Dynamic Calibration Method Research Articles

Dynamic calibration method of high-pressure transducer based on quasi-δ function excitation source

This paper presents a dynamic calibration method of frequency response characteristics of high-pressure sensor. In this method, the pressure sensor was under high hydrostatic pressure in advance, then use the bullet impacted Hopkinson bar and generated quasi-δ function signal with small amplitude, which excited the sensor being calibrated. The excitation signal of sensor are collected, at the same time, output signal of the sensor are collected, and at last, the collected data are processed according to calibration principle and calculated the frequency response of the sensor being calibrated. This calibration method realized dynamic calibration of high pressure sensor under actual working pressure; it can realize the low limit frequency of the calibrated frequency range strictly reaches to zero frequency. This method can also be applied to acceleration sensor, transient high-temperature sensor, and other types of sensors. In this paper, the calibration principle of quasi-δ function dynamic calibration method is introduced. The relationship among pulse width of excitation signal, frequency range that can be calibrated and calibration precision is analyzed. The experimental results are also shown.

The Miniature Internal Electronic Pressure Gauge and Dynamic Calibration Method

In order to measure the chamber pressure of small caliber artilleries, a miniature internal electronic pressure gauge is designed, which adopted low power technology and miniaturization technology and storage testing technology. The working principle and the hardware design process of the gauge are described. The gauge is an intelligent pressure sensor system. The gauge is powered by battery, low power consumption, easy handling, high precision, high accuracy, and high reliability and can be reused. The gauge is used to test weapon chamber pressure which caliber greater than 57mm Dynamic calibration method based on the testing environment is proposed, the chamber pressure generator is developed; it can simulate the environments of artillery firing. Dynamic calibration system is established, the whole structure and working principle of the system is introduced. The necessity of environmental factors calibration is analyzed. The test data show that the static sensitivity coefficients and dynamic sensitivity coefficients are different. The data of the pressure gauge that have been calibrated have better stability and high confidence level. Accurate and reliable test data provides the important basis for assessing artillery, charge structure and ballistic performance.

The Effect on Hemolysis of the Raceway Profile of Roller Pumps Used in Cardiopulmonary Bypass

This study aims at the influence on hemolysis of the differences between the maximum and minimum amplitudes of pressure in the outlet of three roller pump models adjusted by dynamic calibration method. Tests were performed with silicone tubes (½ × (3)/(16) inches) in fluid analogous to blood and fresh bovine blood from slaughterhouse. Tests with analogous solution to blood were performed varying the dynamic calibration pressure between 78 and 500 mm Hg. Tests with fresh bovine blood were performed with the three pumps simultaneously, and pressure differences and free hemoglobin in the plasma were measured during 360 minutes. Tests with both analogous solution to blood and fresh bovine blood showed differences of mean pressures of pump 2 related to pumps 1 and 3 (p < 0.01). The different models of roller pumps analyzed presented differences in pressure amplitudes (p < 0.01) and hemolysis (p < 0.01) adjusted for the same dynamic calibration pressure. Raceway profile of pump 2 resulted in smaller pressure amplitude, implying lower hemolysis rate compared with pumps 1 and 3.

An Analysis on a Dynamic Amplifier and Calibration Methods for a Pseudo-Differential Dynamic Comparator

This paper analyzes a pseudo-differential dynamic comparator with a dynamic pre-amplifier. The transient gain of a dynamic pre-amplifier is derived and applied to equations of the thermal noise and the regeneration time of a comparator. This analysis enhances understanding of the roles of transistor's parameters in pre-amplifier's gain. Based on the calculated gain, two calibration methods are also analyzed. One is calibration of a load capacitance and the other is calibration of a bypass current. The analysis helps designers' estimation for the accuracy of calibration, dead-zone of a comparator with a calibration circuit, and the influence of PVT variation. The analyzed comparator uses 90-nm CMOS technology as an example and each estimation is compared with simulation results.

Os perfusionistas Brasileiros e o ajuste do rolete arterial: comparação entre a calibração estática e dinâmica

Roller pumps play an important role in extracorporeal circulation. However, occlusion of the rollers should be adequately performed and this can be adjusted mainly by two methods: static and dynamic.To investigate how the Brazilian perfusionists adjust arterial roller pumps in their services and evaluate the application of a Device to Assist Calibration (DAC) that facilitates roller adjustment by the dynamic calibration method.We installed a roller pump with accessories to perform adjustment by drop rate (static calibration) and dynamic calibration methods during the XXVIII Brazilian Congress of Extracorporeal Circulation. Perfusionists were asked to adjust the roller pump according to the procedure they usually do in their service. After each adjustment pressure was measured by dynamic calibration method with DAC. The research was approved by the Research Ethics Committee of UNICAMP, Nº 1144/2010.There were 56 perfusionists in this study. Pressure average of 56 measurements of dynamic calibration was 434 ± 214 mmHg; 76% of measurements were within the recommended range for the use of the dynamic calibration method (between 150 and 500 mmHg).Brazilian perfusionists tend to adjust roller pumps with less occlusive settings. The amplitudes of the dynamic calibration pressure tend to be smaller for more experienced perfusionists because their skills increase with time. The device can be used by the perfusionist to adjust roller pumps with greater accuracy and mainly repeatability in few minutes.

Limitations on dynamic excess carrier lifetime calibration methods

ABSTRACTComparison of minority carrier lifetime measurements carried out in transient mode with measurements performed under steady‐state conditions allows determination of the calibration constants needed in non‐transient measurements. In this letter, we point out practical scenarios in which the assumptions underlying this approach break down, resulting in significant experimental errors. Specific examples for crystalline silicon wafers will be discussed to provide some guidelines on practical limitations of this calibration approach. Large errors are possible for wafers with high surface recombination velocity as might be the case for incoming wafers for a solar cell production line. Copyright © 2011 John Wiley &amp; Sons, Ltd.

Application of the method of dynamic calibration for IMS stations in regions with lower seismic activity

The Method of Dynamic Calibration (MDC) of stations of the International Monitoring System (IMS) was developed for calibrating regions where no underground nuclear explosions were carried out, with the purpose of providing conditions for implementation of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) in nontrivial cases. Initially, the MDC had been presented in [Kedrov, 2001; Kedrov et al., 2001; Kedrov O.K. and Kedrov E.O., 2003] and then considered in detail in [Kedrov et al., 2008]. The core of MDC relates to adapting diagnostic parameters for the identification of underground nuclear explosions (UNE) and earthquakes elaborated for the region of Eurasia, taken as a basic region (BR), for other researched regions that differ from BR in the character of the attenuation of seismic waves. The unique characteristic of this method lies in the fact that calibration of diagnostic parameters with the help of attenuation coefficients bΔ at varied source-station traces is implemented using only natural seismicity data within the limits of an explored region and does not require special underground chemical explosions. The MDC algorithm is implemented in the research program ”Kalibr”, which was tested by using the experimental data from Eurasia region. It is shown in this work that MDC can be used for calibration of regions where a very low level of natural seismicity is observed. According to the results of the calibration of diagnostic parameters at IMS stations in several regions of North America, Africa, and Asia, the approximate classification of propagation conditions for seismic signals at source-station traces in platform and tectonically active regions is made. The results for the development of two research programs, “Spektr” and “Signal”, are presented; this software is intended for automation of calculation procedures for spectral diagnostic parameters of UNEs’ and earthquakes’ identification by amplitude spectra of P waves and by the maximal amplitudes of P, S, and LR signals. The application of these programs allowed us to accelerate the whole calibration procedure for a particular source-station trace using the ”Kalibr” program.

저 레이놀즈 수 영역에서 날갯짓 비행체 공력 모델의 실험적 검증

In this study, an efficient ornithopter aerodynamic model, which is applicable to ornithopter wing design considering fluid-structure interaction or ornithopter flight dynamics and control simulation, was proposed and experimentally validated through the wind tunnel experiments. Due to the ornithopter aerodynamics governed by unsteady low Reynolds number flow, an experimental device was specially designed and developed. A part of the experimental device, 2-axis loadcell, was situated in the non-inertial frame; the dynamic calibration method was established to compensate the inertial load for pure aerodynamic load measurements. The characteristics of proposed aerodynamic model were compared with the experimental data in terms of mean and root-mean-square values of lift and drag coefficients with respect to the flow speed, flapping frequency, and fixed angle of attack.

Visualização de refluxo em aspirador de sangue e reservatório de cardiotomia usados em circulação extracorpórea

One of the major damage caused by occlusion in roller pumps is hemolysis. Comparative studies between roller pump with adjustments non occlusive and centrifugal pumps have been made in recent decades in an attempt to develop new products and adjustments that cause fewer traumas to the figurative elements of blood. Usually the roller pumps are adjusted by the static method due to concern variables flow that can occur with non-occlusive settings. Excessive slack in the rollers provoke back flow and can provides errors in the calculation of flow by the rotation of the pump, according to the devices added to the circuit and the systemic resistance of the patient. The objective of this study is to evaluate the back flow caused by two types of roller pumps in blood aspirator and cardiotomy reservoir. Back flow visualization was performed in blood aspirator and cardiotomy reservoir. It was tested two different models of roller pumps, adjusted by drop rate and dynamic calibration. The tests were conducted with silicone tubes of 3/8 x 1/16 e 1/2 x 3/32 inches in diameter in water and solution similar to blood. We recorded back flow visually in blood aspirator and in cardiotomy reservoir with their measure of values. The pumps had differences in refluxes measured adjusted by the dynamic calibration method. Pump#2 presents back flow adjusted fully occluded. The back flow measured in two models of pump present differences (P <0.008). The results indicate differences in its characteristics caused by the process of manufacturing, design or possible wear. Non-occlusive adjustments may cause variations in flow with the increase of resistance added to the circuit, with difficulty to fix the flow by increasing the rotation.

Improvement of the accuracy of friction coefficient determination with Amsler-type friction machines

The error of friction coefficient determination with Amsler-type machines depends strongly on the friction losses in the machine’s spindle unit. It is shown theoretically that the error is inversely proportional to the product of the lower roller diameter times the friction coefficient to be measured and directly proportional to the friction coefficient of the rolling bearings employed; the error can reach 100% or more. A method of static and dynamic torque sensor calibration is developed to ensure friction coefficient measurement accuracy within ±2%.

Toward Establishing Dynamic Calibration Method for Force Transducers

In this paper, ways to establish dynamic calibration methods for force transducers are discussed. Three methods of evaluating the dynamic response of force transducers against typical varying forces, such as impact, oscillation, and step forces, are described in this paper. In all the three methods, the inertial force of a mass is used as the known dynamic force, and this reference force is applied to a force transducer under test. The inertial force is highly accurately measured as the product of mass and acceleration. An aerostatic linear bearing is used to obtain linear motion with sufficiently small friction acting on the mass (i.e., the moving part of the bearing). The present status and the future prospects of attempts toward establishing dynamic calibration methods for force transducers are discussed in detail.

Toward dynamic force calibration

Ways of establishing dynamic calibration methods are discussed. Three methods for evaluating the dynamic response of force transducers against varying force are described. In all methods, the inertial force of a mass is used as the known dynamic force, and this reference force is applied to a force transducer under test. The inertial force is measured highly accurately as the product of the mass and the acceleration. An aerostatic linear bearing is used to obtain linear motion with sufficiently small friction acting on the mass (i.e., the moving part of the bearing). Three experimental setups were built for the dynamic calibration against an impact force, an oscillation force and a step force. The present status and the future prospects of dynamic force calibration are discussed.

117 波動伝播モデルによる動的ロードセルの問題点の解明

The issues in dynamic load cell have been investigated based on the wave propagation model. It was revealed that the output value of the cell varies depending upon dynamic rigidities, i.e. boundary conditions, of the set up position. For the controversy about dynamic calibration method for load cells, it was disclosed by the experiments that static method of calibration is satisfactory for the column type load cells which usually employed in the measurement of dynamic loads.

Application of the dynamic calibration method to international monitoring system stations in Central Asia using natural seismicity data

The dynamic calibration method (DCM), using natural seismicity data and initially elaborated in [Kedrov, 2001; Kedrov et al., 2001; Kedrov and Kedrov, 2003], is applied to International Monitoring System (IMS) stations in Central Asia. The algorithm of the method is refined and a program is designed for calibrating diagnostic parameters (discriminants) that characterize a seismic source on the source-station traces. The DCM calibration of stations in relation to the region under study is performed by the choice of attenuation coefficients that adapt the diagnostic parameters to the conditions in a reference region. In this method, the stable Eurasia region is used as the latter. The calibration used numerical data samples taken from the archive of the International Data Centre (IDC) for the IMS stations MKAR, BVAR, EIL, ASF, and CMAR. In this paper, we used discriminants in the spectral and time domains that have the form $$ D_i = X_i - a_m m_b - b_\Delta \log \Delta $$ and are independent of the magnitude mb and the epicentral distance Δ; these discriminants were elaborated in [Kedrov et al., 1990; Kedrov and Lyuke, 1999] on the basis of a method used for identification of events at regional distances in Eurasia. Prerequisites of the DCM are the assumptions that the coefficient am is regionindependent and the coefficient bΔ depends only on the geotectonic characteristics of the medium and does not depend on the source type. Thus, bΔ can be evaluated only from a sample of earthquakes in the region studied; it is used for adapting the discriminants D(Xi) in the region studied to the reference region. The algorithm is constructed in such a way that corrected values of D(Xi) are calculated from the found values of the calibration coefficients bΔ, after which natural events in the region under study are selected by filtering. Empirical estimates of the filtering efficiency as a function of a station vary in a range of 95–100%. The DCM was independently tested using records obtained at the IRIS (Incorporated Research Institutions for Seismology) stations BRVK and MAKZ from explosions detonated in India on May 11, 1998, and Pakistan on May 28, 1998; these stations are similar in location and recording instrumentation characteristics to the IMS stations BVAR and MKAR. This test resulted in correct recognition of the source type and thereby directly confirmed the validity of the proposed calibration method of stations with the use of natural seismicity data. It is shown that the calibration coefficients bΔ for traces similar in the conditions of signal propagation (e.g., the traces from Iran to the stations EIL and ASF) are comparable for nearly all diagnostic parameters. We arrive at the conclusion that the method of dynamic calibration of stations using natural seismicity data in a region where no explosions were detonated can be significant for a rapid and inexpensive calibration of IMS stations. The DCM can also be used for recognition of industrial chemical explosions that are sometimes erroneously classified in regional catalogs as earthquakes.

A Dynamic Calibration Method for Crusher Gauges Based on Material Testing

AbstractThis paper presents a new dynamic calibration method for crusher pressure gauges used in artillery test firings. The calibration method is based on the measurement of the plastic deformation behavior of the crusher elements in the laboratory completely isolated from test firings and measurements by reference pressure transducers. The validity of the calibration model developed is verified by comparison with the pressure records measured in artillery test firings. It was found that the calibration method developed is also suitable for the high load levels and strain rates present in tank firings.

Development of algorithm to measure temperatures of liquid/gas phases using micro-thermocouple and experiment with optical chopper

This paper introduces the algorithm developed to measure the local temperature of phases in the non-isothermal two-phase flow by using micro-thermocouple, which was verified using an optical chopper and a laser. The micro-thermocouple, whose outer diameter of which is 12.7 μm, consists of a couple of alumel-chromel wire (K-type). The hot-junction, a part of the sensor used to for measuring temperature, is fabricated by hot-wire shapes. The response time of the micro-thermocouple, which was measured by dynamic calibration method, was several milliseconds in flow condition. An algorithm to calculate the temperature of each, which is based on the response time of micro-thermocouple and the exponential regression method, was developed. And the developed algorithm was verified through experiments using an optical chopper and a laser.

Recent improvements of the broadband FMCW reflectometry system for density profile measurements on ASDEX Upgrade

The broadband FMCW reflectometry system on ASDEX Upgrade has had significant improvements extending its measuring capabilities both on high and low density plasmas: (i) the upgrade of the W band to probe electron densities up to 12.4×1019 m−3 with O mode, (ii) Q and V frequency bands operating in X mode to probe the edge plasma and to provide information for O-mode profile initialization, and (iii) a new dynamic frequency calibration method to take into account all existing delays in the hyperabrupt varactor-tuned oscillator (HTO) tuning port and driver electronics. These improvements are particularly important to measure accurately the edge pedestal region of high density ITER relevant discharges. Density profiles obtained in high density discharges are presented and compared with results from both Li-beam and Thomson scattering diagnostics.

Respirometric 13C flux analysis, Part I: Design, construction and validation of a novel multiple reactor system using on-line membrane inlet mass spectrometry

A novel method for 13C flux analysis based on on-line CO 2 labeling measurements is presented. This so-called respirometric 13C flux analysis requires multiple parallel 13C labeling experiments using differently labeled tracer substrates. In Part I of the work, a membrane-inlet mass spectrometry-based measurement system with 6 parallel reactors with each 12 ml liquid volume and associated experimental and computational methods for the respirometric 13C data acquisition and evaluation are described. Signal dynamics after switching between membrane probes follow exactly first-order allowing extrapolation to steady state. Each measurement cycle involving 3 reactors takes about 2 min. After development of a dynamic calibration method, the suitability and reliability of the analysis was examined with a lysine-producing mutant of Corynebacterium glutamicum using [1- 13C 1], [6- 13C 1], [1,6- 13C 2] glucose. Specific rates of oxygen uptake and CO 2 production were estimated with an error less than ±0.3 mmol g −1 h −1 and had ±3% to ±10% deviations between parallel reactors which is primarily caused by inaccuracies in initial biomass concentration. The respiratory quotient could be determined with an uncertainty less than ±0.02 and varied only ±3% between reactors. Fractional labeling of CO 2 was estimated with much higher precision of about ±0.001 to ±0.005. The detailed statistical analysis suggested that these data should be of sufficient quality to allow physiological interpretation and metabolic flux estimation. The obtained data were applied for the respirometric 13C metabolic flux analysis in Part II.

831 複数台カメラによる広領域場の自動追跡(G15-1 画像応用技術・移動ロボット,G15 ロボティクス・メカトロニクス)

This paper proposes a tracking system that is equipped with active vision agents communicating with each other. We set up them at any number of places to realize an optimized tracking in a wide 3-D field. We present a dynamic calibration method, which enables us to calibrate the extrinsic parameters of cameras automatically and simultaneously. Each camera traces a common object and detects corresponding points that are used to determine extrinsic parameters. The calibrated cameras use their pan, tilt and zoom facilities and cooperatively estimate the positions of a moving object in a 3-D field.

High temperature displacement sensor

A high temperature displacement sensor based on the principle of eddy-current is investigated. A new temperature compensation technique by using eddy-current effect is presented to satisfy the special requirement at high temperature up to 550℃. The experiment shows that the temperature compensation technique leads to good temperature stability for the sensors. The variation of the sensitivity as well as the temperature drift of the sensor with temperature compensation technique is only about 7.4% and 90～350 mV at 550℃ compared with that at room temperature, and that of the sensor without temperature compensation technique is about 31.2% and 2～3 V at 550℃ compared with that at room temperature. A new dynamic calibration method for the eddy-current displacement sensor is presented, which is very easy to be realized especially in high frequency and at high temperatures. The high temperature displacement sensors developed are successfully used at temperature up to 550℃ in a magnetic bearing system for more than 100 h.