Journal articles: 'Laser Profiler'

1

Chu, An-Shyang, and M. A. Butler. "Laser surface profiler." Optics Letters 24, no. 7 (April 1, 1999): 457. http://dx.doi.org/10.1364/ol.24.000457.

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Sezen, Halil, and Nicholas Fisco. "EVALUATION AND COMPARISON OF SURFACE MACROTEXTURE AND FRICTION MEASUREMENT METHODS." Journal of Civil Engineering and Management 19, no. 3 (June 14, 2013): 387–99. http://dx.doi.org/10.3846/13923730.2012.746237.

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Two- and three-dimensional macrotexture characteristics of various surfaces were measured using five different testing methods including sand patch method, laser profiler, laser texture scanner, circular texture meter, and x-ray computed tomography (CT) scanning. A dynamic friction tester was also used to measure the friction resistance of the same surfaces. Asphalt and Portland cement concrete samples of various mix designs and finishes and other commonly manufactured textured samples were used. Relationship between the macrotexture and friction was investigated. Mean texture depth (MTD) of 26 laboratory specimens was obtained from volumetric sand patch tests. Two-dimensional profiles and mean profile depth (MPD) of specimens were measured by a laser profiler. A laser texture scanner and a circular texture meter were also used to calculate the MPD of sample surfaces. Three-dimensional rendering of the surfaces were obtained from laser texture scanner and x-ray CT scans. Using the experimental data collected in this study, relationships between friction resistance and macrotexture obtained from different methods were investigated. The estimated texture depths predicted from laser profiler, laser texture scanner, and CT meter were comparable to the MTD obtained from sand patch tests. Also, the friction resistance increased with increasing surface macrotexture.

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Hossain, Md Arafat, John Canning, Kevin Cook, and Abbas Jamalipour. "Smartphone laser beam spatial profiler." Optics Letters 40, no. 22 (November 2, 2015): 5156. http://dx.doi.org/10.1364/ol.40.005156.

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Perera, Rohan W., Starr D. Kohn, and Sohila Bemanian. "Comparison of Road Profilers." Transportation Research Record: Journal of the Transportation Research Board 1536, no. 1 (January 1996): 117–24. http://dx.doi.org/10.1177/0361198196153600117.

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Devices available to measure road profiles vary from the hand-held Dipstick to high-speed, vehicle-based profilers. High-speed, vehicle-based profilers generally use an ultrasonic, laser, or optical measuring system. A profiler calibration study was conducted by the road profiler user group in 1994 by establishing regional calibration centers in Mississippi, Nevada, Pennsylvania, and South Dakota. The study compared the data collected by the profilers with the Dipstick data, and analyzed the effect of surface texture on data collection. At each regional calibration center, asphalt concrete and portland cement concrete test sections were established. Thirty-eight road profilers belonging to state agencies, equipment manufacturers, and FHWA participated in the calibration study. Dipstick measurements and sand-patch tests were conducted at all test sites. The International Roughness Index (IRI) was used as the parameter for performing the analyses. The results of the analyses for the sites in Pennsylvania and South Dakota are presented. The agreement between Dipstick IRI and profiler IRI for a specific profiler varied from site to site. For a specific profiler at some sites, the agreement with the Dipstick IRI was good, while at other sites the agreement was poor. The profilers with ultrasonic measuring systems generally had poor agreement with Dipstick IRI values for asphalt-surfaced sites that had aggregate seal coats.

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Borelli, Noah, Bouzid Choubane, James Greene, Charles Holzschuher, and James Fletcher. "Cross-Correlation Analysis of Line Laser High-speed Inertial Profilers." Transportation Research Record: Journal of the Transportation Research Board 2674, no. 5 (May 2020): 626–36. http://dx.doi.org/10.1177/0361198120917371.

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Thirteen different line-laser high-speed inertial profilers from four different manufacturers were recently tested at the Florida Department of Transportation (FDOT) Inertial Profiler Test Track. The hot-mix asphalt (HMA) track incorporates both dense and open-graded sections with international roughness index (IRI) values ranging from 34 to 104 in./mi. A cross-correlation analysis was performed on the resulting ride data. The accuracy comparison was performed using a SurPro reference profiler. The profilers as a group met the AASHTO R 56 cross-correlation criteria on each section except on a smooth, open-graded section. The profilers as a group met the repeatability cross-correlation on this section, but did not meet the accuracy cross-correlation requirement. This paper presents a description of the testing program, data collection efforts and subsequent analyses and findings.

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Mandlburger, G., M. Pfennigbauer, M. Wieser, U. Riegl, and N. Pfeifer. "EVALUATION OF A NOVEL UAV-BORNE TOPO-BATHYMETRIC LASER PROFILER." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B1 (June 6, 2016): 933–39. http://dx.doi.org/10.5194/isprs-archives-xli-b1-933-2016.

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We present a novel topo-bathymetric laser profiler. The sensor system (RIEGL BathyCopter) comprises a laser range finder, an Inertial Measurement Unit (IMU), a Global Navigation Satellite System (GNSS) receiver, a control unit, and digital cameras mounted on an octocopter UAV (RiCOPTER). The range finder operates on the time-of-flight measurement principle and utilizes very short laser pulses (<1 ns) in the green domain of the spectrum (λ=532 nm) for measuring distances to both the water surface and the river bottom. For assessing the precision and accuracy of the system an experiment was carried out in October 2015 at a pre-alpine river (Pielach in Lower Austria). A 200 m longitudinal section and 12 river cross sections were measured with the BathyCopter sensor system at a flight altitude of 15-20 m above ground level and a measurement rate of 4 kHz. The 3D laser profiler points were compared with independent, quasi-simultaneous data acquisitions using (i) the RIEGL VUX1-UAV lightweight topographic laser scanning system (bare earth, water surface) and (ii) terrestrial survey (river bed). Over bare earth the laser profiler heights have a std. dev. of 3 cm, the water surface height appears to be underestimated by 5 cm, and river bottom heights differ from the reference measurements by 10 cm with a std. dev. of 13 cm. When restricting the comparison to laser profiler bottom points and reference measurements with a lateral offset below 1 m, the values improve to 4 cm bias with a std. dev. of 6 cm. We report additionally on challenges in comparing UAV-borne to terrestrial profiles. Based on the accuracy and the small footprint (3.5 cm at the water surface) we concluded that the acquired 3D points can potentially serve as input data (river bed geometry, grain roughness) and validation data (water surface, water depth) for hydrodynamic-numerical models.

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Mandlburger, G., M. Pfennigbauer, M. Wieser, U. Riegl, and N. Pfeifer. "EVALUATION OF A NOVEL UAV-BORNE TOPO-BATHYMETRIC LASER PROFILER." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B1 (June 6, 2016): 933–39. http://dx.doi.org/10.5194/isprsarchives-xli-b1-933-2016.

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We present a novel topo-bathymetric laser profiler. The sensor system (RIEGL BathyCopter) comprises a laser range finder, an Inertial Measurement Unit (IMU), a Global Navigation Satellite System (GNSS) receiver, a control unit, and digital cameras mounted on an octocopter UAV (RiCOPTER). The range finder operates on the time-of-flight measurement principle and utilizes very short laser pulses (<1 ns) in the green domain of the spectrum (λ=532 nm) for measuring distances to both the water surface and the river bottom. For assessing the precision and accuracy of the system an experiment was carried out in October 2015 at a pre-alpine river (Pielach in Lower Austria). A 200 m longitudinal section and 12 river cross sections were measured with the BathyCopter sensor system at a flight altitude of 15-20 m above ground level and a measurement rate of 4 kHz. The 3D laser profiler points were compared with independent, quasi-simultaneous data acquisitions using (i) the RIEGL VUX1-UAV lightweight topographic laser scanning system (bare earth, water surface) and (ii) terrestrial survey (river bed). Over bare earth the laser profiler heights have a std. dev. of 3 cm, the water surface height appears to be underestimated by 5 cm, and river bottom heights differ from the reference measurements by 10 cm with a std. dev. of 13 cm. When restricting the comparison to laser profiler bottom points and reference measurements with a lateral offset below 1 m, the values improve to 4 cm bias with a std. dev. of 6 cm. We report additionally on challenges in comparing UAV-borne to terrestrial profiles. Based on the accuracy and the small footprint (3.5 cm at the water surface) we concluded that the acquired 3D points can potentially serve as input data (river bed geometry, grain roughness) and validation data (water surface, water depth) for hydrodynamic-numerical models.

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8

Laguarta, F., I. Al-Khatib, and R. Artigas. "Laser profiler based on the depth from focus principle." Journal of Optics 29, no. 3 (June 1998): 236–40. http://dx.doi.org/10.1088/0150-536x/29/3/025.

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9

McIvor, Alan M. "Nonlinear calibration of a laser stripe profiler." Optical Engineering 41, no. 1 (January 1, 2002): 205. http://dx.doi.org/10.1117/1.1416694.

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10

Kolchinskiy, Vladislav, Cheng-Hung Shih, Ikai Lo, and Roman Romashko. "Refractive Index Measurement Using the Laser Profiler." Physics Procedia 86 (2017): 176–80. http://dx.doi.org/10.1016/j.phpro.2017.01.018.

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11

Yan, Jianguo, Chunguang Wang, Shengshi Xie, and Lijuan Wang. "DESIGN AND VALIDATION OF A SURFACE PROFILING APPARATUS FOR AGRICULTURAL TERRAIN ROUGHNESS MEASUREMENTS." INMATEH Agricultural Engineering 59, no. 3 (December 20, 2019): 169–80. http://dx.doi.org/10.35633/inmateh-59-19.

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How to accurately and efficiently measure the profiles of the terrain on which agricultural machines operate has been an ongoing research topic. In this study, a surface profiling apparatus (profiler) was developed to measure agricultural terrain profiles along parallel tracks. The profiler is mainly composed of sensor frames, an RTK-GNSS system (Real Time Kinematics-Global Navigation Satellite Systems), laser sensors, an Inertial Measurement Unit (IMU) sensor and a data acquisition system. Along with a full description of how the terrain profiles were produced, a methodology to compensate for the tractor motion was included in the sensor data analysis. In field profiling validation, two trapezoidal bumps with known dimensions were used to assess the ability of the terrain profiler to reproduce the vertical profiles of the bumps, resulting in root mean square error (RMSE) of 3.6-4.7 mm and 4.5-5.1 mm with profiling speeds of 1.02 and 2.56 km/h, respectively. In addition, a validation test was also conducted on an asphalt road by profiling a flat road with the measuring wheels of the profiler rolling on the flat section but with the tractor wheels driving over a trapezoidal bump to excite the tractor pitch and roll motion. The measured profiles then also exhibited a flat road, which showed the ability of the profiler to remove the tractor motion from the profiling measurements.

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12

大垣, 正雄, and 伸二涌井. "Development of Beam Profiler for Laser Light Sheet." 産業応用工学会論文誌 4, no. 2 (2016): 37–44. http://dx.doi.org/10.12792/jjiiae.004.02.02.

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13

Schwind, K. M., E. Aktan, R. Prasad, M. Cerchez, D. Eversheim, O. Willi, and B. Aurand. "An online beam profiler for laser-accelerated protons." Review of Scientific Instruments 90, no. 5 (May 2019): 053307. http://dx.doi.org/10.1063/1.5086248.

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14

Liu, Shuang, Zongjun Tian, Lida Shen, and Mingbo Qiu. "Numerical Simulation and Experimental Investigation of Laser Ablation of Al2O3 Ceramic Coating." Materials 13, no. 23 (December 2, 2020): 5502. http://dx.doi.org/10.3390/ma13235502.

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This paper presents an evaluation of the molten pool laser damage done to an Al2O3 ceramic coating. Mechanism analysis of the laser damage allowed for a 2D finite element model of laser ablation of the Al2O3 ceramic coating to be built. It consisted of heat transfer, laminar flow, and a solid mechanics module with the level set method. Results showed that the laser damage mechanisms through laser ablation were melting, gasification, spattering, and micro-cracking. The ablation depth and diameter increased with the increasing laser ablation time under continuous irradiation. The simulation profile was consistent with the experimental one. Additionally, the stress produced by the laser ablation was 3500–9000 MPa, which exceeded the tensile stress (350–500 MPa), and fracturing and micro-cracks occurred. Laser damage analysis was performed via COMSOL Multiphysics to predict laser damage morphology, and validate the 3D surface profiler and scanning electron microscope results.

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15

Nadkarni, Seemantini. "Comprehensive Coagulation Profiling at the Point-of-Care Using a Novel Laser-Based Approach." Seminars in Thrombosis and Hemostasis 45, no. 03 (March 18, 2019): 264–74. http://dx.doi.org/10.1055/s-0039-1683842.

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AbstractDelays in identifying internal bleeding are life-threatening, thus underscoring the need for rapid and comprehensive coagulation profiling at the bedside. The authors review a novel optical coagulation profiler that measures several coagulation metrics including prothrombin time, activated clotting time, clot polymerization rate (α-angle), clot stiffness (maximum amplitude), fibrinolysis (LY), and platelet function, using a single multifunctional instrument. The optical profiler is based on the principles of Laser Speckle Rheology that quantifies tissue viscoelasticity from light scattering patterns called laser speckle. To operate the optical profiler, whole blood (40 μL) is loaded into a disposable cartridge, laser speckle patterns are recorded via a camera, and the viscoelasticity of clotting blood is estimated from speckle intensity fluctuations. By monitoring alterations in viscoelastic moduli over time during clot initiation, thrombin generation, fibrin crosslinking, clot stabilization, and LY, global coagulation parameters are obtained within 10 minutes using a drop of whole blood. Clinical testing in over 500 patients to date has confirmed the accuracy of the optical profiler for comprehensively assessing coagulation status against conventional coagulation tests and thromboelastography. Recent studies have further demonstrated the capability to quantify platelet aggregation induced by adenosine diphosphate in a drop of platelet-rich-plasma in the absence of applied shear stress. Together, these studies demonstrate that global coagulation profiling in addition to platelet function may be accomplished using a single multifunctional device. Thus, by enabling rapid and comprehensive coagulation and platelet function profiling at the bedside, the optical profiler will likely advance the capability to identify and manage patients with an elevated risk for hemorrhage.

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Wen, Bo, Sho Sekine, Shinichi Osawa, Yuki Shimizu, Hiraku Matsukuma, Andreas Archenti, and Wei Gao. "A Comparison of the Probes with a Cantilever Beam and a Double-Sided Beam in the Tool Edge Profiler for On-Machine Measurement of a Precision Cutting Tool." Machines 9, no. 11 (November 6, 2021): 271. http://dx.doi.org/10.3390/machines9110271.

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This paper describes a comparison of the mechanical structures (a double-sided beam and a cantilever beam) of a probe in a tool edge profiler for the measurement of a micro-cutting tool. The tool edge profiler consists of a positioning unit having a pair of one-axis DC servo motor stages and a probe unit having a laser displacement sensor and a probe composed of a stylus and a mechanical beam; on-machine measurement of a tool cutting edge can be conducted with a low contact force through measuring the deformation of the probe by the laser displacement sensor while monitoring the tool position. Meanwhile, the mechanical structure of the probe could affect the performance of measurement of the edge profile of a precision cutting tool. In this paper, the measurement principle of the tool edge profile is firstly introduced; after that, slopes and a top-flat of a cutting tool sample are measured by using a cantilever-type probe and a double-sided beam-type probe, respectively. The measurement performances of the two probes are compared through experiments and theoretical measurement uncertainty analysis.

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Fisco, Nicholas, and Halil Sezen. "COMPARISON OF SURFACE MACROTEXTURE MEASUREMENT METHODS." Journal of Civil Engineering and Management 19, Supplement_1 (January 9, 2014): S153—S160. http://dx.doi.org/10.3846/13923730.2013.802732.

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Recent advances in technology allowed for the use of laser-based systems that can directly measure macrotexture properties of various surfaces. Volumetric or sand patch method has historically been used as the main technique for measuring macrotexture. Different available methods do not all measure the same surface properties and often generate different measurements. Thus, it is crucial to determine the most suitable method for measuring surface macrotexture. This paper investigates mean profile depth measurements from three laser based macrotexture measuring devices, including a laser profiler, a laser texture scanner and a circular texture meter. The results are compared with mean texture depth obtained from volumetric sand patch tests. Experiments were conducted to measure macrotexture of 26 laboratory specimens, which included asphalt and Portland cement concrete samples of various type and finish, as well as other common manufactured textured samples. Based on the evaluation of experimental data collected in this study, relationships are recommended to predict standard macrotexture using the mean profile depth data measured by a laser equipment or scanner.

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Steinbuck, Jonah V., Paul L. D. Roberts, Cary D. Troy, Alexander R. Horner-Devine, Fernando Simonet, Alfred H. Uhlman, Jules S. Jaffe, Stephen G. Monismith, and Peter J. S. Franks. "An Autonomous Open-Ocean Stereoscopic PIV Profiler." Journal of Atmospheric and Oceanic Technology 27, no. 8 (August 1, 2010): 1362–80. http://dx.doi.org/10.1175/2010jtecho694.1.

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Abstract Over the past decade, a novel free-fall imaging profiler has been under development at the Scripps Institution of Oceanography to observe and quantify biological and physical structure in the upper 100 m of the ocean. The profiler provided the first detailed view of microscale phytoplankton distributions using in situ planar laser-induced fluorescence. The present study examines a recent incarnation of the profiler that features microscale turbulent flow measurement capabilities using stereoscopic particle image velocimetry (PIV). As the profiler descends through the water column, a vertical sheet of laser light illuminates natural particles below the profiler. Two sensitive charge-coupled device (CCD) cameras image a 25 cm × 25 cm × 0.6 cm region at a nominal frame rate of 8 Hz. The stereoscopic camera configuration allows all three components of velocity to be measured in the vertical plane with an average spatial resolution of approximately 3 mm. The performance of the PIV system is evaluated for deployments offshore of the southern California coast. The in situ image characteristics, including natural particle seeding density and imaged particle size, are found to be suitable for PIV. Ensemble-averaged velocity and dissipation of turbulent kinetic energy estimates from the stereoscopic PIV system are consistent with observations from an acoustic Doppler velocimeter and acoustic Doppler current profiler, though it is revealed that the present instrument configuration influences the observed flow field. The salient challenges in adapting stereoscopic PIV for in situ, open-ocean turbulence measurements are identified, including cross-plane particle motion, instrument intrusiveness, and measurement uncertainty limitations. These challenges are discussed and recommendations are provided for future development: improved alignment with the dominant flow direction, mitigation of instrument intrusiveness, and improvements in illumination and imaging resolution.

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Hong, Seong Jae, Tak Jib Hyun, Hyung Bae Kim, Oh Sun Kwon, and Seung Woo Lee. "A Study on the Measurement of Texture Depth of Pavement Using Portable Laser Profiler." Journal of the Korean Society of Road Engineers 14, no. 6 (December 17, 2012): 45–55. http://dx.doi.org/10.7855/ijhe.2012.14.6.045.

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Nazal, Nurul Asha Mohd, Daryl Tan, Kok-Sing Lim, Hang-Zhou Yang, and Harith Ahmad. "Regenerated Chirped Grating-Michelson Interferometer as a Laser Beam Intensity Profiler for CO2 Laser." IEEE Transactions on Instrumentation and Measurement 69, no. 2 (February 2020): 559–64. http://dx.doi.org/10.1109/tim.2019.2901560.

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Schein, J., K. M. Campbell, R. R. Prasad, R. Binder, and M. Krishnan. "Radiation hard diamond laser beam profiler with subnanosecond temporal resolution." Review of Scientific Instruments 73, no. 1 (January 2002): 18–22. http://dx.doi.org/10.1063/1.1424904.

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Ota, Taisuke. "Laser focal profiler based on forward scattering of a nanoparticle." Optics Communications 411 (March 2018): 59–64. http://dx.doi.org/10.1016/j.optcom.2017.10.066.

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Pershin, Sergey M., Boris G. Katsnelson, Mikhail Ya Grishin, Vasily N. Lednev, Vladimir A. Zavozin, and Ilia Ostrovsky. "Laser Remote Sensing of Lake Kinneret by Compact Fluorescence LiDAR." Sensors 22, no. 19 (September 26, 2022): 7307. http://dx.doi.org/10.3390/s22197307.

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Harmful algal blooms in freshwater reservoirs became a steady phenomenon in recent decades, so instruments for monitoring water quality in real time are of high importance. Modern satellite remote sensing is a powerful technique for mapping large areas but cannot provide depth-resolved data on algal concentrations. As an alternative to satellite techniques, laser remote sensing is a perspective technique for depth-resolved studies of fresh or seawater. Recent progress in lasers and electronics makes it possible to construct compact and lightweight LiDARs (Light Detection and Ranging) that can be installed on small boats or drones. LiDAR sensing is an established technique; however, it is more common in studies of seas rather than freshwater reservoirs. In this study, we present an experimental verification of a compact LiDAR as an instrument for the shipborne depth profiling of chlorophyll concentration across the freshwater Lake Kinneret (Israel). Chlorophyll depth profiles of 3 m with a 1.5 m resolution were measured in situ, under sunlight conditions. A good correlation (R2 = 0.89) has been established between LiDAR signals and commercial algae profiler data. A non-monotonic algae depth distribution was observed along the boat route during daytime (Tiberias city–Jordan River mouth–Tiberias city). The impact of high algal concentration on water temperature laser remote sensing has been studied in detail to estimate the LiDAR capability of in situ simultaneous measurements of temperature and chlorophyll concentration.

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Martan, Jiří, Denys Moskal, Ladislav Smeták, and Milan Honner. "Performance and Accuracy of the Shifted Laser Surface Texturing Method." Micromachines 11, no. 5 (May 20, 2020): 520. http://dx.doi.org/10.3390/mi11050520.

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A shifted laser surface texturing method (sLST) was developed for the improvement of the production speed of functional surface textures to enable their industrial applicability. This paper compares the shifted method to classic methods using a practical texturing example, with a focus on delivering the highest processing speed. The accuracy of the texture is assessed by size and circularity measurements with the use of LabIR paint and by a depth profile measurement using a contact surface profiler. The heat accumulation temperature increase and laser usage efficiency were also calculated. The classic methods (path filling and hatch) performed well (deviation ≤ 5%) up to a certain scanning speed (0.15 and 0.7 m/s). For the shifted method, no scanning speed limit was identified within the maximum of the system (8 m/s). The depth profile shapes showed similar deviations (6% to 10%) for all methods. The shifted method in its burst variant achieved the highest processing speed (11 times faster, 146 mm2/min). The shifted method in its path filling variant achieved the highest processing efficiency per needed laser power (64 mm2/(min·W)), lowest heat accumulation temperature increase (3 K) and highest laser usage efficiency (99%). The advantages of the combination of the shifted method with GHz burst machining and the multispot approach were described.

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Lacroix, P., B. Legrésy, K. Langley, S. E. Hamran, J. Kohler, S. Roques, F. Rémy, and M. Dechambre. "In situ measurements of snow surface roughness using a laser profiler." Journal of Glaciology 54, no. 187 (2008): 753–62. http://dx.doi.org/10.3189/002214308786570863.

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AbstractThe snow surface roughness at centimetre and millimetre scales is an important parameter related to wind transport, snowdrifts, snowfall, snowmelt and snow grain size. Knowledge of the snow surface roughness is also of high interest for analyzing the signal from radar sensors such as SAR, altimeters and scatterometers. Unfortunately, this parameter has seldom been measured over snow surfaces. The techniques used to measure the roughness of other surfaces, such as agricultural or sand soils, are difficult to implement in polar regions because of the harsh climatic conditions. In this paper we develop a device based on a laser profiler coupled with a GPS receiver on board a snowmobile. This instrumentation was tested successfully in midre Lovénbreen, Svalbard, in April 2006. It allowed us to generate profiles of 3 km sections of the snow-covered glacier surface. Because of the motion of the snowmobile, the roughness signal is mixed with the snowmobile signal. We use a distance/frequency analysis (the empirical mode decomposition) to filter the signal. This method allows us to recover the snow surface structures of wavelengths between 4 and 50 cm with amplitudes of >1 mm. Finally, the roughness parameters of snow surfaces are retrieved. The snow surface roughness is found to be dependent on the scales of the observations. The retrieved RMS of the height distribution is found to vary between 0.5 and 9.2 mm, and the correlation length is found to be between 0.6 and 46 cm. This range of measurements is particularly well adapted to the analysis of GHz radar response on snow surfaces.

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HIRAOKA, Toru, and Hirofumi NONAKA. "Correlation Analysis of Total Coliform and Entropy of Laser Profiler Data." Journal of the Japan society of photogrammetry and remote sensing 52, no. 6 (2013): 316–20. http://dx.doi.org/10.4287/jsprs.52.316.

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Dover, N. P., M. Nishiuchi, H. Sakaki, M. A. Alkhimova, A. Ya Faenov, Y. Fukuda, H. Kiriyama, et al. "Scintillator-based transverse proton beam profiler for laser-plasma ion sources." Review of Scientific Instruments 88, no. 7 (July 2017): 073304. http://dx.doi.org/10.1063/1.4994732.

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Shibata, Yasukuni, Nagasawa Chikao, and Makoto Abo. "Observations of The Lower-Tropospheric Temperature Profiles Using Three Wavelength CO2-DIAL." EPJ Web of Conferences 237 (2020): 03021. http://dx.doi.org/10.1051/epjconf/202023703021.

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The eye-safe lower-tropospheric temperature profiler with three wavelength differential absorption lidar (DIAL) technique which can perform the continuous temperature profile observation through daytime and nighttime is conducted. The DIAL consists of a Nd:YAG laser pumped an OPG tuned around 1573 nm of an CO2 absorption line with 2 mJ/pulse at 400 Hz repetition rate and a receiving telescope of 25cm diameter. In this paper, we show the result of continuous temperature profile observations over 25 hours from 0.39 to 2.5 km altitude in the lower-troposphere. We can see temporally the generation and disappearance of the temperature inversion layers in the planetary boundary layer.

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Yin, Jie, Zhen Yu Zhao, Hou Ming Zhou, Kai Li, and Hao Zhou. "Numerical Simulation of the Influence of Different Surface Morphologies on Molten Pool Flow under Moving Heat Source." Key Engineering Materials 904 (November 22, 2021): 9–13. http://dx.doi.org/10.4028/www.scientific.net/kem.904.9.

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In order to study the influence of different initial topography on the molten pool flow under a moving heat source, the finite element analysis method was used to establish a two-dimensional transient model of laser polishing to simulate the evolution of the surface topography of the material during laser polishing. In the simulation process, a moving laser beam was used as the heat source, and the free surface of the actual material was profiled through a three-dimensional profiler. A very similar simulation model surface was constructed, coupled with the flow field and temperature field in the laser polishing process, and the capillary force was considered comprehensively. Combined with thermocapillary force. The results show that under the combined action of capillary force and thermocapillary force, the surface of the polished material has a peak-filling effect, which makes the surface of the material achieve a good polishing effect. The initial shape will affect the polishing effect, the greater the curvature, the faster the flow rate of the molten pool. In molten pools with large spatial curvatures, capillary forces dominate. Keywords: Laser polishing; molten pool; surface topography; numerical analysis; capillary force; thermocapillary force.

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Heinz, Erik, Markus Mettenleiter, Heiner Kuhlmann, and Christoph Holst. "Strategy for Determining the Stochastic Distance Characteristics of the 2D Laser Scanner Z + F Profiler 9012A with Special Focus on the Close Range." Sensors 18, no. 7 (July 12, 2018): 2253. http://dx.doi.org/10.3390/s18072253.

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Kinematic laser scanning with moving platforms has been used for the acquisition of 3D point clouds of our environment for many years. A main application of these mobile systems is the acquisition of the infrastructure, e.g., the road surface and buildings. Regarding this, the distance between laser scanner and object is often notably shorter than 20 m. In the close range, however, divergent incident laser light can lead to a deterioration of the precision of laser scanner distance measurements. In the light of this, we analyze the distance precision of the 2D laser scanner Z + F Profiler 9012A, purpose-built for kinematic applications, in the range of up to 20 m. In accordance with previous studies, a clear dependency between scan rate, intensity of the backscattered laser light and distance precision is evident, which is used to derive intensity-based stochastic models for the sensor. For this purpose, a new approach for 2D laser scanners is proposed that is based on the static scanning of surfaces with different backscatter. The approach is beneficial because the 2D laser scanner is operated in its normal measurement mode, no sophisticated equipment is required and no model assumptions for the scanned surface are made. The analysis reveals a lower precision in the range below 5 m caused by a decreased intensity. However, the Z + F Profiler 9012A is equipped with a special hardware-based close range optimization partially compensating for this. Our investigations show that this optimization works best at a distance of about 2 m. Although increased noise remains a critical factor in the close range, the derived stochastic models are also valid below 5 m.

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Gkyrtis, Konstantinos, Andreas Loizos, and Christina Plati. "Integrating Pavement Sensing Data for Pavement Condition Evaluation." Sensors 21, no. 9 (April 29, 2021): 3104. http://dx.doi.org/10.3390/s21093104.

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Highway pavements are usually monitored in terms of their surface performance assessment, since the major cause that triggers maintenance is reduced pavement serviceability due to surface distresses, excessive pavement unevenness and/or texture loss. A common way to detect pavement surface condition is by the use of vehicle-mounted laser sensors that can rapidly scan huge roadway networks at traffic speeds without the need for traffic interventions. However, excessive roughness might sometimes indicate structural issues within one or more pavement layers or even issues within the pavement foundation support. The stand-alone use of laser profilers cannot provide the related agencies with information on what leads to roughness issues. Contrariwise, the integration of multiple non-destructive data leads to a more representative assessment of pavement condition and enables a more rational pavement management and decision-making. This research deals with an integration approach that primarily combines pavement sensing profile and deflectometric data and further evaluates indications of increased pavement roughness. In particular, data including Falling Weight Deflectometer (FWD) and Road Surface Profiler (RSP) measurements are used in conjunction with additional geophysical inspection data from Ground Penetrating Radar (GPR). Based on pavement response modelling, a promising potential is shown that could proactively assist the related agencies in the framework of transport infrastructure health monitoring.

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Wei, X., X. Z. Xie, W. Hu, and J. F. Huang. "Polishing Sapphire Substrates by 355 nm Ultraviolet Laser." International Journal of Optics 2012 (2012): 1–7. http://dx.doi.org/10.1155/2012/238367.

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This paper tries to investigate a novel polishing technology with high efficiency and nice surface quality for sapphire crystal that has high hardness, wear resistance, and chemical stability. A Q-switched 355 nm ultraviolet laser with nanosecond pulses was set up and used to polish sapphire substrate in different conditions in this paper. Surface roughnessRaof polished sapphire was measured with surface profiler, and the surface topography was observed with scanning electronic microscope. The effects of processing parameters as laser energy, pulse repetition rate, scanning speed, incident angle, scanning patterns, and initial surface conditions on surface roughness were analyzed.

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Xue, Wenjing, Gerardo W. Flintsch, and Brian K. Diefenderfer. "Measuring Pavement Permanent Deformation in Accelerated Pavement Testing." Transportation Research Record: Journal of the Transportation Research Board 2674, no. 5 (April 23, 2020): 340–48. http://dx.doi.org/10.1177/0361198120915471.

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Permanent deformation is an essential criterion for evaluating pavement performance. In an accelerated pavement testing (APT) experiment at the Virginia Tech Transportation Institute, a laser profiler, multi-depth deflectometer (MDD), and forensic investigation were used to measure the permanent deformation of a pavement system. This paper analyzes the permanent deformation measured via the three methods during the APT experiment. The major concern among the three methods is applicability rather than accuracy. To measure surface deformation, the laser profiler is a more practical method than MDD in APT, as it can scan the whole surface instead of just one point. To measure the deformation within a pavement structure, MDD provides deformation development throughout the whole experiment, which is helpful for a deeper understanding of pavement materials and structures. However, MDD is also more expensive and requires significant installation effort and maintenance during the experiment compared with forensic investigation, which also needs to be considered.

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Borrmann, D., S. Jörissen, and A. Nüchter. "RADLER – A UNICYCLE AS A LOW-COST RADIAL LASER SCANNER." ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences V-1-2021 (June 17, 2021): 65–72. http://dx.doi.org/10.5194/isprs-annals-v-1-2021-65-2021.

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Abstract. In recent years a wide range of 3D multi sensor systems for various applications has been proposed. Each of them has its own benefits and limitations. This paper proposes a modified unicycle with a 2D laser profiler attached to the wheel axle, thus creating a radial 3D scanning pattern. This novel low-cost device combines the advantages of wheeled scanning equipment with those of wearable or hand-held devices. After presenting the hardware setup and the sensor integration, the results are evaluated using four test scenarios and a terrestrial laser scanner for comparison.

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Ratanavis, Amarin. "A single-slit diffraction experiment for measuring laser beam width." Physics Education 57, no. 3 (March 4, 2022): 035007. http://dx.doi.org/10.1088/1361-6552/ac4c01.

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Abstract A single-slit diffraction experiment in an introductory physics laboratory is generally comprised of a rectangular slit and a laser source. The laser beam is sent to the slit producing the well-known diffraction pattern on the screen. This paper proposes a simple modification of the single-slit diffraction experiment to increase student attention about the laser beam and its diffraction. A single slit can be used to measure laser beam width. The beam width measurement is demonstrated by using a 632.8 nm Helium Neon (HeNe) laser. In this experiment, the laser beam is assumed as a Gaussian beam. The beam width is determined by scanning in one direction across the laser beam. The measurement results are shown to achieve satisfactory results when compared with a commercial laser beam profiler. By measuring the laser beam widths, students will qualitatively observe that the laser beam width increases along propagation distance. This experiment can be an additional exercise in a single-slit diffraction experiment.

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Farrokhi, Hamid, Wei Zhou, Hong Yu Zheng, and Zhong Li Li. "Characterization of Silicon Wafer Surface Irradiated with Fiber Laser." Key Engineering Materials 447-448 (September 2010): 715–19. http://dx.doi.org/10.4028/www.scientific.net/kem.447-448.715.

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We studied the feasibility of micromachining of silicon wafer using 200 W fiber laser of 1090 nm in wavelength. Irradiated area was observed and analyzed using scanning electron microscope and surface profiler. It was found that micromachining of silicon could not be carried out efficiently. Careful analyses revealed possible causes for the poor machinability: first, very weak plasma formed during the fiber laser-material interaction, leading to low evaporation or melt ejection; second, formation of large amounts of SiO2 resulted in expansion of volume. It is further demonstrated that the surface oxidation can be made use of for the purpose of surface texturing.

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Katto, Masahito, Ryusuke Matsumoto, Kou Kurosawa, Wataru Sasaki, Yasuo Takigawa, and Masahiro Okuda. "Laser beam profiler in the vacuum ultraviolet spectral range using photostimulable phosphor." Review of Scientific Instruments 64, no. 2 (February 1993): 319–24. http://dx.doi.org/10.1063/1.1144251.

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Zhang, S., X. Duan, C. Zeng, K. Shi, X. Zhang, Q. Bi, and Y. Wang. "Pose Calibration for 2D Laser Profiler Integrated in Five-Axis Machine Tools." IOP Conference Series: Materials Science and Engineering 831 (June 6, 2020): 012022. http://dx.doi.org/10.1088/1757-899x/831/1/012022.

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Vasile, T., V. Damian, D. Coltuc, and M. Petrovici. "Single pixel sensing for THz laser beam profiler based on Hadamard Transform." Optics & Laser Technology 79 (May 2016): 173–78. http://dx.doi.org/10.1016/j.optlastec.2015.12.009.

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Yu, Zhou, and Jun Hu. "Microstructure and Characteristic of Biomedical Titanium Alloy Based on Picosecond Laser Micromachining." Materials Science Forum 939 (November 2018): 104–9. http://dx.doi.org/10.4028/www.scientific.net/msf.939.104.

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Laser micromachining has become a hotspot in recent years due to its high precision, non-contact and adjustable parameter. In this paper, TC4 titanium alloy implant samples were conducted to obtain specific surface textures through picosecond laser. The laser parameters which directly influenced the microstructure and characteristic of surface textures were optimized within the context of laser power, scanning speed and scanning number via response surface methodology. The microstructure was evaluated using scanning electron microscope (SEM) while the feature size of the surface textures was measured through surface 3D profiler. In addition, endothelial cell culture was conducted to investigate the biofunctionalization of samples with specific surface textures. It demonstrated that well-structured textures played an important role in promoting cell adhesion and proliferation for titanium alloy implants.

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Gao, Yongzhuo, Haibo Gao, Kunpeng Bai, Mingyang Li, and Wei Dong. "A Robotic Milling System Based on 3D Point Cloud." Machines 9, no. 12 (December 15, 2021): 355. http://dx.doi.org/10.3390/machines9120355.

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Industrial robots have advantages in the processing of large-scale components in the aerospace industry. Compared to CNC machine tools, robot arms are cheaper and easier to deploy. However, due to the poor consistency of incoming materials, large-scale and lightweight components make it difficult to automate robotic machining. In addition, the stiffness of the tandem structure is quite low. Therefore, the stability of the milling process is always a concern. In this paper, the robotic milling research is carried out for the welding pre-processing technology of large-scale components. In order to realize the automatic production of low-conformity parts, the on-site measurement–planning–processing method is adopted with the laser profiler. On the one hand, the laser profiler hand–eye calibration method is optimized to improve the measurement accuracy. On the other hand, the stiffness of the robot’s processing posture is optimized, combined with the angle of the fixture turntable. Finally, the experiment shows the feasibility of the on-site measurement–planning–processing method and verifies the correctness of the stiffness model.

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Li, Hao Wei, Yong Qing Gong, Wei Wei Zhang, and Ming Jiu Xiahou. "Construction of a Digital Microlithography System Based on Violet Semiconductor Laser." Applied Mechanics and Materials 696 (November 2014): 76–82. http://dx.doi.org/10.4028/www.scientific.net/amm.696.76.

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A digital mask microlithography system is designed and constructed, which employs a 405nm semiconductor laser diode as light source, and uses a DMD (Digital Micro-mirror Device) as high-precision digital mask. The microstructure array with logo and optical grating has been obtained successfully on this system. Lithography results have been evaluated carefully with the aid of microscope and white light scanning profiler. The feasibility of the microlithography system has been further proved.

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Hou, Zhan Feng, Zhi Chen, Lin Li, Jing Yu Han, and Zhi Xiong Lu. "Fractal Analysis of Soil Profile Roughness." Advanced Materials Research 383-390 (November 2011): 4944–48. http://dx.doi.org/10.4028/www.scientific.net/amr.383-390.4944.

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In this paper, we address the issue of soil roughness characterisation in the case of agricultural fields having different tillage (roughness) states, that is ploughed, harrowed and rolled surface. By using a laser profiler, the surface height variation trace of three types of tillage soil profiles are obtained. Using this dataset the range of RMS height, autocorrelation length and the fractal characteristic values associated with each agricultural roughness state is estimated, The result show that fractal dimension turned out to be a suitable index for distinguish the different tillage states. But there is no one-to-one correspondence relationship. A soil roughness index was found to be appropriate for the quantification of soil surface roughness.

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Lam, Norris, Jason W. Kean, and Steve W. Lyon. "Modeling streamflow from coupled airborne laser scanning and acoustic Doppler current profiler data." Hydrology Research 48, no. 4 (August 8, 2016): 981–96. http://dx.doi.org/10.2166/nh.2016.257.

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The rating curve enables the translation of water depth into stream discharge through a reference cross-section. This study investigates coupling national scale airborne laser scanning (ALS) and acoustic Doppler current profiler (ADCP) bathymetric survey data for generating stream rating curves. A digital terrain model was defined from these data and applied in a physically based 1-D hydraulic model to generate rating curves for a regularly monitored location in northern Sweden. Analysis of the ALS data showed that overestimation of the streambank elevation could be adjusted with a root mean square error (RMSE) block adjustment using a higher accuracy manual topographic survey. The results of our study demonstrate that the rating curve generated from the vertically corrected ALS data combined with ADCP data had lower errors (RMSE = 0.79 m3/s) than the empirical rating curve (RMSE = 1.13 m3/s) when compared to streamflow measurements. We consider these findings encouraging as hydrometric agencies can potentially leverage national-scale ALS and ADCP instrumentation to reduce the cost and effort required for maintaining and establishing rating curves at gauging station sites similar to the Röån River.

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UMEHARA, Yoshimasa, Shigenori TANAKA, Kenji NAKAMURA, and Yoshinori TSUKADA. "RESEARCH CONCERNING TECHNOLOGY FOR DETECTING OBJECTS OF RIVER SPACE USING LASER PROFILER DATA." Journal of Japan Society of Civil Engineers, Ser. F3 (Civil Engineering Informatics) 73, no. 2 (2017): I_433—I_442. http://dx.doi.org/10.2208/jscejcei.73.i_433.

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Chotiros, Nicholas P., Marcia J. Isakson, Oscar E. Siliceo, and Paul M. Abkowitz. "Roughness measurement by laser profiler and acoustic scattering strength of a sandy bottom." Journal of the Acoustical Society of America 136, no. 4 (October 2014): 2268. http://dx.doi.org/10.1121/1.4900194.

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Aiga, Takehide, Shigeaki Tauchi, and Katsumi Ando. "Characterization of Anti-corrosive Coating Surface Measured by 3 dimensional Laser Topographic Profiler." Zairyo-to-Kankyo 54, no. 3 (2005): 113–19. http://dx.doi.org/10.3323/jcorr1991.54.113.

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Irick, Steven C. "Improved measurement accuracy in a long trace profiler: Compensation for laser pointing instability." Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 347, no. 1-3 (August 1994): 226–30. http://dx.doi.org/10.1016/0168-9002(94)91882-1.

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Al-Shibaany, Zeyad Yousif Abdoon, Pavel Penchev, John Hedley, and Stefan Dimov. "Laser Micromachining of Lithium Niobate-Based Resonant Sensors towards Medical Devices Applications." Sensors 20, no. 8 (April 14, 2020): 2206. http://dx.doi.org/10.3390/s20082206.

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This paper presents a micromachining process for lithium niobate (LiNbO3) material for the rapid prototyping of a resonant sensor design for medical devices applications. Laser micromachining was used to fabricate samples of lithium niobate material. A qualitative visual check of the surface was performed using scanning electron microscopy. The surface roughness was quantitatively investigated using an optical surface profiler. A surface roughness of 0.526 μm was achieved by laser micromachining. The performance of the laser-micromachined sensor has been examined in different working environments and different modes of operation. The sensor exhibits a Quality-factor (Q-factor) of 646 in a vacuum; and a Q-factor of 222 in air. The good match between the modelling and experimental results shows that the laser-micromachined sensor has a high potential to be used as a resonance biosensor.

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Gaffard, C., J. Nash, E. Walker, T. J. Hewison, J. Jones, and E. G. Norton. "High time resolution boundary layer description using combined remote sensing instruments." Annales Geophysicae 26, no. 9 (September 5, 2008): 2597–612. http://dx.doi.org/10.5194/angeo-26-2597-2008.

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Abstract. Ground based remote sensing systems for future observation operations will allow continuous monitoring of the lower troposphere at temporal resolutions much better than every 30 min. Observations which may be considered spurious from an individual instrument can be validated or eliminated when considered in conjunction with measurements from other instruments observing at the same location. Thus, improved quality control of atmospheric profiles from microwave radiometers and wind profilers should be sought by considering the measurements from different systems together rather than individually. In future test bed deployments for future operational observing systems, this should be aided by observations from laser ceilometers and cloud radars. Observations of changes in atmospheric profiles at high temporal resolution in the lower troposphere are presented from a 12 channel microwave radiometer and 1290 MHz UHF wind profiler deployed in southern England during the CSIP field experiment in July/August 2005. The observations chosen were from days when thunderstorms occurred in southern England. Rapid changes near the surface in dry layers are considered, both when rain/hail may be falling from above and where the dry air is associated with cold pools behind organised thunderstorms. Also, short term variations in atmospheric profiles and vertical stability are presented on a day with occasional low cloud, when thunderstorms triggered 50 km down wind of the observing site Improved quality control of the individual remote sensing systems need to be implemented, examining the basic quality of the underlying observations as well as the final outputs, and so for instance eliminating ground clutter as far as possible from the basic Doppler spectra measurements of the wind profiler. In this study, this was performed manually. The potential of incorporating these types of instruments in future upper air observational networks leads to the challenge to improve the observing systems and also to exploit measurements at high temporal resolution in numerical weather prediction. These examples are intended to inform potential operational users of the changes in atmospheric structure that can be observed with the new types of observing system.

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Journal articles on the topic 'Laser Profiler'

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