Technique For Simultaneous Measurement Research Articles

Simultaneous Two-Parameter Sensing Using a Single Tilted Moiré Fiber Bragg Grating With Discrete Wavelet Transform Technique

We propose and demonstrate using a single tilted moiré fiber Bragg grating (TMFBG) with the discrete wavelet transform (DWT) technique for simultaneous measurement of refractive index (RI) and temperature. The particular feature of interest is that the spectrum consists of two separate parts associated with the phase-shifted main Bragg mode and discrete cladding modes, and that they have distinctive responses to RI and temperature. Our results showed that the cladding modes are, while the Bragg mode is not, sensitive to the surrounding RI. On the other hand, both the Bragg and cladding modes have the same linear temperature response. Hence, temperature can be obtained from the Bragg mode shift, and RI from the differential shift between the Bragg and cladding modes. In our experiment, the measured shifts of the Bragg and cladding modes can be unambiguously determined by applying the DWT technique. Thus, simultaneous two-parameter sensing using only a single TMFBG sensor is realized.

Dynamic monitoring of refractive index change through photoactive resins

Objectives The change in optical characteristics through the bulk of curing photopolymers is not fully understood. Photopolymerization processes are accompanied by photoinitiator absorption, density changes and volumetric shrinkage, which alter optical properties and affects curing efficiency through depth. Methods This investigation demonstrates the use of a novel low coherence interferometry technique for simultaneous measurement of optical (refractive index) and physical (shrinkage) properties throughout curing of photoactive monomers containing various concentrations of bisphenol-A-diglycidyl ether dimethacrylate and triethylene glycol dimethacrylate. Results Reliability of the interferometry technique was compared with an Abbé refractometer and showed a significant linear regression relationship ( p < 0.001; adjusted R 2 > 0.99) for both uncured and cured resins. The extent and rate of refractive index change and magnitude of shrinkage strain was dependent upon monomer formulation. Significance The development of this interferometry technique provides a powerful non-invasive tool that will be useful for improving light transmission through photoactive resins and filled resin composites by precise control of optical properties through material bulk.

Simultaneous displacement and angular drift measurement based on defocus grating

We propose and demonstrate a displacement and angular drift simultaneous measurement technique based on a defocus grating. The displacement and angular drift of the incident beam can be detected by monitoring the movements of +/-1 diffraction order spots of the defocus grating. The relationship between drift of the incident beam and movements of +/-1 diffraction order spots is studied in detail. Compared with other methods, this technique eliminates the requirement of two or more detecting systems for measuring displacement and angular drift simultaneously. The proof-of-principle experiment shows that the root-mean-square errors of displacement and angular drift measurements are less than 0.5 microm and 0.84 microrad, respectively.

Turbulence Modulations in the Boundary Layer of a Horizontal Particle-Laden Channel Flow

Turbulence modulations are experimentally investigated using particle image velocimetry (PIV) in the lower boundary layer of a fully developed horizontal channel flow. A simultaneous two-phase PIV measurement technique is adopted to acquire the turbulent statistics quantities and to examine the coherent structures in the near-wall region. Polythene beads with diameters of 60 μm are used as dispersed phases, and the PIV measurements have been performed at three mass loadings varying from 2.5 × 10−4 to 5 × 10−3. All the experiments are performed at a wall shear Reynolds number of Reτ = 430. The results show that the presence of the particles suppresses the coherent structures, with shorter streamwise extent of the quasistreamwise structures, and then, the wall-normal velocity fluctuations and shear Reynolds stresses are both decreased in the near-core region. In addition, as a result of the particle wake, the turbulence intensity and shear Reynolds stress both increase in the vicinity of the wall. Due to the drag effects of the particles on the gas, the streamwise velocity gradients decrease in the outer region and increase in the viscous sublayer, meanwhile the thickness of the viscous sublayer also decreases. These results cause the peak values of the streamwise velocity fluctuations adjacent to the wall to increase, and the peak positions shift to the wall. This is the reason for decreasing the near-wall region and increasing the near-core region of the streamwise velocity fluctuations in appearance.

A novel method for simultaneous measurement of doped optical fiber parameters

Simultaneous measurement technique of evaluating the doped optical fibers (DOF) parameters is a suitable scheme for DOF production industries. In this paper, we introduce a novel technique to characterize simultaneously the main parameters of DOF such as absorption and emission cross-sections (ACS, ECS), background loss coefficient (BLC), and low dopant concentration using the gain equation of DOFs. We used this new method to determine the ACS, ECS, BLC in a standard sample of Al-P-Erbium doped optical fiber. The results have been analyzed and compared with other reports.

A novel C6-phenyl liquid chromatographic technique for rapid and simultaneous measurements of urinary cotinine and nicotine

A simple and rapid liquid chromatographic assay using diode array detection for simultaneous measurements of urinary concentrations of cotinine and nicotine was described. Each urine sample in a volume of 100 μL was extracted with 500 μL of dichloroethane at 60 °C for 5 min. 20 μL of the dried and reconstituted extract was eluted at 1 mL min−1 with a mobile phase at pH 7.6. The urinary cotinine, nicotine and internal standard (indole-3-acetamide) were separated from matrix interferences within 4.2 min on a C6-phenyl column maintained at 50 °C. The calibration curve was linear from 10 to 5000 μg L−1 for cotinine, and from 20 to 7500 μg L−1 for nicotine. The recovery rates of spiked concentrations were close to or about 100% and reproducibility generally greater than 90%. It was observed that the extraction yield of nicotine was very much affected by the extraction temperature. Among various extraction solvents evaluated, dichloroethane offered the highest yield, especially for nicotine. Thus, the urinary nicotine levels determined were generally higher than those reported earlier. This method was used on urine samples from 245 subjects, which included 188 non-smokers, 17 light smokers and 40 heavy smokers. The mean values of cotinine and nicotine were 50 and 96 μg g−1 creatinine among non-smokers, 771 and 679 μg g−1 creatinine among light smokers, and 1422 and 1104 μg g−1 creatinine among heavy smokers.

Spinal Cord Injury Blunted Effects of Endothelin-1 on Ca2+ Transients and Calcium Current in Isolated Rat Cardiomyocytes

Plasma endothelin-1 (ET-1) levels are elevated in spinal cord injury (SCI), and ET-1 may be involved in the pathophysiology of this condition. However, its effects on contractile function of the heart of SCI rats are still unknown. To define more clearly the possible role of ET-1 following SCI, we investigated the effect of ET-1 on the contraction, calcium transients and L-type calcium current (I(Ca,L)) in the cardiomyocytes of control and SCI rats. Sixteen Sprague-Dawley male rats aged 80-100 days and weighing 250-350 g were randomized into control and SCI groups. Fourteen days following compression injury to the spinal cord, effects of ET-1 on the contraction, calcium transients and I(Ca,L) were studied in the cardiomyocytes of control and SCI rats by the technique of simultaneous measurement of intracellular Ca(2+) and contraction and by whole-cell configuration of the patch-clamp technique. In myocytes from control rats, ET-1 significantly increased contraction, the magnitude of Ca(2+) transients and the peak amplitude of I(Ca,L). However, ET-1 had little effect on the amplitude of contraction, calcium transients and I(Ca,L). in myocytes from SCI rats. These results suggest that the positive inotropic effects of ET-1 on control myocardial contraction may be altered in pathological states such as SCI.

J0503-2-2 光電プローブによる液滴の濃度,速度,径の同時計測法の開発([J0503-2]多次元計測技術の展開と応用(2))

J0503-2-2 光電プローブによる液滴の濃度,速度,径の同時計測法の開発([J0503-2]多次元計測技術の展開と応用(2))

1222 2色LIF・PIVによる温度場・速度場の同時計測法の開発とノンペネトレイティブ対流への応用(OS6-4 熱流体の可視化と計測4,オーガナイズドセッション:6)

1222 2色LIF・PIVによる温度場・速度場の同時計測法の開発とノンペネトレイティブ対流への応用(OS6-4 熱流体の可視化と計測4,オーガナイズドセッション:6)

Comparative PD pulse burst characteristics of transformer type natural and synthetic ester fluids and mineral oils

The partial discharge (PD) pulse burst behavior in natural and synthetic organic ester fluids and mineral oils of the type used in transformers has been examined, using simultaneous wide and narrow band measurement techniques. This permitted the determination and comparison of both the overall charge transfer of the PD pulse as well as that of the discrete PD pulses comprising the PD pulse burst in the evaluated dielectric fluids.

An Innovative Technique for Simultaneous Measurement of Three-Dimensional Kinematics and Induced Flow of a Swimming Fish

ABSTRACTIn this work, we introduced an innovative technique that enables simultaneous measurement of the 3D kinematics and 2D–3 Components fluid velocities of the induced flow of a swimming fish, which greatly advanced the experimental technique for research in fish biomechanics. This technique was theoretically based on the combined use of new reconstruction formulas of position and the calibration polynomials of stereo-DPIV, employing only two cameras in the imaging system. Both kinematic and hydrodynamic characteristics of a fish executing three-dimensional and complicated locomotion are readily and accurately revealed. Measuring simultaneously 3D kinematics and hydrodynamics is significantly important for an accurate investigation of fish biomechanics because fish motions are three-dimensional. We demonstrate results of 3D kinematics and fluid velocity fields measured in the wake of a maneuvering pectoral fin of a fish, which proves the effectiveness and usefulness of this technique. The application of this technique is extendable to biomechanics research concerning locomotion of both swimming and flying animals.

Development of Capillary Electrophoresis Technique for Simultaneous Measurement of Amlodipine and Atorvastatin from Their Combination Drug Formulations

A simple, accurate, precise, and sensitive capillary electrophoresis (CE) technique coupled to a diode array detector (DAD) has been developed for the separation and simultaneous determination of amlodipine (AM) and atorvastatin (AT) from their combination formulations. The proposed method utilized fused silica capillary (50 cm × 75 µm ID) and background electrolyte (BGE) composed of phosphate buffer (pH 6.5, 25 mM)-methanol, (80:20, v/v). The separation was achieved at 15 KV applied voltage and 25°C. Losartan was chosen as the internal standard to guarantee a high level of quantitative performance. The two drugs were subjected to thermal, photolytic, hydrolytic, and oxidative stress conditions and the stressed samples were analyzed by the proposed method. The method has shown adequate separation for AM and AT from its main degradation products (UK-55-410) & (PD 0162910-00), respectively, which demonstrated the specificity of the assay. The described method was linear over the range of 1 – 50 µg/mL (r = 0.9998) for both drugs (2.4 × 10−6 − 1.2 × 10−4 M for AM and 1.8 × 10−6 −8.6 × 10−5 M for AT). Intra- and inter-day RSD (n = 6) was ≤2.2%. The limits of detection for AM and AT were 0.5 µg/mL. The percentage recoveries (n = 6) of the two drugs from their tablet formulations were 99.97 ± 1.84 and 100.96 ± 1.12, respectively. Degradation products produced as a result of stress studies did not interfere with the detection of AM and AT and the assay can thus be considered stability indicating.

Experimental technique for simultaneous measurement of absorption-, emission cross-sections, and background loss coefficient in doped optical fibers

We report a new simple technique for the simultaneous measurements of absorption-, emission cross-sections, background loss coefficient, and dopant density of doped optical fibers with low dopant concentration. Using our proposed technique, the experimental characterization of a sample Ge–Er-doped optical fiber is presented, and the results are analyzed and compared with other reports. This technique is suitable for production line of doped optical fibers.

Breakdown mechanism in C&lt;sub&gt;3&lt;.sub&gt;F&lt;sub&gt;8&lt;/sub&gt;/CO&lt;sub&gt;2&lt;/sub&gt; gas mixture under non-uniform field on the basis of partial discharge properties

This paper investigates simultaneous measurements of partial discharge (PD) current and the corresponding light emission phenomena of C3F8/CO2 gas mixture under a non-uniform field with AC high voltage application in order to discuss the PD properties and breakdown mechanism of new gaseous dielectrics as SF6 substitutes. Perfluoro carbon (PFC) gas mixture is a possible candidate as SF6 substitute because it almost fulfills the environmental aspects, dielectric properties, boiling point, and other requirements of SF6 substitute. The authors simultaneously measured PD phenomena such as time-sequential PD current pulses and corresponding light emission images before breakdown during the positive half cycle of the applied AC voltage where most breakdowns occurred. Consequently, it was found that there were three kinds of current pulse patterns, which depended on the gas pressure and the applied voltage amplitude. It was also confirmed that breakdown occurred around the voltage peak, i.e. 90 degrees. of the applied voltage, irrespective of the PD pattern. Furthermore, the simultaneous measurements enabled the authors to classify the discharge area in the N-shaped characteristic of the breakdown voltage based on discrimination of discharge types between streamer and leader discharges. Namely, the location where leader discharge is generated by the transition from streamer discharge in the N-shaped characteristic was indicated. These experimental results and the simultaneous measurement technique will help clarify the breakdown mechanism for new gases or gas mixtures as SF6 substitutes. The obtained results will also contribute to insulation diagnosis for next-generation gas-insulated power apparatus with the newly developed gaseous dielectrics.

Measurement of Urethral Closure Function in Women With Stress Urinary Incontinence

We assessed the use of urethral pressure reflectometry in detecting pressure increases in the female urethra and compared the usefulness of urethral pressure reflectometry vs urethral pressure profilometry in a pharmacodynamic intervention study. In this randomized, double-blind, placebo controlled, crossover study 17 women with stress urinary incontinence or mixed urinary incontinence received 4 mg esreboxetine or placebo for 7 to 9 days followed by a washout period before crossing over treatments. Urethral pressure reflectometry and urethral pressure profilometry were performed before and at the end of each treatment period. The urethral opening pressure measured with urethral pressure reflectometry increased significantly compared to placebo by 13.7 cm H(2)O (p <0.0001) with an observed within subject standard deviation of 5.4. The increase in maximum urethral closure pressure was 8.4 cm H(2)O compared to placebo (p = 0.06) and for maximum urethral pressure the increase was 9.9 cm H(2)O (p = 0.04). However, the within subject SD for these parameters was higher at 11.4 and 12.2, respectively, implying lower power for these analyses. While receiving esreboxetine patients had significantly fewer incontinence episodes and reported a treatment benefit (global impression of change) compared to placebo. The opening pressure measured with urethral pressure reflectometry was less variable compared to the parameters measured with urethral pressure profilometry (maximum urethral closure pressure and maximum urethral pressure). Consequently using urethral pressure reflectometry would result in a more efficient study design when investigating pharmacological effects on the urethra in future studies. We also found that esreboxetine was well tolerated, and had a positive and clinically relevant effect on urethral closure function and symptoms of stress urinary incontinence.

Spectroscopy of neutron irradiation induced deep levels in silicon by microwave probed photoconductivity transients

A contactless technique for simultaneous measurements of the carrier lifetime and the parameters of deep levels has been applied. This method is based on microwave probed pulsed photoconductivity (MW-PC) spectroscopy in the wavelength range between 0.5 and 4 μm. Several deep levels in the range of 0.2–0.6 eV have been resolved from spectral analysis of microwave probed photoconductivity amplitude variations in the samples of Si grown by magnetic field applied Czochralski (MCz) technology. An amplitude of the revealed MW-PC spectral steps showed an increase with neutron irradiation fluence indicating an enhancement of density of the specific defects. Simultaneous variations of recombination lifetime with fluence of the reactor neutrons from 10 12 to 3×10 16 n/cm 2 in the MCz Si samples have been examined. Recombination features of the irradiated and annealed MCz Si structures are discussed by comparing carrier recombination parameters and deep-level MW-PC spectral data with characteristics measured by deep-level-transient spectroscopy (DLTS) in the range of moderate irradiation fluences.

Noncontact measurement of thermal and optical parameters of biological tissues and materials using IR laser radiometry

A technique for simultaneous measurements of the thermal diffusivity, specific heat, and effective absorbtion coefficient was developed. The technique is based on local heating of a sample by laser radiation and thermal imager measurement of the temperature field dynamics in the surface layer in both the heating and cooling stages. The technique includes a program for calculating the laser-induced temperature field in the sample volume and the determination of three parameters by the Levenberg-Marquardt algorithm to provide the best fit of calculations to experimental results. The statistical error of thermal diffusivity, specific heat, and effective absorbtion coefficient measurements was 5–6%. The technique efficiency was demonstrated by the example of the development of a thermal and optical equivalent of cartilage tissue, based on polyacrylamide hydrogel.

A222 燐光寿命を利用した流れの温度速度計測(燃焼科学と技術の新展開VI)

A simultaneous measurement technique of velocity and temperature distribution in a fluid flow was developed. Particle image velocimetry (PIV) was combined with a lifetime based scalar measurement technique. A measurement method based on the luminescent lifetime is appropriate for detecting the transient temperature field. Developed method needs a high speed camera, a laser (one excitation wave length) and temperature sensitive particles (TSParticles). The luminescence from TSParticles doped with EuTTA was detected by the high speed camera, which was not equipped with any image intensifier, at 15000 frames per second. Imaging at the high frame rate has a possibility to carry out PIV with a wide dynamic range. A decay of luminescent intensity was detected in detail. The decay curves at various temperature conditions were fitted well to exponential functions, from which the decay constant at each temperature was obtained. The proposed technique was applied to measure the temperature and the velocity field in a natural convection driven by Marangoni force and by buoyancy in a rectangular tank. The accuracy of the temperature measurement of the proposed technique was ±0.℃.

高速度カメラと燐光感温粒子を用いた寿命法による温度速度計測(流体工学,流体機械)

A simultaneous measurement technique of velocity and temperature distribution in a fluid flow was developed. Particle image velocimetry (PIV) was combined with a lifetime based scalar measurement technique. A measurement method based on the luminescent lifetime is appropriate for detecting the transient temperature field. Developed method needs a high speed camera, a laser (one excitation wave length) and temperature sensitive particles (TSParticles). The luminescence from TSParticles doped with EuTTA was detected by the high speed camera, which was not equipped with any image intensifier, at 15000 frames per second. Imaging at the high frame rate has a possibility to carry out PIV with a wide dynamic range. A decay of luminescent intensity was detected in detail. The decay curves at various temperature conditions were fitted well to exponential functions, from which the decay constant at each temperature was obtained. The proposed technique was applied to measure the temperature and the velocity field in a natural convection driven by Marangoni force and by buoyancy in a rectangular tank. The accuracy of the temperature measurement of the proposed technique was ±0.4℃.

The use of the photorefractive effect for comprehensive three-dimensional local measurements of electrical and thermal parameters of silicon structures

The photorefractive effect was studied as a basis for developing a new method of contactless comprehensive mapping of electrical and thermal properties of silicon structures. The possibility of making three-dimensional local measurements of the charge carrier mobility and lifetime and the thermal diffusivity in a single technological cycle at any point of the sample volume was shown. A new technique for the simultaneous measurement of all these parameters was developed.