mass dependence was observed for this thermometer. This mass dependence may be the result of the Fermi momentum of nucleons or the different properties of the fragments (binding energy, spin etc..) which might be more sensitive to different densities and temperatures of the exploding fragments. We expect some of these aspects to be smaller for protons (and/or neutrons); consequently, the proton transverse momentum fluctuations were used to investigate the temperature dependence of the source.

S. Wuenschel; A. Bonasera; L. W. May; G. A. Souliotis; R. Tripathi; S. Galanopoulos; Z. Kohley; K. Hagel; D. V. Shetty; K. Huseman; S. N. Soisson; B. C. Stein; S. J. Yennello

2010-03-31

361

Measurement in a marine environment using low cost sensors of temperature and dissolved oxygen  

USGS Publications Warehouse

Continuous records of physical parameters of the marine environment are difficult as well as expensive to obtain. This paper describes preliminary results of an investigative program with the purpose of developing low cost time integrating measurement and averaging devices for water temperature and dissolved oxygen. Measurements were made in an estuarine area of the Chesapeake Bay over two week periods. With chemical thermometers average water temperature for the two week period was found to be equal to average water temperature measured with thermocouples plus or minus 1.0 C. The slow diffusion of oxygen through the semipermiable sides of plastic bottles permitted the use of water filled bottles to obtain averaged oxygen measurements. Oxygen measurements for two week averaging times using 500 ml polyethylene bottles were found to vary from conventionally measured and averaged dissolved oxygen by about 1.8 mg/l. ?? 1974 Estuarine Research Federation.

Godshall, F. A.; Cory, R. L.; Phinney, D. E.

1974-01-01

362

Measurement in a marine environment using low cost sensors of temperature and dissolved oxygen  

Microsoft Academic Search

Continuous records of physical parameters of the marine environment are difficult as well as expensive to obtain. This paper\\u000a describes preliminary results of an investigative program with the purpose of developing low cost time integrating measurement\\u000a and averaging devices for water temperature and dissolved oxygen.\\u000a \\u000a Measurements were made in an estuarine area of the Chesapeake Bay over two week periods.

Fredric A. Godshall; Robert L. Cory; Dale E. Phinney

1974-01-01

363

An Update High-Temperature Superconducting Maglev Measurement System  

Microsoft Academic Search

An update high temperature superconducting Maglev measurement system (SCML-02) was successfully developed. The system includes liquid nitrogen vessel, cylinder permanent magnet (PM) or PM guideway (PMG), data collection and processing, mechanical drive and autocontrol. The liquid nitrogen vessel with high temperature superconductors (HTSCs) can be placed above or under the PM. This measurement system has other characteristics: high measurement precision,

Suyu Wang; Jiasu Wang; Changyan Deng; Yiyu Lu; Youwen Zeng; Honghai Song; Haiyu Huang; Hua Jing; Yonggang Huang; Jun Zheng; Xingzhi Wang; Ya Zhang

2007-01-01

364

Proceedings of the Second Noncontact Temperature Measurement Workshop  

Microsoft Academic Search

The state of the art in noncontact temperature measurement (NCTM) technology was reviewed and the NCTM requirements of microgravity materials processing community identified. The workshop included technical presentations and discussions which ranged from research on advanced concepts for temperature measurement to laboratory research and development regarding measurement principles and state-of-the-art engineering practices for NCTM methodology in commercial and industrial applications.

Robert R. Hale

1989-01-01

365

Relaxation calorimetry technique for measuring low temperature specific heat  

E-print Network

Relaxation calorimetry technique for measuring low temperature specific heat R. W. Newsome, Jr cost measurement of the temperature dependence of the spe- cific heat of a 10 thick copolymer film Received 6 June 2003; accepted 15 October 2003 A rudimentary calorimeter was constructed to measure

Andrei, Eva Y.

366

Collection, Measurement and Treatment of Microorganism Using Dielectrophoretic Micro Devices  

NASA Astrophysics Data System (ADS)

Constant monitoring of manufacturing processes has been essential in food industry because of global expansion of microbial infection. Micro-scale dielectrophoretic method is an attractive technique for direct operation and quantitative detection of bioparticles. The electrical system is capable of rapid and simple treatments corresponding to severe legal control for food safety. In this paper, newly developed techniques are reviewed for bacterial concentration, detection and sterilization using dielectrophoresis in a micro reactor. The perspective to an integrated micro device of those components is also discussed.

Uchida, Satoshi

367

A REAL-TIME MEASURING DEVICE FOR DENSE PARTICULATE SYSTEMS  

EPA Science Inventory

The report describes the design and performance of an instrument, based on the concept of instantaneous intensity ratio, for measuring particle size distributions of dense particulate matter. The method involves simultaneously measuring the intensity of light scattered by a parti...

368

Measurement and device design of left-handed metamaterials  

E-print Network

The properties of a variety of left-handed metamaterial (LHM) structures are analyzed and measured to verify consistent behavior between theory an measurements. The structures are simulated using a commercial software ...

Thomas Zachary M. (Zachary Michael)

2005-01-01

369

Liquid oxygen liquid acquisition device bubble point tests with high pressure lox at elevated temperatures  

NASA Astrophysics Data System (ADS)

When transferring propellant in space, it is most efficient to transfer single phase liquid from a propellant tank to an engine. In earth's gravity field or under acceleration, propellant transfer is fairly simple. However, in low gravity, withdrawing single-phase fluid becomes a challenge. A variety of propellant management devices (PMDs) are used to ensure single-phase flow. One type of PMD, a liquid acquisition device (LAD) takes advantage of capillary flow and surface tension to acquire liquid. The present work reports on testing with liquid oxygen (LOX) at elevated pressures (and thus temperatures) (maximum pressure 1724 kPa and maximum temperature 122 K) as part of NASA's continuing cryogenic LAD development program. These tests evaluate LAD performance for LOX stored in higher pressure vessels that may be used in propellant systems using pressure fed engines. Test data shows a significant drop in LAD bubble point values at higher liquid temperatures, consistent with lower liquid surface tension at those temperatures. Test data also indicates that there are no first order effects of helium solubility in LOX on LAD bubble point prediction. Test results here extend the range of data for LOX fluid conditions, and provide insight into factors affecting predicting LAD bubble point pressures.

Jurns, J. M.; Hartwig, J. W.

2012-04-01

370

Liquid Oxygen Liquid Acquisition Device Bubble Point Tests with High Pressure LOX at Elevated Temperatures  

NASA Technical Reports Server (NTRS)

When transferring propellant in space, it is most efficient to transfer single phase liquid from a propellant tank to an engine. In earth s gravity field or under acceleration, propellant transfer is fairly simple. However, in low gravity, withdrawing single-phase fluid becomes a challenge. A variety of propellant management devices (PMD) are used to ensure single-phase flow. One type of PMD, a liquid acquisition device (LAD) takes advantage of capillary flow and surface tension to acquire liquid. The present work reports on testing with liquid oxygen (LOX) at elevated pressures (and thus temperatures) (maximum pressure 1724 kPa and maximum temperature 122K) as part of NASA s continuing cryogenic LAD development program. These tests evaluate LAD performance for LOX stored in higher pressure vessels that may be used in propellant systems using pressure fed engines. Test data shows a significant drop in LAD bubble point values at higher liquid temperatures, consistent with lower liquid surface tension at those temperatures. Test data also indicates that there are no first order effects of helium solubility in LOX on LAD bubble point prediction. Test results here extend the range of data for LOX fluid conditions, and provide insight into factors affecting predicting LAD bubble point pressures.

Jurns, John M.; Hartwig, Jason W.

2011-01-01

371

Specific capture and temperature-mediated release of cells in an aptamer-based microfluidic device  

PubMed Central

Isolation of cells from heterogeneous mixtures is critically important in both basic cell biology studies and clinical diagnostics. Cell isolation can be realized based on physical properties such as size, density and electrical properties. Alternatively, affinity binding of target cells by surface-immobilized ligands, such as antibodies, can be used to achieve specific cell isolation. Microfluidics technology has recently been used in conjunction with antibody-based affinity isolation methods to capture, purify and isolate cells with higher yield rates, better efficiencies and lower costs. However, a method that allows easy release and collection of live cells from affinity surfaces for subsequent analysis and detection has yet to be developed. This paper presents a microfluidic device that not only achieves specific affinity capture and enrichment, but also enables non-destructive, temperature-mediated release and retrieval of cells. Specific cell capture is achieved using surface-immobilized aptamers in a microchamber. Release of the captured cells is realized by a moderate temperature change, effected via integrated heaters and a temperature sensor, to reversibly disrupt the cell-aptamer interaction. Experimental results with CCRF-CEM cells have demonstrated that the device is capable of specific capture and temperature-mediated release of cells, that the released cells remain viable and that the aptamer-functionalized surface is regenerable. PMID:22854859

Zhu, Jing; Nguyen, ThaiHuu; Pei, Renjun; Stojanovic, Milan; Lin, Qiao

2014-01-01

372

Pitot tube as a calibration device for turbulence measurement  

Microsoft Academic Search

It is demonstrated that a pitot tube can be used to calibrate hot-wire turbulence measurements. Expressions are given that make it possible to correct hot-wire measurements for the effects of the tangential velocity component and high turbulence intensity by using a pitot tube to measure the mean velocity in fully developed turbulent pipe flow. It is suggested that the pitot

Sadek Z. Kassab

1990-01-01

373

Temperature measurement. [liquid monopropellant rocket engine performance tests  

NASA Technical Reports Server (NTRS)

The design, installation, checkout, calibration, and operation of a temperature measuring system to be used during tests of a liquid monopropellant rocket engine are discussed. Appendixes include: (1) temperature measurement system elemental uncertainties, and (2) tables and equations for use with thermocouples and resistance thermometers. Design guidelines are given for the critical components of each portion of the system to provide an optimum temperature measurement system which meets the performance criteria specified.

1979-01-01

374

[Welding arc temperature field measurements based on Boltzmann spectrometry].  

PubMed

Arc plasma, as non-uniform plasma, has complicated energy and mass transport processes in its internal, so plasma temperature measurement is of great significance. Compared with absolute spectral line intensity method and standard temperature method, Boltzmann plot measuring is more accurate and convenient. Based on the Boltzmann theory, the present paper calculates the temperature distribution of the plasma and analyzes the principle of lines selection by real time scanning the space of the TIG are measurements. PMID:23240385

Si, Hong; Hua, Xue-Ming; Zhang, Wang; Li, Fang; Xiao, Xiao

2012-09-01

375

Self-Calibrating Infrared Thermometer for Low-Temperature Measurement  

Microsoft Academic Search

This paper presents a self-calibration technique for the removal of measurement errors caused by thermal gradi- ents in thermopile-based infrared thermometry, particularly when measuring low temperatures. Applications for this self-calibration method include low-temperature measurement in the food indus- try and infrared thermometers for remote temperature monitor- ing in cold climates. The self-calibration technique reported in this paper is shown to

Tim Barry; Gary Fuller; Khaled Hayatleh; John Lidgey

2011-01-01

376

Temperature Measurement of a Glass Material Using a Multiwavelength Pyrometer  

NASA Technical Reports Server (NTRS)

Temperature measurement of a substance that is transparent using the traditional 1-color, 2-color and other pyrometers has been difficult. The radiation detected by pyrometers do not come from a well defined location in the transparent body. The multiwavelength pyrometer developed at the NASA Lewis Research Center can measure the surface temperature of many materials. We show in this paper that it also measures the surface and a bulk subsurface temperature of transparent materials like glass.

Ng, Daniel

1997-01-01

377

Fiber Bragg grating sensor for the simultaneous measurement of stress and temperature in high temperature environment  

Microsoft Academic Search

A novel fiber Bragg grating sensor operating in the environment of high temperature is studied. And the sensor can realize the simultaneous measurement of stress and temperature. The sensing head is comprised of one metal strip, one adiabatic strip and two FBGs with the same specification. The metal strip converts the measured temperature into the strain of the FBG2, and

Fang Li; Yuesong Jiang

2008-01-01

378

Cryogenic temperature measurement for large applications  

E-print Network

We have developed a resistance thermometry system for the acquisition, control and monitoring of temperature in large-scale cryogenic applications. The resistance of the sensor is converted to a voltage using a self-balancing AC bridge circuit featuring square-wave excitation currents down to 1 nA. The system is easily scalable and includes intelligent features to treat special situations such as magnet quenches differently from normal operation.

Ylstalo, J; Kyynrinen, J; Niinikoski, T O; Voutilainen, R

1996-01-01

379

Active radiometer for self-calibrated furnace temperature measurements  

DOEpatents

Radiometer with a probe beam superimposed on its field-of-view for furnace temperature measurements. The radiometer includes a heterodyne millimeter/submillimeter-wave receiver including a millimeter/submillimeter-wave source for probing. The receiver is adapted to receive radiation from a surface whose temperature is to be measured. The radiation includes a surface emission portion and a surface reflection portion which includes the probe beam energy reflected from the surface. The surface emission portion is related to the surface temperature and the surface reflection portion is related to the emissivity of the surface. The simultaneous measurement of surface emissivity serves as a real time calibration of the temperature measurement.

Woskov, Paul P. (Bedford, MA); Cohn, Daniel R. (Chestnut Hill, MA); Titus, Charles H. (Newtown Square, PA); Wittle, J. Kenneth (Chester Springs, PA); Surma, Jeffrey E. (Kennewick, WA)

1996-01-01

380

High-throughput, temperature-controlled microchannel acoustophoresis device made with rapid prototyping  

NASA Astrophysics Data System (ADS)

We report a temperature-controlled microfluidic acoustophoresis device capable of separating particles and transferring blood cells from undiluted whole human blood at a volume throughput greater than 1 L h-1. The device is fabricated from glass substrates and polymer sheets in microscope-slide format using low-cost, rapid-prototyping techniques. This high-throughput acoustophoresis chip (HTAC) utilizes a temperature-stabilized, standing ultrasonic wave, which imposes differential acoustic radiation forces that can separate particles according to size, density and compressibility. The device proved capable of separating a mixture of 10- and 2-?m-diameter polystyrene beads with a sorting efficiency of 0.8 at a flow rate of 1 L?h-1. As a first step toward biological applications, the HTAC was also tested in processing whole human blood and proved capable of transferring blood cells from undiluted whole human blood with an efficiency of 0.95 at 1 L?h-1 and 0.82 at 2 L?h-1.

Adams, Jonathan D.; Ebbesen, Christian L.; Barnkob, Rune; Yang, Allen H. J.; Soh, H. Tom; Bruus, Henrik

2012-07-01

381

High-temperature superconducting superconductor/normal metal/superconducting devices  

NASA Technical Reports Server (NTRS)

We describe the fabrication and characterization of superconductor/normal metal/superconductor (SNS) devices made with the high-temperature superconductor (HTS) YBa2Cu3O(7-x). Structures of YBa2Cu3O(7-x)/Au/Nb on c-axis-oriented YBa2Cu3O(7-x) were made in both sandwich and edge geometries in order to sample the HTS material both along and perpendicular to the conducting a-b planes. These devices display fairly ideal Josephson properties at 4.2 K. In addition, devices consisting of YBa2Cu3O(7-x)/YBa2Cu3O(y)/YBa2Cu3O(7-x), with a 'normal metal' layer of reduced transition temperature YBa2Cu3O(7-x) were fabricated and show a great deal of promise for applications near 77 K. Current-voltage characteristics like those of the Resistively-Shunted Junction model are observed, with strong response to 10 GHz radiation above 60 K.

Foote, M. C.; Hunt, B. D.; Bajuk, L. J.

1991-01-01

382

Development of a Force Measurement Device for Lower-Body Muscular Strength Measuring of Skaters  

NASA Astrophysics Data System (ADS)

This paper presents a force measurement system that can measure a lower-body muscular strength of skaters. The precise measurement and analysis of the left and right lower-body strength of skaters is necessary, because a left/right lower-body strength balance is helpful to improve the athletes' performance and to protect them from injury. The system is constructed with a skate sliding board, a couple of sensor-units with load cell, indicator and control box, guard, force pad, and support bracket. The developed force measurement system is calibrated by the calibration setup, and the uncertainty of the force sensing unit on the left is within 0.087% and the uncertainty of the force sensing unit on the right is within 0.109%. In order to check the feasibility of the developed measurement device, a kinematic analysis is conducted with skater. As a result, the subject shows the deviation of left and right of 12.1 N with respect to average strength and 39.1 N with respect to the maximum strength. This evaluation results are reliable enough to make it possible to measure a lower-body muscular strength of skaters. The use of this measurement system will be expected to correct the posture of skaters and record the sports dynamics data for each athlete. It is believed that through the development of this equipment, skaters in elementary, middle, high schools, colleges, and the professional level have the systematic training to compete with world-class skaters.

Kim, Dong Ki; Lee, Jeong Tae

383

A simple laser-based device for simultaneous microbial culture and absorbance measurement  

NASA Astrophysics Data System (ADS)

In this work we present a device specifically designed to study microbial growth with several applications related to environmental microbiology and other areas of research as astrobiology. The Automated Measuring and Cultivation device (AMC-d) enables semi-continuous absorbance measurements directly during cultivation. It can measure simultaneously up to 16 samples. Growth curves using low and fast growing microorganism were plotted, including Escherichia coli and Haloferax volcanii, a halophilic archaeon.

Abrevaya, X. C.; Cortn, E.; Areso, O.; Mauas, P. J. D.

2013-07-01

384

Laser welding assembling of an implantable bio-medical device: investigation of temperature field  

NASA Astrophysics Data System (ADS)

Laser welding is a commonly used process to assemble medical devices. The heat produced during the laser welding process may have an adverse effect on the mechanical integrity of the case assembly and the functionality of heat sensitive electronic components. In order to maintain the mechanical integrity of the case assembly and to protect the subcomponents, it is important to control the temperature in the assembling process, the investigation of the temperature distribution in the assembly during laser welding is thus necessary. In this paper, we report an experimental method and a numerical simulation for the investigation of the temperature field in the process of laser welding the eyelet to the case subassembly of the Functional Electrical Battery Powered Microstimulator (FEBPM). A pulsed 1064nm Nd:YAG laser is used as an example in this paper.

Lin, Yaomin; Jiang, Guangqiang; Calderon, Joseph L.

2011-03-01

385

Influence of dynamic temperature adjustments during growth on the material properties of CZT radiation devices  

NASA Astrophysics Data System (ADS)

There are several challenges in producing detector grade material based on Cadmium Zinc Telluride (CZT), which include material synthesis and growth of electrically compensated crystals as well as the extraction of high resistivity material suitable for device applications. One of the challenges towards producing large volumes of compensated material using the Vertical Gradient Freeze (VGF) method is the axial and radial variations in material homogeneity. Growth induced strain is one of the most important factors in the crystal growth of CZT because of the low critically resolved shear stress (CRSS) value for this material. In this work, methods to reduce the thermo-mechanical stress imparted into the crystal have been implemented. Specifically, crystals have been grown under dynamic temperature gradients to minimize the temperature gradient across the ingot, while maintaining relatively higher temperature gradients at the Solid Liquid Interface (SLI). How this adjustment affects bulk resistivity and photoconductivity has been investigated.

Crocco, J.; Bensalah, H.; Zheng, Q.; Castaldini, A.; Fraboni, B.; Cavalcoli, D.; Cavallini, A.; Dieguez, E.

2012-12-01

386

Acoustic temperature measurement in a rocket noise field.  

PubMed

A 1 ?m diameter platinum wire resistance thermometer has been used to measure temperature fluctuations generated during a static GEM-60 rocket motor test. Exact and small-signal relationships between acoustic pressure and acoustic temperature are derived in order to compare the temperature probe output with that of a 3.18 mm diameter condenser microphone. After preliminary plane wave tests yielded good agreement between the transducers within the temperature probe's ?2 kHz bandwidth, comparison between the temperature probe and microphone data during the motor firing show that the ?3 K acoustic temperature fluctuations are a significant contributor to the total temperature variations. PMID:21117711

Giraud, Jarom H; Gee, Kent L; Ellsworth, John E

2010-05-01

387

Temperature Measurement of Ceramic Materials Using a Multiwavelength Pyrometer  

NASA Technical Reports Server (NTRS)

The surface temperatures of several pure ceramic materials (alumina, beryllia, magnesia, yittria and spinel) in the shape of pellets were measured using a multiwavelength pyrometer. In one of the measurements, radiation signal collection is provided simply by an optical fiber. In the other experiments, a 4.75 inch (12 cm) parabolic mirror collects the signal for the spectrometer. Temperature measurement using the traditional one- and two-color pyrometer for these ceramic materials is difficult because of their complex optical properties, such as low emissivity which varies with both temperature and wavelength. In at least one of the materials, yittria, the detected optical emission increased as the temperature was decreased due to such emissivity variation. The reasons for such changes are not known. The multiwavelength pyrometer has demonstrated its ability to measure surface temperatures under such conditions. Platinum electrodes were embedded in the ceramic pellets for resistance measurements as the temperature changed.

Ng, Daniel; Fralick, Gustave

1999-01-01

388

Multi-spectral pyrometer for gas turbine blade temperature measurement  

NASA Astrophysics Data System (ADS)

To achieve the highest possible turbine inlet temperature requires to accurately measuring the turbine blade temperature. If the temperature of blade frequent beyond the design limits, it will seriously reduce the service life. The problem for the accuracy of the temperature measurement includes the value of the target surface emissivity is unknown and the emissivity model is variability and the thermal radiation of the high temperature environment. In this paper, the multi-spectral pyrometer is designed provided mainly for range 500-1000, and present a model corrected in terms of the error due to the reflected radiation only base on the turbine geometry and the physical properties of the material. Under different working conditions, the method can reduce the measurement error from the reflect radiation of vanes, make measurement closer to the actual temperature of the blade and calculating the corresponding model through genetic algorithm. The experiment shows that this method has higher accuracy measurements.

Gao, Shan; Wang, Lixin; Feng, Chi

2014-09-01

389

Transcutaneous Bilirubin Measurement: A Multicenter Evaluation of a New Device  

Microsoft Academic Search

Objectives. The early discharge of neonates from hospitals makes transcutaneous measurement of total bilirubin concentration a useful tool to monitor neonatal jaundice. The objectives of this study were to determine whether 1) transcutaneous bilirubin (TcB) measurement, as performed using BiliCheck (BC), correlates with total serum bilirubin (TSB) levels, measured with standard laboratory methods and with high-pressure liquid chromatography (HPLC-B); 2)

Firmino F. Rubaltelli; Glenn R. Gourley; Norbert Loskamp; Neena Modi; Matthias Roth-Kleiner; Alfred Sender; Paul Vert

390

[Influence of exercise on horses' limb volume, measured by an optoelectronic device].  

PubMed

This study tested for the first time an optoelectronic device (Perometer*) measuring limb volume of horses. An analysis of its application was performed regarding the influence of different types of physical exercise on the volume of the extremities. 40 horses were divided into four groups often horses, each group being exposed to exercise, differing in kind and duration of lunging, horse-ridden and riderless. The volume measurement was performed by determining the inactive value (I) after a twelfe-hour standing period, the load value (II) immediately after exercise and recovery value (III) one hour after exercise. The results showed a highly significant decrease in limb volume of 5.7% between values (I) and (II), as well as a highly significant increase of 68% between (II) and (III). The volume changes observed in male horses were significantly higher than in female horses. Volume changes in horse-ridden groups were higher than riderless ones, but not significant. There were fewer leg volume changes at low ambient temperatures (1-12 degrees C) compared to high temperatures (23-31 degrees C), but these were not statistically significant. Well-trained horses showed lower volume changes than less trained horses (not statistically significant). The Perometer is a fast and reliable tool for measuring limb volume of horses. The ICC (Interclass Correlation Coefficient) calculated a high measurement reproducibility of 0.996. A variance analysis showed no significant differences between the three repeated leg measurements. Thus, the Perometer can be used for monitoring and quantifying edema and documenting limb volume changes resulting from training, wearing compression stockings or bandages, manual lymph drainage. PMID:22059298

Siewert, Carsten; Bttcher, Ariane; Hellige, Maren; Beyerbach, Martin; von Rautenfeld, Dirk Berens; Seifert, Hermann

2011-01-01

391

Autonomous System for MISSE Temperature Measurements  

NASA Technical Reports Server (NTRS)

The Materials International Space Station Experiment (MISSE) is scheduled to be deployed during the summer of 2001. This experiment is a cooperative endeavor by NASA-LaRC, NASA-GRC, NASA MSFC, NASA-JSC, the Materials Laboratory at the Air Force Research Laboratory, and the Boeing Phantom Works. The objective of the experiment is to evaluate performance, stability, and long term survivability of materials and components planned for use by NASA and DOD on future LEO, synchronous orbit, and interplanetary space missions. Temperature is an important parameter in the evaluation of space environmental effects on materials.

Harvey, G. A.; Lash, T. J.; Kinard, W. H.; Bull, K.; deGeest, F.

2001-01-01

392

Highly simplified device for measuring the intensity and phase of picosecond pulses.  

PubMed

We demonstrate an extremely simple frequency-resolved-optical-gating (GRENOUILLE) device for measuring the intensity and phase of relatively long--ps--pulses. In order to achieve the required high spectral resolution and large temporal range, it uses a few-cm-thick second-harmonic-generation crystal in the shape of a pentagon. This has the additional advantage of reducing the device's total number of components to as few as three simple easily aligned optics, making it the simplest device ever developed for complete pulse measurement. We report complete intensity-and-phase measurements of pulses up to 15ps long with a time-bandwidth product of 21. PMID:20721133

Cohen, Jacob; Lee, Dongjoo; Chauhan, Vikrant; Vaughan, Peter; Trebino, Rick

2010-08-01

393

Measurement and Analysis of Precipitation Temperatures and Their Potential as Non-Conservative Tracer for Understanding Rainfall-Runoff Processes  

NASA Astrophysics Data System (ADS)

In this study, we investigate the potential of temperature as non-conservative tracer to improve the understanding of rainfall-runoff processes. The idea is that for those events where there is a sufficient difference between precipitation temperature and water (i.e. discharge) temperature in a river, the change of water temperature after the onset of a rainfall will allow some conclusions about the rainfall-runoff process. We constructed a simple, low cost device which allows a continuous measurement of precipitation temperatures. These measurements were carried out at a meteorological station, where parameters like rainfall intensity, air temperature as well as data from vertical pointing micro rain radar were logged in high temporal resolution together with the precipitation temperatures. We present the first results of these measurements for typical rainfall events and address relevant questions like the stability of precipitation temperatures during rainfall events and the behavior of air temperature and precipitation temperature.

Seidel, Jochen; Brdossy, Andrs; Genkinger, Elena

2014-05-01

394

An Integrated-Circuit Temperature Sensor for Calorimetry and Differential Temperature Measurement.  

ERIC Educational Resources Information Center

Describes the application of an integrated-circuit (IC) chip which provides an easy-to-use, inexpensive, rugged, computer-interfaceable temperature sensor for calorimetry and differential temperature measurement. Discusses its design and advantages. (JRH)

Muyskens, Mark A.

1997-01-01

395

An Electronic Device for the Measurement of Sweat Rates  

Microsoft Academic Search

A new method for the continuous measurement and recording of sweat rate has been developed. The sweat rate is determined by continuously measuring the change in resistance of a sensing element which, in turn, reflects the change in moisture content of a small volume of air. In operation, a chamber containing the element is fastened against the skin. Dry air

O. Z. Roy

1960-01-01

396

Measuring devices for precision manufacturing and quality control  

Microsoft Academic Search

Various miniaturized and low cost transducers were developed for different applications in metrology, precision manufacturing and fabrication control. They comprise: (1) photoelectric linear transducer with micron step pression; (2) incremental and coded transducers; (3) concave mirror x-y transducer; (4) correlation systems for linear and speed measurements; (5) high resolution angle transducers; and (6) correlation optical sensor for distance measurement. Operation

J. Wilhelm; H. D. Jacoby; H. J. Preuss

1980-01-01

397

ULTRASONIC DEVICE DEVELOPMENT FOR SEWAGE VELOCITY AND SEDIMENT CONCENTRATION MEASUREMENTS  

Microsoft Academic Search

A major concern in waste water management is the real time pollutant flow measurement and identification. Traditional acoustic instruments only allow mean velocity or flow measurement. Concentration of solid pollutants, namely suspended sediments, is obtained through dessication of water samples. In the frame of a technological research and innovation network in water and environment technologies (RITEAU), our research group, in

Fars ABDA; Abdelhalim AZBAID; Denis ENSMINGER; Pierre FRANCOIS; Philippe SCHMITT

398

Power oscillation damping control strategies for FACTS devices using locally measurable quantities  

SciTech Connect

This paper presents a way to derive power oscillation damping control strategies for Flexible AC Transmission (FACTS) devices, and derives these laws for the four major types of FACTs devices using an energy function (Lyapunov) method. All controls rely only on locally measurable information, and are independent of system topology, implying structural uncertainty need not affect power oscillation damping control strategies.

Gronquist, J.F.; Sethares, W.A.; Alvarado, F.L.; Lasseter, R.H. [Univ. of Wisconsin, Madison, WI (United States)] [Univ. of Wisconsin, Madison, WI (United States)

1995-08-01

399

Power oscillation damping control strategies for FACTS devices using locally measurable quantities  

Microsoft Academic Search

This paper presents a way to derive power oscillation damping control strategies for flexible AC transmission system (FACTS) devices, and derives these laws for the four major types of FACTS devices using an energy function (Lyapunov) method. All controls rely only on locally measurable information, and are independent of system topology, implying structural uncertainty need not affect power oscillation damping

James F. Gronquist; William A. Sethares; Fernando L. Alvarado; Robert H. Lasseter

1995-01-01

400

Instruments and Methods for Calibration of Oscillometric Blood Pressure Measurement Devices  

Microsoft Academic Search

Most of automatic blood pressure measurement devices on the market implement an oscillometric method. This paper highlights the need for standardized calibration procedures for these devices in order to reduce logistical difficulties, time-consuming processes, and high costs involved in clinical validations. A critical overview of researchers' and manufacturers' proposals to answer this need is presented as a contribution to the

Eulalia Balestrieri; Sergio Rapuano

2010-01-01

401

An assessment of the Value of Certain Measuring Devices for Identifying Creative Writing Performance.  

ERIC Educational Resources Information Center

The purposes of this study were to assess the individual and relative value of seven types of measuring devices for identifying students with creative writing ability, also to determine which of the devices comprised the best small predictor battery for indicating creative talent. Of the nearly thirty "predictor" variable scores derived from the

Taylor, J. Lewis

402

Calibration accuracy of hospital-based non-invasive blood pressure measuring devices  

Microsoft Academic Search

Accurate blood pressure (BP) measurement is dependent on a trained observer using validated and properly maintained equipment. BP devices should be checked regularly to ensure that their calibration remains within the European Standard specification of 3 mm Hg. This study assessed the air leakage rates and calibration accuracy of BP devices in use at a large teaching hospital, using a

A de Greeff; I Lorde; A Wilton; P Seed; A J Coleman; A H Shennan; AH Shennan

2010-01-01

403

A Triaxial-Measurement Shear-Test Device for Soft Biological Tissues  

Microsoft Academic Search

A novel shear-test device for soft biological tissue, capable of applying simple shear deformations simultaneously in two orthogonal directions while measuring the resulting forces generated in three axes, is described. We validated the device using a synthetic gel, the properties of which were ascertained from independent tensile and rotational shear tests. Material parameters for the gel were fitted using neo-Hookean

Socrates Dokos; Ian J. LeGrice; Bruce H. Smaill; Alistair A. Young

2000-01-01

404

High temperature permeameter for measuring magnetic properties  

NASA Technical Reports Server (NTRS)

Instrument for measuring magnetic permeability of materials undergoing heat treatment as method for monitoring stress relief and tempering is described. Procedure is based on magnetic potentiometer principle with yoke compensating coils to cancel effects of reluctance of yoke and joint gaps. Instrument is heated with specimen being heat treated.

Barranger, J. P.

1972-01-01

405

Design and validation of an ambulatory system for the measurement of the microcirculation in the capillaries: microHematron device.  

PubMed

The non-invasive Hematron sensor is an active sensor used in studying skin blood flow (SBF) by measuring thermal conductivity of living tissues. Up to now, the Hematron device was composed of the Hematron probe and a heavy analog conditioning electronics. This paper presents the design, realization and validation of an ambulatory device (microHematron) associated with the original Hematron probe. The electronic architecture is based on a Programmable System on Chip (PSoC), which contributes in reducing the number of discrete components, and consequently, the electronic conditioning circuit of Hematron. The microHematron device can be worn on the wrist of the patient thanks to its size (4x3x1cm3) compared to the non-ambulatory conditioning electronics sized 20x30x20cm3. In addition, data can be stored in a microSD card or transmitted using a ZigBee module. The validation of the microHematron device was performed using the analog conditioning electronics as a reference. Experiments were performed first on a physical model reproducing microcirculation in order to characterize the linearity of the thermal conductivity as a function of water flow. Then, two experiments were hold in-vivo conditions highlighting the performances of this new device. In a first experiment, effects of mental calculation on effective tissue perfusion were measured and in a second one, effects of an anti-cellulite cream on micro-vascularisation and skin temperature were studied. PMID:19963806

Toumi, Dareen; Gehin, Claudine; Dittmar, Andre; McAdams, Eric

2009-01-01

406

Influence of Resistance Method on Motor Winding Temperature Rise Measurement  

NASA Astrophysics Data System (ADS)

The objective of this article is presentation of influences when measuring the motor winding temperature rise in the scope of safety testing of electrical appliances, with respect to conformity assessment. The temperature measurement in testing is one of the most defined fields of measurement, but it is very important how the measurement is performed. Standards only describe that the resistance method shall be used for determination of the temperature rise (heating) of the winding. The temperature rise is defined as the average temperature rise of the windings above the ambient (surrounding) temperature, at the specified load of the unit under test. It is not explicitly defined how to approach this measurement when using cooling characteristics of the winding for determination of the temperature rise. Since the extrapolation curve is used, the procedure is also very important to obtain a result as accurate as possible. It is important that measurement results and their associated uncertainties are correctly evaluated, and on that basis, appropriate conclusions of conformity of the product with specifications are made. The resistance method influence on the motor winding temperature rise measurement is a case study in this article. The article focuses on the measurement of the temperature rise of electrical motors used in electrical appliances according to the standard EN 60335-1, clause 11 (2002) (identical as standard IEC 60335-1, 2001). In this article, the influencing parameters are analyzed when measuring the temperature rise of electromotor winding. As a case study, concrete measurements are presented. The optimal time after which the performer has to start measurement of the cooling characteristics is analyzed, since the motors are typically mounted deep into appliances. Especially for a collector motor winding, it takes some time for a performer to be able to connect the measuring instrument to collector's lamellas because this contact has an important influence on extrapolation results.

Beges, G.

2011-12-01

407

Final Report on the Measurement of the temperature of the  

E-print Network

Final Report on the Measurement of the temperature of the Cosmic Microwave Background Toward investigations of the temperature of the cosmic microwave background using the apparatus developed and electrons, about 3000 K. Before this time / temperature, any neutral atoms formed could immediately be re

408

Spectroscopical temperature measurements in the muzzle fire of artillery rifles  

Microsoft Academic Search

Modified spectroscopic line inversion techniques were used to determine the local and time-based temperature distribution in the flow field outside the muzzle of a rifle immediately after firing. Excitation temperature measurements of Na and K lines in muzzle fires are discussed, and the gas temperature in the various flow ranges is dealt with.

G. Klingenberg

1974-01-01

409

Measurement of Temperature Dependence of Surface Tension of Alcohol Aqueous Solutions by Maximum Bubble Pressure Method  

NASA Astrophysics Data System (ADS)

The surface tension of some high-carbon alcohol aqueous solutions increases as the temperature rises above a certain temperature. There have been attempts to use such special solutions in thermal devices to promote heat transfer. In this study, the authors analyzed the temperature dependence of surface tension of these solutions to investigate this peculiar characteristic in detail. The test fluids were butanol and pentanol aqueous solutions as peculiar solutions, while pure water and ethanol aqueous solution were normal fluids. First, the authors adopted Wilhelmy's method to measure the surface tension during heating, but found that the influence of evaporation of the solution could not be completely eliminated. In this study, the maximum bubble pressure method was employed, which made it possible to isolate the measured solution from ambient air and eliminate the influence of evaporation of the solution. The authors succeeded in measuring the temperature dependence of surface tension, and obtained more reasonable data.

Ono, Naoki; Kaneko, Takahiro; Nishiguchi, Shotaro; Shoji, Masahiro

410

Liquid helium temperature irradiation effects on the operation of 0.7 ? ? ? ?m CMOS devices for cryogenic space applications  

Microsoft Academic Search

Introduction . The difficulties associated with predicting the radiation response of cryogenic circuitry based on room temperature irradiation studies has already been pointed out in the literature (1)-(2). Thus, radiation testing should preferably be performed at operating temperatures, which is not always practical (e.g., practical problems related to operating devices at liquid helium temperatures LHT). The basic reason for the

A. Mercha; Y. Creten; J. Putzeys; P. De Moor; C. Claeys; C. Van Hoof; E. Simoen; A. Mohammadzadeh; R. Nickson

411

CARS Temperature Measurements in Turbulent and Supersonic Facilities  

NASA Technical Reports Server (NTRS)

This paper documents the development of the National Aeronautics and Space Administration s (NASA) Langley Research Center ( LaRC) Coherent Antistokes Raman Spectroscopy (CARS) systems for measurements of temperature in a turbulent subsonic or supersonic reacting hydrogen-air environment. Spectra data provides temperature data when compared to a precalculated library of nitrogen CARS spectra. Library validity was confirmed by comparing CARS temperatures derived through the library with three different techniques for determination of the temperature in hydrogen-air combustion and an electrically heated furnace. The CARS system has been used to survey temperature profiles in the simulated flow of a supersonic combustion ramjet (scramjet) model. Measurement results will be discussed.

Jarrett, O., Jr.; Antcliff, R. R.; Smith, M. W.; Cutler, A. D.; Diskin, G. S.; Northam, G. B.

1991-01-01

412

Research on temperature measurement by X-ray transmission intensity  

NASA Astrophysics Data System (ADS)

The relationship between temperature and X-ray transmission intensity was researched and analyzed by inspecting material density change, which is caused by thermal expansion. A digital radiographic system was employed to obtain the images. On this basis, we deduced the temperature formula based on the average gray level of the captured images. The measured temperatures were obtained from the experiments and the errors were analyzed. We concluded that when X-rays pass through an object, the X-ray strength and the gray level of the image under high temperatures are greater than those under lower temperatures and the image gray level error has great impact on the accuracy of the measured temperature. The presented approach allowed the non-contact temperature measurement of material.

Chen, Shuyue; Cheng, Rong

2013-02-01

413

Measurement of workpiece temperature during welding for welding robot control  

NASA Astrophysics Data System (ADS)

MIG/MAG welding robot seam tracking system based on a symetrically noncontact temperature measurement is presented. Using literature in formation on temperature distribution during welding, a model for the prediction of the behavior of a pyrometer twin is constructed. The temperature difference between the measuring points constitutes the signal for a position control of the twin holding welding torch. As temperature measurement is made impossible by radiation originating from the welding arc, this is done during intermittent welding in time intervals in which the welding arc is switched off.

Illegrams, P. F. A.

414

Digital Devices for Automatic Control: Measurement and Guidance.  

National Technical Information Service (NTIS)

The book considers digital equipment for automatic control and measurement of production processes. It presents the basic characteristics and describes the operating principles of automatic digital instruments, machines for centralized control, and automa...

I. V. Butusov

1967-01-01

415

Measurement of the Magnet Blocks for SSRF Insertion Devices  

SciTech Connect

Two in-vacuum undulators IVU25s and one elliptically polarized undulator EPU100 have been developed for SSRF. Two IVU25s with the same hybrid design contain about 640 Sm{sub 2}Co{sub 17} magnet blocks and the dimension of blocks is 65 Wx25 Hx9 D. The EPU100 of the APPLE-II type contains about 690 NdFeB magnet blocks with the dimension of 35 Wx35 Hx25 D. This paper describes the magnetic measurements of these magnet blocks with the Helmholtz coil measurement system for IVU25 magnet blocks and the Hall probe measurement system for EPU100 magnet blocks. The measured maximum magnetic moment deviation and the maximum angle deviation are less than {+-}1.0% and 1.1 deg. respectively both for Sm{sub 2}Co{sub 17} blocks and NdFeB blocks and satisfy the specifications of undulators.

He Yongzhou; Zhang Jidong; Zhou Qiaogen; Qian Zhenmei; Li Yang [Shanghai Institute of Applied Physics, 239 Zhangheng Road, Pudong District, Shanghai (China)

2010-06-23

416

40 CFR 1065.275 - N2O measurement devices.  

Code of Federal Regulations, 2011 CFR

...determining flush times for your instrument. (4) Gas chromatograph analyzer. You may use a gas chromatograph with an electron-capture detector (GC-ECD) to measure N2 O concentrations of diluted exhaust for batch sampling. (i) You may...

2011-07-01

417

Measuring High Temperatures In Ceramic-Fiber Blankets  

NASA Technical Reports Server (NTRS)

Thermocouple assemblies devised specifically for measuring temperatures at fixed locations within insulating blankets made of such ceramic fibers as alumina, silicon carbide, and/or aluminoborosilicate. Thermocouples measure temperatures from 100 to 3,200 degrees F in oxidizing atmospheres. Wires enclosed in alumina sheath for protection against hot oxidation and mechanical damage.

Kourtides, Demetrius A.

1996-01-01

418

Measurement of bidirectional optical properties of complex shading devices  

SciTech Connect

A new method of predicting the solar heat gain through complex fenestration systems involving nonspecular layers such as shades or blinds has been examined in a project jointly sponsored by ASHRAE and DOE. In this method, a scanning radiometer is used to measure the bidirectional radiative transmittance and reflectance of each layer of a fenestration system. The properties of systems containing these layers are then built up computationally from the measured layer properties using a transmission/multiple-reflection calculation. The calculation produces the total directional-hemispherical transmittance of the fenestration system and the layer-by-layer absorptances. These properties are in turn combined with layer-specific measurements of the inward-flowing fractions of absorbed solar energy to produce the overall solar heat gain coefficient. This paper describes the method of measuring the spatially averaged bidirectional optical properties using an automated, large-sample gonioradiometer/photometer, termed a ``Scanning Radiometer.`` Property measurements are presented for one of the most optically complex systems in common use, a venetian blind. These measurements will form the basis for optical system calculations used to test the method of determining performance.

Klems, J.H.; Warner, J.L.

1995-01-01

419

Survey of spectral response measurements for photovoltaic devices  

SciTech Connect

A survey of the photovoltaic community was conducted to ascertain the present state-of-the-art for PV spectral response measurements. Specific topics explored included measurement system designs, good and bad features of the systems, and problems encountered in the evaluation of specific cell structures and materials. The survey showed that most spectral response data are used in diagnostic analysis for the optimization of developmental solar cells. Measurement systems commonly utilize a chopped narrowband source in conjunction with a constant bias illumination which simulates the ambient end use environment. Researchers emphasized the importance of bias illumination for all types of cells in order to minimize the effects of nonlinearities in cell response. Not surprisingly single crystal silicon cells present the fewest measurement problems to the researcher and have been studied more thoroughly than any other type of solar cell. But, the accurate characterization of silicon cells is still difficult and laboratory intercomparison studies have yielded data scatter ranging from +-5% to +-15%. The measurement experience with other types of cells is less extensive. The development of reliable data bases for some solar cells is complicated by problems of cell nonuniformity, environmental instability, nonlinearity, etc. Cascade cells present new problems associated with their structue (multiple cells in series) which are just beginning to be understood. In addition, the importance of many measurement parameters (spectral content of bias light, bias light intensity, bias voltage, chopping frequency, etc.) are not fully understood for most types of solar cells.

Hartman, J.S.; Lind, M.A.

1981-11-01

420

2D surface temperature measurement of plasma facing components with modulated active pyrometry  

NASA Astrophysics Data System (ADS)

In nuclear fusion devices, such as Tore Supra, the plasma facing components (PFC) are in carbon. Such components are exposed to very high heat flux and the surface temperature measurement is mandatory for the safety of the device and also for efficient plasma scenario development. Besides this measurement is essential to evaluate these heat fluxes for a better knowledge of the physics of plasma-wall interaction, it is also required to monitor the fatigue of PFCs. Infrared system (IR) is used to manage to measure surface temperature in real time. For carbon PFCs, the emissivity is high and known (? 0.8), therefore the contribution of the reflected flux from environment and collected by the IR cameras can be neglected. However, the future tokamaks such as WEST and ITER will be equipped with PFCs in metal (W and Be/W, respectively) with low and variable emissivities (? 0.1-0.4). Consequently, the reflected flux will contribute significantly in the collected flux by IR camera. The modulated active pyrometry, using a bicolor camera, proposed in this paper allows a 2D surface temperature measurement independently of the reflected fluxes and the emissivity. Experimental results with Tungsten sample are reported and compared with simultaneous measurement performed with classical pyrometry (monochromatic and bichromatic) with and without reflective flux demonstrating the efficiency of this method for surface temperature measurement independently of the reflected flux and the emissivity.

Amiel, S.; Loarer, T.; Pocheau, C.; Roche, H.; Gauthier, E.; Aumeunier, M.-H.; Le Niliot, C.; Rigollet, F.; Courtois, X.; Jouve, M.; Balorin, C.; Moncada, V.

2014-10-01

421

Contact Thermocouple Methodology and Evaluation for Temperature Measurement in the Laboratory  

NASA Technical Reports Server (NTRS)

Laboratory testing of advanced aerospace components very often requires highly accurate temperature measurement and control devices, as well as methods to precisely analyze and predict the performance of such components. Analysis of test articles depends on accurate measurements of temperature across the specimen. Where possible, this task is accomplished using many thermocouples welded directly to the test specimen, which can produce results with great precision. However, it is known that thermocouple spot welds can initiate deleterious cracks in some materials, prohibiting the use of welded thermocouples. Such is the case for the nickel-based superalloy MarM-247, which is used in the high temperature, high pressure heater heads for the Advanced Stirling Converter component of the Advanced Stirling Radioisotope Generator space power system. To overcome this limitation, a method was developed that uses small diameter contact thermocouples to measure the temperature of heater head test articles with the same level of accuracy as welded thermocouples. This paper includes a brief introduction and a background describing the circumstances that compelled the development of the contact thermocouple measurement method. Next, the paper describes studies performed on contact thermocouple readings to determine the accuracy of results. It continues on to describe in detail the developed measurement method and the evaluation of results produced. A further study that evaluates the performance of different measurement output devices is also described. Finally, a brief conclusion and summary of results is provided.

Brewer, Ethan J.; Pawlik, Ralph J.; Krause, David L.

2013-01-01

422

2D surface temperature measurement of plasma facing components with modulated active pyrometry.  

PubMed

In nuclear fusion devices, such as Tore Supra, the plasma facing components (PFC) are in carbon. Such components are exposed to very high heat flux and the surface temperature measurement is mandatory for the safety of the device and also for efficient plasma scenario development. Besides this measurement is essential to evaluate these heat fluxes for a better knowledge of the physics of plasma-wall interaction, it is also required to monitor the fatigue of PFCs. Infrared system (IR) is used to manage to measure surface temperature in real time. For carbon PFCs, the emissivity is high and known (? ? 0.8), therefore the contribution of the reflected flux from environment and collected by the IR cameras can be neglected. However, the future tokamaks such as WEST and ITER will be equipped with PFCs in metal (W and Be/W, respectively) with low and variable emissivities (? ? 0.1-0.4). Consequently, the reflected flux will contribute significantly in the collected flux by IR camera. The modulated active pyrometry, using a bicolor camera, proposed in this paper allows a 2D surface temperature measurement independently of the reflected fluxes and the emissivity. Experimental results with Tungsten sample are reported and compared with simultaneous measurement performed with classical pyrometry (monochromatic and bichromatic) with and without reflective flux demonstrating the efficiency of this method for surface temperature measurement independently of the reflected flux and the emissivity. PMID:25362442

Amiel, S; Loarer, T; Pocheau, C; Roche, H; Gauthier, E; Aumeunier, M-H; Le Niliot, C; Rigollet, F; Courtois, X; Jouve, M; Balorin, C; Moncada, V

2014-10-01

423

Evaluation of oscillometric and Doppler ultrasonic devices for blood pressure measurements in anesthetized and conscious dogs.  

PubMed

Two non-invasive blood pressure (NIBP) devices (oscillometry and Doppler) were compared to invasive blood pressure using a Bland-Altman analysis, in anesthetized and conscious dogs. When considering the systolic arterial pressure only during general anesthesia, both NIBP devices slightly underestimated the systolic arterial blood pressure however the precision and the limits of agreement for the Doppler were of a greater magnitude. This indicates a worse clinical performance by the Doppler. The performance of both NIBP devices deteriorated as measured in conscious animals. In general, for the oscillometric device, determination of invasive diastolic and mean arterial pressures was better than the invasive systolic arterial pressure. Overall, the oscillometric device satisfied more of the criteria set by the American College of Veterinary Internal Medicine consensus statement. Based upon these results, the oscillometric device is more reliable than the Doppler in the determination of blood pressure in healthy medium to large breed dogs. PMID:24924217

Vachon, Catherine; Belanger, Marie C; Burns, Patrick M

2014-08-01

424

Single superconducting quantum interference device multiplexer for arrays of low-temperature sensors  

SciTech Connect

We present the design and experimental evaluation of a superconducting quantum interference device (SQUID) multiplexer for an array of low-temperature sensors. Each sensor is inductively coupled to a superconducting summing loop which, in turn, is inductively coupled to the readout SQUID. The flux-locked loop of the SQUID is used to null the current in the summing loop and thus cancel crosstalk. The sensors are biased with an alternating current, each with a separate frequency, and the individual sensor signals are separated by lock-in detection at the SQUID output. We have fabricated a prototype 8 channel multiplexer and discuss the application to a larger array.

Yoon, Jongsoo; Clarke, John; Gildemeister, J. M.; Lee, Adrian T.; Myers, M. J.; Richards, P. L.; Skidmore, J. T.

2001-01-15

425

Single superconducting quantum interference device multiplexer for arrays of low-temperature sensors  

NASA Astrophysics Data System (ADS)

We present the design and experimental evaluation of a superconducting quantum interference device (SQUID) multiplexer for an array of low-temperature sensors. Each sensor is inductively coupled to a superconducting summing loop which, in turn, is inductively coupled to the readout SQUID. The flux-locked loop of the SQUID is used to null the current in the summing loop and thus cancel crosstalk. The sensors are biased with an alternating current, each with a separate frequency, and the individual sensor signals are separated by lock-in detection at the SQUID output. We have fabricated a prototype 8 channel multiplexer and discuss the application to a larger array.

Yoon, Jongsoo; Clarke, John; Gildemeister, J. M.; Lee, Adrian T.; Myers, M. J.; Richards, P. L.; Skidmore, J. T.

2001-01-01

426

Separation of temperature and emittance in remotely sensed radiance measurements  

NASA Technical Reports Server (NTRS)

The remote determination of surface temperature and surface spectral emittance by use of airborne or satellite-borne thermal infrared instruments is not straightforward. The radiance measured is a function of surface temperature, the unknown surface spectral emittance, and absorption and emission in the intervening atmosphere. With a single measurement, the solution for temperature and spectral emittance is undedetermined. This article reviews two of the early approximate methods which have been fairly widely used to approach this problem.

Kahle, Anne B.; Alley, Ronald E.

1992-01-01

427

New type of CCD device for measuring velocity of rail transport  

NASA Astrophysics Data System (ADS)

An optoelectronic device on CCD for measuring velocity is quite a new meter intended for measuring velocity of a locomotive by contactless optical methods with further high- precision determination of a covered distance. The device uses an optical image of railway as well as preliminary velocity values received from other devices installed on the locomotive. Velocity measurement range is from 0 to 250 km/h. The measurement accuracy is 0.5%. The operating principle is based on the use of unique features of a dedicated CCD chip. Owing to a special photozone structure the device can execute moving image filtering according to velocity. Further processing and calculations make it possible to obtain an actual value of velocity in real time mode.

Baklanov, Alexandre I.; Karasev, Vladimir I.; Larionov, Sergei V.; Shilin, Victor A.

1999-10-01

428

Stand Alone Pressure Measurement Device (SAPMD) for the space shuttle Orbiter, part 2  

NASA Technical Reports Server (NTRS)

The Stand Alone Pressure Measurement Device (SAPMD) specifications are examined. The HP.SAPMD GSE software is listed; the HP/SGA readme program is presented; and the SPMD acceptance test procedure is described.

Tomlinson, Bill

1989-01-01

429

564 IEEE ELECTRON DEVICE LETTERS, VOL. 31, NO. 6, JUNE 2010 Temperature-Dependent IV Characteristics of a  

E-print Network

TFET along with its tilted-view SEM image. The device is fabricated on a molecular beam epitaxy (MBE564 IEEE ELECTRON DEVICE LETTERS, VOL. 31, NO. 6, JUNE 2010 Temperature-Dependent I­semiconductor interface, followed by thermal emission into the conduction band. At intermediate gate voltages, pure band

Yener, Aylin

430

High-Temperature and High-Frequency Performance Evaluation of 4H-SiC Unipolar Power Devices  

E-print Network

High-Temperature and High-Frequency Performance Evaluation of 4H-SiC Unipolar Power Devices times greater electric field strength of SiC compared with silicon (Si). 4H-SiC unipolar devices have higher switching speeds due to the higher bulk mobility of 4H-SiC compared to other polytypes. Four

Tolbert, Leon M.

431

A Thermally Annealed Mach-Zehnder Interferometer for High Temperature Measurement  

PubMed Central

An in-fiber Mach-Zehnder interferometer (MZI) for high temperature measurement is proposed and experimentally demonstrated. The device is constructed of a piece of thin-core fiber (TCF) sandwiched between two short sections of multimode fiber (MMF), i.e., a MMF-TCF-MMF structure. A well-defined interference spectrum is obtained owing to the core-mismatch, and the interference dips are sensitive to the ambient temperature. The experimental results show that the proposed interferometer is capable of high temperature measurement up to 875 C with a sensitivity of 92 pm/C over repeated measurements. The explored wavelength drop point may limit the measurement range, which can be improved by repeated thermal annealing. PMID:25093347

Feng, Zhongyao; Li, Jiacheng; Qiao, Xueguang; Li, Ling; Yang, Hangzhou; Hu, Manli

2014-01-01

432

Liquidus temperature and optical properties measurement by containerless techniques  

NASA Technical Reports Server (NTRS)

Reactive alloy liquidus temperatures measured by conventional, contained techniques are often in error due to reactions with containers and gaseous impurities. This paper describes a new liquidus temperature measurement technique that avoids these problems by employing containerless processing. This technique relies on precise and accurate noncontact temperature measurements (NCTM), which are made possible by spectral emissivity values. The spectral emissivities, epsilon(sub lambda), are measured along with the optical properties (real, n, and imaginary, k, components of the index of refraction) using polarimetric techniques on electromagnetically levitated specimens. Results from work done at Vanderbilt University and Intersonics on the Ti-Al system are presented to demonstrate the above techniques.

Anderson, Collin D.

1993-01-01

433

Measuring two ultrashort pulses simultaneously using a single device and on a single shot  

NASA Astrophysics Data System (ADS)

We demonstrate a simple device for measuring two independent ultrashort pulses, each of which can potentially be complex and can also have very different center wavelength, simultaneously in a single-shot. We call our device "double-blind" FROG and it is implemented using a polarization-gate geometry. In polarization-gate "double-blind" FROG, each pulse acts as a reference pulse for the measurement of the other and yields the intensity and phase of both pulses.

Wong, Tsz Chun; Ratner, Justin; Vaughan, Peter; Chauhan, Vikrant; Trebino, Rick

2012-01-01

434

Electrical measurements at the microscale: Air breakdown and silicon Coulomb blockade devices  

NASA Astrophysics Data System (ADS)

In this thesis I describe the work performed in two different areas of research, electrical breakdown of air for small electrode separations and measurements of silicon (Si)-based tunable-barrier single electron transistors (SETs). In this work, I describe a new method for measuring the breakdown of air for the range of electrode separation of interest. This method has several advantages compared to ones found in the literature, namely it allows for a measurement of electrode separation before each breakdown measurement; it has a parallel plate geometry and the surface roughness of the electrodes used is very small. Using the results obtained with this method I have made a quantitative comparison between the predictions of the standard theory of the field (field emission of electrons) and our data, something that has not been done before. In this thesis I describe analytically both the theory and the analysis of our data. I conclude that the standard theory used in this field fails for the range of electrode separations of interest (400 nm to 45 mum). Also, I describe electrical measurements performed on a Si-based tunable-barrier device fabricated in the group of Neil Zimmerman at the National Institute of Standards and Technology (NIST) using the fabrication facilities of Cornell University. I demonstrate that this device can be operated as an SET. I continue by describing measurements of the charge offset drift (Q 0(t)) for this device and show that it is almost 3 orders of magnitude smaller than in metal devices, and comparable to previously measured Si devices of this type. All of the previously measured devices originated from the same fabrication source, NTT, Japan. Our ability to demonstrate the same low drift in devices fabricated at Cornell, USA, indicates that the small values of Q0(t) is a robust property of Si-based devices, and not sensitive to the details of fabrication.

Hourdakis, Emmanouel Spyros

435

Calibration of the depth-measuring device of Rockwell hardness testing machines  

Microsoft Academic Search

In addition to the indirect verification using reference blocks and a reference indenter, it is possible to realise the calibration by direct verification of the test force, the indenter, the depth-measuring device and the testing cycle. Some conditions of the calibration process, e.g. the verification range, and the necessary accuracy of the depth-measuring device are described in standard ISO 6508-2.

F. Lffler; A. Sawla; P. Strobel; Heinrich Bareiss

436

Fabrication of room-temperature operational single-electron devices using Au nanoparticles.  

PubMed

Au nanoparticles (5-10 nm in diameter) single electron devices (SEDs) were fabricated utilizing both electron beam lithography and granular film deposition. Both multiple-tunnel junction (MTJ) and double-tunnel junction (DTJ) were fabricated by adjusting the number of Au nanoparticles between the electrodes. Coulomb blockade effects were clearly observed at room temperature from the MTJs. The threshold voltage of the MTJ-SED with a large gap was about 1.5 V, whereas that with a small gap was about 0.8 V, respectively. When the gap was below 20 nm, a periodic Coulomb staircase was observed from the DTJ-SED at room temperature, where the charging energy was about 0.114 eV. PMID:24745234

Kwon, Namyong; Kim, Kyohyeok; Chung, Ilsub

2014-03-01

437

A Simple Device to Measure Root Growth Rates  

ERIC Educational Resources Information Center

Describes construction and use of a simple auxanometer which students can use to accurately measure root growth rates of intact seedlings. Typical time course data are presented for the effect of ethylene and indole acetic acid on pea root growth. (Author/BR)

Rauser, Wilfried E.; Horton, Roger F.

1975-01-01

438

DESIGN, DEVELOPMENT, AND DEMONSTRATION OF A FINE PARTICULATE MEASURING DEVICE  

EPA Science Inventory

The report describes the design, development, and testing of a fine particulate source monitoring instrument for real-time measurement of mass concentration as a function of aerodynamic particle size. It includes a literature review and selection of the operating principle on whi...

439

IN SITU Device for Real-Time Catalyst Deactivation Measurements  

SciTech Connect

SCR catalyst management has become an important operations and maintenance activity for coal-fired utility boilers in the United States. To facilitate this activity, a method to determine Catalyst Activity in situ is being developed. This report describes the methodology and presents the results of a two ozone season demonstration conducted at Alabama Power Company's Gorgas Unit 10 during the 2005 and 2006 ozone seasons. The results showed that the in situ measurements are in good agreement with the laboratory measurements and the technique has some advantages over the traditional laboratory method of determining Catalyst Activity and Reactor Potential. SCR Performance is determined by the overall Reactor Potential (the product of the Catalyst Activity and the available surface area per unit of flue gas). The in situ approach provides a direct measurement of Reactor Potential under actual operating conditions, whereas laboratory measurements of Catalyst Activity need to be coupled with estimates of catalyst pluggage and flue gas flowrate in order to assess Reactor Potential. The project also showed that the in situ activity results can easily be integrated into catalyst management software to aid in making informed catalyst decisions.

Fossil Energy Research

2008-03-31

440

Distributed spectrum sensing utilizing heterogeneous wireless devices and measurement equipment  

Microsoft Academic Search

A suitable spectrum policy is essential to allow efficient use of the radio spectrum. The Japanese government currently employs a Command and Control (C&C) regime, but measures must be taken to speed up governmental decisions. The first step is to obtain spectrum utilization data which can form the basis of such decisions. This paper describes the design, implementation and evaluation

Junichi Naganawa; Hojun Kim; Shunsuke Saruwatari; Hisashi Onaga; Hiroyuki Morikawa

2011-01-01

441

Pitot tube as a calibration device for turbulence measurement  

Microsoft Academic Search

This note is to demonstrate that one can correct hot-wire turbulence measurements simply by using a Pitot tube to obtain the mean velocity distribution in fully developed, turbulent pipe flow. The basic idea is simply a combination of two independent derivations given in the late sixties. A test case is given to prove the idea.

Sadek Z. Kassab

1990-01-01

442

Split pipe testing device for the measurement of bond of reinforcement under controlled confinement  

NASA Astrophysics Data System (ADS)

This patent discloses a method and apparatus for determining the stress-slip relationship of specimens in concrete including a pipe with a plurality of longitudinal slots evenly spaced around the circumference of the pipe, a specimen and concrete block located in one end of the pipe, a confining device for applying a constant force to the circumference of the concrete block before, during and after a test, a device for measuring the displacement of the specimen relative to the concrete block, and a device for measuring the radial displacement of the concrete block.

Malvar, Javier

1994-07-01

443

Detection and measurement of electroreflectance on quantum cascade laser device using Fourier transform infrared microscope  

SciTech Connect

We demonstrate the use of a Fourier Transform Infrared microscope system to detect and measure electroreflectance (ER) from mid-infrared quantum cascade laser (QCL) device. To characterize intersubband transition (ISBT) energies in a functioning QCL device, a microscope is used to focus the probe on the QCL cleaved mirror. The measured ER spectra exhibit resonance features associated to ISBTs under applied electric field in agreement with the numerical calculations and comparable to observed photocurrent, and emission peaks. The method demonstrates the potential as a characterization tool for QCL devices.

Enobio, Eli Christopher I.; Ohtani, Keita; Ohno, Yuzo; Ohno, Hideo, E-mail: ohno@riec.tohoku.ac.jp [Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan)] [Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan)

2013-12-02

444

Method for local temperature measurement in a nanoreactor for in situ high-resolution electron microscopy.  

PubMed

In situ high-resolution transmission electron microscopy (TEM) of solids under reactive gas conditions can be facilitated by microelectromechanical system devices called nanoreactors. These nanoreactors are windowed cells containing nanoliter volumes of gas at ambient pressures and elevated temperatures. However, due to the high spatial confinement of the reaction environment, traditional methods for measuring process parameters, such as the local temperature, are difficult to apply. To address this issue, we devise an electron energy loss spectroscopy (EELS) method that probes the local temperature of the reaction volume under inspection by the electron beam. The local gas density, as measured using quantitative EELS, is combined with the inherent relation between gas density and temperature, as described by the ideal gas law, to obtain the local temperature. Using this method we determined the temperature gradient in a nanoreactor in situ, while the average, global temperature was monitored by a traditional measurement of the electrical resistivity of the heater. The local gas temperatures had a maximum of 56 C deviation from the global heater values under the applied conditions. The local temperatures, obtained with the proposed method, are in good agreement with predictions from an analytical model. PMID:23831940

Vendelbo, S B; Kooyman, P J; Creemer, J F; Morana, B; Mele, L; Dona, P; Nelissen, B J; Helveg, S

2013-10-01

445

A New Device for Mechanical Testing of Blood Vessels at Cryogenic Temperatures  

PubMed Central

As part of an ongoing program to study the thermo-mechanical effects associated with cryopreservation via vitrification (vitreous in Latin means glassy), the current study focuses on the development of a new device for mechanical testing of blood vessels at cryogenic temperatures. This device is demonstrated on a bovine carotid artery model, permeated with the cryoprotectant cocktail VS55 and a reference solution of 7.05M DMSO, below glass transition. Results are also presented for crystallized specimens, in the absence of cryoprotectants. Results indicate that the elastic modulus of a specimen with no cryoprotectant, at about ?140C (8.6C and 15.5C below the glass transition temperature of 7.05M DMSO and VS55, respectively), is 1038.8 25.2 MPa, which is 8% and 3% higher than that of a vitrified specimen permeated with 7.05M DMSO and VS55, respectively. The elastic modulus of a crystallized material at ?50C is lower by ~20% lower from that at ?140C. PMID:18958183

Jimenez Rios, Jorge L.; Rabin, Yoed

2008-01-01

446

A novel method of sensing temperatures of magnet coils of SINP-MaPLE plasma device  

NASA Astrophysics Data System (ADS)

A set of 36 magnet coils is used to produce a continuous, uniform magnetic field of about 0.35 Tesla inside the vacuum chamber of the MaPLE Device, a linear laboratory plasma device (3 m long and 0.30 m in diameter) built for studying basic magnetized plasma physics phenomena. To protect the water cooled-coils from serious damage due to overheating temperatures of all the coils are monitored electronically using low cost temperature sensor IC chips, a technique first being used in similar magnet system. Utilizing the Parallel Port of a Personal Computer a novel scheme is used to avoid deploying microprocessor that is associated with involved circuitry and low level programming to address and control the large number of sensors. The simple circuits and a program code to implement the idea are developed, tested and presently in operation. The whole arrangement comes out to be not only attractive, but also simple, economical and easy to install elsewhere.

Pal, A. M.; Bhattacharya, S.; Biswas, S.; Basu, S.; Pal, R.

2014-03-01

447

Device for on-the-water measurement of rowing output  

Microsoft Academic Search

All those who compete in the sport of rowing have used the land rowing machine, Ergometer (commonly called the erg), manufactured\\u000a by Concept II (Morrisville, Vermont, USA). Ergon is the Greek word for work, hence the Ergometer measures work. Rowers are\\u000a commonly ranked according to their erg score. The fault in this ranking is that the land Ergometer cannot account

Kyle C. Pilgeram; Michael J. Delwiche

2006-01-01

448

Temperature influence on non-invasive blood glucose measurement  

NASA Astrophysics Data System (ADS)

Regular monitoring of blood sugar level is important for the management of diabetes. The Near-Infra-Red (NIR) spectroscopy method is a promising approach and this involves some form of contact with the body skin. It is noted that the skin temperature does fluctuate with the environment and physiological conditions and the temperature has an influence on the glucose measurement. In this paper, in-vitro and in-vivo investigations on the temperature influence on blood glucose measurement were studied. The in-vitro results from FTIR spectrometer show that sample temperature has significant influence on water absorption, which significantly affects the glucose absorption measurement. The in-vivo results show that when skin temperature around the measurement site is taken into consideration, the prediction of blood glucose level greatly improves.

Zhang, Xiqin; Yeo, Joon Hock

2009-02-01

449

BRAIN TEMPERATURE MEASUREMENT IN RATS: A COMPARISON OF MICROWAVE AND AMBIENT TEMPERATURE EXPOSURES  

EPA Science Inventory

The brain and core temperatures of rats and rat carcasses exposed to microwave radiation (2450 MHz) or elevated air temperatures were measured in two studies. In general, no substantial evidence for temperature differentials, or hot spots, in the brain of these animals was found....

450

Comparison of Minority Carrier Lifetime Measurements in Superstrate and Substrate CdTe PV Devices  

SciTech Connect

We discuss typical and alternative procedures to analyze time-resolved photoluminescence (TRPL) measurements of minority carrier lifetime (MCL) with the hope of enhancing our understanding of how this technique may be used to better analyze CdTe photovoltaic (PV) device functionality. Historically, TRPL measurements of the fast recombination rate (t{sub 1}) have provided insightful correlation with broad device functionality. However, we have more recently found that t{sub 1} does not correlate as well with smaller changes in device performance, nor does it correlate well with performance differences observed between superstrate and substrate CdTe PV devices. This study presents TRPL data for both superstrate and substrate CdTe devices where both t{sub 1} and the slower TRPL decay (t{sub 2}) are analyzed. The study shows that changes in performance expected from small changes in device processing may correlate better with t{sub 2}. Numerical modeling further suggests that, for devices that are expected to have similar drift field in the depletion region, effects of changes in bulk MCL and interface recombination should be more pronounced in t{sub 2}. Although this technique may provide future guidance to improving CdS/CdTe device performance, it is often difficult to extract statistically precise values for t{sub 2}, and therefore t{sub 2} data may demonstrate significant scatter when correlated with performance parameters.

Gessert, T. A.; Dhere, R. G.; Duenow, J. N.; Kuciauskas, D.; Kanevce, A.; Bergeson, J. D.

2011-01-01

451

Temperature measurement method using temperature coefficient timing for resistive or capacitive sensors  

DOEpatents

A method and apparatus for temperature measurement especially suited for low cost, low power, moderate accuracy implementation. It uses a sensor whose resistance varies in a known manner, either linearly or nonlinearly, with temperature, and produces a digital output which is proportional to the temperature of the sensor. The method is based on performing a zero-crossing time measurement of a step input signal that is double differentiated using two differentiators functioning as respective first and second time constants; one temperature stable, and the other varying with the sensor temperature. 5 figs.

Britton, C.L. Jr.; Ericson, M.N.

1999-01-19

452