Artykuły w czasopismach: „High Speed Probes”

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Richter, C., P. Weinzierl, W. Engl, C. Penzkofer, B. Irmer i T. Sulzbach. "Cantilever probes for high speed AFM". Microsystem Technologies 18, nr 7-8 (29.02.2012): 1119–26. http://dx.doi.org/10.1007/s00542-012-1454-8.

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Fahrbach, Michael, Sebastian Friedrich, Brunero Cappella i Erwin Peiner. "Calibrating a high-speed contact-resonance profilometer". Journal of Sensors and Sensor Systems 9, nr 2 (7.07.2020): 179–87. http://dx.doi.org/10.5194/jsss-9-179-2020.

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Abstract. A European EMPIR project, which aims to use large-scale, 5 mm × 200 µm × 50 µm (L×W×H), piezoresistive microprobes for contact resonance applications, a well-established measurement mode of atomic force microscopes (AFMs), is being funded. As the probes used in this project are much larger in size than typical AFM probes, however, some of the simplifications and assumptions made for AFM probes are not applicable. This study presents a guide on how to systematically create a model that replicates the dynamic behavior of microprobes. The model includes variables such as air damping, nonlinear sensitivities, and frequency dependencies. The finished model is then verified by analyzing a series of measurements.

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Schmirler, Michal. "Flight Speed Evaluation Using a Special Multi-Element High-Speed Temperature Probe". Aerospace 9, nr 4 (31.03.2022): 185. http://dx.doi.org/10.3390/aerospace9040185.

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In the context of aircraft aerodynamics, the compressibility of air flowing around the aircraft must always be considered. This fact brings with it one inconvenience: to evaluate the velocity of the flowing air (airspeed), it is necessary to know its temperature as well. Unfortunately, direct measurement of the temperature of air flowing at high speed (usually at Ma > 0.3) is practically impossible without knowledge of its velocity. Thus, there are two unknown quantities in the problem that depend on each other. The solution is achieved by a method that uses temperature probes composed of multiple sensors with different properties (different recovery factors). The comparison of rendered temperatures subsequently allows the elimination of the necessary knowledge of static temperature and the evaluation of velocity. In this paper, one of such probes is described together with its thermodynamic properties and possible applications.

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Croft, D., D. McAllister i S. Devasia. "High-Speed Scanning of Piezo-Probes for Nano-fabrication". Journal of Manufacturing Science and Engineering 120, nr 3 (1.08.1998): 617–22. http://dx.doi.org/10.1115/1.2830166.

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Low scanning speed of piezo-probes has been a fundamental limitation of scanning probe based nano-fabrication techniques. Typical scan-rates achieved are limited, by structural vibrations of the piezo-probe, to about 1/10th the fundamental vibrational frequency of the piezo-probe. Faster scanning of piezo-probes is achieved here (experimental results are presented) by using inversion of the piezo-dynamics—this approach uses a feedforward input voltage, applied to piezo-probe, to compensate for piezo vibrations.

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Kang, Yi Hua, Jun Tu, Jian Bo Wu i Yan Hua Sun. "The High-Speed Ultrasonic Testing Method for Steel Pipes Based on Linear Reciprocating Probes". Advanced Materials Research 301-303 (lipiec 2011): 919–23. http://dx.doi.org/10.4028/www.scientific.net/amr.301-303.919.

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This paper presents the high-speed ultrasonic testing methods for steel pipes currently, and points the existing difficulties, such as the instability in signal transmission, the problem of water coupling, and so on. Then the inspection method based on linear reciprocating probes is proposed to achieve the purpose of fewer probes and higher detecting speed. The mathematics model which adopts the slider-crank mechanism to realize the probes swinging fast in line is established as there is blind spot between the adjacent probes in high-speed inspection. With the help of simulation of Matlab, the relation curve between the rotation speed of crank and the rotation angle of crank is acquired, as well as the line speed of the steel pipe and the rotation angle of crank. The experiment platform is set up according to the simulation data, and the results verify the feasibility of the method.

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Imperatori, Giona, Paolo Cunzolo, Dragan Cvetkov i Diego Barrettino. "Wireless Surface Electromyography Probes With Four High-Speed Channels". IEEE Sensors Journal 13, nr 8 (sierpień 2013): 2954–61. http://dx.doi.org/10.1109/jsen.2013.2260145.

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Conn, D., H. X. Wu i M. Zhang. "Full wave electromagnetic simulation of electrooptic high-speed probes". Optical and Quantum Electronics 28, nr 7 (lipiec 1996): 765–82. http://dx.doi.org/10.1007/bf00820148.

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Rabjohn, G., J. Wolczanski i R. Surridge. "High-frequency wafer-probing techniques". Canadian Journal of Physics 65, nr 8 (1.08.1987): 850–55. http://dx.doi.org/10.1139/p87-130.

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High-speed digital and microwave circuits have traditionally been tested by dicing wafers and mounting chips into high-frequency test carriers. This process is expensive, time consuming, and destructive. Methods of high-frequency measurement at the wafer stage are very desirable; for example, for wafer mapping, but conventional needle probes cannot be used because of their parasitics. New probe structures based on fine coaxial lines, vertically mounted microstrip lines, and tapered coplanar lines have been reported.For measurement at microwave frequencies (2–20 GHz), we have developed a geometry of a coplanar wave-guide probe that gives better than 10 dB return loss. Individual monolithic components can easily be measured and modelled for inclusion in a circuit simulation.For the measurement of digital circuits, especially those requiring several high-speed signal lines, we have used proprietary microstrip probes. Satisfactory operation up to about 2 Gbit∙s−1 has been observed, the upper bit rate being restricted by the inductance of the probe tip.Microwave-frequency and time-domain measurements of both types of probes have been made and will be discussed. Additionally, examples of the use of these probes for on-wafer measurements of digital and analog circuits will be given.

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Mistry, Aashutosh. "Electrochemical high-speed AFM dynamically probes fast-charging battery materials". MRS Bulletin 45, nr 12 (grudzień 2020): 984–85. http://dx.doi.org/10.1557/mrs.2020.309.

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Korolev, Alexei, Edward Emery i Kirk Creelman. "Modification and Tests of Particle Probe Tips to Mitigate Effects of Ice Shattering". Journal of Atmospheric and Oceanic Technology 30, nr 4 (1.04.2013): 690–708. http://dx.doi.org/10.1175/jtech-d-12-00142.1.

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Abstract Ice particle shattering may significantly contaminate measurements taken by airborne particle probes in ice clouds. Environment Canada and the NASA Glenn Research Center (GRC) undertook efforts to modify and test probe tips in order to mitigate the effect of shattering on measurements. This work presents an overview of the results obtained during the design work on the particle probe arm tips. Even though this work was focused on the modifications of three of the probes—Particle Measuring Systems Inc. (PMS) Forward Scattering Spectrometer Probe and optical array probe, and Droplet Measurement Technologies (DMT) Cloud Imaging Probe—the outcomes of this work bear a general character and are applicable to other similar instruments. The results of the airflow analysis around the probe’s housing and the simulations of particle bouncing from the probe tips are discussed here. The originally designed and modified tips were tested in a high-speed wind tunnel in ice and liquid sprays. The ice particle bouncing processes as well as patterns of water shedding over the surface of the probes arms were studied with the help of a high-speed video camera. It was found that at aircraft speed, after bouncing from a solid surface, ice particles may travel several centimeters across the airflow and bounce forward up to 1 cm. For the first time it has been directly documented with high-speed video recording that the sample volumes of particle probes with the originally designed tips are contaminated by shattered and bounced particles. A set of recommendations on the existing modification and the design of future particle probe housings is presented.

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Shang, Zhen Tao, i Ying Jia. "Experimental Evaluations of High/Ultra-High Speed Grinding of Tungsten Carbide". Applied Mechanics and Materials 575 (czerwiec 2014): 350–54. http://dx.doi.org/10.4028/www.scientific.net/amm.575.350.

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According to broken edges and cracks emerging in traditionally machining cemented carbides (CP1) materials, this paper carried out some experimental researches on high and ultra-high grinding process for these materials, and considered the effect of process parameters on grinding forces, surface roughness, surface quality; discusses the calculation of the single grinding average normals force and relationship with maximum undeformed chip thickness and theoretical critical normal loads; probes the removal mechanisms of cemented carbide in high/ultra-high grinding process.

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Lee, Woo-Kyung, Minchul Yang, Arnaldo R. Laracuente, William P. King, Lloyd J. Whitman i Paul E. Sheehan. "Direct-write polymer nanolithography in ultra-high vacuum". Beilstein Journal of Nanotechnology 3 (19.01.2012): 52–56. http://dx.doi.org/10.3762/bjnano.3.6.

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Polymer nanostructures were directly written onto substrates in ultra-high vacuum. The polymer ink was coated onto atomic force microscope (AFM) probes that could be heated to control the ink viscosity. Then, the ink-coated probes were placed into an ultra-high vacuum (UHV) AFM and used to write polymer nanostructures on surfaces, including surfaces cleaned in UHV. Controlling the writing speed of the tip enabled the control over the number of monolayers of the polymer ink deposited on the surface from a single to tens of monolayers, with higher writing speeds generating thinner polymer nanostructures. Deposition onto silicon oxide-terminated substrates led to polymer chains standing upright on the surface, whereas deposition onto vacuum reconstructed silicon yielded polymer chains aligned along the surface.

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13

Lawson, R. Paul, Darren O’Connor, Patrick Zmarzly, Kim Weaver, Brad Baker, Qixu Mo i Haflidi Jonsson. "The 2D-S (Stereo) Probe: Design and Preliminary Tests of a New Airborne, High-Speed, High-Resolution Particle Imaging Probe". Journal of Atmospheric and Oceanic Technology 23, nr 11 (1.11.2006): 1462–77. http://dx.doi.org/10.1175/jtech1927.1.

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Abstract The design, laboratory calibrations, and flight tests of a new optical imaging instrument, the two-dimensional stereo (2D-S) probe, are presented. Two orthogonal laser beams cross in the middle of the sample volume. Custom, high-speed, 128-photodiode linear arrays and electronics produce shadowgraph images with true 10-μm pixel resolution at aircraft speeds up to 250 m s−1. An overlap region is defined by the two laser beams, improving the sample volume boundaries and sizing of small (<∼100 μm) particles, compared to conventional optical array probes. The stereo views of particles in the overlap region can also improve determination of three-dimensional properties of some particles. Data collected by three research aircraft are examined and discussed. The 2D-S sees fine details of ice crystals and small water drops coexisting in mixed-phase cloud. Measurements in warm cumuli collected by the NCAR C-130 during the Rain in Cumulus over the Ocean (RICO) project provide a test bed to compare the 2D-S with 2D cloud (2D-C) and 260X probes. The 2D-S sees thousands of cloud drops <∼150 μm when the 2D-C and 260X probes see few or none. The data suggest that particle images and size distributions ranging from 25 to ∼150 μm and collected at airspeeds >100 m s−1 by the 2D-C and 260X probes are probably (erroneously) generated from out-of-focus particles. Development of the 2D-S is in its infancy, and much work needs to be done to quantify its performance and generate software to analyze data.

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Dugel, Pravin U., Dina J. K. Abulon i Ramon Dimalanta. "COMPARISON OF ATTRACTION CAPABILITIES ASSOCIATED WITH HIGH-SPEED, DUAL-PNEUMATIC VITRECTOMY PROBES". Retina 35, nr 5 (maj 2015): 915–20. http://dx.doi.org/10.1097/iae.0000000000000411.

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Coldrick, Simon, Paul Ivey i Roger Wells. "Considerations for Using 3-D Pneumatic Probes in High-Speed Axial Compressors". Journal of Turbomachinery 125, nr 1 (1.01.2003): 149–54. http://dx.doi.org/10.1115/1.1515334.

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This paper describes preparatory work towards three-dimensional flowfield measurements downstream of the rotor in an industrial, multistage, axial compressor, using a pneumatic pressure probe. The probe is of the steady-state four-hole cobra probe type. The design manufacture and calibration of the probe is described. CFD calculations have been undertaken in order to assess the feasibility of using such a probe in the high-speed compressor environment where space is limited. This includes effects of mounting the probe in close proximity to the downstream stator blades and whether it is necessary to adjust the calibration data to compensate for these effects.

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Alich, Therese C., Milan Pabst, Leonie Pothmann, Bálint Szalontai, Guido C. Faas i Istvan Mody. "A dark quencher genetically encodable voltage indicator (dqGEVI) exhibits high fidelity and speed". Proceedings of the National Academy of Sciences 118, nr 6 (2.02.2021): e2020235118. http://dx.doi.org/10.1073/pnas.2020235118.

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Voltage sensing with genetically expressed optical probes is highly desirable for large-scale recordings of neuronal activity and detection of localized voltage signals in single neurons. Most genetically encodable voltage indicators (GEVI) have drawbacks including slow response, low fluorescence, or excessive bleaching. Here we present a dark quencher GEVI approach (dqGEVI) using a Förster resonance energy transfer pair between a fluorophore glycosylphosphatidylinositol–enhanced green fluorescent protein (GPI-eGFP) on the outer surface of the neuronal membrane and an azo-benzene dye quencher (D3) that rapidly moves in the membrane driven by voltage. In contrast to previous probes, the sensor has a single photon bleaching time constant of ∼40 min, has a high temporal resolution and fidelity for detecting action potential firing at 100 Hz, resolves membrane de- and hyperpolarizations of a few millivolts, and has negligible effects on passive membrane properties or synaptic events. The dqGEVI approach should be a valuable tool for optical recordings of subcellular or population membrane potential changes in nerve cells.

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Gilchrist, B. E., S. G. Bilen, E. Choiniere, A. D. Gallimore i T. B. Smith. "Analysis of chamber simulations of long collecting probes in high-speed dense plasmas". IEEE Transactions on Plasma Science 30, nr 5 (październik 2002): 2023–34. http://dx.doi.org/10.1109/tps.2002.807538.

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Weigel, Ralf, Peter Spichtinger, Christoph Mahnke, Marcus Klingebiel, Armin Afchine, Andreas Petzold, Martina Krämer i in. "Thermodynamic correction of particle concentrations measured by underwing probes on fast-flying aircraft". Atmospheric Measurement Techniques 9, nr 10 (20.10.2016): 5135–62. http://dx.doi.org/10.5194/amt-9-5135-2016.

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Abstract. Particle concentration measurements with underwing probes on aircraft are impacted by air compression upstream of the instrument body as a function of flight velocity. In particular, for fast-flying aircraft the necessity arises to account for compression of the air sample volume. Hence, a correction procedure is needed to invert measured particle number concentrations to ambient conditions that is commonly applicable to different instruments to gain comparable results. In the compression region where the detection of particles occurs (i.e. under factual measurement conditions), pressure and temperature of the air sample are increased compared to ambient (undisturbed) conditions in certain distance away from the aircraft. Conventional procedures for scaling the measured number densities to ambient conditions presume that the air volume probed per time interval is determined by the aircraft speed (true air speed, TAS). However, particle imaging instruments equipped with pitot tubes measuring the probe air speed (PAS) of each underwing probe reveal PAS values systematically below those of the TAS. We conclude that the deviation between PAS and TAS is mainly caused by the compression of the probed air sample. From measurements during two missions in 2014 with the German Gulfstream G-550 (HALO – High Altitude LOng range) research aircraft we develop a procedure to correct the measured particle concentration to ambient conditions using a thermodynamic approach. With the provided equation, the corresponding concentration correction factor ξ is applicable to the high-frequency measurements of the underwing probes, each of which is equipped with its own air speed sensor (e.g. a pitot tube). ξ values of 1 to 0.85 are calculated for air speeds (i.e. TAS) between 60 and 250 m s−1. For different instruments at individual wing position the calculated ξ values exhibit strong consistency, which allows for a parameterisation of ξ as a function of TAS for the current HALO underwing probe configuration. The ability of cloud particles to adopt changes of air speed between ambient and measurement conditions depends on the cloud particles' inertia as a function of particle size (diameter Dp). The suggested inertia correction factor μ (Dp) for liquid cloud drops ranges between 1 (for Dp < 70 µm) and 0.8 (for 100 µm < Dp < 225 µm) but it needs to be applied carefully with respect to the particles' phase and nature. The correction of measured concentration by both factors, ξ and μ (Dp), yields higher ambient particle concentration by about 10–25 % compared to conventional procedures – an improvement which can be considered as significant for many research applications. The calculated ξ values are specifically related to the considered HALO underwing probe arrangement and may differ for other aircraft. Moreover, suggested corrections may not cover all impacts originating from high flight velocities and from interferences between the instruments and e.g. the aircraft wings and/or fuselage. Consequently, it is important that PAS (as a function of TAS) is individually measured by each probe deployed underneath the wings of a fast-flying aircraft.

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Jin, Hyeon. "An Experimental Study on Internal Drag Correction of High Speed Vehicle Using Three Probes". Journal of the Korean Society for Aeronautical & Space Sciences 49, nr 7 (31.07.2021): 529–37. http://dx.doi.org/10.5139/jksas.2021.49.7.529.

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Bell, Iverson C., Omar Leon, Grant C. Miars i Brian E. Gilchrist. "Experimental Investigation of Electron Collection by Rectangular Cuboid Probes in a High-Speed Plasma". IEEE Transactions on Plasma Science 45, nr 7 (lipiec 2017): 1788–802. http://dx.doi.org/10.1109/tps.2017.2706307.

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Schilden, Thomas, i Wolfgang Schröder. "Numerical analysis of high speed wind tunnel flow disturbance measurements using stagnation point probes". Journal of Fluid Mechanics 833 (3.11.2017): 247–73. http://dx.doi.org/10.1017/jfm.2017.674.

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Since supersonic test facilities have tunnel noise that strongly influences boundary layer transition experiments, the determination of tunnel noise is of great significance to properly evaluate and interpret experimental results. The composition of tunnel noise, which consists of acoustic, entropy and vorticity modes, highly influences the boundary layer receptivity. The measurement of the separate modes is a major goal of ongoing research. In this study, the properties of stagnation point probes for a newly developed modal decomposition method for tunnel noise are investigated by direct numerical simulation. Pressure and heat flux responses of a stagnation point probe to various entropy and acoustic mode input functions are analysed to investigate how tunnel noise is perceived by corresponding sensor types. The interaction of the incident mode and the shock wave upstream of the probe is analysed and the resulting wave pattern in the subsonic region between shock wave and probe is evidenced. It is found that pure incident acoustic or entropy modes cause acoustic and entropy waves downstream of the shock wave whose strengths differ depending on the incident mode. The resulting wave pattern downstream of the shock wave is determined by postshock acoustic waves propagating bidirectionally between shock wave and probe. Formulating a model equation linking pressure and heat flux fluctuations to the initially caused postshock acoustic and entropy wave, a criterion for the applicability of stagnation point probes measuring pressure and heat flux fluctuations in the new modal decomposition method can be deduced: to distinguish between the incident mode types based on their pressure and heat flux signal the perception of initially generated entropy waves downstream of the shock wave by the heat flux sensor is crucial. The transfer function between entropy waves and heat flux is shown to have low pass filter characteristics and the cutoff Strouhal number could be estimated by control theory. The analysis of the frequency response to continuous incident waves corroborated this cutoff Strouhal number.

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Wang, Jin, Zhi Ling Sun, Qi Chang Guo i Min Quan Huang. "Design of a Parallel Ultrasonic Inspection System for Wheels of High Speed Trains". Advanced Materials Research 562-564 (sierpień 2012): 2007–10. http://dx.doi.org/10.4028/www.scientific.net/amr.562-564.2007.

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This thesis proposes a new inspection system for wheels of high speed trains, using Piezoelectric ultrasonic technology and parallel processing technology. This system allows all the wheelsets mounted in a train to be inspected within a few minutes. When a train passes through the testing line at low speed(3-5Km/h), wheel tread contact with the probe arrays in turn, which are installed inside of a special rails. Meanwhile, ultrasonic controllers stimulate the probes , collect inspection data and transfer the data to the host computer. Application results in field are presented to verify the effectiveness of the proposed structure.

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Morgner, Frank, Alexandre Lecointre, Loïc J. Charbonnière i Hans-Gerd Löhmannsröben. "Detecting free hemoglobin in blood plasma and serum with luminescent terbium complexes". Physical Chemistry Chemical Physics 17, nr 3 (2015): 1740–45. http://dx.doi.org/10.1039/c4cp04206a.

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An optical analysis of the interaction of luminescent terbium complexes with hemoglobin is presented. Terbium probes allow for hemoglobin detection in biosamples with high speed and accuracy at low costs.

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Nagel, Dagmar, Uwe Maixner, Walter Strapp i Mohammed Wasey. "Advancements in Techniques for Calibration and Characterization of In Situ Optical Particle Measuring Probes, and Applications to the FSSP-100 Probe". Journal of Atmospheric and Oceanic Technology 24, nr 5 (1.05.2007): 745–60. http://dx.doi.org/10.1175/jtech2006.1.

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Abstract Advancements in techniques for the operational calibration and characterization of instrument performance of the Particle Measuring Systems, Inc. (PMS), forward scattering spectrometer probe (FSSP) and optical array probes (OAPs) are presented, which also can be used for most in situ particle-measuring optical probes on the market. These techniques include the determination of a distortion matrix to correct for instrumental broadening of the measured particle size distribution. A new version of a monodisperse droplet generator is introduced for absolute calibration in the size range between 10 and 100 μm. In addition, a high-speed technique was employed for the determination of airspeed influence on the sample volume and the sizing of particles. The calibration of a PMS FSSP with real water droplets may be significantly different from the usual calibration with glass beads. High-speed measurements simulate particles at speeds of up to about 250 m s−1. Particle undersizing and the decrease of the sample volume with increasing airspeed are described. The use of the modular tools, built for this work, is discussed for probe alignment, functionality checks, and general characterization and diagnostics both in laboratory and field environments.

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Weigel, R., P. Spichtinger, C. Mahnke, M. Klingebiel, A. Afchine, A. Petzold, M. Krämer i in. "Thermodynamic correction of particle concentrations measured by underwing probes on fast flying aircraft". Atmospheric Measurement Techniques Discussions 8, nr 12 (18.12.2015): 13423–69. http://dx.doi.org/10.5194/amtd-8-13423-2015.

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Abstract. Particle concentration measurements with underwing probes on aircraft are impacted by air compression upstream of the instrument body as a function of flight velocity. In particular for fast-flying aircraft the necessity arises to account for compression of the air sample volume. Hence, a correction procedure is needed to invert measured particle number concentrations to ambient conditions that is commonly applicable for different instruments to gain comparable results. In the compression region where the detection of particles occurs (i.e. under factual measurement conditions), pressure and temperature of the air sample are increased compared to ambient (undisturbed) conditions in certain distance away from the aircraft. Conventional procedures for scaling the measured number densities to ambient conditions presume that the particle penetration speed through the instruments' detection area equals the aircraft speed (True Air Speed, TAS). However, particle imaging instruments equipped with pitot-tubes measuring the Probe Air Speed (PAS) of each underwing probe reveal PAS values systematically below those of the TAS. We conclude that the deviation between PAS and TAS is mainly caused by the compression of the probed air sample. From measurements during two missions in 2014 with the German Gulfstream G-550 (HALO – High Altitude LOng range) research aircraft we develop a procedure to correct the measured particle concentration to ambient conditions using a thermodynamic approach. With the provided equation the corresponding concentration correction factor ξ is applicable to the high frequency measurements of each underwing probe which is equipped with its own air speed sensor (e.g. a pitot-tube). ξ-values of 1 to 0.85 are calculated for air speeds (i.e. TAS) between 60 and 260 m s−1. From HALO data it is found that ξ does not significantly vary between the different deployed instruments. Thus, for the current HALO underwing probe configuration a parameterisation of ξ as a function of TAS is provided for instances if PAS measurements are lacking. The ξ-correction yields higher ambient particle concentration by about 15–25 % compared to conventional procedures – an improvement which can be considered as significant for many research applications. The calculated ξ-values are specifically related to the considered HALO underwing probe arrangement and may differ for other aircraft or instrument geometries. Moreover, the ξ-correction may not cover all impacts originating from high flight velocities and from interferences between the instruments and, e.g., the aircraft wings and/or fuselage. Consequently, it is important that PAS (as a function of TAS) is individually measured by each probe deployed underneath the wings of a fast-flying aircraft.

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Popp, Johannes, Barbara Messner i Werner Steimer. "High-speed genotyping of CYP1A2*1F mutation with fluorescent hybridization probes using the LightCycler™". Pharmacogenomics 4, nr 5 (wrzesień 2003): 643–46. http://dx.doi.org/10.1517/phgs.4.5.643.23798.

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Nakanishi, Takuji, Yasuhiro Yokoyama i Atsushi Yarai. "Optimum design of arrayed multi-probes on high-speed photopyroelectric thermal wave tomographic imaging equipment". Electronics and Communications in Japan (Part II: Electronics) 80, nr 7 (lipiec 1997): 47–55. http://dx.doi.org/10.1002/(sici)1520-6432(199707)80:7<47::aid-ecjb6>3.0.co;2-0.

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Heinricht, F. "High-Speed Reflection Electron Microscopy of Laser-Induced Surface Transitions". Proceedings, annual meeting, Electron Microscopy Society of America 48, nr 1 (12.08.1990): 312–13. http://dx.doi.org/10.1017/s0424820100180318.

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Micropatterning of bulk material by pulsed laser radiation is a promising technique for many applications, e.g. drilling and data storage. Due to the fact that laser radiation can be applied very localized, high power densities in a small volume of the treated specimen can be realized. As a result of rapid heat-up and cool-down processes, unusual phases and microstructures can be generated.Time-resolving methods, especially imaging with short exposures times are quite useful in order to understand the physics standing behind. As a diagnostic tool electrons are superior to other probes, e.g. light optics, due to their sensitivity to topography, material composition and structure. Unfortunately , the SEM - one of the most common microscopes for surface analysis - cannot be used for investigations in the the nanoseconds time domain due to its far to slow scan time. On the other hand, the reflection electron microscope (REM) is one of the very few instruments, which is capable to image all points of the treated surface simultanously.In order to achieve electron optical images of laser pulse induced processes on surfaces with exposures times of a few nanoseconds, a high-speed REM was developed. This new instrument is based on a conventional TEM, additionally equipped with the following units:- a laser pulsed thermal electron gun, which delivers high-brightness electron pulses with duration of 20ns.

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Sahoo, Gourishankar, Rita Paikaray, Subrata Samantaray, Dheeren Chandra Patra, Narayan Chandra Sasini, Joydeep Ghosh, Malay Bikash Chowdhuri i Amulya Sanyasi. "A Compact Plasma System for Experimental Study". Applied Mechanics and Materials 278-280 (styczeń 2013): 90–100. http://dx.doi.org/10.4028/www.scientific.net/amm.278-280.90.

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A compact plasma system is set up at Ravenshaw University, India. The plasma system consists of a curved vacuum chamber which is nothing but a part of a toroid (θ=700) having minor radius, r= 0.3 m and major radius, R= 0.5 m, vacuum system, electromagnet, gas injected washer stacked plasma gun to produce plasma blobs/filaments, pulse forming network to energise plasma gun, diagnostic tools like electric probes, magnetic probes, spectrometer, high speed CCD camera, digital pulse/delay generator to synchronise the diagnostic tools. A pair of copper coil is wound over the chamber and capacitive pulse is fed to the coil to produce non-uniform magnetic field inside the chamber. The gas injected washer stacked plasma gun is a mono-anode - multi cathode system having five cathodes made up of brass and an anode made up of copper. The gun impedance is ~ 15 Ω. The pulse forming network (PFN) is Guillemin E type which consists of capacitors having equal capacitance 5.5 μF and inductors having equal inductances 1.5 μH. The pulse width of the PFN is ~ 7.6 μs for a seven stage network, as tested with known resistive circuit. Magnetic probes are designed and calibrated using a Helmholtz coil to map the radial magnetic field profile of the plasma chamber. Electric probes like Langmuir triple probe, velocity probes are designed to measure plasma parameters like blob velocity, density, temperature etc. Emission spectroscopy method is used to identify charged species inside the plasma. High speed CCD camera is used to interpret the structure of the plasma. A digital pulse/trigger generator is used to synchronise the CCD, spectrometer and switching thyristor etc. Preliminary results are also reported.

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Soper, David, Dominic Flynn, Chris Baker, Adam Jackson i Hassan Hemida. "A comparative study of methods to simulate aerodynamic flow beneath a high-speed train". Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit 232, nr 5 (5.10.2017): 1464–82. http://dx.doi.org/10.1177/0954409717734090.

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The introduction of dedicated high-speed railway lines around the world has led to issues associated with running trains at very high speeds. Aerodynamic effects proportionally increase with train speed squared; consequently, at higher speeds aerodynamic effects will be significantly greater than those of trains travelling at lower speeds. On ballasted track beds, the phenomenon in which ballast particles become airborne during the passage of a high-speed train has led to the need for understanding the processes involved in train and track interaction (both aerodynamical and geotechnical). The difficulty in making full-scale aerodynamic measurements beneath a high-speed train has created the requirement to be able to accurately simulate these complex aerodynamic flows at the model scale. In this study, the results of moving-model tests and numerical simulations were analysed to determine the performance of each method for simulating the aerodynamic flow underneath a high-speed train. Validation was provided for both cases by juxtaposing the results against those from full-scale measurements. The moving-model tests and numerical simulations were performed at the 1/25th scale. Horizontal velocities from the moving-model tests and computational fluid dynamics simulations were mostly comparable except those obtained close to the ballast. In this region, multi-hole aerodynamic probes were unable to accurately measure velocities. The numerical simulations were able to resolve the flow to much smaller turbulent scales than could be measured in the experiments and showed an overshoot in peak velocity magnitudes. Pressure and velocity magnitudes were found to be greater in the numerical simulations than in the experimental tests. This is thought to be due to the influence of ballast stones in the experimental studies allowing the flow to diffuse through them, whereas in the computational fluid dynamics simulations, the flow stagnated on a smooth non-porous surface. Additional validation of standard deviations and turbulence intensities found good agreement between the experimental data but an overshoot in the numerical simulations. Both moving model and computational fluid dynamics techniques were shown to be able to replicate the flow development beneath a high-speed train. These techniques could therefore be used as a method to model underbody flow with a view to train homologation.

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Opaliński, M., P. Mazuro, A. Klasik i E. Rostek. "Tribological Examination of Different Steel Materials after Special Heat Treatment and Salt Bath Nitriding". Archives of Metallurgy and Materials 61, nr 4 (1.12.2016): 1881–88. http://dx.doi.org/10.1515/amm-2016-0303.

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Abstract The main aim of the presented research was examination of new tribological pairs made of different types of steel. Materials of disc probes were submitted to unusual heat treatment processes and salt bath nitriding. The research is focused on the friction coefficients and mass losses of the material probes. Based on the results it was noticed that the best wear resistant pair was bearing steel 100Cr6 coupled with high speed steel S705. The lowest friction coefficient appeared for the pair bearing steel 100Cr6 and maraging steel C350.

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Zhang, Chen Kai, Jun Hu, Zhi Qiang Wang i Shi Qi Yu. "Experimental Studies of the Endwall Flow in a Multistage Low-Speed Axial Compressor". Advanced Materials Research 718-720 (lipiec 2013): 1504–9. http://dx.doi.org/10.4028/www.scientific.net/amr.718-720.1504.

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Detailed flowfield measurements are made in the end-wall region of a four-stage low-speed large-scare axial compressor test rig. Two ten-hole survey boundary layer probes, one four-hole pneumatic probe, and six dynamic pressure probes each bedded with a high-frequence response Kulite sensor, are designed and manufactured to aid the test. Boundary layer region and mainflow region can be clearly distinguished from the boundary layer measurement results. A few parameters, including boundary layer thickness, displace thickness, momentum loss thickness, energy loss thickness and blockage coefficient are calculated based on the measurements. Results from turbulent boundary layer empirical formula of plate are in good agreement with the mesurements, indicating a way of boundary layer effect estimation. The evolution trajectory of TCV is identified evidently by dynamic pressure measurements. The maximum aerodynamic load point on the blade moves from the trailing to the leading edge as flowrate decreases, which leads to the forward movement of the tip clearance vortex inception point.

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SENOO, Makoto, Tatsuyuki OMOTE, Kazunori KOGA i Kenji TSUCHITA. "High Speed Imaging and Automatic Recognition of Fuel ID Numbers Using Linear Array Type Ultrasonic Probes." Journal of the Atomic Energy Society of Japan / Atomic Energy Society of Japan 36, nr 8 (1994): 759–68. http://dx.doi.org/10.3327/jaesj.36.759.

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Fernández Oro, J. M., K. M. Argüelles Díaz, M. Rodríguez Lastra, M. Galdo Vega i B. Pereiras García. "Converged statistics for time-resolved measurements in low-speed axial fans using high-frequency response probes". Experimental Thermal and Fluid Science 54 (kwiecień 2014): 71–84. http://dx.doi.org/10.1016/j.expthermflusci.2014.02.002.

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Li, Yu, Xin Lin Long i Jun Yong Lu. "Measurement of the Armature Speed in Electromagnetic Launching Process Using B-Dot Probes". Applied Mechanics and Materials 701-702 (grudzień 2014): 514–17. http://dx.doi.org/10.4028/www.scientific.net/amm.701-702.514.

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In this paper, the sensing principle of a B-dot probe to measure the armature position was analyzed. The output waveforms of the probe for two different orientations were given after mathematical deduction. An electromagnetic launching experiment was conducted, and the result shows that the output waveforms of the probes can present the velocity trend of the armature. After data fitting, the velocity of the armature moving in the bore was given, and combined with the waveform of the muzzle voltage, the muzzle velocity was obtained, which matched the measurement result by a high speed camera well.

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Traverso, Alberto, Federico Reggio, Paolo Silvestri, Sergio Rizzo, Geoff Engelbrecht i Alexandros Chasoglou. "Two-phase flow expansion: development of an innovative test-rig for flow characterisation and CFD validation". E3S Web of Conferences 113 (2019): 03017. http://dx.doi.org/10.1051/e3sconf/201911303017.

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The aim of this work is to describe the design of an innovative test rig for investigating the expansion of saturated fluids in the two-phase region. The experimental test rig was thought up and built by TPG of the University of Genoa. It will be equipped by probes and some optical accesses that permit high speed video recording and laser measurements. It will be useful for the study of the quality ratio, vapour and liquid droplet thermodynamic properties and their speed.

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Brodersen, S., i D. Wulff. "Measurements of the Pressure and Velocity Distribution in Low-Speed Turbomachinery by Means of High-Frequency Pressure Transducers". Journal of Turbomachinery 114, nr 1 (1.01.1992): 100–107. http://dx.doi.org/10.1115/1.2927972.

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The flow in a low-speed, single-state compressor with a very high blade loading has been measured using a two-probe arrangement. The measuring technique and data reduction procedure described have been especially adjusted for application in low-speed turbomachinery. Those machines show only small pressure fluctuations in the flow downstream of the rotor, for which specific requirements concerning the measuring technique have been taken into account. The probes used contain unsteady pressure transducers and simulate an unsteady multisensor pressure probe. This technique proves to be suitable for applications in low-speed turbomachinery. The measurements are based on phase-locked ensemble averages of multiple samples, where the data are acquired using a simple and convenient experimental setup. This allows the velocity and pressure distribution of the flow to be determined in rotor coordinates. The results show the flow field and the loss distribution of an aero-dynamically highly loaded rotor at design flow rate.

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Choiniere, E., S. G. Bilen, B. E. Gilchrist, K. R. Fuhrhop i A. D. Gallimore. "Experimental investigation of electron collection to solid and slotted tape probes in a high-speed flowing plasma". IEEE Transactions on Plasma Science 33, nr 4 (sierpień 2005): 1310–23. http://dx.doi.org/10.1109/tps.2005.852366.

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McMillan, Justine M., Alex E. Hay, Rolf G. Lueck i Fabian Wolk. "Rates of Dissipation of Turbulent Kinetic Energy in a High Reynolds Number Tidal Channel". Journal of Atmospheric and Oceanic Technology 33, nr 4 (kwiecień 2016): 817–37. http://dx.doi.org/10.1175/jtech-d-15-0167.1.

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AbstractThe ability to estimate the rate of dissipation (ε) of turbulent kinetic energy at middepth in a high-speed tidal channel using broadband acoustic Doppler current profilers (ADCPs) is assessed by making comparisons to direct measurements of ε obtained using shear probes mounted on a streamlined underwater buoy. The investigation was carried out in Grand Passage, Nova Scotia, Canada, where the depth-averaged flow speed reached 2 m s−1 and the Reynolds number was 8 × 107. The speed bin–averaged dissipation rates estimated from the ADCP data agree with the shear probe data to within a factor of 2. Both the ADCP and the shear probe measurements indicate a linear dependence of ε on the cube of the flow speed during flood and much lower dissipation rates during ebb. The ebb–flood asymmetry and the small-scale intermittency in ε are also apparent in the lognormal distributions of the shear probe data. Possible sources of bias and error in the ε estimates are investigated, and the most likely causes of the discrepancy between the ADCP and shear probe estimates are the cross-channel separation of the instruments and the high degree of spatial variability that exists in the channel.

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Vaughan, Gavin B. M., Robert Baker, Raymond Barret, Julien Bonnefoy, Thomas Buslaps, Stefano Checchia, Denis Duran i in. "ID15A at the ESRF – a beamline for high speed operando X-ray diffraction, diffraction tomography and total scattering". Journal of Synchrotron Radiation 27, nr 2 (28.01.2020): 515–28. http://dx.doi.org/10.1107/s1600577519016813.

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ID15A is a newly refurbished beamline at the ESRF devoted to operando and time-resolved diffraction and imaging, total scattering and diffraction computed tomography. The beamline is optimized for rapid alternation between the different techniques during a single operando experiment in order to collect complementary data on working systems. The high available energy (up to 120 keV) means that even bulky and highly absorbing systems may be studied. The beamline is equipped with optimized focusing optics and a photon-counting CdTe pixel detector, allowing for both unprecedented data quality at high energy and for very rapid triggered experiments. A large choice of imaging detectors and ancillary probes and sample environments is also available.

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Hathaway, M. D., J. R. Wood i C. A. Wasserbauer. "NASA Low-Speed Centrifugal Compressor for Three-Dimensional Viscous Code Assessment and Fundamental Flow Physics Research". Journal of Turbomachinery 114, nr 2 (1.04.1992): 295–303. http://dx.doi.org/10.1115/1.2929143.

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A low-speed centrifugal compressor facility recently built by the NASA Lewis Research Center is described. The purpose of this facility is to obtain detailed flow field measurements for computational fluid dynamic code assessment and flow physics modeling in support of Army and NASA efforts to advance small gas turbine engine technology. The facility is heavily instrumented with pressure and temperature probes, in both the stationary and rotating frames of reference, and has provisions for flow visualization and laser velocimetry. The facility will accommodate rotational speeds to 2400 rpm and is rated at pressures to 1.25 atm. The initial compressor stage being tested is geometrically and dynamically representative of modern high-performance centrifugal compressor stages with the exception of Mach number levels. Preliminary experimental investigations of inlet and exit flow uniformity and measurement repeatability are presented. These results demonstrate the high quality of the data that may be expected from this facility. The significance of synergism between computational fluid dynamic analyses and experimentation throughout the development of the low-speed centrifugal compressor facility is demonstrated.

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do Vale Pereira, Paula, Michael J. Durka, Bartholomew P. Hogan, Kristof Richmond, Miles W. E. Smith, Dale P. Winebrenner, W. Timothy Elam i in. "Experimental Validation of Cryobot Thermal Models for the Exploration of Ocean Worlds". Planetary Science Journal 4, nr 5 (1.05.2023): 81. http://dx.doi.org/10.3847/psj/acc2b7.

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Abstract Accessing the potentially habitable subsurface waters of Ocean Worlds requires a robotic ice probe (or “cryobot”) to traverse tens of kilometers of ice with temperatures ranging from ∼100 to 273 K. Designing and planning such a mission requires understanding ice probe behavior as a function of the local environment and design parameters. We present experimental results of two laboratory melt probes in cryogenic (79 K) and warm (253 K) ice. The melt probe tested in warm ice had multiple adjustable heaters, enabling optimization of the system's efficiency. The melt probes tested in cryogenic ice operated in vacuum and had internal tether spools, allowing for experimental confirmation of hole closure and the creation of a pressurized pocket with liquid water around the probe. These melt probes were tested at power levels ranging from 120 to 1135 W, achieving descent speeds between 5.3 and 59 cm hr−1. By analyzing the relationship between power and speed using analytical and high-fidelity numerical models, we demonstrate progress in understanding melt probe performance. We distinguish between the previously confounding terms of probe operational inefficiency and analytical model inaccuracy, allowing us to understand the range of applicability of the analytical models and demonstrate the importance of controlling heat distribution in cryobot design. The validated models show that while numerical models may be required to describe the behavior of short probes descending in limited-size laboratory test beds, the performance of efficient cryobots designed for operation on Ocean Worlds can be predicted by analytical models within 5% error.

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De´nos, R., i C. H. Sieverding. "Assessment of the Cold-Wire Resistance Thermometer for High-Speed Turbomachinery Applications". Journal of Turbomachinery 119, nr 1 (1.01.1997): 140–48. http://dx.doi.org/10.1115/1.2841002.

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The paper first describes the fundamentals of cold-wire resistance thermometry. The transfer functions with and without wire-prong heat conduction effects are discussed and a new method for the description of complicated transfer functions describing both the prongs and wire frequency response is proposed. The experimental part of the paper starts with an investigation of the transfer function of various probes differing by the wire diameter, the l/d ratio, and the wire-prong connection using two simple methods: (1) electrical heating of the wire by a sine current and (2) a temperature step test consisting in injecting the probe into a hot air stream. The first test provides information on the wire response, whereas the second serves to study wire prong heat conduction effect. The tests cover a wide range of velocities and densities. A frequency bandwidth of 2 kHz is obtained with a 2.5 μm wire probe at an air velocity of 200 m/s at atmospheric pressure. A numerical compensation system allows us to extend the use of this probe to much higher frequencies. Finally, the probe is mounted onto a wheel in a high-speed rotating test rig allowing probe traverses through a stationary hot air jet at rotational speeds up to 5000 rpm with the probe positioned at a radius of 0.380 m. The probe signal is transmitted via an opto-electronic data transmission system. It is demonstrated that using the numerical compensation method, it is possible to reconstruct the hot jet temperature profile at frequencies up to 6 kHz.

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Lee, Bryan, Tristan Hegseth i Xiaoshan Zhu. "Optical Properties of Mn-Doped CuGa(In)S-ZnS Nanocrystals (NCs): Effects of Host NC and Mn Concentration". Nanomaterials 12, nr 6 (17.03.2022): 994. http://dx.doi.org/10.3390/nano12060994.

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Time-gated fluorescence measurement (TGFM) using long-life fluorescence probes is a highly sensitive fluorescence-measurement technology due to the inherently high signal-to-background ratio. Although many probes for TGFM such as luminescent-metal-complex probes and lanthanide-doped nanoparticles are in development, they generally need sophisticated/expensive instruments for biosensing/imaging applications. Probes possessing high brightness, low-energy (visible light) excitation, and long lifetimes up to milliseconds of luminescence, are highly desired in order to simplify the optical and electronic design of time-gated instruments (e.g., adopting non-UV-grade optics or low-speed electronics), lower the instrument complexity and cost, and facilitate broader applications of TGFM. In this work, we developed Mn-doped CuGa(In)S-ZnS nanocrystals (NCs) using simple and standard synthetic steps to achieve all the desired optical features in order to investigate how the optical properties (fluorescence/absorption spectra, brightness, and lifetimes) of the Mn-doped NCs are affected by different host NCs and Mn concentrations in host NCs. With optimal synthetic conditions, a library of Mn-doped NCs was achieved that possessed high brightness (up to 47% quantum yield), low-energy excitation (by 405 nm visible light), and long lifetimes (up to 3.67 ms). Additionally, the time-domain fluorescence characteristics of optimal Mn-doped NCs were measured under pulsed 405 nm laser excitation and bandpass-filter-based emission collection. The measurement results indicate the feasibility of these optimal Mn-doped NCs in TGFM-based biosensing/imaging.

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Liebold, F., H. G. Maas i A. A. Heravi. "CRACK WIDTH MEASUREMENT FOR NON-PLANAR SURFACES BY TRIANGLE MESH ANALYSIS IN CIVIL ENGINEERING MATERIAL TESTING". ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-2/W18 (29.11.2019): 107–13. http://dx.doi.org/10.5194/isprs-archives-xlii-2-w18-107-2019.

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Abstract. This publication concentrates on the photogrammetric crack width measurement of crack patterns of concrete probes under impact loading in high-speed stereo image sequences. The presented algorithm works for non-planar specimens with deformations that only appear tangential to the surface and the method is based on triangle mesh analysis. Experiments were conducted with cylindrical specimens with an impact load affecting parallel to the main axis of the cylinder.

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Nikitin, Victor V., Sergey Valer'evich Gulin i Eugene G. Sereda. "Speed and position detecting systems for vehicle with linear synchronous motors". Transportation systems and technology 1, nr 2 (15.12.2015): 85–99. http://dx.doi.org/10.17816/transsyst20151285-99.

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In high-speed ground transport linear synchronous motors are used to create a traction force. Advantages of linear synchronous motors are precise control of traction force (does not depend on friction forces) and lack of wearing parts. Linear synchronous motors control systems use block diagrams with orientation on rotor flux linkage. In such systems, information about exact position of movable part allows splitting active and reactive components of stator currents and as result independent control of motor traction force and magnetic flux. Errors in determination position can lead to errors in d-q transformation what affect calculations performed in motor model, and impact on traction force. Moreover, information on position of vehicle is also important to ensure traffic safety. In conventional types of wheeled vehicles for determining speed and position contact probes and tachometers are used. However, in high-speed magnetic levitation transport non-contact sensors is needed. In addition, when creating control system delay in transmission of radio signals from vehicle to ground control unit should be taken into account. This paper revive methods of speed and location detection for industry and high-speed ground transportation systems with linear synchronous motors. Also, variant of speed and position detection system for freight Maglev was suggested.

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Lepicovsky, Jan. "On Directional Sensitivity of Thermo-Anemometer Split-Fiber Probes". E3S Web of Conferences 345 (2022): 01010. http://dx.doi.org/10.1051/e3sconf/202234501010.

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Hot-wire thermo-anemometer probes are extremely fragile and they are used mostly in clean flows with neither debris nor small particles to prevent sensor destruction. Consequently, application of hot-wire probes is limited mostly to clean laboratory environments, their employment in semi-industrial research is extremely rare, and not always successful. Film probes with deposited thin metallic sensors on cylindrical fibers are more rugged and can be successfully employed for research tasks in semi-industrial environment. Surprisingly the potentials of these probes are not yet fully utilized. Detailed investigation of direction characteristics of a split-fiber probe was carried out during the course of this work. Several interesting outcomes resulted from this study. First, it has been shown that the split-fiber probe direction sensitivity rises with the increasing velocity contrary to the decrease of the velocity sensitivity, which is a common hindrance to application of single-sensor thermo-probes to high-speed and transonic flows. Second, the analysis of the acquired data revealed a sudden shift in the effective zero angle offset. It can be speculated that such a shift can related to the transition of the laminar vortex street into the turbulent one. However, the observed shift occurred at Reynolds number values between 900 and 1000, which is markedly higher than the usually reported transitional Reynolds number range between 150 and 300. Finally, the resilience of split-fiber probes to impairment by in-flow debris has been demonstrated proving the probe ability for effective use of these probes in semi-industrial or even industrial research tasks.

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Moffett, Mark B., David L. Chesny, Jake M. Cole, Kaleb W. Hatfield i Razvan Rusovici. "Bdot probe and Rogowski coil cross-calibration and sensor fusion in pulsed direct current capacitor discharges". Review of Scientific Instruments 93, nr 3 (1.03.2022): 034707. http://dx.doi.org/10.1063/5.0076741.

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Bdot probes and Rogowski coils are used in the measurement of transient magnetic fields and currents, respectively. They both share the mechanism of creating an induced electromotive force response via Faraday’s law, which scales linearly with the pulsed magnetic field. High power capacitor direct current (DC) discharge systems release a single pulse of current that is both very high and very fast (≲1 ms). To capture these transient data and characterize these systems, high current tolerant and fast response time sensors are required. While these measuring devices have been well studied and utilized for almost 100 years, a comprehensive and detailed description of the custom design, calibration, and sensor fusion application of these tools for use in various pulsed DC capacitor value discharges is largely missing in the literature. Using robust analytical calculations, finite element analyses, and empirical methods, we have developed a sensor fusion protocol for current and magnetic field probes (with relative errors of ±13% and ±15%, respectively) for use in any geometry of high speed pulsed DC current calibrated capacitor discharge systems. This paper comprehensively outlines the design and sensor fusion methodologies that allow for the deployment of in-house built Bdot probes and Rogowski coils to a wide range of pulsed DC systems and demonstrates their use in a characteristic plasma environment.

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Kunicki, Angelov, Ivanov, Gotszalk i Rangelow. "Sensitivity Improvement to Active Piezoresistive AFM Probes Using Focused Ion Beam Processing". Sensors 19, nr 20 (12.10.2019): 4429. http://dx.doi.org/10.3390/s19204429.

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This paper presents a comprehensive modeling and experimental verification of active piezoresistive atomic force microscopy (AFM) cantilevers, which are the technology enabling high-resolution and high-speed surface measurements. The mechanical structure of the cantilevers integrating Wheatstone piezoresistive was modified with the use of focused ion beam (FIB) technology in order to increase the deflection sensitivity with minimal influence on structure stiffness and its resonance frequency. The FIB procedure was conducted based on the finite element modeling (FEM) methods. In order to monitor the increase in deflection sensitivity, the active piezoresistive cantilever was deflected using an actuator integrated within, which ensures reliable and precise assessment of the sensor properties. The proposed procedure led to a 2.5 increase in the deflection sensitivity, which was compared with the results of the calibration routine and analytical calculations.

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Zhou, Wei, Aliyu Kasimu, Yitong Wu, Mingzan Tang, Xifeng Liang i Chen Jiang. "Wind Speed Measurement via Visual Recognition of Wind-Induced Waving Light Stick Target". Applied Sciences 13, nr 9 (25.04.2023): 5375. http://dx.doi.org/10.3390/app13095375.

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Wind measurement in confined spaces is a challenge due to the influence of the dimensions of anemometers in intrusive flow-field measurements where the anemometer probes directly contact and influence the near-probe flow field. In this work, a new wind speed detection methodology is proposed based on wind-induced motion of a stick via vision-based recognition. The target’s displacement in pixel coordinates is mapped to its angular displacement in world coordinates to derive wind speed and direction information by applying the calibration coefficients. Simulation experiments were carried out to validate the model, the error of which was within an angular displacement of 4.0° and 3.0° for wind speed and direction detections, respectively. When applied to the measurement of wind speed in the inner equipment cabin of a stationary high-speed train, the error was within ±1.1 m/s in terms of average RMSE. Thus, the proposed method provides an accurate and economic option for monitoring 2D wind in a confined space.

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