Journal articles: 'Fiber optic instrument'

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Merrill, Raymond. "Fiber optic musical instrument digital interface." Journal of the Acoustical Society of America 89, no. 5 (May 1991): 2485. http://dx.doi.org/10.1121/1.400862.

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Su, Liang Yu. "LabVIEW Applications for Fiber-Optic Remote Test and Fiber Sensor Systems." Applied Mechanics and Materials 610 (August 2014): 216–20. http://dx.doi.org/10.4028/www.scientific.net/amm.610.216.

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This paper demonstrates applications of LabVIEW in automatic test measurement of fiber optic system.First,the LabVIEW applications in fiber optic system and the basics of instrument connectivity are presented.Then,the aspects of hardware communication to external instruments through GPIB and serial interfaces are analyzed.Next,self-calibrating automated characterization system for depressed cladding applications is demonstrated utilizing the LabVIEW’s GPIB interface. Results of the manual and automatic measurements and the analysis of the measurement trace obtained from the optical time domain reflectometer (OTDR) are shown.In the end,two applications of LabVIEW in fiber optic sensor system are discussed.

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Phillips, Brennan T., Nicholas Chaloux, Russell Shomberg, Adriana Muñoz-Soto, and Jim Owens. "The Fiber Optic Reel System: A Compact Deployment Solution for Tethered Live-Telemetry Deep-Sea Robots and Sensors." Sensors 21, no. 7 (April 4, 2021): 2526. http://dx.doi.org/10.3390/s21072526.

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Tethered deep-sea robots and instrument platforms, such as Remotely Operated Vehicles (ROVs) and vertical-profiling or towed instrument arrays, commonly rely on fiber optics for real-time data transmission. Fiber optic tethers used for these applications are either heavily reinforced load-bearing cables used to support lifting and pulling, or bare optical fibers used in non-load bearing applications. Load-bearing tethers directly scale operations for deep-sea robots as the cable diameter, mass, and length typically require heavy winches and large surface support vessels to operate, and also guide the design of the deep-sea robot itself. In an effort to dramatically reduce the physical scale and operational overhead of tethered live-telemetry deep-sea robots and sensors, we have developed the Fiber Optic Reel System (FOReelS). FOReelS utilizes a customized electric fishing reel outfitted with a proprietary hollow-core braided fiber optic fishing line and mechanical termination assembly (FOFL), which offers an extremely small diameter (750 μm) load-bearing (90 lb/400 N breaking strength) tether to support live high-bandwidth data transmission as well as fiber optic sensing applications. The system incorporates a novel epoxy potted data payload system (DPS) that includes high-definition video, integrated lighting, rechargeable battery power, and gigabit ethernet fiber optic telemetry. In this paper we present the complete FOReelS design and field demonstrations to depths exceeding 780 m using small coastal support vessels of opportunity. FOReelS is likely the smallest form factor live-telemetry deep-sea exploration tool currently in existence, with a broad range of future applications envisioned for oceanographic sensing and communication.

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Andreev, A., G. Diankov, B. Zafirova, and A. Kebedjiev. "Wavelength-demultiplexed fiber-optic temperature-measurement instrument." Sensors and Actuators A: Physical 30, no. 3 (February 1992): 215–18. http://dx.doi.org/10.1016/0924-4247(92)80123-k.

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Sum, Stephen T., and Steven D. Brown. "Standardization of Fiber-Optic Probes for Near-Infrared Multivariate Calibrations." Applied Spectroscopy 52, no. 6 (June 1998): 869–77. http://dx.doi.org/10.1366/0003702981944418.

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The standardization of Fourier transform near-infrared (FT-NIR) spectrometers equipped with fiber-optic probes was investigated. FT-NIR spectra of caustic brines for an industrial process were measured on two different instruments. Calibration transfer across the instruments and probes was studied by employing calibration models built on one instrument to predict properties from spectra measured on the other. The transfer was examined by using spectra without and with preprocessing. The preprocessing methods included a Savitzky–Golay (SG) derivative polynomial filter, a procedure based on a finite impulse response (FIR) filter, and a combination of both. In addition to being a preprocessing technique, the FIR filter is also a standardization method that transforms the instrument response function of one instrument to match that of another. The transformation is performed over a moving processing window without the use of transfer standards. In this study, application of the FIR filter to first-derivative spectra provided the best multivariate calibration models and led to the successful transfer of calibration across different probes and spectrometers.

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Bright, Frank V. "A New Fiber-Optic-Based Multifrequency Phase-Modulation Fluorometer." Applied Spectroscopy 42, no. 8 (November 1988): 1531–37. http://dx.doi.org/10.1366/0003702884429580.

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A new fiber-optic-based fluorescence lifetime instrument is described which is useful for the study of complex fluorescence decay kinetics. The new instrument consists of a multifrequency phase fluorometer coupled to a fiber-optic probe. To demonstrate the power of the new instrument, we show results for the unequivocal resolution of single, double, and triple exponential decays of fluorescence. In addition, spectral coverage in the ultraviolet and visible regions is possible, and lifetimes from approximately 200 ns to 150 ps are easily determined for samples as dilute as 0.1 μM.

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Victor, Mark A., and Stanley R. Crouch. "Absorbance-Corrected Synchronous Fluorescence with a Fiber-Optic-Based Fluorometer." Applied Spectroscopy 49, no. 7 (July 1995): 1041–47. http://dx.doi.org/10.1366/0003702953964778.

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Synchronous fluorescence spectroscopy is frequently used to resolve multiple components in mixtures without separation. However, uncompensated inner-filter effects can lead to unexpected and/or large quantitative errors. An instrument and a method that correct for primary and secondary inner-filter effects in synchronous fluorescence spectroscopy have been designed and characterized. A bifurcated fiber-optic-based diode array fluorometer that simultaneously measures front-surface fluorescence and absorbance was constructed. A transfer function that mathematically describes the coupling efficiency between the excitation and emission legs of the fiber optics is defined and characterized. Once characterized, such a fluorometer is capable of calculating what the fluorescence measurement would be in the absence of inner-filter effects. Several experimental procedures for determining the instrument's transfer function are compared and discussed. Applications of the various procedures to experimental fluorescence inner-filter corrections to problematic samples are demonstrated.

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Garrido-Varo, Ana, Ana Sánchez-Bonilla, Francisco Maroto-Molina, Cecilia Riccioli, and Dolores Pérez-Marín. "Long-Length Fiber Optic Near-Infrared (NIR) Spectroscopy Probes for On-Line Quality Control of Processed Land Animal Proteins." Applied Spectroscopy 72, no. 8 (June 13, 2018): 1170–82. http://dx.doi.org/10.1177/0003702817752111.

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This research was conducted using a spectral database comprising 346 samples of processed animal proteins (PAPs) with a range of compositions, analyzed using a Fourier transform near-infrared spectroscopy multichannel instrument (Matrix-F, Bruker Optics) coupled to a 100 m fiber optic cable. Using both its static and dynamic operating modes (on a conveyor belt), simulating the movement of the product in the plant, the predictive capabilities of both modes of analysis were assessed and compared, for the purposes of predicting moisture, protein, and ashes. The results show that both exhibit highly similar degrees of precision and accuracy for predicting these parameters. This research provides a foundation of scientific-technical knowledge, hitherto unknown, regarding the “on-line” incorporation of an instrument (equipped with a 100 m fiber optic cable) into a processing plant of by-products of animal origin.

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Noyes, R. W., T. M. Brown, S. Horner, S. Korzennik, and P. Nisenson. "The AFOE—A New Instrument for Asteroseismology." International Astronomical Union Colloquium 137 (1993): 752–54. http://dx.doi.org/10.1017/s0252921100018807.

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AbstractWe describe technical aspects and performance characteristics of an Advanced Fiber Optic Spectrograph (AFOE), planned for the Mt. Hopkins 1.5 m telescope for asteroseismology of sun-like stars.

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Hausner, Mark B., and Scott Kobs. "Identifying and Correcting Step Losses in Single-Ended Fiber-Optic Distributed Temperature Sensing Data." Journal of Sensors 2016 (2016): 1–10. http://dx.doi.org/10.1155/2016/7073619.

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Fiber-optic distributed temperature sensing (DTS) makes it possible to observe temperatures on spatial scales as fine as centimeters and at frequencies up to 1 Hz. Over the past decade, fiber-optic DTS instruments have increasingly been employed to monitor environmental temperatures, from oceans to atmospheric monitoring. Because of the nature of environmental deployments, optical fibers deployed for research purposes often encounter step losses in the Raman spectra signal. Whether these phenomena occur due to cable damage or impingements, sharp bends in the deployed cable, or connections and splices, the step losses are usually not adequately addressed by the calibration routines provided by instrument manufacturers and can be overlooked in postprocessing calibration routines as well. Here we provide a method to identify and correct for the effects of step losses in raw Raman spectra data. The utility of the correction is demonstrated with case studies, including synthetic and laboratory data sets.

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Hidayati, Miskhatul, and Harmadi Harmadi. "Rancang Bangun Sensor Serat Optik dengan Cladding Zinc Oxide untuk Mendeteksi Kelembaban Udara." Jurnal Fisika Unand 10, no. 2 (April 6, 2021): 255–61. http://dx.doi.org/10.25077/jfu.10.2.255-261.2021.

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Telah dilakukan rancang bangun sensor serat optik dengan cladding zinc oxide untuk mendeteksi kelembaban udara. Sistem sensor serat optik dilakukan dengan metode pengupasan cladding yang diganti dengan Zinc Oxide (ZnO) dengan variasi pengupasan 1 cm, 2 cm, 3 cm, 4 cm, dan 5 cm. Sistem sensor terdiri dari dioda laser sebagai sumber cahaya, serat optik cladding ZnO sebagai pengindra kelembaban, dan sensor OPT101 sebagai fotodetektor, mikrokontroler sebagai pengolah sinyal serta nilai kelembaban udara ditampilkan melalui PC (personal computer). Kelembaban diukur berdasarkan perubahan tegangan keluaran, semakin tinggi kelembaban udara maka semakin tinggi tegangan keluaran sensor. Hasil karakterisasi sensor menunjukkan serat optik dengan panjang pengupasan 2 cm adalah yang paling optimum dalam mengindra kelembaban. Nilai sensitifitas sensor yang dirancang adalah 0,0313 V/%RH dengan koefisien determinasi R2 = 0,9684. Sensor serat optik dengan cladding ZnO mampu mendeteksi kelembaban udara dalam rentang 88% RH s/d 99% RH dengan persentase rata-rata error pada alat ukur yang dirancang adalah 0,75% dibandingkan dengan alat ukur higrometer. A fiber optic sensor design with zinc oxide cladding has been designed to detect air humidity. The fiber optic sensor system was carried out by using the cladding stripping method which was replaced with Zinc Oxide (ZnO) with a stripping variation of 1 cm, 2 cm, 3 cm, 4 cm, and 5 cm. The sensor system consists of a laser diode as a light source, a fiber optic cladding ZnO as a moisture sensor, and an OPT101 sensor as a photodetector, a microcontroller as a signal processor and air humidity values and displayed via a PC (personal computer). Humidity is measured based on changes in the output voltage, the higher the humidity of the air, the higher the sensor output voltage. The results of sensor characterization showed that the optical fiber with a stripping length of 2 cm was the most optimum for sensing moisture. The designed sensor sensitivity value is 0.0313 V/%RH with a coefficient of determination R2 = 0.9684. The fiber optic sensor with ZnO cladding is able to detect air humidity in the range of 88% to 99% with an average error percentage of the designed measuring instrument is 0.75% compared to a hygrometer measuring instrument

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Pustelny, Tadeusz Piotr. "Electroluminescent optical fiber sensor for detection of a high intensity electric field." Photonics Letters of Poland 12, no. 1 (March 31, 2020): 19. http://dx.doi.org/10.4302/plp.v12i1.980.

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On-line testing of high power electromagnetic devices is one of the most important problems of modern industrial metrology. In the paper, the results of experimental investigations of the electric field optical fiber sensor based on the electroluminescent phenomena are presented. The electro¬luminescent effect is observed in some composite semicon¬ductors, among others in zinc sulfide ZnS crystals. In our investigations, the used ZnS crystal was doped with copper Cu atoms as activators. The concentration of activator in the ZnS crystal was about 5.10-4 [g/g]. According to plans of investi¬gations of the elaborated electroluminescent sensor, the spectral properties as well as the intensity of light emission in sinusoidal alternating electric field were tested.Full Text: PDF References:K.T.V. Grattan, Fiber Optic Fluorescence Thermometry, Chapman and Hall, London, 1996 [CrossRef]K. Kyuma, S. Tai, T. Sawada, "Fiber-optic instrument for temperature measurement", J. Quntum. Electronics, 73(3), 1997 [CrossRef]A. Brief, J. Chem. Educ., 88(6), 731 (2011). [CrossRef]T. Pustelny, B. Pustelny, "Investigation of electroluminophores for their practical application in optical fibre sensor technology", Opto-Electronics Rev.,10(3), 193 (2002). [CrossRef]A.Wrzesinska, Photo- and electroluminophore, Wroclaw, PWN Press, 1988, (in polish) [DirectLink]K.A. Franz, W.G. Kehr, "Luminescent Materials", Ullmans Encyclopedie of Industral Chemistry, Wiley-VCH, Veinhen, 2008 [CrossRef]A.G. Milnes, Deep Impurities In Semiconductors, A Willey-Interscience Publication, Toronto, 1993 [DirectLink]M. Aven, J.S. Prener, Physics and Chemistry of II-VI Compounds, North-Holland Publishing Company - Amsterdam, 1993 [DirectLink]P.K. Cheo, Fiber Optics Devices and Systems, Prentice-Hall, 1985 [CrossRef]D. Randall, Fluorescence and Phosphorescence, Grown, Oxford, 2007. [CrossRef]M. Koen, Photoconductivity of Semiconductors, Edited by Parks, New York, 1996 [CrossRef]K.R. Murphy, C.A. Stedmon, Annal. Methods, 6(3), 658, (2014) [CrossRef]T. Pustelny, K. Barczak, K. Gut, J. Wojcik, "Special optical fiber type D applied in optical sensor of electric currents", Optica Applicata, 34(4), 531 (2004). [DirectLink]K. Barczak, T. Pustelny, D. Dorosz, J. Dorosz, "Polarization maintaining fibers for application in magnetic field measurements", Europ. Phys. Journal: S.T., 154, 11, (2008) [CrossRef]

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Titov, A. A., and A. Yu Albagachiev. "Fiber-Optic Instrument for Measuring the Deflection of Components." Measurement Techniques 57, no. 10 (January 2015): 1128–30. http://dx.doi.org/10.1007/s11018-015-0590-9.

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Heo, Jin Seok, Jung Ju Lee, and Jeong Ok Lim. "A Micro Total Reflective Extrinsic Fabry-Parot Interferometric Fiber Optic Pressure Sensor for Medical Application." International Journal of Modern Physics B 17, no. 08n09 (April 10, 2003): 1199–204. http://dx.doi.org/10.1142/s0217979203018740.

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This paper presents the newly designed fiber optic pressure sensor using the TR-EFPI fiber optic sensor with a single mode fiber (SMF), and a micro fabricated diaphragm. The output signal of TR-EFPI fiber optic pressure sensor can be easily analyzed based on the spliced loss based model and large deflection theory. Then, we can design the optimal length between the thin film of diaphragm and the end of single mode fiber. From these analyses, the relation between the applied pressure and the output signal of TR-EFPI fiber optic sensor can be simulated. Based on these processes, we can design the TR-EFPI fiber optic pressure sensor measuring various conditions by changing the size of thin film. As the newly designed TR-EFPI fiber optic pressure sensor can be fabricated in small size and has good sensitivity, it can be applied to medical instrument like pressure sensor and force sensor for catheter and minimally invasive surgery robot for safer surgery.

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Schimleck, L. R., J. L. M. Matos, R. Trianoski, and J. G. Prata. "Comparison of Methods for Estimating Mechanical Properties of Wood by NIR Spectroscopy." Journal of Spectroscopy 2018 (2018): 1–10. http://dx.doi.org/10.1155/2018/4823285.

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Near-infrared (NIR) spectroscopy provides a rapid alternative to traditional methods of wood property assessment. For organizations who assess wood properties on a large scale, multisite, multispecies calibrations are of practical interest. We examined NIR spectroscopy for the estimation of density (at 12% moisture content), modulus of elasticity (MOE), and modulus of rupture (MOR) using clear wood samples obtained from several pine species (Pinus caribaeavar. bahamensis, var.hondurensis, and var. caribaea, P.chiapensis,P.maximinoi,P.oocarpa,P.taeda, andP.tecunumanii). We compared different methodologies for collecting spectra, that is, benchtop instrument versus benchtop fiber-optic probe and field portable fiber-optic probe, and different wood surfaces (radial and transverse). Calibrations based on the benchtop instrument were superior to those obtained using the fiber-optic probe systems. Difficulty with adequately representing the sample when collecting spectra using a fiber-optic probe and lower quality spectra explain the differences among the data sets. Spectra collected from radial and transverse surfaces provided similar calibration statistics. The calibrations obtained for density (R2 = 0.81, SECV = 38.5 kg/m3) and MOE (R2 = 0.81, SECV = 1124 GPa) using benchtop instrument spectra demonstrate that it is possible to obtain general calibrations for estimating the wood properties of a number of tropical, subtropical, and temperate pine species.

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Fong, Andrew, and Gary M. Hieftje. "Low-Volume Diffuse-Transmittance Fiber-Optic Near-IR Spectrophotometer." Applied Spectroscopy 49, no. 4 (April 1995): 486–92. http://dx.doi.org/10.1366/0003702953964309.

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A simple, inexpensive near-IR spectrophotometer is described that employs single fiber-optic strands in a diffuse-transmission geometry. The instrument can examine unusually small sample volumes and offers sufficient throughput to perform multicomponent analyses on diffusely transmitting powdered samples. Control of the effective optical pathlength is found to be critical in obtaining reproducible results when scattering samples are to be analyzed. A pseudo-double-beam arrangement is employed to reduce instrument noise and to set the optical pathlength independently for each sample. Sample sizes of only a few tens of milligrams are required for analysis. The resulting performance is nearly equivalent to that of a commercial reflectance instrument. An average standard error of prediction of 2.77% w/w was obtained for four-component mixtures of benzoic acid derivatives. The single-fiber transmission geometry is shown to be useful also in the near-IR analysis of microliter volumes of liquids. A standard error of cross-validation of 17 mM sodium chloride dissolved in water was achieved.

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Nisenson, P., A. Contos, S. Korzennik, R. Noyes, and T. Brown. "The Advanced Fiber-optic Echelle (AFOE) and Extrasolar Planet Searches." International Astronomical Union Colloquium 170 (1999): 143–53. http://dx.doi.org/10.1017/s025292110004848x.

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AbstractThe Advanced Fiber-Optic Echelle (AFOE) is a fiber-fed bench-top spectrograph specifically designed for precise radial velocity observations. The AFOE is permanently located at the 1.5-m telescope at Smithsonian’s Whipple Observatory in Arizona and is regularly used for monitoring exo-planet candidate stars and for asteroseismology observations. In this paper, we discuss the status of the instrument, as well as an upgrade to the instrument, a Fabry-Perot reference, which may prove important both for the AFOE and for all precise radial velocity (PRV) facilities.

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Norgia, Michele, and Alessandro Pesatori. "Interferometric Instrument for Thickness Measurement on Blown Films." Photonics 8, no. 7 (June 29, 2021): 245. http://dx.doi.org/10.3390/photonics8070245.

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Real-time measurement of plastic film thickness during production is extremely important to guarantee planarity of the final film. Standard techniques are based on capacitive measurements, in close contact with the film. These techniques require continuous calibration and temperature compensation, while their contact can damage the film. Different optical contactless techniques are described in literature, but none has found application to real production, due to the strong vibration of the films. We propose a new structure of low-coherence fiber interferometer able to measure blown film thickness during productions. The novel fiber-optic setup is a cross between an autocorrelator and a white light interferometer, taking the advantages of both approaches.

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Schrum, Kimberley F., Seung Hyeon Ko, and Dor Ben-Amotz. "Description and Theory of a Fiber-Optic Confocal and Super-Focal Raman Microspectrometer." Applied Spectroscopy 50, no. 9 (September 1996): 1150–55. http://dx.doi.org/10.1366/0003702963905187.

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A fiber-optic bundle, placed in the imaging plane of a microspectrometer, functions as a variable-size pinhole. This arrangement allows for conventional confocal measurements to be made by collecting the signal from the central fiber. On the other hand, measurements arising from a larger focal volume are made by integrating the signal from the entire bundle. This new “super-focal” imaging technique yields larger imaging depth without any loss in spectral resolution. The instrument design and performance are described, as well as geometric optics calculations which accurately predict the depth resolution and oscillations in the super-focal depth response. Raman scattering from a three-component layered sample is used to illustrate the extension of this technique to more complicated systems.

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Golikov, A., V. Pankratov, and M. Barulina. "Prospects for Using Carbon Nanotubes in Precision Instrument Engineering." Materials Science Forum 992 (May 2020): 770–74. http://dx.doi.org/10.4028/www.scientific.net/msf.992.770.

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This research deals with the prospects for application of modern nanomaterials as exemplified by carbon nanotubes for development of new classes of precision measuring instruments or for significant improvement of the performance of existing sensors and systems based on sensors. Carbon nanotubes have been known since the end of the 20th century, but production of high-quality carbon nanotubes on a commercial scale has become possible relatively recently, owing, inter alia, to researches of Russian scientists. Carbon nanotubes have unique properties which hold much promise for their use in different areas of science and technology. Thus, use of nanotubes in precision instrument engineering can solve a number of problems, such as increase in reliability, accuracy, durability, weight and size reduction, etc. Fiber optic gyroscopes based on microstructured optical fiber are considered in this research as an example to demonstrate that use of carbon nanotubes allows significant reduction of the temperature differences in the fiber and that such reduction, in its turn, leads to lower dependence of the FOG characteristics on the temperature effects under actual operating conditions. A mathematical model of the equivalent thermal conductivity of a microstructured fiber loop, all or some channels of which are filled with carbon nanotubes, has been developed in this research. A comparative analysis has been made of the distribution of heat in coils with the considered and traditional fibers under different temperature effects – harmonic, random and stepped.

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Ferentinou, Maria. "Sinkhole collapse propagation studies through instrumented small-scale physical models." Proceedings of the International Association of Hydrological Sciences 382 (April 22, 2020): 71–76. http://dx.doi.org/10.5194/piahs-382-71-2020.

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Abstract. Sinkholes are common geohazards, frequently responsible for sudden catastrophic ground collapse. Thus, effective monitoring would allow for further understanding of the mechanism of occurrence of sinkholes and lead to the development of a potential early warning system to provide an alarm or a warning of incipient col-lapse. In the current study, fiber Bragg gratings (FBGs) were used to instrument reduced scale models, simulating a sinkhole event. The tests were conducted by embedding optic fiber sensors in the soil and inducing failure until critical conditions were reached. FBG sensors were manufactured in a single optic fiber cable. The measurements of small horizontal strains were recorded simultaneously and in various positions. Failure mechanism was found to relate to the backfill density, and compaction.

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Ma, Jiaying, and Dor Ben-Amotz. "Rapid Micro-Raman Imaging Using Fiber-Bundle Image Compression." Applied Spectroscopy 51, no. 12 (December 1997): 1845–48. http://dx.doi.org/10.1366/0003702971939668.

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A new technique for rapid Raman imaging and chemical analysis of micro-composites and biomaterials, with potential applications in real-time robotic vision, automated manufacturing, and medical imaging, is described and demonstrated. The key feature of this new instrument is a fiber-optic bundle used to compress two-dimensional images onto a one-dimensional fiber stack, which serves as the entrance slit of an imaging optical spectrograph. Thus a complete Raman spectrum is simultaneously collected from every point within a sample in a single scan of a charge-coupled-device (CCD) detector. The method is demonstrated by using Raman imaging of a microscopic mixed-salt sample. Its efficiency relative to alternative Raman imaging methods is quantitatively evaluated, and potential applications in other spectral imaging measurements are discussed. Index Headings: Raman spectroscopy; Spectral imaging; Chemical imaging; Fiber optics; Chemical sensor.

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Fauzi, Ahmad. "Perancangan Konfigurasi FTTH Jaringan Akses Fiber Optik Dengan Optisystem Dalam Modul Praktikum Komunikasi Optik." Indonesian Journal of Applied Informatics 5, no. 2 (January 19, 2022): 146. http://dx.doi.org/10.20961/ijai.v5i2.45623.

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AbstrakPenelitian ini bertujuan untuk merancang modul praktikum Sistem Komunikasi Fiber Optik yang ada pada mata kuliah Jaringan Pita Lebar dan Komunikasi Optik. Penelitian ini dilakukan dengan metode perancangan dan eksperimen, yaitu dengan melaksanakan perancangan pada konfigurasi sistem jaringan fisik yang telah ada. Dengan menggunakan modul yang dirancang, pada hasilnya akan dapat dilakukan pengukuran dan perhitungan link budget rancangan tersebut. , instrumen penilaian yang digunakan dalam aktivitas pembelajaran harus dapat menilai kinerja mahasiswa berdasarkan kriteria kompetensi teknis dan supervisi yang diharapkan [1]. Perancangan jaringan Fiber To The Home (FTTH) yang dilakukan dibuat dalam perangkat lunak simulasi jaringan fiber optik, yaitu Optisystem. Sebagaimana kegiatan fisiknya, pengukuran dirancang menggunakan optical power meter, Optical Time Domain Reflectometer (OTDR) dan BER analyzer [2]. Hasil penelitiannya, dapat disusun sebuah konfigurasi FTTH yang dimuat pada modul praktikum Sistem Komunikasi Fiber Optik yang tepat berikut buku panduan praktikumnya (jobsheet) dengan nilai daya pada jaringan sebesar – 16,420 dBm, yakni memenuhi standar yang diperbolehkan.===========AbstractThis study aims to design a Fiber Optic Communication System practicum module in the Broadband Network and Optical Communication course. This research was conducted by design and experimental methods, namely by implementing the design on the existing physical network system configuration. By using the designed module, the results will be able to measure and calculate the design link budget. , the assessment instrument used in learning activities must be able to assess student performance based on the expected criteria of technical competence and supervision[1]. The Fiber To The Home (FTTH) network design is made in optical fiber network simulation software, namely Optisystem. As with its physical activities, measurements are designed using an optical power meter, Optical Time Domain Reflectometer (OTDR) and a spectrum analyzer[2]. The results of the research, a FTTH configuration can be compiled which is loaded on the correct Fiber Optic Communication System practicum module along with the practical manual (jobsheet) with a power value on the network of - 16,420 dBm, which meets the allowed standards.

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Battey, David E., Joseph B. Slater, Ronald Wludyka, Harry Owen, David M. Pallister, and Michael D. Morris. "Axial Transmissive f/1.8 Imaging Raman Spectrograph with Volume-Phase Holographic Filter and Grating." Applied Spectroscopy 47, no. 11 (November 1993): 1913–19. http://dx.doi.org/10.1366/0003702934066082.

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An axial transmissive Raman spectrograph is described. The instrument employs volume-phase holograms as the laser line rejection filter and transmission grating. The on-axis configuration and the use of a high-spatial-frequency transmission grating allows nearly diffraction-limited imaging and pixel-limited resolution at f/1.8. The performance of the instrument is demonstrated for fiber-optic probe and microprobe Raman spectroscopy.

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Tosi, Daniele, Edoardo Gino Macchi, and Alfredo Cigada. "Fiber-Optic Temperature and Pressure Sensors Applied to Radiofrequency Thermal Ablation in Liver Phantom: Methodology and Experimental Measurements." Journal of Sensors 2015 (2015): 1–22. http://dx.doi.org/10.1155/2015/909012.

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Radiofrequency thermal ablation (RFA) is a procedure aimed at interventional cancer care and is applied to the treatment of small- and midsize tumors in lung, kidney, liver, and other tissues. RFA generates a selective high-temperature field in the tissue; temperature values and their persistency are directly related to the mortality rate of tumor cells. Temperature measurement in up to 3–5 points, using electrical thermocouples, belongs to the present clinical practice of RFA and is the foundation of a physical model of the ablation process. Fiber-optic sensors allow extending the detection of biophysical parameters to a vast plurality of sensing points, using miniature and noninvasive technologies that do not alter the RFA pattern. This work addresses the methodology for optical measurement of temperature distribution and pressure using four different fiber-optic technologies: fiber Bragg gratings (FBGs), linearly chirped FBGs (LCFBGs), Rayleigh scattering-based distributed temperature system (DTS), and extrinsic Fabry-Perot interferometry (EFPI). For each instrument, methodology forex vivosensing, as well as experimental results, is reported, leading to the application of fiber-optic technologiesin vivo. The possibility of using a fiber-optic sensor network, in conjunction with a suitable ablation device, can enable smart ablation procedure whereas ablation parameters are dynamically changed.

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Kilpatrick, James M., and Vladimir B. Markov. "Full-Field Laser Vibrometer for Instantaneous Vibration Measurement and Non-Destructive Inspection." Key Engineering Materials 437 (May 2010): 407–11. http://dx.doi.org/10.4028/www.scientific.net/kem.437.407.

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We describe a system for real-time, full-field vibrometry, incorporating features of high-speed electronic speckle pattern interferometry (ESPI) and laser Doppler velocimetry (LDV). Based on a 2D interferometric sensor array, comprising 16×16 parallel illumination and detection channels, the matrix laser vibrometer (MLV), captures full-field data instantaneously, without beam scanning. The instrument design draws on the advantages of scale offered by modern telecommunications fiber optic and digital electronics. The resulting architecture, comprising a compact measurement probe linked by fiber optic umbilical to a remote electronics unit, facilitates practical application to the full-field study of transient vibrations and rapid non-destructive inspection of composite materials.

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Carroll, Mary K., and Gary M. Hieftje. "A Novel Fiber-Optic-Based Pump-Probe Instrument for the Acquisition of Kinetic Information." Applied Spectroscopy 46, no. 2 (February 1992): 317–21. http://dx.doi.org/10.1366/0003702924125465.

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A pump-probe instrument is described that utilizes two beams from the same laser and a fiber-optic-based sample cell for low-temperature measurements. The utility of this instrument is demonstrated through an examination of the excited-state kinetics of 2,7-diphenylphenanthrene, for which the rate constant of singlet-to-triplet intersystem crossing is found to be approximately 8 × 105 s−1. This molecule is interesting in that it undergoes an unusual rotational conformation change in the triplet state with a rate constant of 2.4 × 108 s−1 at 77 K.

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Riza, Nabeel A., and Farzan N. Ghauri. "Super-resolution variable fiber optic attenuator instrument using digital micromirror device (DMD™)." Review of Scientific Instruments 76, no. 9 (September 2005): 095102. http://dx.doi.org/10.1063/1.2038587.

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Zhao, Jianhua, Harvey Lui, David I. McLean, and Haishan Zeng. "Toward instrument-independent quantitative measurement of fluorescence intensity in fiber-optic spectrometer systems." Applied Optics 46, no. 29 (October 4, 2007): 7132. http://dx.doi.org/10.1364/ao.46.007132.

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BELTRAME, GIORGIO, and PATRIZIA BUSATTO. "DOUBLE USE OF OPTIC FIBER DURING VITRECTOMY AS A TRANSILLUMINATOR AND INDENTER INSTRUMENT." Retina 26, no. 2 (February 2006): 223–24. http://dx.doi.org/10.1097/00006982-200602000-00018.

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Mikhailov, Petr, Zhomart Ualiyev, Assem Kabdoldina, Nurzhigit Smailov, Askar Khikmetov, and Feruza Malikova. "Multifunctional fiber-optic sensors for space infrastructure." Eastern-European Journal of Enterprise Technologies 5, no. 5 (113) (October 31, 2021): 80–89. http://dx.doi.org/10.15587/1729-4061.2021.242995.

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Sensors used in rocket and space technology are subject to extreme external influences in terms of temperature, vibration, and shock. Therefore, the choice of the type of sensors is justified precisely by the resistance to such factors, as well as the ability to ensure the temporal and parametric stability of measurements. A new type of sensors – fiber-optic ones – meets these conditions. The basis for the selection and further improvement of such sensors were such requirements as minimum power consumption, high accuracy and stability of measurements, the ability to combine several measurements in one sensor. It is noted that for space infrastructure the factor of the possibility of simultaneous measurement of several parameters with one sensor is one of the important quality indicators. This is due to the possibility of reducing the number of sensors themselves, which reduces the mass and size parameters of space technology. This applies, first of all, to measurements of pressure and temperature, since they, in aggregate, account for at least 40 % of all measurements in space products. The path of choos-ing the types of methods and sensor designs led to the combination of the amplitude conversion method and optical communication in one sensor. In this case, amplitude modulation of pressure and temperature is carried out by a microelec-tromechanical unit (module), and the modulated optical signal is transmitted by an optical module. Such a modular composition of the sensor makes it possible to dispense with optical ana-lyzers (interrogators) and carry out further pro-cessing based on standard interfaces. A limitation of the proposed methods and designs is the need for microelectromechanical structures that measure certain physical quantities. Such structures for fiber-optic sensors are not mass-produced; therefore, their manufacture can be established at instrument-making enterprises with microelectronic equipment

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Chen, Chi-Shi, Chris W. Brown, and Su-Chin Lo. "Calibration Transfer from Sample Cell to Fiber-Optic Probe." Applied Spectroscopy 51, no. 5 (May 1997): 744–48. http://dx.doi.org/10.1366/0003702971940927.

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A calibration transfer method, piecewise direct standardization (PDS), was applied to a set of two-component samples measured on the same UV-visible spectrometer with the use of a cuvette cell with a 10-mm pathlength and a fiber-optic probe with a 2-mm pathlength. Piecewise direct standardization proceeds by determining a structured transformation matrix using the spectra of a few samples measured with both devices. This transformation matrix can then be used to transform any spectrum measured on one device to that obtained on another device, thereby making the calibration model transferable between devices. We used the spectra measured in a cuvette as the standard set and transferred the calibration model obtained for these spectra to spectra measured with a 2-mm fiber-optic probe on the same instrument. The total standard error of prediction (SEP) for the fiber-optic probe was 5.84 before the calibration transfer and 1.87 afterwards. Spectra were also processed by taking the Fourier transform prior to the calibration transfer. The 512 data points in each spectrum were compressed to 32 terms, starting with the first term after the dc offset. This processing reduced the background and the noise. As a consequence, in the Fourier domain, the total SEP was 5.69 before the calibration standardization and 0.79 after the calibration standardization. A calibration transfer was also performed between two fiber-optic probes; the total SEP in the spectral domain was 2.16 prior to the transfer and 1.04 after the transfer, whereas in the Fourier domain the SEP was 1.50 prior to the transfer and 0.77 after the transfer.

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Nishiguchi, Masaru, Morio Ishihara, Itsuo Katakuse, and Michisato Toyoda. "Ion Optical Evaluation of a Miniature Double-Focusing Mass Spectrograph." European Journal of Mass Spectrometry 14, no. 1 (February 2008): 7–15. http://dx.doi.org/10.1255/ejms.907.

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A new miniature double-focusing mass spectrograph has been designed and constructed. The ion optical system was designed based on Mattauch–Herzog geometry. The mass spectrograph employs a focal plane detector consisting of a microchannel plate, a phosphor layer, a fiber-optic plate and a charge-coupled device. For the evaluation of the ion optics of the instrument, the energy and angular focal planes were investigated both experimentally and by simulation. Double focusing was satisfactorily achieved along a straight line over a wide mass range, and the experimental and simulated results were mutually consistent. A second-order element of the transfer matrix was also measured experimentally and proved to be in good agreement with the simulated result.

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Rooth, R. A., and W. Hiemstra. "A Fiber-Optic Tip-Shroud Deflection Measurement System." Journal of Engineering for Gas Turbines and Power 123, no. 2 (October 1, 2000): 359–62. http://dx.doi.org/10.1115/1.1364498.

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A Dutch utility faced the fact that a second stage set of turbine blades of a gas turbine had to be replaced long before the estimated lifetime as a result of tip shroud deflection. This deflection caused the risk of loss of support between the individual tip shroud segments. The goal of this paper is to find the cause of the problem, to see how it increases with time, and to take appropriate action to prevent the problem from occurring again. A fiber-optic tip-shroud deflection monitor has been developed and tested on a gas turbine to study this phenomenon in real time. The optical system is based on astigmatism to derive distance information from the measured optical signals. Characteristic features from the system are the good spatial resolution of about 1 mm, the distance resolution of about 0.1 mm and the distance from the probe tip to the target of about 20 mm. These specifications are difficult to achieve with, for example, capacitive sensors. The probe tip can with stand temperatures of about 500°C. The system can be calibrated in situ, given a stable operation of the gas turbine. This is accomplished by stepping the probe tip over some distance and recording the signals corresponding to a certain point on the tip shroud. The instrument has been used to monitor the tip-shroud deflection in a gas turbine at various loads and over a time span of several months. The results indicate that the deflection can be divided in a part depending on the load and a part that is a permanent deflection. Based on the results, it can be judged whether blades need to be rejected because of a too large deflection.

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Coffey, Charity, Alex Predoehl, and Dwight S. Walker. "Dryer Effluent Monitoring in a Chemical Pilot Plant via Fiber-Optic Near-Infrared Spectroscopy." Applied Spectroscopy 52, no. 5 (May 1998): 717–24. http://dx.doi.org/10.1366/0003702981944139.

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The monitoring of the effluent of a rotary dryer has been developed and implemented. The vapor stream between the dryer and the vacuum is monitored in real time by a process fiber-optic coupled near-infrared (NIR) spectrometer. A partial least-squares (PLS) calibration model was developed on the basis of solvents typically used in a chemical pilot plant and uploaded to an acousto-optic tunable filter NIR (AOTF-NIR). The AOTF-NIR is well suited to process monitoring as it electrically scans a crystal and hence has no moving parts. The AOTF-NIR continuously fits the PLS model to the currently collected spectrum. The returned values can be used to follow the drying process and determine when the material can be unloaded from the dryer. The effluent stream was monitored by placing a gas cell in-line with the vapor stream. The gas cell is fiber-optic coupled to a NIR instrument located 20 m away. The results indicate that the percent vapor in the effluent stream can be monitored in real time and thus be used to determine when the product is free of solvent.

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Xie, Haiyan, Zhiyuan Xie, Monirehalsadat Mousavi, Niels Bendsoe, Mikkel Brydegaard, Johan Axelsson, and Stefan Andersson-Engels. "Design and validation of a fiber optic point probe instrument for therapy guidance and monitoring." Journal of Biomedical Optics 19, no. 7 (March 12, 2014): 071408. http://dx.doi.org/10.1117/1.jbo.19.7.071408.

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POKORNY, JOEL, HANNAH SMITHSON, and JULES QUINLAN. "Photostimulator allowing independent control of rods and the three cone types." Visual Neuroscience 21, no. 3 (May 2004): 263–67. http://dx.doi.org/10.1017/s0952523804213207.

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This report describes a second-generation photostimulator with four primary lights that allows independent control of the stimulation of the four receptor types in the human eye. The new design uses LEDs (with light levels controlled by eight drivers that include voltage-to-frequency converters that provide 1-μs pulses at frequencies up to 250 kHz), with four center channels being combined by use of a fiber optic assembly, and likewise for four surround channels. Four fiber optic bundles are merged into a single bundle whose output is fed into a spatial homogenizer terminated by a diffuser. An interference filter is sandwiched between each LED and the fiber optic bundle. Two camera lenses collimate light from the diffusers, one for center and one for surround. The center-surround field configuration is formed by a photometric cube with a mirrored ellipse on the hypotenuse. A field lens places images of the diffusers in the plane of an artificial pupil. The fields are highly uniform. Following alignment and calibration, the center and surround fields are indistinguishable. An observer calibration procedure, designed to compensate for prereceptoral filtering, is shown by calculation to correct also for normal observer receptoral spectral sensitivity variation. With the instrument calibrated for the individual observer, a peripherally fixated 200-ms 40% contrast rod center field pulse, highly conspicuous under dark adaptation, is invisible following light adaptation.

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Zhang, Xiao Yue, Xiao Jing Yi, and Chun Xi Zhang. "Optical-Mechanical-Electrical Integrative Design of Fiber Optic Gyro/Beidou/Odometer Integrated Navigation System." Applied Mechanics and Materials 644-650 (September 2014): 1346–50. http://dx.doi.org/10.4028/www.scientific.net/amm.644-650.1346.

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To improve the reliability, real-time performance and maintainability of navigation system, an optical-mechanical-electrical integrative design method of the fiber optic gyro inertial navigation /beidou/odometer integrated navigation system is proposed. Based on the basic working principle of the integrated navigation system, design of system structure and signal connection are implemented. In the integrated navigation system, all-fixed-structure, instrument and system integrative design and modularization design are used. At last, the integrated navigation system is developed, north seeking test and vehicle test are carried out to demonstrate the validity of the referred system design.

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Li, Hui, Liyang Cui, Zhili Lin, and Chunxi Zhang. "Analysis and Optimization of Dynamic Measurement Precision of Fiber Optic Gyroscope." Mathematical Problems in Engineering 2013 (2013): 1–9. http://dx.doi.org/10.1155/2013/265895.

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In order to improve the dynamic performance of high precision interferometer fiber optic gyroscope (IFOG), the influencing factors of the fast response characteristics are analyzed based on a proposed assistant design setup, and a high dynamic detection method is proposed to suppress the adverse effects of the key influencing factors. The assistant design platform is built by using the virtual instrument technology for IFOG, which can monitor the closed-loop state variables in real time for analyzing the influence of both the optical components and detection circuit on the dynamic performance of IFOG. The analysis results indicate that nonlinearity of optical Sagnac effect, optical parameter uncertainty, dynamic characteristics of internal modules and time delay of signal detection circuit are the major causes of dynamic performance deterioration, which can induce potential system instability in practical control systems. By taking all these factors into consideration, we design a robust control algorithm to realize the high dynamic closed-loop detection of IFOG. Finally, experiments show that the improved 0.01 deg/h high precision IFOG with the proposed control algorithm can achieve fast tracking and good dynamic measurement precision.

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Lindsey, Nathaniel J., T. Craig Dawe, and Jonathan B. Ajo-Franklin. "Illuminating seafloor faults and ocean dynamics with dark fiber distributed acoustic sensing." Science 366, no. 6469 (November 28, 2019): 1103–7. http://dx.doi.org/10.1126/science.aay5881.

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Distributed fiber-optic sensing technology coupled to existing subsea cables (dark fiber) allows observation of ocean and solid earth phenomena. We used an optical fiber from the cable supporting the Monterey Accelerated Research System during a 4-day maintenance period with a distributed acoustic sensing (DAS) instrument operating onshore, creating a ~10,000-component, 20-kilometer-long seismic array. Recordings of a minor earthquake wavefield identified multiple submarine fault zones. Ambient noise was dominated by shoaling ocean surface waves but also contained observations of in situ secondary microseism generation, post–low-tide bores, storm-induced sediment transport, infragravity waves, and breaking internal waves. DAS amplitudes in the microseism band tracked sea-state dynamics during a storm cycle in the northern Pacific. These observations highlight this method’s potential for marine geophysics.

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Casay, G. A., M. I. Daneshvar, and G. Patonay. "Development of a Fiber Optic Biomolecular Probe Instrument Using Near Infrared Dyes and Semiconductor Laser Diodes." Instrumentation Science & Technology 22, no. 4 (November 1994): 323–41. http://dx.doi.org/10.1080/10739149408001192.

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Yang, Hong Lei, Shi Bin Liang, Xue Peng Miao, Min Cao, and Ming Chang. "Research and Application of Optical Fiber Sensing Technology on High Voltage Transmission Line Monitoring." Applied Mechanics and Materials 462-463 (November 2013): 59–63. http://dx.doi.org/10.4028/www.scientific.net/amm.462-463.59.

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On-line monitoring of high voltage transmission lines can prevent or reduce the accidents of transmission reduced by icing,wave,breeze vibrations of electric wires and the dropping of electrical insulators.An on-line monitoring system of high voltage transmission lines based on optical fiber sensing technology is setted in this paper.Fiber optic signal demodulation instrument in the transformer substation receives the signal sent by the optical fiber Bragg grating sensors fitted on transmission lines and electric power towers,and then the signal was sent to the transmission line monitoring center by the power system network.Field hang net experiments shows that the system can monitor the high voltage transmission lines accurately for a long time.

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Hojat, Azadeh, Maddalena Ferrario, Diego Arosio, Marco Brunero, Vladislav Ivov Ivanov, Laura Longoni, Andrea Madaschi, Monica Papini, Greta Tresoldi, and Luigi Zanzi. "Laboratory Studies Using Electrical Resistivity Tomography and Fiber Optic Techniques to Detect Seepage Zones in River Embankments." Geosciences 11, no. 2 (February 7, 2021): 69. http://dx.doi.org/10.3390/geosciences11020069.

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We present the results of laboratory experiments on a down-scaled river levee constructed with clayey material collected from a river embankment where a permanent resistivity instrument has operated since 2015. To create potential seepages through the levee, two zones (5 × 4 cm and 10 × 2 cm) were filled with sand during the levee construction. Electrical resistivity tomography (ERT) technique and Fiber Bragg Grating (FBG) technology were used to study time-lapse variations due to seepage. The ERT profile was spread on the levee crest and the Wenner array with unit electrode spacing a = 3 cm was used. Six organic modified ceramics (ORMOCER) coated 250 μm-diameter fibers were deployed in different parts of the levee. Time-lapse measurements were performed for both techniques from the beginning of each experiment when water was added to the river side until the water was continuously exiting from the seepage zones. The results showed that ERT images could detect seepages from the early stages. Although with a short delay compared to ERT, fiber optic sensors also showed their ability to detect water infiltrations by measuring temperature changes. Both technologies being successful, a discussion about respective peculiarities and pros and cons is proposed to suggest some criteria in choosing the proper technique according to the specific needs.

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Kraft, Martin, Michael Jakusch, Manfred Karlowatz, Abraham Katzir, and Boris Mizaikoff. "New Frontiers for Mid-Infrared Sensors: Towards Deep Sea Monitoring with a Submarine FT-IR Sensor System." Applied Spectroscopy 57, no. 6 (June 2003): 591–99. http://dx.doi.org/10.1366/000370203322005256.

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A sub-sea deployable fiber-optic sensor system for the continuous determination of a range of environmentally relevant volatile organic compounds in seawater has been developed. The prototype of a robust, miniaturized Fourier transform infrared (FT-IR) spectrometer for in situ underwater pollution monitoring was designed, developed, and built in our research group. The assembled instrument is enclosed in a sealed aluminium pressure vessel and is capable of maintenance-free operation in an oceanic environment down to depths of at least 300 m. The whole system can be incorporated either in a tow frame or a remotely operated vehicle (ROV). A suitable fiber-optic sensor head was developed, optimized in terms of sensitivity and hydrodynamics, and connected to the underwater FT-IR spectrometer. Due to a modular system design, various other sensor head configurations could be realized and tested, ensuring facile adaptation of the instrument to future tasks. The sensor system was characterized in a series of laboratory and simulated field tests. The sensor proved to be capable of quantitatively detecting a range of chlorinated hydrocarbons and monocyclic aromatic hydrocarbons in seawater down to the low ppb (μg/L) concentration range, including mixtures of up to 6 components. It has been demonstrated that varying amounts of salinity, turbidity, or humic acids, as well as interfering seawater pollutants, such as aliphatic hydrocarbons or phenols, do not significantly influence the sensor characteristics. In addition, the sensor exhibits sufficient long-time stability and a low susceptibility to sensor fouling.

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Brennan, James F., George I. Zonios, Thomas D. Wang, Richard P. Rava, Gary B. Hayes, Ramachandra R. Dasari, and Michael S. Feld. "Portable Laser Spectrofluorimeter System for in Vivo Human Tissue Fluorescence Studies." Applied Spectroscopy 47, no. 12 (December 1993): 2081–86. http://dx.doi.org/10.1366/0003702934066505.

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A compact, portable spectrofluorimeter which measures broad-band fluorophores with high sensitivity is described. This instrument is specifically designed for acquisition of human tissue autofluorescence spectra in vivo. Pulsed excitation laser light at 337 nm and in the 370–700 nm wavelength range is provided, and the resulting fluorescence can be measured with 10-nm resolution. The system produces single-pulse spectra in human artery wall tissues with a signal-to-noise ratio of 100:1. An optically shielded fiber-optic probe for light delivery and collection permits calibrated intensity information to be obtained.

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Cooper, John B., Philip E. Flecher, Thomas M. Vess, and William T. Welch. "Remote Fiber-Optic Raman Analysis of Xylene Isomers in Mock Petroleum Fuels Using a Low-Cost Dispersive Instrument and Partial Least-Squares Regression Analysis." Applied Spectroscopy 49, no. 5 (May 1995): 586–92. http://dx.doi.org/10.1366/0003702953964147.

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We report the use of a low-cost dispersive Raman instrument with charge-coupled-device (CCD) detection, near-infrared (near-IR) diode laser excitation, and remote fiber-optic sampling to analyze mock petroleum samples which contain high benzene, toluene, ethylbenzene, and xylene (BTEX) concentrations. Partial least-squares regression (PLSR) analysis is used to correlate the individual xylene isomer concentrations to the Raman spectral signal without the use of an internal standard. The resulting PLSR model is used to predict the concentration of individual xylene isomers, and it is found that, at a 95% confidence level, samples containing between ∼1.5 and 15% xylene isomer can be predicted to better than ±0.1% for meta- and para-xylene, and to ±0.15% for ortho-xylene. The use of PLS model leverage plots provides a facile statistical method by which to identify Raman spectra which involve diode laser mode hops or significant fiber backscatter.

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Jones, Thomas P., Shelley J. Coldiron, William J. Deninger, and Marc D. Porter. "A Field-Deployable Dual-Wavelength Fiber-Optic pH Sensor Instrument Based on Solid-State Optical and Electrical Components." Applied Spectroscopy 45, no. 8 (September 1991): 1271–77. http://dx.doi.org/10.1366/0003702914335814.

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Zhou, Bin, and Wei Wang. "Fast Compass Alignment Algorithm of FOG SINS under Sway Condition." Applied Mechanics and Materials 321-324 (June 2013): 2171–76. http://dx.doi.org/10.4028/www.scientific.net/amm.321-324.2171.

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Through research on initial alignment problem of fiber optic gyro SINS in the sway condition, this paper proposed a rapid compass alignment scheme with variable parameters, which can accomplish rapid initial alignment. Firstly, analysted SINS compass alignment principle, and gave a concrete realization method which has the same calculation procedure with full damping navigation algorithm. This method makes the alignment and navigation to use the same set of algorithms, and can effectively reduce algorithm complexity. Simulation and repeatedly sway test results show that the alignment algorithm is effective. The alignment precision and instrument accuracy is consistent, it can meet the requirements of the initial alignment.

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Zhu, Tieyuan, Junzhu Shen, and Eileen R. Martin. "Sensing Earth and environment dynamics by telecommunication fiber-optic sensors: an urban experiment in Pennsylvania, USA." Solid Earth 12, no. 1 (January 28, 2021): 219–35. http://dx.doi.org/10.5194/se-12-219-2021.

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Abstract. Continuous seismic monitoring of the Earth's near surface (top 100 m), especially with improved resolution and extent of data both in space and time, would yield more accurate insights about the effect of extreme-weather events (e.g., flooding or drought) and climate change on the Earth's surface and subsurface systems. However, continuous long-term seismic monitoring, especially in urban areas, remains challenging. We describe the Fiber Optic foR Environmental SEnsEing (FORESEE) project in Pennsylvania, USA, the first continuous-monitoring distributed acoustic sensing (DAS) fiber array in the eastern USA. This array is made up of nearly 5 km of pre-existing dark telecommunication fiber underneath the Pennsylvania State University campus. A major thrust of this experiment is the study of urban geohazard and hydrological systems through near-surface seismic monitoring. Here we detail the FORESEE experiment deployment and instrument calibration, and describe multiple observations of seismic sources in the first year. We calibrate the array by comparison to earthquake data from a nearby seismometer and to active-source geophone data. We observed a wide variety of seismic signatures in our DAS recordings: natural events (earthquakes and thunderstorms) and anthropogenic events (mining blasts, vehicles, music concerts and walking steps). Preliminary analysis of these signals suggests DAS has the capability to sense broadband vibrations and discriminate between seismic signatures of different quakes and anthropogenic sources. With the success of collecting 1 year of continuous DAS recordings, we conclude that DAS along with telecommunication fiber will potentially serve the purpose of continuous near-surface seismic monitoring in populated areas.

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Cuñat, J., F. J. Fortes, L. M. Cabalín, F. Carrasco, M. D. Simón, and J. J. Laserna. "Man-Portable Laser-Induced Breakdown Spectroscopy System for in Situ Characterization of Karstic Formations." Applied Spectroscopy 62, no. 11 (November 2008): 1250–55. http://dx.doi.org/10.1366/000370208786401662.

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This paper reports the development and field testing of a man-portable instrument based on laser-induced breakdown spectrometry (LIBS) for inspection and analysis of speleothems. The 50 mJ of a Q-switched Nd:YAG laser operating at 1064 nm was used to generate a plasma on the sample. Plasma emission was then guided using a fiber-optic cable to a 1/10 m spectrometer equipped with a charge-coupled device (CCD) array detector. Plasma light was automatically processed in order to obtain surface and in-depth information from the speleothems. A field campaign in the interior of Nerja Cave (a large karstic formation in the South of Spain) has been carried out, aimed at evaluating the analytical performance of the instrument when operating in an unfriendly environment. Identification analysis of the speleothems' alteration layers and depth profiles of Sr and Ca is carried out and reported.

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Journal articles on the topic 'Fiber optic instrument'

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