Journal articles: 'Optic Remote Sensing'

1

Glenar, David A., John J. Hillman, Babak Saif, and Jay Bergstralh. "Acousto-optic imaging spectropolarimetry for remote sensing." Applied Optics 33, no. 31 (November 1, 1994): 7412. http://dx.doi.org/10.1364/ao.33.007412.

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Antonelli, Lynn, and Fletcher Blackmon. "Experimental demonstration of remote, passive acousto-optic sensing." Journal of the Acoustical Society of America 116, no. 6 (December 2004): 3393–403. http://dx.doi.org/10.1121/1.1811475.

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Alarie, J. P., D. L. Stokes, W. S. Sutherland, A. C. Edwards, and T. Vo-Dinh. "Intensified Charge Coupled Device-Based Fiber-Optic Monitor for Rapid Remote Surface-Enhanced Raman Scattering Sensing." Applied Spectroscopy 46, no. 11 (November 1992): 1608–12. http://dx.doi.org/10.1366/0003702924926736.

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This paper describes the development of an intensified charge coupled device (ICCD)-based fiber-optic monitor for remote Raman and surface-enhanced Raman (SERS) sensing. Both Raman and SERS data were obtained with the use of a fiber-optic probe design incorporating 20-m optical fibers carrying the Raman signal. Spectra were obtained in 5 milliseconds for Raman and 9 ms for SERS. The proposed system could be used for a highly sensitive portable Raman system for rapid and remote chemical sensing.

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Hühne, Martin, Ursula Eschenauer, and Heinz W. Siesler. "Performance and Selected Applications of an Acousto-Optic Tunable Filter Near-Infrared Spectrometer." Applied Spectroscopy 49, no. 2 (February 1995): 177–80. http://dx.doi.org/10.1366/0003702953963823.

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The design and applications of a near-infrared (near-IR) spectrometer with an acousto-optic tunable filter (AOTF) as monochromator and light fiber optics are described. The aim of this spectrometer is rapid product and reaction control via remote sensing and chemometric data evaluation. Its application and performance are illustrated by the determination of the water content of acetone and by the contact-free temperature measurement of an aqueous solution.

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Liu, Qinhuo, Guangjian Yan, Ziti Jiao, Qing Xiao, Jianguang Wen, Shunlin Liang, Jindi Wang, Crystal Schaaf, and Alan Strahler. "From Geometric-Optical Remote Sensing Modeling to Quantitative Remote Sensing Science—In Memory of Academician Xiaowen Li." Remote Sensing 10, no. 11 (November 8, 2018): 1764. http://dx.doi.org/10.3390/rs10111764.

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The academician Xiaowen Li devoted much of his life to pursuing fundamental research in remote sensing. A pioneer in the geometric-optical modeling of vegetation canopies, his work is held in high regard by the international remote sensing community. He codeveloped the Li–Strahler geometric-optic model, and this paper was selected by a member of the International Society for Optical Engineering (SPIE) milestone series. As a chief scientist, Xiaowen Li led a scientific team that made outstanding advances in bidirectional reflectance distribution modeling, directional thermal emission modeling, comprehensive experiments, and the understanding of spatial and temporal scale effects in remote sensing information, and of quantitative inversions utilizing remote sensing data. In addition to his broad research activities, he was noted for his humility and his dedication in making science more accessible for the general public. Here, the life and academic contributions of Xiaowen Li to the field of quantitative remote sensing science are briefly reviewed.

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Leilabady, P. Akhavan, and M. Corke. "All-fiber-optic remote sensing of temperature employing interferometric techniques." Optics Letters 12, no. 10 (October 1, 1987): 772. http://dx.doi.org/10.1364/ol.12.000772.

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Farahi, F., T. P. Newson, J. D. C. Jones, and D. A. Jackson. "Coherence multiplexing of remote fibre optic fabry-perot sensing system." Optics Communications 65, no. 5 (March 1988): 319–21. http://dx.doi.org/10.1016/0030-4018(88)90094-6.

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Liu, Chun Tong, Yang Zhang, Zhen Xin He, and Hong Cai Li. "Design of Remote Test System for Fiber Bragg Grating Based on LabVIEW." Advanced Materials Research 694-697 (May 2013): 992–96. http://dx.doi.org/10.4028/www.scientific.net/amr.694-697.992.

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As a new type of wavelength modulated fiber optic sensor, Fiber Bragg Grating (FBG) has been widely used in many fields. The majority of FBG demodulation device just detect the absolute wavelength, however, the change of wavelength is often concerned in actual use. For the purpose of realizing the FBG sensing system automated test, using the remote control port of the Q8384 spectrometer and the LabVIEW language to develop the remote automation testing system, and with the friendly interface of FBG sensing test interface. Realized the real-time monitoring and data storage capabilities by the processing of the collecting data and the FBG sensing remote test system is more practical.

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Moreau, Frédérick, Sandrine M. Moreau, Dennis M. Hueber, and Tuan Vo-Dinh. "Fiber-Optic Remote Multisensor System Based on an Acousto-Optic Tunable Filter (AOTF)." Applied Spectroscopy 50, no. 10 (October 1996): 1295–300. http://dx.doi.org/10.1366/0003702963904917.

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This paper describes a new fiber-optic multisensor based on an acousto-optic tunable filter (AOTF) and capable of remote sensing using a multioptical fiber array (MOFA). A two-dimensional charge-coupled device (CCD) was used as a detector, and the AOTF was used as a wavelength selector. Unlike a tunable grating or prism-based monochromator, an AOTF has no moving parts, and an AOTF can be rapidly tuned to any wavelength in its operating range within microseconds. The large aperture of the AOTF allows the optical signal from over 100 fiber-optic sensors to be measured simultaneously. These characteristics, combined with their small size, make AOTFs an important new alternative to conventional monochromators, especially for spectral multisensing and imaging. A prototype fiber-optic multisensor system has been developed, and its feasibility for simultaneous detection of molecular luminescence signal via fiber-optic probes is demonstrated.

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Huston, Alan L., Brian L. Justus, and Tommy L. Johnson. "Fiber‐optic‐coupled, laser heated thermoluminescence dosimeter for remote radiation sensing." Applied Physics Letters 68, no. 24 (June 10, 1996): 3377–79. http://dx.doi.org/10.1063/1.116509.

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11

Beeri, Ofer, Yishai Netzer, Sarel Munitz, Danielle Ferman Mintz, Ran Pelta, Tal Shilo, Alon Horesh, and Shay Mey-tal. "Kc and LAI Estimations Using Optical and SAR Remote Sensing Imagery for Vineyards Plots." Remote Sensing 12, no. 21 (October 22, 2020): 3478. http://dx.doi.org/10.3390/rs12213478.

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Daily or weekly irrigation monitoring conducted per sub-field or management zone is an important factor in vine irrigation decision-making. The objective is to determine the crop coefficient (Kc) and the leaf area index (LAI). Since the 1990s, optic satellite imagery has been utilized for this purpose, yet cloud-cover, as well as the desire to increase the temporal resolution, raise the need to integrate more imagery sources. The Sentinel-1 (a C-band synthetic aperture radar—SAR) can solve both issues, but its accuracy for LAI and Kc mapping needs to be determined. The goals of this study were as follows: (1) to test different methods for integrating SAR and optic sensors for increasing temporal resolution and creating seamless time-series of LAI and Kc estimations; and (2) to evaluate the ability of Sentinel-1 to estimate LAI and Kc in comparison to Sentinel-2 and Landsat-8. LAI values were collected at two vineyards, over three (north plot) and four (south plot) growing seasons. These values were converted to Kc, and both parameters were tested against optic and SAR indices. The results present the two Sentinel-1 indices that achieved the best accuracy in estimating the crop parameters and the best method for fusing the optic and the SAR data. Utilizing these achievements, the accuracy of the Kc and LAI estimations from Sentinel-1 were slightly better than the Sentinel-2′s and the Landsat-8′s accuracy. The integration of all three sensors into one seamless time-series not only increases the temporal resolution but also improves the overall accuracy.

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Wang, Zhongmin, Tianying Chang, Xiangbao Zeng, Haixu Wang, Liyao Cheng, Chongjian Wu, Jiandong Chen, Zhengchun Luo, and Hong-Liang Cui. "Fiber optic multipoint remote methane sensing system based on pseudo differential detection." Optics and Lasers in Engineering 114 (March 2019): 50–59. http://dx.doi.org/10.1016/j.optlaseng.2018.10.013.

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Weyer, L. G., K. J. Becker, and H. B. Leach. "Remote Sensing Fiber Optic Probe NIR Spectroscopy Coupled with Chemometric Data Treatment." Applied Spectroscopy 41, no. 5 (July 1987): 786–90. http://dx.doi.org/10.1366/0003702874448283.

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A near-infrared fiber optic probe remote sensing spectroscopic system has been developed for online multicomponent composition analysis. The Guided Wave Model 200 UV-VIS-NIR spectrophotometer has been evaluated as the base of this system. Multiple linear regression (MLR) software has been combined with data transfer, graphics, and online monitoring programs. The system has been evaluated in plant trials to monitor the composition of mixed alcohol purification streams, mixed solvent distillate, and a fatty acid derivative. The combined use of derivative spectroscopy and MLR data treatment provided good prediction equations for the real-time (20 s) monitoring of the concentrations of several components in moving streams.

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Jing, Li, Che Ying, Jin Meishan, Zhai Yannan, and Ding Changhong. "Application of laser remote sensing technology and super continuous spectrum laser." E3S Web of Conferences 165 (2020): 03002. http://dx.doi.org/10.1051/e3sconf/202016503002.

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Fiber optic super continuous spectrum laser technology is a new technology developed in recent years. It takes into account the advantages of good alignment of laser source, high energy density and wide wavelength range of ordinary white light source, which can not only accurately remote sense distant target, but also obtain hyperspectral information of distant target. Super continuous spectrum of laser radar is a kind of remote sensing monitoring instrument, it can obtain three-dimensional spectral information of the target, and can be accurately detected in the night of distant high spectral information, the all-weather, three-dimensional spectrum detection method with the traditional passive remote sensing compared with single/multiband laser radar technology has incomparable advantages. Based on the development trend of lidar abroad, the development status of super-continuous spectrum lidar in China and the problems in remote sensing detection of oil spill, this paper introduces the feasibility of using super-continuous spectrum laser to monitor oil spill in the sea, which lays a foundation for further research.

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15

Lin, Jie, and Chris W. Brown. "Near-IR Fiber-Optic Temperature Sensor." Applied Spectroscopy 47, no. 1 (January 1993): 62–68. http://dx.doi.org/10.1366/0003702934048424.

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A fiber-optic temperature sensor based on the perturbations of near-IR water bands has been developed. These fiber-optic sensors are very simple and readily fabricated. Models for expressing temperature can be developed by linear regression (LR) of the absorbance at one selected wavenumber, by multilinear regression (MLR) of the absorbances at several selected wavenumbers, or by principal component regression (PCR) using entire spectra. The standard errors of prediction for temperature are 0.53 to 1.64°C for the LR model, 0.22 to 0.85°C for the MLR model, and 0.16 to 0.32°C for the PCR model over a temperature range of 5 to 85°C. Potentially, these fiber-optic sensors can be used in the remote sensing of temperature and in hostile electrical environments.

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16

Heo, Jong, Monica Rodrigues, Steven J. Saggese, and George H. Sigel. "Remote fiber-optic chemical sensing using evanescent-wave interactions in chalcogenide glass fibers." Applied Optics 30, no. 27 (September 20, 1991): 3944. http://dx.doi.org/10.1364/ao.30.003944.

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Garzarella, A., S. B. Qadri, and Dong Ho Wu. "Optimal electro-optic sensor configuration for phase noise limited, remote field sensing applications." Applied Physics Letters 94, no. 22 (June 2009): 221113. http://dx.doi.org/10.1063/1.3152792.

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18

Li, Jiahui, Youxin Zhao, Jiguang Dai, and Hong Zhu. "Coastal Zone Classification Based on Multisource Remote Sensing Imagery Fusion." Journal of Sensors 2018 (September 24, 2018): 1–10. http://dx.doi.org/10.1155/2018/5902318.

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The main objective of this paper was to assess the capability of multisource remote sensing imagery fusion for coastal zone classification. Five scenes of Gaofen- (GF-) 1 optic imagery and four scenes of synthetic aperture radar (SAR) (C-band Sentinel-1 and L-band ALOS-2) imagery were collected and matched. Note that GF-1 is the first satellite of the China high-resolution earth observation system, which acquires multispectral data with decametric spatial resolution, high temporal resolution, and wide coverage. The results showed that based on the comparison of C- and L-band SAR for coastal coverage, it is verified that C band is superior to L band and parameter subsets of σvv0, σvh0, and Dcross can be effectively used for coastal classification. A new fusion method based on the wavelet transform (WT) was also proposed and used for imagery fusion. Statistical values for the mean, entropy, gradient, and correlation coefficient of the proposed method were 67.526, 7.321, 6.440, and 0.955, respectively. We therefore conclude that the result of our proposed method is superior to GF-1 imagery and traditional HIS fusion results. Finally, the classification output was determined along with an assessment of classification accuracy and kappa coefficient. The kappa coefficient and overall accuracy of the classification were 0.8236 and 85.9774%, respectively, so the proposed fusion method had a satisfying performance for coastal coverage mapping.

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Lowry, S., T. May, A. Bornstein, Y. Weissman, R. Harman, and I. Tugenthaft. "New Accessory for Characterizing Optical Fibers with an FT-IR Spectrometer." Applied Spectroscopy 48, no. 7 (July 1994): 852–56. http://dx.doi.org/10.1366/0003702944030017.

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An accessory has been designed for FT-IR spectroscopy that can be used to measure the optical properties of fiber-optic cables or serve as an interface for remote sensing probes that use fiber optics. This accessory utilizes compound parabolic concentrators (CPCs) to focus the energy from the spectrometer into the optical fiber and to also refocus the energy returning to the spectrometer onto the detector. The design was optimized for the high acceptance angle of chalcogenide mid-IR fibers. However, the use of nonimaging concentrators yields an all-reflecting system that can be used to characterize fibers with different spectral transmission ranges. This accessory has been used to investigate the spectral response, cladding effects, and impurities in various optical fibers.

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20

Louch, Jeff, and J. D. Ingle. "Experimental comparison of single- and double-fiber configurations for remote fiber-optic fluorescence sensing." Analytical Chemistry 60, no. 22 (November 15, 1988): 2537–40. http://dx.doi.org/10.1021/ac00173a023.

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Chan, K., H. Ito, H. Inaba, and T. Furuya. "10 km-long fibre-optic remote sensing of CH4 gas by near infrared absorption." Applied Physics B Photophysics and Laser Chemistry 38, no. 1 (September 1985): 11–15. http://dx.doi.org/10.1007/bf00691764.

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Chausov, Y. V., and A. S. Molchanov. "Software and methodical complex for image processing during flight tests of iconic optic-and-electronic systems." Geodesy and Cartography 955, no. 1 (February 20, 2020): 26–33. http://dx.doi.org/10.22389/0016-7126-2020-955-1-26-33.

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The authors present a method for determining the modulation transfer function of iconic opticand-electronic systems for remote sensing the Earth, developed to assess their quality during flight tests and propose a specialized digital image processing software package that implements an algorithm for determining the modulation transfer function. The adequacy of the developed method and the functioning of a specialized software complex for processing digital images is confirmed by satisfactory convergence of the analytical system and the aviation multi-functional optical-electronic one derived from the flight testing the functions of the modulation transfer. The features of mathematical modeling iconic optical-electronic systems of the Earth remote sensing during the tests are presented. The authors present the structure of the mathematical model of iconic optoelectronic systems, which reflects the main links that affect the quality of the image formed. The main quality criteria used in practice for evaluating iconic optical-electronic systems using the mathematical model are presented.

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Wei, Yu Bin, Xu You Wang, Min Xin, Tong Yu Liu, and Chang Wang. "Fiber Optic Temperature and Gas Concentration Sensor for Mine Goaf Area Inner Detecting." Advanced Materials Research 524-527 (May 2012): 302–5. http://dx.doi.org/10.4028/www.scientific.net/amr.524-527.302.

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Spontaneous combustion in coal goaf area is one of major disasters in coal mines. Detection technology based on signature Gas and Temperature is the primary means of spontaneous combustion forecasting of coal goaf area. A real-time remote fire detection system is proposed based on tunable diode laser absorption spectroscopy technology and FBG temperature sensing technology, to achieve valid detect of gas concentration and temperature. The System include fiber mathen concentration sensor and fiber temperature sensor based FBG. The system achieved remote on-line monitoring of gas concentration and temperature in mine goaf, meet the fire forecast need for Coal goaf area. There are obvious advantages Compared with the existing beam tube monitoring system in coal mine.

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Kim, Rinah, Sang Bin Lee, Jae Wook Kim, and Joo Hyun Moon. "Development and Comparison of Fiber-Optic Beta Radiation Sensors with Different Diameters of Their Sensing Probes." Journal of Sensors 2017 (2017): 1–5. http://dx.doi.org/10.1155/2017/1452765.

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A fiber-optic radiation sensor (FORS) was developed for remote and real-time measurements of beta radiation from radioactive-contaminated soil. The sensing probe consisted of a bundle of organic scintillators and a mixture of epoxy resin to improve the detection efficiency. The measurement system consisted of a sensing probe with an aluminium foil reflector, a transmitting plastic optical fiber, and a light-measuring system comprising a photomultiplier tube, a preamplifier, a multichannel analyzer, and a laptop computer. Several sensing probes, whose dead-end diameters were 26 mm (bundle type I), 36 mm (bundle type II), and 46 mm (bundle type III), were prepared and characterized to identify the best sensing probe in terms of its radiation detection efficiency. The reproducibility of the FORS for the measurement of beta radiation was confirmed using a χ2-test. The measurements showed that the FORS sensing probe with a diameter 46 mm has the best detection performance.

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Bunker, Jesse, Raja M. Nagisetty, and Jeremy Crowley. "sUAS Remote Sensing to Evaluate Geothermal Seep Interactions with the Yellowstone River, Montana, USA." Remote Sensing 13, no. 2 (January 6, 2021): 163. http://dx.doi.org/10.3390/rs13020163.

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Small unmanned aerial systems (sUAS) are becoming increasingly popular due to their affordability and logistical ease for repeated surveys. While sUAS-based remote sensing has many applications in water resource management, their applicability and limitations in fluvial settings is not well defined. This study uses a combined thermal-optic sUAS to monitor the seasonal geothermal influence of a 1-km-long reach of the Yellowstone River, paired with in-situ streambed temperature profiles to evaluate geothermal seep interactions with Yellowstone River in Montana, USA. Accurate river water surface elevation along the shoreline was estimated using structure from motion (SfM) photogrammetry digital surface models (DSMs); however, water surface elevations were unreliable in the main river channel. Water temperature in thermal infrared (TIR) orthomosaics was accurate in temperature ranges of tens of degrees (>≈30 °C), but not as accurate in temperature ranges of several degrees (>≈15 °C) as compared to in-situ water temperature measurements. This allowed for identification of geothermal features but limited the ability to identify small-scale temperature changes due to river features, such as pools and riffles. The study concludes that rivers with an average width greater than or equal to 123% of the ground area covered by a TIR image will be difficult to study using structure from motion photogrammetry, given Federal Aviation Administration (FAA) altitude restrictions and sensor field of view. This study demonstrates the potential of combined thermal-optic sUAS systems to collect data over large river systems, and when combined with in-situ measurements, can further increase the sUAS utility in identifying river characteristics.

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Challener, William A., Ansas M. Kasten, Sachin Dekate, Dimitri Dylov, Reza Ghandi, Renato Guida, S. M. Hasan, Thaddeus Czauski, Russell Craddock, and Roger Jones. "Multipoint Pressure and Temperature Sensing Fiber Optic Cable for Monitoring CO2 Sequestration." MRS Advances 1, no. 21 (2016): 1501–12. http://dx.doi.org/10.1557/adv.2016.119.

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ABSTRACTA highly accurate multi-point pressure measurement system based on MEMS pressure sensors spliced into a fiber optic cable and suitable for downhole deployment in a CO2 sequestration well was designed, developed and tested in the laboratory. An interrogator system based on a pulsed laser excitation was shown to be capable of multiple (potentially 60+) point sensor measurements on a single fiber. The interrogator was interfaced with the GE PredixTM industrial internet to demonstrate a remote monitoring system. Sensor packages were fabricated and tested at high temperatures and pressures in supercritical CO2. Environmental and stress testing of the sensor components and package indicated areas in which the design of the package should be further improved.

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Barbillat, J., P. Dhamelincourt, M. Delhaye, and E. Da Silva. "Raman confocal microprobing, imaging and fibre-optic remote sensing: A further step in molecular analysis." Journal of Raman Spectroscopy 25, no. 1 (January 1994): 3–11. http://dx.doi.org/10.1002/jrs.1250250103.

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Lim, Geunsik, Tariq Manzur, and Aravinda Kar. "Laser-Doped SiC as Wireless Remote Gas Sensor Based on Semiconductor Optics." Materials Science Forum 717-720 (May 2012): 1195–98. http://dx.doi.org/10.4028/www.scientific.net/msf.717-720.1195.

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An uncooled SiC-based electro-optic device is developed for gas sensing applications. P-type dopants Ga, Sc, P and Al are incorporated into an n-type crystalline 6H-SiC substrate by a laser doping technique for sensing CO2, CO, NO2 and NO gases, respectively. Each dopant creates an acceptor energy level within the bandgap of the substrate so that the energy gap between this acceptor level and the valence band matches the quantum of energy emitted by the gas of interest. The photons of the gas excite electrons from the valence band to the acceptor level, which alters the electron density in these two states. Consequently, the refractive index of the substrate changes, which, in turn, modifies the reflectivity of the substrate. This change in reflectivity represents the optical signal of the sensor, which is probed remotely with a laser such as a helium-neon laser. Although the midwave infrared (3-5 mm) band is studied in this paper, the approach is applicable to other spectral bands.

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Esfahani Monfared, Yashar. "Overview of Recent Advances in the Design of Plasmonic Fiber-Optic Biosensors." Biosensors 10, no. 7 (July 9, 2020): 77. http://dx.doi.org/10.3390/bios10070077.

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Plasmonic fiber-optic biosensors combine the flexibility and compactness of optical fibers and high sensitivity of nanomaterials to their surrounding medium, to detect biological species such as cells, proteins, and DNA. Due to their small size, accuracy, low cost, and possibility of remote and distributed sensing, plasmonic fiber-optic biosensors are promising alternatives to traditional methods for biomolecule detection, and can result in significant advances in clinical diagnostics, drug discovery, food process control, disease, and environmental monitoring. In this review article, we overview the key plasmonic fiber-optic biosensing design concepts, including geometries based on conventional optical fibers like unclad, side-polished, tapered, and U-shaped fiber designs, and geometries based on specialty optical fibers, such as photonic crystal fibers and tilted fiber Bragg gratings. The review will be of benefit to both engineers in the field of optical fiber technology and scientists in the fields of biosensing.

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Lee, Hoon-Keun, Jaeyul Choo, Gangsig Shin, and Joonyoung Kim. "Long-Reach DWDM-Passive Optical Fiber Sensor Network for Water Level Monitoring of Spent Fuel Pool in Nuclear Power Plant." Sensors 20, no. 15 (July 29, 2020): 4218. http://dx.doi.org/10.3390/s20154218.

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This paper presents a passive optical fiber sensor network based on the dense wavelength division multiplexing (DWDM) to remotely monitor the water level of the spent fuel pool in nuclear power plants. In states of emergency, such as a tsunami, safety information must be secured for rapid response, in spite of all power losses in the plant. We consider the proposed passive sensor network to be one of the best solutions that is able to provide the remote (more than tens of kilometers) monitoring station with the highly reliable on-site information. The principle of water level measurement is based on the change of Fresnel reflection power coefficient at sensing units, which are installed according to the water levels in a row. The sensing units that play the role of reflector and modulator at the same time are connected to an arrayed waveguide grating (AWG) for DWDM. By measuring the spectrum of the optical signal transferred from the sensing units, the water level can be determined in real-time. However, in the remote sensing, the system performance can be seriously degraded due to the Rayleigh Back-Scattering (RBS) of the seeded amplified spontaneous emission (ASE) light that is induced at the fiber-optic link. As such, we investigate the effect of RBS on the remote (more than tens of kilometers) sensing performance of the proposed network. Following the theoretical analysis, we propose a simple network configuration to overcome the RBS issue by utilizing two different transmission paths: one for downstream of the ASE seed light, and the other for upstream of the optical signals coming from the sensing units. Based on the proposed configuration, the maximum sensing distance can be increased up to 42.5 km without the support of any optical amplifier.

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Atasever, U. H., P. Civicioglu, E. Besdok, and C. Ozkan. "A New Unsupervised Change Detection Approach Based On DWT Image Fusion And Backtracking Search Optimization Algorithm For Optical Remote Sensing Data." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XL-7 (September 19, 2014): 15–18. http://dx.doi.org/10.5194/isprsarchives-xl-7-15-2014.

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Change detection is one of the most important subjects of remote sensing discipline. In this paper, a new unsupervised change detection approach is proposed for multi-temporal remotely sensed optic imagery. This approach does not require any prior information about changed and unchanged pixels. The approach is based on Discrete Wavelet Transform (DWT) based image fusion and Backtracking Search Optimization Algorithm (BSA). In the first step of the approach, absolute-valued difference image and absolute-valued log-ratio image is calculated from co-registered and radiometrically corrected multi-temporal images. Then, these difference images are fused using DWT. The fused image is filtered by median filter for edge information preservation and by wiener filter for image smoothing. Then, a min-max normalization is applied to the filtered data. The normalized data is clustered into two groups with BSA as changed and unchanged pixels by minimizing an objective function, unlike classical methods using CVA, PCA, FCM or K-means techniques. To show effectiveness of proposed approach, two remote sensing data sets, Sardinia and Mexico, are used. False Alarm, Missed Alarm, Total Alarm and Total Error Rate are selected as performance criteria to evaluate the effectiveness of new approach using ground truth images. Experimental results show that proposed approach is effective for unsupervised change detection of optical remote sensing data.

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Zhang, Meng, Yan Ru Chen, Ling Fei Xu, and Yong Qing Wang. "A Novel Optic Senor for Real-Time Metal Analysis in the BOF Steelmaking Process." Advanced Materials Research 156-157 (October 2010): 1594–97. http://dx.doi.org/10.4028/www.scientific.net/amr.156-157.1594.

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A fiber optic senor for carbon content measurement of the molten steel in a basic oxygen furnace (BOF) is described. The sensor includes a fiber optic cable for transmission of the optical radiation from the radiation collection head to the multi-wavelength detection unit located in remote area from a furnace. The radiation collection head includes a telephoto lens aimed at the furnace mouth to collect, and thus enhance, the effective radiant energy emitted from the hostile environment adjacent a furnace as well as to reduce spurious radiations from other nearby furnaces. The detection unit based on emission spectroscopy converts the radiations into digital signals and the signal information processed to determine the carbon content of the steel contained in the metallurgical furnace. The Preliminary results after online carbon content sensing are discussed.

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Hassan, Moinuddin, Xin Tan, Elissa Welle, and Ilko Ilev. "Fiber-optic Fourier transform infrared spectroscopy for remote label-free sensing of medical device surface contamination." Review of Scientific Instruments 84, no. 5 (May 2013): 053101. http://dx.doi.org/10.1063/1.4803182.

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Belz, Mathias, Peter Dress, Karl-F. Klein, William J. O. Boyle, Hilmar Franke, and Kenneth T. V. Grattan. "Liquid core waveguide with fiber optic coupling for remote pollution monitoring in the deep ultraviolet." Water Science and Technology 37, no. 12 (June 1, 1998): 279–84. http://dx.doi.org/10.2166/wst.1998.0552.

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A new combination of silica fibres, highly transparent in the ultraviolet (UV) and showing long term stability, combined with a teflon-coated liquid-core waveguide (LCW) is presented for remote sensing in the deep UV, for monitoring one of the major pollutants, nitrates, in water, but with potentially wider applicability. The arrangement exhibits low spectral loss in the range between wavelengths of 200 nm and 400 nm and can be used for analytical investigations to determine small concentrations of such impurities in water. The operation of the optical system to achieve guidance of UV light below a wavelength of 250 nm for fibre optic sensors is discussed. With an optical pathlength of 203 mm, nitrate concentrations as low as 22 μg/l could be detected.

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Wilson, Glenn A., Mark E. Willis, and Andreas Ellmauthaler. "Evaluating 3D and 4D DAS VSP image quality of subsea carbon storage." Leading Edge 40, no. 4 (April 2021): 261–66. http://dx.doi.org/10.1190/tle40040261.1.

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In all carbon capture, utilization, and storage (CCUS) projects, monitoring, verification, and accounting is required to span short to long periods to ensure plume extents and geologic integrity meet operational and regulatory objectives. Fiber-optic cables permanently deployed in the completions of injector wells enable time-lapse (4D) vertical seismic profile (VSP) imaging using distributed acoustic sensing (DAS). Most CCUS projects are onshore, and the majority of those utilize supercritical CO2 flooding for enhanced oil recovery (EOR). In these cases, fiber-optic installations, acquisition, and analysis are relatively straightforward. Offshore transport and storage projects, whether for EOR or sequestration in saline aquifers, may utilize subsea wells wherein fiber-optic deployment is not as straightforward. Unlike dry-tree wells, DAS of subsea wells requires advanced optical engineering solutions to compensate for the reduced acoustic bandwidth, optical losses, and back reflections accumulated through umbilicals, multiple wet- and dry-mate optical connectors, splices, optical feedthrough systems, and downhole fibers. In this paper, we simulate VSP shot records of a carbon storage site for a variety of proposed subsea DAS concepts and evaluate the 3D and 4D seismic image quality of each using Kirchhoff migration of upgoing seismic wavefields with their expected signal-to-noise ratios. We normalize interrogator performance, so we are evaluating the sensing topology only. We show that a subsea fiber topology consisting of dual transmission fibers, a remote circulator with selective amplification of the backscattered light, and enhanced backscatter sensing fiber results in high-quality seismic images suitable for both 3D and 4D VSPs of carbon storage.

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Kurth, A. M., N. Dawes, J. Selker, and M. Schirmer. "Autonomous distributed temperature sensing for long-term heated applications in remote areas." Geoscientific Instrumentation, Methods and Data Systems Discussions 2, no. 2 (October 22, 2012): 855–73. http://dx.doi.org/10.5194/gid-2-855-2012.

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Abstract. Distributed Temperature Sensing (DTS) is a fiber-optical method enabling simultaneous temperature measurements over long distances. Electrical resistance heating of the metallic components of the fiber-optic cable provides information on the thermal characteristics of the cable's environment, providing valuable insight into processes occurring in the surrounding medium, such as groundwater-surface water interactions, dam stability or soil moisture. Until now, heated applications required direct handling of the DTS instrument by a researcher, rendering long-term investigations in remote areas impractical due to the often difficult and time-consuming access to the field site. Remote-control and automation of the DTS instrument and heating processes, however, resolve the issue with difficult access. The data can also be remotely accessed and stored on a central database. The power supply can be grid-independent, although significant infrastructure investment is required here due to high power consumption during heated applications. Solar energy must be sufficient even in worst case scenarios, e.g. during long periods of intense cloud cover, to prevent system failure due to energy shortage. In combination with storage batteries and a low heating frequency, e.g. once per day or once per week (depending on the season and the solar radiation on site), issues of high power consumption may be resolved. Safety regulations dictate adequate shielding and ground-fault protection, to safeguard animals and humans from electricity and laser sources. In this paper the autonomous DTS system is presented to allow research with heated applications of DTS in remote areas for long-term investigations of temperature distributions in the environment.

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Kurth, A. M., N. Dawes, J. Selker, and M. Schirmer. "Autonomous distributed temperature sensing for long-term heated applications in remote areas." Geoscientific Instrumentation, Methods and Data Systems 2, no. 1 (February 7, 2013): 71–77. http://dx.doi.org/10.5194/gi-2-71-2013.

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Abstract. Distributed temperature sensing (DTS) is a fiber-optical method enabling simultaneous temperature measurements over long distances. Electrical resistance heating of the metallic components of the fiber-optic cable provides information on the thermal characteristics of the cable's environment, providing valuable insight into processes occurring in the surrounding medium, such as groundwater–surface water interactions, dam stability or soil moisture. Until now, heated applications required direct handling of the DTS instrument by a researcher, rendering long-term investigations in remote areas impractical due to the often difficult and time-consuming access to the field site. Remote control and automation of the DTS instrument and heating processes, however, resolve the issue with difficult access. The data can also be remotely accessed and stored on a central database. The power supply can be grid independent, although significant infrastructure investment is required here due to high power consumption during heated applications. Solar energy must be sufficient even in worst case scenarios, e.g. during long periods of intense cloud cover, to prevent system failure due to energy shortage. In combination with storage batteries and a low heating frequency, e.g. once per day or once per week (depending on the season and the solar radiation on site), issues of high power consumption may be resolved. Safety regulations dictate adequate shielding and ground-fault protection, to safeguard animals and humans from electricity and laser sources. In this paper the autonomous DTS system is presented to allow research with heated applications of DTS in remote areas for long-term investigations of temperature distributions in the environment.

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38

Pomeroy, Robert S., Mark E. Baker, M. Bonner Denton, and Andrew G. Dickson. "Scientifically Operated CCD-Based Spectroscopic System for High-Precision Spectrometric Determinations of Seawater." Applied Spectroscopy 49, no. 12 (December 1995): 1729–36. http://dx.doi.org/10.1366/0003702953965939.

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The application of an aberration-corrected imaging spectrograph with the use of fiber-optic inputs and a charge-coupled device detector to produce a sensitive, flexible, and rugged spectroscopic system capable of employment in remote sensing and field applications is presented. This investigation focuses on the optical system design, detector characteristics, and modes of operation that will result in a field instrument capable of both sensitive fluorescence and high-precision absorbance measurements. Evaluation of the optical system used the spectroscopic determination of seawater pH as the test case. Spectral measurements were made with the use of thymol blue as a pH indicator for absorbance and 7-hydroxy-coumarin as the fluorescence pH indicator. This system displayed excellent precision for both absorbance and fluorescence analyses; RSDs for absorbance and fluorescence of ±0.00065 and ±0.0015 in pH, respectively, were experimentally obtained. These findings, along with the advantages of the area array detector to provide simultaneous multiwavelength, multianalyte spectral analysis in a single, rugged optical system, make a strong case for the application of scientifically operated solid-state detector systems to remote sensing and field instrumentation.

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Yan, Yi Fei, Ming Bai, Chen Guang Xie, and Jun Gang Miao. "The Principle of the Electro-Optic System in Passive Synthetic Aperture Lmging." Applied Mechanics and Materials 121-126 (October 2011): 2348–52. http://dx.doi.org/10.4028/www.scientific.net/amm.121-126.2348.

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As the synthetic aperture has been widely used in remote sensing and imaging system. Various methods have been used to enhance the imgaing speed of the system. Optical method has been proved to have the high imaging speed in processing microwave signals. The received signal can be modulated in optical carrier by the electro-optic amplitude modulation. The optical signal is processed by relevant optical instruments. The article compares the new electro-optic imaging system with the original system. The principle of the new system has been proved to be similar with the original system. The structure of the new system has been verified to have the possibility to realize real-time imaging. The key point of the new system has been analysed and the main challenge in the new system has been checked in the article.

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Rajeev, Pathmanathan, Jayantha Kodikara, Wing Kong Chiu, and Thomas Kuen. "Distributed Optical Fibre Sensors and their Applications in Pipeline Monitoring." Key Engineering Materials 558 (June 2013): 424–34. http://dx.doi.org/10.4028/www.scientific.net/kem.558.424.

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Health monitoring of civil infrastructure systems has recently emerged as a powerful tool for condition assessment of infrastructure performance. With the widespread use of modern telecommunication technologies, structures could be monitored periodically from a central station located several kilometres away from the field. This remote capability allows immediate damage detection, so that necessary actions are taken to reduce the risk. Optical fiber sensors offer a relatively new technology for monitoring the performance of spatially distributed structures such as pipelines. In this regards, several commercially available strain and temperature sensing equipment such as discrete FBGs (Fibre Bragg Gratings) and fully distributed sensing techniques such as Raman DTS (distributed temperature sensor) and Brillouin Optical Time Domain Reflectometry (BOTDR) typically offer sensing lengths of the order of 100 km's. Distributed fiber optic sensing offers the ability to measure temperatures and/or strains at thousands of points along a single fiber. In this paper, the authors will give a brief overview of these optical fiber technologies, outline potential applications of these technologies for geotechnical engineering applications and experience in utilising BOTDR in water pipeline monitoring application.

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Tenge, Brad, B. R. Buchanan, and D. E. Honigs. "Calibration in the Fiber Optic Region of the Near-Infrared." Applied Spectroscopy 41, no. 5 (July 1987): 779–85. http://dx.doi.org/10.1366/0003702874448409.

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Chemical sensing in remote, hostile environments is possible with optical fiber technology. Telecommunications optical fiber transmits light in the near-infrared region. The least amount of attenuation of transmitted power is between 1050 nm and 1600 nm. It is a natural step to apply near-infrared analysis techniques to data remotely collected over optical fibers. A feasibility study is conducted to see how well calibration techniques, Multiple Linear Regression with either Step-up search or All Possible Combinations search, perform in the fiber optic region of the near-infrared. Calibration in the 1131–1531 nm region is compared to calibration in the 1131–2531 nm region. The latter region is considered more information-rich than the former. In spite of this, examination of the predictive power of calibration models formed strictly from fiberoptic-region absorbance data indicates that this region contains useful analytical informaton.

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An, Yulong, Yanmei Zhang, Haichao Guo, and Jing Wang. "Compressive Sensing Based Three-Dimensional Imaging Method with Electro-Optic Modulation for Nonscanning Laser Radar." Symmetry 12, no. 5 (May 6, 2020): 748. http://dx.doi.org/10.3390/sym12050748.

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Low-cost Laser Detection and Ranging (LiDAR) is crucial to three-dimensional (3D) imaging in applications such as remote sensing, target detection, and machine vision. In conventional nonscanning time-of-flight (TOF) LiDAR, the intensity map is obtained by a detector array and the depth map is measured in the time domain which requires costly sensors and short laser pulses. To overcome such limitations, this paper presents a nonscanning 3D laser imaging method that combines compressive sensing (CS) techniques and electro-optic modulation. In this novel scheme, electro-optic modulation is applied to map the range information into the intensity of echo pulses symmetrically and the measurements of pattern projection with symmetrical structure are received by the low bandwidth detector. The 3D imaging can be extracted from two gain modulated images that are recovered by solving underdetermined inverse problems. An integrated regularization model is proposed for the recovery problems and the minimization functional model is solved by a proposed algorithm applying the alternating direction method of multiplier (ADMM) technique. The simulation results on various subrates for 3D imaging indicate that our proposed method is feasible and achieves performance improvement over conventional methods in systems with hardware limitations. This novel method will be highly valuable for practical applications with advantages of low cost and flexible structure at wavelengths beyond visible spectrum.

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Fuglerud, Silje S., Karolina Milenko, Astrid Aksnes, and Dag R. Hjelme. "Surface-Enhanced Absorption Spectroscopy for Optical Fiber Sensing." Materials 13, no. 1 (December 19, 2019): 34. http://dx.doi.org/10.3390/ma13010034.

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Visible and near-infrared spectroscopy are widely used for sensing applications but suffer from poor signal-to-noise ratios for the detection of compounds with low concentrations. Enhancement by surface plasmon resonance is a popular technique that can be utilized to increase the signal of absorption spectroscopy due to the increased near-field created close to the plasmons. Despite interest in surface-enhanced infrared absorption spectroscopy (SEIRAS), the method is usually applied in lab setups rather than real-life sensing situations. This study aimed to achieve enhanced absorption from plasmons on a fiber-optic probe and thus move closer to applications of SEIRAS. A tapered coreless fiber coated with a 100 nm Au film supported signal enhancement at visible wavelengths. An increase in absorption was shown for two dyes spanning concentrations from 5 × 10−8 mol/L to 8 × 10−4 mol/L: Rhodamine 6G and Crystal Violet. In the presence of the Au film, the absorbance signal was 2–3 times higher than from an identically tapered uncoated fiber. The results confirm that the concept of SEIRAS can be implemented on an optical fiber probe, enabling enhanced signal detection in remote sensing applications.

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Vitoria, Ignacio, Carlos Ruiz Zamarreño, Aritz Ozcariz, and Ignacio R. Matias. "Fiber Optic Gas Sensors Based on Lossy Mode Resonances and Sensing Materials Used Therefor: A Comprehensive Review." Sensors 21, no. 3 (January 22, 2021): 731. http://dx.doi.org/10.3390/s21030731.

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Pollution in cities induces harmful effects on human health, which continuously increases the global demand of gas sensors for air quality control and monitoring. In the same manner, the industrial sector requests new gas sensors for their productive processes. Moreover, the association between exhaled gases and a wide range of diseases or health conditions opens the door for new diagnostic applications. The large number of applications for gas sensors has permitted the development of multiple sensing technologies. Among them, optical fiber gas sensors enable their utilization in remote locations, confined spaces or hostile environments as well as corrosive or explosive atmospheres. Particularly, Lossy Mode Resonance (LMR)-based optical fiber sensors employ the traditional metal oxides used for gas sensing purposes for the generation of the resonances. Some research has been conducted on the development of LMR-based optical fiber gas sensors; however, they have not been fully exploited yet and offer optimal possibilities for improvement. This review gives the reader a complete overview of the works focused on the utilization of LMR-based optical fiber sensors for gas sensing applications, summarizing the materials used for the development of these sensors as well as the fabrication procedures and the performance of these devices.

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Lin, Jie, and Chris W. Brown. "Simultaneous Determination of Physical and Chemical Properties of Sodium Chloride Solutions by near Infrared Spectroscopy." Journal of Near Infrared Spectroscopy 1, no. 2 (March 1993): 109–20. http://dx.doi.org/10.1255/jnirs.14.

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Near infrared (NIR) spectroscopy has been investigated as a new technique for the simultaneous determination of physical and chemical properties of NaCl solutions. The spectra of NaCl solutions (0 to 5 M) were measured with cuvettes in the 1100–2500 nm and 680–1230 nm regions at temperatures between 23.0 and 28.5°C, and with a fibre-optic probe in the 1100–1870 nm region at room temperature (23.0 ± 0.5°C). These spectra were correlated with various properties of NaCl solutions by principal component regression (PCR) and multilinear regression (MLR) models. The properties studied include water concentration, density, refractive index, relative viscosity, freezing point depression, osmolality, electrical conductance and activity coefficient of NaCl. Very good correlations were found between the NIR predicted values and literature values. The results of this study demonstrate that several properties of NaCl solutions can be determined simultaneously with NIR spectroscopy. Remote sensing of the properties can be performed with the use of a fibre-optic probe.

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Ma, Chao-Tsung, Cheng-Ling Lee, and Yan-Wun You. "Design and Implementation of a Novel Measuring Scheme for Fiber Interferometer Based Sensors." Sensors 19, no. 19 (September 21, 2019): 4080. http://dx.doi.org/10.3390/s19194080.

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This paper presents a novel measuring scheme for fiber interferometer (FI) based sensors. With the advantages of being small sizes, having high sensitivity, a simple structure, good durability, being easy to integrate fiber optic communication and having immunity to electromagnetic interference (EMI), FI based sensing devices are suitable for monitoring remote system states or variations in physical parameters. However, the sensing mechanism for the interference spectrum shift of FI based sensors requires expensive equipment, such as a broadband light source (BLS) and an optical spectrum analyzer (OSA). This has strongly handicapped their wide application in practice. To solve this problem, we have, for the first time, proposed a smart measuring scheme, in which a commercial laser diode (LD) and a photodetector (PD) are used to detect the equivalent changes of optical power corresponding to the variation in measuring parameters, and a signal processing system is used to analyze the optical power changes and to determine the spectrum shifts. To demonstrate the proposed scheme, a sensing device on polymer microcavity fiber Fizeau interferometer (PMCFFI) is taken as an example for constructing a measuring system capable of long-distance monitoring of the temperature and relative humidity. In this paper, theoretical analysis and fundamental tests have been carried out. Typical results are presented to verify the feasibility and effectiveness of the proposed measuring scheme, smartly converting the interference spectrum shifts of an FI sensing device into the corresponding variations of voltage signals. With many attractive features, e.g., simplicity, low cost, and reliable remote-monitoring, the proposed scheme is very suitable for practical applications.

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Hu, Deming, Zhiyuan Xu, Junqiu Long, Peng Xiao, Lili Liang, Lipeng Sun, Hao Liang, Yang Ran, and Bai-Ou Guan. "Label-Free and Reproducible Chemical Sensor Using the Vertical-Fluid-Array Induced Optical Fiber Long Period Grating (VIOLIN)." Sensors 20, no. 12 (June 17, 2020): 3415. http://dx.doi.org/10.3390/s20123415.

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Fiber optical refractometers have gained a substantial reputation in biological and chemical sensing domain regarding their label-free and remote-operation working mode. However, the practical breakthrough of the fiber optical bio/chemosensor is impeded by a lack of reconfigurability as well as the explicitness of the determination between bulk and surface refractive indices. In this letter, we further implement the highly flexible and reproducible long period grating called “VIOLIN” in chemical sensing area for the demonstration of moving those obstacles. In this configuration, the liquid is not only leveraged as the chemical carrier but also the periodic modulation of the optical fiber to facilitate the resonant signal. The thiol compound that is adsorbed by the fluidic substrate can be transduced to the pure alteration of the bulk refractive index of the liquid, which can be sensitively perceived by the resonant drift. Taking advantage of its freely dismantled feature, the VIOLIN sensor enables flexible reproduction and high throughput detection, yielding a new vision to the fiber optic biochemical sensing field.

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Grigorevskiĭ, V. I., and Ya A. Tezadov. "Multichannel fiber-optic amplifier at the wavelength of 1653 nm for lidar remote sensing of atmospheric methane concentrations." Journal of Optical Technology 87, no. 7 (July 1, 2020): 430. http://dx.doi.org/10.1364/jot.87.000430.

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Dexheimer, Darielle, Martin Airey, Erika Roesler, Casey Longbottom, Keri Nicoll, Stefan Kneifel, Fan Mei, R. Giles Harrison, Graeme Marlton, and Paul D. Williams. "Evaluation of ARM tethered-balloon system instrumentation for supercooled liquid water and distributed temperature sensing in mixed-phase Arctic clouds." Atmospheric Measurement Techniques 12, no. 12 (December 20, 2019): 6845–64. http://dx.doi.org/10.5194/amt-12-6845-2019.

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Abstract. A tethered-balloon system (TBS) has been developed and is being operated by Sandia National Laboratories (SNL) on behalf of the U.S. Department of Energy's (DOE) Atmospheric Radiation Measurement (ARM) User Facility in order to collect in situ atmospheric measurements within mixed-phase Arctic clouds. Periodic tethered-balloon flights have been conducted since 2015 within restricted airspace at ARM's Advanced Mobile Facility 3 (AMF3) in Oliktok Point, Alaska, as part of the AALCO (Aerial Assessment of Liquid in Clouds at Oliktok), ERASMUS (Evaluation of Routine Atmospheric Sounding Measurements using Unmanned Systems), and POPEYE (Profiling at Oliktok Point to Enhance YOPP Experiments) field campaigns. The tethered-balloon system uses helium-filled 34 m3 helikites and 79 and 104 m3 aerostats to suspend instrumentation that is used to measure aerosol particle size distributions, temperature, horizontal wind, pressure, relative humidity, turbulence, and cloud particle properties and to calibrate ground-based remote sensing instruments. Supercooled liquid water content (SLWC) sondes using the vibrating-wire principle, developed by Anasphere Inc., were operated at Oliktok Point at multiple altitudes on the TBS within mixed-phase clouds for over 200 h. Sonde-collected SLWC data were compared with liquid water content derived from a microwave radiometer, Ka-band ARM zenith radar, and ceilometer at the AMF3, as well as liquid water content derived from AMF3 radiosonde flights. The in situ data collected by the Anasphere sensors were also compared with data collected simultaneously by an alternative SLWC sensor developed at the University of Reading, UK; both vibrating-wire instruments were typically observed to shed their ice quickly upon exiting the cloud or reaching maximum ice loading. Temperature sensing measurements distributed with fiber optic tethered balloons were also compared with AMF3 radiosonde temperature measurements. Combined, the results indicate that TBS-distributed temperature sensing and supercooled liquid water measurements are in reasonably good agreement with remote sensing and radiosonde-based measurements of both properties. From these measurements and sensor evaluations, tethered-balloon flights are shown to offer an effective method of collecting data to inform and constrain numerical models, calibrate and validate remote sensing instruments, and characterize the flight environment of unmanned aircraft, circumventing the difficulties of in-cloud unmanned aircraft flights such as limited flight time and in-flight icing.

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Steffen, Ray L., and Fred E. Lytle. "Remote sensing in an optically dense environment by using two-photon excited fluorescence and a single multimode fiber optic." Analytica Chimica Acta 200 (1987): 491–502. http://dx.doi.org/10.1016/s0003-2670(00)83794-0.

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Journal articles on the topic 'Optic Remote Sensing'

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