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Sample records for redundant temperature measurements

  1. Redundant measurements for controlling errors

    International Nuclear Information System (INIS)

    Ehinger, M.H.; Crawford, J.M.; Madeen, M.L.

    1979-07-01

    Current federal regulations for nuclear materials control require consideration of operating data as part of the quality control program and limits of error propagation. Recent work at the BNFP has revealed that operating data are subject to a number of measurement problems which are very difficult to detect and even more difficult to correct in a timely manner. Thus error estimates based on operational data reflect those problems. During the FY 1978 and FY 1979 R and D demonstration runs at the BNFP, redundant measurement techniques were shown to be effective in detecting these problems to allow corrective action. The net effect is a reduction in measurement errors and a significant increase in measurement sensitivity. Results show that normal operation process control measurements, in conjunction with routine accountability measurements, are sensitive problem indicators when incorporated in a redundant measurement program

  2. Signal validation in nuclear power plants using redundant measurements

    International Nuclear Information System (INIS)

    Glockler, O.; Upadhyaya, B.R.; Morgenstern, V.M.

    1989-01-01

    This paper discusses the basic principles of a multivariable signal validation software system utilizing redundant sensor readings of process variables in nuclear power plants (NPPs). The technique has been tested in numerical experiments, and was applied to actual data from a pressurized water reactor (PWR). The simultaneous checking within one redundant measurement set, and the cross-checking among redundant measurement sets of dissimilar process variables, results in an algorithm capable of detecting and isolating bias-type errors. A case in point occurs when a majority of the direct redundant measurements of more than one process variable has failed simultaneously by a common-mode or correlated failures can be detected by the developed approach. 5 refs

  3. Kinematic control of redundant robots and the motion optimizability measure.

    Science.gov (United States)

    Li, L; Gruver, W A; Zhang, Q; Yang, Z

    2001-01-01

    This paper treats the kinematic control of manipulators with redundant degrees of freedom. We derive an analytical solution for the inverse kinematics that provides a means for accommodating joint velocity constraints in real time. We define the motion optimizability measure and use it to develop an efficient method for the optimization of joint trajectories subject to multiple criteria. An implementation of the method for a 7-dof experimental redundant robot is present.

  4. Quantifying the value of redundant measurements at GCOS Reference Upper-Air Network sites

    Directory of Open Access Journals (Sweden)

    F. Madonna

    2014-11-01

    Full Text Available The potential for measurement redundancy to reduce uncertainty in atmospheric variables has not been investigated comprehensively for climate observations. We evaluated the usefulness of entropy and mutual correlation concepts, as defined in information theory, for quantifying random uncertainty and redundancy in time series of the integrated water vapour (IWV and water vapour mixing ratio profiles provided by five highly instrumented GRUAN (GCOS, Global Climate Observing System, Reference Upper-Air Network stations in 2010–2012. Results show that the random uncertainties on the IWV measured with radiosondes, global positioning system, microwave and infrared radiometers, and Raman lidar measurements differed by less than 8%. Comparisons of time series of IWV content from ground-based remote sensing instruments with in situ soundings showed that microwave radiometers have the highest redundancy with the IWV time series measured by radiosondes and therefore the highest potential to reduce the random uncertainty of the radiosondes time series. Moreover, the random uncertainty of a time series from one instrument can be reduced by ~ 60% by constraining the measurements with those from another instrument. The best reduction of random uncertainty is achieved by conditioning Raman lidar measurements with microwave radiometer measurements. Specific instruments are recommended for atmospheric water vapour measurements at GRUAN sites. This approach can be applied to the study of redundant measurements for other climate variables.

  5. Fault detection in multiply-redundant measurement systems via sequential testing

    International Nuclear Information System (INIS)

    Ray, A.

    1988-01-01

    The theory and application of a sequential test procedure for fault detection and isolation. The test procedure is suited for development of intelligent instrumentation in strategic processes like aircraft and nuclear plants where redundant measurements are usually available for individual critical variables. The test procedure consists of: (1) a generic redundancy management procedure which is essentially independent of the fault detection strategy and measurement noise statistics, and (2) a modified version of sequential probability ratio test algorithm for fault detection and isolation, which functions within the framework of this redundancy management procedure. The sequential test procedure is suitable for real-time applications using commercially available microcomputers and its efficacy has been verified by online fault detection in an operating nuclear reactor. 15 references

  6. A novel redundant INS based on triple rotary inertial measurement units

    Science.gov (United States)

    Chen, Gang; Li, Kui; Wang, Wei; Li, Peng

    2016-10-01

    Accuracy and reliability are two key performances of inertial navigation system (INS). Rotation modulation (RM) can attenuate the bias of inertial sensors and make it possible for INS to achieve higher navigation accuracy with lower-class sensors. Therefore, the conflict between the accuracy and cost of INS can be eased. Traditional system redundancy and recently researched sensor redundancy are two primary means to improve the reliability of INS. However, how to make the best use of the redundant information from redundant sensors hasn’t been studied adequately, especially in rotational INS. This paper proposed a novel triple rotary unit strapdown inertial navigation system (TRUSINS), which combines RM and sensor redundancy design to enhance the accuracy and reliability of rotational INS. Each rotary unit independently rotates to modulate the errors of two gyros and two accelerometers. Three units can provide double sets of measurements along all three axes of body frame to constitute a couple of INSs which make TRUSINS redundant. Experiments and simulations based on a prototype which is made up of six fiber-optic gyros with drift stability of 0.05° h-1 show that TRUSINS can achieve positioning accuracy of about 0.256 n mile h-1, which is ten times better than that of a normal non-rotational INS with the same level inertial sensors. The theoretical analysis and the experimental results show that due to the advantage of the innovative structure, the designed fault detection and isolation (FDI) strategy can tolerate six sensor faults at most, and is proved to be effective and practical. Therefore, TRUSINS is particularly suitable and highly beneficial for the applications where high accuracy and high reliability is required.

  7. A novel redundant INS based on triple rotary inertial measurement units

    International Nuclear Information System (INIS)

    Chen, Gang; Li, Kui; Wang, Wei; Li, Peng

    2016-01-01

    Accuracy and reliability are two key performances of inertial navigation system (INS). Rotation modulation (RM) can attenuate the bias of inertial sensors and make it possible for INS to achieve higher navigation accuracy with lower-class sensors. Therefore, the conflict between the accuracy and cost of INS can be eased. Traditional system redundancy and recently researched sensor redundancy are two primary means to improve the reliability of INS. However, how to make the best use of the redundant information from redundant sensors hasn’t been studied adequately, especially in rotational INS. This paper proposed a novel triple rotary unit strapdown inertial navigation system (TRUSINS), which combines RM and sensor redundancy design to enhance the accuracy and reliability of rotational INS. Each rotary unit independently rotates to modulate the errors of two gyros and two accelerometers. Three units can provide double sets of measurements along all three axes of body frame to constitute a couple of INSs which make TRUSINS redundant. Experiments and simulations based on a prototype which is made up of six fiber-optic gyros with drift stability of 0.05° h −1 show that TRUSINS can achieve positioning accuracy of about 0.256 n mile h −1 , which is ten times better than that of a normal non-rotational INS with the same level inertial sensors. The theoretical analysis and the experimental results show that due to the advantage of the innovative structure, the designed fault detection and isolation (FDI) strategy can tolerate six sensor faults at most, and is proved to be effective and practical. Therefore, TRUSINS is particularly suitable and highly beneficial for the applications where high accuracy and high reliability is required. (paper)

  8. A Multi-objective PMU Placement Method Considering Observability and Measurement Redundancy using ABC Algorithm

    Directory of Open Access Journals (Sweden)

    KULANTHAISAMY, A.

    2014-05-01

    Full Text Available This paper presents a Multi- objective Optimal Placement of Phasor Measurement Units (MOPP method in large electric transmission systems. It is proposed for minimizing the number of Phasor Measurement Units (PMUs for complete system observability and maximizing the measurement redundancy of the system, simultaneously. The measurement redundancy means that number of times a bus is able to monitor more than once by PMUs set. A higher level of measurement redundancy can maximize the total system observability and it is desirable for a reliable power system state estimation. Therefore, simultaneous optimization of the two conflicting objectives are performed using a binary coded Artificial Bee Colony (ABC algorithm. The complete observability of the power system is first prepared and then, single line loss contingency condition is considered to the main model. The efficiency of the proposed method is validated on IEEE 14, 30, 57 and 118 bus test systems. The valuable approach of ABC algorithm is demonstrated in finding the optimal number of PMUs and their locations by comparing the performance with earlier works.

  9. Application of model-based and knowledge-based measuring methods as analytical redundancy

    International Nuclear Information System (INIS)

    Hampel, R.; Kaestner, W.; Chaker, N.; Vandreier, B.

    1997-01-01

    The safe operation of nuclear power plants requires the application of modern and intelligent methods of signal processing for the normal operation as well as for the management of accident conditions. Such modern and intelligent methods are model-based and knowledge-based ones being founded on analytical knowledge (mathematical models) as well as experiences (fuzzy information). In addition to the existing hardware redundancies analytical redundancies will be established with the help of these modern methods. These analytical redundancies support the operating staff during the decision-making. The design of a hybrid model-based and knowledge-based measuring method will be demonstrated by the example of a fuzzy-supported observer. Within the fuzzy-supported observer a classical linear observer is connected with a fuzzy-supported adaptation of the model matrices of the observer model. This application is realized for the estimation of the non-measurable variables as steam content and mixture level within pressure vessels with water-steam mixture during accidental depressurizations. For this example the existing non-linearities will be classified and the verification of the model will be explained. The advantages of the hybrid method in comparison to the classical model-based measuring methods will be demonstrated by the results of estimation. The consideration of the parameters which have an important influence on the non-linearities requires the inclusion of high-dimensional structures of fuzzy logic within the model-based measuring methods. Therefore methods will be presented which allow the conversion of these high-dimensional structures to two-dimensional structures of fuzzy logic. As an efficient solution of this problem a method based on cascaded fuzzy controllers will be presented. (author). 2 refs, 12 figs, 5 tabs

  10. Tilt measurement using inclinometer based on redundant configuration of MEMS accelerometers

    Science.gov (United States)

    Lu, Jiazhen; Liu, Xuecong; Zhang, Hao

    2018-05-01

    Inclinometers are widely used in tilt measurement and their required accuracy is becoming ever higher. Most existing methods can effectively work only when the tilt is less than 60°, and the accuracy still can be improved. A redundant configuration of micro-electro mechanical system accelerometers is proposed in this paper and a least squares method and data processing normalization are used. A rigorous mathematical derivation is given. Simulation and experiment are used to verify its feasibility. The results of a Monte Carlo simulation, repeated 3000 times, and turntable reference experiments have shown that the tilt measure range can be expanded to 0°–90° by this method and that the measurement accuracy of θ can be improved by more than 10 times and the measurement accuracy of γ can be also improved effectively. The proposed method is proved to be effective and significant in practical application.

  11. Mathematical model of process of redundant measurements with uninterrupted influence of measurand on sensing element of sensor

    Directory of Open Access Journals (Sweden)

    Redko V. V.

    2011-12-01

    Full Text Available The paper discusses improvement of accuracy of measurands measurements with the use of measuring channel with nonlinear calibration curve. There is proposed a mathematical model, which describes process of redundant measurements for measuring channel when it’s measurement function is a polynomial of third power.

  12. Determination and compensation of the “reference surface” from redundant sets of surface measurements

    Energy Technology Data Exchange (ETDEWEB)

    Polack, François, E-mail: francois.polack@synchrotron-soleil.fr [Synchrotron SOLEIL, L' Orme des Merisiers, Saint-Aubin, BP48, 91192 Gif-sur-Yvette Cedex (France); Thomasset, Muriel, E-mail: muriel.thomasset@synchrotron-soleil.fr [Synchrotron SOLEIL, L' Orme des Merisiers, Saint-Aubin, BP48, 91192 Gif-sur-Yvette Cedex (France)

    2013-05-11

    When trying to measure an optical surface at utmost absolute precision, the problem of the missing or unknown “reference surface” is often encountered. It is obvious with Fizeau and Michelson's interferometry, where the height difference between the surface under test (SUT) and a reference surface is measured. It is also true from slope measurements in long trace profilers (LTP), where due to small construction errors, the response to a perfectly flat ideal surface can be considered as an unknown reference to be subtracted from the measurement data. As no “perfect artifact” can exist, these references cannot be directly determined. The addition of the unknown reference can severely bias the reconstructed surface when field stitching is applied. The results of ptychography have proved that when a measurement is a function of a unique object function with a translated but unique response function, the redundancy of a large set of data allows accurate reconstructions of the object and response function despite the presence of measurement noise. In the case of LTP and interferometry, the basic problem is linear and can be solved by linear algebra rather than iteratively. The method has been already applied to SOLEIL and ESRF LTPs and is succesfully used on a regular base. We show here that the method can be also applied to interferometry and improve stitching results.

  13. Temperature measurement and control

    CERN Document Server

    Leigh, JR

    1988-01-01

    This book treats the theory and practice of temperature measurement and control and important related topics such as energy management and air pollution. There are no specific prerequisites for the book although a knowledge of elementary control theory could be useful. The first half of the book is an application oriented survey of temperature measurement techniques and devices. The second half is concerned mainly with temperature control in both simple and complex situations.

  14. Auto-Calibration and Fault Detection and Isolation of Skewed Redundant Accelerometers in Measurement While Drilling Systems.

    Science.gov (United States)

    Seyed Moosavi, Seyed Mohsen; Moaveni, Bijan; Moshiri, Behzad; Arvan, Mohammad Reza

    2018-02-27

    The present study designed skewed redundant accelerometers for a Measurement While Drilling (MWD) tool and executed auto-calibration, fault diagnosis and isolation of accelerometers in this tool. The optimal structure includes four accelerometers was selected and designed precisely in accordance with the physical shape of the existing MWD tool. A new four-accelerometer structure was designed, implemented and installed on the current system, replacing the conventional orthogonal structure. Auto-calibration operation of skewed redundant accelerometers and all combinations of three accelerometers have been done. Consequently, biases, scale factors, and misalignment factors of accelerometers have been successfully estimated. By defecting the sensors in the new optimal skewed redundant structure, the fault was detected using the proposed FDI method and the faulty sensor was diagnosed and isolated. The results indicate that the system can continue to operate with at least three correct sensors.

  15. Auto-Calibration and Fault Detection and Isolation of Skewed Redundant Accelerometers in Measurement While Drilling Systems

    Directory of Open Access Journals (Sweden)

    Seyed Mohsen Seyed Moosavi

    2018-02-01

    Full Text Available The present study designed skewed redundant accelerometers for a Measurement While Drilling (MWD tool and executed auto-calibration, fault diagnosis and isolation of accelerometers in this tool. The optimal structure includes four accelerometers was selected and designed precisely in accordance with the physical shape of the existing MWD tool. A new four-accelerometer structure was designed, implemented and installed on the current system, replacing the conventional orthogonal structure. Auto-calibration operation of skewed redundant accelerometers and all combinations of three accelerometers have been done. Consequently, biases, scale factors, and misalignment factors of accelerometers have been successfully estimated. By defecting the sensors in the new optimal skewed redundant structure, the fault was detected using the proposed FDI method and the faulty sensor was diagnosed and isolated. The results indicate that the system can continue to operate with at least three correct sensors.

  16. Temperature measurement device

    International Nuclear Information System (INIS)

    Oltman, B.G.; Eckerman, K.F.; Romberg, G.P.; Prepejchal, W.

    1975-01-01

    Thermoluminescent dosimeter (TLD) material is exposed to a known amount of radiation and then exposed to the environment where temperature measurements are to be taken. After a predetermined time period, the TLD material is read in a known manner to determine the amount of radiation energy remaining in the TLD material. The difference between the energy originally stored by irradiation and that remaining after exposure to the temperature ofthe environment is a measure of the average temperature of the environment during the exposure. (U.S.)

  17. Temperature measuring device

    International Nuclear Information System (INIS)

    Brixy, H.

    1977-01-01

    The temperature measuring device is equipped with an electric resistor installed within a metal shroud tube so as to be insulated from it, the noise voltage of which resistor is fed to a measuring unit. The measuring junctions of one or two thermocouples are connected with the electric resistor and the legs of one or both thermocouples can be connected to the measuring unit by means of a switch. (orig.) [de

  18. Temperature measurement device

    International Nuclear Information System (INIS)

    Fournier, Christian; Lions, Noel.

    1975-01-01

    The present invention relates to a temperature measuring system that can be applied in particular to monitoring the temperature of the cooling liquid metal of the outlet of the core assemblies of a fast reactor. Said device combines a long hollow metallic pole, at least partially dipped into the liquid metal and constituting a first thermocouple junction between said pole, and two metallic conductors of different nature, joined at one of their ends to constitute the second thermocouple junction. Said conductors suitably insulated are arranged inside a sheath. Said sheath made of the same metals as the pole extends inside the latter and is connected with the pole through a soldered joint. Said reliable system permits an instantaneous measurement of a quantity representing the variations in the recorded temperature and a measurement of the mean surrounding temperature that can be direcly used as a reference for calibrating the first one [fr

  19. Temperature measuring device

    Energy Technology Data Exchange (ETDEWEB)

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

    1999-10-19

    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.

  20. Reactor Coolant Temperature Measurement using Ultrasonic Technology

    Energy Technology Data Exchange (ETDEWEB)

    Jung, JaeCheon [KEPCO International Nuclear graduate School, Ulsan (Korea, Republic of); Seo, YongSun; Bechue, Nicholas [Krohne Messtechnik GmbH, Duisburg (Germany)

    2016-10-15

    In NPP, the primary piping temperature is detected by four redundant RTDs (Resistance Temperature Detectors) installed 90 degrees apart on the RCS (Reactor Coolant System) piping circumferentially. Such outputs however, if applied to I and C systems would not give balanced results. The discrepancy can be explained by either thermal stratification or improper arrangement of thermo-wells and RTDs. This phenomenon has become more pronounced in the hot-leg piping than in the cold-leg. Normally, the temperature difference among channels is in the range of 1°F in Korean nuclear power Plants. Consequently, a more accurate pipe average temperate measurement technique is required. Ultrasonic methods can be used to measure average temperatures with relatively higher accuracy than RTDs because the sound wave propagation in the RCS pipe is proportional to the average temperature around pipe area. The inaccuracy of RCS temperature measurement worsens the safety margin for both DNBR and LPD. The possibility of this discrepancy has been reported with thermal stratification effect. Proposed RCS temperature measurement system based on ultrasonic technology offers a countermeasure to cope with thermal stratification effect on hot-leg piping that has been an unresolved issue in NPPs. By introducing ultrasonic technology, the average internal piping temperature can be measured with high accuracy. The inaccuracy can be decreased less than ±1℉ by this method.

  1. Ethernet redundancy

    Energy Technology Data Exchange (ETDEWEB)

    Burak, K. [Invensys Process Systems, M/S C42-2B, 33 Commercial Street, Foxboro, MA 02035 (United States)

    2006-07-01

    We describe the Ethernet systems and their evolution: LAN Segmentation, DUAL networks, network loops, network redundancy and redundant network access. Ethernet (IEEE 802.3) is an open standard with no licensing fees and its specifications are freely available. As a result, it is the most popular data link protocol in use. It is important that the network be redundant and standard Ethernet protocols like RSTP (IEEE 802.1w) provide the fast network fault detection and recovery times that is required today. As Ethernet does continue to evolve, network redundancy is and will be a mixture of technology standards. So it is very important that both end-stations and networking devices be Ethernet (IEEE 802.3) compliant. Then when new technologies, such as the IEEE 802.1aq Shortest Path Bridging protocol, come to market they can be easily deployed in the network without worry.

  2. Ethernet redundancy

    International Nuclear Information System (INIS)

    Burak, K.

    2006-01-01

    We describe the Ethernet systems and their evolution: LAN Segmentation, DUAL networks, network loops, network redundancy and redundant network access. Ethernet (IEEE 802.3) is an open standard with no licensing fees and its specifications are freely available. As a result, it is the most popular data link protocol in use. It is important that the network be redundant and standard Ethernet protocols like RSTP (IEEE 802.1w) provide the fast network fault detection and recovery times that is required today. As Ethernet does continue to evolve, network redundancy is and will be a mixture of technology standards. So it is very important that both end-stations and networking devices be Ethernet (IEEE 802.3) compliant. Then when new technologies, such as the IEEE 802.1aq Shortest Path Bridging protocol, come to market they can be easily deployed in the network without worry

  3. Temperature measurements by thermocouples

    International Nuclear Information System (INIS)

    Liermann, J.

    1975-01-01

    The measurement of a temperature (whatever the type of transducer used) raises three problems: the choice of transducer; where it should be placed; how it should be fixed and protected. These are the three main points examined, after a brief description of the most commonly used thermocouples [fr

  4. Redundant and fault-tolerant algorithms for real-time measurement and control systems for weapon equipment.

    Science.gov (United States)

    Li, Dan; Hu, Xiaoguang

    2017-03-01

    Because of the high availability requirements from weapon equipment, an in-depth study has been conducted on the real-time fault-tolerance of the widely applied Compact PCI (CPCI) bus measurement and control system. A redundancy design method that uses heartbeat detection to connect the primary and alternate devices has been developed. To address the low successful execution rate and relatively large waste of time slices in the primary version of the task software, an improved algorithm for real-time fault-tolerant scheduling is proposed based on the Basic Checking available time Elimination idle time (BCE) algorithm, applying a single-neuron self-adaptive proportion sum differential (PSD) controller. The experimental validation results indicate that this system has excellent redundancy and fault-tolerance, and the newly developed method can effectively improve the system availability. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  5. Temperature measurement in the sea

    Digital Repository Service at National Institute of Oceanography (India)

    Krishnamacharyulu, R.J.; Rao, L.V.G.

    The importance of measuring sea temperature is explained and the various methods employed for this purpose are reviewed. Instruments used for spot measurement of water temperature at the sea surface and at discrete depths (bucket thermometer...

  6. Temperature measurement with neutrons

    International Nuclear Information System (INIS)

    Bizard, G.; Durand, D.; Lecolley, J.F.; Lefebvres, F.; Marques, M.; Peter, J.; Tamain, B.

    1998-01-01

    The results presented in this report were obtained from the information provided by charged products. Another alternative consists in detecting the neutrons abundantly emitted particularly by heavy nuclei. The residue channel was studied in the 40 Ar + 197 Au at 60 MeV/nucleon by means of the neutron multidetector DEMON. The evolution of the multiplicity of neutrons emitted backwards in the framework of the heavy nucleus forwardly detected as a function of the residue velocity by a silicon detector, placed at 8 degrees and at 24.5 cm from target, agrees with the expected results i.e. an increase with the residue velocity hence with the collision violence. For the same detector the first measurements show similarly a linear increase of the apparent temperature of 4.0 to around 6.5 MeV for residue velocities varying from 0.5 to 1.3 cm/ns and masses ranging from 140 to 160 uma. This first results of the analysis show therefore a good behaviour of the assembly and especially of the couple DeMoN-SyReP

  7. Neutron ion temperature measurement

    International Nuclear Information System (INIS)

    Strachan, J.D.; Hendel, H.W.; Lovberg, J.; Nieschmidt, E.B.

    1986-11-01

    One important use of fusion product diagnostics is in the determination of the deuterium ion temperature from the magnitude of the 2.5 MeV d(d,n) 3 He neutron emission. The detectors, calibration methods, and limitations of this technique are reviewed here with emphasis on procedures used at PPPL. In most tokamaks, the ion temperature deduced from neutrons is in reasonable agreement with the ion temperature deduced by other techniques

  8. A polar-region-adaptable systematic bias collaborative measurement method for shipboard redundant rotational inertial navigation systems

    Science.gov (United States)

    Wang, Lin; Wu, Wenqi; Wei, Guo; Lian, Junxiang; Yu, Ruihang

    2018-05-01

    The shipboard redundant rotational inertial navigation system (RINS) configuration, including a dual-axis RINS and a single-axis RINS, can satisfy the demand of marine INSs of especially high reliability as well as achieving trade-off between position accuracy and cost. Generally, the dual-axis RINS is the master INS, and the single-axis RINS is the hot backup INS for high reliability purposes. An integrity monitoring system performs a fault detection function to ensure sailing safety. However, improving the accuracy of the backup INS in case of master INS failure has not been given enough attention. Without the aid of any external information, a systematic bias collaborative measurement method based on an augmented Kalman filter is proposed for the redundant RINSs. Estimates of inertial sensor biases can be used by the built-in integrity monitoring system to monitor the RINS running condition. On the other hand, a position error prediction model is designed for the single-axis RINS to estimate the systematic error caused by its azimuth gyro bias. After position error compensation, the position information provided by the single-axis RINS still remains highly accurate, even if the integrity monitoring system detects a dual-axis RINS fault. Moreover, use of a grid frame as a navigation frame makes the proposed method applicable in any area, including the polar regions. Semi-physical simulation and experiments including sea trials verify the validity of the method.

  9. A survey of temperature measurement

    International Nuclear Information System (INIS)

    Saltvold, J.R.

    1976-03-01

    Many different techniques for measuring temperature have been surveyed and are discussed. The concept of temperature and the physical phenomena used in temperature measurement are also discussed. Extensive tables are presented in which the range and accuracy of the various techniques and other related data are included. (author)

  10. An Adaptive Low-Cost INS/GNSS Tightly-Coupled Integration Architecture Based on Redundant Measurement Noise Covariance Estimation.

    Science.gov (United States)

    Li, Zheng; Zhang, Hai; Zhou, Qifan; Che, Huan

    2017-09-05

    The main objective of the introduced study is to design an adaptive Inertial Navigation System/Global Navigation Satellite System (INS/GNSS) tightly-coupled integration system that can provide more reliable navigation solutions by making full use of an adaptive Kalman filter (AKF) and satellite selection algorithm. To achieve this goal, we develop a novel redundant measurement noise covariance estimation (RMNCE) theorem, which adaptively estimates measurement noise properties by analyzing the difference sequences of system measurements. The proposed RMNCE approach is then applied to design both a modified weighted satellite selection algorithm and a type of adaptive unscented Kalman filter (UKF) to improve the performance of the tightly-coupled integration system. In addition, an adaptive measurement noise covariance expanding algorithm is developed to mitigate outliers when facing heavy multipath and other harsh situations. Both semi-physical simulation and field experiments were conducted to evaluate the performance of the proposed architecture and were compared with state-of-the-art algorithms. The results validate that the RMNCE provides a significant improvement in the measurement noise covariance estimation and the proposed architecture can improve the accuracy and reliability of the INS/GNSS tightly-coupled systems. The proposed architecture can effectively limit positioning errors under conditions of poor GNSS measurement quality and outperforms all the compared schemes.

  11. Temperature Measurements in the Magnetic Measurement Facility

    Energy Technology Data Exchange (ETDEWEB)

    Wolf, Zachary

    2010-12-13

    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

  12. Radiometric temperature measurements fundamentals

    CERN Document Server

    Zhang, Zhuomin M; Machin, Graham

    2009-01-01

    This book describes the theory of radiation thermometry, both at a primary level and for a variety of applications, such as in the materials processing industries and remote sensing. This book is written for those who will apply radiation thermometry in industrial practice; use radiation thermometers for scientific research; the radiation thermometry specialist in a national measurement institute; developers of radiation thermometers who are working to innovate products for instrument manufacturers, and developers of non-contact thermometry methods to address challenging thermometry problems.

  13. Temperature radiation measuring equipment. Temperaturstrahlungsmessgeraet

    Energy Technology Data Exchange (ETDEWEB)

    Lotzer, W

    1981-01-22

    The invention is concerned with a temperature radiation measuring equipment for non-contact temperature measurement by the light intensity variation method, with a photoelectric resistance as the measuring element. By having a circuit with a transistor, the 'dark resistance' occurring in the course of time is compensated for and thus gives a genuine reading (ie. the voltage drop across the photoelectric resistance remains constant).

  14. Improving the Performance of MEMS GYROS via Redundant Measurements: Theory and Experiments

    Science.gov (United States)

    2014-12-01

    PC via a USB-micro-USB connector ................................46 Figure 28 Arduino serial port monitor displaying the default menu screen for the...done by specific pieces of hardware. 12*9-DOF Sensor Array Computer Wired / Wireless Router Arduino Software Upload Displayed on Host PC Real...a total of nine axes of measurement on the IMU. The integration software included on the sensors Arduino board incorporates data from all nine axes

  15. Temperature measurements in thermonuclear plasmas

    International Nuclear Information System (INIS)

    Breton, D.

    1958-01-01

    The temperatures needed to produce thermonuclear reactions are of the order of several million degrees Kelvin. Devising methods for measuring such temperatures has been the subject of research in many countries. In order to present the problem clearly and to demonstrate its importance, the author reviews the various conditions which must be fulfilled in order that reactions may be qualified as thermonuclear. The relationship between the temperature and the cross-section of the reactions is studied, and it is shown that the notion of temperature in the plasmas is complex, which leads to a consideration of the temperature of the ions and that of the electrons. None of the methods for the temperature measurements is completely satisfactory because of the hypotheses which must be made, and which are seldom fulfilled during high-intensity discharges in the plasmas. In practice it is necessary to use several methods simultaneously. (author) [fr

  16. The Kelvin and Temperature Measurements

    Science.gov (United States)

    Mangum, B. W.; Furukawa, G. T.; Kreider, K. G.; Meyer, C. W.; Ripple, D. C.; Strouse, G. F.; Tew, W. L.; Moldover, M. R.; Johnson, B. Carol; Yoon, H. W.; Gibson, C. E.; Saunders, R. D.

    2001-01-01

    The International Temperature Scale of 1990 (ITS-90) is defined from 0.65 K upwards to the highest temperature measurable by spectral radiation thermometry, the radiation thermometry being based on the Planck radiation law. When it was developed, the ITS-90 represented thermodynamic temperatures as closely as possible. Part I of this paper describes the realization of contact thermometry up to 1234.93 K, the temperature range in which the ITS-90 is defined in terms of calibration of thermometers at 15 fixed points and vapor pressure/temperature relations which are phase equilibrium states of pure substances. The realization is accomplished by using fixed-point devices, containing samples of the highest available purity, and suitable temperature-controlled environments. All components are constructed to achieve the defining equilibrium states of the samples for the calibration of thermometers. The high quality of the temperature realization and measurements is well documented. Various research efforts are described, including research to improve the uncertainty in thermodynamic temperatures by measuring the velocity of sound in gas up to 800 K, research in applying noise thermometry techniques, and research on thermocouples. Thermometer calibration services and high-purity samples and devices suitable for “on-site” thermometer calibration that are available to the thermometry community are described. Part II of the paper describes the realization of temperature above 1234.93 K for which the ITS-90 is defined in terms of the calibration of spectroradiometers using reference blackbody sources that are at the temperature of the equilibrium liquid-solid phase transition of pure silver, gold, or copper. The realization of temperature from absolute spectral or total radiometry over the temperature range from about 60 K to 3000 K is also described. The dissemination of the temperature scale using radiation thermometry from NIST to the customer is achieved by

  17. Michelson interferometer for measuring temperature

    OpenAIRE

    Xie, Dong; Xu, Chunling; wang, Anmin

    2016-01-01

    We investigate that temperature can be measured by a modified Michelson interferometer, where at least one reflected mirror is replaced by a thermalized sample. Both of two mirrors replaced by the corresponding two thermalized samples can help to approximatively improve the resolution of temperature up to twice than only one mirror replaced by a thermalized sample. For further improving the precision, a nonlinear medium can be employed. The Michelson interferometer is embedded in a gas displa...

  18. Michelson interferometer for measuring temperature

    Science.gov (United States)

    Xie, Dong; Xu, Chunling; Wang, An Min

    2017-09-01

    We investigate that temperature can be measured by a modified Michelson interferometer, where at least one reflected mirror is replaced by a thermalized sample. Both of two mirrors replaced by the corresponding two thermalized samples can help to approximatively improve the resolution of temperature up to twice than only one mirror replaced by a thermalized sample. For further improving the precision, a nonlinear medium can be employed. The Michelson interferometer is embedded in a gas displaying Kerr nonlinearity. We obtain the analytical equations and numerically calculate the precision with parameters within the reach of current technology, proving that the precision of temperature can be greatly enhanced by using a nonlinear medium. Our results show that one can create an accurate thermometer by measuring the photons in the Michelson interferometer, with no need to directly measure the population of thermalized sample.

  19. Laser Pyrometer For Spot Temperature Measurements

    Science.gov (United States)

    Elleman, D. D.; Allen, J. L.; Lee, M. C.

    1988-01-01

    Laser pyrometer makes temperature map by scanning measuring spot across target. Scanning laser pyrometer passively measures radiation emitted by scanned spot on target and calibrated by similar passive measurement on blackbody of known temperature. Laser beam turned on for active measurements of reflectances of target spot and reflectance standard. From measurements, temperature of target spot inferred. Pyrometer useful for non-contact measurement of temperature distributions in processing of materials.

  20. Construct redundancy within the Five-Factor Model as measured by the NEO PI-R: Implications for emotional intelligence and incremental coherence

    Directory of Open Access Journals (Sweden)

    GILLES E. GIGNAC

    2009-03-01

    Full Text Available Self-report measures of emotional intelligence (EI have been criticized for not being associated with unique validity, independently of comprehensive measures of personality such as the NEO PI-R. In this investigation, the issue of unique validity was re-directed at personality as measured by the facets of the NEO PI-R. Specifically, based on three samples, the personality facet of Depression within the NEO PI-R was found to be so substantially predicted by ten other NEO PI-R facets as to suggest construct redundancy within the NEO PI-R (i.e., R = .93, R = .99, R = .96. Because mixed-models of EI tend to be associated with clearer construct boundaries than personality, it is suggested that EI may be associated with some scientific utility (i.e., ‘incremental coherence’, even in the total absence of any empirically demonstrable unique validity.

  1. Apparatus Would Measure Temperatures Of Ball Bearings

    Science.gov (United States)

    Gibson, John C.; Fredricks, Thomas H.

    1995-01-01

    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.

  2. Measuring Poisson Ratios at Low Temperatures

    Science.gov (United States)

    Boozon, R. S.; Shepic, J. A.

    1987-01-01

    Simple extensometer ring measures bulges of specimens in compression. New method of measuring Poisson's ratio used on brittle ceramic materials at cryogenic temperatures. Extensometer ring encircles cylindrical specimen. Four strain gauges connected in fully active Wheatstone bridge self-temperature-compensating. Used at temperatures as low as liquid helium.

  3. Temperature measurement in nuclear environment

    International Nuclear Information System (INIS)

    Degas, P.

    1986-12-01

    Some criterions, that the used sensors have to follow, are given together with the conditions they may encountered. They may be used in irradiation or safety test devices, in experiments concerning mock-up or plant element, or even in nuclear plants themselves. The most suitable sensor type are mentioned, with their characteristics and their fiability. Two use examples of temperature probes are given, chosen to illustrate two sensor types: thermocouples in Superphenix-1 and platinum resistance probes in research reactor Orphee [fr

  4. Field of Temperature Measurement by Virtual Instrumentation

    Directory of Open Access Journals (Sweden)

    Libor HARGAŠ

    2009-01-01

    Full Text Available This paper introduces about temperature determination for given dot of picture through image analysis. Heat transfer is the transition of thermal energy from a heated item to a cooler item. Main method of measurement of temperature in image is Pattern Matching, color scale detection and model detection. We can measure temperature dependency at time for selected point of thermo vision images. This measurement gives idea about the heat transfer at time dependences.

  5. Temperature standards, what and where: resources for effective temperature measurements

    International Nuclear Information System (INIS)

    Johnston, W.W. Jr.

    1982-01-01

    Many standards have been published to describe devices, methods, and other topics. How they are developed and by whom are briefly described, and an attempt is made to extract most of those relating to temperature measurements. A directory of temperature standards and their sources is provided

  6. Temperature measurement systems in wearable electronics

    Science.gov (United States)

    Walczak, S.; Gołebiowski, J.

    2014-08-01

    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.

  7. Estimation of complete temperature fields from measured temperatures

    International Nuclear Information System (INIS)

    Clegg, S.T.; Roemer, R.B.

    1984-01-01

    In hyperthermia treatments, it is desirable to be able to predict complete tissue temperature fields from sampled temperatures taken at a few locations. This is a difficult problem in hyperthermia treatments since the tissue blood perfusion is unknown. An initial attempt to do this automatically using unconstrained optimization techniques to minimize the differences between steady state temperatures measured during a treatment and temperatures (at the same locations) predicted from treatment simulations has been previously reported. A second technique using transient temperatures following a step decrease in power has been developed. This technique, which appears to be able to better predict complete temperature fields is presented and both it and the steady state technique are applied to data from both simulated and experimental hyperthermia treatments. The results of applying the two techniques are compared for one-dimensional situations. One particularly important problem which the transient technique can solve (and the steady state technique does not seem to be able to do as well) is that of predicting the complete temperature field in situations where the true maximum and/or minimum temperatures present are not measured by the available instrumentation

  8. Designing an accurate system for temperature measurements

    Directory of Open Access Journals (Sweden)

    Kochan Orest

    2017-01-01

    Full Text Available The method of compensation of changes in temperature field along the legs of inhomogeneous thermocouple, which measures a temperature of an object, is considered in this paper. This compensation is achieved by stabilization of the temperature field along the thermocouple. Such stabilization does not allow the error due to acquired thermoelectric inhomogeneity to manifest itself. There is also proposed the design of the furnace to stabilize temperature field along the legs of the thermocouple which measures the temperature of an object. This furnace is not integrated with the thermocouple mentioned above, therefore it is possible to replace this thermocouple with a new one when it get its legs considerably inhomogeneous.. There is designed the two loop measuring system with the ability of error correction which can use simultaneously a usual thermocouple as well as a thermocouple with controlled profile of temperature field. The latter can be used as a reference sensor for the former.

  9. Surface temperature measurement with radioactive kryptonates

    International Nuclear Information System (INIS)

    Pruzinec, J.; Piatrik, M.

    1976-01-01

    The preparation and use of radioactive kryptonates is described for measuring surface temperatures within the region of 45 to 70 degC. Two samples each were prepared of kryptonated beechwood and hydroquinone on a paper carrier. One sample served as the standard which during the experiment was placed in a thermostat at a constant temperature of 45 degC. The second sample was placed in another thermostat where the temperature changed from 45 to 70 degC. Both samples were in the thermostat for 30 mins. The temperature was raised in steps of 2.5 degC and the time of measurement was constant in both samples. The dependences are given of the drop in activity on temperature for both types of samples. The difference was determined of the drop in activity between the standard and the second sample and the relation for measuring the temperature of the sample was determined therefrom. (J.B.)

  10. Palpebral redundancy from hypothyroidism.

    Science.gov (United States)

    Wortsman, J; Wavak, P

    1980-01-01

    A patient is described with disabling palpebral edema. Primary hypothyroidism had been previously diagnosed and treated. Testing of thyroid function revealed persistence of the hypothyroidism. Treatment with L-thyroxine produced normalization of the biochemical parameters and resolution of palpebral edema. The search for hypothyrodism in patients with palpebral redundancy is emphasized.

  11. Dynamic temperature measurements with embedded optical sensors.

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-10-01

    This report summarizes LDRD project number 151365, \\Dynamic Temperature Measurements with Embedded Optical Sensors". 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.

  12. Measurements of temperature dependence of 'localized susceptibility'

    CERN Document Server

    Shiozawa, H; Ishii, H; Takayama, Y; Obu, K; Muro, T; Saitoh, Y; Matsuda, T D; Sugawara, H; Sato, H

    2003-01-01

    The magnetic susceptibility of some rare-earth compounds is estimated by measuring magnetic circular dichroism (MCD) of rare-earth 3d-4f absorption spectra. The temperature dependence of the magnetic susceptibility obtained by the MCD measurement is remarkably different from the bulk susceptibility in most samples, which is attributed to the strong site selectivity of the core MCD measurement.

  13. Temperature measurement with industrial color camera devices

    Science.gov (United States)

    Schmidradler, Dieter J.; Berndorfer, Thomas; van Dyck, Walter; Pretschuh, Juergen

    1999-05-01

    This paper discusses color camera based temperature measurement. Usually, visual imaging and infrared image sensing are treated as two separate disciplines. We will show, that a well selected color camera device might be a cheaper, more robust and more sophisticated solution for optical temperature measurement in several cases. Herein, only implementation fragments and important restrictions for the sensing element will be discussed. Our aim is to draw the readers attention to the use of visual image sensors for measuring thermal radiation and temperature and to give reasons for the need of improved technologies for infrared camera devices. With AVL-List, our partner of industry, we successfully used the proposed sensor to perform temperature measurement for flames inside the combustion chamber of diesel engines which finally led to the presented insights.

  14. General temperature field measurement by digital holography

    Czech Academy of Sciences Publication Activity Database

    Doleček, Roman; Psota, Pavel; Lédl, Vít; Vít, Tomáš; Václavík, Jan; Kopecký, V.

    2013-01-01

    Roč. 52, č. 1 (2013), A319-A325 ISSN 1559-128X Institutional support: RVO:61389021 Keywords : digital holography * temperature field measurement * tomography Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.649, year: 2013

  15. Noise thermometry - a new temperature measuring method

    International Nuclear Information System (INIS)

    Brixy, H.; Hecker, R.; Rittinghaus, K.F.

    1975-01-01

    The thermal Johnson-Niquist noise is the basis of noise thermometry. This temperature measuring method is, e.g., of interest insofar as the noise thermometer gives absolute values as a primary thermometer and is in principle extensively independent of environmental influences and material properties. The resistance values of the measuring probe are about 10 Ohm to a few kOhm. The demands of electronics are high, the self-noise of the measuring apparatus must be as small as possible; a comparative measuring method is advantageous. 1 to 2,500 K are given as a possible temperature range. An accuracy of 0.1% could be achieved in laboratory measurements. Temperature measurements to be used in operation in a few nuclear reactors are mentioned. (HP/LH) [de

  16. Wideband filter radiometers for blackbody temperature measurements

    Science.gov (United States)

    Boivin, L. P.; Bamber, C.; Gaertner, A. A.; Gerson, R. K.; Woods, D. J.; Woolliams, E. R.

    2010-10-01

    The use of high-temperature blackbody (HTBB) radiators to realize primary spectral irradiance scales requires that the operating temperature of the HTBB be accurately determined. We have developed five filter radiometers (FRs) to measure the temperature of the National Research Council of Canada's HTBB. The FRs are designed to minimize sensitivity to ambient temperature fluctuations. They incorporate air-spaced colored glass filters and a Si photodiode detector that are housed in a cell whose temperature is controlled to ±0.1°C by means of annular thermoelectric elements at the front and rear of the cell. These wideband filter radiometers operate in four different wavelength bands. The spectral responsivity measurements were performed in an underfill geometry for a power-mode calibration that is traceable to NRC's cryogenic radiometer. The spectral temperature sensitivity of each of these FRs has been measured. The apertures for these FRs were cold-formed by swaging machine-cut apertures onto precision dowel pins. A description of the filter radiometer design, fabrication and testing, together with a detailed uncertainty analysis, is presented. We derive the equations that relate the spectral irradiance measured by the FRs to the spectral radiance and temperature of the HTBB, and deal specifically with the change of index of refraction over the path of the radiation from the interior of the HTBB to the FRs. We believe these equations are more accurate than recently published derivations. Our measurements of the operating temperature of our HTBB working at temperatures near 2500 K, 2700 K and 2900 K, together with measurements using a pyrometer, show agreement between the five filter radiometers and with the pyrometer to within the estimated uncertainties.

  17. Empirical Temperature Measurement in Protoplanetary Disks

    Science.gov (United States)

    Weaver, Erik; Isella, Andrea; Boehler, Yann

    2018-02-01

    The accurate measurement of temperature in protoplanetary disks is critical to understanding many key features of disk evolution and planet formation, from disk chemistry and dynamics, to planetesimal formation. This paper explores the techniques available to determine temperatures from observations of single, optically thick molecular emission lines. Specific attention is given to issues such as the inclusion of optically thin emission, problems resulting from continuum subtraction, and complications of real observations. Effort is also made to detail the exact nature and morphology of the region emitting a given line. To properly study and quantify these effects, this paper considers a range of disk models, from simple pedagogical models to very detailed models including full radiative transfer. Finally, we show how the use of the wrong methods can lead to potentially severe misinterpretations of data, leading to incorrect measurements of disk temperature profiles. We show that the best way to estimate the temperature of emitting gas is to analyze the line peak emission map without subtracting continuum emission. Continuum subtraction, which is commonly applied to observations of line emission, systematically leads to underestimation of the gas temperature. We further show that once observational effects such as beam dilution and noise are accounted for, the line brightness temperature derived from the peak emission is reliably within 10%–15% of the physical temperature of the emitting region, assuming optically thick emission. The methodology described in this paper will be applied in future works to constrain the temperature, and related physical quantities, in protoplanetary disks observed with ALMA.

  18. Assessment of body temperature measurement options.

    Science.gov (United States)

    Sund-Levander, Märtha; Grodzinsky, Ewa

    Assessment of body temperature is important for decisions in nursing care, medical diagnosis, treatment and the need of laboratory tests. The definition of normal body temperature as 37°C was established in the middle of the 19th century. Since then the technical design and the accuracy of thermometers has been much improved. Knowledge of physical influence on the individual body temperature, such as thermoregulation and hormones, are still not taken into consideration in body temperature assessment. It is time for a change; the unadjusted mode should be used, without adjusting to another site and the same site of measurement should be used as far as possible. Peripheral sites, such as the axillary and the forehead site, are not recommended as an assessment of core body temperature in adults. Frail elderly individuals might have a low normal body temperature and therefore be at risk of being assessed as non-febrile. As the ear site is close to the hypothalamus and quickly responds to changes in the set point temperature, it is a preferable and recommendable site for measurement of body temperature.

  19. Temperature measurement of tin under shock compression

    International Nuclear Information System (INIS)

    Hereil, Pierre-Louis; Mabire, Catherine

    2002-01-01

    The results of pyrometric measurements performed at the interface of a tin target with a LiF window material are presented for stresses ranging from 38 to 55 GPa. The purpose of the study is to analyze the part of the interface in the temperature measurement by a multi-channel pyrometric device. The results show that the glue used at target/window interface remains transparent under shock. The values of temperature measured at the tin/LiF interface are consistent with the behavior of tin under shock

  20. Temperature measurement in the flowing medium

    Directory of Open Access Journals (Sweden)

    Sedlák Kamil

    2018-01-01

    Full Text Available The article deals with a brief description of methods of temperature measurements in a flowing water steam. Attention is paid to the measurement of pseudo static temperature by a single sealed thermocouple entering the flowing liquid through the flown-by wall. Then three types of probes for stagnation temperature measurement are shown, whose properties were tested using CFD calculations. The aim was to design a probe of stagnation parameters of described properties which can be used for measuring flow parameters in a real steam turbine. An important factor influencing the construction is not only the safe manipulation of the probe when inserting and removing it from the machine in operation, but also the possibility to traverse the probe along the blade length.

  1. Temperature measurements of shock-compressed deuterium

    International Nuclear Information System (INIS)

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

    1994-11-01

    The authors measured the temperatures of single and double-shocked D 2 and H 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

  2. Laboratory setup for temperature and humidity measurements

    CERN Document Server

    Eimre, Kristjan

    2015-01-01

    In active particle detectors, the temperature and humidity conditions must be under constant monitoring and control, as even small deviations from the norm cause changes to detector characteristics and result in a loss of precision. To monitor the temperature and humidity, different kinds of sensors are used, which must be calibrated beforehand to ensure their accuracy. To calibrate the large number of sensors that are needed for the particle detectors and other laboratory work, a calibration system is needed. The purpose of the current work was to develop a laboratory setup for temperature and humidity sensor measurements and calibration.

  3. Cutting temperature measurement and material machinability

    Directory of Open Access Journals (Sweden)

    Nedić Bogdan P.

    2014-01-01

    Full Text Available Cutting temperature is very important parameter of cutting process. Around 90% of heat generated during cutting process is then away by sawdust, and the rest is transferred to the tool and workpiece. In this research cutting temperature was measured with artificial thermocouples and question of investigation of metal machinability from aspect of cutting temperature was analyzed. For investigation of material machinability during turning artificial thermocouple was placed just below the cutting top of insert, and for drilling thermocouples were placed through screw holes on the face surface. In this way was obtained simple, reliable, economic and accurate method for investigation of cutting machinability.

  4. High temperature measurement by noise thermometry

    International Nuclear Information System (INIS)

    Decreton, M.C.

    1982-06-01

    Noise thermometry has received a lot of attention for measurements of temperatures in the high range around 1000-2000 deg. K. For these measurements, laboratory type experiments have been mostly performed. These have shown the interest of the technique when long term stability, high precision and insensibility to external conditions are concerned. This is particularly true for measurements in nuclear reactors where important drifts due to irradiation effects are experienced with other measurement techniques, as thermocouple for instance. Industrial noise thermometer experiments have not been performed extensively up to now. The subject of the present study is the development of a 1800 deg. K noise thermometer for nuclear applications. The measurement method is based on a generalized noise power approach. The rms noise voltage (Vsub(s)) and noise current (Isub(s)) are successively measured on the resistive sensor. The same quantities are also measured on a dummy short circuited probe (Vsub(d) and Isub(d)). The temperature is then deduced from these measured values by the following formula: cTsub(s) = (Vsub(s) 2 - Vsub(d) 2 )(Vsub(s)/Isub(s) - Vsub(d)/Isub(d)) - 1 , where c is a constant and Tsub(s) the absolute temperature of the sensor. This approach has the particular advantage of greatly reducing the sensibility to environmental perturbations on the leads and to the influence of amplifier noise sources. It also eliminates the necessity of resistance measurement and keeps the electronic circuits as simple as possible

  5. Temperature measurements at the LMFBR core outlet

    International Nuclear Information System (INIS)

    Argous, J.P.; Berger, R.; Casejuane, R.; Fournier, C.; Girard, J.P.

    1980-04-01

    Over the last few years the temperature sensors used to measure the subassembly outlet temperature in French designed LMFBRs have been modified, basically in an effort to reduce the dispersion of the chromel-alumel thermocouple time constant, and to extend the frequency spectrum of the measurement signals by adding a steel electrode to from a stainless steel-sodium thermocouple. The result of this evolution is the temperature probe immersed in sodium which will be used in the SUPER PHENIX reactor. This paper describes the tests already completed or in progress on this probe. It also presents measurement data on the two basic probe parameters: the thermoelectric power of the stainless steel-sodium thermocouple and the time constant of the chromel-alumel thermocouple

  6. Slot Antenna for Wireless Temperature Measurement Systems

    DEFF Research Database (Denmark)

    Acar, Öncel; Jakobsen, Kaj Bjarne

    2016-01-01

    This paper presents a novel clover-slot antenna for a surface-acoustic-wave sensor based wireless temperature measurement system. The slot is described by a parametric locus curve that has the shape of a clover. The antenna is operated at high temperatures, in rough environments, and has a 43......% fractional bandwidth at the 2.4 GHz ISM-band. The slot antenna has been optimized for excitation by a passive chip soldered onto it. Measurement results are compared with simulation results and show good agreements....

  7. Ion temperature measurements in the Maryland Spheromak

    International Nuclear Information System (INIS)

    Gauvreau, J.L.

    1992-01-01

    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 μs, a conversion of mass flow kinetic energy into ion temperature could take place due to viscosity

  8. Measurement of rotational temperature at Kolhapur, India

    Directory of Open Access Journals (Sweden)

    G. K. Mukherjee

    2004-09-01

    Full Text Available Measurements of the hydroxyl rotational temperature for the (8,3 Meinel band have been reported from the observations of the ratio of the relative intensities of P1(2 and P1(4 lines of the OH(8,3 band at Kolhapur (16.8° N, 74.2° E, dip lat. 10.6° N in India during the period 1 November 2002-29 April 2003 using tilting-filter photometers. Mean values of rotational temperature have been computed for 60 nights. The monthly mean value of temperature lies in the range 194(±11-208(±18K. The mean rotational temperature obtained from all the measurements was found to be 202±15K. The results agree with other low-latitude measurements of rotational temperature using photometric airglow techniques. Quasi-periodic fluctuations with a period of about one to two hours have been prominent on many nights. Furthermore, the results show the general agreement between observations and model (MSIS-86 predictions.

  9. A control method for manipulators with redundancy

    International Nuclear Information System (INIS)

    Furusho, Junji; Usui, Hiroyuki

    1989-01-01

    Redundant manipulators have more ability than nonredundant ones in many aspects such as avoiding obstacles, avoiding singular states, etc. In this paper, a control algorithm for redundant manipulators working under the circumstance in the presence of obstacles is presented. First, the measure of manipulability for robot manipulators under obstacle circumstances is defined. Then, the control algorithm for the obstacle avoidance is derived by using this measure of manipulability. The obstacle avoidance and the maintenance of good posture are simultaneously achieved by this algorithm. Lastly, an experiment and simulation results using an eight degree of freedom manipulator are shown. (author)

  10. Temperature measurements in ZT-40M

    International Nuclear Information System (INIS)

    Little, E.M.; Haberstich, A.; Thomas, K.S.; Watt, R.G.

    1983-01-01

    Electron temperatures derived from Thomson scattering and ultrasoft x-ray (USXR) measurements taken before and after machine modifications are compared for ZT-40M. Modifications were made to the magnetic field windings to reduce field errors and the joints in the aluminum shell were coated with joint compound to reduce resistance and make all joints electrically uniform. These modifications resulted in increased plasma lifetime in ZT-40M from less than 10 ms to over 20 ms. Thomson scattering measurements were made with a single-point Thomson scattering apparatus. The scattered spectrum is collected by a three-grating spectrometer. The soft x rays are collected by a two-foil differential transmission system whose foil ratios may be easily varied. Before modifications the Thomson scattering and soft x-ray temperatures agreed up until 3 to 4 ms into the discharge. After this time the Thomson scattering temperature decreased slowly while the soft x-ray ''temperature'' increased rapidly. field errors resulted in Thomson scattering and USXR ''temperature'' time histories remaining fairly flat out to 10 to 11 ms, but introduced a small discrepancy (about 50 eV) in the absolute value of the temperatures. This change may be due either to the change in foil thickness used or to changes in radial temperature profiles. Profile changes may have been caused by the addition of four poloidal limiters or improvements to the magnetic field topology. After modifications the temperatures from both Thomson scattering and USXR were lower and the plasma density was higher. This is probably a result of the lower plasma-wall interaction with the new configuration

  11. Two methods to measure granular gas temperature

    Science.gov (United States)

    Chastaing, J.-Y.; Géminard, J.-C.; Naert, A.

    2017-07-01

    Grains are vibrated so as to achieve a granular gas, here regarded as an archetype of a dissipative non equilibrium steady state (NESS). We report on two distinct and concordant experimental measures of the system effective temperature. To do so, a blade fastened to the shaft of a small DC-motor, immersed in the grains, behaves as a driven 1D Brownian rotator, which is used as both actuator and sensor simultaneously. On the one hand, the Gallavotti-Cohen fluctuation theorem, which involves a measure of the asymmetry of the energy exchanges between the rotator and the NESS reservoir, provides a first effective temperature. On the other hand, the fluctuation-dissipation theorem, which involves the relation between the spontaneous fluctuations and the response to a weak perturbation, defines a second, independent, effective temperature. Both methods, even though they are based on drastically different ideas, give nicely concordant results.

  12. Measurement of very rapidly variable temperatures

    International Nuclear Information System (INIS)

    Elberg, S.; Mathonnet, P.

    1974-01-01

    Bibliographical research and visits to laboratories were undertaken in order to survey the different techniques used to measure rapidly variable temperatures, specifying the limits in maximum temperature and variation rate (time constant). On the basis of the bibliographical study these techniques were classified in three categories according to the physical meaning of their response time. Extension of the bibliographical research to methods using fast temperature variation measurement techniques and visits to research and industrial laboratories gave in an idea of the problems raised by the application of these methods. The use of these techniques in fields other than those for which they were developed can sometimes be awkward in the case of thermometric probe devices where the time constant cannot generally be specified [fr

  13. NMR measurement of bitumen at different temperatures.

    Science.gov (United States)

    Yang, Zheng; Hirasaki, George J

    2008-06-01

    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 (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 (index (HI), fluid content and viscosity were evaluated by using corrected T2.

  14. Measurement of low-temperature specific heat

    International Nuclear Information System (INIS)

    Stewart, G.R.

    1983-01-01

    The measurement of low-temperature specific heat (LTSH) (0.1 K< T<60 K) has seen a number of breakthroughs both in design concepts and instrumentation in the last 15 years: particularly in small sample calorimetry. This review attempts to provide an overview of both large and small sample calorimetry techniques at temperatures below 60 K, with sufficient references to enable more detailed study. A comprehensive review is made of the most reliable measurements of the LTSH of 84 of the elements to illustrate briefly some of the problems of measurements and analysis, as well as to provide additional references. More detail is devoted to three special areas of low-temperature calorimetry that have seen rapid development recently: (1) measurement of the specific heat of highly radioactive samples, (2) measurement of the specific heat of materials in high magnetic fields (18 T), and (3) measurement of the specific heat of very small (100 μg) samples. The review ends with a brief discussion of the frontier research currently underway on microcalorimetry for nanogram sample weights

  15. Measuring Thermal Conductivity at LH2 Temperatures

    Science.gov (United States)

    Selvidge, Shawn; Watwood, Michael C.

    2004-01-01

    For many years, the National Institute of Standards and Technology (NIST) produced reference materials for materials testing. One such reference material was intended for use with a guarded hot plate apparatus designed to meet the requirements of ASTM C177-97, "Standard Test Method for Steady-State Heat Flux Measurements and Thermal Transmission Properties by Means of the Guarded-Hot-Plate Apparatus." This apparatus can be used to test materials in various gaseous environments from atmospheric pressure to a vacuum. It allows the thermal transmission properties of insulating materials to be measured from just above ambient temperature down to temperatures below liquid hydrogen. However, NIST did not generate data below 77 K temperature for the reference material in question. This paper describes a test method used at NASA's Marshall Space Flight Center (MSFC) to optimize thermal conductivity measurements during the development of thermal protection systems. The test method extends the usability range of this reference material by generating data at temperatures lower than 77 K. Information provided by this test is discussed, as are the capabilities of the MSFC Hydrogen Test Facility, where advanced methods for materials testing are routinely developed and optimized in support of aerospace applications.

  16. Liquid temperature measuring method and device therefor

    Energy Technology Data Exchange (ETDEWEB)

    Maruyama, Fumi; Karasawa, Hirokazu

    1995-06-02

    In the present invention, temperature of liquid metal in coolants in an FBR type reactor can accurately be measured at rapid response time. Namely, ultrasonic waves are emitted from an ultrasonic wave sensor disposed in the air to a guide wave tube. Ultrasonic waves are reflected at reflection plates disposed at front and back or upper and lower portions of a small hole disposed to the wave guide tube. The reflected waves are received by the sensor described above. The difference of the reaching time of the reflected waves from the reflecting plates disposed at the front and the back or the upper and lower portions is measured. The speed of sounds in this case is determined based on the size of the small hole and the distance of the upper and the lower reflection plates. The speed of sounds is determined by the formula below: V(m/s) = 2500 - 0.52 T, where T: temperature. The temperature of the liquid can easily be calculated based on the formula. Accordingly, since the speed of the ultrasonic waves from their emission to the reception is msec order, and the processing of the signals are simple, the temperature can be measured at a response time of several msecs. In addition, since the ultrasonic wave sensor is disposed at the outside of the reactor, no special countermeasure for environmental circumstances is necessary, to improve maintenance ability. (I.S.).

  17. High temperature measurement of water vapor absorption

    Science.gov (United States)

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

    1985-01-01

    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.

  18. Electron temperature measurement in Z-pinch

    International Nuclear Information System (INIS)

    Gerusov, A.V.; Orlov, M.M.; Terent'ev, A.R.; Khrabrov, V.A.

    1987-01-01

    Measurement of temperature of emitting plasma sheath in noncylindrical Z-pinch in neon at the stage of convergence to the axis, based on comparing the intensity of spectral lines belonging to Ne1, Ne2, is performed. Line intensity relation dependence was determined using calculations according to emitting-collision model. Spectra were recorded by electron-optical converter and relative intensity was determined by subsequent photometry of photolayer. Cylindric symmetrical MHD-calculations during which temperature and the observed line intensity relation were determined, are conducted

  19. Irradiation temperature measurements in the surveillance program

    International Nuclear Information System (INIS)

    Pav, T.; Krhounek, V.

    1991-01-01

    Evaluation of the diamond monitor method for the determination of the irradiation temperature in the surveillance programme of WWER-440 reactors is discussed. One of the difficulties with the practical application of the method is that the measured values of irradiation temperature are unlikely high. Using a thermodynamical model of the processes in the annealing of the irradiated diamond crystals, it was shown that experimental difficulties came from the principles of the method used. An analysis was performed of the thermal field inside the capsule of the surveillance chain in operational conditions, using the finite element method. The diamond monitor method was suggested to be eliminated from the surveillance programme and the use was proposed of the value of 273+-3 degC (as the most likely value) for the irradiation temperature of surveillance samples in WWER-440 reactors. (Z.S.). 3 tabs., 6 figs., 4 refs

  20. Self-Healing Networks: Redundancy and Structure

    Science.gov (United States)

    Quattrociocchi, Walter; Caldarelli, Guido; Scala, Antonio

    2014-01-01

    We introduce the concept of self-healing in the field of complex networks modelling; in particular, self-healing capabilities are implemented through distributed communication protocols that exploit redundant links to recover the connectivity of the system. We then analyze the effect of the level of redundancy on the resilience to multiple failures; in particular, we measure the fraction of nodes still served for increasing levels of network damages. Finally, we study the effects of redundancy under different connectivity patterns—from planar grids, to small-world, up to scale-free networks—on healing performances. Small-world topologies show that introducing some long-range connections in planar grids greatly enhances the resilience to multiple failures with performances comparable to the case of the most resilient (and least realistic) scale-free structures. Obvious applications of self-healing are in the important field of infrastructural networks like gas, power, water, oil distribution systems. PMID:24533065

  1. Global rainbow refractometry for droplet temperature measurement

    International Nuclear Information System (INIS)

    Pascal Lemaitre; Emmanuel Porcheron; Amandine Nuboer; Philippe Brun; Pierre Cornet; Jeanne Malet; Jacques Vendel; Laurent Bouilloux; Gerard Grehan

    2005-01-01

    Full text of publication follows: In order to establish an accurate database to characterize the heat and mass transfers between a spray and the atmosphere with thermal-hydraulic conditions representative of a hypothetical nuclear reactor accident in the containment enclosure of a pressurized water reactor (PWR), the French Institut de Radioprotection et de Surete Nucleaire (IRSN) has developed the TOSQAN experimental facility. This experiment is highly instrumented with non-intrusive diagnostics allowing to measure droplet size and velocity and gas concentrations [1]. The aim of this work is to present the Global Rainbow Thermometry (GRT), which is an advanced non-intrusive optical diagnostic, developed to measure the mean temperature of a set of falling droplets, in a measurement volume of 1 cm 3 . The final paper will be divided in three parts. In the first one, we will explain the principle of the rainbow formation and how droplet temperature can be deduced from the rainbow analysis [2]. This part will be illustrated with the theoretical background on the rainbow and numerical simulations of the global rainbow. The second part will be devoted to present the global rainbow experimental set-up we have developed on optical table, its experimental qualification and finally its implementation on the TOSQAN facility [3]. Finally, we will present the temperature measurements achieved in TOSQAN for thermal-hydraulic conditions representative of a hypothetical nuclear reactor accident. These measurements are useful to characterize the heat and mass transfers between the spraying droplets and the air-steam mixture composing the atmosphere. This analysis will be exposed in a two companion papers. References: [1] E. Porcheron, P. Brun, P. Cornet, J. Malet, J. Vendel. Optical diagnostics applied for single and multi-phase flow characterization in the TOSQAN facility dedicated for thermal hydraulic containment studies. NURETH-10 Seoul, Korea, October 5-9, 2003. [2] P

  2. Global rainbow refractometry for droplet temperature measurement

    Energy Technology Data Exchange (ETDEWEB)

    Pascal Lemaitre; Emmanuel Porcheron; Amandine Nuboer; Philippe Brun; Pierre Cornet; Jeanne Malet; Jacques Vendel; Laurent Bouilloux [Institut de Radioprotection et de Surete Nucleaire DSU/SERAC, BP 68, 91192 Gif-sur-Yvette Cedex (France); Gerard Grehan [UMR 6614 CORIA, Laboratoire d' Electromagnetisme et Systemes Particulaires Site Universitaire du Madrillet, Avenue de l' universite BP 12, 76 801 Saint Etienne du Rouvray Cedex, (France)

    2005-07-01

    Full text of publication follows: In order to establish an accurate database to characterize the heat and mass transfers between a spray and the atmosphere with thermal-hydraulic conditions representative of a hypothetical nuclear reactor accident in the containment enclosure of a pressurized water reactor (PWR), the French Institut de Radioprotection et de Surete Nucleaire (IRSN) has developed the TOSQAN experimental facility. This experiment is highly instrumented with non-intrusive diagnostics allowing to measure droplet size and velocity and gas concentrations [1]. The aim of this work is to present the Global Rainbow Thermometry (GRT), which is an advanced non-intrusive optical diagnostic, developed to measure the mean temperature of a set of falling droplets, in a measurement volume of 1 cm{sup 3}. The final paper will be divided in three parts. In the first one, we will explain the principle of the rainbow formation and how droplet temperature can be deduced from the rainbow analysis [2]. This part will be illustrated with the theoretical background on the rainbow and numerical simulations of the global rainbow. The second part will be devoted to present the global rainbow experimental set-up we have developed on optical table, its experimental qualification and finally its implementation on the TOSQAN facility [3]. Finally, we will present the temperature measurements achieved in TOSQAN for thermal-hydraulic conditions representative of a hypothetical nuclear reactor accident. These measurements are useful to characterize the heat and mass transfers between the spraying droplets and the air-steam mixture composing the atmosphere. This analysis will be exposed in a two companion papers. References: [1] E. Porcheron, P. Brun, P. Cornet, J. Malet, J. Vendel. Optical diagnostics applied for single and multi-phase flow characterization in the TOSQAN facility dedicated for thermal hydraulic containment studies. NURETH-10 Seoul, Korea, October 5-9, 2003. [2] P

  3. Wireless sensor for temperature and humidity measurement

    Science.gov (United States)

    Drumea, Andrei; Svasta, Paul

    2010-11-01

    Temperature and humidity sensors have a broad range of applications, from heating and ventilation of houses to controlled drying of fruits, vegetables or meat in food industry. Modern sensors are integrated devices, usually MEMS, factory-calibrated and with digital output of measured parameters. They can have power down modes for reduced energy consumption. Such an integrated device allows the implementation of a battery powered wireless sensor when coupled with a low power microcontroller and a radio subsystem. A radio sensor can work independently or together with others in a radio network. Presented paper focuses mainly on measurement and construction aspects of sensors for temperature and humidity designed and implemented by authors; network aspects (communication between two or more sensors) are not analyzed.

  4. Structural redundance of NPPs and diagnostics

    International Nuclear Information System (INIS)

    Znyshev, V.V.; Sabaev, E.F.

    1988-01-01

    A new approach to functional diagnosis of NPP state based on structural redundance, owing to which in major of the facilities there are elements identical as to the structure and operational conditions, is suggested. The difference from zero by the given value for one parameter measured for various identical elements is an indicator of a failed element and a signal for diagnostic analysis

  5. Software engineering : redundancy is key

    NARCIS (Netherlands)

    Brand, van den M.G.J.; Groote, J.F.

    2015-01-01

    Software engineers are humans and so they make lots of mistakes. Typically 1 out of 10 to 100 tasks go wrong. The only way to avoid these mistakes is to introduce redundancy in the software engineering process. This article is a plea to consciously introduce several levels of redundancy for each

  6. Temperature measuring element in nuclear reactors

    International Nuclear Information System (INIS)

    Wada, Takashi.

    1987-01-01

    Purpose: To easily measure the partial maximum temperature at a portion within the nuclear reactor where the connection with the external portion is difficult. Constitution: Sodium, potassium or the alloy thereof with high heat expansion coefficient is packed into an elastic vessel having elastic walls contained in a capsule. A piercing member formed into an acute triangle is attached to one end in the direction of expansion and contraction of the elastic container. The two sides of the triangle form an acute knife edge. A diaphragm is disposed within a capsule at a position opposed to the sharpened direction of the piercing member. Such a capsule is placed in a predetermined position of the nuclear reactor. The elastic vessel causes thermal expansion displacement depending on the temperature at a certain position, by which the top end of the pierce member penetrates through the diaphragm. A pierced scar of a penetration length depending on the temperature is resulted to the diaphragm. The length of the piercing damage is electroscopically observed and compared with the calibration curve to recognize the maximum temperature in the predetermined portion of the nuclear reactor. (Kamimura, M.)

  7. Radiation Hardened Structured ASIC Platform with Compensation of Delay for Temperature and Voltage Variations for Multiple Redundant Temporal Voting Latch Technology

    Science.gov (United States)

    Ardalan, Sasan (Inventor)

    2018-01-01

    The invention relates to devices and methods of maintaining the current starved delay at a constant value across variations in voltage and temperature to increase the speed of operation of the sequential logic in the radiation hardened ASIC design.

  8. Density and temperature measurement using CARS spectroscopy

    International Nuclear Information System (INIS)

    Hirth, A.; Vollrath, K.

    1979-01-01

    Coherent Anti Stokes Raman Scattering (CARS) a technique derived from nonlinear optics offers two major advantages compared with the spontaneous Raman method: improved scattering efficiency and spatial coherence of the scattered signal. The theory of the coherent mixing in resonant media serves as a quantitative background of the CARS technique. A review of several applications on plasma physics and gasdynamics is given, which permits to consider the CARS spectroscopy as a potential method for nonintrusive measurement of local concentration and temperature in gas flows and reactive media. (Auth.)

  9. LOFT fuel rod surface temperature measurement testing

    International Nuclear Information System (INIS)

    Eaton, A.M.; Tolman, E.L.; Solbrig, C.W.

    1978-01-01

    Testing of the LOFT fuel rod cladding surface thermocouples has been performed to evaluate how accurately the LOFT thermocouples measure the cladding surface temperature during a loss-of-coolant accident (LOCA) sequence and what effect, if any, the thermocouple would have on core performance. Extensive testing has been done to characterize the thermocouple design. Thermal cycling and corrosion testing of the thermocouple weld design have provided an expected lifetime of 6000 hours when exposed to reactor coolant conditions of 620 K and 15.9 MPa and to sixteen thermal cycles with an initial temperature of 480 K and peak temperatures ranging from 870 to 1200K. Departure from nucleate boiling (DNB) tests have indicated a DNB penalty (5 to 28% lower) during steady state operation and negligible effects during LOCA blowdown caused by the LOFT fuel rod surface thermocouple arrangement. Experience with the thermocouple design in Power Burst Facility (PBF) and LOFT nonnuclear blowdown testing has been quite satisfactory. Tests discussed here were conducted using both stainless steel and zircaloy-clad electrically heated rod in the LOFT Test Support Facility (LTSF) blowdown simulation loop

  10. Measurement system for ultrahigh temperature thermophysical properties

    International Nuclear Information System (INIS)

    Fukuyama, Hiroyuki

    2015-01-01

    Properties and Simulations Probed with Electromagnetic Containerless Technique (PROSPECT) is a measurement system for ultrahigh temperature thermophysical properties to be able to measure thermophysical properties with high precision by combining AC magnetic field (electromagnetic levitation device) and DC magnetic field (superconducting magnet) to realize the static floating state of metallic melt, in other words, the state of suppressing the surface vibration of droplets, translational motion, and internal convection. The electromagnetic levitation method is a method to obtain a floating force due to the Lorentz force generated by the interaction between high-frequency current flowing in the coil and the induced current generated in a sample, and to heat/melt the sample with the Joule heat generated by its induced current. This paper roughly explains the element technologies of PROSPECT with a focus on the laser modulation calorimetry (laser periodic heating method), normal spectral emissivity measurement method, density measurement, and surface tension measurement method. Furthermore, as the application of PROSPECT to new research deployment, it introduces the observation of phase separation structure in the supercooled solidification structure of Cu-Co alloy. (A.O.)

  11. Apparatus for accurately measuring high temperatures

    Science.gov (United States)

    Smith, D.D.

    The present invention is a thermometer used for measuring furnace temperatures in the range of about 1800/sup 0/ to 2700/sup 0/C. The thermometer comprises a broadband multicolor thermal radiation sensor positioned to be in optical alignment with the end of a blackbody sight tube extending into the furnace. A valve-shutter arrangement is positioned between the radiation sensor and the sight tube and a chamber for containing a charge of high pressure gas is positioned between the valve-shutter arrangement and the radiation sensor. A momentary opening of the valve shutter arrangement allows a pulse of the high gas to purge the sight tube of air-borne thermal radiation contaminants which permits the radiation sensor to accurately measure the thermal radiation emanating from the end of the sight tube.

  12. Temperature measurements inside nuclear reactor cores

    International Nuclear Information System (INIS)

    Tarassenko, Serge

    1969-11-01

    Non negligible errors may happen in nuclear reactor temperature measurements using magnesium oxide insulated and stainless steel sheathed micro-wire thermocouples, when these thermometric lines are placed under operational conditions typical of electrical power stations. The present work shows that this error is principally due to electrical hysteresis and polarization phenomena in the insulator subjected to the strong fields generated by common-mode voltages. These phenomena favour the unsymmetrical common-mode current flow and thus lead to the differential-mode voltage generation which is superposing on the thermoelectric hot junction potential. A calculation and an experimental approach make possible the importance of the magnesium oxide insulating characteristics, the hot junction insulation, the choice of the main circuits in the data processing equipment as well as the galvanic isolation performances and the common-mode rejection features of all the measurement circuits. A justification is thereby given for the severe conditions imposed for the acceptance of thermoelectric materials; some particular precautions to be taken are described, as well as the high performance characteristics which have to be taken into account in choosing measurement systems linked to thermometric circuits with sheathed micro-wire thermocouples. (author) [fr

  13. Quantum redundancies and local realism

    International Nuclear Information System (INIS)

    Horodecki, R.; Horodecki, P.

    1994-01-01

    The basic properties of quantum redundancies are presented. The previous definitions of the informationally coherent quantum (ICQ) system are generalized in terms of the redundancies. The ICQ systems are also considered in the context of local realism in terms of the information integrity factor η. The classical region η≤qslant[1]/[2] for the two classes of mixed, nonfactorizable states admitting the local hidden variable model is found. ((orig.))

  14. Temporal information partitioning: Characterizing synergy, uniqueness, and redundancy in interacting environmental variables

    Science.gov (United States)

    Goodwell, Allison E.; Kumar, Praveen

    2017-07-01

    Information theoretic measures can be used to identify nonlinear interactions between source and target variables through reductions in uncertainty. In information partitioning, multivariate mutual information is decomposed into synergistic, unique, and redundant components. Synergy is information shared only when sources influence a target together, uniqueness is information only provided by one source, and redundancy is overlapping shared information from multiple sources. While this partitioning has been applied to provide insights into complex dependencies, several proposed partitioning methods overestimate redundant information and omit a component of unique information because they do not account for source dependencies. Additionally, information partitioning has only been applied to time-series data in a limited context, using basic pdf estimation techniques or a Gaussian assumption. We develop a Rescaled Redundancy measure (Rs) to solve the source dependency issue, and present Gaussian, autoregressive, and chaotic test cases to demonstrate its advantages over existing techniques in the presence of noise, various source correlations, and different types of interactions. This study constitutes the first rigorous application of information partitioning to environmental time-series data, and addresses how noise, pdf estimation technique, or source dependencies can influence detected measures. We illustrate how our techniques can unravel the complex nature of forcing and feedback within an ecohydrologic system with an application to 1 min environmental signals of air temperature, relative humidity, and windspeed. The methods presented here are applicable to the study of a broad range of complex systems composed of interacting variables.

  15. High temperature hall effect measurement system design, measurement and analysis

    Science.gov (United States)

    Berkun, Isil

    A reliable knowledge of the transport properties of semiconductor materials is essential for the development and understanding of a number of electronic devices. In this thesis, the work on developing a Hall Effect measurement system with software based data acqui- sition and control for a temperature range of 300K-700K will be described. A system was developed for high temperature measurements of materials including single crystal diamond, poly-crystalline diamond, and thermoelectric compounds. An added capability for monitor- ing the current versus voltage behavior of the contacts was used for studying the influence of ohmic and non-ohmic contacts on Hall Effect measurements. The system has been primar- ily used for testing the transport properties of boron-doped single crystal diamond (SCD) deposited in a microwave plasma-assisted chemical vapor deposition (MPCVD) reactor [1]. Diamond has several outstanding properties that are of high interest for its development as an electronic material. These include a relatively wide band gap of 5.5 (eV), high thermal conductivity, high mobility, high saturation velocity, and a high breakdown voltage. For a temperature range of 300K-700K, IV curves, Hall mobilities and carrier concentrations are shown. Temperature dependent Hall effect measurements have shown carrier concentrations from below 1017cm --3 to approximately 1021 cm--3 with mobilities ranging from 763( cm2/V s) to 0.15(cm 2/V s) respectively. Simulation results have shown the effects of single and mixed carrier models, activation energies, effective mass and doping concentrations. These studies have been helpful in the development of single crystal diamond for diode applications. Reference materials of Ge and GaAs were used to test the Hall Effect system. The system was also used to characterize polycrystalline diamond deposited on glass for electrochemical applications, and Mg2(Si,Sn) compounds which are promising candidates of low-cost, light weight and non

  16. Crowdsourcing urban air temperature measurements using smartphones

    Science.gov (United States)

    Balcerak, Ernie

    2013-10-01

    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.

  17. Bulk temperature measurement in thermally striped pipe flows

    International Nuclear Information System (INIS)

    Lemure, N.; Olvera, J.R.; Ruggles, A.E.

    1995-12-01

    The hot leg flows in some Pressurized Water Reactor (PWR) designs have a temperature distribution across the pipe cross-section. This condition is often referred to as a thermally striped flow. Here, the bulk temperature measurement of pipe flows with thermal striping is explored. An experiment is conducted to examine the feasibility of using temperature measurements on the external surface of the pipe to estimate the bulk temperature of the flow. Simple mixing models are used to characterize the development of the temperature profile in the flow. Simple averaging techniques and Backward Propagating Neural Net are used to predict bulk temperature from the external temperature measurements. Accurate bulk temperatures can be predicted. However, some temperature distributions in the flow effectively mask the bulk temperature from the wall and cause significant error in the bulk temperature predicted using this technique

  18. Redundant Sb condensation on GaSb epilayers grown by molecular beam epitaxy during cooling procedure

    International Nuclear Information System (INIS)

    Arpapay, B.; Şahin, S.; Arıkan, B.; Serincan, U.

    2014-01-01

    The effect of four different cooling receipts on the surface morphologies of unintentionally-doped GaSb epilayers on GaSb (100) substrates grown by molecular beam epitaxy is reported. Those receipts include three different Sb beam equivalent pressure (BEP) levels and two different termination temperatures. Surface morphologies of epilayers were examined by wet etching, surface profiler, atomic force microscopy, scanning electron microscopy and Raman spectroscopy. The results demonstrate that during the cooling period, a Sb BEP of 4.00 × 10 −4 Pa at a termination temperature of 400 °C induces a smooth surface without Sb condensation whereas same Sb BEP at a termination temperature of 350 °C forms a 300 nm thick Sb layer on the surface. In addition, it is revealed that by applying a wet etching procedure and using a surface profiler it is possible to identify this condensed layer from the two-sloped feature of mesa profile. - Highlights: • Sb beam flux termination temperature is crucial for redundant Sb condensation. • Sb beam flux level has a role on the thickness of redundant condensed Sb layer. • Redundant Sb layer thickness can be measured by two-sloped mesa structure

  19. Measuring brightness temperature distributions of plasma bunches

    International Nuclear Information System (INIS)

    Kirko, V.I.; Stadnichenko, I.A.

    1981-01-01

    The possibility of restoration of brightness temperature distribution along plasma jet on the base of a simple ultra high- speed photography and subsequent photometric treatment is shown. The developed technique has been applied for finding spectral radiation intensity and brightness temperature of plasma jets of a tubular gas-cumulative charge and explosive plasma compressor. The problem of shock wave front has been successfully solved and thus distribution of above parameters beginning from the region preceeding the shock wave has been obtained [ru

  20. Distributed redundancy and robustness in complex systems

    KAUST Repository

    Randles, Martin

    2011-03-01

    The uptake and increasing prevalence of Web 2.0 applications, promoting new large-scale and complex systems such as Cloud computing and the emerging Internet of Services/Things, requires tools and techniques to analyse and model methods to ensure the robustness of these new systems. This paper reports on assessing and improving complex system resilience using distributed redundancy, termed degeneracy in biological systems, to endow large-scale complicated computer systems with the same robustness that emerges in complex biological and natural systems. However, in order to promote an evolutionary approach, through emergent self-organisation, it is necessary to specify the systems in an \\'open-ended\\' manner where not all states of the system are prescribed at design-time. In particular an observer system is used to select robust topologies, within system components, based on a measurement of the first non-zero Eigen value in the Laplacian spectrum of the components\\' network graphs; also known as the algebraic connectivity. It is shown, through experimentation on a simulation, that increasing the average algebraic connectivity across the components, in a network, leads to an increase in the variety of individual components termed distributed redundancy; the capacity for structurally distinct components to perform an identical function in a particular context. The results are applied to a specific application where active clustering of like services is used to aid load balancing in a highly distributed network. Using the described procedure is shown to improve performance and distribute redundancy. © 2010 Elsevier Inc.

  1. Operational methods of thermodynamics. Volume 1 - Temperature measurement

    Science.gov (United States)

    Eder, F. X.

    The principles of thermometry are examined, taking into account the concept of temperature, the Kelvin scale, the statistical theory of heat, negative absolute temperatures, the thermodynamic temperature scale, the thermodynamic temperature scale below 1 K, noise thermometry, temperature scales based on black-body radiation, acoustical thermometry, and the International Practical Temperature Scale 1968. Aspects of practical temperature measurement are discussed, giving attention to thermometers based on the expansion of a gas or a liquid, instruments utilizing the relative thermal expansion of two different metals, devices measuring the vapor pressure of a liquid, thermocouples, resistance thermometers, radiation pyrometers of various types, instruments utilizing the temperature dependence of a number of material characteristics, devices for temperature control, thermometer calibration, and aspects of thermometer installation and inertia. A description is presented of the approaches employed for the measurement of low temperatures.

  2. 40 CFR 91.309 - Engine intake air temperature measurement.

    Science.gov (United States)

    2010-07-01

    ... measurement. 91.309 Section 91.309 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Provisions § 91.309 Engine intake air temperature measurement. (a) Engine intake air temperature measurement must be made within 100 cm of the air-intake of the engine. The measurement location must be either in...

  3. 7 CFR 28.301 - Measurement: humidity; temperature.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Measurement: humidity; temperature. 28.301 Section 28... for Length of Staple § 28.301 Measurement: humidity; temperature. The length of staple of any cotton... its fibers under a relative humidity of the atmosphere of 65 percent and a temperature of 70° F. ...

  4. Novel method for noncontact measurement of particle temperatures

    NARCIS (Netherlands)

    Wagenaar, B.M.; Meijer, R.; Kuipers, J.A.M.; van Swaaij, W.P.M.

    1995-01-01

    A nonintrusive temperature measurement technique is developed for noncontact measurement of the temperature of single particles with <200 µm dia. It is based on the temperature dependence of the fluorescence spectrum resulting from irradiation of a certain phosphor mixture with UV light by applying

  5. Novel method for noncontact measurement of particle temperatures

    NARCIS (Netherlands)

    Wagenaar, B.M.; Wagenaar, B.M.; Meijer, R.; Kuipers, J.A.M.; van Swaaij, Willibrordus Petrus Maria

    1995-01-01

    A nonintrusive temperature measurement technique is developed for noncontact measurement of the temperature of single particles with < 200 m dia. It is based on the temperature dependence of the fluorescence spectrum resulting from irradiation of a certain phosphor mixture with UV light by applying

  6. Measurement of the argon plasma temperature by use of pyrometer

    International Nuclear Information System (INIS)

    Wang Fanhou; Jing Fuqian

    2002-01-01

    The author describes in detail how to use pyrometer to measure the plasma temperature. The temperatures of shock-generated argon plasmas are given in the present work. Measured results of temperature-pressure curve are compared with calculated results using Saha-Debye-Huckel model, which are in good agreement

  7. Measuring Method for Lightning Channel Temperature

    Science.gov (United States)

    Li, X.; Zhang, J.; Chen, L.; Xue, Q.; Zhu, R.

    2016-09-01

    In this paper, we demonstrate the temperature of lightning channel utilizing the theory of lightning spectra and the model of local thermodynamic equilibrium (LTE). The impulse current generator platform (ICGS) was used to simulate the lightning discharge channel, and the spectral energy of infrared spectroscopy (930 nm) and the visible spectroscopy (648.2 nm) of the simulated lightning has been calculated. Results indicate that the peaks of luminous intensity of both infrared and visible spectra increase with the lightning current intensity in range of 5-50 kA. Based on the results, the temperature of the lightning channel is derived to be 6140.8-10424 K. Moreover, the temperature of the channel is approximately exponential to the lightning current intensity, which shows good agreement with that of the natural lightning cases.

  8. Neural redundancy applied to the parity space for signal validation

    International Nuclear Information System (INIS)

    Mol, Antonio Carlos de Abreu; Pereira, Claudio Marcio Nascimento Abreu; Martinez, Aquilino Senra

    2005-01-01

    The objective of signal validation is to provide more reliable information from the plant sensor data The method presented in this work introduces the concept of neural redundancy and applies it to the space parity method [1] to overcome an inherent deficiency of this method - the determination of the best estimative of the redundant measures when they are inconsistent. The concept of neural redundancy consists on the calculation of a redundancy through neural networks based on the time series of the own state variable. Therefore, neural networks, dynamically trained with the time series, will estimate the current value of the own measure, which will be used as referee of the redundant measures in the parity space. For this purpose the neural network should have the capacity to supply the neural redundancy in real time and with maximum error corresponding to the group deviation. The historical series should be enough to allow the estimate of the next value, during transients and at the same time, it should be optimized to facilitate the retraining of the neural network to each acquisition. In order to have the capacity to reproduce the tendency of the time series even under accident condition, the dynamic training of the neural network privileges the recent points of the time series. The tests accomplished with simulated data of a nuclear plant, demonstrated that this method applied on the parity space method improves the signal validation process. (author)

  9. Neural redundancy applied to the parity space for signal validation

    Energy Technology Data Exchange (ETDEWEB)

    Mol, Antonio Carlos de Abreu; Pereira, Claudio Marcio Nascimento Abreu [Instituto de Engenharia Nuclear (IEN), Rio de Janeiro, RJ (Brazil)]. E-mail: cmnap@ien.gov.br; Martinez, Aquilino Senra [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia]. E-mail: aquilino@lmp.br

    2005-07-01

    The objective of signal validation is to provide more reliable information from the plant sensor data The method presented in this work introduces the concept of neural redundancy and applies it to the space parity method [1] to overcome an inherent deficiency of this method - the determination of the best estimative of the redundant measures when they are inconsistent. The concept of neural redundancy consists on the calculation of a redundancy through neural networks based on the time series of the own state variable. Therefore, neural networks, dynamically trained with the time series, will estimate the current value of the own measure, which will be used as referee of the redundant measures in the parity space. For this purpose the neural network should have the capacity to supply the neural redundancy in real time and with maximum error corresponding to the group deviation. The historical series should be enough to allow the estimate of the next value, during transients and at the same time, it should be optimized to facilitate the retraining of the neural network to each acquisition. In order to have the capacity to reproduce the tendency of the time series even under accident condition, the dynamic training of the neural network privileges the recent points of the time series. The tests accomplished with simulated data of a nuclear plant, demonstrated that this method applied on the parity space method improves the signal validation process. (author)

  10. Measuring the temperature of hot nuclear fragments

    International Nuclear Information System (INIS)

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

    2010-01-01

    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.

  11. The measurement of temperature effect of light output of scintillators

    International Nuclear Information System (INIS)

    Ji Changsong; Zhou Zaiping; Zhang Longfang

    1999-01-01

    The author describes a experiment equipment used for measurement of temperature effect of light output of scintillators; gives some measurement results of temperature effect of light output for NaI(Tl), CsI(Tl), plastic scintillator, ZnS(Ag), anthracene crystal glass scintillator; analyzes the error factors affecting the measurement results. The total uncertainty of the temperature effect measurement for NaI(Tl) and plastic scintillator is 11%

  12. Temperature transient response measurement in flowing water

    International Nuclear Information System (INIS)

    Rainbird, J.C.

    1980-01-01

    A specially developed procedure is described for determining the thermal transient response of thermocouples and other temperature transducers when totally immersed in flowing water. The high velocity heat transfer conditions associated with this facility enable thermocouple response times to be predicted in other fluids. These predictions can be confirmed by electrical analogue experiments. (author)

  13. Electron Density and Temperature Measurements, and Abundance ...

    Indian Academy of Sciences (India)

    tribpo

    tics—emission lines. Dwivedi, Curdt & Wilhelm (1997, 1999a) carried out an observing sequence based on a theoretical study by Dwivedi & Mohan (1995), with intercombination/forbidden. Ne VI and Mg VI lines, which are formed at essentially the same temperature. (4 × 105 K), according to Arnaud & Rothenflug (1985).

  14. Isothermal temperature reactivity coefficient measurement in TRIGA reactor

    International Nuclear Information System (INIS)

    Zagar, T.; Ravnik, M.; Trkov, A.

    2002-01-01

    Direct measurement of an isothermal temperature reactivity coefficient at room temperatures in TRIGA Mark II research reactor at Jozef Stefan Institute in Ljubljana is presented. Temperature reactivity coefficient was measured in the temperature range between 15 o C and 25 o C. All reactivity measurements were performed at almost zero reactor power to reduce or completely eliminate nuclear heating. Slow and steady temperature decrease was controlled using the reactor tank cooling system. In this way the temperatures of fuel, of moderator and of coolant were kept in equilibrium throughout the measurements. It was found out that TRIGA reactor core loaded with standard fuel elements with stainless steel cladding has small positive isothermal temperature reactivity coefficient in this temperature range.(author)

  15. A Measurement of the Cosmic Microwave Background Temperature ...

    Indian Academy of Sciences (India)

    tribpo

    power law form spectrum. Besides the inevitable ... measurement of the thermodynamic temperature of the CMB at 1280 MHz. 2. The receiver ... from the feed assembly and the third term is the receiver temperature as referred to the circulator ...

  16. An intelligent instrument for measuring exhaust temperature of marine engine

    Science.gov (United States)

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

    2006-12-01

    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.

  17. Nanosecond-resolved temperature measurements using magnetic nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Wenbiao; Zhang, Pu [School of Automation, Huazhong University of Science and Technology, Wuhan 430074 (China); Liu, Wenzhong, E-mail: lwz7410@hust.edu.cn [School of Automation, Huazhong University of Science and Technology, Wuhan 430074 (China); Key Laboratory of Image Processing and Intelligent Control, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2016-05-15

    Instantaneous and noninvasive temperature measurements are important when laser thermotherapy or welding is performed. A noninvasive nanosecond-resolved magnetic nanoparticle (MNP) temperature measurement system is described in which a transient change in temperature causes an instantaneous change in the magnetic susceptibilities of the MNPs. These transient changes in the magnetic susceptibilities are rapidly recorded using a wideband magnetic measurement system with an upper frequency limit of 0.5 GHz. The Langevin function (the thermodynamic model characterizing the MNP magnetization process) is used to obtain the temperature information. Experiments showed that the MNP DC magnetization temperature-measurement system can detect a 14.4 ns laser pulse at least. This method of measuring temperature is likely to be useful for acquiring the internal temperatures of materials irradiated with lasers, as well as in other areas of research.

  18. The heuristic value of redundancy models of aging.

    Science.gov (United States)

    Boonekamp, Jelle J; Briga, Michael; Verhulst, Simon

    2015-11-01

    Molecular studies of aging aim to unravel the cause(s) of aging bottom-up, but linking these mechanisms to organismal level processes remains a challenge. We propose that complementary top-down data-directed modelling of organismal level empirical findings may contribute to developing these links. To this end, we explore the heuristic value of redundancy models of aging to develop a deeper insight into the mechanisms causing variation in senescence and lifespan. We start by showing (i) how different redundancy model parameters affect projected aging and mortality, and (ii) how variation in redundancy model parameters relates to variation in parameters of the Gompertz equation. Lifestyle changes or medical interventions during life can modify mortality rate, and we investigate (iii) how interventions that change specific redundancy parameters within the model affect subsequent mortality and actuarial senescence. Lastly, as an example of data-directed modelling and the insights that can be gained from this, (iv) we fit a redundancy model to mortality patterns observed by Mair et al. (2003; Science 301: 1731-1733) in Drosophila that were subjected to dietary restriction and temperature manipulations. Mair et al. found that dietary restriction instantaneously reduced mortality rate without affecting aging, while temperature manipulations had more transient effects on mortality rate and did affect aging. We show that after adjusting model parameters the redundancy model describes both effects well, and a comparison of the parameter values yields a deeper insight in the mechanisms causing these contrasting effects. We see replacement of the redundancy model parameters by more detailed sub-models of these parameters as a next step in linking demographic patterns to underlying molecular mechanisms. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Noise temperature measurements for the determination of the thermodynamic temperature of the melting point of palladium

    Energy Technology Data Exchange (ETDEWEB)

    Edler, F.; Kuhne, M.; Tegeler, E. [Bundesanstalt Physikalisch-Technische, Berlin (Germany)

    2004-02-01

    The thermodynamic temperature of the melting point of palladium in air was measured by noise thermometric methods. The temperature measurement was based on noise comparison using a two-channel arrangement to eliminate parasitic noises of electronic components by cross correlation. Three miniature fixed points filled with pure palladium (purity: {approx}99.99%, mass: {approx}90 g) were used to realize the melts of the fixed point metal. The measured melting temperature of palladium in air amounted to 1552.95 deg C {+-} 0.21 K (k = 2). This temperature is 0.45 K lower than the temperature of the melting point of palladium measured by radiation thermometry. (authors)

  20. Design and Implementation of High Precision Temperature Measurement Unit

    Science.gov (United States)

    Zeng, Xianzhen; Yu, Weiyu; Zhang, Zhijian; Liu, Hancheng

    2018-03-01

    Large-scale neutrino detector requires calibration of photomultiplier tubes (PMT) and electronic system in the detector, performed by plotting the calibration source with a group of designated coordinates in the acrylic sphere. Where the calibration source positioning is based on the principle of ultrasonic ranging, the transmission speed of ultrasonic in liquid scintillator of acrylic sphere is related to temperature. This paper presents a temperature measurement unit based on STM32L031 and single-line bus digital temperature sensor TSic506. The measurement data of the temperature measurement unit can help the ultrasonic ranging to be more accurate. The test results show that the temperature measurement error is within ±0.1°C, which satisfies the requirement of calibration source positioning. Take energy-saving measures, with 3.7V/50mAH lithium battery-powered, the temperature measurement unit can work continuously more than 24 hours.

  1. Measurement of temperature, electric conductivity and density of plasma

    International Nuclear Information System (INIS)

    Vasilevova, I.; Nefedov, A.; Oberman, F.; Urinson, A.

    1982-01-01

    Three instruments are briefly described developed by the High Temperatures Institute of the USSR Academy of Sciences for the measurement of plasma temperature, electric conductivity and density. The temperature measuring instrument uses as a standard a light source whose temperature may significantly differ from plasma temperature because three light fluxes are compared, namely the flux emitted by the plasma, the flux emitted directly by the standard source, and the flux emitted by the standard source after passage through the plasma. The results of measurement are computer processed. Electric conductivity is measured using a coil placed in a probe which is automatically extended for a time of maximally 0.3 seconds into the plasma stream. The equipment for measuring plasma density consists of a special single-channel monochromator, a temperature gauge, a plasma pressure gauge, and of a computer for processing the results of measurement. (Ha)

  2. 40 CFR 90.309 - Engine intake air temperature measurement.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Engine intake air temperature measurement. 90.309 Section 90.309 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Emission Test Equipment Provisions § 90.309 Engine intake air temperature measurement. (a) The measurement...

  3. Pirani pressure sensor with distributed temperature measurement

    NARCIS (Netherlands)

    de Jong, B.R.; Bula, W.P.; Zalewski, D.R.; van Baar, J.J.J.; Wiegerink, Remco J.

    2003-01-01

    Surface micro-machined distributed Pirani pressure gauges, with designed heater-to-heat sink distances (gap-heights) of 0.35 μm and 1.10 μm, are successfully fabricated, modeled and characterized. Measurements and model response correspond within 5% of the measured value in a pressure range of 10 to

  4. Air Temperature Measurements Using Dantec Draught Probes

    DEFF Research Database (Denmark)

    Kristensen, Martin Heine; Jensen, Jakob Søland; Jensen, Rasmus Lund

    This technical report is written based on investigations of Dantec measurement equipment used in a master thesis project by the authors in the period September 2014 to June 2015 (Kristensen & Jensen, 2015).......This technical report is written based on investigations of Dantec measurement equipment used in a master thesis project by the authors in the period September 2014 to June 2015 (Kristensen & Jensen, 2015)....

  5. Redundancy in Nigerian Business Organizations: Alternatives (Pp ...

    African Journals Online (AJOL)

    FIRST LADY

    Redundancy in Nigerian Business Organizations: Alternatives (Pp. ... When business downturns ... The galloping pace of information technologies is a harbinger of profound ... Redundant staff in public departments can also be retained as.

  6. Fluid temperature measurement technique by using Raman scattering

    International Nuclear Information System (INIS)

    An, Jeong Soo; Yang, Sun Kyu; Min, Kyung Ho; Chung, Moon Ki; Choi, Young Don

    1999-06-01

    Temperature measurement technique by using Raman scattering was developed for the liquid water at temperature of 20 - 90 degree C and atmospheric pressure. Strong relationship between Raman scattering characteristics and liquid temperature change was observed. Various kinds of measurement techniques, such as Peak Intensity, Peak Wavelength, FWHM (Full Width at Half Maximum), PMCR ( Polymer Monomer Concentration RAte), TSIR (Temperature Sensitive Intensity Ratio), IDIA (Integral Difference Intensity Area) were tested. TSIR has the highest accuracy in mean error or 0.1 deg C and standard deviation of 0.1248 deg C. This report is one of the results in developing process of Raman temperature measurement technique. Next research step is to develop Raman temperature measurement technique at the high temperature and high pressure conditions in single or two phase flows. (author). 13 refs., 3 tabs., 38 figs

  7. High Precision Infrared Temperature Measurement System Based on Distance Compensation

    Directory of Open Access Journals (Sweden)

    Chen Jing

    2017-01-01

    Full Text Available To meet the need of real-time remote monitoring of human body surface temperature for optical rehabilitation therapy, a non-contact high-precision real-time temperature measurement method based on distance compensation was proposed, and the system design was carried out. The microcontroller controls the infrared temperature measurement module and the laser range module to collect temperature and distance data. The compensation formula of temperature with distance wass fitted according to the least square method. Testing had been performed on different individuals to verify the accuracy of the system. The results indicate that the designed non-contact infrared temperature measurement system has a residual error of less than 0.2°C and the response time isless than 0.1s in the range of 0 to 60cm. This provides a reference for developing long-distance temperature measurement equipment in optical rehabilitation therapy.

  8. Measurement and analysis of reactivity temperature coefficient of CEFR

    International Nuclear Information System (INIS)

    Chen Yiyu; Hu Yun; Yang Xiaoyan; Fan Zhendong; Zhang Qiang; Zhao Jinkun; Li Zehua

    2013-01-01

    The reactivity temperature coefficient of CEFR was calculated by CITATION program and compared with the results calculated by correlative programs and measured from experiments for temperature effects. It is indicated that the calculation results from CITATION agree well with measured values. The reactivity temperature coefficient of CEFR is about -4 pcm/℃. The deviation of the measured values between the temperature increasing and decreasing processes is about 11%, which satisfies the experiment acceptance criteria. The measured results can validate the calculation ones by program and can provide important reference data for the safety operation of CEFR and the analysis of the reactivity balance in the reactor refueling situation. (authors)

  9. Reconstruction of core inlet temperature distribution by cold leg temperature measurements

    International Nuclear Information System (INIS)

    Saarinen, S.; Antila, M.

    2010-01-01

    The reduced core of Loviisa NPP contains 33 thermocouple measurements measuring the core inlet temperature. Currently, these thermocouple measurements are not used in determining the inlet temperature distribution. The average of cold leg temperature measurements is used as inlet temperature for each fuel assembly. In practice, the inlet temperature distribution is not constant. Thus, using a constant inlet temperature distribution induces asymmetries in the measured core power distribution. Using a more realistic inlet temperature distribution would help us to reduce virtual asymmetries of the core power distribution and increase the thermal margins of the core. The thermocouples at the inlet cannot be used directly to measure the inlet temperature accurately because the calibration of the thermocouples that is done at hot zero power conditions is no longer valid at full power, when there is temperature change across the core region. This is due to the effect of neutron irradiation on the Seebeck coefficient of the thermocouple wires. Therefore, we investigate in this paper a method to determine the inlet temperature distribution based on the cold leg temperature measurements. With this method we rely on the assumption that although the core inlet thermocouple measurements do not measure the absolute temperature accurately they do measure temperature changes with sufficient accuracy particularly in big disturbances. During the yearly testing of steam generator safety valves we observe a large temperature increase up to 12 degrees in the cold leg temperature. The change in the temperature of one of the cold legs causes a local disturbance in the core inlet temperature distribution. Using the temperature changes observed in the inlet thermocouple measurements we are able to fit six core inlet temperature response functions, one for each cold leg. The value of a function at an assembly inlet is determined only by the corresponding cold leg temperature disturbance

  10. Sharing the cost of redundant items

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Moulin, Hervé

    2014-01-01

    We ask how to share the cost of finitely many public goods (items) among users with different needs: some smaller subsets of items are enough to serve the needs of each user, yet the cost of all items must be covered, even if this entails inefficiently paying for redundant items. Typical examples...... are network connectivity problems when an existing (possibly inefficient) network must be maintained. We axiomatize a family cost ratios based on simple liability indices, one for each agent and for each item, measuring the relative worth of this item across agents, and generating cost allocation rules...... additive in costs....

  11. Multi-spectral pyrometer for gas turbine blade temperature measurement

    Science.gov (United States)

    Gao, Shan; Wang, Lixin; Feng, Chi

    2014-09-01

    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.

  12. Device for the alternative option of temperature measurement

    Science.gov (United States)

    Jargus, Jan; Nedoma, Jan; Fajkus, Marcel; Novak, Martin; Cubik, Jakub; Cvejn, Daniel; Vasinek, Vladimir

    2017-10-01

    Polydimethylsiloxane (PDMS) has good optical properties, and its composition offers the possibility of use in many applications (industry, security device, medicine applications and etc.). We focused on the alternative option of temperature measurement in this article. Our approach is based on measuring changes of chromaticity correlated temperature corresponding to changes in temperature. Described device uses an optical fiber with a defined layer of PDMS and luminophore and we assume that it can find use also in the field of security. The article describes the process of making the prototype of the device and its verification based on laboratory results. The measured temperature depends mainly on the type of optical fiber and the measured temperature range is determined by the thermal resistance of used optical fiber. Using a calibration measurement can determine the value of temperature with an accuracy of +/- 2,5 %.

  13. Temperature Measurement of Ceramic Materials Using a Multiwavelength Pyrometer

    Science.gov (United States)

    Ng, Daniel; Fralick, Gustave

    1999-01-01

    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.

  14. Measurement of temperature fluctuations and anomalous transport ...

    Indian Academy of Sciences (India)

    an isolated DC power supply (having negligible capacitance with respect to ground or the vacuum vessel) and the ion saturation current Б× drawn by the pair is obtained by measur- ing the voltage drop across a 10 Ω resistance using a battery operated isolation amplifier. The potential of the positively biased probe · is also ...

  15. Research on temperature measurement by X-ray transmission intensity

    International Nuclear Information System (INIS)

    Chen, Shuyue; Cheng, Rong

    2013-01-01

    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

  16. Influence of Sensor Ingestion Timing on Consistency of Temperature Measures

    National Research Council Canada - National Science Library

    Goodman, Daniel A; Kenefick, Robert W; Cadarette, Bruce S; Cheuvront, Samuel N

    2009-01-01

    ... (ITS) to measure core body temperature have been demonstrated. However, the effect of elapsed time between ITS ingestion and Tint measurement has not been thoroughly studied. Methods: Eight volunteers...

  17. Non-invasive body temperature measurement of wild chimpanzees using fecal temperature decline.

    Science.gov (United States)

    Jensen, Siv Aina; Mundry, Roger; Nunn, Charles L; Boesch, Christophe; Leendertz, Fabian H

    2009-04-01

    New methods are required to increase our understanding of pathologic processes in wild mammals. We developed a noninvasive field method to estimate the body temperature of wild living chimpanzees habituated to humans, based on statistically fitting temperature decline of feces after defecation. The method was established with the use of control measures of human rectal temperature and subsequent changes in fecal temperature over time. The method was then applied to temperature data collected from wild chimpanzee feces. In humans, we found good correspondence between the temperature estimated by the method and the actual rectal temperature that was measured (maximum deviation 0.22 C). The method was successfully applied and the average estimated temperature of the chimpanzees was 37.2 C. This simple-to-use field method reliably estimates the body temperature of wild chimpanzees and probably also other large mammals.

  18. Impulse method for temperature measurement of silicon detectors

    International Nuclear Information System (INIS)

    Kushpil, V.V.; Kushpil, S.A.; Petracek, V.

    1999-01-01

    A new impulse method of temperature measurement based on switching characteristic of the P-N junction is described. Temperature of silicon detector can be determined, due to the strong temperature dependence of minority carrier lifetime, from the charge registered during the switching-off process. The method has been tested in temperature range 25 - 60 deg C. Advantages, drawbacks and precision of this method are discussed

  19. Upgrade of the cooling water temperature measures system for HLS

    International Nuclear Information System (INIS)

    Guo Weiqun; Liu Gongfa; Bao Xun; Jiang Siyuan; Li Weimin; He Duohui

    2007-01-01

    The cooling water temperature measures system for HLS (Hefei Light Source) adopts EPICS to the developing platform and takes the intelligence temperature cruise instrument for the front control instrument. Data of temperatures are required by IOCs through Serial Port Communication, archived and searched by Channel Archiver. The system can monitor the real-time temperatures of many channels cooling water and has the function of history data storage, and data network search. (authors)

  20. Development of electron temperature measuring system by silicon drift detector

    International Nuclear Information System (INIS)

    Song Xianying; Yang Jinwei; Liao Min

    2007-12-01

    Soft X-ray spectroscopy with two channels Silicon Drift Detector (SDD) are adopted for electron temperature measuring on HL-2A tokamak in 2005. The working principle, design and first operation of the SDD soft X-ray spectroscopy are introduced. The measuring results of electron temperature are also presented. The results show that the SDD is very good detector for electron temperature measuring on HL-2A tokamak. These will become a solid basic work to establish SDD array for electron temperature profiling. (authors)

  1. The measurement of single particle temperature in plasma sprays

    International Nuclear Information System (INIS)

    Fincke, J.R.; Swank, W.D.; Bolsaitis, P.P.; Elliott, J.F.

    1990-01-01

    A measurement technique for simultaneously obtaining the size, velocity, temperature, and relative number density of particles entrained in high temperature flow fields is described. In determining the particle temperature from a two-color pyrometery technique, assumptions about the relative spectral emissivity of the particle are required. For situations in which the particle surface undergoes chemical reactions the assumption of grey body behavior is shown to introduce large Temperature measurement uncertainties. Results from isolated, laser heated, single particle measurements and in-flight data from the plasma spraying of WC-Co are presented. 10 refs., 5 figs

  2. Simulator of a fail detector system for redundant sensors

    International Nuclear Information System (INIS)

    Assumpcao Filho, E.O.; Nakata, H.

    1990-01-01

    A failure detection and isolation system (FDI) simulation program has been developed for IBM-PC microcomputers. The program, based on the sequencial likelihood ratio testing method developed by A. Wald, was implemented with Monte-Carlo technique. The calculated failure detection rate was favorably compared against the wind-tunnel experimental redundant temperature sensors. (author)

  3. Measurement of relative permittivity of LTCC ceramic at different temperatures

    Directory of Open Access Journals (Sweden)

    Qiulin Tan

    2014-02-01

    Full Text Available Devices based on LTCC (low-temperature co-fired ceramic technology are more widely applied in high temperature environments, and the temperature-dependent properties of the LTCC material play an important role in measurements of the characteristics of these devices at high temperature. In this paper, the temperature-dependence of the relative permittivity of DuPont 951 LTCC ceramic is studied from room temperature to 500 °C. An expression for relative permittivity is obtained, which relates the relative permittivity to the resonant frequency, inductance, parasitic capacitance and electrode capacitance of the LTCC sample. Of these properties, the electrode capacitance is the most strongly temperature-dependent. The LTCC sample resonant frequency, inductance and parasitic capacitance were measured (from room temperature to 500 °C with a high temperature measurement system comprising a muffle furnace and network analyzer. We found that the resonant frequency reduced and the inductance and parasitic capacitance increased slightly as the temperature increases. The relative permittivity can be calculated from experimental frequency, inductance and parasitic capacitance measurements. Calculating results show that the relative permittivity of DuPont 951 LTCC ceramic ceramic increases to 8.21 from room temperature to 500 °C.

  4. Thermocouple design for measuring temperatures of small insects

    Science.gov (United States)

    A.A. Hanson; R.C. Venette

    2013-01-01

    Contact thermocouples often are used to measure surface body temperature changes of insects during cold exposure. However, small temperature changes of minute insects can be difficult to detect, particularly during the measurement of supercooling points. We developed two thermocouple designs, which use 0.51 mm diameter or 0.127 mm diameter copper-constantan wires, to...

  5. Diagnostic accuracy of routine postoperative body temperature measurements

    NARCIS (Netherlands)

    Vermeulen, Hester; Storm-Versloot, Marja N.; Goossens, Astrid; Speelman, Peter; Legemate, Dink A.

    2005-01-01

    BACKGROUND: On surgical wards, body temperature is routinely measured, but there is no proof that this is useful for detecting postoperative infection. The aim of this study was to compare temperature measurements (the test) with the confirmed absence or presence of a postoperative infection (the

  6. Hysteresis and Temperature Dependency of Moisture Sorption – New Measurements

    DEFF Research Database (Denmark)

    Rode, Carsten; Hansen, Kurt Kielsgaard

    2011-01-01

    measurements of hysteresis and temperature dependency of the moisture sorption characteristics of three different porous building materials: aerated concrete, cement paste and spruce. Scanning curves are measured for all three materials where periods with adsorption and desorption interrupt each other...... intermittently. For one of the materials, aerated concrete, the sorption curves are determined at three different temperatures....

  7. 40 CFR 89.325 - Engine intake air temperature measurement.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Engine intake air temperature measurement. 89.325 Section 89.325 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Test Equipment Provisions § 89.325 Engine intake air temperature measurement. (a) Engine intake air...

  8. Measuring transient high temperature thermal phenomena in hostile environment

    International Nuclear Information System (INIS)

    Brenden, B.B.; Hartman, J.S.; Reich, F.R.

    1980-01-01

    The design of equipment for measuring temperature and strain in a rapidly heated and pressurized cylinder of stainless steel is discussed. Simultaneous cinematography of the full circumference of the cylinder without interference with temperature and strain measurements is also illustrated. The integrated system uses a reflective chamber for the sample and requires careful consideration of the spectral energy distribution utilized by each instrument

  9. Solar cell junction temperature measurement of PV module

    KAUST Repository

    Huang, B.J.

    2011-02-01

    The present study develops a simple non-destructive method to measure the solar cell junction temperature of PV module. The PV module was put in the environmental chamber with precise temperature control to keep the solar PV module as well as the cell junction in thermal equilibrium with the chamber. The open-circuit voltage of PV module Voc is then measured using a short pulse of solar irradiation provided by a solar simulator. Repeating the measurements at different environment temperature (40-80°C) and solar irradiation S (200-1000W/m2), the correlation between the open-circuit voltage Voc, the junction temperature Tj, and solar irradiation S is derived.The fundamental correlation of the PV module is utilized for on-site monitoring of solar cell junction temperature using the measured Voc and S at a short time instant with open circuit. The junction temperature Tj is then determined using the measured S and Voc through the fundamental correlation. The outdoor test results show that the junction temperature measured using the present method, Tjo, is more accurate. The maximum error using the average surface temperature Tave as the junction temperature is 4.8 °C underestimation; while the maximum error using the present method is 1.3 °C underestimation. © 2010 Elsevier Ltd.

  10. Multi-channel temperature measurement system for automotive battery stack

    Science.gov (United States)

    Lewczuk, Radoslaw; Wojtkowski, Wojciech

    2017-08-01

    A multi-channel temperature measurement system for monitoring of automotive battery stack is presented in the paper. The presented system is a complete battery temperature measuring system for hybrid / electric vehicles that incorporates multi-channel temperature measurements with digital temperature sensors communicating through 1-Wire buses, individual 1-Wire bus for each sensor for parallel computing (parallel measurements instead of sequential), FPGA device which collects data from sensors and translates it for CAN bus frames. CAN bus is incorporated for communication with car Battery Management System and uses additional CAN bus controller which communicates with FPGA device through SPI bus. The described system can parallel measure up to 12 temperatures but can be easily extended in the future in case of additional needs. The structure of the system as well as particular devices are described in the paper. Selected results of experimental investigations which show proper operation of the system are presented as well.

  11. Quantification of in situ temperature measurements on a PBI-based high temperature PEMFC unit cell

    DEFF Research Database (Denmark)

    Lebæk, Jesper; Ali, Syed Talat; Møller, Per

    2010-01-01

    The temperature is a very important operating parameter for all types of fuel cells. In the present work distributed in situ temperature measurements are presented on a polybenzimidazole based high temperature PEM fuel cell (HT-PEM). A total of 16 T-type thermocouples were embedded on both the an...

  12. Liquidus temperature and optical properties measurement by containerless techniques

    Science.gov (United States)

    Anderson, Collin D.

    1993-01-01

    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.

  13. How is it possible to measure a nuclear temperature

    International Nuclear Information System (INIS)

    Tamain, B.

    1989-01-01

    Several methods for the measurement of nuclear temperatures are summarized. The concepts of hot nuclei and temperature are defined. The nuclear equation of state is presented. The statistical theory of hot nuclei decay properties is analyzed. The obtention of the excitation energy from the recoil velocity measurement is considered in the case of complete and incomplete fusion. The measurements of temperature and excitation energy from the properties of decay products are reviewed. The study shows that no measurement method is perfect. Moreover, it is necessary to select events for which the degree of dissipation of the incident energy is estimated

  14. Outdoor surface temperature measurement: ground truth or lie?

    Science.gov (United States)

    Skauli, Torbjorn

    2004-08-01

    Contact surface temperature measurement in the field is essential in trials of thermal imaging systems and camouflage, as well as for scene modeling studies. The accuracy of such measurements is challenged by environmental factors such as sun and wind, which induce temperature gradients around a surface sensor and lead to incorrect temperature readings. In this work, a simple method is used to test temperature sensors under conditions representative of a surface whose temperature is determined by heat exchange with the environment. The tested sensors are different types of thermocouples and platinum thermistors typically used in field trials, as well as digital temperature sensors. The results illustrate that the actual measurement errors can be much larger than the specified accuracy of the sensors. The measurement error typically scales with the difference between surface temperature and ambient air temperature. Unless proper care is taken, systematic errors can easily reach 10% of this temperature difference, which is often unacceptable. Reasonably accurate readings are obtained using a miniature platinum thermistor. Thermocouples can perform well on bare metal surfaces if the connection to the surface is highly conductive. It is pointed out that digital temperature sensors have many advantages for field trials use.

  15. Measuring temperatures with modified Kleiber 270B pyrometer

    International Nuclear Information System (INIS)

    Osch, E.V. van.

    1995-05-01

    At ECN a fast pyrometer is being used as a diagnostic tool for plasma disruption simulation experiments on candidate plasma facing materials for future thermonuclear fusion devices such as NET or ITER. The pyrometer is being used to measure the surface temperature response of the materials to short pulse high heat loads as induced by high power laser or electron beam, simulating the disrupting plasma's energy deposition. A procedure to measure surface temperatures without having to know surface emissivity in advance is described. The formulae needed in this procedure to obtain the correct temperature, starting from the initial incorrect temperature reading, are derived. Inversely, the formula to determine the emissivity of the surface when its temperature is known is equally derived. Finally, a small study on background level sensitivity is presented, showing the, in general, small effect of background on the temperature measurement. (orig.)

  16. Measured gas and particle temperatures in VTT's entrained flow reactor

    DEFF Research Database (Denmark)

    Clausen, Sønnik; Sørensen, L.H.

    2006-01-01

    Particle and gas temperature measurements were carried out in experiments on VTTs entrained flow reactor with 5% and 10% oxygen using Fourier transform infrared emission spectroscopy (FTIR). Particle temperature measurements were performed on polish coal,bark, wood, straw particles, and bark...... and wood particles treated with additive. A two-color technique with subtraction of the background light was used to estimate particle temperatures during experiments. A transmission-emission technique was used tomeasure the gas temperature in the reactor tube. Gas temperature measurements were in good...... agreement with thermocouple readings. Gas lines and bands from CO, CO2 and H2O can be observed in the spectra. CO was only observed at the first measuring port (100ms) with the strongest CO-signal seen during experiments with straw particles. Variations in gas concentration (CO2 and H2O) and the signal from...

  17. Common rectifier diodes in temperature measurement applications below 50 K

    International Nuclear Information System (INIS)

    Jaervelae, J; Stenvall, A; Mikkonen, R

    2010-01-01

    In this paper we studied the use of common electronic semiconductor diodes in temperature measurements at cryogenic atmosphere. The motivation for this is the high price of calibrated cryogenic temperature sensors since there are some applications, like quench detection, in which a cheaper and a less accurate sensor would suffice. We measured the forward voltage as a function of temperature, V f (T), of several silicon rectifier diodes to determine the accuracy and interchangeability of the diodes. The experimental results confirmed that V f (T) of common rectifier diodes are similar to cryogenic sensor diodes, but the variability between two samples is much larger. The interchangeability of the diodes proved to be poor if absolute temperatures are to be measured. However for sensing changes in temperature they proved to be adequate and thus can be used to measure e.g. quench propagation or sense quench ignition at multiple locations with cheap price.

  18. Measurements of temperature profiles at the exit of small rockets.

    Science.gov (United States)

    Griggs, M; Harshbarger, F C

    1966-02-01

    The sodium line reversal technique was used to determine the reversal temperature profile across the exit of small rockets. Measurements were made on one 73-kg thrust rocket, and two 23-kg thrust rockets with different injectors. The large rocket showed little variation of reversal temperature across the plume. However, the 23-kg rockets both showed a large decrease of reversal temperature from the axis to the edge of the plume. In addition, the sodium line reversal technique of temperature measurement was compared with an infrared technique developed in these laboratories.

  19. Analysis and improvement of gas turbine blade temperature measurement error

    International Nuclear Information System (INIS)

    Gao, Shan; Wang, Lixin; Feng, Chi; Daniel, Ketui

    2015-01-01

    Gas turbine blade components are easily damaged; they also operate in harsh high-temperature, high-pressure environments over extended durations. Therefore, ensuring that the blade temperature remains within the design limits is very important. In this study, measurement errors in turbine blade temperatures were analyzed, taking into account detector lens contamination, the reflection of environmental energy from the target surface, the effects of the combustion gas, and the emissivity of the blade surface. In this paper, each of the above sources of measurement error is discussed, and an iterative computing method for calculating blade temperature is proposed. (paper)

  20. Analysis and improvement of gas turbine blade temperature measurement error

    Science.gov (United States)

    Gao, Shan; Wang, Lixin; Feng, Chi; Daniel, Ketui

    2015-10-01

    Gas turbine blade components are easily damaged; they also operate in harsh high-temperature, high-pressure environments over extended durations. Therefore, ensuring that the blade temperature remains within the design limits is very important. In this study, measurement errors in turbine blade temperatures were analyzed, taking into account detector lens contamination, the reflection of environmental energy from the target surface, the effects of the combustion gas, and the emissivity of the blade surface. In this paper, each of the above sources of measurement error is discussed, and an iterative computing method for calculating blade temperature is proposed.

  1. Application of phosphor thermometry to a Galvanneal Temperature Measurement System

    International Nuclear Information System (INIS)

    Allison, S.W.; Andrews, W.H.; Beshears, D.L.; Cates, M.R.; Childs, R.M.; Grann, E.B.; Manges, W.W.; McIntyre, T.J.; Scudiere, M.B.; Simpson, M.L.

    1999-01-01

    The Galvanneal Temperature Measurement System (GTMS) was developed for the American Iron and Steel Institute by the Oak Ridge National Laboratory through a partnership with the National Steel Midwest Division in Portage, Indiana. The GTMS provides crucial on-line thermal process control information during the manufacturing of galvanneal steel. The system has been used with the induction furnaces to measure temperatures ranging from 450 to 700 degrees C with an accuracy of better than +/-5 Degrees C. The GTMS provides accurate, reliable temperature information thus ensuring a high quality product, reducing waste, and saving energy. The production of uniform, high-quality galvanneal steel is only possible through strict temperature control

  2. Working memory capacity and redundant information processing efficiency.

    Science.gov (United States)

    Endres, Michael J; Houpt, Joseph W; Donkin, Chris; Finn, Peter R

    2015-01-01

    Working memory capacity (WMC) is typically measured by the amount of task-relevant information an individual can keep in mind while resisting distraction or interference from task-irrelevant information. The current research investigated the extent to which differences in WMC were associated with performance on a novel redundant memory probes (RMP) task that systematically varied the amount of to-be-remembered (targets) and to-be-ignored (distractor) information. The RMP task was designed to both facilitate and inhibit working memory search processes, as evidenced by differences in accuracy, response time, and Linear Ballistic Accumulator (LBA) model estimates of information processing efficiency. Participants (N = 170) completed standard intelligence tests and dual-span WMC tasks, along with the RMP task. As expected, accuracy, response-time, and LBA model results indicated memory search and retrieval processes were facilitated under redundant-target conditions, but also inhibited under mixed target/distractor and redundant-distractor conditions. Repeated measures analyses also indicated that, while individuals classified as high (n = 85) and low (n = 85) WMC did not differ in the magnitude of redundancy effects, groups did differ in the efficiency of memory search and retrieval processes overall. Results suggest that redundant information reliably facilitates and inhibits the efficiency or speed of working memory search, and these effects are independent of more general limits and individual differences in the capacity or space of working memory.

  3. High precision redundant robotic manipulator

    International Nuclear Information System (INIS)

    Young, K.K.D.

    1998-01-01

    A high precision redundant robotic manipulator for overcoming contents imposed by obstacles or imposed by a highly congested work space is disclosed. One embodiment of the manipulator has four degrees of freedom and another embodiment has seven degrees of freedom. Each of the embodiments utilize a first selective compliant assembly robot arm (SCARA) configuration to provide high stiffness in the vertical plane, a second SCARA configuration to provide high stiffness in the horizontal plane. The seven degree of freedom embodiment also utilizes kinematic redundancy to provide the capability of avoiding obstacles that lie between the base of the manipulator and the end effector or link of the manipulator. These additional three degrees of freedom are added at the wrist link of the manipulator to provide pitch, yaw and roll. The seven degrees of freedom embodiment uses one revolute point per degree of freedom. For each of the revolute joints, a harmonic gear coupled to an electric motor is introduced, and together with properly designed based servo controllers provide an end point repeatability of less than 10 microns. 3 figs

  4. Optimization of robustness of interdependent network controllability by redundant design.

    Directory of Open Access Journals (Sweden)

    Zenghu Zhang

    Full Text Available Controllability of complex networks has been a hot topic in recent years. Real networks regarded as interdependent networks are always coupled together by multiple networks. The cascading process of interdependent networks including interdependent failure and overload failure will destroy the robustness of controllability for the whole network. Therefore, the optimization of the robustness of interdependent network controllability is of great importance in the research area of complex networks. In this paper, based on the model of interdependent networks constructed first, we determine the cascading process under different proportions of node attacks. Then, the structural controllability of interdependent networks is measured by the minimum driver nodes. Furthermore, we propose a parameter which can be obtained by the structure and minimum driver set of interdependent networks under different proportions of node attacks and analyze the robustness for interdependent network controllability. Finally, we optimize the robustness of interdependent network controllability by redundant design including node backup and redundancy edge backup and improve the redundant design by proposing different strategies according to their cost. Comparative strategies of redundant design are conducted to find the best strategy. Results shows that node backup and redundancy edge backup can indeed decrease those nodes suffering from failure and improve the robustness of controllability. Considering the cost of redundant design, we should choose BBS (betweenness-based strategy or DBS (degree based strategy for node backup and HDF(high degree first for redundancy edge backup. Above all, our proposed strategies are feasible and effective at improving the robustness of interdependent network controllability.

  5. Body Temperature Measurements for Metabolic Phenotyping in Mice

    Science.gov (United States)

    Meyer, Carola W.; Ootsuka, Youichirou; Romanovsky, Andrej A.

    2017-01-01

    Endothermic organisms rely on tightly balanced energy budgets to maintain a regulated body temperature and body mass. Metabolic phenotyping of mice, therefore, often includes the recording of body temperature. Thermometry in mice is conducted at various sites, using various devices and measurement practices, ranging from single-time probing to continuous temperature imaging. Whilst there is broad agreement that body temperature data is of value, procedural considerations of body temperature measurements in the context of metabolic phenotyping are missing. Here, we provide an overview of the various methods currently available for gathering body temperature data from mice. We explore the scope and limitations of thermometry in mice, with the hope of assisting researchers in the selection of appropriate approaches, and conditions, for comprehensive mouse phenotypic analyses. PMID:28824441

  6. Electronic temperature control and measurements reactor fuel rig circuits

    Energy Technology Data Exchange (ETDEWEB)

    Glowacki, S W

    1980-01-01

    The electronic circuits of two digital temperature meters developed for the thermocouple of Ni-NiCr type are described. The output thermocouple signal as converted by means of voltage-to-freguency converter. The frequency is measured by a digital scaler controled by quartz generator signals. One of the described meter is coupled with digital temperature controler which drives the power stage of the reactor rig heater. The internal rig temperature is measured by the thermocouple providing the input signal to the mentioned voltage-to-frequency converter, that means the circuits work in the negative feedback loop. The converter frequency-to-voltage ratio is automatically adjusted to match to thermocouple sensitivity changes in the course of the temperature variations. The accuracy of measuring system is of order of +- 1degC for thermocouple temperature changes from 523 K up to 973 K (50degC up to 700degC).

  7. The electronic temperature control and measurements reactor fuel rig circuits

    International Nuclear Information System (INIS)

    Glowacki, S.W.

    1980-01-01

    The electronic circuits of two digital temperature meters developed for the thermocouple of Ni-NiCr type are described. The output thermocouple signal as converted by means of voltage-to-freguency converter. The frequency is measured by a digital scaler controled by quartz generator signals. One of the described meter is coupled with digital temperature controler which drives the power stage of the reactor rig heater. The internal rig temperature is measured by the thermocouple providing the input signal to the mentioned voltage-to-frequency converter, that means the circuits work in the negative feedback loop. The converter frequency-to-voltage ratio is automatically adjusted to match to thermocouple sensitivity changes in the course of the temperature variations. The accuracy of measuring system is of order of +- 1degC for thermocouple temperature changes from 523 K up to 973 K (50degC up to 700degC). (author)

  8. Temperature measurement in low pressure plasmas. Temperaturmessungen im Niederdruckplasma

    Energy Technology Data Exchange (ETDEWEB)

    Rosenbauer, K.A.; Wilting, H.; Schramm, G. (Duesseldorf Univ. (Germany, F.R.). Abt. fuer Histologie und Embryologie)

    1989-11-01

    The present work discusses the influence of various parameters on the substrate temperature in a low pressure plasma. The measurement method chosen utilized Signotherm (Merck) temperature sensors embedded in silicon between two glass substrates. All measurements were made in a 200 G Plasma Processor from Technics Plasma GmbH. The substrate temperature is dependent on the process time, the RF power, the process gas and the position in the chamber. The substrate temperature increases with increasing process time and increasing power. Due to the location of the microwave port from the magnetron to the chamber, the substrate temperature is highest in the center of the chamber. Measurements performed in an air plasma yielded higher results than in an oxygen plasma. (orig.).

  9. Technology and education: First approach for measuring temperature with Arduino

    Science.gov (United States)

    Carrillo, Alejandro

    2017-04-01

    This poster session presents some ideas and approaches to understand concepts of thermal equilibrium, temperature and heat in order to bulid a man-nature relationship in a harmonious and responsible manner, emphasizing the interaction between science and technology, without neglecting the relationship of the environment and society, an approach to sustainability. It is proposed the development of practices that involve the use of modern technology, of easy access and low cost to measure temperature. We believe that the Arduino microcontroller and some temperature sensors can open the doors of innovation to carry out such practices. In this work we present some results of simple practices presented to a population of students between the ages of 16 and 17 years old. The practices in this proposal are: Zero law of thermodynamics and the concept of temperature, calibration of thermometers and measurement of temperature for heating and cooling of three different substances under the same physical conditions. Finally the student is asked to make an application that involves measuring of temperature and other physical parameters. Some suggestions are: to determine the temperature at which we take some food, measure the temperature difference at different rooms of a house, housing constructions that favour optimal condition, measure the temperature of different regions, measure of temperature trough different colour filters, solar activity and UV, propose applications to understand current problems such as global warming, etc. It is concluded that the Arduino practices and electrical sensors increase the cultural horizon of the students while awaking their interest to understand their operation, basic physics and its application from a modern perspective.

  10. Solar cell junction temperature measurement of PV module

    KAUST Repository

    Huang, B.J.; Yang, P.E.; Lin, Y.P.; Lin, B.Y.; Chen, H.J.; Lai, R.C.; Cheng, J.S.

    2011-01-01

    The present study develops a simple non-destructive method to measure the solar cell junction temperature of PV module. The PV module was put in the environmental chamber with precise temperature control to keep the solar PV module as well

  11. Spectroscopic analysis applied to temperature measurement in plasmas

    International Nuclear Information System (INIS)

    Fieffe-Prevost, P.

    1978-01-01

    The plasma temperature is defined only if the plasma is in a state near thermodynamic equilibrium. This plasma state is analysed in detail and spectroscopic methods for measuring the temperature are discussed. As an application the hydrogen arc of the National Institute of Metrology of the Conservatoire National des Arts et Metiers (Paris) is briefly described [fr

  12. Refractory thermowell for continuous high temperature measurement of molten metal

    International Nuclear Information System (INIS)

    Thiesen, T.J.

    1992-01-01

    This patent describes a vessel for handling molten metal having an interior refractory lining, apparatus for continuous high temperature measurement of the molten metal. It comprises a thermowell; the thermowell containing a multiplicity of thermocouples; leads being coupled to a means for continuously indicating the temperature of the molten metal in the vessel

  13. Miniature ingestible telemeter devices to measure deep-body temperature

    Science.gov (United States)

    Pope, J. M.; Fryer, T. B. (Inventor)

    1976-01-01

    A telemetry device comprised of a pill-size ingestible transmitter developed to obtain deep body temperature measurements of a human is described. The device has particular utility in the medical field where deep body temperatures provide an indication of general health.

  14. Time-Resolved Surface Temperature Measurement for Pulsed Ablative Thrusters

    National Research Council Canada - National Science Library

    Antonsen, Erik

    2003-01-01

    .... The diagnostic draws on heritage from the experimental dynamic crack propagation community which has used photovoltaic infrared detectors to measure temperature rise in materials in the process of fracture...

  15. Device for measuring the temperature of flowing hot gases

    Energy Technology Data Exchange (ETDEWEB)

    Reed, R D

    1977-05-12

    The invention pertains to a device to measure the temperature of a hot gas flowing through a closed tube. The device will have a simple and inexpensive design and avoid heat losses due to heat radiation near the thermal sensor.

  16. High temperature spectral emissivity measurement using integral blackbody method

    Science.gov (United States)

    Pan, Yijie; Dong, Wei; Lin, Hong; Yuan, Zundong; Bloembergen, Pieter

    2016-10-01

    Spectral emissivity is a critical material's thermos-physical property for heat design and radiation thermometry. A prototype instrument based upon an integral blackbody method was developed to measure material's spectral emissivity above 1000 °. The system was implemented with an optimized commercial variable-high-temperature blackbody, a high speed linear actuator, a linear pyrometer, and an in-house designed synchronization circuit. A sample was placed in a crucible at the bottom of the blackbody furnace, by which the sample and the tube formed a simulated blackbody which had an effective total emissivity greater than 0.985. During the measurement, the sample was pushed to the end opening of the tube by a graphite rod which was actuated through a pneumatic cylinder. A linear pyrometer was used to monitor the brightness temperature of the sample surface through the measurement. The corresponding opto-converted voltage signal was fed and recorded by a digital multi-meter. A physical model was proposed to numerically evaluate the temperature drop along the process. Tube was discretized as several isothermal cylindrical rings, and the temperature profile of the tube was measurement. View factors between sample and rings were calculated and updated along the whole pushing process. The actual surface temperature of the sample at the end opening was obtained. Taking advantages of the above measured voltage profile and the calculated true temperature, spectral emissivity under this temperature point was calculated.

  17. Improving the spectral measurement accuracy based on temperature distribution and spectra-temperature relationship

    Science.gov (United States)

    Li, Zhe; Feng, Jinchao; Liu, Pengyu; Sun, Zhonghua; Li, Gang; Jia, Kebin

    2018-05-01

    Temperature is usually considered as a fluctuation in near-infrared spectral measurement. Chemometric methods were extensively studied to correct the effect of temperature variations. However, temperature can be considered as a constructive parameter that provides detailed chemical information when systematically changed during the measurement. Our group has researched the relationship between temperature-induced spectral variation (TSVC) and normalized squared temperature. In this study, we focused on the influence of temperature distribution in calibration set. Multi-temperature calibration set selection (MTCS) method was proposed to improve the prediction accuracy by considering the temperature distribution of calibration samples. Furthermore, double-temperature calibration set selection (DTCS) method was proposed based on MTCS method and the relationship between TSVC and normalized squared temperature. We compare the prediction performance of PLS models based on random sampling method and proposed methods. The results from experimental studies showed that the prediction performance was improved by using proposed methods. Therefore, MTCS method and DTCS method will be the alternative methods to improve prediction accuracy in near-infrared spectral measurement.

  18. Wet method for measuring starch gelatinization temperature using electrical conductivity.

    Science.gov (United States)

    Morales-Sanchez, E; Figueroa, J D C; Gaytan-Martínez, M

    2009-09-01

    The objective of the present study was to develop a method for obtaining the gelatinization temperature of starches by using electrical conductivity. Native starches from corn, rice, potato, and wheat were prepared with different proportions of water and heated from room temperature to 90 degrees C, in a device especially designed for monitoring the electrical conductivity as a function of temperature. The results showed a linear trend of the electrical conductivity with the temperature until it reaches the onset gelatinization temperature. After that point, the electrical conductivity presented an increment or decrement depending on the water content in the sample and it was related to starch swelling and gelatinization phenomena. At the end gelatinization temperature, the conductivity becomes stable and linear, indicating that there are no more changes of phase. The starch gelatinization parameter, which was evaluated in the 4 types of starches using the electrical conductivity, was compared with those obtained by using differential scanning calorimeter (DSC). The onset temperature at which the electrical conductivity increased or decreased was found to be similar to that obtained by DSC. Also, the final temperature at which the electrical conductivity returned to linearity matched the end gelatinization temperature of the DSC. Further, a wet method for measuring the onset, peak, and end gelatinization temperatures as a function of temperature using the electrical conductivity curves is presented for a starch-water suspension.

  19. Measurement of the temperature distribution inside the power cable using distributed temperature system

    Science.gov (United States)

    Jaros, Jakub; Liner, Andrej; Papes, Martin; Vasinek, Vladimir; Mach, Veleslav; Hruby, David; Kajnar, Tomas; Perecar, Frantisek

    2015-01-01

    Nowadays, the power cables are manufactured to fulfill the following condition - the highest allowable temperature of the cable during normal operation and the maximum allowable temperature at short circuit conditions cannot exceed the condition of the maximum allowable internal temperature. The distribution of the electric current through the conductor leads to the increase of the amplitude of electrons in the crystal lattice of the cables material. The consequence of this phenomenon is the increase of friction and the increase of collisions between particles inside the material, which causes the temperature increase of the carrying elements. The temperature increase is unwanted phenomena, because it is causing losses. In extreme cases, the long-term overload leads to the cable damaging or fire. This paper deals with the temperature distribution measurement inside the power cables using distributed temperature system. With cooperation with Kabex company, the tube containing optical fibers was installed into the center of power cables. These fibers, except telecommunications purposes, can be also used as sensors in measurements carrying out with distributed temperature system. These systems use the optical fiber as a sensor and allow the continual measurement of the temperature along the whole cable in real time with spatial resolution 1 m. DTS systems are successfully deployed in temperature measurement applications in industry areas yet. These areas include construction, drainage, hot water etc. Their advantages are low cost, resistance to electromagnetic radiation and the possibility of real time monitoring at the distance of 8 km. The location of the optical fiber in the center of the power cable allows the measurement of internal distribution of the temperature during overloading the cable. This measurement method can be also used for prediction of short-circuit and its exact location.

  20. The effects of spatial sampling choices on MR temperature measurements.

    Science.gov (United States)

    Todd, Nick; Vyas, Urvi; de Bever, Josh; Payne, Allison; Parker, Dennis L

    2011-02-01

    The purpose of this article is to quantify the effects that spatial sampling parameters have on the accuracy of magnetic resonance temperature measurements during high intensity focused ultrasound treatments. Spatial resolution and position of the sampling grid were considered using experimental and simulated data for two different types of high intensity focused ultrasound heating trajectories (a single point and a 4-mm circle) with maximum measured temperature and thermal dose volume as the metrics. It is demonstrated that measurement accuracy is related to the curvature of the temperature distribution, where regions with larger spatial second derivatives require higher resolution. The location of the sampling grid relative temperature distribution has a significant effect on the measured values. When imaging at 1.0 × 1.0 × 3.0 mm(3) resolution, the measured values for maximum temperature and volume dosed to 240 cumulative equivalent minutes (CEM) or greater varied by 17% and 33%, respectively, for the single-point heating case, and by 5% and 18%, respectively, for the 4-mm circle heating case. Accurate measurement of the maximum temperature required imaging at 1.0 × 1.0 × 3.0 mm(3) resolution for the single-point heating case and 2.0 × 2.0 × 5.0 mm(3) resolution for the 4-mm circle heating case. Copyright © 2010 Wiley-Liss, Inc.

  1. Temperature measurement in the adult emergency department: oral, tympanic membrane and temporal artery temperatures versus rectal temperature.

    Science.gov (United States)

    Bijur, Polly E; Shah, Purvi D; Esses, David

    2016-12-01

    The objective was to compare agreement between three non-invasive measures of temperature and rectal temperatures and to estimate the sensitivity and specificity of these measures to detect a rectal temperature of 38°C or higher. We conducted a study of the diagnostic accuracy of oral, tympanic membrane (TM) and temporal artery (TA) thermometry to measure fever in an urban emergency department (ED). Data were collected from adult patients who received rectal temperature measurement. Bland-Altman analysis was performed; sensitivity, specificity and 95% CIs were calculated. 987 patients were enrolled. 36% of the TM and TA readings differed by 0.5°C or more from rectal temperatures, 50% of oral temperatures. TM measures were most precise-the SD of the difference from rectal was 0.4°C TM, and 0.6°C for oral and TA (ptemperature of 38°C or higher were: 37.0%, 68.3% and 71.1%, respectively (oral vs TM and TA pmethods (pmethods met benchmarks for diagnostic accuracy using the criterion of 38°C to detect rectal temperature of 38°C. A TM cutpoint of 37.5°C provides maximum diagnostic accuracy of the three non-invasive measures. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  2. Ring to measure magnetic permeability at cryogenic temperatures

    CERN Multimedia

    1977-01-01

    While for magn. permeability measurements at room temperature a split-coil permeameter is used (see photo 7708553X), for measurements at cryogenic temperatures the excitation and the flux-measuring coils are wound directly on the ring sample by means of a toroidal winding machine. The ring in the picture was made to select the mild steel for the ISR Prototype Superconducting Quadrupole(see photo 7702690X). The excitation coil was wound with 1 mm diam. copper wire and had about 2730 turns. For measurements at 4.2 K a max. current of 90 A was used. See also photos 7708553X,7708100,7708103.

  3. Dielectric properties measurement system at cryogenic temperatures and microwave frequencies

    Energy Technology Data Exchange (ETDEWEB)

    Molla, J.; Ibarra, A.; Margineda, J.; Zamarro, J. M.; Hernandez, A.

    1994-07-01

    A system based on the resonant cavity method has been developed to measure the permittivity and loss tangent at 12-18 GHz over the temperature range 80 K to 300 K. Changes of permittivity as low as 0.01 % in the range 1 to 30, and 3 x 10{sup 6} for loss tangent values below 10{sup 2}, can be obtained without requiring temperature stability. The thermal expansion coefficient and resistivity factor of copper have been measured between 80 K and 300 K. Permittivity of sapphire and loss tangent of alumina of 99.9 % purity in the same temperature range are presented. (Author) 23 refs.

  4. Dielectric properties measurement system at cryogenic temperatures and microwave frequencies

    International Nuclear Information System (INIS)

    Molla, J.; Ibarra, A.; Margineda, J.; Zamarro, J.M.; Hernandez, A.

    1994-01-01

    A system based on the resonant cavity method has been developed to measure the permittivity and loss tangent at 12-18 GHz over the temperature range 80 K to 300 K. Changes of permittivity as low as 0.01% in the range 1 to 30, and 3 x 10''6 for loss tangent values below 10''2, can be obtained without requiring temperature stability. The thermal expansion coefficient and resistivity factor of copper have been measured between 80 K and 300 K. Permittivity of sapphire and loss tangent of alumina of 99,9% purity in the same temperature range are presented

  5. Influence of temperature to quenching on liquid scintillation measurement

    CERN Document Server

    Kato, T

    2003-01-01

    The amount of quench is measured with liquid scintillation spectrometer changing the temperature of the sample. The range of the changed temperature is between 0 deg C and 35 deg C. The measurement is carried out for three kinds of unquenched standard, two quenched standards and fifteen kinds of scintillation cocktail and the mixed sample. It is confirmed that the amount of quench increases for all samples as the temperature rises. The influence of the changed amount of quench to the quench correction is examined. (author)

  6. Fiber Bragg Grating Based System for Temperature Measurements

    Science.gov (United States)

    Tahir, Bashir Ahmed; Ali, Jalil; Abdul Rahman, Rosly

    In this study, a fiber Bragg grating sensor for temperature measurement is proposed and experimentally demonstrated. In particular, we point out that the method is well-suited for monitoring temperature because they are able to withstand a high temperature environment, where standard thermocouple methods fail. The interrogation technologies of the sensor systems are all simple, low cost and effective as well. In the sensor system, fiber grating was dipped into a water beaker that was placed on a hotplate to control the temperature of water. The temperature was raised in equal increments. The sensing principle is based on tracking of Bragg wavelength shifts caused by the temperature change. So the temperature is measured based on the wavelength-shifts of the FBG induced by the heating water. The fiber grating is high temperature stable excimer-laser-induced grating and has a linear function of wavelength-temperature in the range of 0-285°C. A dynamic range of 0-285°C and a sensitivity of 0.0131 nm/°C almost equal to that of general FBG have been obtained by this sensor system. Furthermore, the correlation of theoretical analysis and experimental results show the capability and feasibility of the purposed technique.

  7. Multi-spectral temperature measurement method for gas turbine blade

    Science.gov (United States)

    Gao, Shan; Feng, Chi; Wang, Lixin; Li, Dong

    2016-02-01

    One of the basic methods to improve both the thermal efficiency and power output of a gas turbine is to increase the firing temperature. However, gas turbine blades are easily damaged in harsh high-temperature and high-pressure environments. Therefore, ensuring that the blade temperature remains within the design limits is very important. There are unsolved problems in blade temperature measurement, relating to the emissivity of the blade surface, influences of the combustion gases, and reflections of radiant energy from the surroundings. In this study, the emissivity of blade surfaces has been measured, with errors reduced by a fitting method, influences of the combustion gases have been calculated for different operational conditions, and a reflection model has been built. An iterative computing method is proposed for calculating blade temperatures, and the experimental results show that this method has high precision.

  8. Measuring gas temperature during spin-exchange optical pumping process

    Science.gov (United States)

    Normand, E.; Jiang, C. Y.; Brown, D. R.; Robertson, L.; Crow, L.; Tong, X.

    2016-04-01

    The gas temperature inside a Spin-Exchange Optical Pumping (SEOP) laser-pumping polarized 3He cell has long been a mystery. Different experimental methods were employed to measure this temperature but all were based on either modelling or indirect measurement. To date there has not been any direct experimental measurement of this quantity. Here we present the first direct measurement using neutron transmission to accurately determine the number density of 3He, the temperature is obtained using the ideal gas law. Our result showed a surprisingly high gas temperature of 380°C, compared to the 245°C of the 3He cell wall temperature and 178°C of the optical pumping oven temperature. This experiment result may be used to further investigate the unsolved puzzle of the "X-factor" in the SEOP process which places an upper bound to the 3He polarization that can be achieved. Additional spin relaxation mechanisms might exist due to the high gas temperature, which could explain the origin of the X-factor.

  9. Technical note: Using distributed temperature sensing for Bowen ratio evaporation measurements

    Science.gov (United States)

    Schilperoort, Bart; Coenders-Gerrits, Miriam; Luxemburg, Willem; Jiménez Rodríguez, César; Cisneros Vaca, César; Savenije, Hubert

    2018-01-01

    Rapid improvements in the precision and spatial resolution of distributed temperature sensing (DTS) technology now allow its use in hydrological and atmospheric sciences. Introduced by ) is the use of DTS for measuring the Bowen ratio (BR-DTS), to estimate the sensible and latent heat flux. The Bowen ratio is derived from DTS-measured vertical profiles of the air temperature and wet-bulb temperature. However, in previous research the measured temperatures were not validated, and the cables were not shielded from solar radiation. Additionally, the BR-DTS method has not been tested above a forest before, where temperature gradients are small and energy storage in the air column becomes important. In this paper the accuracy of the wet-bulb and air temperature measurements of the DTS are verified, and the resulting Bowen ratio and heat fluxes are compared to eddy covariance data. The performance of BR-DTS was tested on a 46 m high tower in a mixed forest in the centre of the Netherlands in August 2016. The average tree height is 26 to 30 m, and the temperatures are measured below, in, and above the canopy. Using the vertical temperature profiles the storage of latent and sensible heat in the air column was calculated. We found a significant effect of solar radiation on the temperature measurements, leading to a deviation of up to 3 K. By installing screens, the error caused by sunlight is reduced to under 1 K. Wind speed seems to have a minimal effect on the measured wet-bulb temperature, both below and above the canopy. After a simple quality control, the Bowen ratio measured by DTS correlates well with eddy covariance (EC) estimates (r2 = 0.59). The average energy balance closure between BR-DTS and EC is good, with a mean underestimation of 3.4 W m-2 by the BR-DTS method. However, during daytime the BR-DTS method overestimates the available energy, and during night-time the BR-DTS method estimates the available energy to be more negative. This difference could be

  10. Continuous Emission Spectrum Measurement for Electron Temperature Determination in Low-Temperature Collisional Plasmas

    International Nuclear Information System (INIS)

    Liu Qiuyan; Li Hong; Chen Zhipeng; Xie Jinlin; Liu Wandong

    2011-01-01

    Continuous emission spectrum measurement is applied for the inconvenient diagnostics of low-temperature collisional plasmas. According to the physical mechanism of continuous emission, a simplified model is presented to analyze the spectrum in low temperature plasma. The validity of this model is discussed in a wide range of discharge parameters, including electron temperature and ionization degree. Through the simplified model, the continuous emission spectrum in a collisional argon internal inductively coupled plasma is experimentally measured to determine the electron temperature distribution for different gas pressures and radio-frequency powers. The inverse Abel transform is also applied for a better spatially resoluted results. Meanwhile, the result of the continuous emission spectrum measurement is compared to that of the electrostatic double probes, which indicates the effectiveness of this method. (low temperature plasma)

  11. Reliability Analysis and Calibration of Partial Safety Factors for Redundant Structures

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard

    1998-01-01

    Redundancy is important to include in the design and analysis of structural systems. In most codes of practice redundancy is not directly taken into account. In the paper various definitions of a deterministic and reliability based redundancy measure are reviewed. It is described how reundancy can...... be included in the safety system and how partial safety factors can be calibrated. An example is presented illustrating how redundancy is taken into account in the safety system in e.g. the Danish codes. The example shows how partial safety factors can be calibrated to comply with the safety level...

  12. Low-temperature mobility measurements on CMOS devices

    International Nuclear Information System (INIS)

    Hairpetian, A.; Gitlin, D.; Viswanathan, C.R.

    1989-01-01

    The surface channel mobility of carriers in eta- and rho-MOS transistors fabricated in a CMOS process was accurately determined at low temperatures down to 5 Κ. The mobility was obtained by an accurate measurement of the inversion charge density using a split C-V technique and the conductance at low drain voltages. The split C-V technique was validated at all temperatures using a one-dimensional Poisson solver (MOSCAP), which was modified for low-temperature application. The mobility dependence on the perpendicular electric field for different substrate bias values appears to have different temperature dependence for eta- and rho-channel devices. The electron mobility increases with a decrease in temperature at all gate voltages. On the other hand, the hole mobility exhibits a different temperature behavior depending upon whether the gate voltage corresponds to strong inversion or is near threshold

  13. Description of the universal low-temperature measuring system

    International Nuclear Information System (INIS)

    Langfeld, R.; Maurer, C.

    1987-01-01

    There are various measuring methods for a characterization of semiconductor devices, especially for analysis of radiation effects after ion implantation. The four most important methods are: 1. Recording of voltage-current characteristics at pn-junctions or Schottky diodes. 2. Determination of the temperature dependence of the electrical resistance, e.g. of amorphous semiconductor layers, by feeding a constant voltage and measuring the current as a function of sample temperature. 3. Measurement of the resistive layer capacitance of a semiconductor diode as a function of the fed blocking voltage and determination of the doping concentration profile. 4. Time-resolved capacitance measurement after abrupt blocking-voltage alterations at pn - or Schottky diodes as a function of specimen temperature for determining defects in semiconductors, DLTS method. A measuring equipment has been set up that allows measurements being made in the temperature range between 14 K and 400 K, on up to eight specimens in one temperature test. Operating mode and handling of the computerized measuring program are described. (orig./HP) [de

  14. Modern gas-based temperature and pressure measurements

    CERN Document Server

    Pavese, Franco

    2013-01-01

    This 2nd edition volume of Modern Gas-Based Temperature and Pressure Measurements follows the first publication in 1992. It collects a much larger set of information, reference data, and bibliography in temperature and pressure metrology of gaseous substances, including the physical-chemical issues related to gaseous substances. The book provides solutions to practical applications where gases are used in different thermodynamic conditions. Modern Gas-Based Temperature and Pressure Measurements, 2nd edition is the only comprehensive survey of methods for pressure measurement in gaseous media used in the medium-to-low pressure range closely connected with thermometry. It assembles current information on thermometry and manometry that involve the use of gaseous substances which are likely to be valid methods for the future. As such, it is an important resource for the researcher. This edition is updated through the very latest scientific and technical developments of gas-based temperature and pressure measurem...

  15. High temperature measurements of the microwave dielectric properties of ceramics

    International Nuclear Information System (INIS)

    Baeraky, T.A.

    1999-06-01

    Equipment has been developed for the measurement of dielectric properties at high temperature from 25 to 1700 deg. C in the microwave frequency range 614.97 to 3620.66 MHz using the cavity perturbation technique, to measure the permittivity of a range of ceramic materials. The complex permittivities of the standard materials, water and methanol, were measured at low temperature and compared with the other published data. A statistical analysis was made for the permittivity measurements of water and methanol using sample holders of different diameter. Also the measurements of these materials were used to compare the simple perturbation equation with its modifications and alternation correction methods for sample shape and the holes at the two endplates of the cavity. The dielectric properties of solid materials were investigated from the permittivity measurements on powder materials, shown in table 4.7, using the dielectric mixture equations. Two kinds of ceramics, oxide and nitrides, were selected for the high temperature dielectric measurements in microwave frequency ranges. Pure zirconia, yttria-stabilised zirconia, and Magnesia-stabilised zirconia are the oxide ceramics while aluminium nitride and silicon nitride are the nitride ceramics. A phase transformation from monoclinic to tetragonal was observed in pure zirconia in terms of the complex permittivity measurements, and the conduction mechanism in three regions of temperature was suggested to be ionic in the first region and a mixture of ionic and electronic in the second. The phase transition disappeared with yttria-stabilised zirconia but it was observed with magnesia-stabilised zirconia. Yttria doped zirconia was fully stabilised while magnesia stabilised was partially stabilised zirconia. The dielectric property measurements of aluminium nitride indicated that there is a transition from AIN to AlON, which suggested that the external layer of the AIN which was exposed to the air, contains alumina. It was

  16. Soil temperature variability in complex terrain measured using fiber-optic distributed temperature sensing

    Science.gov (United States)

    Soil temperature (Ts) exerts critical controls on hydrologic and biogeochemical processes but magnitude and nature of Ts variability in a landscape setting are rarely documented. Fiber optic distributed temperature sensing systems (FO-DTS) potentially measure Ts at high density over a large extent. ...

  17. A nonintrusive temperature measuring system for estimating deep body temperature in bed.

    Science.gov (United States)

    Sim, S Y; Lee, W K; Baek, H J; Park, K S

    2012-01-01

    Deep body temperature is an important indicator that reflects human being's overall physiological states. Existing deep body temperature monitoring systems are too invasive to apply to awake patients for a long time. Therefore, we proposed a nonintrusive deep body temperature measuring system. To estimate deep body temperature nonintrusively, a dual-heat-flux probe and double-sensor probes were embedded in a neck pillow. When a patient uses the neck pillow to rest, the deep body temperature can be assessed using one of the thermometer probes embedded in the neck pillow. We could estimate deep body temperature in 3 different sleep positions. Also, to reduce the initial response time of dual-heat-flux thermometer which measures body temperature in supine position, we employed the curve-fitting method to one subject. And thereby, we could obtain the deep body temperature in a minute. This result shows the possibility that the system can be used as practical temperature monitoring system with appropriate curve-fitting model. In the next study, we would try to establish a general fitting model that can be applied to all of the subjects. In addition, we are planning to extract meaningful health information such as sleep structure analysis from deep body temperature data which are acquired from this system.

  18. Design of a redundant meteorological station for a BWR reactor

    International Nuclear Information System (INIS)

    Ramirez S, R.; Celis del Angel, L.; Bucio, F.; Rivero, T.; Palacios, J.

    2008-01-01

    In this work the design of a meteorological station for a reactor type BWR is proposed. Two independent channels of data acquisition that allow him to have a bigger readiness is exposed. It is incorporate sensors without mobile parts to measure speed, wind direction and pluvial precipitation. It also counts, with sensors of global solar radiation, net radiation, barometric pressure, relative humidity and ambient temperature; with them they are possible to be calculated, moreover, other variables as temperature differential, dew point and atmospheric stability. The sensors are placed on a tower to different heights and send their information (each second) to a local registration system, the one which in turn, it remits the data to the monitoring office so that a computer is linked with the system, display and management the information in real time and automatic way. The redundant structure allows that in the event of maintenance the data acquisition is not interrupted, even if the information is transferred to another place. In all the station sections it is used protocols of standard communication to allow that a great quantity of devices can be connected without major problem. The above-mentioned would allow to the operators in the control room to have reliable information during the whole time of the reactor operation. (Author)

  19. X3 expansion tube driver gas spectroscopy and temperature measurements

    Science.gov (United States)

    Parekh, V.; Gildfind, D.; Lewis, S.; James, C.

    2017-11-01

    The University of Queensland's X3 facility is a large, free-piston driven expansion tube used for super-orbital and high Mach number scramjet aerothermodynamic studies. During recent development of new scramjet test flow conditions, experimentally measured shock speeds were found to be significantly lower than that predicted by initial driver performance calculations. These calculations were based on ideal, isentropic compression of the driver gas and indicated that loss mechanisms, not accounted for in the preliminary analysis, were significant. The critical determinant of shock speed is peak driver gas sound speed, which for a given gas composition depends on the peak driver gas temperature. This temperature may be inaccurately estimated if an incorrect fill temperature is assumed, or if heat losses during driver gas compression are significant but not accounted for. For this study, the ideal predicted peak temperature was 3750 K, without accounting for losses. However, a much lower driver temperature of 2400 K is suggested based on measured experimental shock speeds. This study aimed to measure initial and peak driver gas temperatures for a representative X3 operating condition. Examination of the transient temperatures of the driver gas and compression tube steel wall during the initial fill process showed that once the filling process was complete, the steady-state driver gas temperature closely matched the tube wall temperature. Therefore, while assuming the gas is initially at the ambient laboratory temperature is not a significant source of error, it can be entirely mitigated by simply monitoring tube wall temperature. Optical emission spectroscopy was used to determine the driver gas spectra after diaphragm rupture; the driver gas emission spectrum exhibited a significant continuum radiation component, with prominent spectral lines attributed to contamination of the gas. A graybody approximation of the continuum suggested a peak driver gas temperature of

  20. X3 expansion tube driver gas spectroscopy and temperature measurements

    Science.gov (United States)

    Parekh, V.; Gildfind, D.; Lewis, S.; James, C.

    2018-07-01

    The University of Queensland's X3 facility is a large, free-piston driven expansion tube used for super-orbital and high Mach number scramjet aerothermodynamic studies. During recent development of new scramjet test flow conditions, experimentally measured shock speeds were found to be significantly lower than that predicted by initial driver performance calculations. These calculations were based on ideal, isentropic compression of the driver gas and indicated that loss mechanisms, not accounted for in the preliminary analysis, were significant. The critical determinant of shock speed is peak driver gas sound speed, which for a given gas composition depends on the peak driver gas temperature. This temperature may be inaccurately estimated if an incorrect fill temperature is assumed, or if heat losses during driver gas compression are significant but not accounted for. For this study, the ideal predicted peak temperature was 3750 K, without accounting for losses. However, a much lower driver temperature of 2400 K is suggested based on measured experimental shock speeds. This study aimed to measure initial and peak driver gas temperatures for a representative X3 operating condition. Examination of the transient temperatures of the driver gas and compression tube steel wall during the initial fill process showed that once the filling process was complete, the steady-state driver gas temperature closely matched the tube wall temperature. Therefore, while assuming the gas is initially at the ambient laboratory temperature is not a significant source of error, it can be entirely mitigated by simply monitoring tube wall temperature. Optical emission spectroscopy was used to determine the driver gas spectra after diaphragm rupture; the driver gas emission spectrum exhibited a significant continuum radiation component, with prominent spectral lines attributed to contamination of the gas. A graybody approximation of the continuum suggested a peak driver gas temperature of

  1. Inverse analysis of inner surface temperature history from outer surface temperature measurement of a pipe

    International Nuclear Information System (INIS)

    Kubo, S; Ioka, S; Onchi, S; Matsumoto, Y

    2010-01-01

    When slug flow runs through a pipe, nonuniform and time-varying thermal stresses develop and there is a possibility that thermal fatigue occurs. Therefore it is necessary to know the temperature distributions and the stress distributions in the pipe for the integrity assessment of the pipe. It is, however, difficult to measure the inner surface temperature directly. Therefore establishment of the estimation method of the temperature history on inner surface of pipe is needed. As a basic study on the estimation method of the temperature history on the inner surface of a pipe with slug flow, this paper presents an estimation method of the temperature on the inner surface of a plate from the temperature on the outer surface. The relationship between the temperature history on the outer surface and the inner surface is obtained analytically. Using the results of the mathematical analysis, the inverse analysis method of the inner surface temperature history estimation from the outer surface temperature history is proposed. It is found that the inner surface temperature history can be estimated from the outer surface temperature history by applying the inverse analysis method, even when it is expressed by the multiple frequency components.

  2. Innovations in plantar pressure and foot temperature measurements in diabetes

    NARCIS (Netherlands)

    Bus, S. A.

    2016-01-01

    Plantar pressure and temperature measurements in the diabetic foot primarily contribute to identifying abnormal values that increase risk for foot ulceration, and they are becoming increasingly more integrated in clinical practice and daily life of the patient. While plantar pressure measurements

  3. Online junction temperature measurement using peak gate current

    DEFF Research Database (Denmark)

    Baker, Nick; Munk-Nielsen, Stig; Iannuzzo, Francesco

    2015-01-01

    A new method for junction temperature measurement of MOS-gated power semiconductor switches is presented. The measurement method involves detecting the peak voltage over the external gate resistor of an IGBT or MOSFET during turn-on. This voltage is directly proportional to the peak gate current...

  4. Space potential, temperature, and density profile measurements on RENTOR

    International Nuclear Information System (INIS)

    Schoch, P.M.

    1983-05-01

    Radial profiles of the space potential, electron temperature, and density have been measured on RENTOR with a heavy-ion-beam probe. The potential profile has been compared to predictions from a stochastic magnetic field fluctuation theory, using the measured temperature and density profiles. The comparison shows strong qualitative agreement in that the potential is positive and the order of T/sub e//e. There is some quantitative disagreement in that the measured radial electric fields are somewhat smaller than the theoretical predictions. To facilitate this comparison, a detailed analysis of the possible errors has been completed

  5. Temperature measuring system based on ADuC812 MCU

    International Nuclear Information System (INIS)

    Zhou Dongmei; Ge Liangquan; Cheng Feng; Li Jinfeng

    2009-01-01

    This paper introduces a temperature measuring system which is composed of a single chip microcomputer ADuC812, new type digital temperature sensor TMP100,LED display circuit and based on I 2 C bus. I 2 C bus which is invented by PHILIPS company needs only two signal lines (SDA, SCL), can realized perfect duplex synchronous data transmission. Using the method of hardware setting of device address, can completely avoid the disadvantages of device selection addressing, thus can make hardware system has simplifier and more flexible extension method. The key part of the system is composed of a single chip microcomputer ADuC812 which is compatible with MCS-51 and is invented by AD company in america. The software is compiled with 8051 assembly language. The data acquisitin single chip microcomputer measurement system with I 2 C bus fully shows the features of flexibility, precise and high integration. Proposed high accuracy measurement method to realize environment temperature measure. (authors)

  6. Proceedings of the Second Noncontact Temperature Measurement Workshop

    Science.gov (United States)

    Hale, Robert R. (Editor)

    1989-01-01

    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. Technical presentations were made concerning: NCTM needs as perceived by several NASA centers, recent ground-based NCT, research and development of industry, NASA, academia, and selected national laboratories, work-in-progress communication, and technical issues of the implementation of temperature measurement in the space environment to facilitate future U.S. materials science investigations.

  7. Measurement of rock properties at elevated pressures and temperatures

    International Nuclear Information System (INIS)

    Pincus, H.J.; Hoskins, E.R.

    1985-01-01

    The papers in this volume were presented at an ASTM symposium held on 20 June 1983 in conjunction with the 24th Annual Rock Mechanics Symposium at Texas A and M University, College Station, TX. The purpose of these papers is to present recent developments in the measurement of rock properties at elevated pressures and temperatures, and to examine and interpret the data produced by such measurement. The need for measuring rock properties at elevated pressures and temperatures has become increasingly important in recent years. Location and design of nuclear waste repositories, development of geothermal energy sites, and design and construction of deep excavations for civil, military, and mining engineering require significantly improved capabilities for measuring rock properties under conditions substantially different from those prevailing in most laboratory and in situ work. The development of high-pressure, high-temperature capabilities is also significant for the analysis of tectonic processes

  8. Neutron temperature measurements in a cryogenic hydrogenous moderator

    International Nuclear Information System (INIS)

    Ball, R.M.; Hoovler, G.S.; Lewis, R.H.

    1995-01-01

    Benchmarkings of neutronic calculations are most successful when there is a direct correlation between a measurement and an analytic result. In the thermal neutron energy region, the fluence rate as a function of moderator temperature and position within the moderator is an area of potential correlation. The measurement can be done by activating natural lutetium. The two isotopes of the element lutetium have widely different cross sections and permit the discrimination of flux shape and energy distributions at different reactor conditions. The 175 Lu has a 1/v dependence in the thermal energy region, and 176 Lu has a resonance structure that approximates a constant cross section in the same region. The saturation activation of the two isotopes has been measured in an insulated moderator container at the center of a thermal heterogeneous reactor designed for space nuclear propulsion. The measurements were made in a hydrogenous (polyethylene) moderator at three temperatures (83, 184, and 297 K) and five locations within the moderator. Simultaneously, the reactivity effect of the change in the moderator temperature was determined to be positive with an increase in temperature. The plot of activation shows the variation in neutron fluence rate and current with temperature and explains the positive reactivity coefficient. A neutron temperature can be inferred from a postulated Maxwell-Boltzmann distribution and compared with Monte Carlo or other calculations

  9. Surface temperature measurement of plasma facing components in tokamaks

    International Nuclear Information System (INIS)

    Amiel, Stephane

    2014-01-01

    During this PhD, the challenges on the non-intrusive surface temperature measurements of metallic plasma facing components in tokamaks are reported. Indeed, a precise material emissivity value is needed for classical infrared methods and the environment contribution has to be known particularly for low emissivities materials. Although methods have been developed to overcome these issues, they have been implemented solely for dedicated experiments. In any case, none of these methods are suitable for surface temperature measurement in tokamaks.The active pyrometry introduced in this study allows surface temperature measurements independently of reflected flux and emissivities using pulsed and modulated photothermal effect. This method has been validated in laboratory on metallic materials with reflected fluxes for pulsed and modulated modes. This experimental validation is coupled with a surface temperature variation induced by photothermal effect and temporal signal evolvement modelling in order to optimize both the heating source characteristics and the data acquisition and treatment. The experimental results have been used to determine the application range in temperature and detection wavelengths. In this context, the design of an active pyrometry system on tokamak has been completed, based on a bicolor camera for a thermography application in metallic (or low emissivity) environment.The active pyrometry method introduced in this study is a complementary technique of classical infrared methods used for thermography in tokamak environment which allows performing local and 2D surface temperature measurements independently of reflected fluxes and emissivities. (author) [fr

  10. Measurement of the ion temperature in a diffuse theta pinch

    International Nuclear Information System (INIS)

    Kudo, Koichi; Watanabe, Yukio; Ogi, Sukeomi; Sumikawa, Toshio; Akazaki, Masanori

    1979-01-01

    The Doppler broadening of helium ion spectra was observed, and the ion temperature of theta pinch plasma was obtained. The apparatus for the measurement consists of a spectroscope, a photomultiplier and an oscilloscope. The time variation of initial plasma density was obtained. The doppler broadening of the spectra was observed in case of the plasma density of 2 x 10 13 /cm 3 and 3 x 10 12 /cm 3 . The analyses of the spectra gave the ion temperature. The double temperature distribution was seen. The temperature of the low temperature part was 5 to 9 electron-volt, and that of the high temperature part several hundred electron-volt. The high temperature is caused by the thermalization of particles accelerated by the magnetic piston. The decay of high temperature ions is due to the charge exchange with the neutral particles. The time of the highest temperature corresponds to the time at which the luminescent layer reaches to the central axis. (Kato, T.)

  11. Measuring Systems for Thermometer Calibration in Low-Temperature Range

    Science.gov (United States)

    Szmyrka-Grzebyk, A.; Lipiński, L.; Manuszkiewicz, H.; Kowal, A.; Grykałowska, A.; Jancewicz, D.

    2011-12-01

    The national temperature standard for the low-temperature range between 13.8033 K and 273.16 K has been established in Poland at the Institute of Low Temperature and Structure Research (INTiBS). The standard consists of sealed cells for realization of six fixed points of the International Temperature Scale of 1990 (ITS-90) in the low-temperature range, an adiabatic cryostat and Isotech water and mercury triple-point baths, capsule standard resistance thermometers (CSPRT), and AC and DC bridges with standard resistors for thermometers resistance measurements. INTiBS calibrates CSPRTs at the low-temperature fixed points with uncertainties less than 1 mK. In lower temperature range—between 2.5 K and about 25 K — rhodium-iron (RhFe) resistance thermometers are calibrated by comparison with a standard which participated in the EURAMET.T-K1.1 comparison. INTiBS offers a calibration service for industrial platinum resistance thermometers and for digital thermometers between 77 K and 273 K. These types of thermometers may be calibrated at INTiBS also in a higher temperature range up to 550°C. The Laboratory of Temperature Standard at INTiBS acquired an accreditation from the Polish Centre for Accreditation. A management system according to EN ISO/IEC 17025:2005 was established at the Laboratory and presented on EURAMET QSM Forum.

  12. Measuring device for the temperature coefficient of reactor moderators

    International Nuclear Information System (INIS)

    Nakano, Yuzo.

    1987-01-01

    Purpose: To rapidly determine by automatic calculation the temperature coefficient for moderators which has been determined so far by a log of manual processings. Constitution: Each of signals from a control rod position indicator, a reactor reactivity, instrument and moderator temperature meter are inputted, and each of the signals and designed valued for the doppler temperature coefficients are stored. Recurling calculation is conducted based on the reactivity and the moderator temperature at an interval where the temperature changes of the moderators are equalized at an identical control rod position, to determine isothermic coefficient. Then, the temperature coefficient for moderator are calculated from the isothermic coefficient and the doppler temperature coefficient. The relationship between the reactivity and the moderator temperature is plotted on a X-Y recorder. The stored signals and the calculated temperature coefficient for moderators are sequentially displayed and the results are printed out when the measurement is completed. According to the present device, since the real time processing is conducted, the processing time can be shortened remarkably. Accordingly, it is possible to save the man power for the test of the nuclear reactor and improve the reactor operation performance. (Kamimura, M.)

  13. A Temperature Sensor using a Silicon-on-Insulator (SOI) Timer for Very Wide Temperature Measurement

    Science.gov (United States)

    Patterson, Richard L.; Hammoud, Ahmad; Elbuluk, Malik; Culley, Dennis E.

    2008-01-01

    A temperature sensor based on a commercial-off-the-shelf (COTS) Silicon-on-Insulator (SOI) Timer was designed for extreme temperature applications. The sensor can operate under a wide temperature range from hot jet engine compartments to cryogenic space exploration missions. For example, in Jet Engine Distributed Control Architecture, the sensor must be able to operate at temperatures exceeding 150 C. For space missions, extremely low cryogenic temperatures need to be measured. The output of the sensor, which consisted of a stream of digitized pulses whose period was proportional to the sensed temperature, can be interfaced with a controller or a computer. The data acquisition system would then give a direct readout of the temperature through the use of a look-up table, a built-in algorithm, or a mathematical model. Because of the wide range of temperature measurement and because the sensor is made of carefully selected COTS parts, this work is directly applicable to the NASA Fundamental Aeronautics/Subsonic Fixed Wing Program--Jet Engine Distributed Engine Control Task and to the NASA Electronic Parts and Packaging (NEPP) Program. In the past, a temperature sensor was designed and built using an SOI operational amplifier, and a report was issued. This work used an SOI 555 timer as its core and is completely new work.

  14. Is Oral Temperature an Accurate Measurement of Deep Body Temperature? A Systematic Review

    Science.gov (United States)

    Mazerolle, Stephanie M.; Ganio, Matthew S.; Casa, Douglas J.; Vingren, Jakob; Klau, Jennifer

    2011-01-01

    Context: Oral temperature might not be a valid method to assess core body temperature. However, many clinicians, including athletic trainers, use it rather than criterion standard methods, such as rectal thermometry. Objective: To critically evaluate original research addressing the validity of using oral temperature as a measurement of core body temperature during periods of rest and changing core temperature. Data Sources: In July 2010, we searched the electronic databases PubMed, Scopus, Cumulative Index to Nursing and Allied Health Literature (CINAHL), SPORTDiscus, Academic Search Premier, and the Cochrane Library for the following concepts: core body temperature, oral, and thermometers. Controlled vocabulary was used, when available, as well as key words and variations of those key words. The search was limited to articles focusing on temperature readings and studies involving human participants. Data Synthesis: Original research was reviewed using the Physiotherapy Evidence Database (PEDro). Sixteen studies met the inclusion criteria and subsequently were evaluated by 2 independent reviewers. All 16 were included in the review because they met the minimal PEDro score of 4 points (of 10 possible points), with all but 2 scoring 5 points. A critical review of these studies indicated a disparity between oral and criterion standard temperature methods (eg, rectal and esophageal) specifically as the temperature increased. The difference was −0.50°C ± 0.31°C at rest and −0.58°C ± 0.75°C during a nonsteady state. Conclusions: Evidence suggests that, regardless of whether the assessment is recorded at rest or during periods of changing core temperature, oral temperature is an unsuitable diagnostic tool for determining body temperature because many measures demonstrated differences greater than the predetermined validity threshold of 0.27°C (0.5°F). In addition, the differences were greatest at the highest rectal temperatures. Oral temperature cannot

  15. High-temperature ultrasonic measurements applied to directly heated samples

    International Nuclear Information System (INIS)

    Moore, R.I.; Taylor, R.E.

    1984-01-01

    High-temperature ultrasonic measurements of Young's modulus were made of graphite samples heated directly. The samples were cylindrical rods of the same geometry as that used in the multiproperty apparatus for simultaneous/consecutive measurements of a number of thermophysical properties to high temperatures. The samples were resonated in simple longitudinal vibration modes. Measurements were performed up to 2000 K. Incorporation of ultrasonic measurements of Young's modulus in the capabilities of the multiproperty apparatus is valuable because (i) ultrasonic measurements can be related to normal destructive measurements of this property; (ii) they can be used for screening materials or acceptance testing of specimens; (iii) they can be used to increase the understanding of thermophysical properties and property correlations. (author)

  16. Temperature, its measurement and control in industry - ITM '90

    International Nuclear Information System (INIS)

    Fischer, H.; Blieck, L.; Jescheck, M.; Neubert, W.; Kunze, D.

    1990-01-01

    The publication refers to the new VDE/VDI guideline 3511 and explains its practical intentions and implications by thoroughly discussing the applications of temperature sensors and their limits of use. The current state of the art in temperature measuring is fully described by the discussion of the new temperature scale introduced recently, the ITS '90. The authors of the book look in detail at the particular requirements and conditions of infrared measuring techniques using radiation thermometers as defined in DIN 5496, the applications of microprocessors (DIN-measuring-field-bus, etc.), time program emitters, and measuring transducers (EX ib, etc.). A full chapter has been devoted to the subject of surface temperature measurement. Examples referring to practical applications in industry serve as an introduction to thermal control engineering, in particular with infrared sensors, for processes such as thermal forming. New, optical thermometers for the low temperature range have been given much attention. An annex presents comprehensive tables for calculation and conversion of thermal quantities. (orig./HP) With 192 figs., 134 refs [de

  17. Gas Temperature Measurement in a Glow Discharge Plasma

    Science.gov (United States)

    Sloneker, Kenneth; Podder, Nirmol; McCurdy, William E.; Shi, Shi

    2009-10-01

    In this study a relatively inexpensive quartz protected thermocouple is used to measure the gas temperature in the positive column of a glow discharge plasma. For simplicity a K-type thermocouple is used to interpret the gas temperature from the sensor voltage at pressures from 0.5 Torr to 15 Torr and discharge currents from 5 mA to 120 mA. Gas temperature is investigated as a function of the gas pressure at fixed discharge currents and as a function of discharge current at fixed gas pressures in three different gas species (Ar, N2, and He). An infinite cylinder model is used to compute the average gas temperature of the discharge from joule heating and gas thermal conductivity. The model and measurement data agree within 1% to 10% depending on plasma parameters. Data for all three gases have a similar quasi-linear increasing error as compared to the model.

  18. Measuring Skin Temperatures with the IASI Hyperspectral Mission

    Science.gov (United States)

    Safieddine, S.; George, M.; Clarisse, L.; Clerbaux, C.

    2017-12-01

    Although the role of satellites in observing the variability of the Earth system has increased in recent decades, remote-sensing observations are still underexploited to accurately assess climate change fingerprints, in particular temperature variations. The IASI - Flux and Temperature (IASI-FT) project aims at providing new benchmarks for temperature observations using the calibrated radiances measured twice a day at any location by the IASI thermal infrared instrument on the suite of MetOp satellites (2006-2025). The main challenge is to achieve the accuracy and stability needed for climate studies, particularly that required for climate trends. Time series for land and sea skin surface temperatures are derived and compared with in situ measurements and atmospheric reanalysis. The observed trends are analyzed at seasonal and regional scales in order to disentangle natural (weather/dynamical) variability and human-induced climate forcings.

  19. High-temperature absorbed dose measurements in the megagray range

    International Nuclear Information System (INIS)

    Balian, P.; Ardonceau, J.; Zuppiroli, L.

    1988-01-01

    Organic conductors of the tetraselenotetracene family have been tested as ''high-temperature'' absorbed dose dosimeters. They were heated up to 120 0 C and irradiated at this temperature with 1-MeV electrons in order to simulate, in a short time, a much longer γ-ray irradiation. The electric resistance increase of the crystal can be considered a good measurement of the absorbed dose in the range 10 6 Gy to a few 10 8 Gy and presumably one order of magnitude more. This dosimeter also permits on-line (in-situ) measurements of the absorbed dose without removing the sensor from the irradiation site. The respective advantages of organic and inorganic dosimeters at these temperature and dose ranges are also discussed. In this connection, we outline new, but negative, results concerning the possible use of silica as a high-temperature, high-dose dosimeter. (author)

  20. Application of subsurface temperature measurements in geothermal prospecting in Iceland

    Science.gov (United States)

    Flóvenz, Ólafur G.

    1985-12-01

    In geothermal areas in Iceland aquifers are in most cases found to occur in highly permeable near-vertical fractures in the low permeability basaltic crust. Therefore heat transfer in the rocks surrounding the aquifers is mainly conductive. Temperature profiles in shallow non-flowing boreholes are used to construct a two dimensional model of the temperature distribution in the vicinity of near vertical aquifers. This is done by finite element solution of the equation of heat transfer which requires knowledge of the regional temperature gradient outside the area of geothermal activity and some constraints on the temperature within the aquifers. The model is helpful in estimating dip and location of near-vertical water bearing fractures and thus in siting production wells. An example of successful use to the method and of soil temperature measurements from a geothermal field in North-Iceland is demonstrated.

  1. Redundancy in Nigerian Business Organizations: Alternatives ...

    African Journals Online (AJOL)

    This theoretical discourse examined the incidence of work redundancy in Nigerian organizations as to offer alternative options. Certainly, some redundancy exercises may be necessary for the survival of the organizations but certain variables may influence employees' reactions to the exercises and thus influence the ...

  2. Increasing The Dexterity Of Redundant Robots

    Science.gov (United States)

    Seraji, Homayoun

    1990-01-01

    Redundant coordinates used to define additional tasks. Configuration control emerging as effective way to control motions of robot having more degrees of freedom than necessary to define trajectory of end effector and/or of object to be manipulated. Extra or redundant degrees of freedom used to give robot humanlike dexterity and versatility.

  3. Temperature measurements in thermonuclear plasmas; Mesures des temperatures dans les plasmas thermonucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Breton, D [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    The temperatures needed to produce thermonuclear reactions are of the order of several million degrees Kelvin. Devising methods for measuring such temperatures has been the subject of research in many countries. In order to present the problem clearly and to demonstrate its importance, the author reviews the various conditions which must be fulfilled in order that reactions may be qualified as thermonuclear. The relationship between the temperature and the cross-section of the reactions is studied, and it is shown that the notion of temperature in the plasmas is complex, which leads to a consideration of the temperature of the ions and that of the electrons. None of the methods for the temperature measurements is completely satisfactory because of the hypotheses which must be made, and which are seldom fulfilled during high-intensity discharges in the plasmas. In practice it is necessary to use several methods simultaneously. (author) [French] Les temperatures necessaires pour produire des reactions thermonucleaires sont de l'ordre de plusieurs millions de degres Kelvin. Les methodes envisagees pour mesurer ces temperatures font l'objet de recherches dans de nombreux pays. Afin de preciser le probleme et de montrer son importance, l'auteur rappelle les conditions qui doivent etre reunies pour que des reactions puissent etre qualifiees thermonucleaires. Il etudie la relation entre la temperature et la section efficace des reactions et montre que la notion de temperature dans les plasmas est complexe, ce qui amene a considerer la temperature des ions et celle des electrons. Aucune des methodes de mesure des temperatures n'est completement satisfaisante en raison des hypotheses qu'elles exigent et qui sont rarement realisees lors des decharges a haute intensite dans les plasmas. En pratique, il est necessaire d'utiliser plusieurs methodes simultanement. (auteur)

  4. Photonic Crystal Fiber Sensors for Strain and Temperature Measurement

    Directory of Open Access Journals (Sweden)

    Jian Ju

    2009-01-01

    Full Text Available This paper discusses the applications of photonic crystal fibers (PCFs for strain and temperature measurement. Long-period grating sensors and in-fiber modal interferometric sensors are described and compared with their conventional single-mode counterparts. The strain sensitivities of the air-silica PCF sensors are comparable or higher than those implemented in conventional single-mode fibers but the temperature sensitivities of the PCF sensors are much lower.

  5. Study of Optical Fiber Sensors for Cryogenic Temperature Measurements.

    Science.gov (United States)

    De Miguel-Soto, Veronica; Leandro, Daniel; Lopez-Aldaba, Aitor; Beato-López, Juan Jesus; Pérez-Landazábal, José Ignacio; Auguste, Jean-Louis; Jamier, Raphael; Roy, Philippe; Lopez-Amo, Manuel

    2017-11-30

    In this work, the performance of five different fiber optic sensors at cryogenic temperatures has been analyzed. A photonic crystal fiber Fabry-Pérot interferometer, two Sagnac interferometers, a commercial fiber Bragg grating (FBG), and a π-phase shifted fiber Bragg grating interrogated in a random distributed feedback fiber laser have been studied. Their sensitivities and resolutions as sensors for cryogenic temperatures have been compared regarding their advantages and disadvantages. Additionally, the results have been compared with the given by a commercial optical backscatter reflectometer that allowed for distributed temperature measurements of a single mode fiber.

  6. Containerless high temperature property measurements by atomic fluorescence

    Science.gov (United States)

    Schiffman, R. A.; Walker, C. A.

    1984-01-01

    Laser induced fluorescence (LIF) techniques for containerless study of high temperature processes and material properties was studied. Gas jet and electromagnetic levitation and electromagnetic and laser heating techniques are used with LIF in earth-based containerless high temperature experiments. Included are the development of an apparatus and its use in the studies of (1) chemical reactions on Al2O3, molybdenum, tungsten and LaB6 specimens, (2) methods for noncontact specimen temperature measurement, (3) levitation jet properties and (4) radiative lifetime and collisional energy transfer rates for electronically excited atoms.

  7. Diamond micro-Raman thermometers for accurate gate temperature measurements

    Energy Technology Data Exchange (ETDEWEB)

    Simon, Roland B.; Pomeroy, James W.; Kuball, Martin [Center for Device Thermography and Reliability, H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom)

    2014-05-26

    Determining the peak channel temperature in AlGaN/GaN high electron mobility transistors and other devices with high accuracy is an important and challenging issue. A surface-sensitive thermometric technique is demonstrated, utilizing Raman thermography and diamond microparticles to measure the gate temperature. This technique enhances peak channel temperature estimation, especially when it is applied in combination with standard micro-Raman thermography. Its application to other metal-covered areas of devices, such as field plates is demonstrated. Furthermore, this technique can be readily applied to other material/device systems.

  8. Diamond micro-Raman thermometers for accurate gate temperature measurements

    International Nuclear Information System (INIS)

    Simon, Roland B.; Pomeroy, James W.; Kuball, Martin

    2014-01-01

    Determining the peak channel temperature in AlGaN/GaN high electron mobility transistors and other devices with high accuracy is an important and challenging issue. A surface-sensitive thermometric technique is demonstrated, utilizing Raman thermography and diamond microparticles to measure the gate temperature. This technique enhances peak channel temperature estimation, especially when it is applied in combination with standard micro-Raman thermography. Its application to other metal-covered areas of devices, such as field plates is demonstrated. Furthermore, this technique can be readily applied to other material/device systems.

  9. Study of Optical Fiber Sensors for Cryogenic Temperature Measurements

    Directory of Open Access Journals (Sweden)

    Veronica De Miguel-Soto

    2017-11-01

    Full Text Available In this work, the performance of five different fiber optic sensors at cryogenic temperatures has been analyzed. A photonic crystal fiber Fabry-Pérot interferometer, two Sagnac interferometers, a commercial fiber Bragg grating (FBG, and a π-phase shifted fiber Bragg grating interrogated in a random distributed feedback fiber laser have been studied. Their sensitivities and resolutions as sensors for cryogenic temperatures have been compared regarding their advantages and disadvantages. Additionally, the results have been compared with the given by a commercial optical backscatter reflectometer that allowed for distributed temperature measurements of a single mode fiber.

  10. Temperature measurements in a wall stabilized steady flame using CARS

    KAUST Repository

    Sesha Giri, Krishna

    2017-01-05

    Flame quenching by heat loss to a surface continues to be an active area of combustion research. Close wall temperature measurements in an isothermal wall-stabilized flame are reported in this work. Conventional N-vibrational Coherent Anti-Stokes Raman Scattering (CARS) thermometry as close as 275 μm to a convex wall cooled with water has been carried out. The standard deviation of mean temperatures is observed to be ~6.5% for high temperatures (>2000K) and ~14% in the lower range (<500K). Methane/air and ethylene/air stoichiometric flames for various global strain rates based on exit bulk velocities are plotted and compared. CH* chemiluminescence is employed to determine the flame location relative to the wall. Flame locations are shown to move closer to the wall with increasing strain rates in addition to higher near-wall temperatures. Peak temperatures for ethylene are considerably higher (~250-300K) than peak temperatures for methane. Preheat zone profiles are similar for different strain rates across fuels. This work demonstrates close wall precise temperature measurments using CARS.

  11. Measuring the Surface Temperature of the Cryosphere using Remote Sensing

    Science.gov (United States)

    Hall, Dorothy K.

    2012-01-01

    A general description of the remote sensing of cryosphere surface temperatures from satellites will be provided. This will give historical information on surface-temperature measurements from space. There will also be a detailed description of measuring the surface temperature of the Greenland Ice Sheet using Moderate-Resolution Imaging Spectroradiometer (MODIS) data which will be the focus of the presentation. Enhanced melting of the Greenland Ice Sheet has been documented in recent literature along with surface-temperature increases measured using infrared satellite data since 1981. Using a recently-developed climate data record, trends in the clear-sky ice-surface temperature (IST) of the Greenland Ice Sheet have been studied using the MODIS IST product. Daily and monthly MODIS ISTs of the Greenland Ice Sheet beginning on 1 March 2000 and continuing through 31 December 2010 are now freely available to download at 6.25-km spatial resolution on a polar stereographic grid. Maps showing the maximum extent of melt for the entire ice sheet and for the six major drainage basins have been developed from the MODIS IST dataset. Twelve-year trends of the duration of the melt season on the ice sheet vary in different drainage basins with some basins melting progressively earlier over the course of the study period. Some (but not all) of the basins also show a progressively-longer duration of melt. The consistency of this IST record, with temperature and melt records from other sources will be discussed.

  12. Spatially resolved remote measurement of temperature by neutron resonance absorption

    Energy Technology Data Exchange (ETDEWEB)

    Tremsin, A.S., E-mail: ast@ssl.berkeley.edu [Space Sciences Laboratory, University of California at Berkeley, 7 Gauss Way, Berkeley, CA 94720 (United States); Kockelmann, W.; Pooley, D.E. [STFC, Rutherford Appleton Laboratory, ISIS Facility, Didcot OX11 0QX (United Kingdom); Feller, W.B. [NOVA Scientific, Inc., 10 Picker Road, Sturbridge, MA 01566 (United States)

    2015-12-11

    Deep penetration of neutrons into most engineering materials enables non-destructive studies of their bulk properties. The existence of sharp resonances in neutron absorption spectra enables isotopically-resolved imaging of elements present in a sample, as demonstrated by previous studies. At the same time the Doppler broadening of resonance peaks provides a method of remote measurement of temperature distributions within the same sample. This technique can be implemented at a pulsed neutron source with a short initial pulse allowing for the measurement of the energy of each registered neutron by the time of flight technique. A neutron counting detector with relatively high timing and spatial resolution is used to demonstrate the possibility to obtain temperature distributions across a 100 µm Ta foil with ~millimeter spatial resolution. Moreover, a neutron transmission measurement over a wide energy range can provide spatially resolved sample information such as temperature, elemental composition and microstructure properties simultaneously.

  13. Reconstructing bottom water temperatures from measurements of temperature and thermal diffusivity in marine sediments

    Science.gov (United States)

    Miesner, F.; Lechleiter, A.; Müller, C.

    2015-07-01

    Continuous monitoring of oceanic bottom water temperatures is a complicated task, even in relatively easy-to-access basins like the North or Baltic seas. Here, a method to determine annual bottom water temperature variations from inverse modeling of instantaneous measurements of temperatures and sediment thermal properties is presented. This concept is similar to climate reconstructions over several thousand years from deep borehole data. However, in contrast, the presented method aims at reconstructing the recent temperature history of the last year from sediment thermal properties and temperatures from only a few meters depth. For solving the heat equation, a commonly used forward model is introduced and analyzed: knowing the bottom water temperature variations for the preceding years and the thermal properties of the sediments, the forward model determines the sediment temperature field. The bottom water temperature variation is modeled as an annual cosine defined by the mean temperature, the amplitude and a phase shift. As the forward model operator is non-linear but low-dimensional, common inversion schemes such as the Newton algorithm can be utilized. The algorithms are tested for artificial data with different noise levels and for two measured data sets: from the North Sea and from the Davis Strait. Both algorithms used show stable and satisfying results with reconstruction errors in the same magnitude as the initial data error. In particular, the artificial data sets are reproduced with accuracy within the bounds of the artificial noise level. Furthermore, the results for the measured North Sea data show small variances and resemble the bottom water temperature variations recorded from a nearby monitoring site with relative errors smaller than 1 % in all parameters.

  14. Wireless SAW passive tag temperature measurement in the collision case

    Science.gov (United States)

    Sorokin, A.; Shepeta, A.; Wattimena, M.

    2018-04-01

    This paper describes temperature measurement in the multisensor systems based on the radio-frequency identification SAW passive tags which are currently applied in the electric power systems and the switchgears. Different approaches of temperature measurement in the collision case are shown here. The study is based on the tag model with specific topology, which allows us to determine temperature through the response signal with time-frequency information. This research considers the collision case for several passive tags as the temperature sensors which are placed in the switchgear. This research proposal is to analyze the possibility of using several SAW passive sensors in the collision case. We consider the using of the different typical elements for passive surface acoustic wave tag which applies as an anticollision passive sensor. These wireless sensors based on the surface acoustic waves tags contain specifically coded structures. This topology makes possible the reliability of increasing tag identification and the temperature measurement in the collision case. As the results for this case we illustrate simultaneous measurement of at least six sensors.

  15. Redundant arrays of IDE drives

    Energy Technology Data Exchange (ETDEWEB)

    D.A. Sanders et al.

    2002-01-02

    The authors report tests of redundant arrays of IDE disk drives for use in offline high energy physics data analysis. Parts costs of total systems using commodity EIDE disks are now at the $4000 per Terabyte level. Disk storage prices have now decreased to the point where they equal the cost per Terabyte of Storage Technology tape silos. The disks, however, offer far better granularity; even small institutions can afford to deploy systems. The tests include reports on software RAID-5 systems running under Linux 2.4 using Promise Ultra 100{trademark} disk controllers. RAID-5 protects data in case of a single disk failure by providing parity bits. Tape backup is not required. Journaling file systems are used to allow rapid recovery from crashes. The data analysis strategy is to encapsulate data and CPU processing power. Analysis for a particular part of a data set takes place on the PC where the data resides. The network is only used to put results together. They explore three methods of moving data between sites; internet transfers, not pluggable IDE disks in FireWire cases, and DVD-R disks.

  16. Redundant arrays of IDE drives

    International Nuclear Information System (INIS)

    Sanders, D.A.

    2002-01-01

    The authors report tests of redundant arrays of IDE disk drives for use in offline high energy physics data analysis. Parts costs of total systems using commodity EIDE disks are now at the $4000 per Terabyte level. Disk storage prices have now decreased to the point where they equal the cost per Terabyte of Storage Technology tape silos. The disks, however, offer far better granularity; even small institutions can afford to deploy systems. The tests include reports on software RAID-5 systems running under Linux 2.4 using Promise Ultra 100trademark disk controllers. RAID-5 protects data in case of a single disk failure by providing parity bits. Tape backup is not required. Journaling file systems are used to allow rapid recovery from crashes. The data analysis strategy is to encapsulate data and CPU processing power. Analysis for a particular part of a data set takes place on the PC where the data resides. The network is only used to put results together. They explore three methods of moving data between sites; internet transfers, not pluggable IDE disks in FireWire cases, and DVD-R disks

  17. Estimation of piping temperature fluctuations based on external strain measurements

    International Nuclear Information System (INIS)

    Morilhat, P.; Maye, J.P.

    1993-01-01

    Due to the difficulty to carry out measurements at the inner sides of nuclear reactor piping subjected to thermal transients, temperature and stress variations in the pipe walls are estimated by means of external thermocouples and strain-gauges. This inverse problem is solved by spectral analysis. Since the wall harmonic transfer function (response to a harmonic load) is known, the inner side signal will be obtained by convolution of the inverse transfer function of the system and of the strain measurement enables detection of internal temperature fluctuations in a frequency range beyond the scope of the thermocouples. (authors). 5 figs., 3 refs

  18. Low temperature measurement of the vapor pressures of planetary molecules

    Science.gov (United States)

    Kraus, George F.

    1989-01-01

    Interpretation of planetary observations and proper modeling of planetary atmospheres are critically upon accurate laboratory data for the chemical and physical properties of the constitutes of the atmospheres. It is important that these data are taken over the appropriate range of parameters such as temperature, pressure, and composition. Availability of accurate, laboratory data for vapor pressures and equilibrium constants of condensed species at low temperatures is essential for photochemical and cloud models of the atmospheres of the outer planets. In the absence of such data, modelers have no choice but to assume values based on an educated guess. In those cases where higher temperature data are available, a standard procedure is to extrapolate these points to the lower temperatures using the Clausius-Clapeyron equation. Last summer the vapor pressures of acetylene (C2H2) hydrogen cyanide (HCN), and cyanoacetylene (HC3N) was measured using two different methods. At the higher temperatures 1 torr and 10 torr capacitance manometers were used. To measure very low pressures, a technique was used which is based on the infrared absorption of thin film (TFIR). This summer the vapor pressure of acetylene was measured the TFIR method. The vapor pressure of hydrogen sulfide (H2S) was measured using capacitance manometers. Results for H2O agree with literature data over the common range of temperature. At the lower temperatures the data lie slightly below the values predicted by extrapolation of the Clausius-Clapeyron equation. Thin film infrared (TFIR) data for acetylene lie significantly below the values predicted by extrapolation. It is hoped to bridge the gap between the low end of the CM data and the upper end of the TFIR data in the future using a new spinning rotor gauge.

  19. Influence of low ambient temperature on epitympanic temperature measurement: a prospective randomized clinical study.

    Science.gov (United States)

    Strapazzon, Giacomo; Procter, Emily; Putzer, Gabriel; Avancini, Giovanni; Dal Cappello, Tomas; Überbacher, Norbert; Hofer, Georg; Rainer, Bernhard; Rammlmair, Georg; Brugger, Hermann

    2015-11-05

    Epitympanic temperature (Tty) measured with thermistor probes correlates with core body temperature (Tcore), but the reliability of measurements at low ambient temperature is unknown. The aim of this study was to determine if commercially-available thermistor-based Tty reflects Tcore in low ambient temperature and if Tty is influenced by insulation of the ear. Thirty-one participants (two females) were exposed to room (23.2 ± 0.4 °C) and low (-18.7 ± 1.0 °C) ambient temperature for 10 min using a randomized cross-over design. Tty was measured using an epitympanic probe (M1024233, GE Healthcare Finland Oy) and oesophageal temperature (Tes) with an oesophageal probe (M1024229, GE Healthcare Finland Oy) inserted into the lower third of the oesophagus. Ten participants wore ear protectors (Arton 2200, Emil Lux GmbH & Co. KG, Wermelskirchen, Switzerland) to insulate the ear from ambient air. During exposure to room temperature, mean Tty increased from 33.4 ± 1.5 to 34.2 ± 0.8 °C without insulation of the ear and from 35.0 ± 0.8 to 35.5 ± 0.7 °C with insulation. During exposure to low ambient temperature, mean Tty decreased from 32.4 ± 1.6 to 28.5 ± 2.0 °C without insulation and from 35.6 ± 0.6 to 35.2 ± 0.9 °C with insulation. The difference between Tty and Tes at low ambient temperature was reduced by 82% (from 7.2 to 1.3 °C) with insulation of the ear. Epitympanic temperature measurements are influenced by ambient temperature and deviate from Tes at room and low ambient temperature. Insulating the ear with ear protectors markedly reduced the difference between Tty and Tes and improved the stability of measurements. The use of models to correct Tty may be possible, but results should be validated in larger studies.

  20. Reliability–redundancy allocation problem considering optimal redundancy strategy using parallel genetic algorithm

    International Nuclear Information System (INIS)

    Kim, Heungseob; Kim, Pansoo

    2017-01-01

    To maximize the reliability of a system, the traditional reliability–redundancy allocation problem (RRAP) determines the component reliability and level of redundancy for each subsystem. This paper proposes an advanced RRAP that also considers the optimal redundancy strategy, either active or cold standby. In addition, new examples are presented for it. Furthermore, the exact reliability function for a cold standby redundant subsystem with an imperfect detector/switch is suggested, and is expected to replace the previous approximating model that has been used in most related studies. A parallel genetic algorithm for solving the RRAP as a mixed-integer nonlinear programming model is presented, and its performance is compared with those of previous studies by using numerical examples on three benchmark problems. - Highlights: • Optimal strategy is proposed to solve reliability redundancy allocation problem. • The redundancy strategy uses parallel genetic algorithm. • Improved reliability function for a cold standby subsystem is suggested. • Proposed redundancy strategy enhances the system reliability.

  1. Electrode for improving electrochemical measurements in high temperature water

    International Nuclear Information System (INIS)

    Sengarsai, T.

    2005-01-01

    A silver/silver-chloride (Ag/AgCl) reference electrode was specially designed and constructed in a body of oxidized titanium for potentiometric measurements under high-temperature and high-pressure conditions. To avoid the thermal decomposition of silver-chloride, the electrode is designed to maintain the reference element at low temperature while it is still connected to high-temperature process zone via a non-isothermal electrolyte bridge. This configuration leads to the development of a thermal gradient along the length of the electrode. At room temperature, the stability of the Ag/AgCl reference electrode versus a standard calomel electrode (SCE) is maintained with an accuracy of 5 mV. The electrode's performance at high temperature and pressure (up to 300 o C and 1500 psi) was examined by measuring the potential difference against platinum, which acted as a reversible hydrogen electrode (RHE). Comparison of the experimental and theoretical values verifies the reliability and reproducibility of the electrode. Deviation from the Nernst equation is considered and related to the thermal liquid junction potential (TLJP). An empirical correction factor is used to maintain the Ag/AgCl potential within an acceptable accuracy limit of ±20 mV at high temperature. (author)

  2. Real-time temperature field measurement based on acoustic tomography

    International Nuclear Information System (INIS)

    Bao, Yong; Jia, Jiabin; Polydorides, Nick

    2017-01-01

    Acoustic tomography can be used to measure the temperature field from the time-of-flight (TOF). In order to capture real-time temperature field changes and accurately yield quantitative temperature images, two improvements to the conventional acoustic tomography system are studied: simultaneous acoustic transmission and TOF collection along multiple ray paths, and an offline iteration reconstruction algorithm. During system operation, all the acoustic transceivers send modulated and filtered wideband Kasami sequences simultaneously to facilitate fast and accurate TOF measurements using cross-correlation detection. For image reconstruction, the iteration process is separated and executed offline beforehand to shorten computation time for online temperature field reconstruction. The feasibility and effectiveness of the developed methods are validated in the simulation study. The simulation results demonstrate that the proposed method can reduce the processing time per frame from 160 ms to 20 ms, while the reconstruction error remains less than 5%. Hence, the proposed method has great potential in the measurement of rapid temperature change with good temporal and spatial resolution. (paper)

  3. Temperature measurement in the liquid helium range at pressure

    International Nuclear Information System (INIS)

    Itskevich, E.S.; Krajdenov, V.F.

    1978-01-01

    The use of bronze and germanium resistance thermometers and the use of a (Au + 0.07 % Fe)-Cu thermocouple for temperature measurements from 1.5 to 4.2 K in the hydrostatic compression of up to 10 kbar are considered. To this aim, the thermometer resistance as a function of temperature and pressure is measured. It is revealed that pressure does not change the thermometric response of the bronze resistance thermometer but only shifts it to the region of lower temperatures. The identical investigations of the germanium resistance thermometer shows that strong temperature dependence and the shift of its thermometric response under the influence of pressure make the use of germanium resistance thermometers in high-pressure chambers very inconvenient. The results of the analysis of the (Au + 0.07 % Fe) - Cu thermocouple shows that with a 2 per cent accuracy the thermocouple Seebeck coefficient does not depend on pressure. It permits to use this thermocouple for temperature measurements at high pressures

  4. Constituent Ion Temperatures Measured in the Topside Ionosphere

    Science.gov (United States)

    Hsu, C. T.; Heelis, R. A.

    2017-12-01

    Plasma temperatures in the ionosphere are associated with both the dynamics and structure of the neutral and charge particles. The temperatures are determined by solar energy inputs and energy exchange between charged particles and neutrals. Previous observations show that during daytime the O+ temperature is generally higher when the fractional contribution of H+ to the plasma is high. Further simulations confirm that the daytime heat balance between the H+ and O+ always keeps the H+ at a temperature higher than the O+. In addition the plasma transport parallel and perpendicular to the magnetic field influences the plasma temperature through adiabatic heating and cooling effects. These processes are also important during the nighttime, when the source of photoionization is absent. In this work we examine a more sophisticated analysis procedure to extract individual mass dependent ion temperature and apply it on the DMSP F15 RPA measurements. The result shows that the daytime TH+ is a few hundred degrees higher than the TO+ and the nighttime temperature difference between TH+ and TO+ is indicative of mass dependent adiabatic heating and cooling processes across the equatorial region.

  5. CARS Temperature Measurements in a Combustion-Heated Supersonic Jet

    Science.gov (United States)

    Tedder, S. A.; Danehy, P. M.; Magnotti, G.; Cutler, A. D.

    2009-01-01

    Measurements were made in a combustion-heated supersonic axi-symmetric free jet from a nozzle with a diameter of 6.35 cm using dual-pump Coherent Anti-Stokes Raman Spectroscopy (CARS). The resulting mean and standard deviation temperature maps are presented. The temperature results show that the gas temperature on the centerline remains constant for approximately 5 nozzle diameters. As the heated gas mixes with the ambient air further downstream the mean temperature decreases. The standard deviation map shows evidence of the increase of turbulence in the shear layer as the jet proceeds downstream and mixes with the ambient air. The challenges of collecting data in a harsh environment are discussed along with influences to the data. The yield of the data collected is presented and possible improvements to the yield is presented are discussed.

  6. Studying Stratospheric Temperature Variation with Cosmic Ray Measurements

    Science.gov (United States)

    Zhang, Xiaohang; He, Xiaochun

    2015-04-01

    The long term stratospheric cooling in recent decades is believed to be equally important as surface warming as evidence of influences of human activities on the climate system. Un- fortunatly, there are some discrepancies among different measurements of stratospheric tem- peratures, which could be partially caused by the limitations of the measurement techniques. It has been known for decades that cosmic ray muon flux is sensitive to stratospheric temperature change. Dorman proposed that this effect could be used to probe the tempera- ture variations in the stratophere. In this talk, a method for reconstructing stratospheric temperature will be discussed. We verify this method by comparing the stratospheric tem- perature measured by radiosonde with the ones derived from cosmic ray measurement at multiple locations around the globe.

  7. Measured energy savings from using night temperature setback

    International Nuclear Information System (INIS)

    Szydlowski, R.F.; Wrench, L.E.; O'Neill, P.J.

    1993-01-01

    The measured energy savings resulting from using night temperature setback in typical light-construction wooden office buildings was determined. Researchers installed monitoring equipment in a six-building sample of two-story wooden buildings at Fort Devens, Massachusetts. Data obtained during both single-setting and night-setback operating modes were used to develop models of each building's heat consumption as a function of the difference between inside and outside temperature. These models were used to estimate seasonal savings that could be obtained from the use of night-setback thermostat control. The measured savings in heating energy from using night temperature setback for the six Fort Devens buildings ranged from 14% to 25%; the mean savings was 19.2%. Based on an energy cost of $0.65/therm of natural gas, the estimated average cost savings of using automatic setback thermostats in these buildings is $780 per year per building

  8. Temperature Measurements of Dense Plasmas by Detailed Balance

    International Nuclear Information System (INIS)

    Holl, A; Redmer, R; Ropke, G; Reinholz, H; Thiele, R; Fortmann, C; Forster, E; Cao, L; Tschentscher, T; Toleikis, S; Glenzer, S H

    2006-01-01

    Plasmas at high electron densities of n e = 10 20 - 10 26 cm -3 and moderate temperatures T e = 1 - 20 eV are important for laboratory astrophysics, high energy density science and inertial confinement fusion. These plasmas are usually referred to as Warm Dense Matter (WDM) and are characterized by a coupling parameter of Λ ∼> 1 where correlations become important. The characterization of such plasmas is still a challenging task due to the lack of direct measurement techniques for temperatures and densities. They propose to measure the Thomson scattering spectrum of vacuum-UV radiation off density fluctuations in the plasma. Collective Thomson scattering provides accurate data for the electron temperature applying first principles. Further, this method takes advantage of the spectral asymmetry resulting from detailed balance and is independent of collisional effects in these dense systems

  9. Active ion temperature measurement with heating neutral beam

    International Nuclear Information System (INIS)

    Miura, Yukitoshi; Matsuda, Toshiaki; Yamamoto, Shin

    1987-03-01

    When the heating neutral-beam (hydrogen beam) is injected into a deuterium plasma, the density of neutral particles is increased locally. By using this increased neutral particles, the local ion temperature is measured by the active charge-exchange method. The analyzer is the E//B type mass-separated neutral particle energy analyzer and the measured position is about one third outside of the plasma radius. The deuterium energy spectrum is Maxwellian, and the temperature is increased from 350 eV to 900 eV during heating. Since the local hydrogen to deuterium density concentration and the density of the heating neutral-beam as well as the ion temperature can be obtained good S/N ratio, the usefulness of this method during neutral-beam heating is confirmed by this experiment. (author)

  10. Measurements of plasma temperature and electron density in laser

    Indian Academy of Sciences (India)

    The temperature and electron density characterizing the plasma are measured by time-resolved spectroscopy of neutral atom and ion line emissions in the time window of 300–2000 ns. An echelle spectrograph coupled with a gated intensified charge coupled detector is used to record the plasma emissions.

  11. Innovative Instrumentation and Analysis of the Temperature Measurement for High Temperature Gasification

    Energy Technology Data Exchange (ETDEWEB)

    Seong W. Lee

    2006-09-30

    The project entitled, ''Innovative Instrumentation and Analysis of the Temperature Measurement for High Temperature Gasification'', was successfully completed by the Principal Investigator, Dr. S. Lee and his research team in the Center for Advanced Energy Systems and Environmental Control Technologies at Morgan State University. The major results and outcomes were presented in semi-annual progress reports and annual project review meetings/presentations. Specifically, the literature survey including the gasifier temperature measurement, the ultrasonic application in cleaning application, and spray coating process and the gasifier simulator (cold model) testing has been successfully conducted during the first year. The results show that four factors (blower voltage, ultrasonic application, injection time intervals, particle weight) were considered as significant factors that affect the temperature measurement. Then the gasifier simulator (hot model) design and the fabrication as well as the systematic tests on hot model were completed to test the significant factors on temperature measurement in the second year. The advanced Industrial analytic methods such as statistics-based experimental design, analysis of variance (ANOVA) and regression methods were applied in the hot model tests. The results show that operational parameters (i.e. air flow rate, water flow rate, fine dust particle amount, ammonia addition) presented significant impact on the temperature measurement inside the gasifier simulator. The experimental design and ANOVA are very efficient way to design and analyze the experiments. The results show that the air flow rate and fine dust particle amount are statistically significant to the temperature measurement. The regression model provided the functional relation between the temperature and these factors with substantial accuracy. In the last year of the project period, the ultrasonic and subsonic cleaning methods and coating

  12. Radon measurements with charcoal canisters temperature and humidity considerations

    Directory of Open Access Journals (Sweden)

    Živanović Miloš Z.

    2016-01-01

    Full Text Available Radon testing by using open-faced charcoal canisters is a cheap and fast screening method. Many laboratories perform the sampling and measurements according to the United States Environmental Protection Agency method - EPA 520. According to this method, no corrections for temperature are applied and corrections for humidity are based on canister mass gain. The EPA method is practiced in the Vinča Institute of Nuclear Sciences with recycled canisters. In the course of measurements, it was established that the mass gain of the recycled canisters differs from mass gain measured by Environmental Protection Agency in an active atmosphere. In order to quantify and correct these discrepancies, in the laboratory, canisters were exposed for periods of 3 and 4 days between February 2015 and December 2015. Temperature and humidity were monitored continuously and mass gain measured. No significant correlation between mass gain and temperature was found. Based on Environmental Protection Agency calibration data, functional dependence of mass gain on humidity was determined, yielding Environmental Protection Agency mass gain curves. The results of mass gain measurements of recycled canisters were plotted against these curves and a discrepancy confirmed. After correcting the independent variable in the curve equation and calculating the corrected mass gain for recycled canisters, the agreement between measured mass gain and Environmental Protection Agency mass gain curves was attained. [Projekat Ministarstva nauke Republike Srbije, br. III43009: New Technologies for Monitoring and Protection of Environment from Harmful Chemical Substances and Radiation Impact

  13. High-Temperature Thermal Diffusivity Measurements of Silicate Glasses

    Science.gov (United States)

    Pertermann, M.; Hofmeister, A. M.; Whittington, A. G.; Spera, F. J.; Zayac, J.

    2005-12-01

    Transport of heat in geologically relevant materials is of great interest because of its key role in heat transport, magmatism and volcanic activity on Earth. To better understand the thermal properties of magmatic materials at high temperatures, we measured the thermal diffusivity of four synthetic end-member silicate glasses with the following compositions: albite (NaAlSi3O8), orthoclase (KAlSi3O8), anorthite (CaAl2Si2O8), and diopside (CaMgSi2O6). Thermal diffusivity measurements were conducted with the laser-flash technique and data were acquired from room temperature to a maximum temperature near 1100°C, depending on the glass transition temperature. The presence of sub-mm sized bubbles in one of the orthoclase samples had no discernable effect on measured diffusivities. At room temperature, the three feldspar-type glasses have thermal diffusivity (D) values of 0.58-0.61 mm2/s, whereas the diopside glass has 0.52 mm2/s. With increasing temperature, D decreases by 5-10% (relative) for all samples and becomes virtually constant at intermediate temperatures. At higher temperatures, the anorthite and diopside glasses exhibit significant drops in thermal diffusivity over a 50-100°C interval, correlating with previously published heat capacity changes near the glass transition for these compositions. For anorthite, D (in mm2/s) decreases from 0.48 at 750-860°C to 0.36 at 975-1075°C; for diopside, D changes from 0.42 at 630-750°C to 0.30 at 850-910°C, corresponding to relative drops of 24 and 29%, respectively. Albite and orthoclase glasses do not exhibit this change and also lack significant changes in heat capacity near the glass transition. Instead, D is constant at 400-800°C for albite, and for orthoclase values go through a minimum at 500-600°C before increasing slightly towards 1100°C but it never exceeds the room temperature D. Our data on thermal diffusivity correlate closely with other thermophysical properties. Thus, at least in case of simple

  14. Redundant correlation effect on personalized recommendation

    Science.gov (United States)

    Qiu, Tian; Han, Teng-Yue; Zhong, Li-Xin; Zhang, Zi-Ke; Chen, Guang

    2014-02-01

    The high-order redundant correlation effect is investigated for a hybrid algorithm of heat conduction and mass diffusion (HHM), through both heat conduction biased (HCB) and mass diffusion biased (MDB) correlation redundancy elimination processes. The HCB and MDB algorithms do not introduce any additional tunable parameters, but keep the simple character of the original HHM. Based on two empirical datasets, the Netflix and MovieLens, the HCB and MDB are found to show better recommendation accuracy for both the overall objects and the cold objects than the HHM algorithm. Our work suggests that properly eliminating the high-order redundant correlations can provide a simple and effective approach to accurate recommendation.

  15. A Modular Approach to Redundant Robot Control

    International Nuclear Information System (INIS)

    Anderson, R.J.

    1997-12-01

    This paper describes a modular approach for computing redundant robot kinematics. First some conventional redundant control methods are presented and shown to be 'passive control laws', i.e. they can be represented by a network consisting of passive elements. These networks are then put into modular form by applying scattering operator techniques. Additional subnetwork modules can then be added to further shape the motion. Modules for obstacle detection, joint limit avoidance, proximity sensing, and for imposing nonlinear velocity constraints are presented. The resulting redundant robot control system is modular, flexible and robust

  16. Exploiting Redundancy in an OFDM SDR Receiver

    Directory of Open Access Journals (Sweden)

    Tomas Palenik

    2009-01-01

    Full Text Available Common OFDM system contains redundancy necessary to mitigate interblock interference and allows computationally effective single-tap frequency domain equalization in receiver. Assuming the system implements an outer error correcting code and channel state information is available in the receiver, we show that it is possible to understand the cyclic prefix insertion as a weak inner ECC encoding and exploit the introduced redundancy to slightly improve error performance of such a system. In this paper, an easy way to implement modification to an existing SDR OFDM receiver is presented. This modification enables the utilization of prefix redundancy, while preserving full compatibility with existing OFDM-based communication standards.

  17. Mutual information and redundancy in spontaneous communication between cortical neurons.

    Science.gov (United States)

    Szczepanski, J; Arnold, M; Wajnryb, E; Amigó, J M; Sanchez-Vives, M V

    2011-03-01

    An important question in neural information processing is how neurons cooperate to transmit information. To study this question, we resort to the concept of redundancy in the information transmitted by a group of neurons and, at the same time, we introduce a novel concept for measuring cooperation between pairs of neurons called relative mutual information (RMI). Specifically, we studied these two parameters for spike trains generated by neighboring neurons from the primary visual cortex in the awake, freely moving rat. The spike trains studied here were spontaneously generated in the cortical network, in the absence of visual stimulation. Under these conditions, our analysis revealed that while the value of RMI oscillated slightly around an average value, the redundancy exhibited a behavior characterized by a higher variability. We conjecture that this combination of approximately constant RMI and greater variable redundancy makes information transmission more resistant to noise disturbances. Furthermore, the redundancy values suggest that neurons can cooperate in a flexible way during information transmission. This mostly occurs via a leading neuron with higher transmission rate or, less frequently, through the information rate of the whole group being higher than the sum of the individual information rates-in other words in a synergetic manner. The proposed method applies not only to the stationary, but also to locally stationary neural signals.

  18. Water Plume Temperature Measurements by an Unmanned Aerial System (UAS

    Directory of Open Access Journals (Sweden)

    Anthony DeMario

    2017-02-01

    Full Text Available We report on the development and testing of a proof of principle water temperature measurement system deployed on an unmanned aerial system (UAS, for field measurements of thermal discharges into water. The primary elements of the system include a quad-copter UAS to which has been integrated, for the first time, both a thermal imaging infrared (IR camera and an immersible probe that can be dipped below the water surface to obtain vertical water temperature profiles. The IR camera is used to take images of the overall water surface to geo-locate the plume, while the immersible probe provides quantitative temperature depth profiles at specific locations. The full system has been tested including the navigation of the UAS, its ability to safely carry the sensor payload, and the performance of both the IR camera and the temperature probe. Finally, the UAS sensor system was successfully deployed in a pilot field study at a coal burning power plant, and obtained images and temperature profiles of the thermal effluent.

  19. Water Plume Temperature Measurements by an Unmanned Aerial System (UAS).

    Science.gov (United States)

    DeMario, Anthony; Lopez, Pete; Plewka, Eli; Wix, Ryan; Xia, Hai; Zamora, Emily; Gessler, Dan; Yalin, Azer P

    2017-02-07

    We report on the development and testing of a proof of principle water temperature measurement system deployed on an unmanned aerial system (UAS), for field measurements of thermal discharges into water. The primary elements of the system include a quad-copter UAS to which has been integrated, for the first time, both a thermal imaging infrared (IR) camera and an immersible probe that can be dipped below the water surface to obtain vertical water temperature profiles. The IR camera is used to take images of the overall water surface to geo-locate the plume, while the immersible probe provides quantitative temperature depth profiles at specific locations. The full system has been tested including the navigation of the UAS, its ability to safely carry the sensor payload, and the performance of both the IR camera and the temperature probe. Finally, the UAS sensor system was successfully deployed in a pilot field study at a coal burning power plant, and obtained images and temperature profiles of the thermal effluent.

  20. Cluster temperature. Methods for its measurement and stabilization

    International Nuclear Information System (INIS)

    Makarov, G N

    2008-01-01

    Cluster temperature is an important material parameter essential to many physical and chemical processes involving clusters and cluster beams. Because of the diverse methods by which clusters can be produced, excited, and stabilized, and also because of the widely ranging values of atomic and molecular binding energies (approximately from 10 -5 to 10 eV) and numerous energy relaxation channels in clusters, cluster temperature (internal energy) ranges from 10 -3 to about 10 8 K. This paper reviews research on cluster temperature and describes methods for its measurement and stabilization. The role of cluster temperature in and its influence on physical and chemical processes is discussed. Results on the temperature dependence of cluster properties are presented. The way in which cluster temperature relates to cluster structure and to atomic and molecular interaction potentials in clusters is addressed. Methods for strong excitation of clusters and channels for their energy relaxation are discussed. Some applications of clusters and cluster beams are considered. (reviews of topical problems)

  1. Constant-Temperature Calorimetry for In-Core Power Measurement

    International Nuclear Information System (INIS)

    Radcliff, Thomas D.; Miller, Don W.; Kauffman, Andrew C.

    2000-01-01

    Reactor thermal limits are based on fuel energy deposition and cladding temperature. This paper presents a two-wire in-core instrument that directly measures fuel energy deposition. The instrument is based on the addition of heat through resistive dissipation of input electrical energy to a small mass of reactor fuel or fuel analogue. A feedback loop controls the input electrical energy needed to maintain the fuel mass at a nearly constant temperature regardless of the nuclear energy deposited in the mass. Energy addition to the fuel and fuel temperature feedback to the controller are provided by a resistive heating element embedded in the fuel mass. As long as the external heat transfer environment remains constant, the input electrical energy is inversely related to the actual nuclear energy deposition. To demonstrate this instrument, we first scaled the sensor and controller parameters and then used the results to guide fabrication of prototype instruments. In-reactor testing was performed to measure the instrument sensitivity, linearity, bandwidth, and long-term drift characteristics of the prototypes. The instrument is shown to be capable of high-sensitivity, linear measurement of fuel energy deposition with sufficient bandwidth for safety-related measurements. It is also clear that a means to compensate the sensor for changes in the external heat transfer environment is required. Means of actively measuring heat losses and performing this compensation are discussed

  2. Redundancy in electronic health record corpora: analysis, impact on text mining performance and mitigation strategies.

    Science.gov (United States)

    Cohen, Raphael; Elhadad, Michael; Elhadad, Noémie

    2013-01-16

    The increasing availability of Electronic Health Record (EHR) data and specifically free-text patient notes presents opportunities for phenotype extraction. Text-mining methods in particular can help disease modeling by mapping named-entities mentions to terminologies and clustering semantically related terms. EHR corpora, however, exhibit specific statistical and linguistic characteristics when compared with corpora in the biomedical literature domain. We focus on copy-and-paste redundancy: clinicians typically copy and paste information from previous notes when documenting a current patient encounter. Thus, within a longitudinal patient record, one expects to observe heavy redundancy. In this paper, we ask three research questions: (i) How can redundancy be quantified in large-scale text corpora? (ii) Conventional wisdom is that larger corpora yield better results in text mining. But how does the observed EHR redundancy affect text mining? Does such redundancy introduce a bias that distorts learned models? Or does the redundancy introduce benefits by highlighting stable and important subsets of the corpus? (iii) How can one mitigate the impact of redundancy on text mining? We analyze a large-scale EHR corpus and quantify redundancy both in terms of word and semantic concept repetition. We observe redundancy levels of about 30% and non-standard distribution of both words and concepts. We measure the impact of redundancy on two standard text-mining applications: collocation identification and topic modeling. We compare the results of these methods on synthetic data with controlled levels of redundancy and observe significant performance variation. Finally, we compare two mitigation strategies to avoid redundancy-induced bias: (i) a baseline strategy, keeping only the last note for each patient in the corpus; (ii) removing redundant notes with an efficient fingerprinting-based algorithm. (a)For text mining, preprocessing the EHR corpus with fingerprinting yields

  3. Temperature measurement of RE123 bulk superconductors on magnetizing process

    International Nuclear Information System (INIS)

    Yokoyama, K.; Kaneyama, M.; Oka, T.; Fujishiro, H.; Noto, K.

    2004-01-01

    We study on the magnetization behavior of to magnetize RE123 bulk superconductors to apply it as strong magnets. Through magnetizing process, the temperature of bulk superconductors is raised by pinning loss caused by the magnetic fluxes motion (e.g. flux jump of flux flow), and the trapped field is decreased. This paper presents the measurement of temperature changes of Sm123 bulk superconductors during the exciting process by iteratively magnetizing pulsed-field operation with reducing amplitudes (IMRA) method. Five thermocouples are put on the surface of Sm123 bulk superconductor of 46 mm in diameter. The temperatures at the center, on the growth sector boundary (GSB) line and in the sector region surrounded by GSB's line (inter-GSB region) are monitored. The temperature at a cold stage is also measured. A Hall sensor is attached near the center thermocouple to measure the trapped field. After a bulk superconductor is cooled by the GM type refrigerator until 40 K, iterative pulsed-fields of 2.32-5.42 T are applied by a magnetizing coil. When high magnetic field of 5.42 T is applied, a temperature of bulk superconductor reaches to 72.4 K and the magnetic field distribution has C form with which a part of circle is dented, and then, a trapped field is 2.28 T. When a lower magnetic field of 4.64 T is applied, a maximum temperature is 68.3 K and a trapped field is raised to 2.70 T, and moreover, the distribution becomes round shape like field-cooling method (FC). We showed clearly that heat generation by pinning loss was related to the mechanism of magnetic field capture

  4. Microwave measurements of water vapor partial pressure at high temperatures

    International Nuclear Information System (INIS)

    Latorre, V.R.

    1991-01-01

    One of the desired parameters in the Yucca Mountain Project is the capillary pressure of the rock comprising the repository. This parameter is related to the partial pressure of water vapor in the air when in equilibrium with the rock mass. Although there are a number of devices that will measure the relative humidity (directly related to the water vapor partial pressure), they generally will fail at temperatures on the order of 150C. Since thee author has observed borehole temperatures considerably in excess of this value in G-Tunnel at the Nevada Test Site (NTS), a different scheme is required to obtain the desired partial pressure data at higher temperatures. This chapter presents a microwave technique that has been developed to measure water vapor partial pressure in boreholes at temperatures up to 250C. The heart of the system is a microwave coaxial resonator whose resonant frequency is inversely proportional to the square root of the real part of the complex dielectric constant of the medium (air) filling the resonator. The real part of the dielectric constant of air is approximately equal to the square of the refractive index which, in turn, is proportional to the partial pressure of the water vapor in the air. Thus, a microwave resonant cavity can be used to measure changes in the relative humidity or partial pressure of water vapor in the air. Since this type of device is constructed of metal, it is able to withstand very high temperatures. The actual limitation is the temperature limit of the dielectric material in the cable connecting the resonator to its driving and monitoring equipment-an automatic network analyzer in our case. In the following sections, the theory of operation, design, construction, calibration and installation of the microwave diagnostics system is presented. The results and conclusions are also presented, along with suggestions for future work

  5. Attachment of Free Filament Thermocouples for Temperature Measurements on CMC

    Science.gov (United States)

    Lei, Jih-Fen; Cuy, Michael D.; Wnuk, Stephen P.

    1997-01-01

    Ceramic Matrix Composites (CMC) are being developed for use as enabling materials for advanced aeropropulsion engine and high speed civil transport applications. The characterization and testing of these advanced materials in hostile, high-temperature environments require accurate measurement of the material temperatures. Commonly used wire Thermo-Couples (TC) can not be attached to this ceramic based material via conventional spot-welding techniques. Attachment of wire TC's with commercially available ceramic cements fail to provide sufficient adhesion at high temperatures. While advanced thin film TC technology provides minimally intrusive surface temperature measurement and has good adhesion on the CMC, its fabrication requires sophisticated and expensive facilities and is very time consuming. In addition, the durability of lead wire attachments to both thin film TC's and the substrate materials requires further improvement. This paper presents a newly developed attachment technique for installation of free filament wire TC's with a unique convoluted design on ceramic based materials such as CMC's. Three CMC's (SiC/SiC CMC and alumina/alumina CMC) instrumented with type IC, R or S wire TC's were tested in a Mach 0.3 burner rig. The CMC temperatures measured from these wire TC's were compared to that from the facility pyrometer and thin film TC's. There was no sign of TC delamination even after several hours exposure to 1200 C. The test results proved that this new technique can successfully attach wire TC's on CMC's and provide temperature data in hostile environments. The sensor fabrication process is less expensive and requires very little time compared to that of the thin film TC's. The same installation technique/process can also be applied to attach lead wires for thin film sensor systems.

  6. Thermal conductivity measurements at cryogenic temperatures at LASA

    International Nuclear Information System (INIS)

    Broggi, F.; Pedrini, D.; Rossi, L.

    1995-08-01

    Here the improvement realised to have better control of the reference junction temperature and measurements carried out on Nb 3 Sn cut out from 2 different coils (named LASA3 and LASA5), showing the difference between the longitudinal and the transverse thermal conductivity, is described. Two different methods of data analysis are presented, the DAM (derivative approximated method) and the TCI (thermal conductivity integral. The data analysis for the tungsten and the LASA5 coil has been done according to the two methods showing that the TCI method with polynomial functions is not adequate to describe the thermal conductivity. Only a polynomial fit based on the TCI method but limited at a lower order than the nominal, when the data are well distributed along the range of measurements, can describe reasonably the thermal conductivity dependence with the temperature. Finally the measurements on a rod of BSCCO 2212 high T c superconductor are presented

  7. Effect of In-situ Cure on Measurement of Glass Transition Temperatures in High-temperature Thermosetting Polymers

    Science.gov (United States)

    2015-01-01

    TEMPERATURES IN HIGH-TEMPERATURE THERMOSETTING POLYMERS 5a. CONTRACT NUMBER In-House 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S...illustrated the difficulties inherent in measurement of the glass transition temperature of this high-temperature thermosetting polymer via dynamic...copyright protection in the United States. EFFECT OF IN-SITU CURE ON MEASUREMENT OF GLASS TRANSITION TEMPERATURES IN HIGH-TEMPERATURE THERMOSETTING

  8. Temperature measurement in WTE boilers using suction pyrometers.

    Science.gov (United States)

    Rinaldi, Fabio; Najafi, Behzad

    2013-11-15

    The temperature of the flue-gas in the post combustion zone of a waste to energy (WTE) plant has to be maintained within a fairly narrow range of values, the minimum of which is prescribed by the European Waste Directive 2000/76/CE, whereas the maximum value must be such as to ensure the preservation of the materials and the energy efficiency of the plant. A high degree of accuracy in measuring and controlling the aforementioned temperature is therefore required. In almost the totality of WTE plants this measurement process is carried out by using practical industrial thermometers, such as bare thermocouples and infrared radiation (IR) pyrometers, even if affected by different physical contributions which can make the gas temperature measurements incorrect. The objective of this paper is to analyze errors and uncertainties that can arise when using a bare thermocouple or an IR pyrometer in a WTE plant and to provide a method for the in situ calibration of these industrial sensors through the use of suction pyrometers. The paper describes principle of operation, design, and uncertainty contributions of suction pyrometers, it also provides the best estimation of the flue-gas temperature in the post combustion zone of a WTE plant and the estimation of its expanded uncertainty.

  9. Electro optical system to measure strains at high temperature

    Science.gov (United States)

    Sciammarella, Cesar A.

    1991-12-01

    The measurement of strains at temperatures of the order of 1000 C has become a very important field of research. Technological advances in areas such as the analysis of high speed aircraft structures and high efficiency thermal engines require operational temperatures of this order of magnitude. Current techniques for the measurement of strains, such as electrical strain gages, are at the limit of their useful range and new methods need to be developed. Optical techniques are very attractive in this type of application because of their noncontacting nature. Holography is of particular interest because a minimal preparation of the surfaces is required. Optoelectronics holography is specially suited for this type of application, from the point of view of industrial use. There are a number of technical problems that need to be overcome to measure strains using holographic interferometry at high temperatures. Some of these problems are discussed, and solutions are given. A specimen instrumented with high temperature strains gages is used to compare the results of both technologies.

  10. Temperature Measurement in WTE Boilers Using Suction Pyrometers

    Directory of Open Access Journals (Sweden)

    Fabio Rinaldi

    2013-11-01

    Full Text Available The temperature of the flue-gas in the post combustion zone of a waste to energy (WTE plant has to be maintained within a fairly narrow range of values, the minimum of which is prescribed by the European Waste Directive 2000/76/CE, whereas the maximum value must be such as to ensure the preservation of the materials and the energy efficiency of the plant. A high degree of accuracy in measuring and controlling the aforementioned temperature is therefore required. In almost the totality of WTE plants this measurement process is carried out by using practical industrial thermometers, such as bare thermocouples and infrared radiation (IR pyrometers, even if affected by different physical contributions which can make the gas temperature measurements incorrect. The objective of this paper is to analyze errors and uncertainties that can arise when using a bare thermocouple or an IR pyrometer in a WTE plant and to provide a method for the in situ calibration of these industrial sensors through the use of suction pyrometers. The paper describes principle of operation, design, and uncertainty contributions of suction pyrometers, it also provides the best estimation of the flue-gas temperature in the post combustion zone of a WTE plant and the estimation of its expanded uncertainty.

  11. The measurement of plasma temperature by height scattering

    International Nuclear Information System (INIS)

    Katzenstein, J.

    1976-04-01

    One of the most accurate methods for the determination of the electron and ion temperature of a plasma is the measurement of the spectrum of the light scattered from a monoshromatic laser beam by the plasma electrons. The simple case of uncorrelated electrons is treated in detail showing the scattered spectrum to be a simple Gaussian whose half-breadth is proportional to the mean electron thermal velocity hence the square root of electron temperature. The results of a more general treatment are also reviewed which takes into account electron-ion correlations. Experimental requirements on the laser, the spetral instrumentation, and the data analysis are discussed. (author)

  12. Electron temperature measurement of tungsten inert gas arcs

    International Nuclear Information System (INIS)

    Tanaka, Manabu; Tashiro, Shinichi

    2008-01-01

    In order to make clear the physical grounds of deviations from LTE (Local Thermodynamic Equilibrium) in the atmospheric helium TIG arcs electron temperature and LTE temperature obtained from electron number density were measured by using of line-profile analysis of the laser scattering method without an assumption of LTE. The experimental results showed that in comparison with the argon TIG arcs, the region where a deviation from LTE occurs tends to expand in higher arc current because the plasma reaches the similar state to LTE within shorter distance from the cathode due to the slower cathode jet velocity

  13. Measurements of hot water service consumptions: temperature influence

    Energy Technology Data Exchange (ETDEWEB)

    Secchi, R.; Vallat, D.; Cyssau, R. (COSTIC, Saint Remy-les-Chevreuse (France))

    This article presents a campaign of measurements of which the aim is the observation of consumptions, for individual installations equiped with a hot water tank. The study takes an interest in the temperature of the water in the tank and the instantaneous power of the generator. The instrumentation, the installations and the results of this campaign are presented in this paper. The conclusion is the ''economic'' temperature of hot sanitary water is below 60/sup 0/C but above 55/sup 0/C.

  14. Determining noncondensible gas fractions at elevated temperatures and pressures using wet and dry bulb temperature measurements

    International Nuclear Information System (INIS)

    Griffith, P.; Bowman, J.

    1987-01-01

    The work reported in this note was undertaken to provide a method of determining the noncondensible gas fractions in a steam-gas mixture such as might be found in large reactor safety experiment like LOFT. In essence, the method used involves measuring the wet and dry bulb temperatures and using an algorithm, in place of the psychometric chart, to determine the partial pressure of the noncondensible gas in the mixture. In accomplishing this, the authors did the following: (1) extended the use of wet and dry-bulb temperature readings to determine mixture composition up to a temperature of 589 K and a pressure of 4.13 x 10 6 Pa. (2) developed an algorithm to reduce the data (3) found which materials would survive those temperatures

  15. Mars Exospheric Temperature Trends as Revealed by MAVEN NGIMS Measurements

    Science.gov (United States)

    Bougher, Stephen W.; Olsen, Kirk; Roeten, Kali; Bell, Jared; Mahaffy, Paul; Benna, Mehdi; Elrod, Meredith; Jakosky, Bruce

    2015-11-01

    The Martian dayside upper thermosphere and exosphere temperatures (Texo) have been the subject of considerable debate and study since the first Mariner ultraviolet spectrometer (UVS) measurements (1969-1972), up to recent Mars Express SPICAM UVS measurements (2004-present) (e.g., see reviews by Stewart 1987; Bougher et al. 2000, 2014; Müeller-Wodarg et al. 2008; Stiepen et al. 2014). Prior to MAVEN, the Martian upper atmosphere thermal structure was poorly constrained by a limited number of both in-situ and remote sensing measurements at selected locations, seasons, and periods scattered throughout the solar cycle. Nevertheless, it is recognized that the Mars orbit eccentricity determines that both the solar cycle and seasonal variations in upper atmosphere temperatures must be considered together. The MAVEN NGIMS instrument measures the neutral composition of the major gas species (e.g. He, N, O, CO, N2, O2, NO, Ar and CO2) and their major isotopes, with a vertical resolution of ~5 km for targeted species and a target accuracy of <25% for most of these species (Mahaffy et al. 2014; 2015). Corresponding temperatures can now be derived from the neutral scale heights (especially CO2, Ar, and N2) (e.g. Mahaffy et al. 2015; Bougher et al. 2015). Texo mean temperatures spanning ~200 to 300 km are examined for both Deep Dip and Science orbits over 11-February 2015 (Ls ~ 290) to 14-July 2015 (Ls ~ 12). During these times, dayside sampling below 300 km occurred from the dusk terminator, across the dayside, and approaching the dawn terminator. NGIMS temperatures are investigated to extract spatial (e.g. SZA) and temporal (e.g. orbit-to-orbit, seasonal, solar rotational) variability and trends over this sampling period. Solar and seasonal driven trends in Texo are clearly visible, but orbit-to-orbit variability is significant, and demands further investigation to uncover the major drivers that are responsible.

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

    Energy Technology Data Exchange (ETDEWEB)

    Seong W. Lee

    2003-09-01

    During this reporting period, the literature survey including the gasifier temperature measurement literature, the ultrasonic application and its background study in cleaning application, and spray coating process are completed. The gasifier simulator (cold model) testing has been successfully conducted. Four factors (blower voltage, ultrasonic application, injection time intervals, particle weight) were considered as significant factors that affect the temperature measurement. The Analysis of Variance (ANOVA) was applied to analyze the test data. The analysis shows that all four factors are significant to the temperature measurements in the gasifier simulator (cold model). The regression analysis for the case with the normalized room temperature shows that linear model fits the temperature data with 82% accuracy (18% error). The regression analysis for the case without the normalized room temperature shows 72.5% accuracy (27.5% error). The nonlinear regression analysis indicates a better fit than that of the linear regression. The nonlinear regression model's accuracy is 88.7% (11.3% error) for normalized room temperature case, which is better than the linear regression analysis. The hot model thermocouple sleeve design and fabrication are completed. The gasifier simulator (hot model) design and the fabrication are completed. The system tests of the gasifier simulator (hot model) have been conducted and some modifications have been made. Based on the system tests and results analysis, the gasifier simulator (hot model) has met the proposed design requirement and the ready for system test. The ultrasonic cleaning method is under evaluation and will be further studied for the gasifier simulator (hot model) application. The progress of this project has been on schedule.

  17. Image Registration Using Redundant Wavelet Transforms

    National Research Council Canada - National Science Library

    Brown, Richard

    2001-01-01

    .... In our research, we present a fundamentally new wavelet-based registration algorithm utilizing redundant transforms and a masking process to suppress the adverse effects of noise and improve processing efficiency...

  18. Use of aluminum nitride to obtain temperature measurements in a high temperature and high radiation environment

    Science.gov (United States)

    Wernsman, Bernard R.; Blasi, Raymond J.; Tittman, Bernhard R.; Parks, David A.

    2016-04-26

    An aluminum nitride piezoelectric ultrasonic transducer successfully operates at temperatures of up to 1000.degree. C. and fast (>1 MeV) neutron fluencies of more than 10.sup.18 n/cm.sup.2. The transducer comprises a transparent, nitrogen rich aluminum nitride (AlN) crystal wafer that is coupled to an aluminum cylinder for pulse-echo measurements. The transducer has the capability to measure in situ gamma heating within the core of a nuclear reactor.

  19. The Effects of Race Conditions When Implementing Single-Source Redundant Clock Trees in Triple Modular Redundant Synchronous Architectures

    Science.gov (United States)

    Berg, Melanie D.; Kim, Hak S.; Phan, Anthony M.; Seidleck, Christina M.; Label, Kenneth A.; Pellish, Jonathan A.; Campola, Michael J.

    2016-01-01

    We present the challenges that arise when using redundant clock domains due to their time-skew. Radiation data show that a singular clock domain provides an improved triple modular redundant (TMR) scheme over redundant clocks.

  20. Calibrating the HISA temperature: Measuring the temperature of the Riegel-Crutcher cloud

    Science.gov (United States)

    Dénes, H.; McClure-Griffiths, N. M.; Dickey, J. M.; Dawson, J. R.; Murray, C. E.

    2018-06-01

    H I self absorption (HISA) clouds are clumps of cold neutral hydrogen (H I) visible in front of warm background gas, which makes them ideal places to study the properties of the cold atomic component of the interstellar medium (ISM). The Riegel-Crutcher (R-C) cloud is the most striking HISA feature in the Galaxy. It is one of the closest HISA clouds to us and is located in the direction of the Galactic Centre, which provides a bright background. High-resolution interferometric measurements have revealed the filamentary structure of this cloud, however it is difficult to accurately determine the temperature and the density of the gas without optical depth measurements. In this paper we present new H I absorption observations with the Australia Telescope Compact Array (ATCA) against 46 continuum sources behind the Riegel-Crutcher cloud to directly measure the optical depth of the cloud. We decompose the complex H I absorption spectra into Gaussian components using an automated machine learning algorithm. We find 300 Gaussian components, from which 67 are associated with the R-C cloud (0 temperature and find it to be between 20 and 80 K. Our measurements uncover a temperature gradient across the cloud with spin temperatures decreasing towards positive Galactic latitudes. We also find three new OH absorption lines associated with the cloud, which support the presence of molecular gas.

  1. Redundancy for electric motors in spacecraft applications

    Science.gov (United States)

    Smith, Robert J.; Flew, Alastair R.

    1986-01-01

    The parts of electric motors which should be duplicated in order to provide maximum reliability in spacecraft application are identified. Various common types of redundancy are described. The advantages and disadvantages of each are noted. The principal types are illustrated by reference to specific examples. For each example, constructional details, basic performance data and failure modes are described, together with a discussion of the suitability of particular redundancy techniques to motor types.

  2. Dynamic Control of Kinematically Redundant Robotic Manipulators

    Directory of Open Access Journals (Sweden)

    Erling Lunde

    1987-07-01

    Full Text Available Several methods for task space control of kinematically redundant manipulators have been proposed in the literature. Most of these methods are based on a kinematic analysis of the manipulator. In this paper we propose a control algorithm in which we are especially concerned with the manipulator dynamics. The algorithm is particularly well suited for the class of redundant manipulators consisting of a relatively small manipulator mounted on a larger positioning part.

  3. MICROWAVE NOISE MEASUREMENT OF ELECTRON TEMPERATURES IN AFTERGLOW PLASMAS

    Energy Technology Data Exchange (ETDEWEB)

    Leiby, Jr., C. C.; McBee, W. D.

    1963-10-15

    Transient electron temperatures in afterglow plasmas were determined for He (5 and 10 torr), Ne, and Ne plus or minus 5% Ar (2.4 and 24 torr) by combining measurements of plasma microwave noise power, and plasma reflectivity and absorptivity. Use of a low-noise parametric preamplifier permitted continuous detection during the afterglow of noise power at 5.5 Bc in a 1 Mc bandwidth. Electron temperature decays were a function of pressure and gas but were slower than predicted by electron energy loss mechanisms. The addition of argon altered the electron density decay in the neon afterglow but the electron temperature decay was not appreciably changed. Resonances in detected noise power vs time in the afterglow were observed for two of the three plasma waveguide geometries studied. These resonances correlate with observed resonances in absorptivity and occur over the same range of electron densities for a given geometry independent of gas type and pressure. (auth)

  4. NELIOTA: First temperature measurement of lunar impact flashes

    Science.gov (United States)

    Bonanos, A. Z.; Avdellidou, C.; Liakos, A.; Xilouris, E. M.; Dapergolas, A.; Koschny, D.; Bellas-Velidis, I.; Boumis, P.; Charmandaris, V.; Fytsilis, A.; Maroussis, A.

    2018-04-01

    We report the first scientific results from the NELIOTA (NEO Lunar Impacts and Optical TrAnsients) project, which has recently begun lunar monitoring observations with the 1.2-m Kryoneri telescope. NELIOTA aims to detect faint impact flashes produced by near-Earth meteoroids and asteroids and thereby help constrain the size-frequency distribution of near-Earth objects in the decimeter to meter range. The NELIOTA setup, consisting of two fast-frame cameras observing simultaneously in the R and I bands, enables - for the first time - direct analytical calculation of the flash temperatures. We present the first ten flashes detected, for which we find temperatures in the range 1600 to 3100 K, in agreement with theoretical values. Two of these flashes were detected on multiple frames in both filters and therefore yield the first measurements of the temperature drop for lunar flashes. In addition, we compute the impactor masses, which range between 100 g and 50 kg.

  5. Standard guide for high-temperature static strain measurement

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1998-01-01

    1.1 This guide covers the selection and application of strain gages for the measurement of static strain up to and including the temperature range from 425 to 650°C (800 to 1200°F). This guide reflects some current state-of-the-art techniques in high temperature strain measurement, and will be expanded and updated as new technology develops. 1.2 This practice assumes that the user is familiar with the use of bonded strain gages and associated signal conditioning and instrumentation as discussed in Refs. (1) and (2). The strain measuring systems described are those that have proven effective in the temperature range of interest and were available at the time of issue of this practice. It is not the intent of this practice to limit the user to one of the gage types described nor is it the intent to specify the type of system to be used for a specific application. However, in using any strain measuring system including those described, the proposer must be able to demonstrate the capability of the proposed sy...

  6. Methods of Temperature and Emission Measure Determination of Coronal Loops

    Science.gov (United States)

    Cirtain, J. W.; Schmelz, J. T.; Martens, P. C. H.

    2002-05-01

    Recent observational results from both SOHO-EIT and TRACE indicate that coronal loops are isothermal along their length (axially). These results are obtained from a narrowband filter ratio method that assumes that the plasma is isothermal along the line of sight (radially). However, these temperatures vary greatly from those derived from differential emission measure (DEM) curves produced from spectral lines recorded by SOHO-CDS. The DEM results indicate that the loops are neither axially nor radially isothermal. This discrepancy was investigated by Schmelz et al. (2001). They chose pairs of iron lines from the same CDS data set to mimic the EIT and TRACE loop results. Ratios of different lines gave different temperatures, indicating that the plasma was not radially isothermal. In addition the results indicated that the loop was axially isothermal, even though the DEM analysis of the same data showed this result to be false. Here we have analyzed the EIT data for the CDS loop published by Schmelz et al. (2001). We took the ratios of the 171-to-195 and 195-to-284 filter data, and made temperature maps of the loop. The results indicate that the loop is axially isothermal, but different temperatures were found for each pair of filters. Both ratio techniques force the resultant temperature to lie within the range where the response functions (for filters) or the emissivity functions (for lines) overlap; isothermal loops are therefore a byproduct of the analysis. This conclusion strengthens support for the idea that temperature and emission measure results from filter ratio methods may be misleading or even drastically wrong. This research was funded in part by the NASA/TRACE MODA grant for Montana State University. Solar physics research at the University of Memphis is supported by NASA grant NAG5-9783.

  7. Fabry-Perot measurements of barium temperature in fluorescent lamps

    International Nuclear Information System (INIS)

    Hadrath, S; Garner, R

    2010-01-01

    A scanning Fabry-Perot interferometer (FPI) is used to determine the temperature of barium atoms that are liberated from the electrodes of fluorescent lamps during their steady-state operation. Barium, a constituent of the work function lowering emitter material that is placed on the tungsten coil that forms the electrode, is liberated primarily by evaporation from the hot (∼1300 K) thermionic electrode. However, there may be situations or modes of operation in which barium is, in addition, sputtered, a condition which may lead to increased end-darkening, shortened life and increased mercury consumption in the lamp. Using the FPI diagnostic, the occurrence of sputtering is inferred when barium temperatures are much greater than the electrode temperature. The FPI diagnostic senses resonance radiation (λ = 553 nm) emitted by barium atoms excited in the low pressure discharge environment, and infers temperature from the Doppler broadened linewidth. The diagnostic has proven to be successful in a number of situations. Measurements have been made on rare gas discharges and on Hg-argon discharges for different discharge currents, gas pressures and auxiliary coil currents. Measurements are phase resolved for ac-driven discharges.

  8. Measured Performance of a Low Temperature Air Source Heat Pump

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, R. K. [Johnson Research LLC, Pueblo West, CO (United States)

    2013-09-01

    A 4-ton Low Temperature Heat Pump (LTHP) manufactured by Hallowell International was installed in a residence near New Haven, Connecticut and monitored over two winters of operation. After attending to some significant service issues, the heat pump operated as designed. This report should be considered a review of the dual compressor 'boosted heat pump' technology. The Low Temperature Heat Pumpsystem operates with four increasing levels of capacity (heat output) as the outdoor temperature drops. The system was shown to select capacity correctly, supplying the appropriate amount of heat to the house across the full range of outdoor temperatures. The system's Coefficient of Performance (Seasonal COP, or SCOP) over two entire winters was calculated, based on measured data, to be 3.29over the first winter and 2.68 over the second winter. A second seasonal efficiency calculation by a different method yielded a SCOP of 2.78 for the first winter and 2.83 for the second winter. This second seasonal efficiency calculation was determined by comparing measured heat pump energy use to the in situ energy use with resistance heat alone. This method is the ratio of the slopes of thedaily energy use load lines.

  9. Temperature measurement on neurological pulse generators during MR scans

    Directory of Open Access Journals (Sweden)

    Alesch François

    2002-09-01

    Full Text Available Abstract According to manufacturers of both magnetic resonance imaging (MRI machines, and implantable neurological pulse generators (IPGs, MRI is contraindicated for patients with IPGs. A major argument for this restriction is the risk to induce heat in the leads due to the electromagnetic field, which could be dangerous for the surrounding brain parenchyma. The temperature change on the surface of the case of an ITREL-III (Medtronic Inc., Minneapolis, MN and the lead tip during MRI was determined. An anatomical realistic and a cubic phantom, filled with phantom material mimicking human tissue, and a typical lead configuration were used to imitate a patient who carries an IPG for deep brain stimulation. The measurements were performed in a 1.5 T and a 3.0 T MRI. 2.1°C temperature increases at the lead tip uncovered the lead tip as the most critical part concerning heating problems in IPGs. Temperature increases in other locations were low compared to the one at the lead tip. The measured temperature increase of 2.1°C can not be considered as harmful to the patient. Comparison with the results of other studies revealed the avoidance of loops as a practical method to reduce heating during MRI procedures.

  10. Temperature measurement and control system for transtibial prostheses: Functional evaluation.

    Science.gov (United States)

    Ghoseiri, Kamiar; Zheng, Yong Ping; Leung, Aaron K L; Rahgozar, Mehdi; Aminian, Gholamreza; Lee, Tat Hing; Safari, Mohammad Reza

    2018-01-01

    The accumulation of heat inside the prosthetic socket increases skin temperature and fosters perspiration, which consequently leads to high tissue stress, friction blister, discomfort, unpleasant odor, and decreased prosthesis suspension and use. In the present study, the prototype of a temperature measurement and control (TM&C) system was designed, fabricated, and functionally evaluated in a phantom model of the transtibial prosthetic socket. The TM&C system was comprised of 12 thermistors divided equally into two groups that arranged internal and external to a prosthetic silicone liner. Its control system was programmed to select the required heating or cooling function of a thermal pump to provide thermal equilibrium based on the amount of temperature difference from a defined set temperature, or the amount of difference between the mean temperature recorded by inside and outside thermistors. A thin layer of aluminum was used for thermal conduction between the thermal pump and different sites around the silicone liner. The results showed functionality of the TM&C system for thermoregulation inside the prosthetic socket. However, enhancing the structure of this TM&C system, increasing its thermal power, and decreasing its weight and cost are main priorities before further development.

  11. Recovery Temperature, Transition, and Heat Transfer Measurements at Mach 5

    Science.gov (United States)

    Brinich, Paul F.

    1961-01-01

    Schlieren, recovery temperature, and heat-transfer measurements were made on a hollow cylinder and a cone with axes alined parallel to the stream. Both the cone and cylinder were equipped with various bluntnesses, and the tests covered a Reynolds number range up to 20 x 10(exp 6) at a free-stream Mach number of 4.95 and wall to free-stream temperature ratios from 1.8 to 5.2 (adiabatic). A substantial transition delay due to bluntness was found for both the cylinder and the cone. For the present tests (Mach 4.95), transition was delayed by a factor of 3 on the cylinder and about 2 on the cone, these delays being somewhat larger than those observed in earlier tests at Mach 3.1. Heat-transfer tests on the cylinder showed only slight effects of wall temperature level on transition location; this is to be contrasted to the large transition delays observed on conical-type bodies at low surface temperatures at Mach 3.1. The schlieren and the peak-recovery-temperature methods of detecting transition were compared with the heat-transfer results. The comparison showed that the first two methods identified a transition point which occurred just beyond the end of the laminar run as seen in the heat-transfer data.

  12. How Redundant Are Redundant Color Adjectives? An Efficiency-Based Analysis of Color Overspecification

    OpenAIRE

    Rubio-Fern?ndez, Paula

    2016-01-01

    Color adjectives tend to be used redundantly in referential communication. I propose that redundant color adjectives are often intended to exploit a color contrast in the visual context and hence facilitate object identification, despite not being necessary to establish unique reference. Two language-production experiments investigated two types of factors that may affect the use of redundant color adjectives: factors related to the efficiency of color in the visual context and factors relate...

  13. Measurement of Laser Weld Temperatures for 3D Model Input

    Energy Technology Data Exchange (ETDEWEB)

    Dagel, Daryl [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Grossetete, Grant [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Maccallum, Danny O. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-10-01

    Laser welding is a key joining process used extensively in the manufacture and assembly of critical components for several weapons systems. Sandia National Laboratories advances the understanding of the laser welding process through coupled experimentation and modeling. This report summarizes the experimental portion of the research program, which focused on measuring temperatures and thermal history of laser welds on steel plates. To increase confidence in measurement accuracy, researchers utilized multiple complementary techniques to acquire temperatures during laser welding. This data serves as input to and validation of 3D laser welding models aimed at predicting microstructure and the formation of defects and their impact on weld-joint reliability, a crucial step in rapid prototyping of weapons components.

  14. Gas temperature measurements in short duration turbomachinery test facilities

    Science.gov (United States)

    Cattafesta, L. N.; Epstein, A. H.

    1988-07-01

    Thermocouple rakes for use in short-duration turbomachinery test facilities have been developed using very fine thermocouples. Geometry variations were parametrically tested and showed that bare quartz junction supports (76 microns in diameter) yielded superior performance, and were rugged enough to survive considerable impact damage. Using very low cost signal conditioning electronics, temperature accuracies of 0.3 percent were realized yielding turbine efficiency measurements at the 1-percent level. Ongoing work to improve this accuracy is described.

  15. PCPV instrumentation and measurement techniques at elevated temperatures

    International Nuclear Information System (INIS)

    Zemann, H.

    1978-11-01

    Strain measurement within the structural concrete of the prototype Prestressed Concrete Pressure Vessel have been performed during a one year operation at elevated temperatures up to 120 0 C. Laboratory investigations on the properties of the gauges and the concrete mix are applied to separate the different contributions to the strain data. A decrease of creep and loss of prestress and the arise of stable conditions is observed. (author)

  16. Estimating Wet Bulb Globe Temperature Using Standard Meteorological Measurements

    International Nuclear Information System (INIS)

    Hunter, C.H.

    1999-01-01

    The heat stress management program at the Department of Energy''s Savannah River Site (SRS) requires implementation of protective controls on outdoor work based on observed values of wet bulb globe temperature (WBGT). To ensure continued compliance with heat stress program requirements, a computer algorithm was developed which calculates an estimate of WBGT using standard meteorological measurements. In addition, scripts were developed to generate a calculation every 15 minutes and post the results to an Intranet web site

  17. EPR-based distance measurements at ambient temperature

    Science.gov (United States)

    Krumkacheva, Olesya; Bagryanskaya, Elena

    2017-07-01

    Pulsed dipolar (PD) EPR spectroscopy is a powerful technique allowing for distance measurements between spin labels in the range of 2.5-10.0 nm. It was proposed more than 30 years ago, and nowadays is widely used in biophysics and materials science. Until recently, PD EPR experiments were limited to cryogenic temperatures (T biomolecules, the influence of a linker between the spin probe and biomolecule, and future opportunities.

  18. In situ measurement of the junction temperature of light emitting diodes using a flexible micro temperature sensor.

    Science.gov (United States)

    Lee, Chi-Yuan; Su, Ay; Liu, Yin-Chieh; Fan, Wei-Yuan; Hsieh, Wei-Jung

    2009-01-01

    This investigation aimed to fabricate a flexible micro resistive temperature sensor to measure the junction temperature of a light emitting diode (LED). The junction temperature is typically measured using a thermal resistance measurement approach. This approach is limited in that no standard regulates the timing of data capture. This work presents a micro temperature sensor that can measure temperature stably and continuously, and has the advantages of being lightweight and able to monitor junction temperatures in real time. Micro-electro-mechanical-systems (MEMS) technologies are employed to minimize the size of a temperature sensor that is constructed on a stainless steel foil substrate (SS-304 with 30 μm thickness). A flexible micro resistive temperature sensor can be fixed between the LED chip and the frame. The junction temperature of the LED can be measured from the linear relationship between the temperature and the resistance. The sensitivity of the micro temperature sensor is 0.059 ± 0.004 Ω/°C. The temperature of the commercial CREE(®) EZ1000 chip is 119.97 °C when it is thermally stable, as measured using the micro temperature sensor; however, it was 126.9 °C, when measured by thermal resistance measurement. The micro temperature sensor can be used to replace thermal resistance measurement and performs reliably.

  19. In Situ Measurement of the Junction Temperature of Light Emitting Diodes Using a Flexible Micro Temperature Sensor

    Directory of Open Access Journals (Sweden)

    Wei-Jung Hsieh

    2009-06-01

    Full Text Available This investigation aimed to fabricate a flexible micro resistive temperature sensor to measure the junction temperature of a light emitting diode (LED. The junction temperature is typically measured using a thermal resistance measurement approach. This approach is limited in that no standard regulates the timing of data capture. This work presents a micro temperature sensor that can measure temperature stably and continuously, and has the advantages of being lightweight and able to monitor junction temperatures in real time. Micro-electro-mechanical-systems (MEMS technologies are employed to minimize the size of a temperature sensor that is constructed on a stainless steel foil substrate (SS-304 with 30 μm thickness. A flexible micro resistive temperature sensor can be fixed between the LED chip and the frame. The junction temperature of the LED can be measured from the linear relationship between the temperature and the resistance. The sensitivity of the micro temperature sensor is 0.059 ± 0.004 Ω/°C. The temperature of the commercial CREE® EZ1000 chip is 119.97 °C when it is thermally stable, as measured using the micro temperature sensor; however, it was 126.9 °C, when measured by thermal resistance measurement. The micro temperature sensor can be used to replace thermal resistance measurement and performs reliably.

  20. MTF measurement of IR optics in different temperature ranges

    Science.gov (United States)

    Bai, Alexander; Duncker, Hannes; Dumitrescu, Eugen

    2017-10-01

    Infrared (IR) optical systems are at the core of many military, civilian and manufacturing applications and perform mission critical functions. To reliably fulfill the demanding requirements imposed on today's high performance IR optics, highly accurate, reproducible and fast lens testing is of crucial importance. Testing the optical performance within different temperature ranges becomes key in many military applications. Due to highly complex IR-Applications in the fields of aerospace, military and automotive industries, MTF Measurement under realistic environmental conditions become more and more relevant. A Modulation Transfer Function (MTF) test bench with an integrated thermal chamber allows measuring several sample sizes in a temperature range from -40 °C to +120°C. To reach reliable measurement results under these difficult conditions, a specially developed temperature stable design including an insulating vacuum are used. The main function of this instrument is the measurement of the MTF both on- and off-axis at up to +/-70° field angle, as well as measurement of effective focal length, flange focal length and distortion. The vertical configuration of the system guarantees a small overall footprint. By integrating a high-resolution IR camera with focal plane array (FPA) in the detection unit, time consuming measurement procedures such as scanning slit with liquid nitrogen cooled detectors can be avoided. The specified absolute accuracy of +/- 3% MTF is validated using internationally traceable reference optics. Together with a complete and intuitive software solution, this makes the instrument a turn-key device for today's state-of- the-art optical testing.

  1. High-temperature rate constant measurements for OH+xylenes

    KAUST Repository

    Elwardani, Ahmed Elsaid

    2015-06-01

    The overall rate constants for the reactions of hydroxyl (OH) radicals with o-xylene (k 1), m-xylene (k 2), and p-xylene (k 3) were measured behind reflected shock waves over 890-1406K at pressures of 1.3-1.8atm using OH laser absorption near 306.7nm. Measurements were performed under pseudo-first-order conditions. The measured rate constants, inferred using a mechanism-fitting approach, can be expressed in Arrhenius form as:k1=2.93×1013exp(-1350.3/T)cm3mol-1s-1(890-1406K)k2=3.49×1013exp(-1449.3/T)cm3mol-1s-1(906-1391K)k3=3.5×1013exp(-1407.5/T)cm3mol-1s-1(908-1383K)This paper presents, to our knowledge, first high-temperature measurements of the rate constants of the reactions of xylene isomers with OH radicals. Low-temperature rate-constant measurements by Nicovich et al. (1981) were combined with the measurements in this study to obtain the following Arrhenius expressions, which are applicable over a wider temperature range:k1=2.64×1013exp(-1181.5/T)cm3mol-1s-1(508-1406K)k2=3.05×109exp(-400/T)cm3mol-1s-1(508-1391K)k3=3.0×109exp(-440/T)cm3mol-1s-1(526-1383K) © 2015 The Combustion Institute.

  2. Active silicon x-ray for measuring electron temperature

    International Nuclear Information System (INIS)

    Snider, R.T.

    1994-07-01

    Silicon diodes are commonly used for x-ray measurements in the soft x-ray region between a few hundred ev and 20 keV. Recent work by Cho has shown that the charge collecting region in an underbiased silicon detector is the depletion depth plus some contribution from a region near the depleted region due to charge-diffusion. The depletion depth can be fully characterized as a function of the applied bias voltage and is roughly proportional to the squart root of the bias voltage. We propose a technique to exploit this effect to use the silicon within the detector as an actively controlled x-ray filter. With reasonable silicon manufacturing methods, a silicon diode detector can be constructed in which the sensitivity of the collected charge to the impinging photon energy spectrum can be changed dynamically in the visible to above the 20 keV range. This type of detector could be used to measure the electron temperature in, for example, a tokamak plasma by sweeping the applied bias voltage during a plasma discharge. The detector samples different parts of the energy spectrum during the bias sweep, and the data collected contains enough information to determine the electron temperature. Benefits and limitations of this technique will be discussed along with comparisons to similar methods for measuring electron temperature and other applications of an active silicon x-ray filter

  3. Measuring the temperature history of isochorically heated warm dense metals

    Science.gov (United States)

    McGuffey, Chris; Kim, J.; Park, J.; Moody, J.; Emig, J.; Heeter, B.; Dozieres, M.; Beg, Fn; McLean, Hs

    2017-10-01

    A pump-probe platform has been designed for soft X-ray absorption spectroscopy near edge structure measurements in isochorically heated Al or Cu samples with temperature of 10s to 100s of eV. The method is compatible with dual picosecond-class laser systems and may be used to measure the temperature of the sample heated directly by the pump laser or by a laser-driven proton beam Knowledge of the temperature history of warm dense samples will aid equation of state measurements. First, various low- to mid-Z targets were evaluated for their suitability as continuum X-ray backlighters over the range 200-1800 eV using a 10 J picosecond-class laser with relativistic peak intensity Alloys were found to be more suitable than single-element backlighters. Second, the heated sample package was designed with consideration of target thickness and tamp layers using atomic physics codes. The results of the first demonstration attempts will be presented. This work was supported by the U.S. DOE under Contract No. DE-SC0014600.

  4. Laser metrology in fluid mechanics granulometry, temperature and concentration measurements

    CERN Document Server

    Boutier, Alain

    2013-01-01

    In fluid mechanics, non-intrusive measurements are fundamental in order to improve knowledge of the behavior and main physical phenomena of flows in order to further validate codes.The principles and characteristics of the different techniques available in laser metrology are described in detail in this book.Velocity, temperature and concentration measurements by spectroscopic techniques based on light scattered by molecules are achieved by different techniques: laser-induced fluorescence, coherent anti-Stokes Raman scattering using lasers and parametric sources, and absorption sp

  5. Measurement of ocean temperature and salinity via microwave radiometry

    Science.gov (United States)

    Blume, H.-J. C.; Kendall, B. M.; Fedors, J. C.

    1978-01-01

    Sea-surface temperature with an accuracy of 1 C and salinity with an accuracy of 1% were measured with a 1.43 and 2.65 GHz radiometer system after correcting for the influence of cosmic radiation, intervening atmosphere, sea-surface roughness, and antenna beamwidth. The radiometers are a third-generation system using null-balancing and feedback noise injection. Flight measurements from aircraft over bay regions and coastal areas of the Atlantic resulted in contour maps with spatial resolution of 0.5 km.

  6. Electron temperature measurements in lowdensity plasmas by helium spectroscopy

    International Nuclear Information System (INIS)

    Brenning, N.

    1977-09-01

    This method to use relative intensities of singlet and triplet lines of neutral helium to measure electron temperature in low-density plasmas is examined. Calculations from measured and theoretical data about transitions in neutral helium are carried out and compared to experimental results. It is found that relative intensities of singlet and triplet lines from neutral helium only can be used for TE determination in low-density, short-duration plasmas. The most important limiting processes are excitation from the metastable 2 3 S level and excitation transfer in collisions between electrons and excited helium atoms. An evaluation method is suggested, which minimizes the effect of these processes. (author)

  7. Void fraction measurement system for high temperature flows

    Energy Technology Data Exchange (ETDEWEB)

    Teyssedou, A; Aube, F; Champagne, P [Montreal Univ., PQ (Canada). Institut de Genie Energetique

    1992-05-01

    A {gamma}-ray absorption technique has been developed for measuring the axial distribution of the void fraction for high-temperature and high-pressure two-phase flows. The system is mounted on a moving platform driven by a high-power stepping motor. A personal computer (IBM AT) connected to a data acquisition system is used to control the displacement of the {gamma} source and detector, and to read the response of the detector. All the measurement procedures are carried out automatically by dedicated software developed for this purpose. (Author).

  8. Individualized estimation of human core body temperature using noninvasive measurements.

    Science.gov (United States)

    Laxminarayan, Srinivas; Rakesh, Vineet; Oyama, Tatsuya; Kazman, Josh B; Yanovich, Ran; Ketko, Itay; Epstein, Yoram; Morrison, Shawnda; Reifman, Jaques

    2018-06-01

    A rising core body temperature (T c ) during strenuous physical activity is a leading indicator of heat-injury risk. Hence, a system that can estimate T c in real time and provide early warning of an impending temperature rise may enable proactive interventions to reduce the risk of heat injuries. However, real-time field assessment of T c requires impractical invasive technologies. To address this problem, we developed a mathematical model that describes the relationships between T c and noninvasive measurements of an individual's physical activity, heart rate, and skin temperature, and two environmental variables (ambient temperature and relative humidity). A Kalman filter adapts the model parameters to each individual and provides real-time personalized T c estimates. Using data from three distinct studies, comprising 166 subjects who performed treadmill and cycle ergometer tasks under different experimental conditions, we assessed model performance via the root mean squared error (RMSE). The individualized model yielded an overall average RMSE of 0.33 (SD = 0.18)°C, allowing us to reach the same conclusions in each study as those obtained using the T c measurements. Furthermore, for 22 unique subjects whose T c exceeded 38.5°C, a potential lower T c limit of clinical relevance, the average RMSE decreased to 0.25 (SD = 0.20)°C. Importantly, these results remained robust in the presence of simulated real-world operational conditions, yielding no more than 16% worse RMSEs when measurements were missing (40%) or laden with added noise. Hence, the individualized model provides a practical means to develop an early warning system for reducing heat-injury risk. NEW & NOTEWORTHY A model that uses an individual's noninvasive measurements and environmental variables can continually "learn" the individual's heat-stress response by automatically adapting the model parameters on the fly to provide real-time individualized core body temperature estimates. This

  9. A Cause-Consequence Chart of a Redundant Protection System

    DEFF Research Database (Denmark)

    Nielsen, Dan Sandvik; Platz, O.; Runge, B.

    1975-01-01

    A cause-consequence chart is applied in analysing failures of a redundant protection system (a core spray system in a nuclear power plant). It is shown how the diagram provides a basis for calculating two probability measures for malfunctioning of the protection system. The test policy of compone...... of components is taken into account. The possibility of using parameter variation as a basis for the choice of test policy is indicated.......A cause-consequence chart is applied in analysing failures of a redundant protection system (a core spray system in a nuclear power plant). It is shown how the diagram provides a basis for calculating two probability measures for malfunctioning of the protection system. The test policy...

  10. submitter Experimental temperature measurements for the energy amplifier test

    CERN Document Server

    Calero, J; Gallego, E; Gálvez, J; García Tabares, L; González, E; Jaren, J; López, C; Lorente, A; Martínez Val, J M; Oropesa, J; Rubbia, C; Rubio, J A; Saldana, F; Tamarit, J; Vieira, S

    1996-01-01

    A uranium thermometer has been designed and built in order to make local power measurements in the First Energy Amplifier Test (FEAT). Due to the experimental conditions power measurements of tens to hundreds of nW were required, implying a sensitivity in the temperature change measurements of the order of 1 mK. A uranium thermometer accurate enough to match that sensitivity has been built. The thermometer is able to determine the absolute energetic gain obtained in a tiny subcritical uranium assembly exposed to a proton beam of kinetic energies between 600 MeV and 2.75 GeV. In addition, the thermometer measurements have provided information about the spatial power distribution and the shape of the neutron spallation cascade.

  11. Incident detection and isolation in drilling using analytical redundancy relations

    DEFF Research Database (Denmark)

    Willersrud, Anders; Blanke, Mogens; Imsland, Lars

    2015-01-01

    must be avoided. This paper employs model-based diagnosis using analytical redundancy relations to obtain residuals which are affected differently by the different incidents. Residuals are found to be non-Gaussian - they follow a multivariate t-distribution - hence, a dedicated generalized likelihood...... measurements available. In the latter case, isolation capability is shown to be reduced to group-wise isolation, but the method would still detect all serious events with the prescribed false alarm probability...

  12. Temperature measurement in French atomic piles; La mesure des temperatures dans les piles atomiques francaises

    Energy Technology Data Exchange (ETDEWEB)

    Weill, J; Rastoix, G

    1950-10-01

    In the Chatillon reactor the temperature is measured (1) in the interior of one of the vertical A1 cylinders filled with UO{sub 2} (temperature interval 20 to 70 deg. C), and (2) in the center of the tank containing D{sub 2}O (20 to 50 deg. C). The instruments used are silver-constantan thermocouples; the wires are insulated by SiO{sub 2} sheaths, those immersed in D{sub 2}O being placed within Al cases 10 mm diameter. In the Saclay reactor the temperature is taken (1) in the interior of 4 U rods (20 to 300 deg. C), (2) at 2 points of the D{sub 2}O mass (20 to 60 deg. C), (3) at one point in graphite (20 to 100 deg. C), and (4) at 5 points in the catalytic setup (200 deg. C). Copper-constantan couples are used (Ag-constantan is not suitable above 150 deg. C); the wires are enclosed in a sheath of glass fabric. In both reactors the accuracy of the temperature measurements is 0.5 deg. C. (author)

  13. Insulated skin temperature as a measure of core body temperature for individuals wearing CBRN protective clothing

    International Nuclear Information System (INIS)

    Richmond, V L; Wilkinson, D M; Blacker, S D; Horner, F E; Carter, J; Rayson, M P; Havenith, G

    2013-01-01

    This study assessed the validity of insulated skin temperature (T is ) to predict rectal temperature (T re ) for use as a non-invasive measurement of thermal strain to reduce the risk of heat illness for emergency service personnel. Volunteers from the Police, Fire and Rescue, and Ambulance Services performed role-related tasks in hot (30 °C) and neutral (18 °C) conditions, wearing service specific personal protective equipment. Insulated skin temperature and micro climate temperature (T mc ) predicted T re with an adjusted r 2 = 0.87 and standard error of the estimate (SEE) of 0.19 °C. A bootstrap validation of the equation resulted in an adjusted r 2 = 0.85 and SEE = 0.20 °C. Taking into account the 0.20 °C error, the prediction of T re resulted in a sensitivity and specificity of 100% and 91%, respectively. Insulated skin temperature and T mc can be used in a model to predict T re in emergency service personnel wearing CBRN protective clothing with an SEE of 0.2 °C. However, the model is only valid for T is over 36.5 °C, above which thermal stability is reached between the core and the skin. (paper)

  14. Measuring artificial recharge with fiber optic distributed temperature sensing.

    Science.gov (United States)

    Becker, Matthew W; Bauer, Brian; Hutchinson, Adam

    2013-01-01

    Heat was used as a tracer to measure infiltration rates from a recharge basin. The propagation of diurnal oscillation of surface water temperature into the basin bed was monitored along a transect using Fiber Optic Distributed Temperature Sensing (FODTS). The propagation rate was related to downward specific discharge using standard theory of heat advection and dispersion in saturated porous media. An estimate of the temporal variation of heat propagation was achieved using a wavelet transform to find the phase lag between the surface temperature diurnal oscillation and the correlated oscillation at 0.33 and 0.98 m below the bed surface. The wavelet results compared well to a constant velocity model of thermal advection and dispersion during periods of relatively constant discharge rates. The apparent dispersion of heat was found to be due primarily to hydrodynamic mechanisms rather than thermal diffusion. Specific discharge estimates using the FODTS technique also compared well to water balance estimates over a four month period, although there were occasional deviations that have yet to be adequately explained. The FODTS technique is superior to water balance in that it produces estimates of infiltration rate every meter along the cable transect, every half hour. These high resolution measurements highlighted areas of low infiltration and demonstrated the degradation of basin efficiency due to source waters of high suspended solids. FODTS monitoring promises to be a useful tool for diagnosing basin performance in an era of increasing groundwater demand. © 2012, The Author(s). Groundwater © 2012, National Ground Water Association.

  15. Registered Report: Measuring Unconscious Deception Detection by Skin Temperature

    Directory of Open Access Journals (Sweden)

    Anna Elisabeth Van 't Veer

    2014-05-01

    Full Text Available Findings from the deception detection literature suggest that although people are not skilled in consciously detecting a liar, they may intuit that something about the person telling a lie is off. In the current proposal, we argue that observing a liar influences the observer’s physiology even though the observer may not be consciously aware of being lied to (i.e., the observers’ direct deception judgment does not accurately differentiate between liars and truth-tellers. To test this hypothesis, participants’ finger temperature will be measured while they watch videos of persons who are either honest or dishonest about their identity. We hypothesize that skin temperature will be lower when observing a liar than when observing a truth-teller. Additionally, we test whether perceiving a liar influences finger skin temperature differently when an individual is, or is not, alerted to the possibility of deceit. We do this by varying participants’ awareness of the fact that they might be lied to. Next to measuring physiological responses to liars and truth-tellers, self-reported direct and indirect veracity judgments (i.e., trustworthiness and liking of the target persons will be assessed. We hypothesize that indirect veracity judgments will better distinguish between liars and truth-tellers than direct veracity judgments.

  16. Intuitive theories of information: beliefs about the value of redundancy.

    Science.gov (United States)

    Soll, J B

    1999-03-01

    In many situations, quantity estimates from multiple experts or diagnostic instruments must be collected and combined. Normatively, and all else equal, one should value information sources that are nonredundant, in the sense that correlation in forecast errors should be minimized. Past research on the preference for redundancy has been inconclusive. While some studies have suggested that people correctly place higher value on uncorrelated inputs when collecting estimates, others have shown that people either ignore correlation or, in some cases, even prefer it. The present experiments show that the preference for redundancy depends on one's intuitive theory of information. The most common intuitive theory identified is the Error Tradeoff Model (ETM), which explicitly distinguishes between measurement error and bias. According to ETM, measurement error can only be averaged out by consulting the same source multiple times (normatively false), and bias can only be averaged out by consulting different sources (normatively true). As a result, ETM leads people to prefer redundant estimates when the ratio of measurement error to bias is relatively high. Other participants favored different theories. Some adopted the normative model, while others were reluctant to mathematically average estimates from different sources in any circumstance. In a post hoc analysis, science majors were more likely than others to subscribe to the normative model. While tentative, this result lends insight into how intuitive theories might develop and also has potential ramifications for how statistical concepts such as correlation might best be learned and internalized. Copyright 1999 Academic Press.

  17. Temperature dependent measurement of internal damping of austenitic stainless steels

    Directory of Open Access Journals (Sweden)

    Oravcová Monika

    2018-01-01

    Full Text Available This article is aimed on the analysis of the internal damping changes of austenitic stainless steels AISI 304, AISI 316L and AISI 316Ti depending from temperature. In experimental measurements only resonance method was used which is based on continuous excitation of oscillations of the specimens and the whole apparatus vibrates at the frequency near to the resonance. Microplastic processes and dissipation of energy within the metals are evaluated and investigated by internal damping measurements. Damping capacity of materials is closely tied to the presence of defects including second phase particles and voids. By measuring the energy dissipation in the material, we can determine the elastic characteristics, Youngs modulus, the level of stress relaxation and many other.

  18. Embedded DAQ System Design for Temperature and Humidity Measurement

    Directory of Open Access Journals (Sweden)

    Tarique Rafique Memon

    2016-05-01

    Full Text Available In this work, we have proposed a cost effective DAQ (Data Acquisition system design useful for local industries by using user friendly LABVIEW (Laboratory Virtual Instrumentation Electronic Workbench. The proposed system can measure and control different industrial parameters which can be presented in graphical icon format. The system design is proposed for 8-channels, whereas tested and recorded for two parameters i.e. temperature and RH (Relative Humidity. Both parameters are set as per upper and lower limits and controlled using relays. Embedded system is developed using standard microcontroller to acquire and process the analog data and plug-in for further processing using serial interface with PC using LABVIEW. The designed system is capable of monitoring and recording the corresponding linkage between temperature and humidity in industrial unit's and indicates the abnormalities within the process and control those abnormalities through relays

  19. Zircaloy sheathed thermocouples for PWR fuel rod temperature measurements

    International Nuclear Information System (INIS)

    Anderson, J.V.; Wesley, R.D.; Wilkins, S.C.

    1979-01-01

    Small diameter zircaloy sheathed thermocouples have been developed by EG and G Idaho, Inc., at the Idaho National Engineering Laboratory. Surface mounted thermocouples were developed to measure the temperature of zircaloy clad fuel rods used in the Thermal Fuels Behavior Program (TFBP), and embedded thermocouples were developed for use by the Loss-of-Fluid Test (LOFT) Program for support tests using zircaloy clad electrically heated nuclear fuel rod simulators. The first objective of this developmental effort was to produce zircaloy sheathed thermocouples to replace titanium sheathed thermocouples and thereby eliminate the long-term corrosion of the titanium-to-zircaloy attachment weld. The second objective was to reduce the sheath diameter to obtain faster thermal response and minimize cladding temperature disturbance due to thermocouple attachment

  20. EPR-based distance measurements at ambient temperature.

    Science.gov (United States)

    Krumkacheva, Olesya; Bagryanskaya, Elena

    2017-07-01

    Pulsed dipolar (PD) EPR spectroscopy is a powerful technique allowing for distance measurements between spin labels in the range of 2.5-10.0nm. It was proposed more than 30years ago, and nowadays is widely used in biophysics and materials science. Until recently, PD EPR experiments were limited to cryogenic temperatures (TEPR as well as other approaches based on EPR (e.g., relaxation enhancement; RE). In this paper, we review the features of PD EPR and RE at ambient temperatures, in particular, requirements on electron spin phase memory time, ways of immobilization of biomolecules, the influence of a linker between the spin probe and biomolecule, and future opportunities. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. The Measurement and Interpretation of Transformation Temperatures in Nitinol

    Science.gov (United States)

    Duerig, T. W.; Pelton, A. R.; Bhattacharya, K.

    2017-12-01

    A previous paper (Duerig and Bhattacharya in Shap Mem Superelasticity 1:153-161, 2015) introduced several engineering considerations surrounding the R-phase in Nitinol and highlighted a common, if not pervasive, misconception regarding the use of the term Af by the medical device industry. This paper brings additional data to bear on the issue and proposes more accurate terminology. Moreover, a variety of tools are used to establish the forward and reverse stress-temperature phase diagrams for a superelastic wire typical of that used in medical devices. Once established, the two most common methods of measuring transformation temperatures, Differential Scanning Calorimetry and Bend Free Recovery, are tested against the observed behavior. Light is also shed upon the origin of the Clausius-Clapeyron ratio (d σ/d T), the triple point, and why such large variations are reported in superelastic alloys.

  2. Embedded DAQ System Design for Temperature and Humidity Measurement

    International Nuclear Information System (INIS)

    Memon, T.R.

    2013-01-01

    In this work, we have proposed a cost effective DAQ (Data Acquisition) system design useful for local industries by using user friendly LABVIEW (Laboratory Virtual Instrumentation Electronic Workbench). The proposed system can measure and control different industrial parameters which can be presented in graphical icon format. The system design is proposed for 8-channels, whereas tested and recorded for two parameters i.e. temperature and RH (Relative Humidity). Both parameters are set as per upper and lower limits and controlled using relays. Embedded system is developed using standard microcontroller to acquire and process the analog data and plug-in for further processing using serial interface with PC using LABVIEW. The designed system is capable of monitoring and recording the corresponding linkage between temperature and humidity in industrial unit's and indicates the abnormalities within the process and control those abnormalities through relays. (author)

  3. Measurement of a surface heat flux and temperature

    Science.gov (United States)

    Davis, R. M.; Antoine, G. J.; Diller, T. E.; Wicks, A. L.

    1994-04-01

    The Heat Flux Microsensor is a new sensor which was recently patented by Virginia Tech and is just starting to be marketed by Vatell Corp. The sensor is made using the thin-film microfabrication techniques directly on the material that is to be measured. It consists of several thin-film layers forming a differential thermopile across a thermal resistance layer. The measured heat flux q is proportional to the temperature difference across the resistance layer q= k(sub g)/delta(sub g) x (t(sub 1) - T(sub 2)), where k(sub g) is the thermal conductivity and delta (sub g) is the thickness of the thermal resistance layer. Because the gages are sputter coated directly onto the surface, their total thickness is less than 2 micrometers, which is two orders of magnitude thinner than previous gages. The resulting temperature difference across the thermal resistance layer (delta is less than 1 micrometer) is very small even at high heat fluxes. To generate a measurable signal many thermocouple pairs are put in series to form a differential thermopile. The combination of series thermocouple junctions and thin-film design creates a gage with very attractive characteristics. It is not only physically non-intrusive to the flow, but also causes minimal disruption of the surface temperature. Because it is so thin, the response time is less than 20 microsec. Consequently, the frequency response is flat from 0 to over 50 kHz. Moreover, the signal of the Heat Flux Microsensor is directly proportional to the heat flux. Therefore, it can easily be used in both steady and transient flows, and it measures both the steady and unsteady components of the surface heat flux. A version of the Heat Flux Microsensor has been developed to meet the harsh demands of combustion environments. These gages use platinum and platinum-10 percent rhodium as the thermoelectric materials. The thermal resistance layer is silicon monoxide and a protective coating of Al2O3 is deposited on top of the sensor. The

  4. Air temperature measurements based on the speed of sound to compensate long distance interferometric measurements

    Directory of Open Access Journals (Sweden)

    Astrua Milena

    2014-01-01

    Full Text Available A method to measure the real time temperature distribution along an interferometer path based on the propagation of acoustic waves is presented. It exploits the high sensitivity of the speed of sound in air to the air temperature. In particular, it takes advantage of a special set-up where the generation of the acoustic waves is synchronous with the amplitude modulation of a laser source. A photodetector converts the laser light to an electronic signal considered as reference, while the incoming acoustic waves are focused on a microphone and generate a second signal. In this condition, the phase difference between the two signals substantially depends on the temperature of the air volume interposed between the sources and the receivers. The comparison with the traditional temperature sensors highlighted the limit of the latter in case of fast temperature variations and the advantage of a measurement integrated along the optical path instead of a sampling measurement. The capability of the acoustic method to compensate the interferometric distance measurements due to air temperature variations has been demonstrated for distances up to 27 m.

  5. Are Sea Surface Temperature satellite measurements reliable proxies of lagoon temperature in the South Pacific?

    Science.gov (United States)

    Van Wynsberge, Simon; Menkes, Christophe; Le Gendre, Romain; Passfield, Teuru; Andréfouët, Serge

    2017-12-01

    In remote coral reef environments, lagoon and reef in situ measurements of temperature are scarce. Sea Surface Temperature (SST) measured by satellite has been frequently used as a proxy of the lagoon temperature experienced by coral reef organisms (TL) especially during coral bleaching events. However, the link between SST and TL is poorly characterized. First, we compared the correlation between various SST series and TL from 2012 to 2016 in three atolls and one island in the Central South Pacific Ocean. Simple linear correlation between SST and TL ranged between 0.44 and 0.97 depending on lagoons, localities of sensors, and type of SST data. High-resolution-satellite-measurements of SST inside the lagoons did not outperform oceanic SST series, suggesting that SST products are not adapted for small lagoons. Second, we modelled the difference between oceanic SST and TL as a function of the drivers of lagoon water renewal and mixing, namely waves, tide, wind, and season. The multivariate models reduced significantly the bias between oceanic SST and TL. In atoll lagoons, and probably in other hydrodynamically semi-open systems, a correction taking into account these factors is necessary when SST are used to characterize organisms' thermal stress thresholds.

  6. Hydroxyl temperature and intensity measurements during noctilucent cloud displays

    Directory of Open Access Journals (Sweden)

    M. J. Taylor

    1995-10-01

    Full Text Available Two Fourier transform spectrometers have been used to investigate the properties of the near-infrared hydroxyl (OH nightglow emission under high-latitude summertime conditions and any association with noctilucent clouds (NLCs. The measurements were made from Poker Flat Research Range, Alaska (65.1°N, 147.5°W, during August 1986. Simultaneous photographic observations of the northern twilight sky were made from Gulkana, Alaska (62.2°N, 145.5°W, approximately 340 km to the south to establish the presence of NLCs over the spectrometer site. Data exhibiting significant short-term variations in the relative intensity (as much as 50–100% and rotational temperature (typically 5–15 K were recorded on six occasions when NLCs were observed. Joint measurements were also obtained on several "cloud-free" nights. No obvious relationship was found linking the mean OH intensity or its variation with the occurrence of NLCs. However, a clear tendency was found for the mean OH temperature to be lower on NLC nights than on cloud-free nights. In particular, a significant fraction of the OH(3–1 band spectra recorded by each instrument (16–57% exhibited temperatures below ~154 K on NLC nights compared with <3% on cloud-free nights. This result is qualitatively consistent with current models for ice particle nucleation and growth, but the mean OH temperature on NLC nights (~156 K was significantly higher than would be expected for long-term particle growth in this region. These observations raise questions concerning the expected proximity of the high-latitude, summertime OH layer and the NLC growth region.

  7. Hydroxyl temperature and intensity measurements during noctilucent cloud displays

    Directory of Open Access Journals (Sweden)

    M. J. Taylor

    Full Text Available Two Fourier transform spectrometers have been used to investigate the properties of the near-infrared hydroxyl (OH nightglow emission under high-latitude summertime conditions and any association with noctilucent clouds (NLCs. The measurements were made from Poker Flat Research Range, Alaska (65.1°N, 147.5°W, during August 1986. Simultaneous photographic observations of the northern twilight sky were made from Gulkana, Alaska (62.2°N, 145.5°W, approximately 340 km to the south to establish the presence of NLCs over the spectrometer site. Data exhibiting significant short-term variations in the relative intensity (as much as 50–100% and rotational temperature (typically 5–15 K were recorded on six occasions when NLCs were observed. Joint measurements were also obtained on several "cloud-free" nights. No obvious relationship was found linking the mean OH intensity or its variation with the occurrence of NLCs. However, a clear tendency was found for the mean OH temperature to be lower on NLC nights than on cloud-free nights. In particular, a significant fraction of the OH(3–1 band spectra recorded by each instrument (16–57% exhibited temperatures below ~154 K on NLC nights compared with <3% on cloud-free nights. This result is qualitatively consistent with current models for ice particle nucleation and growth, but the mean OH temperature on NLC nights (~156 K was significantly higher than would be expected for long-term particle growth in this region. These observations raise questions concerning the expected proximity of the high-latitude, summertime OH layer and the NLC growth region.

  8. An efficient simulated annealing algorithm for the redundancy allocation problem with a choice of redundancy strategies

    International Nuclear Information System (INIS)

    Chambari, Amirhossain; Najafi, Amir Abbas; Rahmati, Seyed Habib A.; Karimi, Aida

    2013-01-01

    The redundancy allocation problem (RAP) is an important reliability optimization problem. This paper studies a specific RAP in which redundancy strategies are chosen. To do so, the choice of the redundancy strategies among active and cold standby is considered as decision variables. The goal is to select the redundancy strategy, component, and redundancy level for each subsystem such that the system reliability is maximized. Since RAP is a NP-hard problem, we propose an efficient simulated annealing algorithm (SA) to solve it. In addition, to evaluating the performance of the proposed algorithm, it is compared with well-known algorithms in the literature for different test problems. The results of the performance analysis show a relatively satisfactory efficiency of the proposed SA algorithm

  9. Probability Model for Data Redundancy Detection in Sensor Networks

    Directory of Open Access Journals (Sweden)

    Suman Kumar

    2009-01-01

    Full Text Available Sensor networks are made of autonomous devices that are able to collect, store, process and share data with other devices. Large sensor networks are often redundant in the sense that the measurements of some nodes can be substituted by other nodes with a certain degree of confidence. This spatial correlation results in wastage of link bandwidth and energy. In this paper, a model for two associated Poisson processes, through which sensors are distributed in a plane, is derived. A probability condition is established for data redundancy among closely located sensor nodes. The model generates a spatial bivariate Poisson process whose parameters depend on the parameters of the two individual Poisson processes and on the distance between the associated points. The proposed model helps in building efficient algorithms for data dissemination in the sensor network. A numerical example is provided investigating the advantage of this model.

  10. Low-redundancy linear arrays in mirrored interferometric aperture synthesis.

    Science.gov (United States)

    Zhu, Dong; Hu, Fei; Wu, Liang; Li, Jun; Lang, Liang

    2016-01-15

    Mirrored interferometric aperture synthesis (MIAS) is a novel interferometry that can improve spatial resolution compared with that of conventional IAS. In one-dimensional (1-D) MIAS, antenna array with low redundancy has the potential to achieve a high spatial resolution. This Letter presents a technique for the direct construction of low-redundancy linear arrays (LRLAs) in MIAS and derives two regular analytical patterns that can yield various LRLAs in short computation time. Moreover, for a better estimation of the observed scene, a bi-measurement method is proposed to handle the rank defect associated with the transmatrix of those LRLAs. The results of imaging simulation demonstrate the effectiveness of the proposed method.

  11. Measurement of the temperature coefficient of ratio transformers

    Science.gov (United States)

    Briggs, Matthew E.; Gammon, Robert W.; Shaumeyer, J. N.

    1993-01-01

    We have measured the temperature coefficient of the output of several ratio transformers at ratios near 0.500,000 using an ac bridge and a dual-phase, lock-in amplifier. The two orthogonal output components were each resolved to +/- ppb of the bridge drive signal. The results for three commercial ratio transformers between 20 and 50 C range from 0.5 to 100 ppb/K for the signal component in phase with the bridge drive, and from 4 to 300 ppb/K for the quadrature component.

  12. Instantaneous temperature field measurements using planar laser-induced fluorescence.

    Science.gov (United States)

    Seitzman, J M; Kychakoff, G; Hanson, R K

    1985-09-01

    A single-pulse, laser-induced-fluorescence diagnostic for the measurement of two-dimensional temperature fields in combustion flows is described. The method uses sheet illumination from a tunable laser to excite planar laserinduced fluorescence in a stable tracer molecule, seeded at constant mole fraction into the flow field. The temporal resolution of this technique is determined by the laser pulse length. Experimental results are presented for a rodstabilized, premixed methane-air flame, using the Q(1) (22) line of the nitric oxide A(2) Sigma(+) (v = 0) ? X(2)II((1/2))(v = 0) transition (lambda approximately 225.6 nm).

  13. Noncontact measurement of high temperature using optical fiber sensors

    Science.gov (United States)

    Claus, R. O.

    1990-01-01

    The primary goal of this research program was the investigation and application of noncontact temperature measurement techniques using optical techniques and optical fiber methods. In particular, a pyrometer utilizing an infrared optical light pipe and a multiwavelength filtering approach was designed, revised, and tested. This work was motivated by the need to measure the temperatures of small metallic pellets (approximately 3 mm diameter) in free fall at the Microgravity Materials Processing Drop Tube at NASA Marshall Space Flight Center. In addition, research under this program investigated the adaptation of holography technology to optical fiber sensors, and also examined the use of rare-earth dopants in optical fibers for use in measuring temperature. The pyrometer development effort involved both theoretical analysis and experimental tests. For the analysis, a mathematical model based on radiative transfer principles was derived. Key parameter values representative of the drop tube system, such as particle size, tube diameter and length, and particle temperature, were used to determine an estimate of the radiant flux that will be incident on the face of an optical fiber or light pipe used to collect radiation from the incandescent falling particle. An extension of this work examined the advantage of inclining or tilting the collecting fiber to increase the time that the falling particle remains in the fiber field-of-view. Those results indicate that increases in total power collected of about 15 percent may be realized by tilting the fiber. In order to determine the suitability of alternative light pipes and optical fibers, and experimental set-up for measuring the transmittance and insertion loss of infrared fibers considered for use in the pyrometer was assembled. A zirconium fluoride optical fiber and several bundles of hollow core fiber of varying diameters were tested. A prototype two-color pyrometer was assembled and tested at Virginia Tech, and then

  14. Interaction control of a redundant mobile manipulator

    International Nuclear Information System (INIS)

    Chung, J.H.; Velinsky, S.A.; Hess, R.A.

    1998-01-01

    This paper discusses the modeling and control of a spatial mobile manipulator that consists of a robotic manipulator mounted on a wheeled mobile platform. The Lagrange-d'Alembert formulation is used to obtain a concise description of the dynamics of the system, which is subject to nonholonomic constraints. The complexity of the model is increased by introducing kinematic redundancy, which is created when a multilinked manipulator is used. The kinematic redundancy is resolved by decomposing the mobile manipulator into two subsystems: the mobile platform and the manipulator. The redundancy resolution scheme employs a nonlinear interaction-control algorithm, which is developed and applied to coordinate the two subsystems' controllers. The subsystem controllers are independently designed, based on each subsystem's dynamic characteristics. Simulation results show the promise of the developed algorithm

  15. Motion compensation via redundant-wavelet multihypothesis.

    Science.gov (United States)

    Fowler, James E; Cui, Suxia; Wang, Yonghui

    2006-10-01

    Multihypothesis motion compensation has been widely used in video coding with previous attention focused on techniques employing predictions that are diverse spatially or temporally. In this paper, the multihypothesis concept is extended into the transform domain by using a redundant wavelet transform to produce multiple predictions that are diverse in transform phase. The corresponding multiple-phase inverse transform implicitly combines the phase-diverse predictions into a single spatial-domain prediction for motion compensation. The performance advantage of this redundant-wavelet-multihypothesis approach is investigated analytically, invoking the fact that the multiple-phase inverse involves a projection that significantly reduces the power of a dense-motion residual modeled as additive noise. The analysis shows that redundant-wavelet multihypothesis is capable of up to a 7-dB reduction in prediction-residual variance over an equivalent single-phase, single-hypothesis approach. Experimental results substantiate the performance advantage for a block-based implementation.

  16. Acoustic levitator for containerless measurements on low temperature liquids

    Energy Technology Data Exchange (ETDEWEB)

    Benmore, Chris J [Argonne National Laboratory (ANL); Weber, Richard [Argonne National Laboratory (ANL); Neuefeind, Joerg C [ORNL; Rey, Charles A A [Charles Ray, Inc.

    2009-01-01

    A single-axis acoustic levitator was constructed and used to levitate liquid and solid drops at temperatures from -40 to +40 C. The levitator consisted of: (i) two acoustic transducers mounted on a rigid vertical support that was bolted to an optical breadboard, (ii) a acoustic power supply that controlled acoustic intensity, relative phase of the drive to the transducers, and could modulate the acoustic forces at frequencies up to 1kHz, (iii) a video camera, and (iv) a system for providing a stream of controlled temperature gas flow over the sample. The acoustic transducers were operated at their resonant frequency of ~ 22 kHz and could produce sound pressure levels up to 160 dB. The force applied by the acoustic field could be modulated using a frequency generator to excite oscillations in the sample. Sample temperature was controlled using a modified Cryostream Plus and measured using thermocouples and an infrared thermal imager. The levitator was installed at x-ray beamline 11 ID-C at the Advanced Photon Source and used to investigate the structure of supercooled liquids.

  17. Temporal and spatial assessments of minimum air temperature using satellite surface temperature measurements in Massachusetts, USA.

    Science.gov (United States)

    Kloog, Itai; Chudnovsky, Alexandra; Koutrakis, Petros; Schwartz, Joel

    2012-08-15

    Although meteorological stations provide accurate air temperature observations, their spatial coverage is limited and thus often insufficient for epidemiological studies. Satellite data expand spatial coverage, enhancing our ability to estimate near surface air temperature (Ta). However, the derivation of Ta from surface temperature (Ts) measured by satellites is far from being straightforward. In this study, we present a novel approach that incorporates land use regression, meteorological variables and spatial smoothing to first calibrate between Ts and Ta on a daily basis and then predict Ta for days when satellite Ts data were not available. We applied mixed regression models with daily random slopes to calibrate Moderate Resolution Imaging Spectroradiometer (MODIS) Ts data with monitored Ta measurements for 2003. Then, we used a generalized additive mixed model with spatial smoothing to estimate Ta in days with missing Ts. Out-of-sample tenfold cross-validation was used to quantify the accuracy of our predictions. Our model performance was excellent for both days with available Ts and days without Ts observations (mean out-of-sample R(2)=0.946 and R(2)=0.941 respectively). Furthermore, based on the high quality predictions we investigated the spatial patterns of Ta within the study domain as they relate to urban vs. non-urban land uses. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Estimating temperature reactivity coefficients by experimental procedures combined with isothermal temperature coefficient measurements and dynamic identification

    International Nuclear Information System (INIS)

    Tsuji, Masashi; Aoki, Yukinori; Shimazu, Yoichiro; Yamasaki, Masatoshi; Hanayama, Yasushi

    2006-01-01

    A method to evaluate the moderator coefficient (MTC) and the Doppler coefficient through experimental procedures performed during reactor physics tests of PWR power plants is proposed. This method combines isothermal temperature coefficient (ITC) measurement experiments and reactor power transient experiments at low power conditions for dynamic identification. In the dynamic identification, either one of temperature coefficients can be determined in such a way that frequency response characteristics of the reactivity change observed by a digital reactivity meter is reproduced from measured data of neutron count rate and the average coolant temperature. The other unknown coefficient can also be determined by subtracting the coefficient obtained from the dynamic identification from ITC. As the proposed method can directly estimate the Doppler coefficient, the applicability of the conventional core design codes to predict the Doppler coefficient can be verified for new types of fuels such as mixed oxide fuels. The digital simulation study was carried out to show the feasibility of the proposed method. The numerical analysis showed that the MTC and the Doppler coefficient can be estimated accurately and even if there are uncertainties in the parameters of the reactor kinetics model, the accuracies of the estimated values are not seriously impaired. (author)

  19. Exhaust Gas Temperature Measurements in Diagnostics of Turbocharged Marine Internal Combustion Engines Part I Standard Measurements

    Directory of Open Access Journals (Sweden)

    Korczewski Zbigniew

    2015-01-01

    Full Text Available The article discusses the problem of diagnostic informativeness of exhaust gas temperature measurements in turbocharged marine internal combustion engines. Theoretical principles of the process of exhaust gas flow in turbocharger inlet channels are analysed in its dynamic and energetic aspects. Diagnostic parameters are defined which enable to formulate general evaluation of technical condition of the engine based on standard online measurements of the exhaust gas temperature. A proposal is made to extend the parametric methods of diagnosing workspaces in turbocharged marine engines by analysing time-histories of enthalpy changes of the exhaust gas flowing to the turbocompressor turbine. Such a time-history can be worked out based on dynamic measurements of the exhaust gas temperature, performed using a specially designed sheathed thermocouple.

  20. Exhaust Gas Temperature Measurements in Diagnostics of Turbocharged Marine Internal Combustion Engines Part II Dynamic Measurements

    Directory of Open Access Journals (Sweden)

    Korczewski Zbigniew

    2016-01-01

    Full Text Available The second part of the article describes the technology of marine engine diagnostics making use of dynamic measurements of the exhaust gas temperature. Little-known achievements of Prof. S. Rutkowski of the Naval College in Gdynia (now: Polish Naval Academy in this area are presented. A novel approach is proposed which consists in the use of the measured exhaust gas temperature dynamics for qualitative and quantitative assessment of the enthalpy flux of successive pressure pulses of the exhaust gas supplying the marine engine turbocompressor. General design assumptions are presented for the measuring and diagnostic system which makes use of a sheathed thermocouple installed in the engine exhaust gas manifold. The corrected thermal inertia of the thermocouple enables to reproduce a real time-history of exhaust gas temperature changes.

  1. Ambient temperature field measuring system for LHC superconducting dipoles

    International Nuclear Information System (INIS)

    Billan, J.; De Panfilis, S.; Giloteaux, D.; Pagano, O.

    1996-01-01

    It is foreseen to perform acceptance tests including field measurements of the collared coils assembly of the LHC superconducting dipoles to estimate, at an early production stage, the possible significant deviations from the expected multipole component value of these magnets. A sensitive measuring probe and efficient data acquisition are the consequence of a low magnetizing current necessary to limit the coils heating. This demands a high signals sensitivity and an enhanced signal-to-noise ratio to retrieve the higher multipole component. Moreover, the correlation with the multipoles content of the magnets at cryogenic temperature and nominal excitation current need to be identified before the manufacturing process may continue. The field probe of the mole-type is equipped with three radial rotating search coils, an angular encoder and gravity sensor. It has been designed to slide inside the bore of the dipole coils and to measure the local field at fixed positions. The field analysis resulting in terms of multipole components, field direction and field integrals, measured on four 10 m long, twin-aperture LHC dipole prototypes, will be described together with the performance of the measuring method

  2. Redundancy Elimination in DTN via ACK Mechanism

    Directory of Open Access Journals (Sweden)

    Xiqing Zhang

    2015-08-01

    Full Text Available The traditional routing protocols for delay tolerant networks (DTN usually take the strategy of spreading multiple copies of one message to the networks. When one copy reaches destination, the transmission of other copies not only waste the bandwidth but also deprive other messages of the opportunities for transmission. This paper brings up a mechanism to eliminate the redundant copies. By adding an acknowledge field to the packet header to delete redundant copies, it can degrade the network overhead while improve the delivery ratio. Simulation results confirm that the proposed method can improve the performance of epidemic and Spray and Wait routing protocol.

  3. The Rover Environmental Monitoring Station Ground Temperature Sensor: A Pyrometer for Measuring Ground Temperature on Mars

    Directory of Open Access Journals (Sweden)

    Miguel Ramos

    2010-10-01

    Full Text Available We describe the parameters that drive the design and modeling of the Rover Environmental Monitoring Station (REMS Ground Temperature Sensor (GTS, an instrument aboard NASA’s Mars Science Laboratory, and report preliminary test results. REMS GTS is a lightweight, low-power, and low cost pyrometer for measuring the Martian surface kinematic temperature. The sensor’s main feature is its innovative design, based on a simple mechanical structure with no moving parts. It includes an in-flight calibration system that permits sensor recalibration when sensor sensitivity has been degraded by deposition of dust over the optics. This paper provides the first results of a GTS engineering model working in a Martian-like, extreme environment.

  4. Effect of In-Situ Cure on Measurement of Glass Transition Temperatures in High-Temperature Thermosetting Polymers (Briefing Charts)

    Science.gov (United States)

    2015-05-20

    TEMPERATURES IN HIGH-TEMPERATURE THERMOSETTING POLYMERS 5a. CONTRACT NUMBER In-House 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d...temperature thermosetting polymer via dynamic mechanical analysis alone. These difficulties result from the residual cure of samples heated beyond their...98) Prescribed by ANSI Std. 239.18 Effect of In-Situ Cure on Measurement of Glass Transition Temperatures in High-Temperature Thermosetting

  5. Development of a method for estimating oesophageal temperature by multi-locational temperature measurement inside the external auditory canal

    Science.gov (United States)

    Nakada, Hirofumi; Horie, Seichi; Kawanami, Shoko; Inoue, Jinro; Iijima, Yoshinori; Sato, Kiyoharu; Abe, Takeshi

    2017-09-01

    We aimed to develop a practical method to estimate oesophageal temperature by measuring multi-locational auditory canal temperatures. This method can be applied to prevent heatstroke by simultaneously and continuously monitoring the core temperatures of people working under hot environments. We asked 11 healthy male volunteers to exercise, generating 80 W for 45 min in a climatic chamber set at 24, 32 and 40 °C, at 50% relative humidity. We also exposed the participants to radiation at 32 °C. We continuously measured temperatures at the oesophagus, rectum and three different locations along the external auditory canal. We developed equations for estimating oesophageal temperatures from auditory canal temperatures and compared their fitness and errors. The rectal temperature increased or decreased faster than oesophageal temperature at the start or end of exercise in all conditions. Estimated temperature showed good similarity with oesophageal temperature, and the square of the correlation coefficient of the best fitting model reached 0.904. We observed intermediate values between rectal and oesophageal temperatures during the rest phase. Even under the condition with radiation, estimated oesophageal temperature demonstrated concordant movement with oesophageal temperature at around 0.1 °C overestimation. Our method measured temperatures at three different locations along the external auditory canal. We confirmed that the approach can credibly estimate the oesophageal temperature from 24 to 40 °C for people performing exercise in the same place in a windless environment.

  6. Implementation of Moderator Circulation Test Temperature Measurement System

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Yeong Muk; Hong, Seok Boong; Kim, Min Seok; Choi, Hwa Rim [KAERI, Daejeon (Korea, Republic of); Kim, Hyung Shin [Chungnam University, Daejeon (Korea, Republic of)

    2016-05-15

    Moderator Circulation Test(MCT) facility is 1/4 scale facility designed to reproduce the important characteristics of moderator circulation in a CANDU6 calandria under a range of operating conditions. MCT is an equipment with 380 acrylic pipes instead of the heater rods and a preliminary measurement of velocity field using PIV(Particle Image Velocimetry) is performed under the iso-thermal test conditions. The Korea Atomic Energy Research Institute (KAERI) started implementation of MCT Temperature Measurement System (TMS) using multiple infrared sensors. To control multiple infrared sensors, MCT TMS is implemented using National Instruments (NI) LabVIEW programming language. The MCT TMS is implemented to measure sensor data of multiple infrared sensors using the LabVIEW. The 35 sensor pipes of MCT TMS are divided into 2 ports to meet the minimum measurement time of 0.2 seconds. The software of MCT TMS is designed using collection function and processing function. The MCT TMS has the function of monitoring the states of multiple infrared sensors. The GUI screen of MCT TMS is composed of sensor pipe categories for user.

  7. Implementation of Moderator Circulation Test Temperature Measurement System

    International Nuclear Information System (INIS)

    Lim, Yeong Muk; Hong, Seok Boong; Kim, Min Seok; Choi, Hwa Rim; Kim, Hyung Shin

    2016-01-01

    Moderator Circulation Test(MCT) facility is 1/4 scale facility designed to reproduce the important characteristics of moderator circulation in a CANDU6 calandria under a range of operating conditions. MCT is an equipment with 380 acrylic pipes instead of the heater rods and a preliminary measurement of velocity field using PIV(Particle Image Velocimetry) is performed under the iso-thermal test conditions. The Korea Atomic Energy Research Institute (KAERI) started implementation of MCT Temperature Measurement System (TMS) using multiple infrared sensors. To control multiple infrared sensors, MCT TMS is implemented using National Instruments (NI) LabVIEW programming language. The MCT TMS is implemented to measure sensor data of multiple infrared sensors using the LabVIEW. The 35 sensor pipes of MCT TMS are divided into 2 ports to meet the minimum measurement time of 0.2 seconds. The software of MCT TMS is designed using collection function and processing function. The MCT TMS has the function of monitoring the states of multiple infrared sensors. The GUI screen of MCT TMS is composed of sensor pipe categories for user

  8. Selective solar absorber emittance measurement at elevated temperature

    Science.gov (United States)

    Giraud, Philémon; Braillon, Julien; Raccurt, Olivier

    2017-06-01

    Durability of solar components for CSP (Concentrated Solar Power Plant) technologies is a key point to lower cost and ensure their large deployment. These technologies concentrated the solar radiation by means of mirrors on a receiver tube where it is collected as thermal energy. The absorbers are submitted to strong environmental constraints and the degradation of their optical properties (emittance and solar absorbance) have a direct impact on performance. The characterization of a material in such condition is complicated and requires advanced apparatuses, and different measurement methods exist for the determination of the two quantities of relevance regarding an absorber, which are its emittance and its solar absorbance. The objective is to develop new optical equipment for measure the emittance of this solar absorber at elevated temperature. In this paper, we present an optical bench developed for emittance measurement on absorbers is conditions of use. Results will be shown, with a discussion of some factors of influence over this measurement and how to control them.

  9. Electrochemical corrosion potential and noise measurement in high temperature water

    International Nuclear Information System (INIS)

    Fong, Clinton; Chen, Yaw-Ming; Chu, Fang; Huang, Chia-Shen

    2000-01-01

    Hydrogen water chemistry (HWC) is one of the most important methods in boiling water reactor(BWR) system to mitigate and prevent stress corrosion cracking (SCC) problems of stainless steel components. Currently, the effectiveness of HWC in each BWR is mainly evaluated by the measurement of electrochemical corrosion potentials (ECP) and on-line monitoring of SCC behaviors of stainless steels. The objective of this work was to evaluate the characteristics and performance of commercially available high temperature reference electrodes. In addition, SCC monitoring technique based on electrochemical noise analysis (ECN) was also tested to examine its crack detection capability. The experimental work on electrochemical corrosion potential (ECP) measurements reveals that high temperature external Ag/AgCl reference electrode of highly dilute KCl electrolyte can adequately function in both NWC and HWC environments. The high dilution external Ag/AgCl electrode can work in conjunction with internal Ag/AgCl reference electrode, and Pt electrode to ensure the ECP measurement reliability. In simulated BWR environment, the electrochemical noise tests of SCC were carried out with both actively and passively loaded specimens of type 304 stainless steel with various electrode arrangements. From the coupling current and corrosion potential behaviors of the passive loading tests during immersion test, it is difficult to interpret the general state of stress corrosion cracking based on the analytical results of overall current and potential variations, local pulse patterns, statistical characteristics, or power spectral density of electrochemical noise signals. However, more positive SCC indication was observed in the power spectral density analysis. For aqueous environments of high solution impedance, successful application of electrochemical noise technique for SCC monitoring may require further improvement in specimen designs and analytical methods to enhance detection sensitivity

  10. AC measurements on uranium doped high temperature superconductors

    International Nuclear Information System (INIS)

    Eisterer, M.

    1999-11-01

    The subject of this thesis is the influence of fission tracks on the superconducting properties of melt textured Y-123. The critical current densities, the irreversibility lines and the transition temperature were determined by means of ac measurements. The corresponding ac techniques are explored in detail. Deviations of the ac signal from the expectations according to the Bean model were explained by the dependence of the shielding currents on the electric field. This explanation is supported by the influence of the ac amplitude and frequency on the critical current density but also by a comparison of the obtained data with other experimental techniques. Y-123 has to be doped with uranium in order to induce fission tracks. Uranium forms normal conducting clusters, which are nearly spherical, with a diameter of about 300 nm. Fission of uranium-235 by thermal neutrons creates two high energy ions with a total energy of about 160 MeV. Each of these fission products induces a linear defect with a diameter of about 10 nm. The length of one fission track is 2-4 μm. At 77 K the critical current density is enhanced by the pinning action of the uranium clusters, compared to undoped samples. With decreasing temperature this influence becomes negligible. The critical current densities are strongly enhanced due to the irradiation. At low magnetic fields we find extremely high values for melt textured materials, e.g. 2.5x10 9 Am -2 at 77 K and 0.25 T or 6x10 10 Am -2 at 5 K. Since the critical current was found to be inverse proportional to the square root of the applied magnetic field it decreases rapidly as the field increases. This behavior is predicted by simple theoretical considerations, but is only valid at low temperatures as well as in low magnetic fields at high temperatures. At high fields the critical current drops more rapidly. The irreversibility lines are only slightly changed by this irradiation technique. Only a small shift to higher fields and temperatures

  11. Analysis of singularity in redundant manipulators

    International Nuclear Information System (INIS)

    Watanabe, Koichi

    2000-03-01

    In the analysis of arm positions and configurations of redundant manipulators, the singularity avoidance problems are important themes. This report presents singularity avoidance computations of a 7 DOF manipulator by using a computer code based on human-arm models. The behavior of the arm escaping from the singular point can be identified satisfactorily through the use of 3-D plotting tools. (author)

  12. Coded aperture imaging with uniformly redundant arrays

    International Nuclear Information System (INIS)

    Fenimore, E.E.; Cannon, T.M.

    1980-01-01

    A system is described which uses uniformly redundant arrays to image non-focusable radiation. The array is used in conjunction with a balanced correlation technique to provide a system with no artifacts so that virtually limitless signal-to-noise ratio is obtained with high transmission characteristics. The array is mosaicked to reduce required detector size over conventional array detectors. 15 claims

  13. Motion control of musculoskeletal systems with redundancy.

    Science.gov (United States)

    Park, Hyunjoo; Durand, Dominique M

    2008-12-01

    Motion control of musculoskeletal systems for functional electrical stimulation (FES) is a challenging problem due to the inherent complexity of the systems. These include being highly nonlinear, strongly coupled, time-varying, time-delayed, and redundant. The redundancy in particular makes it difficult to find an inverse model of the system for control purposes. We have developed a control system for multiple input multiple output (MIMO) redundant musculoskeletal systems with little prior information. The proposed method separates the steady-state properties from the dynamic properties. The dynamic control uses a steady-state inverse model and is implemented with both a PID controller for disturbance rejection and an artificial neural network (ANN) feedforward controller for fast trajectory tracking. A mechanism to control the sum of the muscle excitation levels is also included. To test the performance of the proposed control system, a two degree of freedom ankle-subtalar joint model with eight muscles was used. The simulation results show that separation of steady-state and dynamic control allow small output tracking errors for different reference trajectories such as pseudo-step, sinusoidal and filtered random signals. The proposed control method also demonstrated robustness against system parameter and controller parameter variations. A possible application of this control algorithm is FES control using multiple contact cuff electrodes where mathematical modeling is not feasible and the redundancy makes the control of dynamic movement difficult.

  14. On Redundancy in Describing Linguistic Systems

    Directory of Open Access Journals (Sweden)

    Vladimir Borissov Pericliev

    2015-12-01

    Full Text Available On Redundancy in Describing Linguistic Systems The notion of system of linguistic elements figures prominently in most post-Saussurian linguistics up to the present. A “system” is the network of the contrastive (or, distinctive features each element in the system bears to the remaining elements. The meaning (valeur of each element in the system is the set of features that are necessary and jointly sufficient to distinguish this element from all others. The paper addresses the problems of “redundancy”, i.e. the occurrence of features that are not strictly necessary in describing an element in a system. Redundancy is shown to smuggle into the description of linguistic systems, this infelicitous practice illustrated with some examples from the literature (e.g. the classical phonemic analysis of Russian by Cherry, Halle, and Jakobson, 1953. The logic and psychology of the occurrence of redundancy are briefly sketched and it is shown that, in addition to some other problems, redundancy leads to a huge and unresolvable ambiguity of descriptions of linguistic systems (the Buridan’s ass problem.

  15. Impedance Control of a Redundant Parallel Manipulator

    DEFF Research Database (Denmark)

    Méndez, Juan de Dios Flores; Schiøler, Henrik; Madsen, Ole

    2017-01-01

    This paper presents the design of Impedance Control to a redundantly actuated Parallel Kinematic Manipulator. The proposed control is based on treating each limb as a single system and their connection through the internal interaction forces. The controller introduces a stiffness and damping...

  16. REDUNDANT ARRAY CONFIGURATIONS FOR 21 cm COSMOLOGY

    Energy Technology Data Exchange (ETDEWEB)

    Dillon, Joshua S.; Parsons, Aaron R., E-mail: jsdillon@berkeley.edu [Department of Astronomy, UC Berkeley, Berkeley, CA (United States)

    2016-08-01

    Realizing the potential of 21 cm tomography to statistically probe the intergalactic medium before and during the Epoch of Reionization requires large telescopes and precise control of systematics. Next-generation telescopes are now being designed and built to meet these challenges, drawing lessons from first-generation experiments that showed the benefits of densely packed, highly redundant arrays—in which the same mode on the sky is sampled by many antenna pairs—for achieving high sensitivity, precise calibration, and robust foreground mitigation. In this work, we focus on the Hydrogen Epoch of Reionization Array (HERA) as an interferometer with a dense, redundant core designed following these lessons to be optimized for 21 cm cosmology. We show how modestly supplementing or modifying a compact design like HERA’s can still deliver high sensitivity while enhancing strategies for calibration and foreground mitigation. In particular, we compare the imaging capability of several array configurations, both instantaneously (to address instrumental and ionospheric effects) and with rotation synthesis (for foreground removal). We also examine the effects that configuration has on calibratability using instantaneous redundancy. We find that improved imaging with sub-aperture sampling via “off-grid” antennas and increased angular resolution via far-flung “outrigger” antennas is possible with a redundantly calibratable array configuration.

  17. Beyond redundancy how geographic redundancy can improve service availability and reliability of computer-based systems

    CERN Document Server

    Bauer, Eric; Eustace, Dan

    2012-01-01

    "While geographic redundancy can obviously be a huge benefit for disaster recovery, it is far less obvious what benefit is feasible and likely for more typical non-catastrophic hardware, software, and human failures. Georedundancy and Service Availability provides both a theoretical and practical treatment of the feasible and likely benefits of geographic redundancy for both service availability and service reliability. The text provides network/system planners, IS/IT operations folks, system architects, system engineers, developers, testers, and other industry practitioners with a general discussion about the capital expense/operating expense tradeoff that frames system redundancy and georedundancy"--

  18. Experimental evaluation of IGBT junction temperature measurement via peak gate current

    DEFF Research Database (Denmark)

    Baker, Nick; Munk-Nielsen, Stig; Iannuzzo, Francesco

    2015-01-01

    Temperature sensitive electrical parameters allow junction temperature measurements on power semiconductors without modification to module packaging. The peak gate current has recently been proposed for IGBT junction temperature measurement and relies on the temperature dependent resistance...... of the gate pad. Consequently, a consideration of chip geometry and location of the gate pad is required before interpreting temperature data from this method. Results are also compared with a traditional electrical temperature measurement method: the voltage drop under low current....

  19. Electron temperature measurements of FRX-C/LSM

    International Nuclear Information System (INIS)

    Rej, D.J.

    1989-01-01

    The electron temperature T/sub e/ has been measured with Thomson scattering field-reversed configurations (FRCs) on the Los Alamos FRX-C/LSM experiment. FRCs formed and trapped in-situ in the θ-pinch source are studied. These experiments mark the first comprehensive FRC T/sub e/ measurements in over five years with data gathered on over 400 discharges. Measurements are performed at a single point in space and time on each discharge. The Thomson scattering diagnostic consist of a Q-switched ruby laser focused from one end to a point 0.2 m from the axial midplane of the θ-pinch coil and at radius of either 0.00 or 0.10 m. Scattered light is collected, dispersed and detected with a 7-channel, triple-grating polychromator configured to detect light wavelengths between 658 and 692 nm. Photomultiplier currents are measured with gated A/D converters, with plasma background signals recorded 100-ns before and 100-ns after the laser pulse. Electron temperatures are measured at either radial position during the time interval, 10 ≤ t ≤ 70 μs, between FRC formation and the onset of the n = 2 instability which usually terminates the discharge. A variety of plasma conditions have been produced by adjusting three external parameters: the initial deuterium fill pressure p/sub O/; the reversed bias magnetic field B/sub b/; and the external magnetic field B/sub w/. The fill-pressure scan has been performed at B/sub b/ ≅ 60 mT and B/sub w/ ≅ 0.4 T with p/sub o/ set at either 2, 3, 4 or 5 mtorr. The bias-field scan, 37 ≤ B/sub b/ ≤ 95 mT, has been performed at p/sub o/ = 3 mtorr and B/sub w/ ≅ 0.4 T. 7 refs., 3 figs., 3 tabs

  20. Assessment for Melting Temperature Measurement of Nucleic Acid by HRM.

    Science.gov (United States)

    Wang, Jing; Pan, Xiaoming; Liang, Xingguo

    2016-01-01

    High resolution melting (HRM), with a high sensitivity to distinguish the nucleic acid species with small variations, has been widely applied in the mutation scanning, methylation analysis, and genotyping. For the aim of extending HRM for the evaluation of thermal stability of nucleic acid secondary structures on sequence dependence, we investigated effects of the dye of EvaGreen, metal ions, and impurities (such as dNTPs) on melting temperature ( T m ) measurement by HRM. The accuracy of HRM was assessed as compared with UV melting method, and little difference between the two methods was found when the DNA T m was higher than 40°C. Both insufficiency and excessiveness of EvaGreen were found to give rise to a little bit higher T m , showing that the proportion of dye should be considered for precise T m measurement of nucleic acids. Finally, HRM method was also successfully used to measure T m s of DNA triplex, hairpin, and RNA duplex. In conclusion, HRM can be applied in the evaluation of thermal stability of nucleic acid (DNA or RNA) or secondary structural elements (even when dNTPs are present).

  1. High Temperature Dynamic Pressure Measurements Using Silicon Carbide Pressure Sensors

    Science.gov (United States)

    Okojie, Robert S.; Meredith, Roger D.; Chang, Clarence T.; Savrun, Ender

    2014-01-01

    Un-cooled, MEMS-based silicon carbide (SiC) static pressure sensors were used for the first time to measure pressure perturbations at temperatures as high as 600 C during laboratory characterization, and subsequently evaluated in a combustor rig operated under various engine conditions to extract the frequencies that are associated with thermoacoustic instabilities. One SiC sensor was placed directly in the flow stream of the combustor rig while a benchmark commercial water-cooled piezoceramic dynamic pressure transducer was co-located axially but kept some distance away from the hot flow stream. In the combustor rig test, the SiC sensor detected thermoacoustic instabilities across a range of engine operating conditions, amplitude magnitude as low as 0.5 psi at 585 C, in good agreement with the benchmark piezoceramic sensor. The SiC sensor experienced low signal to noise ratio at higher temperature, primarily due to the fact that it was a static sensor with low sensitivity.

  2. The application of microwave techniques to temperature measurement in biotelemetry

    International Nuclear Information System (INIS)

    Glajchen, M.

    1984-01-01

    The use of a microwave dielectric resonator for temperature measurement in Biotelemetry offers the advantage that a passive temperature telemeter can be used. The telemeter is powered by a source remote from the host creature, thus permitting greater miniaturisation of the implant than is possible with conventional techniques. This is essential, especially for application to small animals where the telemeter size and weight become critical. The design of the telemeter which is based upon a novel microwave technique, and the associated practical considerations are discussed. Included in this work is a criticism of initially promising ideas which after an in-depth investigation had to be disregarded. Although the transponder could not be built in its final form due to the unavailability of certain key materials, the transponder operation was tested and found to be successful. A specification of the transponder and transmitter requirements for a working system are included. A theoretical and experimental appraisal of dielectric resonators as miniature microwave filters, also forms a large part of this work. Dielectric resonators offer a significant volume reduction compared to air-filled metallic cavities, and simple coupling to microstrip combined with ease of tuning permits incorporation into Microwave Integrated Circuits. A computer program which can form the basis for a dielectric resonator filter design is provided, and some unusual results of tests on dielectric resonators are presented. It is believed that this will help to popularise and increase understanding of the dielectric resonator - which is an exciting, yet still emerging technology

  3. Improved Creep Measurements for Ultra-High Temperature Materials

    Science.gov (United States)

    Hyers, Robert W.; Ye, X.; Rogers, Jan R.

    2010-01-01

    Our team has developed a novel approach to measuring creep at extremely high temperatures using electrostatic levitation (ESL). This method has been demonstrated on niobium up to 2300 C, while ESL has melted tungsten (3400 C). This method has been extended to lower temperatures and higher stresses and applied to new materials, including a niobium-based superalloy, MASC. High-precision machined spheres of the sample are levitated in the NASA MSFC ESL, a national user facility and heated with a laser. The samples are rotated with an induction motor at up to 30,000 revolutions per second. The rapid rotation loads the sample through centripetal acceleration, producing a shear stress of about 60 MPa at the center, causing the sample to deform. The deformation of the sample is captured on high-speed video, which is analyzed by machine-vision software from the University of Massachusetts. The deformations are compared to finite element models to determine the constitutive constants in the creep relation. Furthermore, the non-contact method exploits stress gradients within the sample to determine the stress exponent in a single test.

  4. Trophic redundancy reduces vulnerability to extinction cascades.

    Science.gov (United States)

    Sanders, Dirk; Thébault, Elisa; Kehoe, Rachel; Frank van Veen, F J

    2018-03-06

    Current species extinction rates are at unprecedentedly high levels. While human activities can be the direct cause of some extinctions, it is becoming increasingly clear that species extinctions themselves can be the cause of further extinctions, since species affect each other through the network of ecological interactions among them. There is concern that the simplification of ecosystems, due to the loss of species and ecological interactions, increases their vulnerability to such secondary extinctions. It is predicted that more complex food webs will be less vulnerable to secondary extinctions due to greater trophic redundancy that can buffer against the effects of species loss. Here, we demonstrate in a field experiment with replicated plant-insect communities, that the probability of secondary extinctions is indeed smaller in food webs that include trophic redundancy. Harvesting one species of parasitoid wasp led to secondary extinctions of other, indirectly linked, species at the same trophic level. This effect was markedly stronger in simple communities than for the same species within a more complex food web. We show that this is due to functional redundancy in the more complex food webs and confirm this mechanism with a food web simulation model by highlighting the importance of the presence and strength of trophic links providing redundancy to those links that were lost. Our results demonstrate that biodiversity loss, leading to a reduction in redundant interactions, can increase the vulnerability of ecosystems to secondary extinctions, which, when they occur, can then lead to further simplification and run-away extinction cascades. Copyright © 2018 the Author(s). Published by PNAS.

  5. Measurement of local void fraction at elevated temperature and pressure

    International Nuclear Information System (INIS)

    Duncan, D.; Trabold, T.A.

    1993-03-01

    Significant advances have recently been made in analytical and computational methods for the prediction of local thermal-hydraulic conditions in gas/liquid two-phase flows. There is, however, a need for extensive experimental data, for the dual purposes of constitutive relation development and code qualification. There is especially true of systems involving complicated geometries and/or extreme flow conditions for which little, if any, applicable information exists in the open literature. For the tests described in the present paper, a novel electrical probe has been applied to measure the void fraction in atmospheric pressure air/water flows, and steam/water mixtures at high temperature and pressure. The data acquired in the latter experiments are compared with the results of a one-dimensional two-fluid computational analysis

  6. Temperature in subsonic and supersonic radiation fronts measured at OMEGA

    Science.gov (United States)

    Johns, Heather; Kline, John; Lanier, Nick; Perry, Ted; Fontes, Chris; Fryer, Chris; Brown, Colin; Morton, John

    2017-10-01

    Propagation of heat fronts relevant to astrophysical plasmas is challenging in the supersonic regime. Plasma Te changes affect opacity and equation of state without hydrodynamic change. In the subsonic phase density perturbations form at material interfaces as the plasma responds to radiation pressure of the front. Recent experiments at OMEGA studied this transition in aerogel foams driven by a hohlraum. In COAX, two orthogonal backlighters drive x-ray radiography and K-shell absorption spectroscopy to diagnose the subsonic shape of the front and supersonic Te profiles. Past experiments used absorption spectroscopy in chlorinated foams to measure the heat front; however, Cl dopant is not suitable for higher material temperatures at NIF. COAX has developed use of Sc and Ti dopants to diagnose Te between 60-100eV and 100-180eV. Analysis with PrismSPECT using OPLIB tabular opacity data will evaluate the platform's ability to advance radiation transport in this regime.

  7. Implantable microchip transponders for body temperature measurements in pigs

    DEFF Research Database (Denmark)

    Lohse, Louise; Uttenthal, Åse; Enøe, Claes

    thermometer. This work, however, can be quite time consuming and laborious, and further compromising the immediate well-fare of the pig, when restraining of the individual animal is necessary. Therefore, an electronic body monitoring system using implantable microchip transponders for measuring peripheral...... body temperature was tested, in order to evaluate the utility and reliability of this tool, in domestic pigs. The system is presently used and well optimized in small laboratory animals [1, 2]. We tested the microchip transponders during experimental infection of pigs with classical swine fever virus...... microchip transponder was injected deep subcutaneously by the left ear base of each individual. The transponder was before insertion programmed with ID identical to the individual pig’s ear tag number. The pigs were randomly divided into 3 groups: one group placebo-infected and two groups virus...

  8. Surface temperature measurements on superconducting cavities in superfluid helium

    International Nuclear Information System (INIS)

    Fouaidy, T.; Junquera, T.; Caruette, A.

    1991-01-01

    Two thermometry systems have been developed: a scanning thermometer system routinely used for the 1.5 GHz monocell cavity studies and a fixed thermometer array used to investigate spatial surface resistance distribution on various SC removable endplates of a cylindrical TE011mode cavity. Thermometers used in these systems are thermally insulated from the surrounding HeII bath by an epoxy housing ('epoxy'thermometers). Accurate calibration of the fixed thermometers was conducted by using different test cells and the experimental results were compared to model calculations performed with a finite element computational code. Measured thermometer efficiency and linearity are in good agreement with numerical results. Some typical temperature maps of different Nb samples obtained with the TE011 array (40 epoxy thermometers) are discussed. On the basis of numerical modelling results, a new type of thermometer with an improved efficiency has been designed. The thermal insulation against Helium II has been drastically improved by placing the sensitive part of the thermometer in a small vacuum jacket ('vacuum' thermometers). Two main goals have been reached with the first prototypes: improved efficiency by a factor of 2.5 - 3, and a bath temperature dependence of the thermal response in good agreement with the expected Kapitza conductance behaviour. Fitting experimental results with numerical modelling data, allow us to estimate the Kapitza conductance. The obtained values are in good agreement with the previous results reported by several authors using a different measurement method. The 'vacuum' thermometers are currently used on the TE011 mode cavity with Nb and NbTiN plates and the first results are presented

  9. Influence of pre-measurement thermal treatment on OSL of synthetic quartz measured at room temperature

    International Nuclear Information System (INIS)

    Kale, Y.D.; Gandhi, Y.H.

    2008-01-01

    Much effort has been made to study the influence of pre-measurement thermal treatment and ionizing radiation on quartz specimens owing to its use in a large number of applications. Optically stimulated luminescence (OSL) being a structured and sensitive phenomenon promises to correlate the responsible color center and luminescence emission. OSL studies on quartz with such conditions can reveal many significant results. The aim of the present investigation is to understand the effect of annealing temperature on OSL characteristics of synthetic quartz recorded at room temperature. At identical annealing duration and β-dose, the shape of OSL decay curve remains non-exponential; when specimens annealed at lower temperature (∼400 deg. C). The shape of decay curve changes to exponential in nature along with rise in OSL intensity when the specimen was given higher temperature of annealing (>400 deg. C). The effects of such protocol on pattern of OSL sensitivity as well as area under the OSL decay curve are also presented here. The presence of shallow traps, when OSL decay curve was recorded at room temperature seems to be responsible for the changes in OSL pattern. The influence of shallow traps is attributed to non-exponential decay of OSL recorded at room temperature

  10. A Delay Time Measurement of ULTRAS (Ultra-high Temperature Ultrasonic Response Analysis System) for a High Temperature Experiment

    International Nuclear Information System (INIS)

    Koo, Kil Mo; Kim, Sang Baik

    2010-01-01

    The temperature measurement of very high temperature core melt is of importance in a high temperature as the molten pool experiment in which gap formation between core melt and the reactor lower head, and the effect of the gap on thermal behavior are to be measured. The existing temperature measurement techniques have some problems, which the thermocouple, one of the contact methods, is restricted to under 2000 .deg. C, and the infrared thermometry, one of the non-contact methods, is unable to measure an internal temperature and very sensitive to the interference from reacted gases. In order to solve these problems, the delay time technique of ultrasonic wavelets due to high temperature has two sorts of stage. As a first stage, a delay time measurement of ULTRAS (Ultra-high Temperature Ultrasonic Response Analysis System) is suggested. As a second stage, a molten material temperature was measured up to 2300 .deg. C. Also, the optimization design of the UTS (ultrasonic temperature sensor) with persistence at the high temperature was suggested in this paper. And the utilization of the theory suggested in this paper and the efficiency of the developed system are performed by special equipment and some experiments supported by KRISS (Korea Research Institute of Standard and Science)

  11. Soil Temperature Variability in Complex Terrain measured using Distributed a Fiber-Optic Distributed Temperature Sensing

    Science.gov (United States)

    Seyfried, M. S.; Link, T. E.

    2013-12-01

    Soil temperature (Ts) exerts critical environmental controls on hydrologic and biogeochemical processes. Rates of carbon cycling, mineral weathering, infiltration and snow melt are all influenced by Ts. Although broadly reflective of the climate, Ts is sensitive to local variations in cover (vegetative, litter, snow), topography (slope, aspect, position), and soil properties (texture, water content), resulting in a spatially and temporally complex distribution of Ts across the landscape. Understanding and quantifying the processes controlled by Ts requires an understanding of that distribution. Relatively few spatially distributed field Ts data exist, partly because traditional Ts data are point measurements. A relatively new technology, fiber optic distributed temperature system (FO-DTS), has the potential to provide such data but has not been rigorously evaluated in the context of remote, long term field research. We installed FO-DTS in a small experimental watershed in the Reynolds Creek Experimental Watershed (RCEW) in the Owyhee Mountains of SW Idaho. The watershed is characterized by complex terrain and a seasonal snow cover. Our objectives are to: (i) evaluate the applicability of fiber optic DTS to remote field environments and (ii) to describe the spatial and temporal variability of soil temperature in complex terrain influenced by a variable snow cover. We installed fiber optic cable at a depth of 10 cm in contrasting snow accumulation and topographic environments and monitored temperature along 750 m with DTS. We found that the DTS can provide accurate Ts data (+/- .4°C) that resolves Ts changes of about 0.03°C at a spatial scale of 1 m with occasional calibration under conditions with an ambient temperature range of 50°C. We note that there are site-specific limitations related cable installation and destruction by local fauna. The FO-DTS provide unique insight into the spatial and temporal variability of Ts in a landscape. We found strong seasonal

  12. Raman Channel Temperature Measurement of SiC MESFET as a Function of Ambient Temperature and DC Power

    Science.gov (United States)

    Ponchak, George E.; Eldridge, Jeffrey J.; Krainsky, Isay L.

    2009-01-01

    Raman spectroscopy is used to measure the junction temperature of a Cree SiC MESFET as a function of the ambient temperature and DC power. The carrier temperature, which is approximately equal to the ambient temperature, is varied from 25 C to 450 C, and the transistor is biased with VDS=10V and IDS of 50 mA and 100 mA. It is shown that the junction temperature is approximately 52 and 100 C higher than the ambient temperature for the DC power of 500 and 1000 mW, respectively.

  13. Optical measurement system for non-contact temperature profile

    CSIR Research Space (South Africa)

    Masina, BN

    2009-07-01

    Full Text Available In principle all objects emit thermal radiation as a consequence of their temperature. The thermal radiation emitted by an object depends on its temperature, surface condition and thermal properties. A thermography camera senses the emission from...

  14. Northern Mariana Islands Marine Monitoring Team Sea Temperature Measurements

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Site specific monitoring of sea temperature is conducted using submersible temperature dataloggers at selected sites and depths around the islands of Saipan and Rota.

  15. Tack Measurements of Prepreg Tape at Variable Temperature and Humidity

    Science.gov (United States)

    Wohl, Christopher; Palmieri, Frank L.; Forghani, Alireza; Hickmott, Curtis; Bedayat, Houman; Coxon, Brian; Poursartip, Anoush; Grimsley, Brian

    2017-01-01

    NASA’s Advanced Composites Project has established the goal of achieving a 30 percent reduction in the timeline for certification of primary composite structures for application on commercial aircraft. Prepreg tack is one of several critical parameters affecting composite manufacturing by automated fiber placement (AFP). Tack plays a central role in the prevention of wrinkles and puckers that can occur during AFP, thus knowledge of tack variation arising from a myriad of manufacturing and environmental conditions is imperative for the prediction of defects during AFP. A full design of experiments was performed to experimentally characterize tack on 0.25-inch slit-tape tow IM7/8552-1 prepreg using probe tack testing. Several process parameters (contact force, contact time, retraction speed, and probe diameter) as well as environmental parameters (temperature and humidity) were varied such that the entire parameter space could be efficiently evaluated. Mid-point experimental conditions (i.e., parameters not at either extrema) were included to enable prediction of curvature in relationships and repeat measurements were performed to characterize experimental error. Collectively, these experiments enable determination of primary dependencies as well as multi-parameter relationships. Slit-tape tow samples were mounted to the bottom plate of a rheometer parallel plate fixture using a jig to prevent modification of the active area to be interrogated with the top plate, a polished stainless steel probe, during tack testing. The probe surface was slowly brought into contact with the pre-preg surface until a pre-determined normal force was achieved (2-30 newtons). After a specified dwell time (0.02-10 seconds), during which the probe substrate interaction was maintained under displacement control, the probe was retracted from the surface (0.1-50 millimeters per second). Initial results indicated a clear dependence of tack strength on several parameters, with a particularly

  16. The correlation between superparamagnetic blocking temperatures and peak temperatures obtained from ac magnetization measurements

    International Nuclear Information System (INIS)

    Madsen, Daniel Esmarch; Moerup, Steen; Hansen, Mikkel Fougt

    2008-01-01

    We study the correlation between the superparamagnetic blocking temperature T B and the peak positions T p observed in ac magnetization measurements for nanoparticles of different classes of magnetic materials. In general, T p = α+βT B . The parameters α and β are different for the in-phase (χ') and out-of-phase (χ'') components and depend on the width σ V of the log-normal volume distribution and the class of magnetic material (ferromagnetic/antiferromagnetic). Consequently, knowledge of both α and β is required if the anisotropy energy barrier KV and the attempt time τ 0 are to be reliably obtained from an analysis based solely on the peak positions

  17. Quantifying Net Synergy/Redundancy of Spontaneous Variability Regulation via Predictability and Transfer Entropy Decomposition Frameworks.

    Science.gov (United States)

    Porta, Alberto; Bari, Vlasta; De Maria, Beatrice; Takahashi, Anielle C M; Guzzetti, Stefano; Colombo, Riccardo; Catai, Aparecida M; Raimondi, Ferdinando; Faes, Luca

    2017-11-01

    Objective: Indexes assessing the balance between redundancy and synergy were hypothesized to be helpful in characterizing cardiovascular control from spontaneous beat-to-beat variations of heart period (HP), systolic arterial pressure (SAP), and respiration (R). Methods: Net redundancy/synergy indexes were derived according to predictability and transfer entropy decomposition strategies via a multivariate linear regression approach. Indexes were tested in two protocols inducing modifications of the cardiovascular regulation via baroreflex loading/unloading (i.e., head-down tilt at -25° and graded head-up tilt at 15°, 30°, 45°, 60°, 75°, and 90°, respectively). The net redundancy/synergy of SAP and R to HP and of HP and R to SAP were estimated over stationary sequences of 256 successive values. Results: We found that: 1) regardless of the target (i.e., HP or SAP) redundancy was prevalent over synergy and this prevalence was independent of type and magnitude of the baroreflex challenge; 2) the prevalence of redundancy disappeared when decoupling inputs from output via a surrogate approach; 3) net redundancy was under autonomic control given that it varied in proportion to the vagal withdrawal during graded head-up tilt; and 4) conclusions held regardless of the decomposition strategy. Conclusion: Net redundancy indexes can monitor changes of cardiovascular control from a perspective completely different from that provided by more traditional univariate and multivariate methods. Significance: Net redundancy measures might provide a practical tool to quantify the reservoir of effective cardiovascular regulatory mechanisms sharing causal influences over a target variable. Objective: Indexes assessing the balance between redundancy and synergy were hypothesized to be helpful in characterizing cardiovascular control from spontaneous beat-to-beat variations of heart period (HP), systolic arterial pressure (SAP), and respiration (R). Methods: Net redundancy

  18. Does functional redundancy stabilize fish communities?

    DEFF Research Database (Denmark)

    Rice, Jake; Daan, Niels; Gislason, Henrik

    2012-01-01

    Functional redundancy is a community property thought to contribute to ecosystem resilience. It is argued that trophic (or other) functional groups with more species have more linkages and opportunities to buffer variation in abundance of individual species. We explored this concept with a 30‐year...... time‐series of data on 83 species sampled in the International Bottom Trawl Survey. Our results were consistent with the hypothesis that functional redundancy leads to more stable (and by inference more resilient) communities. Over the time‐series trophic groups (assigned by diet, size (Lmax) group......, or both factors) with more species had lower coefficients of variation (CVs) in abundance and biomass than did trophic groups with fewer species. These findings are also consistent with Bernoulli’s Law of Large Numbers, a rule that does not require complex ecological and evolutionary processes to produce...

  19. Preliminary study of temperature measurement techniques for Stirling engine reciprocating seals

    Science.gov (United States)

    Wilcock, D. F.; Hoogenboom, L.; Meinders, M.; Winer, W. O.

    1981-01-01

    Methods of determining the contact surface temperature in reciprocating seals are investigated. Direct infrared measurement of surface temperatures of a rod exiting a loaded cap seal or simulated seal are compared with surface thermocouple measurements. Significant cooling of the surface requires several milliseconds so that exit temperatures may be considered representative of internal contact temperatures.

  20. Dynamically redundant particle components in mixtures

    International Nuclear Information System (INIS)

    Lukacs, B.; Martinas, K.

    1984-10-01

    Examples are shown for cases in which the number of different kinds of particles in a system is not necessarily equal to the number of particle degrees of freedom in thermodynamical sense, and at the same time, the observed dynamics of the evolution of the system does not indicate a definite number of degrees of freedeom. The possibility for introducing dynamically redundant particles is discussed. (author)

  1. Parameter identifiability and redundancy: theoretical considerations.

    Directory of Open Access Journals (Sweden)

    Mark P Little

    Full Text Available BACKGROUND: Models for complex biological systems may involve a large number of parameters. It may well be that some of these parameters cannot be derived from observed data via regression techniques. Such parameters are said to be unidentifiable, the remaining parameters being identifiable. Closely related to this idea is that of redundancy, that a set of parameters can be expressed in terms of some smaller set. Before data is analysed it is critical to determine which model parameters are identifiable or redundant to avoid ill-defined and poorly convergent regression. METHODOLOGY/PRINCIPAL FINDINGS: In this paper we outline general considerations on parameter identifiability, and introduce the notion of weak local identifiability and gradient weak local identifiability. These are based on local properties of the likelihood, in particular the rank of the Hessian matrix. We relate these to the notions of parameter identifiability and redundancy previously introduced by Rothenberg (Econometrica 39 (1971 577-591 and Catchpole and Morgan (Biometrika 84 (1997 187-196. Within the widely used exponential family, parameter irredundancy, local identifiability, gradient weak local identifiability and weak local identifiability are shown to be largely equivalent. We consider applications to a recently developed class of cancer models of Little and Wright (Math Biosciences 183 (2003 111-134 and Little et al. (J Theoret Biol 254 (2008 229-238 that generalize a large number of other recently used quasi-biological cancer models. CONCLUSIONS/SIGNIFICANCE: We have shown that the previously developed concepts of parameter local identifiability and redundancy are closely related to the apparently weaker properties of weak local identifiability and gradient weak local identifiability--within the widely used exponential family these concepts largely coincide.

  2. Redundant sensor validation by using fuzzy logic

    International Nuclear Information System (INIS)

    Holbert, K.E.; Heger, A.S.; Alang-Rashid, N.K.

    1994-01-01

    This research is motivated by the need to relax the strict boundary of numeric-based signal validation. To this end, the use of fuzzy logic for redundant sensor validation is introduced. Since signal validation employs both numbers and qualitative statements, fuzzy logic provides a pathway for transforming human abstractions into the numerical domain and thus coupling both sources of information. With this transformation, linguistically expressed analysis principles can be coded into a classification rule-base for signal failure detection and identification

  3. Redundancy Determination of HVDC MMC Modules

    Directory of Open Access Journals (Sweden)

    Chanki Kim

    2015-08-01

    Full Text Available An availability and a reliability prediction has been made for a high-voltage direct-current (HVDC module of VSC (Voltage Source Converter containing DC/DC converter, gate driver, capacitor and insulated gate bipolar transistors (IGBT. This prediction was made using published failure rates for the electronic equipment. The purpose of this prediction is to determinate the additional module redundancy of VSC and the used method is “binomial failure method”.

  4. Effect and control on temperature measurement accuracy of the fiber- optic colorimeter by emissivity of different temperatures

    Science.gov (United States)

    Liu, Yu-fang; Han, Xin; Shi, De-heng

    2008-03-01

    Based on the Kirchhoff's Law, a practical dual-wavelength fiber-optic colorimeter, with the optimal work wavelength centered at 2.1 μm and 2.3 μm is presented. The effect of the emissivity on the precision of the measured temperature has been explored under various circumstances (i.e. temperature, wavelength) and for different materials. In addition, by fitting several typical material emissivity-temperature dependencies curves, the influence of the irradiation (radiant flux originating from the surroundings) and the surface reflected radiation on the temperature accuracy is studied. The results show that the calibration of the measured temperature for reflected radiant energy is necessary especially in low target temperature or low target emissivity, and the temperature accuracy is suitable for requirements in the range of 400-1200K.

  5. Comparison of three methods of temperature measurement in hypothermic, euthermic, and hyperthermic dogs.

    Science.gov (United States)

    Greer, Rebecca J; Cohn, Leah A; Dodam, John R; Wagner-Mann, Colette C; Mann, F A

    2007-06-15

    To assess the reliability and accuracy of a predictive rectal thermometer, an infrared auricular thermometer designed for veterinary use, and a subcutaneous temperature-sensing microchip for measurement of core body temperature over various temperature conditions in dogs. Prospective study. 8 purpose-bred dogs. A minimum of 7 days prior to study commencement, a subcutaneous temperature-sensing microchip was implanted in 1 of 3 locations (interscapular, lateral aspect of shoulder, or sacral region) in each dog. For comparison with temperatures measured via rectal thermometer, infrared auricular thermometer, and microchip, core body temperature was measured via a thermistor-tipped pulmonary artery (TTPA) catheter. Hypothermia was induced during anesthesia at the time of TTPA catheter placement; on 3 occasions after placement of the catheter, hyperthermia was induced via administration of a low dose of endotoxin. Near-simultaneous duplicate temperature measurements were recorded from the TTPA catheter, the rectal thermometer, auricular thermometer, and subcutaneous microchips during hypothermia, euthermia, and hyperthermia. Reliability (variability) of temperature measurement for each device and agreement between each device measurement and core body temperature were assessed. Variability between duplicate near-simultaneous temperature measurements was greatest for the auricular thermometer and least for the TTPA catheter. Measurements obtained by use of the rectal thermometer were in closest agreement with core body temperature; for all other devices, temperature readings typically underestimated core body temperature. Among the 3 methods of temperature measurement, rectal thermometry provided the most accurate estimation of core body temperature in dogs.

  6. Measurements of temperature of the tungsten hexa-ethoxide pyrolysis flame using IR camera

    CSIR Research Space (South Africa)

    Mudau, AE

    2010-09-01

    Full Text Available In laser pyrolysis, temperature measurement and control plays a vital role during the development of nanoparticles. Authors present the results of temperature measurements using infrared camera on a tungsten hexa-ethoxide pyrolysis flame used...

  7. The Building America Indoor Temperature and Humidity Measurement Protocol

    Energy Technology Data Exchange (ETDEWEB)

    Metzger, C. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Norton, Paul [Norton Energy Research & Development, Boulder, CO (United States)

    2014-02-01

    When modeling homes using simulation tools, the heating and cooling set points can have a significant impact on home energy use. Every four years, the Energy Information Administration (EIA) Residential Energy Consumption Survey (RECS) asks homeowners about their heating and cooling set points. Unfortunately, no temperature data is measured, and most of the time, the homeowner may be guessing at this number. Even one degree Fahrenheit difference in heating set point can make a 5% difference in heating energy use! So, the survey-based RECS data cannot be used as the definitive reference for the set point for the "average occupant" in simulations. The purpose of this document is to develop a protocol for collecting consistent data for heating/cooling set points and relative humidity so that an average set point can be determined for asset energy models in residential buildings. This document covers the decision making process for researchers to determine how many sensors should be placed in each home, where to put those sensors, and what kind of asset data should be taken while they are in the home. The authors attempted to design the protocols to maximize the value of this study and minimize the resources required to achieve that value.

  8. Building America Indoor Temperature and Humidity Measurement Protocol

    Energy Technology Data Exchange (ETDEWEB)

    Engebrecht-Metzger, Cheryn [National Renewable Energy Lab. (NREL), Golden, CO (United States); Norton, Paul [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2014-02-01

    When modeling homes using simulation tools, the heating and cooling set points can have a significant impact on home energy use. Every 4 years the Energy Information Administration (EIA) Residential Energy Consumption Survey (RECS) asks homeowners about their heating and cooling set points. Unfortunately, no temperature data is measured, and most of the time, the homeowner may be guessing at this number. Even one degree Fahrenheit difference in heating set point can make a 5% difference in heating energy use! So, the survey-based RECS data cannot be used as the definitive reference for the set point for the 'average occupant' in simulations. The purpose of this document is to develop a protocol for collecting consistent data for heating/cooling set points and relative humidity so that an average set point can be determined for asset energy models in residential buildings. This document covers the decision making process for researchers to determine how many sensors should be placed in each home, where to put those sensors, and what kind of asset data should be taken while they are in the home. The authors attempted to design the protocols to maximize the value of this study and minimize the resources required to achieve that value.

  9. Experiment to measure oxygen opacity at high density and temperature

    Science.gov (United States)

    Keiter, Paul; Butler, Hannah; Trantham, Matt; Mussack, Katie; Colgan, James; Fontes, Chris; Guzik, Joyce; Kilcrease, David; Perry, Ted; Orban, Chris; Ducret, Jean-Eric; La Pennec, Maelle; Turck-Chieze, Sylvaine; Mancini, Roberto; Heeter, Robert

    2017-10-01

    In recent years, there has been a debate over the abundances of heavy elements (Z >2) in the solar interior. Recent solar atmosphere models [Asplund 2009] find a significantly lower abundance for C, N, and O compared to models used roughly a decade ago. Recent opacity measurements of iron disagree with opacity model predictions [Bailey et al., 2015]. Repeated scrutiny of the experiment and data has not produced a conclusive reason for the discrepancy. New models have been implemented in the ATOMIC opacity code for low-Z elements [Colgan, 2013, Armstrong 2014], however no data currently exists to test the low-Z material models in the regime relevant to the solar convection zone. We present an experimental design using the opacity platform developed at the National Ignition Facility to study the oxygen opacity at densities and temperatures near the solar convection zone conditions. This work is funded by the U.S. DOE, through the NNSA-DS and SC-OFES Joint Program in HEDLP, Grant Number DE-NA0002956, and the NLUF Program, Grant Number DE-NA0002719, and through the LLE, University of Rochester by the NNSA/OICF under No. DE-NA0001944.

  10. Nonlinear Redundancy Analysis. Research Report 88-1.

    Science.gov (United States)

    van der Burg, Eeke; de Leeuw, Jan

    A non-linear version of redundancy analysis is introduced. The technique is called REDUNDALS. It is implemented within the computer program for canonical correlation analysis called CANALS. The REDUNDALS algorithm is of an alternating least square (ALS) type. The technique is defined as minimization of a squared distance between criterion…

  11. Measured Performance of a Low Temperature Air Source Heat Pump

    Energy Technology Data Exchange (ETDEWEB)

    R.K. Johnson

    2013-09-01

    A 4-ton Low Temperature Heat Pump (LTHP) manufactured by Hallowell International was installed in a residence near New Haven, Connecticut and monitored over two winters of operation. After attending to some significant service issues, the heat pump operated as designed. This report should be considered a review of the dual compressor “boosted heat pump” technology. The Low Temperature Heat Pump system operates with four increasing levels of capacity (heat output) as the outdoor temperature drops.

  12. Microchip-based body temperature measurements in pigs

    DEFF Research Database (Denmark)

    Nielsen, Jens; Lohse, Louise

    In the present study, we tested whether an electronic identification and body temperature monitorring technology presently applied in small experimental animals could be transferred for use in pigs....

  13. Comparison between core temperatures measured telemetrically using the CorTemp® ingestible temperature sensor and rectal temperature in healthy Labrador retrievers.

    Science.gov (United States)

    Osinchuk, Stephanie; Taylor, Susan M; Shmon, Cindy L; Pharr, John; Campbell, John

    2014-10-01

    This study evaluated the CorTemp(®) ingestible telemetric core body temperature sensor in dogs, to establish the relationship between rectal temperature and telemetrically measured core body temperature at rest and during exercise, and to examine the effect of sensor location in the gastrointestinal (GI) tract on measured core temperature. CorTemp(®) sensors were administered orally to fasted Labrador retriever dogs and radiographs were taken to document sensor location. Core and rectal temperatures were monitored throughout the day in 6 resting dogs and during a 10-minute strenuous retrieving exercise in 6 dogs. Time required for the sensor to leave the stomach (120 to 610 min) was variable. Measured core temperature was consistently higher than rectal temperature across all GI locations but temperature differences based on GI location were not significant (P = 0.5218). Resting dogs had a core temperature that was on average 0.4°C above their rectal temperature with 95% limits of agreement (LoA) between 1.2°C and -0.5°C. Core temperature in exercising dogs was on average 0.3°C higher than their concurrent rectal temperature, with LoA of +1.6°C and -1.1°C.

  14. Measurement of peak temperature along an optical fiber

    International Nuclear Information System (INIS)

    Fox, R.J.

    1983-01-01

    A multimode silica-clad optical fiber with a liquid silicone core was used as a distributed-line peak-temperature sensor over a temperature range from ambient to 190 0 C. The maximum error was 2 0 C and was essentially independent of the length or position of the hot zone

  15. Equilibrium adsorption data from temperature-programmed desorption measurements

    NARCIS (Netherlands)

    Foeth, F.; Mugge, J.M.; van der Vaart, R.; van der Vaart, Rick; Bosch, H.; Reith, T.

    1996-01-01

    This work describes a novel method that enables the calculation of a series of adsorption isotherms basically from a single Temperature-Programmed Desorption (TPD) experiment. The basic idea is to saturate an adsorbent packed in a fixed bed at a certain feed concentration and temperature and to

  16. Three Mile Island ambient-air-temperature sensor measurements

    International Nuclear Information System (INIS)

    Fryer, M.O.

    1983-01-01

    Data from the ambient-air-temperature sensors in Three Mile Island-Unit 2 (TMI-2) reactor containment building are analyzed. The data were for the period of the hydrogen burn that was part of the TMI-2 accident. From the temperature data, limits are placed on the duration of the hydrogen burn

  17. Temperature measurements in a wall stabilized steady flame using CARS

    KAUST Repository

    Sesha Giri, Krishna; Lacoste, Deanna; Damazo, Jason; Kwon, Eddie; Roberts, William L.

    2017-01-01

    -Stokes Raman Scattering (CARS) thermometry as close as 275 μm to a convex wall cooled with water has been carried out. The standard deviation of mean temperatures is observed to be ~6.5% for high temperatures (>2000K) and ~14% in the lower range (<500K

  18. How redundant are redundant color adjectives? An efficiency-based analysis of color overspecification

    Directory of Open Access Journals (Sweden)

    Paula eRubio-Fernández

    2016-02-01

    Full Text Available Color adjectives tend to be used redundantly in referential communication. I propose that redundant color adjectives are often intended to exploit a color contrast in the visual context and hence facilitate object identification, despite not being necessary to establish unique reference. Two language-production experiments investigated two types of factors that may affect the use of redundant color adjectives: factors related to the efficiency of color in the visual context and factors related to the semantic category of the noun. The results of Experiment 1 confirmed that people produce redundant color adjectives when color may facilitate object recognition; e.g., they do so more often in polychrome displays than in monochrome displays, and more often in English (pre-nominal position than in Spanish (post-nominal position. Redundant color adjectives are also used when color is a central property of the object category; e.g., people referred to the color of clothes more often than to the color of geometrical figures (Experiment 1, and they overspecified atypical colors more often than variable and stereotypical colors (Experiment 2. These results are relevant for pragmatic models of referential communication based on Gricean pragmatics and informativeness. An alternative analysis is proposed, which focuses on the efficiency and pertinence of color in a given referential situation.

  19. A new model for the redundancy allocation problem with component mixing and mixed redundancy strategy

    International Nuclear Information System (INIS)

    Gholinezhad, Hadi; Zeinal Hamadani, Ali

    2017-01-01

    This paper develops a new model for redundancy allocation problem. In this paper, like many recent papers, the choice of the redundancy strategy is considered as a decision variable. But, in our model each subsystem can exploit both active and cold-standby strategies simultaneously. Moreover, the model allows for component mixing such that components of different types may be used in each subsystem. The problem, therefore, boils down to determining the types of components, redundancy levels, and number of active and cold-standby units of each type for each subsystem to maximize system reliability by considering such constraints as available budget, weight, and space. Since RAP belongs to the NP-hard class of optimization problems, a genetic algorithm (GA) is developed for solving the problem. Finally, the performance of the proposed algorithm is evaluated by applying it to a well-known test problem from the literature with relatively satisfactory results. - Highlights: • A new model for the redundancy allocation problem in series–parallel systems is proposed. • The redundancy strategy of each subsystem is considered as a decision variable and can be active, cold-standby or mixed. • Component mixing is allowed, in other words components of any subsystem can be non-identical. • A genetic algorithm is developed for solving the problem. • Computational experiments demonstrate that the new model leads to interesting results.

  20. Analysis of acoustic reflectors for SAW temperature sensor and wireless measurement of temperature

    International Nuclear Information System (INIS)

    Kim, Ki Bok; Kim, Seong Hoon; Jeong, Jae Kee; Shin, Beom Soo

    2013-01-01

    In this study, a wireless and non power SAW (surface acoustic wave) temperature sensor was developed. The single inter digital transducer (IDT) of SAW temperature sensor of which resonance frequency is 434 MHz was fabricated on 128.deg rot-X LiNbO 3 piezoelectric substrate by semiconductor processing technology. To find optimal acoustic reflector for SAW temperature sensor, various kinds of acoustic reflectors were fabricated and their reflection characteristics were analyzed. The IDT type acoustic reflector showed better reflection characteristic than other reflectors. The wireless temperature sensing system consisting of SAW temperature sensor with dipole antenna and a microprocessor based control circuit with dipole antenna for transmitting signal to activate the SAW temperature sensor and receiving the signal from SAW temperature sensor was developed. The result with wireless SAW temperature sensing system showed that the frequency of SAW temperature sensor was linearly decreased with the increase of temperature in the range of 40 to 80.deg.C and the developed wireless SAW temperature sensing system showed the excellent performance with the coefficient of determination of 0.99

  1. Diode temperature sensor array for measuring and controlling micro scale surface temperature

    International Nuclear Information System (INIS)

    Han, Il Young; Kim, Sung Jin

    2004-01-01

    The needs of micro scale thermal detecting technique are increasing in biology and chemical industry. For example, thermal finger print, Micro PCR(Polymer Chain Reaction), TAS and so on. To satisfy these needs, we developed a DTSA(Diode Temperature Sensor Array) for detecting and controlling the temperature on small surface. The DTSA is fabricated by using VLSI technique. It consists of 32 array of diodes(1,024 diodes) for temperature detection and 8 heaters for temperature control on a 8mm surface area. The working principle of temperature detection is that the forward voltage drop across a silicon diode is approximately proportional to the inverse of the absolute temperature of diode. And eight heaters (1K) made of poly-silicon are added onto a silicon wafer and controlled individually to maintain a uniform temperature distribution across the DTSA. Flip chip packaging used for easy connection of the DTSA. The circuitry for scanning and controlling DTSA are also developed

  2. Noncontacting acoustics-based temperature measurement techniques in rapid thermal processing

    Science.gov (United States)

    Lee, Yong J.; Chou, Ching-Hua; Khuri-Yakub, Butrus T.; Saraswat, Krishna C.

    1991-04-01

    Temperature measurement of silicon wafers based on the temperature dependence of acoustic waves is studied. The change in the temperature-dependent dispersion relations of the plate modes through the wafer can be exploited to provide a viable temperature monitoring scheme with advantages over both thermocouples and pyrometers. Velocity measurements of acoustic waves through a thin layer of ambient directly above the wafer provides the temperature of the wafer-ambient interface. 1.

  3. Critical current measurements of high-temperature superconducting short samples at a wide range of temperatures and magnetic fields

    Science.gov (United States)

    Ma, Hongjun; Liu, Huajun; Liu, Fang; Zhang, Huahui; Ci, Lu; Shi, Yi; Lei, Lei

    2018-01-01

    High-Temperature Superconductors (HTS) are potential materials for high-field magnets, low-loss transmission cables, and Superconducting Magnetic Energy Storage (SMES) due to their high upper critical magnetic field (Hc2) and critical temperature (Tc). The critical current (Ic) of HTS, which is one of the most important parameters for superconductor application, depends strongly on the magnetic fields and temperatures. A new Ic measurement system that can carry out accurate Ic measurement for HTS short samples with various temperatures (4.2-80 K), magnetic fields (0-14 T), and angles of the magnetic field (0°-90°) has been developed. The Ic measurement system mainly consists of a measurement holder, temperature-control system, background magnet, test cryostat, data acquisition system, and DC power supply. The accuracy of temperature control is better than ±0.1 K over the 20-80 K range and ±0.05 K when measured below 20 K. The maximum current is over 1000 A with a measurement uncertainty of 1%. The system had been successfully used for YBa2Cu3O7-x(YBCO) tapes Ic determination with different temperatures and magnetic fields.

  4. Critical current measurements of high-temperature superconducting short samples at a wide range of temperatures and magnetic fields.

    Science.gov (United States)

    Ma, Hongjun; Liu, Huajun; Liu, Fang; Zhang, Huahui; Ci, Lu; Shi, Yi; Lei, Lei

    2018-01-01

    High-Temperature Superconductors (HTS) are potential materials for high-field magnets, low-loss transmission cables, and Superconducting Magnetic Energy Storage (SMES) due to their high upper critical magnetic field (H c2 ) and critical temperature (T c ). The critical current (I c ) of HTS, which is one of the most important parameters for superconductor application, depends strongly on the magnetic fields and temperatures. A new I c measurement system that can carry out accurate I c measurement for HTS short samples with various temperatures (4.2-80 K), magnetic fields (0-14 T), and angles of the magnetic field (0°-90°) has been developed. The I c measurement system mainly consists of a measurement holder, temperature-control system, background magnet, test cryostat, data acquisition system, and DC power supply. The accuracy of temperature control is better than ±0.1 K over the 20-80 K range and ±0.05 K when measured below 20 K. The maximum current is over 1000 A with a measurement uncertainty of 1%. The system had been successfully used for YBa 2 Cu 3 O 7-x (YBCO) tapes I c determination with different temperatures and magnetic fields.

  5. Redundant Sensors for Mobile Robot Navigation

    Science.gov (United States)

    1985-09-01

    represent a probability that the area is empty, while positive numbers mcan it’s probably occupied. Zero reprtsents the unknown. The basic idea is that...room to give it absolute positioning information. This works by using two infrared emitters and detectors on the robot. Measurements of anglcs are made...meters (T in Kelvin) 273 sec Distances returned when assuming 80 degrees Farenheit , but where. actual temperature is 60 degrees, will be seven inches

  6. Redundancy of Redundancy in Justifications of Verdicts of Polish The Constitutional Tribuna

    Directory of Open Access Journals (Sweden)

    Jan Winczorek

    2016-09-01

    Full Text Available The results of an empirical study of 150 justifications of verdicts of the Polish Constitutional Tribunal (CT are discussed. CT justifies its decisions mostly on authoritative references to previous decisions and other doxa- type arguments. It thus does not convince the audience of a decision's validity, but rather documents it. Further, the methodology changes depending on features of the case. The results are analysed using a conceptual    framework    of sociological systems theory. It is shown that CT's justification methodology ignores the redundancy (excess of references and dependencies of the legal system, finding redundancy redundant. This is a risky strategy of decision- making, enabling political influence.

  7. Language as an information system: redundancy and optimization

    Directory of Open Access Journals (Sweden)

    Irina Mikhaylovna Nekipelova

    2015-11-01

    Full Text Available The paper is devoted to research of the language system as an information system. The distinguishing feature of any natural living language system is redundant of elements of its structure. Redundancy, broken terms of universality peculiar to artificial information systems, makes language mobile in time and in space. It should be marked out informational redundancy of two types: language redundancy, when information overlay of language units within the system occurs and speech redundancy when condense of information into syntagmatic level occurs. Language redundancy is potential and speech redundancy is actual. In general, it should be noted that the language redundancy is necessary for language: complicating the relationships between language units, language redundancy creates in language situation of choice, leading to a disorder of language system, increasing of entropy and, as a result, the appearing of the information that can be accepted or cannot be by language system. Language redundancy is one of the reasons for growth of information in language. In addition, the information redundancy in language is one of the factors of language system development.

  8. The approximate determination of the critical temperature of a liquid by measuring surface tension versus the temperature

    International Nuclear Information System (INIS)

    Maroto, J A; Nieves, F J de las; Quesada-Perez, M

    2004-01-01

    A classical experience in a physics student laboratory is to determine the surface tension of a liquid versus the temperature and to check the linear appearance of the obtained graph. In this work we show a simple method to estimate the critical temperature of three liquids by using experimental data of surface tension at different temperatures. By a logarithm fitting between surface tension and temperature, the critical temperature can be determined and compared with data from the literature. For two liquids (butanol and nitrobenzene) the comparison is acceptable but the differences are too high for the third liquid (water). By discussing the results it seems to be clear that the difference between the critical temperature of the liquid and the maximum temperature of the surface tension measurements is the determining factor in obtaining acceptable results. From this study it is possible to obtain more information on the liquid characteristics from surface tension measurements that are currently carried out in a student laboratory. Besides, in this paper it is shown how to select the most suitable liquids which provide both acceptable values for the critical temperature and measurements of the surface tension at moderate temperatures. The complementary use of numerical methods permits us to offer a complete experience for the students with a simple laboratory experiment which we recommend for physics students in advanced university courses

  9. Wall temperature measurements using a thermal imaging camera with temperature-dependent emissivity corrections

    International Nuclear Information System (INIS)

    McDaid, Chloe; Zhang, Yang

    2011-01-01

    A methodology is presented whereby the relationship between temperature and emissivity for fused quartz has been used to correct the temperature values of a quartz impingement plate detected by an SC3000 thermal imaging camera. The methodology uses an iterative method using the initial temperature (obtained by assuming a constant emissivity) to find the emissivity values which are then put into the thermal imaging software and used to find the subsequent temperatures, which are used to find the emissivities, and so on until converged. This method is used for a quartz impingement plate that has been heated under various flame conditions, and the results are compared. Radiation losses from the plate are also calculated, and it is shown that even a slight change in temperature greatly affects the radiation loss. It is a general methodology that can be used for any wall material whose emissivity is a function of temperature

  10. Body temperature measurement in mice during acute illness: implantable temperature transponder versus surface infrared thermometry.

    Science.gov (United States)

    Mei, Jie; Riedel, Nico; Grittner, Ulrike; Endres, Matthias; Banneke, Stefanie; Emmrich, Julius Valentin

    2018-02-23

    Body temperature is a valuable parameter in determining the wellbeing of laboratory animals. However, using body temperature to refine humane endpoints during acute illness generally lacks comprehensiveness and exposes to inter-observer bias. Here we compared two methods to assess body temperature in mice, namely implanted radio frequency identification (RFID) temperature transponders (method 1) to non-contact infrared thermometry (method 2) in 435 mice for up to 7 days during normothermia and lipopolysaccharide (LPS) endotoxin-induced hypothermia. There was excellent agreement between core and surface temperature as determined by method 1 and 2, respectively, whereas the intra- and inter-subject variation was higher for method 2. Nevertheless, using machine learning algorithms to determine temperature-based endpoints both methods had excellent accuracy in predicting death as an outcome event. Therefore, less expensive and cumbersome non-contact infrared thermometry can serve as a reliable alternative for implantable transponder-based systems for hypothermic responses, although requiring standardization between experimenters.

  11. Design and realization of temperature measurement system based on optical fiber temperature sensor for wireless power transfer

    Science.gov (United States)

    Chen, Xi; Zeng, Shuang; Liu, Xiulan; Jin, Yuan; Li, Xianglong; Wang, Xiaochen

    2018-02-01

    The electric vehicles (EV) have become accepted by increasing numbers of people for the environmental-friendly advantages. A novel way to charge the electric vehicles is through wireless power transfer (WPT). The wireless power transfer is a high power transfer system. The high currents flowing through the transmitter and receiver coils increasing temperature affects the safety of person and charging equipment. As a result, temperature measurement for wireless power transfer is needed. In this paper, a temperature measurement system based on optical fiber temperature sensors for electric vehicle wireless power transfer is proposed. Initially, the thermal characteristics of the wireless power transfer system are studied and the advantages of optical fiber sensors are analyzed. Then the temperature measurement system based on optical fiber temperature sensor is designed. The system consists of optical subsystem, data acquisition subsystem and data processing subsystem. Finally, the system is tested and the experiment result shows that the system can realize 1°C precision and can acquire real-time temperature distribution of the coils, which can meet the requirement of the temperature measuring for wireless power transfer.

  12. Measurements of effective noise temperature in fused silica fiber violin modes

    Energy Technology Data Exchange (ETDEWEB)

    Bilenko, I.A.; Lourie, S.L

    2002-11-25

    The results of measurements of the effective noise temperature in fused silica fiber violin modes are presented. In these measurements the fibers were stressed and value of the effective noise temperature was obtained by direct observation of oscillations in the fundamental violin modes of several samples. Measured values indicate that effective noise temperature does not exceed the room temperature significantly. This result is important for the design of the advanced gravitational wave antennae.

  13. Conception and preliminary evaluation of an optical fibre sensor for simultaneous measurement of pressure and temperature

    International Nuclear Information System (INIS)

    Bremer, K; Moss, B; Leen, G; Mueller, I; Lewis, E; Lochmann, S

    2009-01-01

    This paper presents a novel concept of simultaneously measuring pressure and temperature using a silica optical fibre extrinsic Fabry-Perot interferometric (EFPI) pressure sensor incorporating a fibre Bragg grating (FBG), which is constructed entirely from fused-silica. The novel device is used to simultaneously provide accurate pressure and temperature readings at the point of measurement. Furthermore, the FBG temperature measurement is used to eliminate the temperature cross-sensitivity of the EFPI pressure sensor.

  14. In-motion, non-contact rail temperature measurement sensor.

    Science.gov (United States)

    2012-12-01

    Preventing track buckling incidents (Figure 1) is important to the railroad industry. Track materials, rail steel, for example, experience thermal expansion, which refers to the increase in a materials volume as its temperature rises. Thermal expa...

  15. Transformer Temperature Measurment Using Optical Fiber Based Microbend Sensor

    Directory of Open Access Journals (Sweden)

    Deepika YADAV

    2007-10-01

    Full Text Available Breakdown of transformers proves to be very expensive and inconvenient because it takes a lot of time for their replacement. During breakdown the industry also incurs heavy losses because of stoppage in production line. A system for monitoring the temperature of transformers is required. Existing sensors cannot be used for monitoring the temperature of transformers because they are sensitive to electrical signals and can cause sparking which can trigger fire since there is oil in transformers cooling coils. Optical fibers are electrically inert so this system will prove to be ideal for this application. Results of investigations carried out by simulating a configuration of Optical Fiber Temperature Sensor for transformers based on microbending using Matlab as a simulation tool to evaluate the effectiveness of this sensor have been communicated through this manuscript. The results are in the form of graphs of intensity modulation vs. the temperature.

  16. In situ gas temperature measurements by UV-absorption spectroscopy

    DEFF Research Database (Denmark)

    Fateev, Alexander; Clausen, Sønnik

    2009-01-01

    The absorption spectrum of the NO A(2)Sigma(+) uniform and stable gas temperatures over a 0.533 m path....... The accuracy of both methods is discussed. Validation of the classical Lambert-Beer law has been demonstrated at NO concentrations up to 500 ppm and gas temperatures up to 1,500 degrees C over an optical absorption path length of 0.533 m....

  17. Temperature control and measurement with tunable femtosecond optical tweezers

    Science.gov (United States)

    Mondal, Dipankar; Goswami, Debabrata

    2016-09-01

    We present the effects of wavelength dependent temperature rise in a femtosecond optical tweezers. Our experiments involve the femtosecond trapping laser tunable from 740-820 nm at low power 25 mW to cause heating in the trapped volume within a homogeneous solution of sub micro-molar concentration of IR dye. The 780 nm high repetition rate laser acts as a resonant excitation source which helps to create the local heating effortlessly within the trapping volume. We have used both position autocorrelation and equipartion theorem to evaluate temperature at different wavelength having different absorption coefficient. Fixing the pulse width in the temporal domain gives constant bandwidth at spatial domain, which makes our system behave as a tunable temperature rise device with high precision. This observation leads us to calculate temperature as well as viscosity within the vicinity of the trapping zone. A mutual energy transfer occurs between the trapped bead and solvents that leads to transfer the thermal energy of solvents into the kinetic energy of the trap bead and vice-versa. Thus hot solvated molecules resulting from resonant and near resonant excitation of trapping wavelength can continuously dissipate heat to the trapped bead which will be reflected on frequency spectrum of Brownian noise exhibited by the bead. Temperature rise near the trapping zone can significantly change the viscosity of the medium. We observe temperature rise profile according to its Gaussian shaped absorption spectrum with different wavelength.

  18. Variability in Measured Space Temperatures in 60 Homes

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, D.; Lay, K.

    2013-03-01

    This report discusses the observed variability in indoor space temperature in a set of 60 homes located in Florida, New York, Oregon, and Washington. Temperature data were collected at 15-minute intervals for an entire year, including living room, master bedroom, and outdoor air temperature (Arena, et. al). The data were examined to establish the average living room temperature for the set of homes for the heating and cooling seasons, the variability of living room temperature depending on climate, and the variability of indoor space temperature within the homes. The accuracy of software-based energy analysis depends on the accuracy of input values. Thermostat set point is one of the most influential inputs for building energy simulation. Several industry standards exist that recommend differing default thermostat settings for heating and cooling seasons. These standards were compared to the values calculated for this analysis. The data examined for this report show that there is a definite difference between the climates and that the data do not agree well with any particular standard.

  19. Spectral Collection of Polyethylene Pellets at nearly Cryogenic Temperature to Improve Selectivity of Raman Measurement

    International Nuclear Information System (INIS)

    Kim, Saetbyeol; Lee, Sanguk; Hwang, Jinyoung; Chung, Hoeil

    2010-01-01

    Raman spectroscopy has been extensively used for analysis of diverse polymer samples. Normally, Raman spectral collection of samples is routinely performed at room temperature for convenience. However, the feasibility of improving spectral selectivity and the resulting quantitative accuracy, when samples are measured at nearly cryogenic temperature, has not been investigated. For this purpose, we attempted to measure the density of polyethylene (PE) pellets at cryogenic temperatures and the resulting accuracies were compared with that from room temperature measurement. Initially, each of 25 PE sample was allowed to cool down to cryogenic temperature and the corresponding Raman spectra were continuously collected while the temperature of sample increased. When the temperature of sample was at cryogenic temperature, the resulting band widths were narrower compared to those at room temperature, thereby improving the accuracy of density measurement. In overall, the proposed Raman scheme is simple and efficient; therefore, it could be further applied for analysis of other polymers.

  20. Tomographical properties of uniformly redundant arrays

    International Nuclear Information System (INIS)

    Cannon, T.M.; Fenimore, E.E.

    1978-01-01

    Recent work in coded aperture imaging has shown that the uniformly redundant array (URA) can image distant planar radioactive sources with no artifacts. The performance of two URA apertures when used in a close-up tomographic imaging system is investigated. It is shown that a URA based on m sequences is superior to one based on quadratic residues. The m sequence array not only produces less obnoxious artifacts in tomographic imaging, but is also more resilient to some described detrimental effects of close-up imaging. It is shown that in spite of these close-up effects, tomographic depth resolution increases as the source is moved closer to the detector

  1. Flat H Redundant Frangible Joint Development

    Science.gov (United States)

    Brown, Chris

    2016-01-01

    Orion and Commercial Crew Program (CCP) Partners have chosen to use frangible joints for certain separation events. The joints currently available are zero failure tolerant and will be used in mission safety applications. The goal is to further develop a NASA designed redundant frangible joint that will lower flight risk and increase reliability. FY16 testing revealed a successful design in subscale straight test specimens that gained efficiency and supports Orion load requirements. Approach / Innovation A design constraint is that the redundant joint must fit within the current Orion architecture, without the need for additional vehicle modification. This limitation required a design that changed the orientation of the expanding tube assemblies (XTAs), by rotating them 90deg from the standard joint configuration. The change is not trivial and affects the fracture mechanism and structural load paths. To address these changes, the design incorporates cantilevered arms on the break plate. The shock transmission and expansion of the XTA applies force to these arms and creates a prying motion to push the plate walls outward to the point of structural failure at the notched section. The 2014 test design revealed that parts could slip during functioning wasting valuable energy needed to separate the structure with only a single XTA functioning. Dual XTA functioning fully separated the assembly showing a discrepancy can be backed up with redundancy. Work on other fully redundant systems outside NASA is limited to a few patents that have not been subjected to functionality testing Design changes to prevent unwanted slippage (with ICA funding in 2015) showed success with a single XTA. The main goal for FY 2016 was to send the new Flat H RFJ to WSTF where single XTA test failures occurred back in 2014. The plan was to gain efficiency in this design by separating the Flat H RFJ with thicker ligaments with dimensions baselined in 2014. Other modifications included geometry

  2. Designing Broadband Access Networks with Triple Redundancy

    DEFF Research Database (Denmark)

    Pedersen, Jens Myrup; Riaz, Muhammad Tahir; Knudsen, Thomas Phillip

    2005-01-01

    An architecture is proposed for designing broadband access networks, which offer triple redundancy to the end users, resulting in networks providing connectivity even in case of any two independent node or line failures. Two physically independent connections are offered by fiber, and the last...... provided by some wireless solution. Based on experience with planning Fiber To The Home, the architecture is designed to meet a number of demands, making it practicable and useful in realworld network planning. The proposed wired topology is planar, and suitable for being fitted onto the road network...

  3. Validation of temperature-sensitive radio transmitters for measurement of body temperature in small animals

    NARCIS (Netherlands)

    Williams, Joseph B.; Tieleman, B. I.; Shobrak, Mohammed

    2009-01-01

    As part of a study on the core body temperature (T(b)) of desert birds, we purposed to use temperature-sensitive implantable radio transmitters. Because of the difficulty in recapturing these birds, we needed to know if these electronic devices held their calibration over the duration of normal

  4. An experimental method for making spectral emittance and surface temperature measurements of opaque surfaces

    International Nuclear Information System (INIS)

    Moore, Travis J.; Jones, Matthew R.; Tree, Dale R.; Daniel Maynes, R.; Baxter, Larry L.

    2011-01-01

    An experimental procedure has been developed to make spectral emittance and temperature measurements. The spectral emittance of an object is calculated using measurements of the spectral emissive power and of the surface temperature of the object obtained using a Fourier transform infrared (FTIR) spectrometer. A calibration procedure is described in detail which accounts for the temperature dependence of the detector. The methods used to extract the spectral emissive power and surface temperature from measured infrared spectra were validated using a blackbody radiator at known temperatures. The average error in the measured spectral emittance was 2.1% and the average difference between the temperature inferred from the recorded spectra and the temperature indicated on the blackbody radiator was 1.2%. The method was used to measure the spectral emittance of oxidized copper at various temperatures.

  5. Reliability analysis of component-level redundant topologies for solid-state fault current limiter

    Science.gov (United States)

    Farhadi, Masoud; Abapour, Mehdi; Mohammadi-Ivatloo, Behnam

    2018-04-01

    Experience shows that semiconductor switches in power electronics systems are the most vulnerable components. One of the most common ways to solve this reliability challenge is component-level redundant design. There are four possible configurations for the redundant design in component level. This article presents a comparative reliability analysis between different component-level redundant designs for solid-state fault current limiter. The aim of the proposed analysis is to determine the more reliable component-level redundant configuration. The mean time to failure (MTTF) is used as the reliability parameter. Considering both fault types (open circuit and short circuit), the MTTFs of different configurations are calculated. It is demonstrated that more reliable configuration depends on the junction temperature of the semiconductor switches in the steady state. That junction temperature is a function of (i) ambient temperature, (ii) power loss of the semiconductor switch and (iii) thermal resistance of heat sink. Also, results' sensitivity to each parameter is investigated. The results show that in different conditions, various configurations have higher reliability. The experimental results are presented to clarify the theory and feasibility of the proposed approaches. At last, levelised costs of different configurations are analysed for a fair comparison.

  6. Automatic calibration system of the temperature instrument display based on computer vision measuring

    Science.gov (United States)

    Li, Zhihong; Li, Jinze; Bao, Changchun; Hou, Guifeng; Liu, Chunxia; Cheng, Fang; Xiao, Nianxin

    2010-07-01

    With the development of computers and the techniques of dealing with pictures and computer optical measurement, various measuring techniques are maturing gradually on the basis of optical picture processing technique and using in practice. On the bases, we make use of the many years' experience and social needs in temperature measurement and computer vision measurement to come up with the completely automatic way of the temperature measurement meter with integration of the computer vision measuring technique. It realizes synchronization collection with theory temperature value, improves calibration efficiency. based on least square fitting principle, integrate data procession and the best optimize theory, rapidly and accurately realizes automation acquisition and calibration of temperature.

  7. Study on Method of Ultrasonic Gas Temperature Measure Based on FPGA

    Energy Technology Data Exchange (ETDEWEB)

    Wen, S H; Xu, F R [Institute of Electrical Engineering, Yanshan University, Qinhuangdao, 066004 (China)

    2006-10-15

    It is always a problem to measure instantaneous temperature of high-temperature and high-pressure gas. There is difficulty for the conventional method of measuring temperature to measure quickly and exactly, and the measuring precision is low, the ability of anti-jamming is bad, etc. So the article introduces a method of measuring burning gas temperature using ultrasonic based on Field-Programmable Gate Array (FPGA). The mathematic model of measuring temperature is built with the relation of velocity of ultrasonic transmitting and gas Kelvin in the ideal gas. The temperature can be figured out by measuring the difference of ultrasonic frequency {delta}f. FPGA is introduced and a high-precision data acquisition system based on digital phase-shift technology is designed. The feasibility of proposed above is confirmed more by measuring pressure of burning gas timely. Experimental result demonstrates that the error is less than 12.. and the precision is heightened to 0.8%.

  8. An all-optical system designed for the heating and temperature measurement of the diamond tool

    CSIR Research Space (South Africa)

    Masina, BN

    2012-07-01

    Full Text Available and then subsequent temperature measurement of the diamond tool. A laser beam was used as the source to raise the temperature of the diamond tool, and the resultant temperature was measured by using the blackbody principle. In this poster, we have successfully...

  9. System for improving measurement accuracy of transducer by measuring transducer temperature and resistance change using thermoelectric voltages

    Science.gov (United States)

    Anderson, Karl F. (Inventor); Parker, Allen R., Jr. (Inventor)

    1993-01-01

    A constant current loop measuring system measures a property including the temperature of a sensor responsive to an external condition being measured. The measuring system includes thermocouple conductors connected to the sensor, sensing first and second induced voltages responsive to the external condition. In addition, the measuring system includes a current generator and reverser generating a constant current, and supplying the constant current to the thermocouple conductors in forward and reverse directions generating first and second measured voltages, and a determining unit receiving the first and second measured voltages from the current generator and reverser, and determining the temperature of the sensor responsive to the first and second measured voltages.

  10. Current Options for Measuring the Surface Temperature of Dairy Cattle in a Stable Technology: Review

    Directory of Open Access Journals (Sweden)

    Kateřina Švejdová

    2016-05-01

    Full Text Available Regular measurement of the body surface temperature can help to assess the health status of animals. There are many technological possibilities of contactless temperature measurement of body surface. The important thing is to find the right part of the body whose temperature will point to the first possible symptoms and immediately react to the first signs of the disease. Disagreements about how to measure body surface temperature and accuracy of the method can occur when different measures are used. We review work showing possibilities of contactless surface temperature measurements using 1 thermography, 2 electronic transponders and 3 other possibilities of measuring the body surface temperature of dairy cattle. For example, when we scan the surface temperature with the thermal imager there can operate in individual animals confounding factors such as the nature or degree of muscular coat, which may significantly affect the results.

  11. Low-Cost Wireless Temperature Measurement: Design, Manufacture, and Testing of a PCB-Based Wireless Passive Temperature Sensor.

    Science.gov (United States)

    Yan, Dan; Yang, Yong; Hong, Yingping; Liang, Ting; Yao, Zong; Chen, Xiaoyong; Xiong, Jijun

    2018-02-10

    Low-cost wireless temperature measurement has significant value in the food industry, logistics, agriculture, portable medical equipment, intelligent wireless health monitoring, and many areas in everyday life. A wireless passive temperature sensor based on PCB (Printed Circuit Board) materials is reported in this paper. The advantages of the sensor include simple mechanical structure, convenient processing, low-cost, and easiness in integration. The temperature-sensitive structure of the sensor is a dielectric-loaded resonant cavity, consisting of the PCB substrate. The sensitive structure also integrates a patch antenna for the transmission of temperature signals. The temperature sensing mechanism of the sensor is the dielectric constant of the PCB substrate changes with temperature, which causes the resonant frequency variation of the resonator. Then the temperature can be measured by detecting the changes in the sensor's working frequency. The PCB-based wireless passive temperature sensor prototype is prepared through theoretical design, parameter analysis, software simulation, and experimental testing. The high- and low-temperature sensing performance of the sensor is tested, respectively. The resonant frequency decreases from 2.434 GHz to 2.379 GHz as the temperature increases from -40 °C to 125 °C. The fitting curve proves that the experimental data have good linearity. Three repetitive tests proved that the sensor possess well repeatability. The average sensitivity is 347.45 KHz / ℃ from repetitive measurements conducted three times. This study demonstrates the feasibility of the PCB-based wireless passive sensor, which provides a low-cost temperature sensing solution for everyday life, modern agriculture, thriving intelligent health devices, and so on, and also enriches PCB product lines and applications.

  12. Infrared temperature and gas measurements at the Haderslev power and heat plan[Denmark]; Infraroede temperatur- og gasmaelinger Haderslev Kraftvarmevaerk

    Energy Technology Data Exchange (ETDEWEB)

    Clausen, Soennik

    2007-04-15

    Report describe results from a two week measurement campaign at Haderslev Kraftvarmevaerk in 2006 as a part of PSO-project 5727 'On-line optimization of waste incinerators'. Non-contact gas temperature and gas composition was measured simultaneously with a FTIR spectrometer coupled to a water-cooled fiber-optic probe. Gas temperature and H{sub 2}O, CO{sub 2}, CO, C{sub x}H{sub y} and HCl concentrations was extracted from measured spectra of emitted thermal radiation from gas slab over a 25 cm path. Measurements where performed in different positions to obtain a overview of flow behavior and conditions during stable operation and during a step in operation conditions, e.g. changing combustion air flows. Furthermore, surface temperature of grate was monitored with a thermal camera and a cross stack reference measurement on hot outlet gas was performed with a FTIR spectrometer. (au)

  13. Apparatus using radioactive particles for measuring gas temperatures

    International Nuclear Information System (INIS)

    Compton, W.A.; Duffy, T.E.; Seegall, M.I.

    1975-01-01

    Apparatus for producing a signal indicative of the temperature of a heated gas is described comprising a beta particle source; a beta particle detector which intercepts particles emitted from said source; circuitry for converting the detector output to a signal indicative of the density of the gas; a pressure transducer for generating a signal indicative of the pressure on the gas; and circuitry for dividing the pressure signal by the density signal to produce a signal indicative of the average temperature of the gas along the path between the beta particle source and the beta particle detector. (auth)

  14. Instrument for Measuring Thermal Conductivity of Materials at Low Temperatures

    Science.gov (United States)

    Fesmire, James; Sass, Jared; Johnson, Wesley

    2010-01-01

    With the advance of polymer and other non-metallic material sciences, whole new series of polymeric materials and composites are being created. These materials are being optimized for many different applications including cryogenic and low-temperature industrial processes. Engineers need these data to perform detailed system designs and enable new design possibilities for improved control, reliability, and efficiency in specific applications. One main area of interest is cryogenic structural elements and fluid handling components and other parts, films, and coatings for low-temperature application. An important thermal property of these new materials is the apparent thermal conductivity (k-value).

  15. Radiation thermometry - non-contact temperature measurements; Strahlungsthermometrie - Temperaturen beruehrungslos messen

    Energy Technology Data Exchange (ETDEWEB)

    Hollandt, J. [Physikalisch-Technische Bundesanstalt (PTB), Braunschweig (Germany). Fachbereich Hochtemperatur- und Vakuumphysik; Hartmann, J. [Physikalisch-Technische Bundesanstalt (PTB), Braunschweig (Germany). Arbeitsgruppe Hochtemperaturskala; Gutschwager, B. [Physikalisch-Technische Bundesanstalt (PTB), Braunschweig (Germany). Arbeitsgruppe Infrarot-Strahlungsthermometrie; Struss, O. [HEITRONICS Infrarot Messtechnik GmbH (Germany)

    2007-09-15

    The temperature is one of the measurands most frequently determined, as it decisively influences physical, chemical and biological processes. To be able to evaluate, optimize, repeat and compare industrial procedures, temperatures must be measured with sufficient accuracy and worldwide uniformity. This is done with the aid of the regulations and instructions of the international temperature scale. Today, non-contact measurements of surface temperatures can be performed without problems with radiation thermometers over a temperature range from -100 C up to 3000 C. Compared to contacting measurements, radiation-thermometric temperature measurement offers a series of advantages. Radiation thermometers react very fast and the measurement is not influenced by heat supply or dissipation. This allows objects to be measured which move very fast, are energized or may experience fast temperature changes. Consequently, radiation thermometry is increasingly used for the monitoring and control of thermal processes, for maintenance and in building services engineering. The present contribution shall inform of the fundamentals of radiation-thermometric temperature measurement as well as of the construction and popular types of radiation thermometers. It will be explained how exact and worldwide uniform temperature measurement is guaranteed via the international temperature scale and the calibration of radiation thermometers. The emissivity of surfaces which is important in practical temperature measurements and some examples of industrial applications of radiation thermometers will be described. (orig.)

  16. Radiation thermometry - non-contact temperature measurements; Strahlungsthermometrie - Temperaturen beruehrungslos messen

    Energy Technology Data Exchange (ETDEWEB)

    Hollandt, J.; Hartmann, J.; Gutschwager, B. [Physikalisch-Technische Bundesanstalt, Berlin (Germany); Struss, O. [HEITRONICS Infrarot Messtechnik GmbH, Wiesbaden (Germany)

    2006-07-01

    The temperature is one of the measurands most frequently determined, as it decisively influences physical, chemical and biological processes. To be able to evaluate, optimize, repeat and compare industrial procedures, temperatures must be measured with sufficient accuracy and worldwide uniformity. This is done with the aid of the regulations and instructions of the international temperature scale. Today, non-contact measurements of surface temperatures can be performed without problems with radiation thermometers over a temperature range from -100 C up to 3000 C. Compared to contacting measurements, radiation-thermometric temperature measurement offers a series of advantages. Radiation thermometers react very fast and the measurement is not influenced by heat supply or dissipation. This allows objects to be measured which move very fast, are energized or may experience fast temperature changes. Consequently, radiation thermometry is increasingly used for the monitoring and control of thermal processes, for maintenance and in building services engineering. The present contribution shall inform of the fundamentals of radiation-thermometric temperature measurement as well as of the construction and popular types of radiation thermometers. It will be explained how exact and worldwide uniform temperature measurement is guaranteed via the international temperature scale and the calibration of radiation thermometers. The emissivity of surfaces which is important in practical temperature measurements and some examples of industrial applications of radiation thermometers will be described. (orig.)

  17. A possibility of local measurements of ion temperature in a high-temperature plasma by laser induced ionization

    International Nuclear Information System (INIS)

    Kantor, M

    2012-01-01

    A new diagnostic for local measurements of ion temperature and drift velocity in fusion plasmas is proposed in the paper. The diagnostic is based on laser induced ionization of excited hydrogen and deuterium atoms from the levels which ionization energy less than the laser photon energy. A high intensive laser beam ionizes nearly all the excited atoms in the beam region resulting in a quench of spontaneous line emission of the appropriate optical transitions. The measurements of the quenching emission have been used in the past for local measurements of hydrogen atom density in tokamak plasma. The idea of the new diagnostic is spectral resolution of the quenching emission. The measured spectrum relates directly to the velocity distribution of the excited atoms. This distribution is strongly coupled to the distribution of the hydrogen atoms at the ground state. So, the spectral resolution of quenching emission is a way of local measurements of the temperature and drift velocity of hydrogen atoms in plasma. The temperature of hydrogen atoms is well coupled to the local ion temperature as long as the mean free path of the atoms is shorter than the ion gradient length in plasma. In this case the new diagnostic can provide local measurements of ion temperature in plasma. The paper considers technical capabilities of the diagnostic, physical restrictions of its application and interpretation of the measurements.

  18. Diabetes classification using a redundancy reduction preprocessor

    Directory of Open Access Journals (Sweden)

    Áurea Celeste Ribeiro

    Full Text Available Introduction Diabetes patients can benefit significantly from early diagnosis. Thus, accurate automated screening is becoming increasingly important due to the wide spread of that disease. Previous studies in automated screening have found a maximum accuracy of 92.6%. Methods This work proposes a classification methodology based on efficient coding of the input data, which is carried out by decreasing input data redundancy using well-known ICA algorithms, such as FastICA, JADE and INFOMAX. The classifier used in the task to discriminate diabetics from non-diaibetics is the one class support vector machine. Classification tests were performed using noninvasive and invasive indicators. Results The results suggest that redundancy reduction increases one-class support vector machine performance when discriminating between diabetics and nondiabetics up to an accuracy of 98.47% while using all indicators. By using only noninvasive indicators, an accuracy of 98.28% was obtained. Conclusion The ICA feature extraction improves the performance of the classifier in the data set because it reduces the statistical dependence of the collected data, which increases the ability of the classifier to find accurate class boundaries.

  19. Kinematically Optimal Robust Control of Redundant Manipulators

    Science.gov (United States)

    Galicki, M.

    2017-12-01

    This work deals with the problem of the robust optimal task space trajectory tracking subject to finite-time convergence. Kinematic and dynamic equations of a redundant manipulator are assumed to be uncertain. Moreover, globally unbounded disturbances are allowed to act on the manipulator when tracking the trajectory by the endeffector. Furthermore, the movement is to be accomplished in such a way as to minimize both the manipulator torques and their oscillations thus eliminating the potential robot vibrations. Based on suitably defined task space non-singular terminal sliding vector variable and the Lyapunov stability theory, we derive a class of chattering-free robust kinematically optimal controllers, based on the estimation of transpose Jacobian, which seem to be effective in counteracting both uncertain kinematics and dynamics, unbounded disturbances and (possible) kinematic and/or algorithmic singularities met on the robot trajectory. The numerical simulations carried out for a redundant manipulator of a SCARA type consisting of the three revolute kinematic pairs and operating in a two-dimensional task space, illustrate performance of the proposed controllers as well as comparisons with other well known control schemes.

  20. Design of a temperature measurement and feedback control system based on an improved magnetic nanoparticle thermometer

    Science.gov (United States)

    Du, Zhongzhou; Sun, Yi; Liu, Jie; Su, Rijian; Yang, Ming; Li, Nana; Gan, Yong; Ye, Na

    2018-04-01

    Magnetic fluid hyperthermia, as a novel cancer treatment, requires precise temperature control at 315 K-319 K (42 °C-46 °C). However, the traditional temperature measurement method cannot obtain the real-time temperature in vivo, resulting in a lack of temperature feedback during the heating process. In this study, the feasibility of temperature measurement and feedback control using magnetic nanoparticles is proposed and demonstrated. This technique could be applied in hyperthermia. Specifically, the triangular-wave temperature measurement method is improved by reconstructing the original magnetization response of magnetic nanoparticles based on a digital phase-sensitive detection algorithm. The standard deviation of the temperature in the magnetic nanoparticle thermometer is about 0.1256 K. In experiments, the temperature fluctuation of the temperature measurement and feedback control system using magnetic nanoparticles is less than 0.5 K at the expected temperature of 315 K. This shows the feasibility of the temperature measurement method for temperature control. The method provides a new solution for temperature measurement and feedback control in hyperthermia.

  1. Learners misperceive the benefits of redundant text in multimedia learning.

    Science.gov (United States)

    Fenesi, Barbara; Kim, Joseph A

    2014-01-01

    Research on metacognition has consistently demonstrated that learners fail to endorse instructional designs that produce benefits to memory, and often prefer designs that actually impair comprehension. Unlike previous studies in which learners were only exposed to a single multimedia design, the current study used a within-subjects approach to examine whether exposure to both redundant text and non-redundant text multimedia presentations improved learners' metacognitive judgments about presentation styles that promote better understanding. A redundant text multimedia presentation containing narration paired with verbatim on-screen text (Redundant) was contrasted with two non-redundant text multimedia presentations: (1) narration paired with images and minimal text (Complementary) or (2) narration paired with minimal text (Sparse). Learners watched presentation pairs of either Redundant + Complementary, or Redundant + Sparse. Results demonstrate that Complementary and Sparse presentations produced highest overall performance on the final comprehension assessment, but the Redundant presentation produced highest perceived understanding and engagement ratings. These findings suggest that learners misperceive the benefits of redundant text, even after direct exposure to a non-redundant, effective presentation.

  2. The human brain maintains contradictory and redundant auditory sensory predictions.

    Directory of Open Access Journals (Sweden)

    Marika Pieszek

    Full Text Available Computational and experimental research has revealed that auditory sensory predictions are derived from regularities of the current environment by using internal generative models. However, so far, what has not been addressed is how the auditory system handles situations giving rise to redundant or even contradictory predictions derived from different sources of information. To this end, we measured error signals in the event-related brain potentials (ERPs in response to violations of auditory predictions. Sounds could be predicted on the basis of overall probability, i.e., one sound was presented frequently and another sound rarely. Furthermore, each sound was predicted by an informative visual cue. Participants' task was to use the cue and to discriminate the two sounds as fast as possible. Violations of the probability based prediction (i.e., a rare sound as well as violations of the visual-auditory prediction (i.e., an incongruent sound elicited error signals in the ERPs (Mismatch Negativity [MMN] and Incongruency Response [IR]. Particular error signals were observed even in case the overall probability and the visual symbol predicted different sounds. That is, the auditory system concurrently maintains and tests contradictory predictions. Moreover, if the same sound was predicted, we observed an additive error signal (scalp potential and primary current density equaling the sum of the specific error signals. Thus, the auditory system maintains and tolerates functionally independently represented redundant and contradictory predictions. We argue that the auditory system exploits all currently active regularities in order to optimally prepare for future events.

  3. Reliability and mass analysis of dynamic power conversion systems with parallel or standby redundancy

    Science.gov (United States)

    Juhasz, Albert J.; Bloomfield, Harvey S.

    1987-01-01

    A combinatorial reliability approach was used to identify potential dynamic power conversion systems for space mission applications. A reliability and mass analysis was also performed, specifically for a 100-kWe nuclear Brayton power conversion system with parallel redundancy. Although this study was done for a reactor outlet temperature of 1100 K, preliminary system mass estimates are also included for reactor outlet temperatures ranging up to 1500 K.

  4. Reliability and mass analysis of dynamic power conversion systems with parallel of standby redundancy

    Science.gov (United States)

    Juhasz, A. J.; Bloomfield, H. S.

    1985-01-01

    A combinatorial reliability approach is used to identify potential dynamic power conversion systems for space mission applications. A reliability and mass analysis is also performed, specifically for a 100 kWe nuclear Brayton power conversion system with parallel redundancy. Although this study is done for a reactor outlet temperature of 1100K, preliminary system mass estimates are also included for reactor outlet temperatures ranging up to 1500 K.

  5. Laser measure of sea salinity, temperature and turbidity in depth

    Science.gov (United States)

    Hirschberg, J. G.; Wouters, A. W.; Byrne, J. D.

    1974-01-01

    A method is described in which a pulsed laser is used to probe the sea. Backscattered light is analyzed in time, intensity and wavelength. Tyndall, Raman and Brillouin scattering are used to obtain the backscatter turbidity, sound velocity, salinity, and the temperature as a function of depth.

  6. Adiabatic temperature change from non-adiabatic measurements

    Czech Academy of Sciences Publication Activity Database

    Carvalho, A.M.G.; Mejía, C.S.; Ponte, C.A.; Silva, L.E.L.; Kaštil, Jiří; Kamarád, Jiří; Gomes, A.M.

    2016-01-01

    Roč. 122, č. 3 (2016), s. 1-5, č. článku 246. ISSN 0947-8396 Institutional support: RVO:68378271 Keywords : magnetocaloric effect * adiabatic temperature change * calorimetric device * gadolinium Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.455, year: 2016

  7. Determination of the yield locus by means of temperature measurement

    NARCIS (Netherlands)

    Banabic, D.; Huetink, Han

    2006-01-01

    The paper presents a theoretical background of the thermo-graphical method of determining the yield locus. The analytical expression of the temperature variation of the specimen deformed in the elastic state is determined starting from the first law of thermodynamics. The experimental method for

  8. Measurement of surface temperature and emissivity by a multitemperature method for Fourier-transform infrared spectrometers

    DEFF Research Database (Denmark)

    Clausen, Sønnik; Morgenstjerne, Axel; Rathmann, Ole

    1996-01-01

    Surface temperatures are estimated with high precision based on a multitemperature method for Fourier-transform spectrometers. The method is based on Planck's radiation law and a nonlinear least-squares fitting algorithm applied to two or more spectra at different sample temperatures and a single...... of blackbody sources are estimated with an uncertainty of 0.2-2 K. The method is demonstrated for measuring the spectral emissivity of a brass specimen and an oxidized nickel specimen. (C) 1996 Optical Society of America...... measurement at a known sample temperature, for example, at ambient temperature. The temperature of the sample surface can be measured rather easily at ambient temperature. The spectrum at ambient temperature is used to eliminate background effects from spectra as measured at other surface temperatures...

  9. Ultrasonic measurement of elastic constants at temperatures from 20 to 11000C

    International Nuclear Information System (INIS)

    Moyer, M.W.; Hammond, J.P.

    1976-09-01

    Measurements of the elastic moduli at temperatures from 20 to 1100 0 C of a number of materials of interest in the Liquid Metal Fast Breeder Reactor and the High Temperature Gas Reactor were accomplished using acoustic techniques. A two-step process was required to complete the measurements. First, the acoustic velocities were measured accurately on bulk samples at room temperature, then a wire sample was used to make elevated-temperature measurements. A computer was used to calculate the moduli and plot the data. A detailed summary has been made of the sources of error and a calculation of the precision of the measurements is given

  10. Design of a low-cost system for electrical conductivity measurements of high temperature

    Science.gov (United States)

    Singh, Yadunath

    2018-05-01

    It is always a curiosity and interest among researchers working in the field of material science to know the impact of high temperature on the physical and transport properties of the materials. In this paper, we report on the design and working of a system for the measurements of electrical resistivity with high temperature. It was designed at our place and successively used for these measurements in the temperature range from room temperature to 500 ˚C.

  11. Comparison between auricular and standard rectal thermometers for the measurement of body temperature in dogs.

    Science.gov (United States)

    Sousa, Marlos G; Carareto, Roberta; Pereira-Junior, Valdo A; Aquino, Monally C C

    2011-04-01

    Although the rectal mucosa remains the traditional site for measuring body temperature in dogs, an increasing number of clinicians have been using auricular temperature to estimate core body temperature. In this study, 88 mature healthy dogs had body temperatures measured with auricular and rectal thermometers. The mean temperature and confidence intervals were similar for each method, but Bland-Altman plots showed high biases and limits of agreement unacceptable for clinical purposes. The results indicate that auricular and rectal temperatures should not be interpreted interchangeably.

  12. IR Camera Validation of IGBT Junction Temperature Measurement via Peak Gate Current

    DEFF Research Database (Denmark)

    Baker, Nick; Dupont, Laurent; Munk-Nielsen, Stig

    2017-01-01

    partial bond-wire lift-off. Results are also compared with a traditional electrical temperature measurement method: the voltage drop under low current (VCE(low)). In all cases, the IGPeak method is found to provide a temperature slightly overestimating the temperature of the gate pad. Consequently, both...... the gate pad position and chip temperature distribution influence whether the measurement is representative of the mean junction temperature. These results remain consistent after chips are degraded through bondwire lift-off. In a paralleled IGBT configuration with non-negligible temperature disequilibrium...

  13. Very high temperature measurements: Applications to nuclear reactor safety tests

    International Nuclear Information System (INIS)

    Parga, Clemente-Jose

    2013-01-01

    This PhD dissertation focuses on the improvement of very high temperature thermometry (1100 deg. C to 2480 deg. C), with special emphasis on the application to the field of nuclear reactor safety and severe accident research. Two main projects were undertaken to achieve this objective: - The development, testing and transposition of high-temperature fixed point (HTFP) metal-carbon eutectic cells, from metrology laboratory precision (±0.001 deg. C) to applied research with a reasonable degradation of uncertainties (±3-5 deg. C). - The corrosion study and metallurgical characterization of Type-C thermocouple (service temp. 2300 deg. C) prospective sheath material was undertaken to extend the survivability of TCs used for molten metallic/oxide corium thermometry (below 2000 deg. C)

  14. In situ response time measurements of RTD temperature sensors

    International Nuclear Information System (INIS)

    Goncalves, I.M.P.

    1985-01-01

    The loop-current-step-response test provides a mean for determining the time constant of resistence thermometers. The test consist in heating the sensor a few degrees above ambient temperature by causing a step pertubation in the electric current that flows through the sensor leads. The developed mathematical transformation permits to use data collected during the internal heating transient to predict the sensor response to perturbations in fluid temperature. Experimental data obtained show that the time constant determined by method is within 15 percent of true value. The loop-current-step-response test is a remote in situ test, which can be performed with the sensor installed in the process. Consequently it takes account the local heat transfer conditions, and appropriated for nuclear power plants, where sensors are installed in points of difficult access. (author) [pt

  15. Lidar measurements of mesospheric temperature inversion at a low latitude

    Directory of Open Access Journals (Sweden)

    V. Siva Kumar

    2001-08-01

    Full Text Available The Rayleigh lidar data collected on 119 nights from March 1998 to February 2000 were used to study the statistical characteristics of the low latitude mesospheric temperature inversion observed over Gadanki (13.5° N, 79.2° E, India. The occurrence frequency of the inversion showed semiannual variation with maxima in the equinoxes and minima in the summer and winter, which was quite different from that reported for the mid-latitudes. The peak of the inversion layer was found to be confined to the height range of 73 to 79 km with the maximum occurrence centered around 76 km, with a weak seasonal dependence that fits well to an annual cycle with a maximum in June and a minimum in December. The magnitude of the temperature deviation associated with the inversion was found to be as high as 32 K, with the most probable value occurring at about 20 K. Its seasonal dependence seems to follow an annual cycle with a maximum in April and a minimum in October. The observed characteristics of the inversion layer are compared with that of the mid-latitudes and discussed in light of the current understanding of the source mechanisms.Key words. Atmospheric composition and structure (pressure, density and temperature. Meterology and atmospheric dynamics (climatology

  16. Lidar measurements of mesospheric temperature inversion at a low latitude

    Directory of Open Access Journals (Sweden)

    V. Siva Kumar

    Full Text Available The Rayleigh lidar data collected on 119 nights from March 1998 to February 2000 were used to study the statistical characteristics of the low latitude mesospheric temperature inversion observed over Gadanki (13.5° N, 79.2° E, India. The occurrence frequency of the inversion showed semiannual variation with maxima in the equinoxes and minima in the summer and winter, which was quite different from that reported for the mid-latitudes. The peak of the inversion layer was found to be confined to the height range of 73 to 79 km with the maximum occurrence centered around 76 km, with a weak seasonal dependence that fits well to an annual cycle with a maximum in June and a minimum in December. The magnitude of the temperature deviation associated with the inversion was found to be as high as 32 K, with the most probable value occurring at about 20 K. Its seasonal dependence seems to follow an annual cycle with a maximum in April and a minimum in October. The observed characteristics of the inversion layer are compared with that of the mid-latitudes and discussed in light of the current understanding of the source mechanisms.

    Key words. Atmospheric composition and structure (pressure, density and temperature. Meterology and atmospheric dynamics (climatology

  17. Thermal conductivity measurements of PTFE and Al2O3 ceramic at sub-Kelvin temperatures

    Science.gov (United States)

    Drobizhev, Alexey; Reiten, Jared; Singh, Vivek; Kolomensky, Yury G.

    2017-07-01

    The design of low temperature bolometric detectors for rare event searches necessitates careful selection and characterization of structural materials based on their thermal properties. We measure the thermal conductivities of polytetrafluoroethylene (PTFE) and Al2O3 ceramic (alumina) in the temperature ranges of 0.17-0.43 K and 0.1-1.3 K, respectively. For the former, we observe a quadratic temperature dependence across the entire measured range. For the latter, we see a cubic dependence on temperature above 0.3 K, with a linear contribution below that temperature. This paper presents our measurement techniques, results, and theoretical discussions.

  18. Comparison of rectal, tympanic membrane and axillary temperature measurement methods in dogs.

    Science.gov (United States)

    Lamb, V; McBrearty, A R

    2013-11-30

    The aim of this study was to compare axillary and tympanic membrane (TM) temperature measurements to rectal temperature in a large group of clinical canine patients. We also sought to ascertain whether certain factors affected the differences between the measurements and to compare the ease of measurement. Axillary temperatures were easy to obtain but tended to be lower than rectal readings (median difference 0.6°C). In 54.7 per cent of dogs there was a difference of >0.5°C between the two readings. Weight, coat length, body condition score and breed size were significantly associated with the difference between the rectal and axillary temperature. TM temperatures were more similar to rectal temperatures (median difference 0°C) but in 25 per cent of dogs, there was a difference of >0.5°C between rectal and TM readings. TM measurements were less well tolerated than axillary measurements. None of the factors assessed were associated with the difference between the rectal and TM temperature. As a difference of >0.5°C has previously been described as unacceptable for different methods of temperature measurement, neither axillary nor TM temperatures are interchangeable with rectal temperatures for the measurement of body temperature.

  19. Effects of wall temperature on skin-friction measurements by oil-film interferometry

    International Nuclear Information System (INIS)

    Bottini, H; Kurita, M; Iijima, H; Fukagata, K

    2015-01-01

    Wind-tunnel skin-friction measurements with thin-oil-film interferometry have been taken on an aluminum sample to investigate the effects of wall temperature on the accuracy of the technique. The sample has been flush-mounted onto a flat plate with an electric heater at its bottom and mirror-smooth temperature-sensitive paint sprayed on its top. The heater has varied the sample temperature from ambient to 328 K, and the paint has permitted wall temperature measurements on the same area of the skin-friction measurements and during the same test. The measured wall temperatures have been used to calculate the correct oil viscosities, and these viscosities and the constant nominal viscosity at 298 K have been used to calculate two different sets of skin-friction coefficients. These sets have been compared to each other and with theoretical values. This comparison shows that the effects of wall temperature on the accuracy of skin-friction measurements are sensible, and more so as wall temperature differs from 298 K. Nonetheless, they are effectively neutralized by the use of wall temperature measurements in combination with the correct oil viscosity–temperature law. In this regard, the special temperature-sensitive paint developed for this study shows advantages with respect to more traditional wall temperature measurement techniques. (paper)

  20. Optimal redundant systems for works with random processing time

    International Nuclear Information System (INIS)

    Chen, M.; Nakagawa, T.

    2013-01-01

    This paper studies the optimal redundant policies for a manufacturing system processing jobs with random working times. The redundant units of the parallel systems and standby systems are subject to stochastic failures during the continuous production process. First, a job consisting of only one work is considered for both redundant systems and the expected cost functions are obtained. Next, each redundant system with a random number of units is assumed for a single work. The expected cost functions and the optimal expected numbers of units are derived for redundant systems. Subsequently, the production processes of N tandem works are introduced for parallel and standby systems, and the expected cost functions are also summarized. Finally, the number of works is estimated by a Poisson distribution for the parallel and standby systems. Numerical examples are given to demonstrate the optimization problems of redundant systems

  1. Reliability Analysis Multiple Redundancy Controller for Nuclear Safety Systems

    International Nuclear Information System (INIS)

    Son, Gwangseop; Kim, Donghoon; Son, Choulwoong

    2013-01-01

    This controller is configured for multiple modular redundancy (MMR) composed of dual modular redundancy (DMR) and triple modular redundancy (TMR). The architecture of MRC is briefly described, and the Markov model is developed. Based on the model, the reliability and Mean Time To Failure (MTTF) are analyzed. In this paper, the architecture of MRC for nuclear safety systems is described. The MRC is configured for multiple modular redundancy (MMR) composed of dual modular redundancy (DMR) and triple modular redundancy (TMR). Markov models for MRC architecture was developed, and then the reliability was analyzed by using the model. From the reliability analyses for the MRC, it is obtained that the failure rate of each module in the MRC should be less than 2 Χ 10 -4 /hour and the MTTF average increase rate depending on FCF increment, i. e. ΔMTTF/ΔFCF, is 4 months/0.1

  2. Computation and measurement of air temperature distribution of an industrial melt blowing die

    Directory of Open Access Journals (Sweden)

    Wu Li-Li

    2014-01-01

    Full Text Available The air flow field of the dual slot die on an HDF-6D melt blowing non-woven equipment is computed numerically. A temperature measurement system is built to measure air temperatures. The computation results tally with the measured results proving the correctness of the computation. The results have great valuable significance in the actual melt blowing production.

  3. The validity of tympanic and exhaled breath temperatures for core temperature measurement

    International Nuclear Information System (INIS)

    Flouris, Andreas D; Cheung, Stephen S

    2010-01-01

    We examined the efficacy of tympanic (T ty ) and exhaled breath (T X ) temperatures as indices of rectal temperature (T re ) by applying heat (condition A) and cold (condition B) in a dynamic A-B-A-B sequence. Fifteen healthy adults (8 men; 7 women; 24.9 ± 4.6 years) volunteered. Following a 15 min baseline period, participants entered a water tank maintained at 42 °C water temperature and passively rested until their T re increased by 0.5 °C above baseline. Thereafter, they entered a different water tank maintained at 12 °C water temperature until their T re decreased by 0.5 °C below baseline. This procedure was repeated twice (i.e. A-B-A-B). T ty demonstrated moderate response delays to the repetitive changes in thermal balance, whereas T X and T re responded relatively fast. Both T ty and T X correlated significantly with T re (P < 0.05). Linear regression models were used to predict T re based on T ty and T X . The predicted values from both models correlated significantly with T re (P < 0.05) and followed the changes in T re during the A-B-A-B thermal protocol. While some mean differences with T re were observed (P < 0.05), the 95% limits of agreement were acceptable for both models. It is concluded that the calculated models based on tympanic and exhaled breath temperature are valid indicators of core temperature. (note)

  4. Improving the Accuracy of Satellite Sea Surface Temperature Measurements by Explicitly Accounting for the Bulk-Skin Temperature Difference

    Science.gov (United States)

    Castro, Sandra L.; Emery, William J.

    2002-01-01

    The focus of this research was to determine whether the accuracy of satellite measurements of sea surface temperature (SST) could be improved by explicitly accounting for the complex temperature gradients at the surface of the ocean associated with the cool skin and diurnal warm layers. To achieve this goal, work centered on the development and deployment of low-cost infrared radiometers to enable the direct validation of satellite measurements of skin temperature. During this one year grant, design and construction of an improved infrared radiometer was completed and testing was initiated. In addition, development of an improved parametric model for the bulk-skin temperature difference was completed using data from the previous version of the radiometer. This model will comprise a key component of an improved procedure for estimating the bulk SST from satellites. The results comprised a significant portion of the Ph.D. thesis completed by one graduate student and they are currently being converted into a journal publication.

  5. The Relationship Between Radiative Forcing and Temperature. What Do Statistical Analyses of the Instrumental Temperature Record Measure?

    International Nuclear Information System (INIS)

    Kaufmann, R.K.; Kauppi, H.; Stock, J.H.

    2006-01-01

    Comparing statistical estimates for the long-run temperature effect of doubled CO2 with those generated by climate models begs the question, is the long-run temperature effect of doubled CO2 that is estimated from the instrumental temperature record using statistical techniques consistent with the transient climate response, the equilibrium climate sensitivity, or the effective climate sensitivity. Here, we attempt to answer the question, what do statistical analyses of the observational record measure, by using these same statistical techniques to estimate the temperature effect of a doubling in the atmospheric concentration of carbon dioxide from seventeen simulations run for the Coupled Model Intercomparison Project 2 (CMIP2). The results indicate that the temperature effect estimated by the statistical methodology is consistent with the transient climate response and that this consistency is relatively unaffected by sample size or the increase in radiative forcing in the sample

  6. Measurement of body temperature in normothermic and febrile rats: Limitations of using rectal thermometry.

    Science.gov (United States)

    Dangarembizi, Rachael; Erlwanger, Kennedy H; Mitchell, Duncan; Hetem, Robyn S; Madziva, Michael T; Harden, Lois M

    2017-10-01

    Stress-induced hyperthermia following rectal thermometry is reported in normothermic rats, but appears to be muted or even absent in febrile rats. We therefore investigated whether the use of rectal thermometry affects the accuracy of temperature responses recorded in normothermic and febrile rats. Using intra-abdominally implanted temperature-sensitive radiotelemeters we measured the temperature response to rectal temperature measurement in male Sprague Dawley rats (~200g) injected subcutaneously with Brewer's yeast (20ml/kg of a 20% Brewer's yeast solution=4000mg/kg) or saline (20ml/kg of 0.9% saline). Rats had been pre-exposed to, or were naive to rectal temperature measurement before the injection. The first rectal temperature measurement was taken in the plateau phase of the fever (18h after injection) and at hourly intervals thereafter. In normothermic rats, rectal temperature measurement was associated with an increase in abdominal temperature (0.66±0.27°C) that had a rapid onset (5-10min), peaked at 15-20min and lasted for 35-50min. The hyperthermic response to rectal temperature measurement was absent in febrile rats. Exposure to rectal temperature measurement on two previous occasions did not reduce the hyperthermia. There was a significant positive linear association between temperatures recorded using the two methods, but the agreement interval identified that rectal temperature measured with a thermocouple probe could either be 0.7°C greater or 0.5°C lower than abdominal temperature measured with radiotelemeter. Thus, due to stress-induced hyperthermia, rectal thermometry does not ensure accurate recording of body temperature in short-spaced, intermittent intervals in normothermic and febrile rats. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Hotspot electron temperature from x-ray continuum measurements on the NIF

    International Nuclear Information System (INIS)

    Jarrott, L. C.; Benedetti, L. R.; Chen, H.; Izumi, N.; Khan, S. F.; Ma, T.; Nagel, S. R.; Landen, O. L.; Pak, A.; Patel, P. K.; Schneider, M.; Scott, H. A.

    2016-01-01

    We report on measurements of the electron temperature in the hotspot of inertially confined, layered, spherical implosions on the National Ignition Facility using a differential filtering diagnostic. Measurements of the DT and DD ion temperatures using neutron time-of-flight detectors are complicated by the contribution of hot spot motion to the peak width, which produce an apparent temperature higher than the thermal temperature. The electron temperature is not sensitive to this non-thermal velocity and is thus a valuable input to interpreting the stagnated hot spot conditions. Here we show that the current differential filtering diagnostic provides insufficient temperature resolution for the hot spot temperatures of interest. We then propose a new differential filter configuration utilizing larger pinhole size to increase spectral fluence, as well as thicker filtration. This new configuration will improve measurement uncertainty by more than a factor of three, allowing for a more accurate hotspot temperature.

  8. Hotspot electron temperature from x-ray continuum measurements on the NIF

    Science.gov (United States)

    Jarrott, L. C.; Benedetti, L. R.; Chen, H.; Izumi, N.; Khan, S. F.; Ma, T.; Nagel, S. R.; Landen, O. L.; Pak, A.; Patel, P. K.; Schneider, M.; Scott, H. A.

    2016-11-01

    We report on measurements of the electron temperature in the hotspot of inertially confined, layered, spherical implosions on the National Ignition Facility using a differential filtering diagnostic. Measurements of the DT and DD ion temperatures using neutron time-of-flight detectors are complicated by the contribution of hot spot motion to the peak width, which produce an apparent temperature higher than the thermal temperature. The electron temperature is not sensitive to this non-thermal velocity and is thus a valuable input to interpreting the stagnated hot spot conditions. Here we show that the current differential filtering diagnostic provides insufficient temperature resolution for the hot spot temperatures of interest. We then propose a new differential filter configuration utilizing larger pinhole size to increase spectral fluence, as well as thicker filtration. This new configuration will improve measurement uncertainty by more than a factor of three, allowing for a more accurate hotspot temperature.

  9. Hotspot electron temperature from x-ray continuum measurements on the NIF.

    Science.gov (United States)

    Jarrott, L C; Benedetti, L R; Chen, H; Izumi, N; Khan, S F; Ma, T; Nagel, S R; Landen, O L; Pak, A; Patel, P K; Schneider, M; Scott, H A

    2016-11-01

    We report on measurements of the electron temperature in the hotspot of inertially confined, layered, spherical implosions on the National Ignition Facility using a differential filtering diagnostic. Measurements of the DT and DD ion temperatures using neutron time-of-flight detectors are complicated by the contribution of hot spot motion to the peak width, which produce an apparent temperature higher than the thermal temperature. The electron temperature is not sensitive to this non-thermal velocity and is thus a valuable input to interpreting the stagnated hot spot conditions. Here we show that the current differential filtering diagnostic provides insufficient temperature resolution for the hot spot temperatures of interest. We then propose a new differential filter configuration utilizing larger pinhole size to increase spectral fluence, as well as thicker filtration. This new configuration will improve measurement uncertainty by more than a factor of three, allowing for a more accurate hotspot temperature.

  10. Hotspot electron temperature from x-ray continuum measurements on the NIF

    Energy Technology Data Exchange (ETDEWEB)

    Jarrott, L. C., E-mail: jarrott1@llnl.gov; Benedetti, L. R.; Chen, H.; Izumi, N.; Khan, S. F.; Ma, T.; Nagel, S. R.; Landen, O. L.; Pak, A.; Patel, P. K.; Schneider, M.; Scott, H. A. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    2016-11-15

    We report on measurements of the electron temperature in the hotspot of inertially confined, layered, spherical implosions on the National Ignition Facility using a differential filtering diagnostic. Measurements of the DT and DD ion temperatures using neutron time-of-flight detectors are complicated by the contribution of hot spot motion to the peak width, which produce an apparent temperature higher than the thermal temperature. The electron temperature is not sensitive to this non-thermal velocity and is thus a valuable input to interpreting the stagnated hot spot conditions. Here we show that the current differential filtering diagnostic provides insufficient temperature resolution for the hot spot temperatures of interest. We then propose a new differential filter configuration utilizing larger pinhole size to increase spectral fluence, as well as thicker filtration. This new configuration will improve measurement uncertainty by more than a factor of three, allowing for a more accurate hotspot temperature.

  11. Monitoring system for accuracy and reliability characteristics of standard temperature measurements in WWER-440 reactors

    International Nuclear Information System (INIS)

    Stanc, S.; Repa, M.

    2001-01-01

    Description of a monitoring system for accuracy and reliability characteristics of standard temperature measurements in WWER-440 reactors and benefits obtained from its use are shown in the presentation. As standard reactor temperature measurement, coolant temperature measurement at fuel assembly outlets and in loops, entered into the In-Reactor Control System , are considered. Such systems have been implemented at two V-230 reactors and are under implementation at other four V-213 reactors. (Authors)

  12. Predicting genome-wide redundancy using machine learning

    Directory of Open Access Journals (Sweden)

    Shasha Dennis E

    2010-11-01

    Full Text Available Abstract Background Gene duplication can lead to genetic redundancy, which masks the function of mutated genes in genetic analyses. Methods to increase sensitivity in identifying genetic redundancy can improve the efficiency of reverse genetics and lend insights into the evolutionary outcomes of gene duplication. Machine learning techniques are well suited to classifying gene family members into redundant and non-redundant gene pairs in model species where sufficient genetic and genomic data is available, such as Arabidopsis thaliana, the test case used here. Results Machine learning techniques that combine multiple attributes led to a dramatic improvement in predicting genetic redundancy over single trait classifiers alone, such as BLAST E-values or expression correlation. In withholding analysis, one of the methods used here, Support Vector Machines, was two-fold more precise than single attribute classifiers, reaching a level where the majority of redundant calls were correctly labeled. Using this higher confidence in identifying redundancy, machine learning predicts that about half of all genes in Arabidopsis showed the signature of predicted redundancy with at least one but typically less than three other family members. Interestingly, a large proportion of predicted redundant gene pairs were relatively old duplications (e.g., Ks > 1, suggesting that redundancy is stable over long evolutionary periods. Conclusions Machine learning predicts that most genes will have a functionally redundant paralog but will exhibit redundancy with relatively few genes within a family. The predictions and gene pair attributes for Arabidopsis provide a new resource for research in genetics and genome evolution. These techniques can now be applied to other organisms.

  13. Redundancy and Reliability for an HPC Data Centre

    OpenAIRE

    Erhan Yılmaz

    2012-01-01

    Defining a level of redundancy is a strategic question when planning a new data centre, as it will directly impact the entire design of the building as well as the construction and operational costs. It will also affect how to integrate future extension plans into the design. Redundancy is also a key strategic issue when upgrading or retrofitting an existing facility. Redundancy is a central strategic question to any business that relies on data centres for its operation. In th...

  14. Study of redundant Models in reliability prediction of HXMT's HES

    International Nuclear Information System (INIS)

    Wang Jinming; Liu Congzhan; Zhang Zhi; Ji Jianfeng

    2010-01-01

    Two redundant equipment structures of HXMT's HES are proposed firstly, the block backup and dual system cold-redundancy. Then prediction of the reliability is made by using parts count method. Research of comparison and analysis is also performed on the two proposals. A conclusion is drawn that a higher reliability and longer service life could be offered by taking a redundant equipment structure of block backup. (authors)

  15. Reliability of redundant structures of nuclear reactor protection systems

    International Nuclear Information System (INIS)

    Vojnovic, B.

    1983-01-01

    In this paper, reliability of various redundant structures of PWR protection systems has been analysed. Structures of reactor tip systems as well as the systems for activation of safety devices have been presented. In all those systems redundancy is achieved by means of so called majority voting logic ('r out of n' structures). Different redundant devices have been compared, concerning probability of occurrence of safe as well as unsafe failures. (author)

  16. MICROWAVE MEASUREMENT OF REFRACTORY MATERIALS AT HIGH-TEMPERATURE

    International Nuclear Information System (INIS)

    Kharkovsky, S.; Zoughi, R.; Smith, J.; Davis, B.; Limmer, R.

    2009-01-01

    Knowledge of the electrical behavior of refractory materials may enable the development and optimization of microwave nondestructive techniques to detect and evaluate changes in their physical properties while the materials are in service. This paper presents the results of a limited and preliminary investigation in which two refractory materials (dense chrome and dense zircon) were subjected to increasing temperature in a furnace and in which a frequency-modulated continuous-wave radar operating in the frequency range of 8-18 GHz radar was used to evaluate their attenuation properties.

  17. Microwave Measurement of Refractory Materials at High-Temperature

    Science.gov (United States)

    Kharkovsky, S.; Zoughi, R.; Smith, J.; Davis, B.; Limmer, R.

    2009-03-01

    Knowledge of the electrical behavior of refractory materials may enable the development and optimization of microwave nondestructive techniques to detect and evaluate changes in their physical properties while the materials are in service. This paper presents the results of a limited and preliminary investigation in which two refractory materials (dense chrome and dense zircon) were subjected to increasing temperature in a furnace and in which a frequency-modulated continuous-wave radar operating in the frequency range of 8-18 GHz radar was used to evaluate their attenuation properties.

  18. Redundant information encoding in QED during decoherence

    Science.gov (United States)

    Tuziemski, J.; Witas, P.; Korbicz, J. K.

    2018-01-01

    Broadly understood decoherence processes in quantum electrodynamics, induced by neglecting either the radiation [L. Landau, Z. Phys. 45, 430 (1927), 10.1007/BF01343064] or the charged matter [N. Bohr and L. Rosenfeld, K. Danske Vidensk. Selsk, Math.-Fys. Medd. XII, 8 (1933)], have been studied from the dawn of the theory. However, what happens in between, when a part of the radiation may be observed, as is the case in many real-life situations, has not been analyzed yet. We present such an analysis for a nonrelativistic, pointlike charge and thermal radiation. In the dipole approximation, we solve the dynamics and show that there is a regime where, despite the noise, the observed field carries away almost perfect and hugely redundant information about the charge momentum. We analyze a partial charge-field state and show that it approaches a so-called spectrum broadcast structure.

  19. Timing control by redundant inhibitory neuronal circuits

    Energy Technology Data Exchange (ETDEWEB)

    Tristan, I., E-mail: itristan@ucsd.edu; Rulkov, N. F.; Huerta, R.; Rabinovich, M. [BioCircuits Institute, University of California, San Diego, La Jolla, California 92093-0402 (United States)

    2014-03-15

    Rhythms and timing control of sequential activity in the brain is fundamental to cognition and behavior. Although experimental and theoretical studies support the understanding that neuronal circuits are intrinsically capable of generating different time intervals, the dynamical origin of the phenomenon of functionally dependent timing control is still unclear. Here, we consider a new mechanism that is related to the multi-neuronal cooperative dynamics in inhibitory brain motifs consisting of a few clusters. It is shown that redundancy and diversity of neurons within each cluster enhances the sensitivity of the timing control with the level of neuronal excitation of the whole network. The generality of the mechanism is shown to work on two different neuronal models: a conductance-based model and a map-based model.

  20. Does functional redundancy stabilize fish communities?

    DEFF Research Database (Denmark)

    Rice, Jake; Daan, Niels; Gislason, Henrik

    2013-01-01

    in abundance or biomass could be accounted for by the Law of Large Numbers, providing no evidence that specific ecological processes or co-adaptations are necessary to produce this effect. This implies that successful conservation policies to maintain the resilience of a marine fish community could be based......Functional redundancy of species sharing a feeding strategy and/or maximum size has been hypothesized to contribute to increased resilience of marine fish communities (the “portfolio effect”). A consistent time-series of survey data of fish in the North Sea was used to examine if trophic functional...... groups or maximum length of species (Lmax) groups with larger numbers of species had lower coefficients of variation in abundance and biomass over time than did groupings with fewer species. Results supported this hypothesis. However, the stabilizing effect of numbers of species in a group on variation...

  1. Timing control by redundant inhibitory neuronal circuits

    International Nuclear Information System (INIS)

    Tristan, I.; Rulkov, N. F.; Huerta, R.; Rabinovich, M.

    2014-01-01

    Rhythms and timing control of sequential activity in the brain is fundamental to cognition and behavior. Although experimental and theoretical studies support the understanding that neuronal circuits are intrinsically capable of generating different time intervals, the dynamical origin of the phenomenon of functionally dependent timing control is still unclear. Here, we consider a new mechanism that is related to the multi-neuronal cooperative dynamics in inhibitory brain motifs consisting of a few clusters. It is shown that redundancy and diversity of neurons within each cluster enhances the sensitivity of the timing control with the level of neuronal excitation of the whole network. The generality of the mechanism is shown to work on two different neuronal models: a conductance-based model and a map-based model

  2. Headset Bluetooth and cell phone based continuous central body temperature measurement system.

    Science.gov (United States)

    Sanches, J Miguel; Pereira, Bruno; Paiva, Teresa

    2010-01-01

    The accurate measure of the central temperature is a very important physiologic indicator in several clinical applications, namely, in the characterization and diagnosis of sleep disorders. In this paper a simple system is described to continuously measure the body temperature at the ear. An electronic temperature sensor is coupled to the microphone of a common commercial auricular Bluetooth device that sends the temperature measurements to a mobile phone to which is paired. The measurements are stored at the mobile phone and periodically sent to a medical facility by email or SMS (short messaging service).

  3. Analysis and Design of Offset QPSK Using Redundant Filter Banks

    International Nuclear Information System (INIS)

    Fernandez-Vazquez, Alfonso; Jovanovic-Dolecek, Gordana

    2013-01-01

    This paper considers the analysis and design of OQPSK digital modulation. We first establish the discrete time formulation, which allows us to find the equivalent redundant filter banks. It is well known that redundant filter banks are related with redundant transformation of the Frame theory. According to the Frame theory, the redundant transformations and corresponding representations are not unique. In this way, we show that the solution to the pulse shaping problem is not unique. Then we use this property to minimize the effect of the channel noise in the reconstructed symbol stream. We evaluate the performance of the digital communication using numerical examples.

  4. Detection of sensor failures in nuclear plants using analytic redundancy

    International Nuclear Information System (INIS)

    Kitamura, M.

    1980-01-01

    A method for on-line, nonperturbative detection and identification of sensor failures in nuclear power plants was studied to determine its feasibility. This method is called analytic redundancy, or functional redundancy. Sensor failure has traditionally been detected by comparing multiple signals from redundant sensors, such as in two-out-of-three logic. In analytic redundancy, with the help of an assumed model of the physical system, the signals from a set of sensors are processed to reproduce the signals from all system sensors

  5. The measurement of stresses in prestressed concrete at elevated temperatures

    International Nuclear Information System (INIS)

    Dincmen, T.

    1978-03-01

    This report deals with the measurement of stresses in the prestressed concrete vessel at the research center Seibersdorf during the prestressing and the thermal stabilization period. The thermal stabilization was carried out at 120 0 C. (author)

  6. Lidar measurements of mesospheric temperature inversion at a low latitude

    Energy Technology Data Exchange (ETDEWEB)

    Siva Kumar, V.; Bhavani Kumar, Y.; Raghunath, K.; Rao, P.B. [National MST Radar Facility, Tirupati (India); Krishnaiah, M. [Sri Venkateswara Univ., Tirupati (India). Dept. of Physics; Mizutani, K.; Aoki, T.; Yasui, M.; Itabe, T. [Communication Research Lab., Tokyo (Japan)

    2001-08-01

    The Rayleigh lidar data collected on 119 nights from March 1998 to February 2000 were used to study the statistical characteristics of the low latitude mesospheric temperature inversion observed over Gadanki (13.5 N, 79.2 E), India. The occurrence frequency of the inversion showed semiannual variation with maxima in the equinoxes and minima in the summer and winter, which was quite different from that reported for the mid-latitudes. The peak of the inversion layer was found to be confined to the height range of 73 to 79 km with the maximum occurrence centered around 76 km, with a weak seasonal dependence that fits well to an annual cycle with a maximum in June and a minimum in December. The magnitude of the temperature deviation associated with the inversion was found to be as high as 32 K, with the most probable value occurring at about 20 K. Its seasonal dependence seems to follow an annual cycle with a maximum in April and a minimum in October. The observed characteristics of the inversion layer are compared with that of the mid-latitudes and discussed in light of the current understanding of the source mechanisms. (orig.)

  7. Analytical Redundancy Design for Aeroengine Sensor Fault Diagnostics Based on SROS-ELM

    Directory of Open Access Journals (Sweden)

    Jun Zhou

    2016-01-01

    Full Text Available Analytical redundancy technique is of great importance to guarantee the reliability and safety of aircraft engine system. In this paper, a machine learning based aeroengine sensor analytical redundancy technique is developed and verified through hardware-in-the-loop (HIL simulation. The modified online sequential extreme learning machine, selective updating regularized online sequential extreme learning machine (SROS-ELM, is employed to train the model online and estimate sensor measurements. It selectively updates the output weights of neural networks according to the prediction accuracy and the norm of output weight vector, tackles the problems of singularity and ill-posedness by regularization, and adopts a dual activation function in the hidden nodes combing neural and wavelet theory to enhance prediction capability. The experimental results verify the good generalization performance of SROS-ELM and show that the developed analytical redundancy technique for aeroengine sensor fault diagnosis based on SROS-ELM is effective and feasible.

  8. Statistical Redundancy Testing for Improved Gene Selection in Cancer Classification Using Microarray Data

    Directory of Open Access Journals (Sweden)

    J. Sunil Rao

    2007-01-01

    Full Text Available In gene selection for cancer classifi cation using microarray data, we define an eigenvalue-ratio statistic to measure a gene’s contribution to the joint discriminability when this gene is included into a set of genes. Based on this eigenvalueratio statistic, we define a novel hypothesis testing for gene statistical redundancy and propose two gene selection methods. Simulation studies illustrate the agreement between statistical redundancy testing and gene selection methods. Real data examples show the proposed gene selection methods can select a compact gene subset which can not only be used to build high quality cancer classifiers but also show biological relevance.

  9. [A method of temperature measurement for hot forging with surface oxide based on infrared spectroscopy].

    Science.gov (United States)

    Zhang, Yu-cun; Qi, Yan-de; Fu, Xian-bin

    2012-05-01

    High temperature large forging is covered with a thick oxide during forging. It leads to a big measurement data error. In this paper, a method of measuring temperature based on infrared spectroscopy is presented. It can effectively eliminate the influence of surface oxide on the measurement of temperature. The method can measure the surface temperature and emissivity of the oxide directly using the infrared spectrum. The infrared spectrum is radiated from surface oxide of forging. Then it can derive the real temperature of hot forging covered with the oxide using the heat exchange equation. In order to greatly restrain interference spectroscopy through included in the received infrared radiation spectrum, three interference filter system was proposed, and a group of optimal gap parameter values using spectral simulation were obtained. The precision of temperature measurement was improved. The experimental results show that the method can accurately measure the surface temperature of high temperature forging covered with oxide. It meets the requirements of measurement accuracy, and the temperature measurement method is feasible according to the experiment result.

  10. Measured Temperature Dependence of the cos-phi Conductance in Josephson Tunnel Junctions

    DEFF Research Database (Denmark)

    Sørensen, O. H.; Mygind, Jesper; Pedersen, Niels Falsig

    1977-01-01

    The temperature dependence of the cosϕ conductance in Sn-O-Sn Josephson tunnel junctions has been measured just below the critical temperature, Tc. From the resonant microwave response at the junction plasma frequency as the temperature is decreased from Tc it is deduced that the amplitude of the...

  11. Electrical measuring device for a high temperature reactor

    International Nuclear Information System (INIS)

    Elter, C.; Handel, H.; Schoening, J.; Schmitt, H.

    1982-01-01

    The device for measuring the low or high neutron flux during start-up or at load is accommodated in an armoured guide tube projecting into the floor. A gas-tight capsule is formed as the measuring column with outer dome with a lid solidly connected by a flange to the armoured tube situated on the side wall of the concrete reactor vessel, together with the armoured guide tube. Two shielding shutters prevent the passage of radiation through the armoured tube. (DG) [de

  12. The effect of different solar simulators on the measurement of short-circuit current temperature coefficients

    Science.gov (United States)

    Curtis, H. B.; Hart, R. E., Jr.

    1982-01-01

    Gallium arsenide solar cells are considered for several high temperature missions in space. Both near-Sun and concentrator missions could involve cell temperatures on the order of 200 C. Performance measurements of cells at elevated temperatures are usually made using simulated sunlight and a matched reference cell. Due to the change in bandgap with increasing temperature at portions of the spectrum where considerable simulated irradiance is present, there are significant differences in measured short circuit current at elevated temperatures among different simulators. To illustrate this, both experimental and theoretical data are presented for gallium arsenide cells.

  13. Identification of complex model thermal boundary conditions based on exterior temperature measurement

    International Nuclear Information System (INIS)

    Lu Jianming; Ouyang Guangyao; Zhang Ping; Rong Bojun

    2012-01-01

    Combining the advantages of the finite element software in temperature field analyzing with the multivariate function optimization arithmetic, a feasibility method based on the exterior temperature was proposed to get the thermal boundary conditions, which was required in temperature field analyzing. The thermal boundary conditions can be obtained only by some temperature measurement values. Taking the identification of the convection heat transfer coefficient of a high power density diesel engine cylinder head as an example, the calculation result shows that when the temperature measurement error was less than 0.5℃, the maximum relative error was less than 2%. It is shown that the new method was feasible (authors)

  14. Pulse pileup effects of plasma electron temperature measurements by soft x-ray energy analysis

    International Nuclear Information System (INIS)

    Dyer, G.R.; Neilson, G.H.; Kelley, G.G.

    1978-10-01

    The electron temperature of hot plasmas is conveniently derived from bremsstrahlung spectra obtained by pulse-height analysis using a lithium-compensated silicon detector. Time-resolved temperature measurements require high counting rates, with ultimate rate limited by pulse pileup. To evaluate this limit, spectral distortion due to pileup and consequent effects on temperature determination are investigated. Expressions for distorted spectra are derived as functions of Maxwellian temperature and pileup fraction for both square and triangular pulse shapes. A comparison of temperatures obtained from distorted spectra with actual values indicates that measurements with less than 10% error can be made in the absence of line radiation, even from spectra containing 40% pileup

  15. Comparison of auricular and rectal temperature measurement in normothermic, hypothermic, and hyperthermic dogs.

    Science.gov (United States)

    Konietschke, U; Kruse, B D; Müller, R; Stockhaus, C; Hartmann, K; Wehner, A

    2014-01-01

    Measurement of rectal temperature is the most common method and considered gold standard for obtaining body temperature in dogs. So far, no study has been performed comparing agreement between rectal and auricular measurements in a large case series. The purpose of the study was to assess agreement between rectal and auricular temperature measurement in normothermic, hypothermic, and hyperthermic dogs with consideration of different environmental conditions and ear conformations. Reference values for both methods were established using 62 healthy dogs. Three hundred dogs with various diseases (220 normothermic, 32 hypothermic, 48 hyperthermic) were enrolled in this prospective study. Rectal temperature was compared to auricular temperature and differences in agreement with regard to environmental temperature, relative humidity, and different ear conformations (pendulous versus prick ears) were evaluated using Pearson's correlation coefficient and Bland-Altman analysis. Correlation between rec- tal and auricular temperature was significant (r: 0.892; p  temperature did not. Variation between the two methods of measuring body temperature was clinically unacceptable. Although measurement of auricular temperature is fast, simple, and well tolerated, this method provides a clinically unacceptable difference to the rectal measurement.

  16. Optical sensor for measuring humidity, strain and temperature

    DEFF Research Database (Denmark)

    2015-01-01

    The present invention relates to an optical sensor (100) adapted to measure at least three physical parameters, said optical sensor comprising a polymer-based optical waveguide structure comprising a first Bragg grating structure (101) being adapted to provide information about a first, a second...

  17. High-temperature rate constant measurements for OH+xylenes

    KAUST Repository

    Elwardani, Ahmed Elsaid; Badra, Jihad; Farooq, Aamir

    2015-01-01

    The overall rate constants for the reactions of hydroxyl (OH) radicals with o-xylene (k 1), m-xylene (k 2), and p-xylene (k 3) were measured behind reflected shock waves over 890-1406K at pressures of 1.3-1.8atm using OH laser absorption near 306

  18. Magnetic Levitation Force Measurement System at Any Low Temperatures From 20 K To 300 K

    Science.gov (United States)

    Celik, Sukru; Guner, S. Baris; Coskun, Elvan

    2015-03-01

    Most of the magnetic levitation force measurements in previous studies were performed at liquid nitrogen temperatures. For the levitation force of MgB2 and iron based superconducting samples, magnetic levitation force measurement system is needed. In this study, magnetic levitation force measurement system was designed. In this system, beside vertical force versus vertical motion, lateral and vertical force versus lateral motion measurements, the vertical force versus temperature at the fixed distance between permanent magnet PM - superconducting sample SS and the vertical force versus time measurements were performed at any temperatures from 20 K to 300 K. Thanks to these measurements, the temperature dependence, time dependence, and the distance (magnetic field) and temperature dependences of SS can be investigated. On the other hand, the magnetic stiffness MS measurements can be performed in this system. Using the measurement of MS at different temperature in the range, MS dependence on temperature can be investigated. These measurements at any temperatures in the range help to the superconductivity properties to be characterized. This work was supported by TUBTAK-the Scientific and technological research council of Turkey under project of MFAG - 110T622. This system was applied to the Turkish patent institute with the Application Number of 2013/13638 on 22/11/2013.

  19. A method enabling simultaneous pressure and temperature measurement using a single piezoresistive MEMS pressure sensor

    International Nuclear Information System (INIS)

    Frantlović, Miloš; Stanković, Srđan; Jokić, Ivana; Lazić, Žarko; Smiljanić, Milče; Obradov, Marko; Vukelić, Branko; Jakšić, Zoran

    2016-01-01

    In this paper we present a high-performance, simple and low-cost method for simultaneous measurement of pressure and temperature using a single piezoresistive MEMS pressure sensor. The proposed measurement method utilizes the parasitic temperature sensitivity of the sensing element for both pressure measurement correction and temperature measurement. A parametric mathematical model of the sensor was established and its parameters were calculated using the obtained characterization data. Based on the model, a real-time sensor correction for both pressure and temperature measurements was implemented in a target measurement system. The proposed method was verified experimentally on a group of typical industrial-grade piezoresistive sensors. The obtained results indicate that the method enables the pressure measurement performance to exceed that of typical digital industrial pressure transmitters, achieving at the same time the temperature measurement performance comparable to industrial-grade platinum resistance temperature sensors. The presented work is directly applicable in industrial instrumentation, where it can add temperature measurement capability to the existing pressure measurement instruments, requiring little or no additional hardware, and without adverse effects on pressure measurement performance. (paper)

  20. Telemetric measurement of body core temperature in exercising unconditioned Labrador retrievers.

    Science.gov (United States)

    Angle, T Craig; Gillette, Robert L

    2011-04-01

    This project evaluated the use of an ingestible temperature sensor to measure body core temperature (Tc) in exercising dogs. Twenty-five healthy, unconditioned Labrador retrievers participated in an outdoor 3.5-km run, completed in 20 min on a level, 400-m grass track. Core temperature was measured continuously with a telemetric monitoring system before, during, and after the run. Data were successfully collected with no missing data points during the exercise. Core temperature elevated in the dogs from 38.7 ± 0.3°C at pre-exercise to 40.4 ± 0.6°C post-exercise. While rectal temperatures are still the standard of measurement, telemetric core temperature monitors may offer an easier and more comfortable means of sampling core temperature with minimal human and mechanical interference with the exercising dog.