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Sample records for cell-microelectronic sensing technique

  1. A cell-microelectronic sensing technique for profiling cytotoxicity of chemicals.

    PubMed

    Boyd, Jessica M; Huang, Li; Xie, Li; Moe, Birget; Gabos, Stephan; Li, Xing-Fang

    2008-05-12

    A cell-microelectronic sensing technique is developed for profiling chemical cytotoxicity and is used to study different cytotoxic effects of the same class chemicals using nitrosamines as examples. This technique uses three human cell lines (T24 bladder, HepG2 liver, and A549 lung carcinoma cells) and Chinese hamster ovary (CHO-K1) cells in parallel as the living components of the sensors of a real-time cell electronic sensing (RT-CES) method for dynamic monitoring of chemical toxicity. The RT-CES technique measures changes in the impedance of individual microelectronic wells that is correlated linearly with changes in cell numbers during t log phase of cell growth, thus allowing determination of cytotoxicity. Four nitrosamines, N-nitrosodimethylamine (NDMA), N-nitrosodiphenylamine (NDPhA), N-nitrosopiperidine (NPip), and N-nitrosopyrrolidine (NPyr), were examined and unique cytotoxicity profiles were detected for each nitrosamine. In vitro cytotoxicity values (IC(50)) for NDPhA (ranging from 0.6 to 1.9 mM) were significantly lower than the IC(50) values for the well-known carcinogen NDMA (15-95 mM) in all four cell lines. T24 cells were the most sensitive to nitrosamine exposure among the four cell lines tested (T24>CHO>A549>HepG2), suggesting that T24 may serve as a new sensitive model for cytotoxicity screening. Cell staining results confirmed that administration of the IC(50) concentration from the RT-CES experiments inhibited cell growth by 50% compared to the controls, indicating that the RT-CES method provides reliable measures of IC(50). Staining and cell-cycle analysis confirmed that NDPhA caused cell-cycle arrest at the G0/G1 phase, whereas NDMA did not disrupt the cell cycle but induced cell death, thus explaining the different cytotoxicity profiles detected by the RT-CES method. The parallel cytotoxicity profiling of nitrosamines on the four cell lines by the RT-CES method led to the discovery of the unique cytotoxicity of NDPhA causing cell

  2. Remote hydrogen sensing techniques

    NASA Technical Reports Server (NTRS)

    Perry, Cortes L.

    1992-01-01

    The objective of this project is to evaluate remote hydrogen sensing methodologies utilizing metal oxide semi-conductor field effect transistors (MOS-FET) and mass spectrometric (MS) technologies and combinations thereof.

  3. Discriminative sensing techniques

    NASA Astrophysics Data System (ADS)

    Lewis, Keith

    2008-10-01

    The typical human vision system is able to discriminate between a million or so different colours, yet is able to do this with a chromatic sensor array that is fundamentally based on three different receptors, sensitive to light in the blue, green and red portions of the visible spectrum. Some biological organisms have extended capabilities, providing vision in the ultra-violet, whilst others, such as some species of mantis shrimp reportedly have sixteen different types of photo-receptors. In general the biological imaging sensor takes a minimalist approach to sensing its environment, whereas current optical engineering approaches follow a 'brute' force solution where the challenge of hyperspectral imaging is addressed by various schemes for spatial and spectral dispersion of radiation across existing detector arrays. This results in a problem for others to solve in the processing and communication of the generated hypercube of data. This paper explores the parallels between some of those biological systems and the various design concepts being developed for discriminative imaging, drawing on activity supported by the UK Electro-Magnetic Remote Sensing Defence Technology Centre (EMRS DTC).

  4. Remote tire pressure sensing technique

    NASA Technical Reports Server (NTRS)

    Robinson, Howard H. (Inventor); Mcginnis, Timothy A. (Inventor); Daugherty, Robert H. (Inventor)

    1993-01-01

    A remote tire pressure sensing technique is provided which uses vibration frequency to determine tire pressure. A vibration frequency measuring device is attached to the external surface of a tire which is then struck with an object, causing the tire to vibrate. The frequency measuring device measures the vibrations and converts the vibrations into corresponding electrical impulses. The electrical impulses are then fed into the frequency analyzing system which uses the electrical impulses to determine the relative peaks of the vibration frequencies as detected by the frequency measuring device. The measured vibration frequency peaks are then compared to predetermined data describing the location of vibration frequency peaks for a given pressure, thereby determining the air pressure of the tire.

  5. Vision sensing techniques in aeronautics and astronautics

    NASA Technical Reports Server (NTRS)

    Hall, E. L.

    1988-01-01

    The close relationship between sensing and other tasks in orbital space, and the integral role of vision sensing in practical aerospace applications, are illustrated. Typical space mission-vision tasks encompass the docking of space vehicles, the detection of unexpected objects, the diagnosis of spacecraft damage, and the inspection of critical spacecraft components. Attention is presently given to image functions, the 'windowing' of a view, the number of cameras required for inspection tasks, the choice of incoherent or coherent (laser) illumination, three-dimensional-to-two-dimensional model-matching, edge- and region-segmentation techniques, and motion analysis for tracking.

  6. Remote sensing as a mineral prospecting technique

    NASA Technical Reports Server (NTRS)

    Meneses, P. R. (Principal Investigator)

    1984-01-01

    Remote sensing and its application as an alternative technique to mineral resource exploration are reviewed. Emphasis is given here to the analysis of the three basic attributes of remote sensing, i.e., spatial attributes related to regional structural mapping, spectral attributes related to rock discrimination and seasonal attributes related to geobotanic anomalies mapping, all of which are employed in mineral exploration. Special emphasis is given to new developments of the Thematic Mapper of the LANDSAT-5, principally with reference to the application of the bands 1.6 and 2.2 microns to map hydrothermally altered rocks and the band of red and blue shift to geobotanical anomalies mapping.

  7. Introduction to the physics and techniques of remote sensing

    NASA Technical Reports Server (NTRS)

    Elachi, Charles

    1987-01-01

    This book presents a comprehensive overview of the basics behind remote-sensing physics, techniques, and technology. The physics of wave/matter interactions, techniques of remote sensing across the electromagnetic spectrum, and the concepts behind remote sensing techniques now established and future ones under development are discussed. Applications of remote sensing are described for a wide variety of earth and planetary atmosphere and surface sciences. Solid surface sensing across the electromagnetic spectrum, ocean surface sensing, basic principles of atmospheric sensing and radiative transfer, and atmospheric remote sensing in the microwave, millimeter, submillimeter, and infrared regions are examined.

  8. Introduction to the physics and techniques of remote sensing

    NASA Technical Reports Server (NTRS)

    Elachi, Charles

    1987-01-01

    This book presents a comprehensive overview of the basics behind remote-sensing physics, techniques, and technology. The physics of wave/matter interactions, techniques of remote sensing across the electromagnetic spectrum, and the concepts behind remote sensing techniques now established and future ones under development are discussed. Applications of remote sensing are described for a wide variety of earth and planetary atmosphere and surface sciences. Solid surface sensing across the electromagnetic spectrum, ocean surface sensing, basic principles of atmospheric sensing and radiative transfer, and atmospheric remote sensing in the microwave, millimeter, submillimeter, and infrared regions are examined.

  9. Computational intelligence techniques for tactile sensing systems.

    PubMed

    Gastaldo, Paolo; Pinna, Luigi; Seminara, Lucia; Valle, Maurizio; Zunino, Rodolfo

    2014-06-19

    Tactile sensing helps robots interact with humans and objects effectively in real environments. Piezoelectric polymer sensors provide the functional building blocks of the robotic electronic skin, mainly thanks to their flexibility and suitability for detecting dynamic contact events and for recognizing the touch modality. The paper focuses on the ability of tactile sensing systems to support the challenging recognition of certain qualities/modalities of touch. The research applies novel computational intelligence techniques and a tensor-based approach for the classification of touch modalities; its main results consist in providing a procedure to enhance system generalization ability and architecture for multi-class recognition applications. An experimental campaign involving 70 participants using three different modalities in touching the upper surface of the sensor array was conducted, and confirmed the validity of the approach.

  10. Computational Intelligence Techniques for Tactile Sensing Systems

    PubMed Central

    Gastaldo, Paolo; Pinna, Luigi; Seminara, Lucia; Valle, Maurizio; Zunino, Rodolfo

    2014-01-01

    Tactile sensing helps robots interact with humans and objects effectively in real environments. Piezoelectric polymer sensors provide the functional building blocks of the robotic electronic skin, mainly thanks to their flexibility and suitability for detecting dynamic contact events and for recognizing the touch modality. The paper focuses on the ability of tactile sensing systems to support the challenging recognition of certain qualities/modalities of touch. The research applies novel computational intelligence techniques and a tensor-based approach for the classification of touch modalities; its main results consist in providing a procedure to enhance system generalization ability and architecture for multi-class recognition applications. An experimental campaign involving 70 participants using three different modalities in touching the upper surface of the sensor array was conducted, and confirmed the validity of the approach. PMID:24949646

  11. Remote Sensing Techniques for Monitoring Aquatic Vegetation

    NASA Astrophysics Data System (ADS)

    Blanco, Alfonso

    Hydrilla is an important submerged aquatic vegetation because it has a large capacity to absorb pollutants and it is an indicator of the eutrophic status of a waterbody. Monitoring and restoration of submerged aquatic vegetation is key for the preservation and restoration of the Chesapeake Bay. Remote sensing techniques have been used for assessing wetlands and non-invasive aquatic species, but there is limited studies of hydrilla monitoring combined with space-borne, airborne and in-situ remote sensing measurements for detecting and mapping hydrilla infestation. The first objective of this research was to establish a database of hydrilla spectral signatures from an experimental tank and from a field setting using a handheld spectrometer. The spectral signatures collected will be used to identify the optimal spectral and spatial characteristics that are required to identify and classify the distribution of hydrilla canopies in water bodies. The second objective is to process and analyze two hyperspectral images from a space-borne (Hyperion) and airborne (AISA) sensors with ENVI for detecting and mapping the infestation of hydrilla vertillicata in a coastal estuary in Chesapeake Bay. The third objective was to validate the satellite and airborne hyperspectral images with the spectral signatures collected with the in-situ field measurements. In addition, the Hyperion and AISA imaging results were compared with ground surveys and aerial photos collected by the Maryland Department of Natural Resources and the Virginia Institute of Marine Sciences for verifying the extent and the location of the hydrilla canopies. The hyperspectral analysis of both sensors provided for a dual results, one is the identification and classification of hydrilla from hyperspectral imaging sensors and secondly the identification of algae blooms in very productive waters. A hydrilla spectral signature database was established and housed in GMU's EastFIRE Lab of Environmental Science and

  12. Bibliography of Remote Sensing Techniques Used in Wetland Research.

    DTIC Science & Technology

    1993-01-01

    remote sensing technology for detecting changes in wetland environments. This report documents a bibliographic search conducted as part of that work unit on applications of remote sensing techniques in wetland research. Results were used to guide research efforts on the use of remote sensing technology for wetland change detection and assessment. The citations are presented in three appendixes, organized by wetland type, sensor type, and author.... Change detection, Wetland assessment, Remote sensing ,

  13. Wind Predictability and Remote Sensing Techniques,

    DTIC Science & Technology

    The report presents the unclassified findings from the Investigation of Airborne Wind Sensing Systems conducted under AIRTASK A30303/323/70F17311002. Included is a summary of the current accuracy of wind speed and direction forecasts, a list of possible methods for remote sensing meteorological data, a list of areas of application of the given methods and a list of contacts made for information relevant to this evaluation. (Author)

  14. A comparison of force sensing techniques for planetary manipulation

    NASA Technical Reports Server (NTRS)

    Helmick, Daniel; Okon, Avi; DiCicco, Matt

    2006-01-01

    Five techniques for sensing forces with a manipulator are compared analytically and experimentally. The techniques compared are: a six-axis wrist force/torque sensor, joint torque sensors, link strain gauges, motor current sensors, and flexibility modeling. The accuracy and repeatability fo each technique is quantified and compared.

  15. A comparison of force sensing techniques for planetary manipulation

    NASA Technical Reports Server (NTRS)

    Helmick, Daniel; Okon, Avi; DiCicco, Matt

    2006-01-01

    Five techniques for sensing forces with a manipulator are compared analytically and experimentally. The techniques compared are: a six-axis wrist force/torque sensor, joint torque sensors, link strain gauges, motor current sensors, and flexibility modeling. The accuracy and repeatability fo each technique is quantified and compared.

  16. Evaluation of reforestation using remote sensing techniques

    NASA Technical Reports Server (NTRS)

    Parada, N. D. J. (Principal Investigator); Filho, P. H.; Shimabukuro, Y. E.; Dossantos, J. R.

    1982-01-01

    The utilization of remotely sensed orbital data for forestry inventory. The study area (approximately 491,100 ha) encompasses the municipalities of Ribeirao Preto, Altinopolis, Cravinhos, Serra Azul, Luis Antonio, Sao Simao, Sant Rita do Passa Quatro and Santa Rosa do Viterbo (Sao Paulo State). Materials used were LANDSAT data from channels 5 and 7 (scale 1:250,000) and CCT's. Visual interpretation of the imagery showed that for 1977 a total of 37,766.00 ha and for 1979 38,003.75 ha were reforested with Pinus and Eucalyptus within the area under study. The results obtained show that LANDSAT data can be used efficiently in forestry inventory studies.

  17. Layered classification techniques for remote sensing applications

    NASA Technical Reports Server (NTRS)

    Swain, P. H.; Wu, C. L.; Landgrebe, D. A.; Hauska, H.

    1975-01-01

    The single-stage method of pattern classification utilizes all available features in a single test which assigns the unknown to a category according to a specific decision strategy (such as the maximum likelihood strategy). The layered classifier classifies the unknown through a sequence of tests, each of which may be dependent on the outcome of previous tests. Although the layered classifier was originally investigated as a means of improving classification accuracy and efficiency, it was found that in the context of remote sensing data analysis, other advantages also accrue due to many of the special characteristics of both the data and the applications pursued. The layered classifier method and several of the diverse applications of this approach are discussed.

  18. Fluorescence sensing techniques for vegetation assessment.

    PubMed

    Corp, Lawrence A; Middleton, Elizabeth M; McMurtrey, James E; Campbell, Petya K Entcheva; Butcher, L Maryn

    2006-02-10

    Active fluorescence (F) sensing systems have long been suggested as a means to identify species composition and determine physiological status of plants. Passive F systems for large-scale remote assessment of vegetation will undoubtedly rely on solar-induced F (SIF), and this information could potentially be obtained from the Fraunhofer line depth (FLD) principle. However, understanding the relationships between the information and knowledge gained from active and passive systems remains to be addressed. Here we present an approach in which actively induced F spectral data are used to simulate and project the magnitude of SIF that can be expected from near-ground observations within selected solar Fraunhofer line regions. Comparisons among vegetative species and nitrogen (N) supply treatments were made with three F approaches: the passive FLD principle applied to telluric oxygen (O2) bands from field-acquired canopy reflectance spectra, simulated SIF from actively induced laboratory emission spectra of leaves at a series of solar Fraunhofer lines ranging from 422 to 758 nm, and examination of two dual-F excitation algorithms developed from laboratory data. From these analyses we infer that SIF from whole-plant canopies can be simulated by use of laboratory data from active systems on individual leaves and that SIF has application for the large-scale assessment of vegetation.

  19. Offshore winds using remote sensing techniques

    NASA Astrophysics Data System (ADS)

    Peña, Alfredo; Bay Hasager, Charlotte; Gryning, Sven-Erik; Courtney, Michael; Antoniou, Ioannis; Mikkelsen, Torben; Sørensen, Paul

    2007-07-01

    Ground-based remote sensing instruments can observe winds at different levels in the atmosphere where the wind characteristics change with height: the range of heights where modern turbine rotors are operating. A six-month wind assessment campaign has been made with a LiDAR (Light Detection And Ranging) and a SoDAR (Sound Detection and Ranging) on the transformer/platform of the world's largest offshore wind farm located at the West coast of Denmark to evaluate their ability to observe offshore winds. The high homogeneity and low turbulence levels registered allow the comparison of LiDAR and SoDAR with measurements from cups on masts surrounding the wind farm showing good agreement for both the mean wind speed and the longitudinal component of turbulence. An extension of mean wind speed profiles from cup measurements on masts with LiDAR observations results in a good match for the free sectors at different wind speeds. The log-linear profile is fitted to the extended profiles (averaged over all stabilities and roughness lengths) and the deviations are small. Extended profiles of turbulence intensity are also shown for different wind speeds up to 161 m. Friction velocities and roughness lengths calculated from the fitted log-linear profile are compared with the Charnock model which seems to overestimate the sea roughness for the free sectors.

  20. Evaluation of a Temperature Remote Sensing Technique.

    DTIC Science & Technology

    1987-07-01

    concnional Raman for the technique is to monitor temperature in a super- spectroscopy , shich rCqttircs the ncastrement of rela- somio acrod,,namic test...where atomic col- spread of the absorption line. It is normalized such that lisions are infrequent, the Doppler effect determines the width of the...ex- Note: Only the intense modes were recorded cellent tool for high-resolution spectroscopy . at each temperature Coarse frequency tuning of the laser

  1. Monitoring marine pollution by airborne remote sensing techniques

    SciTech Connect

    Yuanfu, S.; Quanan, Z.

    1982-06-01

    In order to monitor marine pollution by airborne remote sensing techniques, some comprehensive test of airborne remote sensing, involving monitoring marine oil pollution, were performed at several bay areas of China. This paper presents some typical results of monitoring marine oil pollution. The features associated with the EM spectrum (visible, thermal infrared, and microwave) response of marine oil spills is briefly analyzed. It has been verified that the airborne oil surveillance systems manifested their advantages for monitoring the oil pollution of bay environments.

  2. Spectral sensing technique for water constituents

    NASA Astrophysics Data System (ADS)

    Zhou, Jing

    Spectral measurements of optical properties of water were conducted throughout the Chesapeake Bay area during the 2005 summer cruise campaign. This included reflectance, absorption, attenuation and backscattering spectra. The analysis of the data illustrates the diversity and complexity of constituents that shape spectral features of the coastal water. A novel technique is proposed to separate the chlorophyll fluorescence component from the reflectance spectra of algae contained water. This approach utilizes of polarization properties of elastically scattered light and the unpolarized nature of fluorescence and was successfully applied to measurements of various algae species first in lab and later in field measurements. The efficiency and limitation of this approach has been further examined under various conditions as well as through vector radiative transfer modeling. Finally Twomey Iterative Method (TIM) has been applied to the retrieval of hydrosol microphysical properties for the first time. Assuming a known refractive index, both single and multi-mode distributions were successfully retrieved from both simulation and experiments through the introduction of an initial distribution biased towards larger particles. In addition, the technique is extended to the retrieval of an unknown refractive index, which is also validated using both simulation and experimental results.

  3. Development of sensing techniques for weaponry health monitoring

    NASA Astrophysics Data System (ADS)

    Edwards, Eugene; Ruffin, Paul B.; Walker, Ebonee A.; Brantley, Christina L.

    2013-04-01

    Due to the costliness of destructive evaluation methods for assessing the aging and shelf-life of missile and rocket components, the identification of nondestructive evaluation methods has become increasingly important to the Army. Verifying that there is a sufficient concentration of stabilizer is a dependable indicator that the missile's double-based solid propellant is viable. The research outlined in this paper summarizes the Army Aviation and Missile Research, Development, and Engineering Center's (AMRDEC's) comparative use of nanoporous membranes, carbon nanotubes, and optical spectroscopic configured sensing techniques for detecting degradation in rocket motor propellant. The first sensing technique utilizes a gas collecting chamber consisting of nanoporous structures that trap the smaller solid propellant particles for measurement by a gas analysis device. In collaboration with NASA-Ames, sensing methods are developed that utilize functionalized single-walled carbon nanotubes as the key sensing element. The optical spectroscopic sensing method is based on a unique light collecting optical fiber system designed to detect the concentration of the propellant stabilizer. Experimental setups, laboratory results, and overall effectiveness of each technique are presented in this paper. Expectations are for the three sensing mechanisms to provide nondestructive evaluation methods that will offer cost-savings and improved weaponry health monitoring.

  4. Transformer insulation monitoring by optical sensing techniques

    NASA Astrophysics Data System (ADS)

    Uttamchandani, Deepak G.; Blue, Robert; Farish, O.

    1998-08-01

    High voltage transformers use paper to insulate the electrical windings present in the core which is then subsequently immersed in oil. In service, the temperature of the windings will increase to typically 80 degrees C. If the transformer is loaded to beyond its design ratings, the temperature can exceed 100 degrees C causing the cellulose chains in the paper to cleave at an accelerated rate, resulting in the degradation of mechanical strength and performance of the insulation. If unchecked, this can lead to catastrophic failure of the transformed and accompanying disruption to electricity supply and large economic losses to the operating utility. Furfuraldehyde (FFA) is a chemical by-product which is released into the oil by the thermal degradation of the paper winding. The concentration of FFA within the oil has been directly related to the condition of the paper insulation. We have developed absorbance and fluorescence optical techniques incorporating a novel FFA- sensitive material which we have invested at our laboratories. This material has been incorporated into a prototype portable optoelectronic instrument for the measurement of FFA at the site of the transformer. Results of experiments will be presented, and the implication of these results for condition monitoring of HV transformer will be discussed.

  5. Millimeter-wave/THz FMCW radar techniques for sensing applications

    NASA Astrophysics Data System (ADS)

    Mirando, D. Amal; Higgins, Michael D.; Wang, Fenggui; Petkie, Douglas T.

    2016-10-01

    Millimeter-wave and terahertz continuous-wave radar systems have been used to measure physiological signatures for biometric applications and for a variety of non-destructive evaluation applications, such as the detection of defects in materials. Sensing strategies for the simplest homodyne systems, such as a Michelson Interferometer, can be enhanced by using Frequency Modulated Continuous Wave (FMCW) techniques. This allows multiple objects or surfaces to be range resolved while monitoring the phase of the signal in a particular range bin. We will discuss the latest developments in several studies aimed at demonstrating how FMCW techniques can enhance mmW/THz sensing applications.

  6. Remote sensing techniques for support of coastal zone resource management.

    NASA Technical Reports Server (NTRS)

    Piland, R. O.

    1973-01-01

    Description of remote sensing studies carried out for the purpose of developing and/or demonstrating techniques which can be employed for land use inventory, marsh vegetation classification, and water characteristics surveys. Attention is given to results obtained with (1) photo interpretation techniques and procedures for the development of land use information from high-altitude aircraft and satellite imagery, (2) computer based pattern recognition techniques utilizing multispectral scanner data for marsh vegetation classification, and (3) infrared and microwave techniques for the monitoring and surveying of coastal water temperature and salinity characteristics.

  7. Application of sensing techniques to cellular force measurement.

    PubMed

    Li, Bin; Wang, James H-C

    2010-01-01

    Cell traction forces (CTFs) are the forces produced by cells and exerted on extracellular matrix or an underlying substrate. CTFs function to maintain cell shape, enable cell migration, and generate and detect mechanical signals. As such, they play a vital role in many fundamental biological processes, including angiogenesis, inflammation, and wound healing. Therefore, a close examination of CTFs can enable better understanding of the cellular and molecular mechanisms of such processes. To this end, various force-sensing techniques for CTF measurement have been developed over the years. This article will provide a concise review of these sensing techniques and comment on the needs for improved force-sensing technologies for cell mechanics and biology research.

  8. Remote sensing techniques aid in preattack planning for fire management

    Treesearch

    Lucy Anne Salazar

    1982-01-01

    Remote sensing techniques were investigated as an alternative for documenting selected prettack fire planning information. Locations of fuel models, road systems, and water sources were recorded by Landsat satellite imagery and aerial photography for a portion of the Six Rivers National Forest in northwestern California. The two fuel model groups used were from the...

  9. Natural resource inventory for urban planning utilizing remote sensing techniques

    NASA Technical Reports Server (NTRS)

    Foster, K. E.; Mackey, P. F.; Bonham, C. D.

    1972-01-01

    Remote sensing techniques were applied to the lower Pantano Wash area to acquire data for planning an ecological balance between the expanding Tucson metropolitan area and its environment. The types and distribution of vegetation are discussed along with the hydrologic aspects of the Wash.

  10. Detection of southern corn leaf blight by remote sensing techniques.

    NASA Technical Reports Server (NTRS)

    Bauer, M. E.; Swain, P. H.; Mroczynski, R. P.; Anuta, P. E.; Macdonald, R. B.

    1971-01-01

    Multispectral photographic and scanner data were collected over western Indiana in August and September 1970, to determine the detectability of southern corn leaf blight by remote sensing. Measurements were made at altitudes of 3000 to 7000 ft. Color, color IR, and multiband black and white photography were collected at altitudes from 3000 to 60,000 ft. Six levels of infection based on the amount of leaf damage were identified in the fields. Three levels of infection were detected with color IR photography by standard photo-interpretive techniques. Up to five levels of infection were distinguished by applying automatic pattern recognition techniques to the multispectral scanner data. The results illustrate the potential of remote sensing techniques in the detection of crop diseases.

  11. Development of carbon fiber-based piezoresistive linear sensing technique

    NASA Astrophysics Data System (ADS)

    Yang, Caiqian; Wu, Zhishen; Huang, Huang

    2009-03-01

    In this paper, the development of carbon fiber-based piezoresistive linear sensing technique and its application in civil engineering structures is studied and summarized. The sensing mechanism is based on the electrical conductivity and piezoresistivity of different types of carbon fibers. Firstly, the influences of values of signal currents and temperature on the sensing properties are studied to decide the suitable sensing current. Then, the linear temperature and strain sensing feasibility of different types of carbon fibers is addressed and discussed. Finally, the application of this kind of sensors is studied in monitoring the health of reinforced concrete (RC) and prestressed concrete (PC) structures. A good linearity of fractional change in electrical resistance (ER) (ΔR/R0)-strain and &DeltaR/R0-temperature is demonstrated. The &DeltaR/R0-strain and &DeltaR/R0-temperature curves of CFRP/HCFRP sensors can be well fitted with a line with a correlation coefficient larger than 0.978. All these reveal that carbon fibers reinforced polymer (CFRP) can be used as both piezoresistive linear strain and temperature sensors.

  12. Molecular biology techniques and applications for ocean sensing

    NASA Astrophysics Data System (ADS)

    Zehr, J. P.; Hewson, I.; Moisander, P.

    2009-05-01

    The study of marine microorganisms using molecular biological techniques is now widespread in the ocean sciences. These techniques target nucleic acids which record the evolutionary history of microbes, and encode for processes which are active in the ocean today. Molecular techniques can form the basis of remote instrumentation sensing technologies for marine microbial diversity and ecological function. Here we review some of the most commonly used molecular biological techniques. These techniques include the polymerase chain reaction (PCR) and reverse-transcriptase PCR, quantitative PCR, whole assemblage "fingerprinting" approaches (based on nucleic acid sequence or length heterogeneity), oligonucleotide microarrays, and high-throughput shotgun sequencing of whole genomes and gene transcripts, which can be used to answer biological, ecological, evolutionary and biogeochemical questions in the ocean sciences. Moreover, molecular biological approaches may be deployed on ocean sensor platforms and hold promise for tracking of organisms or processes of interest in near-real time.

  13. Computational ghost imaging: advanced compressive sensing (CS) technique

    NASA Astrophysics Data System (ADS)

    Katkovnik, Vladimir; Astola, Jaakko

    2012-10-01

    A novel efficient variational technique for speckle imaging is discussed. It is developed with the main motivation to filter noise, to wipe out the typical diffraction artifacts and to achieve crisp imaging. A sparse modeling is used for the wave field at the object plane in order to overcome the loss of information due to the ill-posedness of forward propagation image formation operators. This flexible and data adaptive modeling relies on the recent progress in sparse imaging and compressive sensing (CS). Being in line with the general formalism of CS, we develop an original approach to wave field reconstruction.7 In this paper we demonstrate this technique in its application for computational amplitude ghost imaging (GI), where a spatial light modulator (SLM) is used in order to generate a speckle wave field sensing a transmitted mask object.

  14. Adaptive remote sensing techniques implementing swarms of mobile agents

    NASA Astrophysics Data System (ADS)

    Cameron, Stewart M.; Loubriel, Guillermo M.; Robinett, Rush D., III; Stantz, Keith M.; Trahan, Michael W.; Wagner, John S.

    1999-07-01

    Measurement and signal intelligence of the battlespace has created new requirements in information management, communication and interoperability as they effect surveillance and situational awareness. In many situations, stand-off remote-sensing and hazard-interdiction techniques over realistic operational areas are often impractical and difficult to characterize. An alternative approach is to implement adaptive remote-sensing techniques with swarms of mobile agents employing collective behavior for optimization of mapping signatures and positional orientation (registration). We have expanded intelligent control theory using physics-based collective behavior models and genetic algorithms to produce a uniquely powerful implementation of distributed ground-based measurement incorporating both local collective behavior, and niter-operative global optimization for sensor fusion and mission oversight. By using a layered hierarchical control architecture to orchestrate adaptive reconfiguration of semi-autonomous robotic agents, we can improve overall robustness and functionality in dynamic tactical environments without information bottlenecking.

  15. Remote sensing techniques in cultural resource management archaeology

    NASA Astrophysics Data System (ADS)

    Johnson, Jay K.; Haley, Bryan S.

    2003-04-01

    Cultural resource management archaeology in the United States concerns compliance with legislation set in place to protect archaeological resources from the impact of modern activities. Traditionally, surface collection, shovel testing, test excavation, and mechanical stripping are used in these projects. These methods are expensive, time consuming, and may poorly represent the features within archaeological sites. The use of remote sensing techniques in cultural resource management archaeology may provide an answer to these problems. Near-surface geophysical techniques, including magnetometry, resistivity, electromagnetics, and ground penetrating radar, have proven to be particularly successful at efficiently locating archaeological features. Research has also indicated airborne and satellite remote sensing may hold some promise in the future for large-scale archaeological survey, although this is difficult in many areas of the world where ground cover reflect archaeological features in an indirect manner. A cost simulation of a hypothetical data recovery project on a large complex site in Mississippi is presented to illustrate the potential advantages of remote sensing in a cultural resource management setting. The results indicate these techniques can save a substantial amount of time and money for these projects.

  16. A satellite remote sensing technique for geological structure horizon mapping

    SciTech Connect

    Fraser, A.; Huggins, P.; Rees, J.

    1996-08-01

    A Satellite Remote Sensing Technique is demonstrated for generating near surface geological structure data. This technique enables the screening of large areas and targeting of seismic acquisition during hydrocarbon exploration. This is of particular advantage in terrains where surveying is logistically difficult. Landsat Thematic Mapper (TM) data and a high resolution Digital Elevation Model (DEM), are used to identify and map outcropping horizons. These are used to reconstruct the near surface structure. The technique is applied in Central Yemen which is characterised by a {open_quote}layer-cake{close_quote} geological and low dipping terrain. The results are validated using 2D seismic data. The near surface map images faults and structure not apparent in the raw data. Comparison with the structure map generated from a 2D seismic data indicates very good structural and fault correlation. The near surface map successfully highlights areas of potential closure at reservoir depths.

  17. LIFES: Laser Induced Fluorescence and Environmental Sensing. [remote sensing technique for marine environment

    NASA Technical Reports Server (NTRS)

    Houston, W. R.; Stephenson, D. G.; Measures, R. M.

    1975-01-01

    A laboratory investigation has been conducted to evaluate the detection and identification capabilities of laser induced fluorescence as a remote sensing technique for the marine environment. The relative merits of fluorescence parameters including emission and excitation profiles, intensity and lifetime measurements are discussed in relation to the identification of specific targets of the marine environment including crude oils, refined petroleum products, fish oils and algae. Temporal profiles displaying the variation of lifetime with emission wavelength have proven to add a new dimension of specificity and simplicity to the technique.

  18. LIFES: Laser Induced Fluorescence and Environmental Sensing. [remote sensing technique for marine environment

    NASA Technical Reports Server (NTRS)

    Houston, W. R.; Stephenson, D. G.; Measures, R. M.

    1975-01-01

    A laboratory investigation has been conducted to evaluate the detection and identification capabilities of laser induced fluorescence as a remote sensing technique for the marine environment. The relative merits of fluorescence parameters including emission and excitation profiles, intensity and lifetime measurements are discussed in relation to the identification of specific targets of the marine environment including crude oils, refined petroleum products, fish oils and algae. Temporal profiles displaying the variation of lifetime with emission wavelength have proven to add a new dimension of specificity and simplicity to the technique.

  19. Magnetic sensing techniques for humanitarian ordnance detection and discrimination

    NASA Astrophysics Data System (ADS)

    Keranen, Joe; Billings, Steve; Schultz, Gregory; Miller, Jonathan

    2011-06-01

    Detection and discrimination of unexploded ordnance (UXO) in areas of prior conflict is of high importance to the international community and the United States government. For humanitarian applications, sensors and processing methods need to be robust, reliable, and easy to train and implement using indigenous UXO removal personnel. This paper focuses on magnetometer sensing techniques, processing, and operation for UXO detection and discrimination applications. Specifically, we discuss the collection, processing, and discrimination of data collected using the PACMAG man-portable system consisting of arrays of sensitive total-field magnetometers, global positioning (GPS) combined with digital odometers, and a data acquisition system. We outline preliminary standard operating procedures for optimal collection of UXO-induced magnetic fields and associated position data using either a GPS, or odometer when surveying in GPS-denied areas. Processing techniques such as gridding and filtering, target picking, and discrimination lead to estimates of target size and location. Emphasis is placed on simplifying the production of magnetometer hardware and software for use by minimally-trained personnel with no advanced knowledge of magnetic sensing and geophysics.

  20. Compressed Sensing Techniques Applied to Ultrasonic Imaging of Cargo Containers.

    PubMed

    López, Yuri Álvarez; Lorenzo, José Ángel Martínez

    2017-01-15

    One of the key issues in the fight against the smuggling of goods has been the development of scanners for cargo inspection. X-ray-based radiographic system scanners are the most developed sensing modality. However, they are costly and use bulky sources that emit hazardous, ionizing radiation. Aiming to improve the probability of threat detection, an ultrasonic-based technique, capable of detecting the footprint of metallic containers or compartments concealed within the metallic structure of the inspected cargo, has been proposed. The system consists of an array of acoustic transceivers that is attached to the metallic structure-under-inspection, creating a guided acoustic Lamb wave. Reflections due to discontinuities are detected in the images, provided by an imaging algorithm. Taking into consideration that the majority of those images are sparse, this contribution analyzes the application of Compressed Sensing (CS) techniques in order to reduce the amount of measurements needed, thus achieving faster scanning, without compromising the detection capabilities of the system. A parametric study of the image quality, as a function of the samples needed in spatial and frequency domains, is presented, as well as the dependence on the sampling pattern. For this purpose, realistic cargo inspection scenarios have been simulated.

  1. Water quality assessment in Kelantan delta using remote sensing technique

    NASA Astrophysics Data System (ADS)

    Syahreza, S.; MatJafri, M. Z.; Lim, H. S.; Mustapha, M. R.

    2012-09-01

    This paper presents the utilities of remote sensing technique for water quality assessment in Kelantan Delta, Malaysia. Remote sensing is one of the effective methods for water quality monitoring through image analysis of study area. Spectral reflectance signatures of Kelantan Delta were measured from 20 stations using ASD Handheld spectroradiometer from regions with different turbidity level. Water samples collected from these stations were taken to the laboratory for measure turbidity in Nephelometric Turbidity Unit (NTU). The objective of this study is to examine the potential of ALOS on Japanese Earth Observing Satellite (JEOS) for assessing water quality in Kelantan Delta. There is a large correlation between NTU and the in-situ reflectance at 500 - 620 nm (maximum spectra band between 300 and 1100 nm) is shown by multiple linier regression model, resulting from increasing of turbidity levels, was developed and applied to ALOS band 2 and band 3 (0.42-069 nm). A simple atmospheric correction, based on darkest pixel technique was performed in this study. The ALOS data provides accurate estimates of the mean water quality (R2 = 0.95 and RMSE = 2.26 NTU). The result acquired is reliable to estimate of water quality values for the Kelantan Delta and its implication for future operation.

  2. Recent progress in bio-sensing techniques with encapsulated enzymes.

    PubMed

    Park, Byung-Wook; Yoon, Do-Young; Kim, Dong-Shik

    2010-09-15

    Biosensors with encapsulated enzymes have advantages of high substrate selectivity and sustained enzyme activity. Enzymes are encapsulated in various materials, such as liposome, polymer, and sol-gel or hydro-gel, depending on sensing conditions. By stabilizing the enzymes via encapsulation with new methods and materials the enzyme activity may be maintained for a longer time, and even the selectivity can possibly be enhanced. In general increased mass transfer limitation seems to be the major challenge to investigate more. Novel materials, encapsulation techniques, and sensing mechanisms have been studied intensively for encapsulated enzyme biosensors. In this review, we focus on the recent progress in encapsulated enzyme biosensors published in peer-reviewed journals over the last 10 years. The articles are categorized and reviewed in four groups based on encapsulation techniques incorporating with liposome, polymer, sol-gel or hydro-gel, and peptide. Research articles that are considered critical and noticeable are selected and compared according to these categorizations. Based on these article analyses, we suggested future direction in the encapsulated enzyme biosensor research.

  3. Compressed Sensing Techniques Applied to Ultrasonic Imaging of Cargo Containers

    PubMed Central

    Álvarez López, Yuri; Martínez Lorenzo, José Ángel

    2017-01-01

    One of the key issues in the fight against the smuggling of goods has been the development of scanners for cargo inspection. X-ray-based radiographic system scanners are the most developed sensing modality. However, they are costly and use bulky sources that emit hazardous, ionizing radiation. Aiming to improve the probability of threat detection, an ultrasonic-based technique, capable of detecting the footprint of metallic containers or compartments concealed within the metallic structure of the inspected cargo, has been proposed. The system consists of an array of acoustic transceivers that is attached to the metallic structure-under-inspection, creating a guided acoustic Lamb wave. Reflections due to discontinuities are detected in the images, provided by an imaging algorithm. Taking into consideration that the majority of those images are sparse, this contribution analyzes the application of Compressed Sensing (CS) techniques in order to reduce the amount of measurements needed, thus achieving faster scanning, without compromising the detection capabilities of the system. A parametric study of the image quality, as a function of the samples needed in spatial and frequency domains, is presented, as well as the dependence on the sampling pattern. For this purpose, realistic cargo inspection scenarios have been simulated. PMID:28098841

  4. An integrated sensing technique for smart monitoring of water pipelines

    NASA Astrophysics Data System (ADS)

    Bernini, Romeo; Catapano, Ilaria; Soldovieri, Francesco; Crocco, Lorenzo

    2014-05-01

    Lowering the rate of water leakage from the network of underground pipes is one of the requirements that "smart" cities have to comply with. In fact, losses in the water supply infrastructure have a remarkable social, environmental and economic impact, which obviously conflicts with the expected efficiency and sustainability of a smart city. As a consequence, there is a huge interest in developing prevention policies based on state-of-art sensing techniques and possibly their integration, as well as in envisaging ad hoc technical solutions designed for the application at hand. As a contribution to this framework, in this communication we present an approach aimed to pursue a thorough non-invasive monitoring of water pipelines, with both high spatial and temporal resolution. This goal is necessary to guarantee that maintenance operations are performed timely, so to reduce the extent of the leakage and its possible side effects, and precisely, so to minimize the cost and the discomfort resulting from operating on the water supply network. The proposed approach integrates two sensing techniques that work at different spatial and temporal scales. The first one is meant to provide a continuous (in both space and time) monitoring of the pipeline and exploits a distributed optic fiber sensor based on the Brillouin scattering phenomenon. This technique provides the "low" spatial resolution information (at meter scale) needed to reveal the presence of a leak and call for interventions [1]. The second technique is based on the use of Ground Penetrating Radar (GPR) and is meant to provide detailed images of area where the damage has been detected. GPR systems equipped with suitable data processing strategies [2,3] are indeed capable of providing images of the shallow underground, where the pipes would be buried, characterized by a spatial resolution in the order of a few centimeters. This capability is crucial to address in the most proper way maintenance operations, by for

  5. A practical CO2 flux remote sensing technique

    NASA Astrophysics Data System (ADS)

    Queisser, Manuel; Burton, Mike

    2017-04-01

    An accurate quantification of CO2 flux from both natural and anthropogenic sources is of great interest in various areas of the Earth, environmental and atmospheric sciences. As emitted excess CO2 quickly dilutes into the 400 ppm ambient CO2 concentration and degassing often occurs diffusively, measuring CO2 fluxes is challenging. Therefore, fluxes are usually derived from grids of in-situ measurements, which are labour intensive measurements. Other than a safe measurement distance, remote sensing offers quick, spatially integrated and thus a more thorough measurement of gas fluxes. Active remote sensing combines these merits with operation independent of sunlight or clear sky conditions. Due to their weight and size, active remote sensing platforms for CO2, such as LIDAR, cannot easily be applied in the field or transported overseas. Moreover, their complexity requires a rather lengthy setup procedure to be undertaken by skilled personal. To meet the need for a rugged, practical CO2 remote sensing technique to scan volcanic plumes, we have developed the CO2 LIDAR. It measures 1-D column densities of CO2 with sufficient sensitivity to reveal the contribution of magmatic CO2. The CO2 LIDAR has been mounted inside a small aircraft and used to measure atmospheric column CO2 concentrations between the aircraft and the ground. It was further employed on the ground, measuring CO2 emissions from mud volcanism. During the measurement campaign the CO2 LIDAR demonstrated reliability, portability, quick set-up time (10 to 15 min) and platform independence. This new technique opens the possibility of rapid, comprehensive surveys of point source, open-vent CO2 emissions, as well as emissions from more diffuse sources such as lakes and fumarole fields. Currently, within the proof-of-concept ERC project CarbSens, a further reduction in size, weight and operational complexity is underway with the goal to commercialize the platform. Areas of potential applications include fugitive

  6. Tunnel-Site Selection by Remote Sensing Techniques

    DTIC Science & Technology

    A study of the role of remote sensing for geologic reconnaissance for tunnel-site selection was commenced. For this study, remote sensing was defined...conventional remote sensing . Future research directions are suggested, and the extension of remote sensing to include airborne passive microwave

  7. Integration of geological remote-sensing techniques in subsurface analysis

    USGS Publications Warehouse

    Taranik, James V.; Trautwein, Charles M.

    1976-01-01

    Geological remote sensing is defined as the study of the Earth utilizing electromagnetic radiation which is either reflected or emitted from its surface in wavelengths ranging from 0.3 micrometre to 3 metres. The natural surface of the Earth is composed of a diversified combination of surface cover types, and geologists must understand the characteristics of surface cover types to successfully evaluate remotely-sensed data. In some areas landscape surface cover changes throughout the year, and analysis of imagery acquired at different times of year can yield additional geological information. Integration of different scales of analysis allows landscape features to be effectively interpreted. Interpretation of the static elements displayed on imagery is referred to as an image interpretation. Image interpretation is dependent upon: (1) the geologist's understanding of the fundamental aspects of image formation, and (2.) his ability to detect, delineate, and classify image radiometric data; recognize radiometric patterns; and identify landscape surface characteristics as expressed on imagery. A geologic interpretation integrates surface characteristics of the landscape with subsurface geologic relationships. Development of a geologic interpretation from imagery is dependent upon: (1) the geologist's ability to interpret geomorphic processes from their static surface expression as landscape characteristics on imagery, (2) his ability to conceptualize the dynamic processes responsible for the evolution 6f interpreted geologic relationships (his ability to develop geologic models). The integration of geologic remote-sensing techniques in subsurface analysis is illustrated by development of an exploration model for ground water in the Tucson area of Arizona, and by the development of an exploration model for mineralization in southwest Idaho.

  8. Estimation of Insulator Contaminations by Means of Remote Sensing Technique

    NASA Astrophysics Data System (ADS)

    Han, Ge; Gong, Wei; Cui, Xiaohui; Zhang, Miao; Chen, Jun

    2016-06-01

    The accurate estimation of deposits adhering on insulators is critical to prevent pollution flashovers which cause huge costs worldwide. The traditional evaluation method of insulator contaminations (IC) is based sparse manual in-situ measurements, resulting in insufficient spatial representativeness and poor timeliness. Filling that gap, we proposed a novel evaluation framework of IC based on remote sensing and data mining. Varieties of products derived from satellite data, such as aerosol optical depth (AOD), digital elevation model (DEM), land use and land cover and normalized difference vegetation index were obtained to estimate the severity of IC along with the necessary field investigation inventory (pollution sources, ambient atmosphere and meteorological data). Rough set theory was utilized to minimize input sets under the prerequisite that the resultant set is equivalent to the full sets in terms of the decision ability to distinguish severity levels of IC. We found that AOD, the strength of pollution source and the precipitation are the top 3 decisive factors to estimate insulator contaminations. On that basis, different classification algorithm such as mahalanobis minimum distance, support vector machine (SVM) and maximum likelihood method were utilized to estimate severity levels of IC. 10-fold cross-validation was carried out to evaluate the performances of different methods. SVM yielded the best overall accuracy among three algorithms. An overall accuracy of more than 70% was witnessed, suggesting a promising application of remote sensing in power maintenance. To our knowledge, this is the first trial to introduce remote sensing and relevant data analysis technique into the estimation of electrical insulator contaminations.

  9. Remote sensing techniques applied to seismic vulnerability assessment

    NASA Astrophysics Data System (ADS)

    Juan Arranz, Jose; Torres, Yolanda; Hahgi, Azade; Gaspar-Escribano, Jorge

    2016-04-01

    Advances in remote sensing and photogrammetry techniques have increased the degree of accuracy and resolution in the record of the earth's surface. This has expanded the range of possible applications of these data. In this research, we have used these data to document the construction characteristics of the urban environment of Lorca, Spain. An exposure database has been created with the gathered information to be used in seismic vulnerability assessment. To this end, we have used data from photogrammetric flights at different periods, using both orthorectified images in the visible and infrared spectrum. Furthermore, the analysis is completed using LiDAR data. From the combination of these data, it has been possible to delineate the building footprints and characterize the constructions with attributes such as the approximate date of construction, area, type of roof and even building materials. To carry out the calculation, we have developed different algorithms to compare images from different times, segment images, classify LiDAR data, and use the infrared data in order to remove vegetation or to compute roof surfaces with height value, tilt and spectral fingerprint. In addition, the accuracy of our results has been validated with ground truth data. Keywords: LiDAR, remote sensing, seismic vulnerability, Lorca

  10. Multivariate image processing technique for noninvasive glucose sensing

    NASA Astrophysics Data System (ADS)

    Webb, Anthony J.; Cameron, Brent D.

    2010-02-01

    A potential noninvasive glucose sensing technique was investigated for application towards in vivo glucose monitoring for individuals afflicted with diabetes mellitus. Three dimensional ray tracing simulations using a realistic iris pattern integrated into an advanced human eye model are reported for physiological glucose concentrations ranging between 0 to 500 mg/dL. The anterior chamber of the human eye contains a clear fluid known as the aqueous humor. The optical refractive index of the aqueous humor varies on the order of 1.5x10-4 for a change in glucose concentration of 100 mg/dL. The simulation data was analyzed with a developed multivariate chemometrics procedure that utilizes iris-based images to form a calibration model. Results from these simulations show considerable potential for use of the developed method in the prediction of glucose. For further demonstration, an in vitro eye model was developed to validate the computer based modeling technique. In these experiments, a realistic iris pattern was placed in an analog eye model in which the glucose concentration within the fluid representing the aqueous humor was varied. A series of high resolution digital images were acquired using an optical imaging system. These images were then used to form an in vitro calibration model utilizing the same multivariate chemometric technique demonstrated in the 3-D optical simulations. In general, the developed method exhibits considerable applicability towards its use as an in vivo platform for the noninvasive monitoring of physiological glucose concentration.

  11. Radial velocity data analysis with compressed sensing techniques

    NASA Astrophysics Data System (ADS)

    Hara, Nathan C.; Boué, G.; Laskar, J.; Correia, A. C. M.

    2017-01-01

    We present a novel approach for analysing radial velocity data that combines two features: all the planets are searched at once and the algorithm is fast. This is achieved by utilizing compressed sensing techniques, which are modified to be compatible with the Gaussian process framework. The resulting tool can be used like a Lomb-Scargle periodogram and has the same aspect but with much fewer peaks due to aliasing. The method is applied to five systems with published radial velocity data sets: HD 69830, HD 10180, 55 Cnc, GJ 876 and a simulated very active star. The results are fully compatible with previous analysis, though obtained more straightforwardly. We further show that 55 Cnc e and f could have been respectively detected and suspected in early measurements from the Lick Observatory and Hobby-Eberly Telescope available in 2004, and that frequencies due to dynamical interactions in GJ 876 can be seen.

  12. Advanced Doppler radar physiological sensing technique for drone detection

    NASA Astrophysics Data System (ADS)

    Yoon, Ji Hwan; Xu, Hao; Garcia Carrillo, Luis R.

    2017-05-01

    A 24 GHz medium-range human detecting sensor, using the Doppler Radar Physiological Sensing (DRPS) technique, which can also detect unmanned aerial vehicles (UAVs or drones), is currently under development for potential rescue and anti-drone applications. DRPS systems are specifically designed to remotely monitor small movements of non-metallic human tissues such as cardiopulmonary activity and respiration. Once optimized, the unique capabilities of DRPS could be used to detect UAVs. Initial measurements have shown that DRPS technology is able to detect moving and stationary humans, as well as largely non-metallic multi-rotor drone helicopters. Further data processing will incorporate pattern recognition to detect multiple signatures (motor vibration and hovering patterns) of UAVs.

  13. Remote sensing image denoising by using discrete multiwavelet transform techniques

    NASA Astrophysics Data System (ADS)

    Wang, Haihui; Wang, Jun; Zhang, Jian

    2006-01-01

    We present a new method by using GHM discrete multiwavelet transform in image denoising on this paper. The developments in wavelet theory have given rise to the wavelet thresholding method, for extracting a signal from noisy data. The method of signal denoising via wavelet thresholding was popularized. Multiwavelets have recently been introduced and they offer simultaneous orthogonality, symmetry and short support. This property makes multiwavelets more suitable for various image processing applications, especially denoising. It is based on thresholding of multiwavelet coefficients arising from the standard scalar orthogonal wavelet transform. It takes into account the covariance structure of the transform. Denoising of images via thresholding of the multiwavelet coefficients result from preprocessing and the discrete multiwavelet transform can be carried out by treating the output in this paper. The form of the threshold is carefully formulated and is the key to the excellent results obtained in the extensive numerical simulations of image denoising. We apply the multiwavelet-based to remote sensing image denoising. Multiwavelet transform technique is rather a new method, and it has a big advantage over the other techniques that it less distorts spectral characteristics of the image denoising. The experimental results show that multiwavelet based image denoising schemes outperform wavelet based method both subjectively and objectively.

  14. River flow forecasting in mountainous areas using remote sensing techniques

    NASA Astrophysics Data System (ADS)

    Ikweiri, Fathi Saleh

    The objective of this research is to develop a simple semi-distributed, physically based hydrologic model (SDPB_HM) for mountainous watershed areas. Most of the required watershed parameters in this developed model were acquired using remotely sensed imagery and digital terrain data. A modified technique to involve the use of the land cover properties in the Morton (1983) evapotranspiration model was proposed in this research. This new modified technique was proposed to overcome one of the major disadvantages of the Morton's evapotranspiration model for not having any allowances for the properties of different land cover types (Kite, 1997). The suitability of estimation the evapotranspiration using this modified technique was judged in this research by comparing its results with other average daily evapotranspiration data for an adjacent basin; Cross River Basin in the Rocky Mountain in British Columbia, Canada during year 1987. A new modified procedure for estimating maximum storage capacity in a basin that could estimate the retained rain or snowmelt water within the watershed area related to sink pixels on DTED was presented in this research. A simplified procedure for performing the geometric correction to satellite images based on the Oguro et al. (2001) technique that is used to register these images by utilizing a simulated shaded DTED overlaid with simulated streamlines network image was proposed in this work. A complete three-stage computer classifier (EBPANN) was built in this research that was aimed at minimizing the negative affect of overlapping spectral signatures. This developed computer classifier model was written in C computer program language and utilized in its procedures the error back-propagation neural network this proposed classifier technique was applied to classify a large part from Kananaskis Country area in the Rocky Mountains, Alberta, Canada. An enhanced method was employed in this work for dividing the watershed areas. This new

  15. Close-Range Sensing Techniques in Alpine Terrain

    NASA Astrophysics Data System (ADS)

    Rutzinger, M.; Höfle, B.; Lindenbergh, R.; Oude Elberink, S.; Pirotti, F.; Sailer, R.; Scaioni, M.; Stötter, J.; Wujanz, D.

    2016-06-01

    Early career researchers such as PhD students are a main driving force of scientific research and are for a large part responsible for research innovation. They work on specialized topics within focused research groups that have a limited number of members, but might also have limited capacity in terms of lab equipment. This poses a serious challenge for educating such students as it is difficult to group a sufficient number of them to enable efficient knowledge transfer. To overcome this problem, the Innsbruck Summer School of Alpine Research 2015 on close-range sensing techniques in Alpine terrain was organized in Obergurgl, Austria, by an international team from several universities and research centres. Of the applicants a group of 40 early career researchers were selected with interest in about ten types of specialized surveying tools, i.e. laser scanners, a remotely piloted aircraft system, a thermal camera, a backpack mobile mapping system and different grade photogrammetric equipment. During the one-week summer school, students were grouped according to their personal preference to work with one such type of equipment under guidance of an expert lecturer. All students were required to capture and process field data on a mountain-related theme like landslides or rock glaciers. The work on the assignments lasted the whole week but was interspersed with lectures on selected topics by invited experts. The final task of the summer school participants was to present and defend their results to their peers, lecturers and other colleagues in a symposium-like setting. Here we present the framework and content of this summer school which brought together scientists from close-range sensing and environmental and geosciences.

  16. Remote sensing techniques for vegetation moisture and fire risk estimation

    NASA Astrophysics Data System (ADS)

    Dasgupta, Swarvanu

    This dissertation is aimed at evaluating and improving remote sensing techniques for vegetation moisture and fire risk estimation. Empirical retrievals of vegetation moisture using liquid water absorption based spectral indices such as the NDWI (Normalized Difference Water Index) and NDII (Normalized Difference Infrared Index) may have uncertainties, since these indices cannot fully normalize the reflectance variability due to other biophysical, biochemical, soil and illumination viewing geometry factors. Coupled leaf-canopy reflectance models, National Fire Danger Rating System data and the FARSITE fire behavior model were used to estimate the effect of Live Fuel Moisture Content (LFMC) retrieval uncertainties on fire spread rate predictions. The uncertainty estimation was focused on the Okefenokee National Wildlife Refuge where errors in LFMC retrievals using NDWI and NDII were shown to result in considerable fire spread rate prediction errors at lower LFMC levels. Soil reflectance contamination driven by soil moisture variability was identified as a problem causing errors in Vegetation Water Content (VWC) retrievals over low vegetation conditions. Analysis of canopy reflectance simulations from coupled soil-leaf-canopy reflectance models revealed that VWC isolines were curved and did not converge at the origin of the 1.64mum--0.86mum space. These were identified as causes for the soil moisture contamination of the spectral index NDII. As an improvement strategy an origin transformed NDII, called the SANDII (Soil Adjusted NDII) was designed to minimize soil contamination. Further separate regression models between VWC and the SANDII for different soil moisture classes were proposed to account for the curved nature of VWC isolines. The new technique which requires categorical soil moisture information was shown to reduce VWC estimation errors by about 20% over grassland conditions. The approach was supported using data collected over pastures during the Soil

  17. Polarization mode beating techniques for high-sensitivity intracavity sensing

    NASA Astrophysics Data System (ADS)

    Rosales-Garcia, Andrea

    high finesse and resolution of the system. Experimental changes in the refractive index of air as a function of pressure are in good agreement with theoretical predictions. An alternative fiber laser configuration, which incorporates non-reciprocal elements, allows measuring the optical activity of enantiomeric mixtures using PMB techniques. The sensitivity attained through PMB techniques demonstrates a potential method for ultra-sensitive biochemical sensing and explosive detection.

  18. Hyperspectral remote sensing techniques for early detection of plant diseases

    NASA Astrophysics Data System (ADS)

    Krezhova, Dora; Maneva, Svetla; Zdravev, Tomas

    Hyperspectral remote sensing is an emerging, multidisciplinary field with diverse applications in Earth observation. Nowadays spectral remote sensing techniques allow presymptomatic monitoring of changes in the physiological state of plants with high spectral resolution. Hyperspectral leaf reflectance and chlorophyll fluorescence proved to be highly suitable for identification of growth anomalies of cultural plants that result from the environmental changes and different stress factors. Hyperspectral technologies can find place in many scientific areas, as well as for monitoring of plants status and functioning to help in making timely management decisions. This research aimed to detect a presence of viral infection in young pepper plants (Capsicum annuum L.) caused by Cucumber Mosaic Virus (CMV) by using hyperspectral reflectance and fluorescence data and to assess the effect of some growth regulators on the development of the disease. In Bulgaria CMV is one of the widest spread pathogens, causing the biggest economical losses in crop vegetable production. Leaf spectral reflectance and fluorescence data were collected by a portable fibre-optics spectrometer in the spectral ranges 450÷850 nm and 600-900 nm. Greenhouse experiment with pepper plants of two cultivars, Sivria (sensitive to CMV) and Ostrion (resistant to CMV) were used. The plants were divided into six groups. The first group consisted of healthy (control) plants. At growth stage 4-6 expanded leaf, the second group was inoculated with CMV. The other four groups were treated with growth regulators: Spermine, MEIA (beta-monomethyl ester of itaconic acid), ВТН (benzo(1,2,3)thiadiazole-7-carbothioic acid-S-methyl ester) and Phytoxin. On the next day, the pepper plants of these four groups were inoculated with CMV. The viral concentrations in the plants were determined by the serological method DAS-ELISA. Statistical, first derivative and cluster analysis were applied and several vegetation indices were

  19. Basalt nuclear-waste repository remote sensing using electromagnetic techniques

    SciTech Connect

    Daily, W.D.; Buettner, H.M.

    1984-01-01

    The electromagnetic permittivity and attenuation rate of basalt, from the Near Surface Test Facility of the Basalt Waste Isolation Project at Hanford, Washington, have been measured in the laboratory as a function of water content at frequencies from 25 MHz to 1000 MHz. Both the permittivity and the attenuation rate are strongly related to water content of basalt in this frequency range. Completely dehydrated, the rock has a frequency-independent relative permittivity of about 8 and attenuation rates (inverse skin depths) of 0.04 m/sup -1/ and 3.2 m/sup -1/ at 25 MHz and 1000 MHz, respectively. When completely saturated by tap water to 6% by volume, the relative permittivity ranges from 16.5 to 10.0 and the attenuation ranges from 0.3 m/sup -1/ to 5.5 m/sup -1/ between 25 MHz and 1000 MHz. The data indicate that high-frequency electromagnetic remote sensing techniques, such as those used in radar, cross-borehole tomography, and borehole logging, may be useful in characterizing proposed basalt repositories and monitoring established waste repositories. Electromagnetic methods are particularly suited to delineating water content of the rock and, when completely saturated, crack and pore porosity of the rock mass within a repository. 7 references, 3 figures.

  20. Water Vapor Remote Sensing Techniques: Radiometry and Solar Spectrometry

    NASA Astrophysics Data System (ADS)

    Somieski, A.; Buerki, B.; Cocard, M.; Geiger, A.; Kahle, H.-G.

    The high variability of atmospheric water vapor content plays an important role in space geodesy, climatology and meteorology. Water vapor has a strong influence on transatmospheric satellite signals, the Earth's climate and thus the weather forecasting. Several remote sensing techniques have been developed for the determination of inte- grated precipitable water vapor (IPWV). The Geodesy and Geodynamics Lab (GGL) utilizes the methods of Water Vapor Radiometry and Solar Spectrometry to quantify the amount of tropospheric water vapor and its temporal variations. The Water Vapor Radiometer (WVR) measures the radiation intensity of the atmosphere in a frequency band ranging from 20 to 32 GHz. The Solar Atmospheric MOnitoring Spectrome- ter (SAMOS) of GGL is designed for high-resolution measurements of water vapor absorption lines using solar radiation. In the framework of the ESCOMPTE (ExpÊrience sur Site pour COntraindre les Mod- Éles de Pollution atmosphÊrique et de Transport d'Emissions) field campaign these instruments have been operated near Marseille in 2001. They have aquired a long time series of integrated precipitable water vapor content (IPWV). The accuracy of IPWV measured by WVR and SAMOS is 1 kg/m2. Furthermore meteorological data from radiosondes were used to calculate the IPWV in order to provide comparisons with the results of WVR and SAMOS. The methods of Water Vapor Radiometry and So- lar Spectrometry will be discussed and first preliminary results retrieved from WVR, SAMOS and radiosondes during the ESCOMPTE field campaign will be presented.

  1. Estimation of ambient BVOC emissions using remote sensing techniques

    NASA Astrophysics Data System (ADS)

    Nichol, Janet; Wong, Man Sing

    2011-06-01

    The contribution of Biogenic Volatile Organic Compounds (BVOCs) to local air quality modelling is often ignored due to the difficulty of obtaining accurate spatial estimates of emissions. Yet their role in the formation of secondary aerosols and photochemical smog is thought to be significant, especially in hot tropical cities such as Hong Kong, which are situated downwind from dense forests. This paper evaluates Guenther et al.'s [Guenther, A., Hewitt, C.N., Erickson, D., Fall, R., Geron, C., Graedel, T.E., Harley, P., Klinger, L., Lerdau, M., McKay, W.A., Pierce, T., Scholes, B., Steinbrecher, R., Tallamraju, R., Taylor, J., Zimmerman, P., 1995. A global model of natural volatile organic compound emissions. Journal of Geophysical Research 100, 8873-8892] global model of BVOC emissions, for application at a spatially detailed level to Hong Kong's tropical forested landscape using high resolution remote sensing and ground data. The emission estimates are based on a landscape approach which assigns emission rates directly to ecosystem types not to individual species, since unlike in temperate regions where one or two single species may dominate over large regions, Hong Kong's vegetation is extremely diverse with up to 300 different species in one hectare. The resulting BVOC emission maps are suitable for direct input to regional and local air quality models giving 10 m raster output on an hourly basis over the whole of the Hong Kong territory, an area of 1100 km 2. Due to the spatially detailed mapping of isoprene emissions over the study area, it was possible to validate the model output using field data collected at a precise time and place by replicating those conditions in the model. The field measurement of emissions used for validating the model was based on a canister sampling technique, undertaken under different climatic conditions for Hong Kong's main ecosystem types in both urban and rural areas. The model-derived BVOC flux distributions appeared to be

  2. Reflectance spectroscopy: quantitative analysis techniques for remote sensing applications.

    USGS Publications Warehouse

    Clark, R.N.; Roush, T.L.

    1984-01-01

    Several methods for the analysis of remotely sensed reflectance data are compared, including empirical methods and scattering theories, both of which are important for solving remote sensing problems. The concept of the photon mean path length and the implications for use in modeling reflectance spectra are presented.-from Authors

  3. Integration of remote sensing and geophysical techniques for coastal monitoring

    NASA Astrophysics Data System (ADS)

    Simoniello, T.; Carone, M. T.; Loperte, A.; Satriani, A.; Imbrenda, V.; D'Emilio, M.; Guariglia, A.

    2009-04-01

    Coastal areas are of great environmental, economic, social, cultural and recreational relevance; therefore, the implementation of suitable monitoring and protection actions is fundamental for their preservation and for assuring future use of this resource. Such actions have to be based on an ecosystem perspective for preserving coastal environment integrity and functioning and for planning sustainable resource management of both the marine and terrestrial components (ICZM-EU initiative). We implemented an integrated study based on remote sensing and geophysical techniques for monitoring a coastal area located along the Ionian side of Basilicata region (Southern Italy). This area, between the Bradano and Basento river mouths, is mainly characterized by a narrow shore (10-30 m) of fine sandy formations and by a pine forest planted in the first decade of 50's in order to preserve the coast and the inland cultivated areas. Due to drought and fire events and saltwater intrusion phenomena, such a forest is affected by a strong decline with consequent environmental problems. Multispectral satellite data were adopted for evaluating the spatio-temporal features of coastal vegetation and the structure of forested patterns. The increase or decrease in vegetation activity was analyzed from trends estimated on a time series of NDVI (Normalized Difference Vegetation Index) maps. The fragmentation/connection levels of vegetated patterns was assessed form a set of landscape ecology metrics elaborated at different structure scales (patch, class and landscape) on satellite cover classifications. Information on shoreline changes were derived form a multi-source data set (satellite data, field-GPS surveys and Aerial Laser Scanner acquisitions) by taking also into account tidal effects. Geophysical campaigns were performed for characterizing soil features and limits of salty water infiltrations. Form vertical resistivity soundings (VES), soil resistivity maps at different a deeps (0

  4. Adaptive Remote-Sensing Techniques Implementing Swarms of Mobile Agents

    SciTech Connect

    Asher, R.B.; Cameron, S.M.; Loubriel, G.M.; Robinett, R.D.; Stantz, K.M.; Trahan, M.W.; Wagner, J.S.

    1998-11-25

    In many situations, stand-off remote-sensing and hazard-interdiction techniques over realistic operational areas are often impractical "and difficult to characterize. An alternative approach is to implement an adap- tively deployable array of sensitive agent-specific devices. Our group has been studying the collective be- havior of an autonomous, multi-agent system applied to chedbio detection and related emerging threat applications, The current physics-based models we are using coordinate a sensor array for mukivanate sig- nal optimization and coverage as re,alized by a swarm of robots or mobile vehicles. These intelligent control systems integrate'glob"ally operating decision-making systems and locally cooperative learning neural net- works to enhance re+-timp operational responses to dynarnical environments examples of which include obstacle avoidance, res~onding to prevailing wind patterns, and overcoming other natural obscurants or in- terferences. Collectively',tkensor nefirons with simple properties, interacting according to basic community rules, can accomplish complex interconnecting functions such as generalization, error correction, pattern recognition, sensor fusion, and localization. Neural nets provide a greater degree of robusmess and fault tolerance than conventional systems in that minor variations or imperfections do not impair performance. The robotic platforms would be equipped with sensor devices that perform opticaI detection of biologicais in combination with multivariate chemical analysis tools based on genetic and neural network algorithms, laser-diode LIDAR analysis, ultra-wideband short-pulsed transmitting and receiving antennas, thermal im- a:ing sensors, and optical Communication technology providing robust data throughput pathways. Mission scenarios under consideration include ground penetrating radar (GPR) for detection of underground struc- tures, airborne systems, and plume migration and mitigation. We will describe our research in

  5. RF switching network: a novel technique for IR sensing

    NASA Astrophysics Data System (ADS)

    Mechtel, Deborah M.; Jenkins, R. Brian; Joyce, Peter J.; Nelson, Charles L.

    2016-05-01

    Rapid sensing of near infrared (IR) energy on a composite structure would provide information that could mitigate damage to composite structures. This paper describes a novel technique that implements photoconductive sensors in a radio frequency (RF) switching network designed to locate in real time the position and intensity of IR radiation incident on a composite structure. In the implementation described here, photoconductive sensors act as rapid response switches in a two layer RF network embedded in an FR-4 laminate. To detect radiation, phosphorous doped silicon photoconductive sensors are inserted in GHz range RF transmission lines. Photoconductive sensors use semiconductor materials that are optically sensitive at material dependent wavelengths. Incident radiation at the appropriate wavelength produces hole-electron pairs, so that the semiconductor becomes a conductor. By permitting signal propagation only when a sensor is illuminated, the RF signals are selectively routed from the lower layer transmission lines to the upper layer lines, thereby pinpointing the location and strength of incident radiation on a structure. Simulations based on a high frequency 3D planar electromagnetics model are presented and compared to experimental results. Experimental results are described for GHz range RF signal control for 300 mW and 180 mW incident energy from 975 nm and 1060 nm wavelength lasers respectively, where upon illumination, RF transmission line signal output power doubled when compared to non-illuminated results. Experimental results are reported for 100 W incident energy from a 1060 nm laser. Test results illustrate that real-time signal processing would permit a structure or vehicle to be controlled in response to incident radiation

  6. Adaptive Remote-Sensing Techniques Implementing Swarms of Mobile Agents

    SciTech Connect

    Cameron, S.M.; Loubriel, G.M.; Rbinett, R.D. III; Stantz, K.M.; Trahan, M.W.; Wagner, J.S.

    1999-04-01

    This paper focuses on our recent work at Sandia National Laboratories toward engineering a physics-based swarm of mobile vehicles for distributed sensing applications. Our goal is to coordinate a sensor array that optimizes sensor coverage and multivariate signal analysis by implementing artificial intelligence and evolutionary computational techniques. These intelligent control systems integrate both globally operating decision-making systems and locally cooperative information-sharing modes using genetically-trained neural networks. Once trained, neural networks have the ability to enhance real-time operational responses to dynamical environments, such as obstacle avoidance, responding to prevailing wind patterns, and overcoming other natural obscurants or interferences (jammers). The swarm realizes a collective set of sensor neurons with simple properties incorporating interactions based on basic community rules (potential fields) and complex interconnecting functions based on various neural network architectures, Therefore, the swarm is capable of redundant heterogeneous measurements which furnishes an additional degree of robustness and fault tolerance not afforded by conventional systems, while accomplishing such cognitive tasks as generalization, error correction, pattern recognition, and sensor fission. The robotic platforms could be equipped with specialized sensor devices including transmit/receive dipole antennas, chemical or biological sniffers in combination with recognition analysis tools, communication modulators, and laser diodes. Our group has been studying the collective behavior of an autonomous, multi-agent system applied to emerging threat applications. To accomplish such tasks, research in the fields of robotics, sensor technology, and swarms are being conducted within an integrated program. Mission scenarios under consideration include ground penetrating impulse radar (GPR) for detection of under-ground structures, airborne systems, and plume

  7. An overview of the development of remote sensing techniques for the screwworm eradication program

    NASA Technical Reports Server (NTRS)

    Barnes, C. M.; Forsberg, F. C.

    1975-01-01

    The current status of remote sensing techniques developed for the screwworm eradication program of the Mexican-American Screwworm Eradication Commission was reported. A review of the type of data and equipment used in the program is presented. Future applications of remote sensing techniques are considered.

  8. The definition of hydrologic model parameters using remote sensing techniques

    NASA Technical Reports Server (NTRS)

    Ragan, R. M.; Salomonson, V. V.

    1978-01-01

    The reported investigation is concerned with the use of Landsat remote sensing to define input parameters for an array of hydrologic models which are used to synthesize streamflow and water quality parameters in the planning or management process. The ground truth sampling and problems involved in translating the remotely sensed information into hydrologic model parameters are discussed. Questions related to the modification of existing models for compatibility with remote sensing capabilities are also examined. It is shown that the input parameters of many models are presently overdefined in terms of the sensitivity and accuracy of the model. When this overdefinition is recognized many of the models currently considered to be incompatible with remote sensing capabilities can be modified to make possible use with sensors having rather low resolutions.

  9. A Touch Sensing Technique Using the Effects of Extremely Low Frequency Fields on the Human Body

    PubMed Central

    Elfekey, Hatem; Bastawrous, Hany Ayad; Okamoto, Shogo

    2016-01-01

    Touch sensing is a fundamental approach in human-to-machine interfaces, and is currently under widespread use. Many current applications use active touch sensing technologies. Passive touch sensing technologies are, however, more adequate to implement low power or energy harvesting touch sensing interfaces. This paper presents a passive touch sensing technique based on the fact that the human body is affected by the surrounding extremely low frequency (ELF) electromagnetic fields, such as those of AC power lines. These external ELF fields induce electric potentials on the human body—because human tissues exhibit some conductivity at these frequencies—resulting in what is called AC hum. We therefore propose a passive touch sensing system that detects this hum noise when a human touch occurs, thus distinguishing between touch and non-touch events. The effectiveness of the proposed technique is validated by designing and implementing a flexible touch sensing keyboard. PMID:27918416

  10. A Touch Sensing Technique Using the Effects of Extremely Low Frequency Fields on the Human Body.

    PubMed

    Elfekey, Hatem; Bastawrous, Hany Ayad; Okamoto, Shogo

    2016-12-02

    Touch sensing is a fundamental approach in human-to-machine interfaces, and is currently under widespread use. Many current applications use active touch sensing technologies. Passive touch sensing technologies are, however, more adequate to implement low power or energy harvesting touch sensing interfaces. This paper presents a passive touch sensing technique based on the fact that the human body is affected by the surrounding extremely low frequency (ELF) electromagnetic fields, such as those of AC power lines. These external ELF fields induce electric potentials on the human body-because human tissues exhibit some conductivity at these frequencies-resulting in what is called AC hum. We therefore propose a passive touch sensing system that detects this hum noise when a human touch occurs, thus distinguishing between touch and non-touch events. The effectiveness of the proposed technique is validated by designing and implementing a flexible touch sensing keyboard.

  11. Techniques for sensing methanol concentration in aqueous environments

    NASA Technical Reports Server (NTRS)

    Narayanan, Sekharipuram R. (Inventor); Chun, William (Inventor); Valdez, Thomas I. (Inventor)

    2001-01-01

    An analyte concentration sensor that is capable of fast and reliable sensing of analyte concentration in aqueous environments with high concentrations of the analyte. Preferably, the present invention is a methanol concentration sensor device coupled to a fuel metering control system for use in a liquid direct-feed fuel cell.

  12. An unsupervised classification technique for multispectral remote sensing data.

    NASA Technical Reports Server (NTRS)

    Su, M. Y.; Cummings, R. E.

    1973-01-01

    Description of a two-part clustering technique consisting of (a) a sequential statistical clustering, which is essentially a sequential variance analysis, and (b) a generalized K-means clustering. In this composite clustering technique, the output of (a) is a set of initial clusters which are input to (b) for further improvement by an iterative scheme. This unsupervised composite technique was employed for automatic classification of two sets of remote multispectral earth resource observations. The classification accuracy by the unsupervised technique is found to be comparable to that by traditional supervised maximum-likelihood classification techniques.

  13. Combining remote sensing techniques with simulation modelling for assessing rangeland resources

    USGS Publications Warehouse

    Hanson, J. D.; Anderson, G.L.; Haas, R.H.

    1992-01-01

    Simulation modelling and remote sensing techniques can be used to describe ecological processes. When used together, these tools can increase our understanding of the spatial variability of ecosystems. Remotely sensed data can be combined with simulation models for predicting the accumulation of plant biomass, as surrogate variables within the models, or as correlative information for monitoring entire eco‐regions.

  14. Investigation of remote sensing techniques of measuring soil moisture

    NASA Technical Reports Server (NTRS)

    Newton, R. W. (Principal Investigator); Blanchard, A. J.; Nieber, J. L.; Lascano, R.; Tsang, L.; Vanbavel, C. H. M.

    1981-01-01

    Major activities described include development and evaluation of theoretical models that describe both active and passive microwave sensing of soil moisture, the evaluation of these models for their applicability, the execution of a controlled field experiment during which passive microwave measurements were acquired to validate these models, and evaluation of previously acquired aircraft microwave measurements. The development of a root zone soil water and soil temperature profile model and the calibration and evaluation of gamma ray attenuation probes for measuring soil moisture profiles are considered. The analysis of spatial variability of soil information as related to remote sensing is discussed as well as the implementation of an instrumented field site for acquisition of soil moisture and meteorologic information for use in validating the soil water profile and soil temperature profile models.

  15. Remote Sensing of Turbulence Using Doppler LIDAR and Radar Techniques.

    NASA Astrophysics Data System (ADS)

    Faulkner, Dennis Allen

    The idea of remotely sensing turbulence is not a new idea but has not been achieved to any level of reliability. Severe weather patterns are easy to spot with both Doppler and conventional radar systems. The clear air and otherwise undistinguishable turbulence is the type that has been receiving a lot of publicity lately due to the number of personal injuries suffered aboard aircraft. The purpose of this paper is to investigate the phenomenology and feasibility of remotely sensing and measuring small scale turbulence of this type. The remote sensing device of particular interest in this effort is the lidar (acronym derived from light detection and ranging). Data from two different field programs were used to research this effort. Some data was also reduced from a radar experiment conducted out west as a proof of concept. Wind fields were measured with ground based NASA Marshall Space Flight Center (NASA/MSFC), Huntsville, Alabama, lidar; NOAA Wave Propagation Laboratory (NOAA/WPL), Boulder, Colorado, lidar; Stapleton International Airport, Denver, Colorado, Doppler radars; and with a NASA B-57B instrumented aircraft. The remotely sensed winds are compared in all cases with the in-situ aircraft measurements. It was found from this research that turbulence intensities measured by computing the lidar wind time history for each range gate and then calculating the rms value relative to the mean agree quite well with the aircraft intensities. The spectral width or second moment data from the lidar, however, does not correspond well with the aircraft measured intensities being consistently a factor of 2-3 or more higher. The radar data analyzed also showed promise with the results being very similar to the lidar. Overall, the results of the research show general agreement between winds measured with Doppler lidars/radars and the B-57 instrumented aircraft. Data from these field tests provided unique sets of data to examine the mean wind and turbulence measurements made by

  16. An integrated study of earth resources in the state of California using remote sensing techniques

    NASA Technical Reports Server (NTRS)

    1973-01-01

    University of California investigations to determine the usefulness of modern remote sensing techniques have concentrated on the water resources of the state. The studies consider in detail the supply, demand, and impact relationships.

  17. A forestry application simulation of man-machine techniques for analyzing remotely sensed data

    NASA Technical Reports Server (NTRS)

    Berkebile, J.; Russell, J.; Lube, B.

    1976-01-01

    The typical steps in the analysis of remotely sensed data for a forestry applications example are simulated. The example uses numerically-oriented pattern recognition techniques and emphasizes man-machine interaction.

  18. Development of analysis techniques for remote sensing of vegetation resources

    NASA Technical Reports Server (NTRS)

    Draeger, W. C.

    1972-01-01

    Various data handling and analysis techniques are summarized for evaluation of ERTS-A and supporting high flight imagery. These evaluations are concerned with remote sensors applied to wildland and agricultural vegetation resource inventory problems. Monitoring California's annual grassland, automatic texture analysis, agricultural ground data collection techniques, and spectral measurements are included.

  19. Remote Sensing Techniques as a Tool for Environmental Monitoring

    NASA Astrophysics Data System (ADS)

    Faisal, K.; AlAhmad, M.; Shaker, A.

    2012-07-01

    The disposal of the solid wastes in landfill sites should be properly monitored by analyzing samples from soil, water, and landfill gases within the landfill site. Nevertheless, ground monitoring systems require intensive efforts and cost. Furthermore, ground monitoring may be difficult to be achieved in large geographic extent. Remote sensing technology has been introduced for waste disposal management and monitoring effects of the landfill sites on the environment. In this paper, two case studies are presented in the Trail Road landfill, Ottawa, Canada and the Al-Jleeb landfill, Al-Farwanyah, Kuwait to evaluate the use of multi-temporal remote sensing images to monitor the landfill sites. The work objectives are: 1) to study the usability of multi-temporal Landsat images for landfill site monitoring by studying the land surface temperature (LST) in the Trail Road landfill, 2) to investigate the relationship between the LST and the amount of the landfill gas emitted in the Trail Road landfill, and 3) to use the multi-temporal LST images to detect the suspicious dumping areas within the Al-Jleeb landfill site. Free archive of multi-temporal Landsat images are obtained from the USGS EarthExplorer. The Landsat images are then atmospherically corrected and the LST images are derived from the thermal band of the corrected Landsat images. In the Trail Road landfill, the results reveal that the LST of the landfill site is always higher than the air temperature by 10°C in average as well as the surroundings. A correlation is also observed between the recorded emitted methane (CH4) from the ground monitoring stations and the LST derived from the Landsat images. Based on the findings in the Al-Jleeb landfill, five locations are identified as suspicious dumping areas by overlaying the highest LST contours generated from the multi-temporal LST images. The study demonstrates that the use of multi-temporal remote sensing images can provide supplementary information for

  20. Unified microwave moisture sensing technique for grain and seed

    NASA Astrophysics Data System (ADS)

    Trabelsi, Samir; Nelson, Stuart O.

    2007-04-01

    A unified method for moisture sensing in cereal grain and oilseed from a single calibration equation, which is obtained from measurement of dielectric properties at a single microwave frequency, is presented. The method is based on a complex permittivity calibration function that is independent of both bulk density and kind of material. Performance of the method was tested for soybeans, corn, wheat, sorghum, barley and oats at 7 GHz and about 23 °C. The standard error of calibration for moisture prediction from complex permittivity measurements was 0.8%.

  1. The application of remote sensing techniques: Technical and methodological issues

    NASA Technical Reports Server (NTRS)

    Polcyn, F. C.; Wagner, T. W.

    1974-01-01

    Capabilities and limitations of modern imaging electromagnetic sensor systems are outlined, and the products of such systems are compared with those of the traditional aerial photographic system. Focus is given to the interface between the rapidly developing remote sensing technology and the information needs of operational agencies, and communication gaps are shown to retard early adoption of the technology by these agencies. An assessment is made of the current status of imaging remote sensors and their potential for the future. Public sources of remote sensor data and several cost comparisons are included.

  2. A review of remote sensing techniques and related spectroscopy problems

    NASA Astrophysics Data System (ADS)

    Payan, Sébastien; de La Noë, Jérôme; Hauchecorne, Alain; Camy-Peyret, Claude

    2005-10-01

    Remote sensing based on quantitative spectroscopy is a powerful tool for precise measurements of atmospheric trace species concentrations, through the use of characteristic spectral signatures of the different molecular species and their associated vibration-rotation and electronic bands in the microwave, infrared, and UV-visible domains. A reliable retrieval of the concentration profiles requires a good characterisation of measurement and spectral fitting errors. This includes an accurate knowledge of spectroscopic parameters of all transition lines or absorption cross sections of interest since uncertainties lead to systematic retrieval errors. To cite this article: S. Payan et al., C. R. Physique 6 (2005).

  3. The application of remote sensing techniques to selected inter and intra urban data acquisition problems

    NASA Technical Reports Server (NTRS)

    Horton, F. E.

    1970-01-01

    The utility of remote sensing techniques to urban data acquisition problems in several distinct areas was identified. This endeavor included a comparison of remote sensing systems for urban data collection, the extraction of housing quality data from aerial photography, utilization of photographic sensors in urban transportation studies, urban change detection, space photography utilization, and an application of remote sensing techniques to the acquisition of data concerning intra-urban commercial centers. The systematic evaluation of variable extraction for urban modeling and planning at several different scales, and the model derivation for identifying and predicting economic growth and change within a regional system of cities are also studied.

  4. The application of remote sensing techniques to selected inter and intra urban data acquisition problems

    NASA Technical Reports Server (NTRS)

    Horton, F. E.

    1970-01-01

    The utility of remote sensing techniques to urban data acquisition problems in several distinct areas was identified. This endeavor included a comparison of remote sensing systems for urban data collection, the extraction of housing quality data from aerial photography, utilization of photographic sensors in urban transportation studies, urban change detection, space photography utilization, and an application of remote sensing techniques to the acquisition of data concerning intra-urban commercial centers. The systematic evaluation of variable extraction for urban modeling and planning at several different scales, and the model derivation for identifying and predicting economic growth and change within a regional system of cities are also studied.

  5. Remote sensing techniques for monitoring and managing irrigated lands

    NASA Astrophysics Data System (ADS)

    Allan, J. A.

    Agriculture in semi-arid tracts of the world depends on water to sustain its irrigation systems. Such agricultural systems either derive from government investments in the control of surface flow or they have been developed through the exploitation of groundwater sometimes by a large community of unsupervised individuals seeking to maximise their own advantage without concern for the resource upon which they depend in the medium and long term. In both cases government agencies need data on the area irrigated and the volume of water used. In countries with highly developed scientific and agricultural institutions the contribution of remote sensing, though significant, may only provide between five and ten per cent of the data required to guide regional and national managers. In countries without such institutions the proportion contributed by remote sensing can be very much higher, as shown in a recent study in North Africa. The paper will emphasise the importance of carefully structured sampling procedures, both to improve the areal estimates from satellite imagery and the estimates of water use based upon them. The role of satellite imagery in providing information on the status of water resources, on trends in water use and in the implementation of policies to extend or diminish irrigated land are discussed.

  6. Wave Propagation Through Inhomogeneities With Applications to Novel Sensing Techniques

    NASA Technical Reports Server (NTRS)

    Adamovsky, G.; Tokars, R.; Varga, D.; Floyd B.

    2008-01-01

    The paper describes phenomena observed as a result of laser pencil beam interactions with abrupt interfaces including aerodynamic shocks. Based on these phenomena, a novel flow visualization technique based on a laser scanning pencil beam is introduced. The technique reveals properties of light interaction with interfaces including aerodynamic shocks that are not seen using conventional visualization. Various configurations of scanning beam devices including those with no moving parts, as well as results of "proof-of-concept" tests, are included.

  7. Remote sensing techniques from helicopter for water quality and air pollution control

    SciTech Connect

    Geraci, A.L.; Landolina, F.F.

    1996-11-01

    Aircraft remote sensing provides a number of benefits, allowing to vary the detection parameters, giving better resolution, and being little affected by weather conditions and no replaceable under emergency situations. Also as a part of projects funded by the Commission of the European Communities, through the Regional Government of Sicily, applications of remote sensing techniques were carried out from helicopter over selected study areas in Sicily, for water quality and air pollution control. In particular, remotely-sensed data were acquired, using LASER techniques and thermal infrared imagery, for the monitoring of water quality and the assessment of oil pollution. Furthermore, air quality was investigated, using LASER techniques and correlation spectroscopy. In a perspective of integration, the investigations carried out proved effective and useful, confirming the important role of the helicopter as monitoring platform for environmental remote sensing applications. 6 refs., 11 figs.

  8. California nearshore surface currents. [monitoring by remote sensing techniques

    NASA Technical Reports Server (NTRS)

    Pirie, D. M.; Murphy, M. J.; Edmisten, J. R.

    1975-01-01

    During the oceanic period from July to November, the southward flowing California current dominates the nearshore current patterns. Commencing about the middle of November and extending to mid-February, the Davidson current, a northward moving countercurrent, is the dominant inshore transporter of water and suspensates. The phenomenon of upwelling is prevalent during the period from the middle of February to the end of July. Thus, every year along the coast of California, there are three successive current seasons: the oceanic, the Davidson, and the upwelling. This paper is a discussion of the nature of these nearshore currents. In addition, the capabilities of various remote sensing platforms and systems for providing methods of monitoring the coastal processes associated with the current seasons of California are demonstrated herein.

  9. Time-frequency signal processing techniques for radar remote sensing

    NASA Astrophysics Data System (ADS)

    Wen, Chun-Hsien

    The Arecibo 430 MHz Incoherent Scatter Radar (ISR) has been used to observe the vertical ionospheric electron concentration profiles for many years. Earlier studies are dated back to 1970s. The meteor observations grew from the ISR observations of the ionosphere in the last 10 years. The techniques for meteor observation have evolved significantly since then. It has become a regular observation at Arecibo Observatory (AO). In this work we introduce signal processing techniques to detect meteor events and determine their parameters for the meteor observation data. We also propose techniques to separate the meteor and the incoherent scatter signals for the ISR observation data. The large aperture AO radar is susceptible to the interference from other communication systems because of its sensitivity. The interference contaminates the radar data and sometimes seriously degrades the performance of the meteor detection. We introduce signal processing techniques to remove the interference for both the meteor and the ISR observation data in this work. Other applications for proposed techniques are introduced in this work too.

  10. Head-mounted active noise control system with virtual sensing technique

    NASA Astrophysics Data System (ADS)

    Miyazaki, Nobuhiro; Kajikawa, Yoshinobu

    2015-03-01

    In this paper, we apply a virtual sensing technique to a head-mounted active noise control (ANC) system we have already proposed. The proposed ANC system can reduce narrowband noise while improving the noise reduction ability at the desired locations. A head-mounted ANC system based on an adaptive feedback structure can reduce noise with periodicity or narrowband components. However, since quiet zones are formed only at the locations of error microphones, an adequate noise reduction cannot be achieved at the locations where error microphones cannot be placed such as near the eardrums. A solution to this problem is to apply a virtual sensing technique. A virtual sensing ANC system can achieve higher noise reduction at the desired locations by measuring the system models from physical sensors to virtual sensors, which will be used in the online operation of the virtual sensing ANC algorithm. Hence, we attempt to achieve the maximum noise reduction near the eardrums by applying the virtual sensing technique to the head-mounted ANC system. However, it is impossible to place the microphone near the eardrums. Therefore, the system models from physical sensors to virtual sensors are estimated using the Head And Torso Simulator (HATS) instead of human ears. Some simulation, experimental, and subjective assessment results demonstrate that the head-mounted ANC system with virtual sensing is superior to that without virtual sensing in terms of the noise reduction ability at the desired locations.

  11. The application analysis of the multi-angle polarization technique for ocean color remote sensing

    NASA Astrophysics Data System (ADS)

    Zhang, Yongchao; Zhu, Jun; Yin, Huan; Zhang, Keli

    2017-02-01

    The multi-angle polarization technique, which uses the intensity of polarized radiation as the observed quantity, is a new remote sensing means for earth observation. With this method, not only can the multi-angle light intensity data be provided, but also the multi-angle information of polarized radiation can be obtained. So, the technique may solve the problems, those could not be solved with the traditional remote sensing methods. Nowadays, the multi-angle polarization technique has become one of the hot topics in the field of the international quantitative research on remote sensing. In this paper, we firstly introduce the principles of the multi-angle polarization technique, then the situations of basic research and engineering applications are particularly summarized and analysed in 1) the peeled-off method of sun glitter based on polarization, 2) the ocean color remote sensing based on polarization, 3) oil spill detection using polarization technique, 4) the ocean aerosol monitoring based on polarization. Finally, based on the previous work, we briefly present the problems and prospects of the multi-angle polarization technique used in China's ocean color remote sensing.

  12. Update and review of accuracy assessment techniques for remotely sensed data

    NASA Technical Reports Server (NTRS)

    Congalton, R. G.; Heinen, J. T.; Oderwald, R. G.

    1983-01-01

    Research performed in the accuracy assessment of remotely sensed data is updated and reviewed. The use of discrete multivariate analysis techniques for the assessment of error matrices, the use of computer simulation for assessing various sampling strategies, and an investigation of spatial autocorrelation techniques are examined.

  13. Detection of asphalt pavement cracks using remote sensing techniques

    NASA Astrophysics Data System (ADS)

    Mettas, Christodoulos; Agapiou, Athos; Themistocleous, Kyriacos; Neocleous, Kyriacos; Hadjimitsis, Diofantos G.

    2016-10-01

    Deterioration of asphalt road pavements is inevitable throughout its life cycle. There are several types of deterioration that take place on these surfaces, like surface defects and deformations. One of the most common asphalt defects is cracking. Fatigue, transverse, longitudinal, reflective, edge, block and slippage are types of cracking that can be observed anywhere in the world. Monitoring and preventative/periodic maintenance of these types of wears are two very important actions that have to take place to avoid "costly" solutions. This paper aims to introduce the spectral characteristics of uncracked (healthy) and cracked asphalt surfaces which can give a new asphalt crack index. This is performed through remote sensing applications in the area of asphalt pavements. Multispectral images can be elaborated using the index to enhance crack marks on asphalt surfaces. Ground spectral signatures were acquired from both uncracked and cracked asphalted areas of Cyprus (Limassol). Evaluation separability indices can be used to identify the optimum wavelength regions that can distinguish better the uncracked and cracked asphalt surfaces. The results revealed that the spectral sensitivity for the enhancement of cracked asphalt was detected using the Euclidean, Mahalanobis and Cosine Distance Indices in the Vis range (approximately at 450 nm) and in the SWIR 1 range (approximately at 1750 nm).

  14. The value of remote sensing techniques in supporting effective extrapolation across multiple marine spatial scales.

    PubMed

    Strong, James Asa; Elliott, Michael

    2017-03-15

    The reporting of ecological phenomena and environmental status routinely required point observations, collected with traditional sampling approaches to be extrapolated to larger reporting scales. This process encompasses difficulties that can quickly entrain significant errors. Remote sensing techniques offer insights and exceptional spatial coverage for observing the marine environment. This review provides guidance on (i) the structures and discontinuities inherent within the extrapolative process, (ii) how to extrapolate effectively across multiple spatial scales, and (iii) remote sensing techniques and data sets that can facilitate this process. This evaluation illustrates that remote sensing techniques are a critical component in extrapolation and likely to underpin the production of high-quality assessments of ecological phenomena and the regional reporting of environmental status. Ultimately, is it hoped that this guidance will aid the production of robust and consistent extrapolations that also make full use of the techniques and data sets that expedite this process.

  15. Noninvasive in vivo glucose sensing using an iris based technique

    NASA Astrophysics Data System (ADS)

    Webb, Anthony J.; Cameron, Brent D.

    2011-03-01

    Physiological glucose monitoring is important aspect in the treatment of individuals afflicted with diabetes mellitus. Although invasive techniques for glucose monitoring are widely available, it would be very beneficial to make such measurements in a noninvasive manner. In this study, a New Zealand White (NZW) rabbit animal model was utilized to evaluate a developed iris-based imaging technique for the in vivo measurement of physiological glucose concentration. The animals were anesthetized with isoflurane and an insulin/dextrose protocol was used to control blood glucose concentration. To further help restrict eye movement, a developed ocular fixation device was used. During the experimental time frame, near infrared illuminated iris images were acquired along with corresponding discrete blood glucose measurements taken with a handheld glucometer. Calibration was performed using an image based Partial Least Squares (PLS) technique. Independent validation was also performed to assess model performance along with Clarke Error Grid Analysis (CEGA). Initial validation results were promising and show that a high percentage of the predicted glucose concentrations are within 20% of the reference values.

  16. Remote sensing of lunar color differences using isoluminous enhancement techniques.

    NASA Technical Reports Server (NTRS)

    Yost, E.; Anderson, R.; Goetz, A.

    1972-01-01

    An isoluminous method of processing and viewing multispectral lunar imagery was developed in an effort to enhance the very subtle color variations seen on the lunar surface. The new technique normalizes the achromatic shades of gray to a common value and displays any small spectral reflectivity shifts as vivid colors. The primary advantage of the isoluminous method is its ability to present two objects (having the same spectral distribution) as the exact same color on the viewer screen regardless of any brightness difference which may exist between the two.

  17. Remote sensing techniques for conservation and management of natural vegetation ecosystems

    NASA Technical Reports Server (NTRS)

    Parada, N. D. J. (Principal Investigator); Verdesio, J. J.; Dossantos, J. R.

    1981-01-01

    The importance of using remote sensing techniques, in the visible and near-infrared ranges, for mapping, inventory, conservation and management of natural ecosystems is discussed. Some examples realized in Brazil or other countries are given to evaluate the products from orbital platform (MSS and RBV imagery of LANDSAT) and aerial level (photography) for ecosystems study. The maximum quantitative and qualitative information which can be obtained from each sensor, at different level, are discussed. Based on the developed experiments it is concluded that the remote sensing technique is a useful tool in mapping vegetation units, estimating biomass, forecasting and evaluation of fire damage, disease detection, deforestation mapping and change detection in land-use. In addition, remote sensing techniques can be used in controling implantation and planning natural/artificial regeneration.

  18. Improved Battery State Estimation Using Novel Sensing Techniques

    NASA Astrophysics Data System (ADS)

    Abdul Samad, Nassim

    Lithium-ion batteries have been considered a great complement or substitute for gasoline engines due to their high energy and power density capabilities among other advantages. However, these types of energy storage devices are still yet not widespread, mainly because of their relatively high cost and safety issues, especially at elevated temperatures. This thesis extends existing methods of estimating critical battery states using model-based techniques augmented by real-time measurements from novel temperature and force sensors. Typically, temperature sensors are located near the edge of the battery, and away from the hottest core cell regions, which leads to slower response times and increased errors in the prediction of core temperatures. New sensor technology allows for flexible sensor placement at the cell surface between cells in a pack. This raises questions about the optimal locations of these sensors for best observability and temperature estimation. Using a validated model, which is developed and verified using experiments in laboratory fixtures that replicate vehicle pack conditions, it is shown that optimal sensor placement can lead to better and faster temperature estimation. Another equally important state is the state of health or the capacity fading of the cell. This thesis introduces a novel method of using force measurements for capacity fade estimation. Monitoring capacity is important for defining the range of electric vehicles (EVs) and plug-in hybrid electric vehicles (PHEVs). Current capacity estimation techniques require a full discharge to monitor capacity. The proposed method can complement or replace current methods because it only requires a shallow discharge, which is especially useful in EVs and PHEVs. Using the accurate state estimation accomplished earlier, a method for downsizing a battery pack is shown to effectively reduce the number of cells in a pack without compromising safety. The influence on the battery performance (e

  19. Radio frequency switching network: a technique for infrared sensing

    NASA Astrophysics Data System (ADS)

    Mechtel, Deborah M.; Jenkins, R. Brian; Joyce, Peter J.; Nelson, Charles L.

    2016-10-01

    This paper describes a unique technique that implements photoconductive sensors in a radio frequency (RF) switching network designed to locate in real-time the position and intensity of IR radiation incident on a composite structure. In the implementation described here, photoconductive sensors act as rapid response switches in a two-layer RF network embedded in an FR-4 laminate. To detect radiation, phosphorous-doped silicon photoconductive sensors are inserted in GHz range RF transmission lines. By permitting signal propagation only when a sensor is illuminated, the RF signals are selectively routed from lower layer transmission lines to upper layer lines, thereby pinpointing the location and strength of incident radiation. Simulations based on a high frequency three-dimensional planar electromagnetics model are presented and compared to the experimental results. The experimental results are described for GHz range RF signal control for 300- and 180-mW incident energy from 975- to 1060-nm wavelength lasers, respectively, where upon illumination, RF transmission line signal output power doubled when compared to nonilluminated results. The experimental results are also reported for 100-W incident energy from a 1060-nm laser. Test results illustrate real-time signal processing would permit a structure to be controlled in response to incident radiation.

  20. Remote sensing of stress using electro-optics imaging technique

    NASA Astrophysics Data System (ADS)

    Chen, Tong; Yuen, Peter; Hong, Kan; Tsitiridis, Aristeidis; Kam, Firmin; Jackman, James; James, David; Richardson, Mark; Oxford, William; Piper, Jonathan; Thomas, Francis; Lightman, Stafford

    2009-09-01

    Emotional or physical stresses induce a surge of adrenaline in the blood stream under the command of the sympathetic nerve system, which, cannot be suppressed by training. The onset of this alleviated level of adrenaline triggers a number of physiological chain reactions in the body, such as dilation of pupil and an increased feed of blood to muscles etc. This paper reports for the first time how Electro-Optics (EO) technologies such as hyperspectral [1,2] and thermal imaging[3] methods can be used for the detection of stress remotely. Preliminary result using hyperspectral imaging technique has shown a positive identification of stress through an elevation of haemoglobin oxygenation saturation level in the facial region, and the effect is seen more prominently for the physical stressor than the emotional one. However, all results presented so far in this work have been interpreted together with the base line information as the reference point, and that really has limited the overall usefulness of the developing technology. The present result has highlighted this drawback and it prompts for the need of a quantitative assessment of the oxygenation saturation and to correlate it directly with the stress level as the top priority of the next stage of research.

  1. Introduction to This Special Issue on Geostatistics and Geospatial Techniques in Remote Sensing

    NASA Technical Reports Server (NTRS)

    Atkinson, Peter; Quattrochi, Dale A.; Goodman, H. Michael (Technical Monitor)

    2000-01-01

    The germination of this special Computers & Geosciences (C&G) issue began at the Royal Geographical Society (with the Institute of British Geographers) (RGS-IBG) annual meeting in January 1997 held at the University of Exeter, UK. The snow and cold of the English winter were tempered greatly by warm and cordial discussion of how to stimulate and enhance cooperation on geostatistical and geospatial research in remote sensing 'across the big pond' between UK and US researchers. It was decided that one way forward would be to hold parallel sessions in 1998 on geostatistical and geospatial research in remote sensing at appropriate venues in both the UK and the US. Selected papers given at these sessions would be published as special issues of C&G on the UK side and Photogrammetric Engineering and Remote Sensing (PE&RS) on the US side. These issues would highlight the commonality in research on geostatistical and geospatial research in remote sensing on both sides of the Atlantic Ocean. As a consequence, a session on "Geostatistics and Geospatial Techniques for Remote Sensing of Land Surface Processes" was held at the RGS-IBG annual meeting in Guildford, Surrey, UK in January 1998, organized by the Modeling and Advanced Techniques Special Interest Group (MAT SIG) of the Remote Sensing Society (RSS). A similar session was held at the Association of American Geographers (AAG) annual meeting in Boston, Massachusetts in March 1998, sponsored by the AAG's Remote Sensing Specialty Group (RSSG). The 10 papers that make up this issue of C&G, comprise 7 papers from the UK and 3 papers from the LIS. We are both co-editors of each of the journal special issues, with the lead editor of each journal issue being from their respective side of the Atlantic. The special issue of PE&RS (vol. 65) that constitutes the other half of this co-edited journal series was published in early 1999, comprising 6 papers by US authors. We are indebted to the International Association for Mathematical

  2. Introduction to This Special Issue on Geostatistics and Geospatial Techniques in Remote Sensing

    NASA Technical Reports Server (NTRS)

    Atkinson, Peter; Quattrochi, Dale A.; Goodman, H. Michael (Technical Monitor)

    2000-01-01

    The germination of this special Computers & Geosciences (C&G) issue began at the Royal Geographical Society (with the Institute of British Geographers) (RGS-IBG) annual meeting in January 1997 held at the University of Exeter, UK. The snow and cold of the English winter were tempered greatly by warm and cordial discussion of how to stimulate and enhance cooperation on geostatistical and geospatial research in remote sensing 'across the big pond' between UK and US researchers. It was decided that one way forward would be to hold parallel sessions in 1998 on geostatistical and geospatial research in remote sensing at appropriate venues in both the UK and the US. Selected papers given at these sessions would be published as special issues of C&G on the UK side and Photogrammetric Engineering and Remote Sensing (PE&RS) on the US side. These issues would highlight the commonality in research on geostatistical and geospatial research in remote sensing on both sides of the Atlantic Ocean. As a consequence, a session on "Geostatistics and Geospatial Techniques for Remote Sensing of Land Surface Processes" was held at the RGS-IBG annual meeting in Guildford, Surrey, UK in January 1998, organized by the Modeling and Advanced Techniques Special Interest Group (MAT SIG) of the Remote Sensing Society (RSS). A similar session was held at the Association of American Geographers (AAG) annual meeting in Boston, Massachusetts in March 1998, sponsored by the AAG's Remote Sensing Specialty Group (RSSG). The 10 papers that make up this issue of C&G, comprise 7 papers from the UK and 3 papers from the LIS. We are both co-editors of each of the journal special issues, with the lead editor of each journal issue being from their respective side of the Atlantic. The special issue of PE&RS (vol. 65) that constitutes the other half of this co-edited journal series was published in early 1999, comprising 6 papers by US authors. We are indebted to the International Association for Mathematical

  3. The investigation of advanced remote sensing techniques for the measurement of aerosol characteristics

    NASA Technical Reports Server (NTRS)

    Deepak, A.; Becher, J.

    1979-01-01

    Advanced remote sensing techniques and inversion methods for the measurement of characteristics of aerosol and gaseous species in the atmosphere were investigated. Of particular interest were the physical and chemical properties of aerosols, such as their size distribution, number concentration, and complex refractive index, and the vertical distribution of these properties on a local as well as global scale. Remote sensing techniques for monitoring of tropospheric aerosols were developed as well as satellite monitoring of upper tropospheric and stratospheric aerosols. Computer programs were developed for solving multiple scattering and radiative transfer problems, as well as inversion/retrieval problems. A necessary aspect of these efforts was to develop models of aerosol properties.

  4. Rapid Damage Assessment Using High-resolution Remote Sensing Imagery: Tools and Techniques

    SciTech Connect

    Vatsavai, Raju; Tuttle, Mark A; Bhaduri, Budhendra L; Bright, Eddie A; Cheriyadat, Anil M; Chandola, Varun; Graesser, Jordan B

    2011-01-01

    Accurate damage assessment caused by major natural and anthropogenic disasters is becoming critical due to increases in human and economic loss. This increase in loss of life and severe damages can be attributed to growing population, as well as human migration to disaster prone regions of the world. Rapid damage assessment and dissemination of accurate information is critical for creating an effective emergency response. Remote sensing and geographic information systems (GIS) based techniques and tools are important in disaster damage assessment and reporting activities. In this review, we will look into the state of the art techniques in damage assessment using remote sensing and GIS.

  5. Universal and efficient compressed sensing by spread spectrum and application to realistic Fourier imaging techniques

    NASA Astrophysics Data System (ADS)

    Puy, Gilles; Vandergheynst, Pierre; Gribonval, Rémi; Wiaux, Yves

    2012-12-01

    We advocate a compressed sensing strategy that consists of multiplying the signal of interest by a wide bandwidth modulation before projection onto randomly selected vectors of an orthonormal basis. First, in a digital setting with random modulation, considering a whole class of sensing bases including the Fourier basis, we prove that the technique is universal in the sense that the required number of measurements for accurate recovery is optimal and independent of the sparsity basis. This universality stems from a drastic decrease of coherence between the sparsity and the sensing bases, which for a Fourier sensing basis relates to a spread of the original signal spectrum by the modulation (hence the name "spread spectrum"). The approach is also efficient as sensing matrices with fast matrix multiplication algorithms can be used, in particular in the case of Fourier measurements. Second, these results are confirmed by a numerical analysis of the phase transition of the ℓ1-minimization problem. Finally, we show that the spread spectrum technique remains effective in an analog setting with chirp modulation for application to realistic Fourier imaging. We illustrate these findings in the context of radio interferometry and magnetic resonance imaging.

  6. Successful integration of remote sensing and ground based exploration techniques in an arid environment

    SciTech Connect

    Jones, R.F.E. ); Oehlers, M. )

    1995-03-06

    Twenty years ago, remote sensing promised to revolutionize exploration; unfortunately, many of the early promises made were unfulfilled and remote sensing tended to drop out of mainstream exploration. Both these extremes are unrealistic, and projects undertaken by Clyde in Yemen illustrate some of the ways remote sensing can become a successful and cost-effective part of an exploration program. Firstly, the remote sensed data, integrated with a minimum of ground control work, provided maps to use in subsequent fieldwork, a surface geology map, and a digital elevation model with its derived topographic contour maps. Secondly, the remote sensed data enabled the authors to create a structural contour map of a near surface horizon at a very low cost per square kilometer. Thirdly, the remote sensed data became a crucial planning tool for seismic operations to optimize data quality and minimize acquisition cost without having to resort to costly and time-consuming swath shooting or similar high-effort techniques. Finally, the surface geological map derived from the image interpretation enabled them to create geological cross sections along the shot seismic lines in a matter of hours without having a field geologist mapping along the lines. Remote sensing can provide highly cost-effective benefits to an exploration program in an arid region, and many of the applications can also be developed for use in areas with vegetation cover.

  7. Surveillance of Arthropod Vector-Borne Infectious Diseases Using Remote Sensing Techniques: A Review

    PubMed Central

    Kalluri, Satya; Gilruth, Peter; Rogers, David; Szczur, Martha

    2007-01-01

    Epidemiologists are adopting new remote sensing techniques to study a variety of vector-borne diseases. Associations between satellite-derived environmental variables such as temperature, humidity, and land cover type and vector density are used to identify and characterize vector habitats. The convergence of factors such as the availability of multi-temporal satellite data and georeferenced epidemiological data, collaboration between remote sensing scientists and biologists, and the availability of sophisticated, statistical geographic information system and image processing algorithms in a desktop environment creates a fertile research environment. The use of remote sensing techniques to map vector-borne diseases has evolved significantly over the past 25 years. In this paper, we review the status of remote sensing studies of arthropod vector-borne diseases due to mosquitoes, ticks, blackflies, tsetse flies, and sandflies, which are responsible for the majority of vector-borne diseases in the world. Examples of simple image classification techniques that associate land use and land cover types with vector habitats, as well as complex statistical models that link satellite-derived multi-temporal meteorological observations with vector biology and abundance, are discussed here. Future improvements in remote sensing applications in epidemiology are also discussed. PMID:17967056

  8. Optical technique for photovoltaic spatial current response measurements using compressive sensing and random binary projections

    NASA Astrophysics Data System (ADS)

    Cashmore, Matt. T.; Koutsourakis, George; Gottschalg, Ralph; Hall, Simon. R. G.

    2016-04-01

    Compressive sensing has been widely used in image compression and signal recovery techniques in recent years; however, it has received limited attention in the field of optical measurement. This paper describes the use of compressive sensing for measurements of photovoltaic (PV) solar cells, using fully random sensing matrices, rather than mapping an orthogonal basis set directly. Existing compressive sensing systems optically image the surface of the object under test, this contrasts with the method described, where illumination patterns defined by precalculated sensing matrices, probe PV devices. We discuss the use of spatially modulated light fields to probe a PV sample to produce a photocurrent map of the optical response. This allows for faster measurements than would be possible using traditional translational laser beam induced current techniques. Results produced to a 90% correlation to raster scanned measurements, which can be achieved with under 25% of the conventionally required number of data points. In addition, both crack and spot type defects are detected at resolutions comparable to electroluminescence techniques, with 50% of the number of measurements required for a conventional scan.

  9. Surveillance of arthropod vector-borne infectious diseases using remote sensing techniques: a review.

    PubMed

    Kalluri, Satya; Gilruth, Peter; Rogers, David; Szczur, Martha

    2007-10-26

    Epidemiologists are adopting new remote sensing techniques to study a variety of vector-borne diseases. Associations between satellite-derived environmental variables such as temperature, humidity, and land cover type and vector density are used to identify and characterize vector habitats. The convergence of factors such as the availability of multi-temporal satellite data and georeferenced epidemiological data, collaboration between remote sensing scientists and biologists, and the availability of sophisticated, statistical geographic information system and image processing algorithms in a desktop environment creates a fertile research environment. The use of remote sensing techniques to map vector-borne diseases has evolved significantly over the past 25 years. In this paper, we review the status of remote sensing studies of arthropod vector-borne diseases due to mosquitoes, ticks, blackflies, tsetse flies, and sandflies, which are responsible for the majority of vector-borne diseases in the world. Examples of simple image classification techniques that associate land use and land cover types with vector habitats, as well as complex statistical models that link satellite-derived multi-temporal meteorological observations with vector biology and abundance, are discussed here. Future improvements in remote sensing applications in epidemiology are also discussed.

  10. Frequency-Shifted Interferometry — A Versatile Fiber-Optic Sensing Technique

    PubMed Central

    Ye, Fei; Zhang, Yiwei; Qi, Bing; Qian, Li

    2014-01-01

    Fiber-optic sensing is a field that is developing at a fast pace. Novel fiber-optic sensor designs and sensing principles constantly open doors for new opportunities. In this paper, we review a fiber-optic sensing technique developed in our research group called frequency-shifted interferometry (FSI). This technique uses a continuous-wave light source, an optical frequency shifter, and a slow detector. We discuss the operation principles of several FSI implementations and show their applications in fiber length and dispersion measurement, locating weak reflections along a fiber link, fiber-optic sensor multiplexing, and high-sensitivity cavity ring-down measurement. Detailed analysis of FSI system parameters is also presented. PMID:24955943

  11. Recurrent potential pulse technique for improvement of glucose sensing ability of 3D polypyrrole

    NASA Astrophysics Data System (ADS)

    Cysewska, Karolina; Karczewski, Jakub; Jasiński, Piotr

    2017-07-01

    In this work, a new approach for using a 3D polypyrrole (PPy) conducting polymer as a sensing material for glucose detection is proposed. Polypyrrole is electrochemically polymerized on a platinum screen-printed electrode in an aqueous solution of lithium perchlorate and pyrrole. PPy exhibits a high electroactive surface area and high electrochemical stability, which results in it having excellent electrocatalytic properties. The studies show that using the recurrent potential pulse technique results in an increase in PPy sensing stability, compared to the amperometric approach. This is due to the fact that the technique, under certain parameters, allows the PPy redox properties to be fully utilized, whilst preventing its anodic degradation. Because of this, the 3D PPy presented here has become a very good candidate as a sensing material for glucose detection, and can work without any additional dopants, mediators or enzymes.

  12. Observations of the global structure of the stratosphere and mesosphere with sounding rockets and with remote sensing techniques from satellites

    NASA Technical Reports Server (NTRS)

    Heath, D. F.; Hilsenrath, E.; Krueger, A. J.; Nordberg, W.; Prabhakara, C.; Theon, J. S.

    1972-01-01

    Brief descriptions are given of the techniques involved in determining the global structure of the mesosphere and stratosphere based on sounding rocket observations and satellite remotely sensed measurements.

  13. The application of remote sensing techniques to the study of ophiolites

    NASA Astrophysics Data System (ADS)

    Khan, Shuhab D.; Mahmood, Khalid

    2008-08-01

    Satellite remote sensing methods are a powerful tool for detailed geologic analysis, especially in inaccessible regions of the earth's surface. Short-wave infrared (SWIR) bands are shown to provide spectral information bearing on the lithologic, structural, and geochemical character of rock bodies such as ophiolites, allowing for a more comprehensive assessment of the lithologies present, their stratigraphic relationships, and geochemical character. Most remote sensing data are widely available for little or no cost, along with user-friendly software for non-specialists. In this paper we review common remote sensing systems and methods that allow for the discrimination of solid rock (lithologic) components of ophiolite complexes and their structural relationships. Ophiolites are enigmatic rock bodies which associated with most, if not all, plate collision sutures. Ophiolites are ideal for remote sensing given their widely recognized diversity of lithologic types and structural relationships. Accordingly, as a basis for demonstrating the utility of remote sensing techniques, we briefly review typical ophiolites in the Tethyan tectonic belt. As a case study, we apply integrated remote sensing studies of a well-studied example, the Muslim Bagh ophiolite, located in Balochistan, western Pakistan. On this basis, we attempt to demonstrate how remote sensing data can validate and reconcile existing information obtained from field studies. The lithologic and geochemical diversity of Muslim Bagh are representative of Tethyan ophiolites. Despite it's remote location it has been extensively mapped and characterized by structural and geochemical studies, and is virtually free of vegetative cover. Moreover, integrating the remote sensing data with 'ground truth' information thus offers the potential of an improved template for interpreting remote sensing data sets of other ophiolites for which little or no field information is available.

  14. A solar energy estimation procedure using remote sensing techniques. [watershed hydrologic models

    NASA Technical Reports Server (NTRS)

    Khorram, S.

    1977-01-01

    The objective of this investigation is to design a remote sensing-aided procedure for daily location-specific estimation of solar radiation components over the watershed(s) of interest. This technique has been tested on the Spanish Creek Watershed, Northern California, with successful results.

  15. A solar energy estimation procedure using remote sensing techniques. [watershed hydrologic models

    NASA Technical Reports Server (NTRS)

    Khorram, S.

    1977-01-01

    The objective of this investigation is to design a remote sensing-aided procedure for daily location-specific estimation of solar radiation components over the watershed(s) of interest. This technique has been tested on the Spanish Creek Watershed, Northern California, with successful results.

  16. Development of techniques required for the application of a laser to three dimensional visual sensing

    NASA Technical Reports Server (NTRS)

    Ryan, Arthur M.; Gerhardt, Lester A.

    1991-01-01

    The ongoing vision research at the Center for Intelligent Robotic Systems for Space Exploration (CIRSSE) is directed toward identifying and addressing the relevant issues involved in applying visual sensing to space assembly tasks. A considerable amount of effort has been devoted to passive sensing techniques such as using multiple cameras to identify objects in a scene. To compliment the capabilities of the passive visual system in the CIRSSE robotics testbed, research is being conducted in active sensing techniques. This report is description of the research associated with the testbed's laser scanner and its application as an active sensing device. The report is comprised of five major topics. First is a brief description of the CIRSSE visual system and a summary of the active sensing research that has been conducted up to this point. Second, some of the methods currently used to calibrate CIRSSE's laser scanner are described as well as an appraisal of the effectiveness of these methods. Third, is a discussion of how the laser scanner can be employed in concert with a camera to provide a three dimensional point estimation capability. Fourth, there is a description of methods that can be used to detect the presence of the laser beam in a cluttered camera image. Finally, there is a summary of the current state of this research and a description of research planned for the future.

  17. Distributed fiber optical HC leakage and pH sensing techniques for implementation into smart structures

    NASA Astrophysics Data System (ADS)

    Buerck, Jochen M.; Vogel, Bernhard H.; Roth, Siegmar; Ebrahimi, Sasan; Kraemer, Karl

    2004-07-01

    Interaction of target molecules with the evanescent wave of light guided in optical fibers is among the most promising sensing schemes for building up smart chemical sensor technologies. If the technique of optical time domain reflectometry (OTDR) is combined with silicone-clad quartz glass fibers distributed chemical sensing is possible. Hydrocarbon (HC) detection and location is done by automated identification of the position of the corresponding step drop (light loss) in the backscatter signal induced by local refractive index increase in the silicone cladding due to a penetrating HC compound. A commercially available mini-OTDR was adapted to sensing fibers of up to nearly 2-kilometer length and location of typical HC fuels could be demonstrated. The instrument is applicable for fuel leakage monitoring in large technical installations such as tanks or pipelines with spatial resolution down to 1 m. A similar technique using measurements in the Vis spectral range is being developed for health monitoring of large structures, e.g., for early detection of corrosion caused by water ingress and pH changes in reinforced concrete. Here, a pH indicator dye and a phase transfer reagent are immobilized in the originally hydrophobic fiber cladding, leading to a pH induced absorption increase and a step drop signal in the backscatter curve. The configuration of the distributed sensing cables, the instrumental setups, and examples for HC and pH sensing are presented.

  18. Demonstration of distributed fiber-optic temperature sensing with PM fiber using polarization crosstalk analysis technique

    NASA Astrophysics Data System (ADS)

    Su, Hongxin; Zhao, Ziwei; Feng, Ting; Ding, Dongliang; Li, Zhihong; Yao, X. Steve

    2016-11-01

    Polarization crosstalk is a phenomenon that the powers of two orthogonal polarization modes propagating in a polarization maintaining (PM) fiber couple into each other. Because there is certain mathematical relationship between the polarization crosstalk signals and external perturbations such as stress and temperature variations, stress and temperature sensing in PM fiber can be simultaneously achieved by measuring the strengths and locations of polarization crosstalk signals. In this paper, we report what we believe the first distributed temperature sensing demonstration using polarization crosstalk analysis in PM fibers. Firstly, by measuring the spacing changes between two crosstalk peaks at different fiber length locations, we obtained the temperature sensing coefficient (TSC) of approximately -0.73 μm/(°C•m), which means that the spacing between two crosstalk peaks induced at two locations changes by 0.73 μm when the temperature changes by 1 °C over a fiber length of 1 meter. Secondly, in order to bring different temperature values at different axial locations along a PM fiber to verify the distributed temperature sensing, four heating-strips are used to heat different fiber sections of the PM fiber under test, and the temperatures measured by the proposed fiber sensing method according to the obtained TSC are almost consistent with those of heating-strips measured by a thermoelectric thermometer. As a new type of distributed fiber temperature sensing technique, we believe that our method will find broad applications in the near future.

  19. Depth sensing technique using time-to-peak of anode signal in CZT detectors

    NASA Astrophysics Data System (ADS)

    Fu, Jianqiang; Li, Yulan; Zhang, Lan; Li, Yuanjing; Niu, Libo; Wang, Yiming; Liu, Yilin; Li, Jun; Du, Yingshuai; Zhang, Wei; Liu, Yanqing

    2015-10-01

    This paper presents a depth sensing technique implemented on the CZT detectors, which uses the amplitude and the time-to-peak of the anode signal to reconstruct the depth of interaction and the initial deposited energy. The principle and procedure of the reconstruction are described in detail. The feasibility of this technique implemented on a Pixel CZT detector was investigated through simulations and a prototype was fabricated for an experimental test. The experimental results demonstrated the effectiveness of this technique. Depth indexes reconstructed by time-to-peak were in agreement with depth sensing by the C/A ratio, and the performance of the reconstructed spectrum improved obviously. Extensive investigation showed that it is feasible to extend this technique to Strengthened Electric Field Line Anode (SEFLA) detectors. Although the depth sensing had some limitation in practical application due to the non-uniform electric field, energy resolution was significantly improved from 3.2% (FWHM@662 keV) to 1.7%. Efforts will be made to apply this technique on the portable spectrometric systems based on SEFLA detectors.

  20. Novel technique for distributed fibre sensing based on coherent Rayleigh scattering measurements of birefringence

    NASA Astrophysics Data System (ADS)

    Lu, Xin; Soto, Marcelo A.; Thévenaz, Luc

    2016-05-01

    A novel distributed fibre sensing technique is described and experimentally validated, based on birefringence measurements using coherent Rayleigh scattering. It natively provides distributed measurements of temperature and strain with more than an order of magnitude higher sensitivity than Brillouin sensing, and requiring access to a single fibre-end. Unlike the traditional Rayleigh-based coherent optical time-domain reflectometry, this new method provides absolute measurements of the measurand and may lead to a robust discrimination between temperature and strain in combination with another technique. Since birefringence is purposely induced in the fibre by design, large degrees of freedom are offered to optimize and scale the sensitivity to a given quantity. The technique has been validated in 2 radically different types of birefringent fibres - elliptical-core and Panda polarization-maintaining fibres - with a good repeatability.

  1. Small molecule-sensing strategy and techniques for understanding the functionality of green tea.

    PubMed

    Fujimura, Yoshinori

    2015-01-01

    Various low-molecular-weight phytochemicals in green tea (Camellia sinensis L.), especially (-)-epigallocatechin-3-O-gallate (EGCG), are known to be involved in health promotion and disease risk reduction. However, the underlying mechanism has remained elusive because of the absence of an analytical technique that can easily detect the precise behavior of such a small molecule. Recently, we have identified a cell-surface EGCG-sensing receptor and the related signaling molecules that control the physiological functions of EGCG. We also developed a novel in situ label-free imaging technique for visualizing spatially resolved biotransformations based on simultaneous mapping of EGCG and its phase II metabolites. Furthermore, we established a chemometric method capable of evaluating the functionality of multicomponent green tea extracts by focusing on their compositional balances. This review highlights our proposed small molecule-sensing techniques for detecting the complex behavior of green tea components and linking such information to an enhanced understanding of green tea functionality.

  2. Remote sensing techniques for the detection of soil erosion and the identification of soil conservation practices

    NASA Technical Reports Server (NTRS)

    Pelletier, R. E.; Griffin, R. H.

    1985-01-01

    The following paper is a summary of a number of techniques initiated under the AgRISTARS (Agriculture and Resources Inventory Surveys Through Aerospace Remote Sensing) project for the detection of soil degradation caused by water erosion and the identification of soil conservation practices for resource inventories. Discussed are methods to utilize a geographic information system to determine potential soil erosion through a USLE (Universal Soil Loss Equation) model; application of the Kauth-Thomas Transform to detect present erosional status; and the identification of conservation practices through visual interpretation and a variety of enhancement procedures applied to digital remotely sensed data.

  3. Remote sensing techniques for the detection of soil erosion and the identification of soil conservation practices

    NASA Technical Reports Server (NTRS)

    Pelletier, R. E.; Griffin, R. H.

    1985-01-01

    The following paper is a summary of a number of techniques initiated under the AgRISTARS (Agriculture and Resources Inventory Surveys Through Aerospace Remote Sensing) project for the detection of soil degradation caused by water erosion and the identification of soil conservation practices for resource inventories. Discussed are methods to utilize a geographic information system to determine potential soil erosion through a USLE (Universal Soil Loss Equation) model; application of the Kauth-Thomas Transform to detect present erosional status; and the identification of conservation practices through visual interpretation and a variety of enhancement procedures applied to digital remotely sensed data.

  4. Classification of remotely sensed data using OCR-inspired neural network techniques. [Optical Character Recognition

    NASA Technical Reports Server (NTRS)

    Kiang, Richard K.

    1992-01-01

    Neural networks have been applied to classifications of remotely sensed data with some success. To improve the performance of this approach, an examination was made of how neural networks are applied to the optical character recognition (OCR) of handwritten digits and letters. A three-layer, feedforward network, along with techniques adopted from OCR, was used to classify Landsat-4 Thematic Mapper data. Good results were obtained. To overcome the difficulties that are characteristic of remote sensing applications and to attain significant improvements in classification accuracy, a special network architecture may be required.

  5. Classification of remotely sensed data using OCR-inspired neural network techniques. [Optical Character Recognition

    NASA Technical Reports Server (NTRS)

    Kiang, Richard K.

    1992-01-01

    Neural networks have been applied to classifications of remotely sensed data with some success. To improve the performance of this approach, an examination was made of how neural networks are applied to the optical character recognition (OCR) of handwritten digits and letters. A three-layer, feedforward network, along with techniques adopted from OCR, was used to classify Landsat-4 Thematic Mapper data. Good results were obtained. To overcome the difficulties that are characteristic of remote sensing applications and to attain significant improvements in classification accuracy, a special network architecture may be required.

  6. Current achievements of nanoparticle applications in developing optical sensing and imaging techniques

    NASA Astrophysics Data System (ADS)

    Choi, Jong-ryul; Shin, Dong-Myeong; Song, Hyerin; Lee, Donghoon; Kim, Kyujung

    2016-11-01

    Metallic nanostructures have recently been demonstrated to improve the performance of optical sensing and imaging techniques due to their remarkable localization capability of electromagnetic fields. Particularly, the zero-dimensional nanostructure, commonly called a nanoparticle, is a promising component for optical measurement systems due to its attractive features, e.g., ease of fabrication, capability of surface modification and relatively high biocompatibility. This review summarizes the work to date on metallic nanoparticles for optical sensing and imaging applications, starting with the theoretical backgrounds of plasmonic effects in nanoparticles and moving through the applications in Raman spectroscopy and fluorescence biosensors. Various efforts for enhancing the sensitivity, selectivity and biocompatibility are summarized, and the future outlooks for this field are discussed. Convergent studies in optical sensing and imaging have been emerging field for the development of medical applications, including clinical diagnosis and therapeutic applications.

  7. Development and Experimental Verification of Key Techniques to Validate Remote Sensing Products

    NASA Astrophysics Data System (ADS)

    Li, X.; Wang, S. G.; Ge, Y.; Jin, R.; Liu, S. M.; Ma, M. G.; Shi, W. Z.; Li, R. X.; Liu, Q. H.

    2013-05-01

    Validation of remote sensing land products is a fundamental issue for Earth observation. Ministry of Science and Technology of the People's Republic of China (MOST) has launched a high-tech R&D Program named `Development and experimental verification of key techniques to validate remote sensing products' in 2011. This paper introduces the background, scientific objectives, research contents of this project and research result already achieved. The objectives of this project include (1) to build a technical specification for the validation of remote sensing products; (2) to investigate the performance, we will carry out a comprehensive remote sensing experiment on satellite - aircraft - ground truth and then modify Step 1 until reach the predefined requirement; (3) to establish a validation network of China for remote sensing products. In summer 2012, with support of the Heihe Watershed Allied Telemetry Experimental Research (HiWATER), field observations have been successfully conducted in the central stream of the Heihe River Basin, a typical inland river basin in northwest China. A flux observation matrix composed of eddy covariance (EC) and large aperture scintillometer (LAS), in addition to a densely distributed eco-hydrological wireless sensor network have been established to capture multi-scale heterogeneities of evapotranspiration (ET), leaf area index (LAI), soil moisture and temperature. Airborne missions have been flown with the payloads of imaging spectrometer, light detection and ranging (LiDAR), infrared thermal imager and microwave radiometer that provide various scales of aerial remote sensing observations. Satellite images with high resolution have been collected and pre-processed, e.g. PROBA-CHRIS and TerraSAR-X. Simultaneously, ground measurements have been conducted over specific sampling plots and transects to obtain validation data sets. With this setup complex problems are addressed, e.g. heterogeneity, scaling, uncertainty, and eventually to

  8. Three-Dimensional Inverse Transport Solver Based on Compressive Sensing Technique

    NASA Astrophysics Data System (ADS)

    Cheng, Yuxiong; Wu, Hongchun; Cao, Liangzhi; Zheng, Youqi

    2013-09-01

    According to the direct exposure measurements from flash radiographic image, a compressive sensing-based method for three-dimensional inverse transport problem is presented. The linear absorption coefficients and interface locations of objects are reconstructed directly at the same time. It is always very expensive to obtain enough measurements. With limited measurements, compressive sensing sparse reconstruction technique orthogonal matching pursuit is applied to obtain the sparse coefficients by solving an optimization problem. A three-dimensional inverse transport solver is developed based on a compressive sensing-based technique. There are three features in this solver: (1) AutoCAD is employed as a geometry preprocessor due to its powerful capacity in graphic. (2) The forward projection matrix rather than Gauss matrix is constructed by the visualization tool generator. (3) Fourier transform and Daubechies wavelet transform are adopted to convert an underdetermined system to a well-posed system in the algorithm. Simulations are performed and numerical results in pseudo-sine absorption problem, two-cube problem and two-cylinder problem when using compressive sensing-based solver agree well with the reference value.

  9. High-accuracy current sensing circuit with current compensation technique for buck-boost converter

    NASA Astrophysics Data System (ADS)

    Rao, Yuan; Deng, Wan-Ling; Huang, Jun-Kai

    2015-03-01

    A novel on-chip current sensing circuit with current compensation technique suitable for buck-boost converter is presented in this article. The proposed technique can sense the full-range inductor current with high accuracy and high speed. It is mainly based on matched current mirror and does not require a large proportion of aspect ratio between the powerFET and the senseFET, thus it reduces the complexity of circuit design and the layout mismatch issue without decreasing the power efficiency. The circuit is fabricated with TSMC 0.25 µm 2P5M mixed-signal process. Simulation results show that the buck-boost converter can be operated at 200 kHz to 4 MHz switching frequency with an input voltage from 2.8 to 4.7 V. The output voltage is 3.6 V, and the maximum accuracy for both high and low side sensing current reaches 99% within the load current ranging from 200 to 600 mA.

  10. A novel self-sensing technique for tapping-mode atomic force microscopy

    SciTech Connect

    Ruppert, Michael G.; Moheimani, S. O. Reza

    2013-12-15

    This work proposes a novel self-sensing tapping-mode atomic force microscopy operation utilizing charge measurement. A microcantilever coated with a single piezoelectric layer is simultaneously used for actuation and deflection sensing. The cantilever can be batch fabricated with existing micro electro mechanical system processes. The setup enables the omission of the optical beam deflection technique which is commonly used to measure the cantilever oscillation amplitude. Due to the high amount of capacitive feedthrough in the measured charge signal, a feedforward control technique is employed to increase the dynamic range from less than 1 dB to approximately 35 dB. Experiments show that the conditioned charge signal achieves excellent signal-to-noise ratio and can therefore be used as a feedback signal for atomic force microscopy imaging.

  11. An optical fiber sensing technique for temperature distribution measurements in microwave heating

    NASA Astrophysics Data System (ADS)

    Wada, Daichi; Sugiyama, Jun-ichi; Zushi, Hiroaki; Murayama, Hideaki

    2015-08-01

    We introduce an optical fiber sensing technique that can measure the temperature distributions along a fiber during microwave heating. We used a long-length fiber Bragg grating (FBG) as an electromagnetic-immune sensor and interrogated temperature distributions along the FBG by an optical frequency domain reflectometry. Water in a glass tube with a length of 820 mm was heated in a microwave oven, and its temperature distribution along the glass tube was measured using the sensing system. The temperature distribution was obtained in 5 mm intervals. Infrared radiometry was also used to compare the temperature measurement results. Time and spatial variations of the temperature distribution profiles were monitored for several microwave input powers. The results clearly depict inhomogeneous temperature profiles. The applicability and effectiveness of the optical fiber distributed measurement technique in microwave heating are demonstrated.

  12. Sensing Applied Load and Damage Effects in Composites with Nondestructive Techniques

    DTIC Science & Technology

    2017-05-01

    and correlated . This report summarizes experimental setups involving the various NDE methods and technics and provide results on the effects of load... Correlating and validating NDE strategies for sensing damage and operational effects on composite materials will add to the knowledge of composites and...multiple NDE Approved for public release; distribution is unlimited. 5 techniques are used in this study for mutual correlation and verification

  13. An indirect sensing technique for diesel fuel quantity control. Progress report, April 1--June 30, 1998

    SciTech Connect

    MacCarley, C.A.

    1998-08-31

    This reports on a project to develop an indirect sensing technique for diesel fuel quantity control. Development has continued on a vehicle-installed prototype for EPA certification and demonstration. Focus of development is on the use of this technology for retrofitting existing diesel vehicles to reduce emissions rather than exclusively upon deployment in the OEM market. Technical obstacles that have been encountered and their solutions and remaining project tasks are described.

  14. Optimization of the polarization remote-sensing techniques of the ocean

    NASA Astrophysics Data System (ADS)

    Krotkov, Nickolay A.; Kondranin, Timofei V.; Vasilkov, Alexander P.

    1992-12-01

    A numerical code has been developed to calculate Stokes parameters of the visible solar radiation, scattered in the atmosphere-ocean system. Mathematical modeling is used to examine spectral and angular (azimuth and zenith angle) variations of degree of polarization at sea level and at different heights in the atmosphere above the sea surface. On the basis of a developed computer code the efficiency of the polarization measurements for different optical passive remote sensing techniques of the ocean has been investigated. For the passive spectral measurements of the water bio-productivity (chlorophyll-a, dissolved organic matter, concentration of suspended particles) the polarizer can improve signal-to-background ratio. The magnitude of this effect and optimum direction of the polarizer depend upon height, viewing direction, and solar zenith angle. Within the framework of polarization remote sensing technique the influence of the observation height and viewing direction on the results of water turbidity measurements is investigated. Optimal viewing directions in such polarization passive remote sensing technique are discussed.

  15. Quantitative and qualitative sensing techniques for biogenic volatile organic compounds and their oxidation products.

    PubMed

    Kim, Saewung; Guenther, Alex; Apel, Eric

    2013-07-01

    The physiological production mechanisms of some of the organics in plants, commonly known as biogenic volatile organic compounds (BVOCs), have been known for more than a century. Some BVOCs are emitted to the atmosphere and play a significant role in tropospheric photochemistry especially in ozone and secondary organic aerosol (SOA) productions as a result of interplays between BVOCs and atmospheric radicals such as hydroxyl radical (OH), ozone (O3) and NOX (NO + NO2). These findings have been drawn from comprehensive analysis of numerous field and laboratory studies that have characterized the ambient distribution of BVOCs and their oxidation products, and reaction kinetics between BVOCs and atmospheric oxidants. These investigations are limited by the capacity for identifying and quantifying these compounds. This review highlights the major analytical techniques that have been used to observe BVOCs and their oxidation products such as gas chromatography, mass spectrometry with hard and soft ionization methods, and optical techniques from laser induced fluorescence (LIF) to remote sensing. In addition, we discuss how new analytical techniques can advance our understanding of BVOC photochemical processes. The principles, advantages, and drawbacks of the analytical techniques are discussed along with specific examples of how the techniques were applied in field and laboratory measurements. Since a number of thorough review papers for each specific analytical technique are available, readers are referred to these publications rather than providing thorough descriptions of each technique. Therefore, the aim of this review is for readers to grasp the advantages and disadvantages of various sensing techniques for BVOCs and their oxidation products and to provide guidance for choosing the optimal technique for a specific research task.

  16. High-quality correspondence imaging based on sorting and compressive sensing technique

    NASA Astrophysics Data System (ADS)

    Wu, Heng; Zhang, Xianmin; Gan, Jinqiang; Luo, Chunling; Ge, Peng

    2016-11-01

    We propose a high-quality imaging method based on correspondence imaging (CI) using a sorting and compressive sensing (CS) technique. Unlike the traditional CI, the positive and negative (PN) subsets are created by a sorting method, and the image of an object is then recovered from the PN subsets using a CS technique. We compare the performance of the proposed method with different ghost imaging (GI) algorithms using the data from a single-detector computational GI system. The results demonstrate that our method enjoys excellent imaging and anti-interference capabilities, and can further reduce the measurement numbers compared with the direct use of CS in GI.

  17. A review on reflective remote sensing and data assimilation techniques for enhanced agroecosystem modeling

    NASA Astrophysics Data System (ADS)

    Dorigo, W. A.; Zurita-Milla, R.; de Wit, A. J. W.; Brazile, J.; Singh, R.; Schaepman, M. E.

    2007-05-01

    During the last 50 years, the management of agroecosystems has been undergoing major changes to meet the growing demand for food, timber, fibre and fuel. As a result of this intensified use, the ecological status of many agroecosystems has been severely deteriorated. Modeling the behavior of agroecosystems is, therefore, of great help since it allows the definition of management strategies that maximize (crop) production while minimizing the environmental impacts. Remote sensing can support such modeling by offering information on the spatial and temporal variation of important canopy state variables which would be very difficult to obtain otherwise. In this paper, we present an overview of different methods that can be used to derive biophysical and biochemical canopy state variables from optical remote sensing data in the VNIR-SWIR regions. The overview is based on an extensive literature review where both statistical-empirical and physically based methods are discussed. Subsequently, the prevailing techniques of assimilating remote sensing data into agroecosystem models are outlined. The increasing complexity of data assimilation methods and of models describing agroecosystem functioning has significantly increased computational demands. For this reason, we include a short section on the potential of parallel processing to deal with the complex and computationally intensive algorithms described in the preceding sections. The studied literature reveals that many valuable techniques have been developed both for the retrieval of canopy state variables from reflective remote sensing data as for assimilating the retrieved variables in agroecosystem models. However, for agroecosystem modeling and remote sensing data assimilation to be commonly employed on a global operational basis, emphasis will have to be put on bridging the mismatch between data availability and accuracy on one hand, and model and user requirements on the other. This could be achieved by

  18. Post-coronagraphic tip-tilt sensing for vortex phase masks: The QACITS technique

    NASA Astrophysics Data System (ADS)

    Huby, E.; Baudoz, P.; Mawet, D.; Absil, O.

    2015-12-01

    Context. Small inner working angle coronagraphs, such as the vortex phase mask, are essential to exploit the full potential of ground-based telescopes in the context of exoplanet detection and characterization. However, the drawback of this attractive feature is a high sensitivity to pointing errors, which degrades the performance of the coronagraph. Aims: We propose a tip-tilt retrieval technique based on the analysis of the final coronagraphic image, hereafter called Quadrant Analysis of Coronagraphic Images for Tip-tilt Sensing (QACITS). Methods: Under the assumption of small phase aberrations, we show that the behavior of the vortex phase mask can be simply described from the entrance pupil to the Lyot stop plane with Zernike polynomials. This convenient formalism is used to establish the theoretical basis of the QACITS technique. We performed simulations to demonstrate the validity and limits of the technique, including the case of a centrally obstructed pupil. Results: The QACITS technique principle is validated with experimental results in the case of an unobstructed circular aperture, as well as simulations in presence of a central obstruction. The typical configuration of the Keck telescope (24% central obstruction) has been simulated with additional high order aberrations. In these conditions, our simulations show that the QACITS technique is still adapted to centrally obstructed pupils and performs tip-tilt retrieval with a precision of 5 × 10-2λ/D when wavefront errors amount to λ/ 14 rms and 10-2λ/D for λ/ 70 rms errors (with λ the wavelength and D the pupil diameter). Conclusions: We have developed and demonstrated a tip-tilt sensing technique for vortex coronagraphs. The implementation of the QACITS technique is based on the analysis of the scientific image and does not require any modification of the original setup. Current facilities equipped with a vortex phase mask can thus directly benefit from this technique to improve the contrast

  19. Estimating Crop Growth Stage by Combining Meteorological and Remote Sensing Based Techniques

    NASA Astrophysics Data System (ADS)

    Champagne, C.; Alavi-Shoushtari, N.; Davidson, A. M.; Chipanshi, A.; Zhang, Y.; Shang, J.

    2016-12-01

    Estimations of seeding, harvest and phenological growth stage of crops are important sources of information for monitoring crop progress and crop yield forecasting. Growth stage has been traditionally estimated at the regional level through surveys, which rely on field staff to collect the information. Automated techniques to estimate growth stage have included agrometeorological approaches that use temperature and day length information to estimate accumulated heat and photoperiod, with thresholds used to determine when these stages are most likely. These approaches however, are crop and hybrid dependent, and can give widely varying results depending on the method used, particularly if the seeding date is unknown. Methods to estimate growth stage from remote sensing have progressed greatly in the past decade, with time series information from the Normalized Difference Vegetation Index (NDVI) the most common approach. Time series NDVI provide information on growth stage through a variety of techniques, including fitting functions to a series of measured NDVI values or smoothing these values and using thresholds to detect changes in slope that are indicative of rapidly increasing or decreasing `greeness' in the vegetation cover. The key limitations of these techniques for agriculture are frequent cloud cover in optical data that lead to errors in estimating local features in the time series function, and the incongruity between changes in greenness and traditional agricultural growth stages. There is great potential to combine both meteorological approaches and remote sensing to overcome the limitations of each technique. This research will examine the accuracy of both meteorological and remote sensing approaches over several agricultural sites in Canada, and look at the potential to integrate these techniques to provide improved estimates of crop growth stage for common field crops.

  20. Fiber Bragg grating-based wavelength modulation spectroscopy technique for trace gas sensing

    NASA Astrophysics Data System (ADS)

    Tiwari, Shivani; Vasa, Nilesh J.; Srinivasan, Balaji

    2016-04-01

    A novel gas sensing system based on a tunable fiber Bragg grating (FBG) and a Super luminescent light emitting diode (SLED) source is proposed for trace gas sensing. Such a system has been demonstrated for precise detection of acetylene (C2H2) using wavelength modulation spectroscopy technique (WMS) based on modulating the Bragg wavelength of FBG within the width of an absorption line of a target gas. The sensing system has been calibrated against specific gas concentrations (ppm) through controlled experiments and the minimum detectable acetylene (C2H2) gas concentration is experimentally found to be 80 ppm (0.008% by volume). Furthermore, the detection limit of the system is estimated to be limited by the noise floor of our system at 7 ppm (0.0007% by volume). The proposed system provides a relatively inexpensive alternative for trace gas sensing based on a well-established FBG technology. Moreover, the proposed system has tremendous potential for simultaneous detection of multiple species through the use of a cascaded set of carefully chosen FBGs.

  1. Generalized high-spectral-resolution lidar technique with a multimode laser for aerosol remote sensing.

    PubMed

    Cheng, Zhongtao; Liu, Dong; Zhang, Yupeng; Liu, Chong; Bai, Jian; Wang, Dan; Wang, Nanchao; Zhou, Yudi; Luo, Jing; Yang, Yongying; Shen, Yibing; Su, Lin; Yang, Liming

    2017-01-23

    High-spectral-resolution lidar (HSRL) is a powerful tool for atmospheric aerosol remote sensing. The current HSRL technique often requires a single longitudinal mode laser as the transmitter to accomplish the spectral discrimination of the aerosol and molecular scattering conveniently. However, single-mode laser is cumbersome and has very strict requirements for ambient stability, making the HSRL instrument not so robust in many cases. In this paper, a new HSRL concept, called generalized HSRL technique with a multimode laser (MML-gHSRL), is proposed, which can work using a multimode laser. The MML-gHSRL takes advantage of the period characteristic of the spectral function of the interferometric spectral discrimination filter (ISDF) thoroughly. By matching the free spectral range of the ISDF with the mode interval of the multimode laser, fine spectral discrimination for the lidar return from each longitudinal mode can be realized. Two common ISDFs, i.e., the Fabry-Perot interferometer (FPI) and field-widened Michelson interferometer (FWMI), are introduced to develop the MML-gHSRL, and their performance is quantitatively analyzed and compared. The MML-gHSRL is a natural but significant generalization for the current HSRL technique based on the IDSF. It is potential that this technique would be a good entrance to future HSRL developments, especially in airborne and satellite-borne aerosol remote sensing applications.

  2. Shape Sensing Techniques for Continuum Robots in Minimally Invasive Surgery: A Survey.

    PubMed

    Shi, Chaoyang; Luo, Xiongbiao; Qi, Peng; Li, Tianliang; Song, Shuang; Najdovski, Zoran; Fukuda, Toshio; Ren, Hongliang

    2017-08-01

    Continuum robots provide inherent structural compliance with high dexterity to access the surgical target sites along tortuous anatomical paths under constrained environments and enable to perform complex and delicate operations through small incisions in minimally invasive surgery. These advantages enable their broad applications with minimal trauma and make challenging clinical procedures possible with miniaturized instrumentation and high curvilinear access capabilities. However, their inherent deformable designs make it difficult to realize 3-D intraoperative real-time shape sensing to accurately model their shape. Solutions to this limitation can lead themselves to further develop closely associated techniques of closed-loop control, path planning, human-robot interaction, and surgical manipulation safety concerns in minimally invasive surgery. Although extensive model-based research that relies on kinematics and mechanics has been performed, accurate shape sensing of continuum robots remains challenging, particularly in cases of unknown and dynamic payloads. This survey investigates the recent advances in alternative emerging techniques for 3-D shape sensing in this field and focuses on the following categories: fiber-optic-sensor-based, electromagnetic-tracking-based, and intraoperative imaging modality-based shape-reconstruction methods. The limitations of existing technologies and prospects of new technologies are also discussed.

  3. Use of an infrared sensing technique in the regular monitoring of incinerators and a kiln

    NASA Astrophysics Data System (ADS)

    Varrio, Jukka P.; Kesanto, Seppo; Heikkinen, Tapio

    1995-03-01

    Thermal imaging is a promising technology in the field of predictive maintenance. However, the effective use of infrared sensing techniques in predictive maintenance necessitates (1) good preliminary preparations, (2) regular imaging of the targets, (3) an infrared imaging system equipped with a floppy-disk drive, and, (4) an effective computer program for making analyses and drawing conclusions. At present, due to the lack of suitable software, there are not many practical applications of this technique in this field. In this paper, a functioning maintenance program for an industrial plant using a thermal sensing technique is presented. The strategy for constructing this program and the problems involved in this work are introduced. Also the main results, which clearly indicate the usefulness of thermal sensing techniques in predictive maintenance, are presented. This maintenance program has been constructed and been in use in the modern hazardous waste plant, EKOKEM Ltd., for the last two years. This program uses an Inframetrics model 760 infrared thermal imaging radiometer and a Thermonitor thermal image processing program by Thermoteknix Systems Ltd. The maintenance consists of (1) regular thermal imaging of the critical parts of the incinerators and (2) thermal image computer analysis. Also, a large table (arrays of thermal images) illustrating visually the target temperature behavior as a function of time has been constructed. This table together with the data from the computer analysis show both slow and rapid temperature variations clearly. The hot spots and limited hot areas which are indications of abnormal wear, are easily observed in our analyses. There is no way to observe these local hot spots using any other method. Thus unnecessary shutdowns, in some cases, can be prevented.

  4. Guided compressive sensing single-pixel imaging technique based on hierarchical model

    NASA Astrophysics Data System (ADS)

    Peng, Yang; Liu, Yu; Ren, Weiya; Tan, Shuren; Zhang, Maojun

    2016-04-01

    Single-pixel imaging has emerged a decade ago as an imaging technique that exploits the theory of compressive sensing. In this research, the problem of optimizing the measurement matrix in compressive sensing framework was addressed. Thus far, random measurement matrices are widely used because they provide small coherence. However, recent reports claim that measurement matrix can be optimized, thereby improving its performance. Based on such proposition, this study proposed an alternative approach of optimizing the measurement matrix in a hierarchical model. In particular, this study constructed the hierarchical model based on an increasing resolution grade by exploiting the guided information and the adaptive step size method. An image with a demanded resolution was then obtained using the l1-norm method. Subsequently, the performance of the introduced method was verified and compared with those of existing approaches via several experiments. Results of the tests indicated that the reconstruction quality of optimizing the measurement matrix was improved when the proposed method was used.

  5. Novel Technique and Technologies for Active Optical Remote Sensing of Greenhouse Gases

    NASA Technical Reports Server (NTRS)

    Singh, Upendra N.; Refaat, Tamer F.; Petros, Mulugeta

    2017-01-01

    The societal benefits of understanding climate change through identification of global carbon dioxide sources and sinks led to the desired NASA's active sensing of carbon dioxide emissions over nights, days, and seasons (ASCENDS) space-based missions of global carbon dioxide measurements. For more than 15 years, NASA Langley Research Center (LaRC) have developed several carbon dioxide active remote sensors using the differential absorption lidar (DIAL) technique operating at the two-micron wavelength. Currently, an airborne two-micron triple-pulse integrated path differential absorption (IPDA) lidar is under development. This IPDA lidar measures carbon dioxide as well as water vapor, the dominant interfering molecule on carbon dioxide remote sensing. Advancement of this triple-pulse IPDA lidar development is presented.

  6. Multi-Technique Remote-Sensing Observations and Modelling of a Coronal Mass Ejection

    NASA Astrophysics Data System (ADS)

    Hardwick, S. A.; Bisi, M. M.; Davies, J.; Morgan, H.; Fallows, R.; Harrison, R. A.; Xiong, M.; Jensen, E. A.

    2012-12-01

    On 14 November 2011, SDO|AIA observed a filament eruption located around S25 to S30 and extended between W20 and W40 of disc centre. The resulting coronal mass ejection (CME) is studied in detail using radio, white-light, and EUV remote-sensing observations from STEREO, SOHO, SDO, and the new next-generation LOFAR radio telescope system. We present a detailed story of the CME as it travels through the heliosphere with its northern flank travelling in the ecliptic out towards Mars. Various models are fitted to the heliospheric white-light data and different portions of the CME are investigated as they propagate through the inner heliosphere. The validity of each model is discussed. This combination of remote-sensing observational and modelling techniques displays a valid framework for further detailed investigations of CMEs.

  7. Fabricate Optical Microfiber by Using Flame Brushing Technique and Coated with Polymer Polyaniline for Sensing Application

    NASA Astrophysics Data System (ADS)

    Razak, N. A.; Hamida, B. A.; Irawati, N.; Habaebi, M. H.

    2017-06-01

    Adiabaticity is one of the essential criteria in producing good fabricated tapered fibers. Good tapered fibers can be use in sensor application such as humidity sensor, temperature sensor and refractive index sensor. In this paper, good tapering silica fiber is produced by using flame brushing technique and then, the microfiber is coated with polymer Polyaniline (PAni) to sense different type of alcohols with different concentrations. The outcome of this experiment gives excellent repeatability in the detection of alcohol sensing with a sensitivity of 0.1332 μW/% and a resolution of 3.764%. In conclusion, conducting polymer coated optical microfiber sensor for alcohol detection with low cost, effective and simple set-up was successfully achieved in this study.

  8. Measurements of Absorbing Aerosols Using in Situ and Remote Sensing Techniques

    NASA Astrophysics Data System (ADS)

    Martins, J. V.; Martins, J. V.; Kaufman, Y.; Artaxo, P.; Andrea, C.; Yamasoe, M.; Remer, L.

    2001-12-01

    Reliable measurements of light absorption by aerosol particles are essential for an accurate assessment of the climate radiative forcing by aerosol particles. Depending on the absorption properties, the radiative forcing of the aerosols may change from a cooling to a heating effect. New techniques for the remote sensing of aerosol absorption over land and ocean are developed and applied in combination with in situ measurements for validation and addition of complementary information. Spectral measurements show the effects of aerosols on absorption of light from the UV to the near infrared. Depending on particle size and structure, there is a significant absorption component that must be accounted for the radiative forcing in the near infrared. Remote sensing results from MODIS and from the CLAMS field experiment, as well as in situ validation data will be discussed.

  9. Remote sensing and GIS techniques for selecting a sustainable scenario for Lake Koronia, Greece.

    PubMed

    Alexandridis, Thomas K; Takavakoglou, Vasileios; Crisman, Thomas L; Zalidis, George C

    2007-02-01

    During recent decades, Lake Koronia has undergone severe degradation as a result of human activities around the lake and throughout the basin. Surface and groundwater abstraction and pollution from agricultural, industrial, and municipal sources are the major sources of degradation. Planning a restoration project was hampered by lack of sufficient data, with gaps evident in both spatial and temporal dimensions. This study emphasized various remote sensing and geographic information system techniques, such as digital image processing and geographic overlay, to fill gaps using satellite imagery and other spatial environmental, hydrological, and hydrogeological data in the process of planning the restoration of Lake Koronia, following Ramsar guidelines. Current and historical remote sensing data were used to assess the current status and level of degradation, set constraints and define the ideotype for the restoration, and, finally, define and select the best restoration scenario.

  10. Experimental verification of dispersed fringe sensing as a segment phasing technique using the Keck telescope.

    PubMed

    Shi, Fang; Chanan, Gary; Ohara, Catherine; Troy, Mitchell; Redding, David C

    2004-08-10

    Dispersed fringe sensing (DFS) is an efficient and robust method for coarse phasing of segmented primary mirrors (from one quarter of a wavelength to as much as the depth of focus of a single segment, typically several tens of microns). Unlike phasing techniques currently used for ground-based segmented telescopes, DFS does not require the use of edge sensors in order to sense changes in the relative heights of adjacent segments; this makes it particularly well suited for phasing of space-borne segmented telescopes, such as the James Webb Space Telescope. We validate DFS by using it to measure the piston errors of the segments of one of the Keck telescopes. The results agree with those of the Shack-Hartmann-based phasing scheme currently in use at Keck to within 2% over a range of initial piston errors of +/-16 microm.

  11. Research on the demodulation techniques of long-period fiber gratings strain sensing with low cost

    NASA Astrophysics Data System (ADS)

    Wang, Qingwei; Liu, Yueming; Tian, Weijian; Feng, Guilan

    2012-10-01

    The working principle of LPFG(Long-Period Fiber Grating) is based on coupling effect between propagating core-mode and co-propagating cladding-modes. The effective refractive index of cladding-modes could be obviously influenced by the environmental changes resulting in LPFG more sensitive than FBG (Fiber Bragg Grating) in sensing areas, such as temperature, strain, concentration, bending and etc. LPFG should have more potential in the field of sensors compared with FBG. One of the challenges in using LPFG for environmental sensing is how to interrogate the signal from the LPFG transmission spectrum, due to the large spectral range of the resonant dip. Nowadays the application of LPFG is normally limited in signal interrogation of FBG as optical edge filter. The signal interrogation of LPFG itself needs further research. Presently research on signal interrogation of fiber grating focuses on wavelength interrogation. The aim of wavelength interrogation is to get the wavelength shift caused by environmental change. To solve these problems, a kind of strain sensing interrogation technique for LPFG with low-cost based on tunable FBGs has been developed. Comparing with the method using Fabry-Perot cavity, tunable FBGs can lower the cost with the guarantee of sensing precision. The cost is further lowered without using expensive optical instruments such as optical switch. The problem of temperature cross-sensitivity was solved by using reference gratings. An experiment was performed to demonstrate the interrogation system. And in the experiment, the sensing signal of LPFG applied 0-1300μɛ was successfully interrogated. The results of the interrogation system and OSA are similar.

  12. An improved dual-frequency technique for the remote sensing of ocean currents and wave spectra

    NASA Technical Reports Server (NTRS)

    Schuler, D. L.; Eng, W. P.

    1984-01-01

    A two frequency microwave radar technique for the remote sensing of directional ocean wave spectra and surface currents is investigated. This technique is conceptually attractive because its operational physical principle involves a spatial electromagnetic scattering resonance with a single, but selectable, long gravity wave. Multiplexing of signals having different spacing of the two transmitted frequencies allows measurements of the entire long wave ocean spectrum to be carried out. A new scatterometer is developed and experimentally tested which is capable of making measurements having much larger signal/background values than previously possible. This instrument couples the resonance technique with coherent, frequency agility radar capabilities. This scatterometer is presently configured for supporting a program of surface current measurements.

  13. A Remote Sensing Technique For Combustion Gas Temperature Measurement In Black Liquor Recovery Boilers

    NASA Astrophysics Data System (ADS)

    Charagundla, S. R.; Semerjian, H. G.

    1986-10-01

    A remote sensing technique, based on the principles of emission spectroscopy, is being developed for temperature measurements in black liquor recovery boilers. Several tests have been carried out, both in the laboratory and at a number of recovery boilers, to characterize the emission spectra in the wavelength range of 300 nm to 800 nm. These tests have pointed out the potential for temperature measurements using the line intensity ratio technique based on a pair of emission lines at 404.4 nm and 766.5 nm observed in the recovery boiler combustion zone; these emission lines are due to potassium, a common constituent found in all the black liquors. Accordingly, a fiber optics based four-color system has been developed. This in-situ, nonintrusive temperature measurement technique, together with some of the more recent results, is described in this paper.

  14. Validation of attitude/deformation sensing techniques for space flexible manipulators

    NASA Astrophysics Data System (ADS)

    Gasbarri, Paolo; Palmerini, Giovanni B.; Coppotelli, Giuliano; Toglia, Chiara

    2009-01-01

    This paper proposes an approach that makes use of two different techniques to sense and identify both the rigid attitude motion and the flexible dynamics of a manipulator. With the first technique, an accurate attitude motion determination, based on the use of a global navigation satellite systems (GNSS) signals, is performed. For this purpose, some antennas are placed on the manipulator in order to obtain the observable phase of the GNSS signal. The second technique, based on the use of accelerometer sensors, is used in order to identify the dynamic signature during the motion of the flexible link. Specifically, the modal parameters are estimated using data recorded from accelerometers, conveniently placed on the structure, by means of an output-only based approach. The developed algorithms used for both the attitude estimation and the output-only modal analysis are validated by experimental activities carried out on an in-house testbed representing a two flexible arm manipulator.

  15. Dual measurement self-sensing technique of NiTi actuators for use in robust control

    NASA Astrophysics Data System (ADS)

    Gurley, Austin; Lambert, Tyler Ross; Beale, David; Broughton, Royall

    2017-10-01

    Using a shape memory alloy actuator as both an actuator and a sensor provides huge benefits in cost reduction and miniaturization of robotic devices. Despite much effort, reliable and robust self-sensing (using the actuator as a position sensor) had not been achieved for general temperature, loading, hysteresis path, and fatigue conditions. Prior research has sought to model the intricacies of the electrical resistivity changes within the NiTi material. However, for the models to be solvable, nearly every previous technique only models the actuator within very specific boundary conditions. Here, we measure both the voltage across the entire NiTi wire and of a fixed-length segment of it; these dual measurements allow direct calculation of the actuator length without a material model. We review previous self-sensing literature, illustrate the mechanism design that makes the new technique possible, and use the dual measurement technique to determine the length of a single straight wire actuator under controlled conditions. This robust measurement can be used for feedback control in unknown ambient and loading conditions.

  16. Mapping Glauconite Unites with Using Remote Sensing Techniques in North East of Iran

    NASA Astrophysics Data System (ADS)

    Ahmadirouhani, R.; Samiee, S.

    2014-10-01

    Glauconite is a greenish ferric-iron silicate mineral with micaceous structure, characteristically formed in shallow marine environments. Glauconite has been used as a pigmentation agent for oil paint, contaminants remover in environmental studies and a source of potassium in plant fertilizers, and other industries. Koppeh-dagh basin is extended in Iran, Afghanistan and Turkmenistan countries and Glauconite units exist in this basin. In this research for enhancing and mapping glauconitic units in Koppeh-dagh structural zone in north east of Iran, remote sensing techniques such as Spectral Angle Mapper classification (SAM), band ratio and band composition methods on SPOT, ASTER and Landsat data in 3 steps were applied.

  17. Reliable Welding of HSLA Steels by Square Wave Pulsing Using an Advanced Sensing (EDAP) Technique.

    DTIC Science & Technology

    1986-04-30

    situation is the result of welding on A710 steel . (A similar effect on welding on HY80 ?) The following is offered by Woods and Milner (Ref. 12): "The...AD-R69 762 RELIABLE MELDING OF HSLA STEELS BY SQUARE MAVE PULSING 1/2 USING AN ADV NCED.. (U) APPLIED FUSION TECHNOLOGIES INC FORT COLLINS CO C...6 p . 0 Report 0001 AZ AD-A 168 762 I "RELIABLE WELDING OF HSLA STEELS BY SQUARE WAVE PULSING USING AN ADVANCED SENSING (EDAP) TECHNIQUE- Preliminary

  18. Techniques for Remote Sensing of Ionospheric Electron Density from a Spacecraft.

    DTIC Science & Technology

    1981-08-05

    J FULKS . T E OLD F19628-BO-C-O169 UNCLASSIFIED MRC-R-66B AFGL-TR-81-0331 t4. IIIIIIIIIIIIIIfflfflf II l lllhh~lflfll IIIEIIEEEEEEEEI 11111Al L~12 im...SPACECRAFT Joseph A. Ball Gordon J. Fulks Thomas E. Old William R. Wortman Mission Research Corporation 735 State Street P.O. Drawer 719 Santa Barbara...TECHNIQUES FOR REMOTE SENSING OF IONOSPHERIC ELECTRON DENSITY F-ETC(U) AUG 81 J5 A BALL, 6 J FULKS , T E OLD F19628-60-C-0169 UNCLASSIFIED NRC-R-GAB AFGL-TR

  19. Use of multiple-stage remote sensing techniques to develop forest stocking equations

    NASA Technical Reports Server (NTRS)

    Bisson, H. R.; Rasmussen, W. O.; Ffolliott, P. F.

    1975-01-01

    Portions of a forest supporting density levels that affect natural resource yields must be quantified to estimate the operational feasibility of a proposed management system. Estimates of average parameters do not necessarily provide complete knowledge, particularly with frequently skewed forest parameters. Instead, another statistic, the portion of a forest supporting minimum density levels would be useful to set realistic limits to the implementation of management systems and to establish priorities for operational programs. Such a statistic can be obtained from solutions of forest stocking equations generated by applications of multiple-stage remote sensing techniques.

  20. Equipment and techniques for low-altitude aerial sensing of water-vapor concentration and movement

    USGS Publications Warehouse

    Howell, R.L.

    1969-01-01

    Progress in the development of equipment and techniques for making rapid measurements of moisture movement through the atmosphere over a large area is described. Airborne sensing elements measure relative humidity, temperature, and air currents. These data are telemetered to a ground-based station and recorded. A radar unit tracks the aircraft and electronically plots its position on a base map of the area being studied. Thus the distribution of atmospheric conditions can be directly related to the underlying terrain and vegetation features. ?? 1969 American Elsevier Publishing Company, Inc.

  1. Sensing and identification of carbon monoxide using carbon films fabricated by methane arc discharge decomposition technique

    PubMed Central

    2014-01-01

    Carbonaceous materials have recently received attention in electronic applications and measurement systems. In this work, we demonstrate the electrical behavior of carbon films fabricated by methane arc discharge decomposition technique. The current-voltage (I-V) characteristics of carbon films are investigated in the presence and absence of gas. The experiment reveals that the current passing through the carbon films increases when the concentration of CO2 gas is increased from 200 to 800 ppm. This phenomenon which is a result of conductance changes can be employed in sensing applications such as gas sensors. PMID:25177219

  2. A satellite remote-sensing technique for geological horizon structure mapping

    SciTech Connect

    Fraser, A.J.; Huggins, P.; Cleverley, P.H.; Rees, J.L.

    1995-12-31

    A Satellite Remote Sensing technique is demonstrated which provides accurate and cost effective near-surface geological structure data. In the exploration phase the technique enables the rapid and inexpensive screening of open licences and the targeting of seismic acquisition, particularly important in terrains of difficult data acquisition. This paper describes the satellite data used, the technique of horizon surface data extraction and the analysis of a case study from Yemen. Landsat Thematic Mapper (TM) data and a high resolution digital elevation model (DEM), generated from stereo SPOT panchromatic images, are used in conjunction to identify a number of outcropping horizons and map their spatial position and height. Geological contacts are identified and digitised from the Landsat TM data and the elevations of these points taken from the digital elevation data. The extracted x,y,z co-ordinates are then gridded to construct a horizon structure map. The technique is applied to an area of central Yemen which is characterised by a near-surface {open_quote}layer cake{close_quote} geological structure in an extremely low dipping terrain (Less than 1{degrees}). The remote sensing interpretation is validated by comparison with 2D seismic across the area. Regional flexural structures with bed dips of as little as 0.25{degrees} can be mapped. Trend analysis and residual calculations on the horizon structure map show the techniques ability to identify and quantify horizon deformation related to faulting. Surface geological structure was successfully interpolated into the subsurface indicating potential fault closure at reservoir target depths.

  3. Geographic techniques and recent applications of remote sensing to landscape-water quality studies

    USGS Publications Warehouse

    Griffith, J.A.

    2002-01-01

    This article overviews recent advances in studies of landscape-water quality relationships using remote sensing techniques. With the increasing feasibility of using remotely-sensed data, landscape-water quality studies can now be more easily performed on regional, multi-state scales. The traditional method of relating land use and land cover to water quality has been extended to include landscape pattern and other landscape information derived from satellite data. Three items are focused on in this article: 1) the increasing recognition of the importance of larger-scale studies of regional water quality that require a landscape perspective; 2) the increasing importance of remotely sensed data, such as the imagery-derived normalized difference vegetation index (NDVI) and vegetation phenological metrics derived from time-series NDVI data; and 3) landscape pattern. In some studies, using landscape pattern metrics explained some of the variation in water quality not explained by land use/cover. However, in some other studies, the NDVI metrics were even more highly correlated to certain water quality parameters than either landscape pattern metrics or land use/cover proportions. Although studies relating landscape pattern metrics to water quality have had mixed results, this recent body of work applying these landscape measures and satellite-derived metrics to water quality analysis has demonstrated their potential usefulness in monitoring watershed conditions across large regions.

  4. Integrating remote sensing techniques at Cuprite, Nevada: AVIRIS, Thematic Mapper, and field spectroscopy

    NASA Technical Reports Server (NTRS)

    Hill, Bradley; Nash, Greg; Ridd, Merrill; Hauff, Phoebe L.; Ebel, Phil

    1992-01-01

    The Cuprite mining district in southwestern Nevada has become a test site for remote sensing studies with numerous airborne scanners and ground sensor data sets collected over the past fifteen years. Structurally, the Cuprite region can be divided into two areas with slightly different alteration and mineralogy. These zones lie on either side of a postulated low-angle structural discontinuity that strikes nearly parallel to US Route 95. Hydrothermal alternation at Cuprite was classified into three major zones: silicified, opalized, and argillized. These alteration types form a bulls-eye pattern east of the highway and are more linear on the west side of the highway making a striking contrast from the air and the imagery. Cuprite is therefore an ideal location for remote sensing research as it exhibits easily identified hydrothermal zoning, is relatively devoid of vegetation, and contains a distinctive spectrally diagnostic mineral suite including the ammonium feldspar buddingtonite, several types of alunite, different jarosites, illite, kaolinite, smectite, dickite, and opal. This present study brings a new dimension to these previous remote sensing and ground data sets compiled for Cuprite. The development of a higher resolution field spectrometer now provides the capability to combine extensive in-situ mineralogical data with a new geologic field survey and detailed Airborne Visible/Infrared Imaging Spectrometers (AVIRIS) images. The various data collection methods and the refinement of the integrated techniques are discussed.

  5. Utilizing the cochlea as a bio-inspired compressive sensing technique

    NASA Astrophysics Data System (ADS)

    Peckens, C. A.; Lynch, J. P.

    2013-10-01

    Structural monitoring for civil infrastructure is a rapidly developing field that has made significant advancements over the last decade. However, a number of performance bottlenecks remain including challenges with cost-effectively scaling monitoring systems up to large nodal counts. Due to the many parallels between biological sensory systems and engineered sensing systems, the biological nervous system can offer potential solutions to the current deficiencies of structural monitoring systems. The nervous system is capable of real-time processing and data transmission of external stimuli through an extremely condensed format with very basic processing units. This study explores the mammalian auditory system for inspiration because it achieves efficient data acquisition processes that outperform existing engineered sensing systems. Specifically, the auditory system realizes this through three steps: (1) real-time decomposition of a convoluted time-based signal into frequency components, (2) information compression for each component, and (3) efficient high-speed data transmission to the auditory cortex. In this paper, these three main mechanisms are explored and a bio-inspired structural monitoring system is proposed. The functionality of the proposed system is compared to traditional data compression techniques (wavelet transforms and compressed sensing) on various vibratory signals. While the wavelet transform is able to outperform the proposed sensor by minimizing signal reconstruction errors, the proposed bio-inspired sensor achieves similar compression rates but, unlike the others, does so using real-time processing.

  6. Comprehensive studies of the dynamics of geosystems with the use of remote sensing techniques

    NASA Astrophysics Data System (ADS)

    Vasilev, L. N.; Kaczyński, R.; Ney, B. I.

    The described research programme for comprehensive studies of changes occuring within geosystems is a part of scientific activity of INTERKOSMOS, which will be executed mainly with the use of remote sensing methods and techniques. The main aim of the programme is to get an insight into the seasonal rithm of environmental changes on both regional and global level. The work will consist of gathering systematized information concerning quantitative and qualitative relations between various components of the environment. The application of remote sensing methods enables the acquisition of such environmental data in dynamic setting. Research will be conducted for areas comprising distinct geosystems and will lead to the detection of diurnal, seasonal and yearly dynamics of geosystems as well as long-term trends. Except cognitive, the programme will also serve the methodological purpose. The first aim will be realized with respect to individual geosystems; the resulting sets of data will consist of matrixes of statistical data characterizing relations between various components of geosystems. The methodological aim will be achieved through the process of practical verification of the preliminary assumptions. Information will be collected from different data acquisition levels namely from satellite and aerial platforms and through ground measurements. Different types of data, such as multispectral photography (SALYUT, KOSMOS), multispectral scanner images (LANDSAT THEMATIC MAPPER, SPOT), infrared photography, radar imagery and spectrometric measurements will be gathered during simultaneous data acquisition projects. All types of observations will be timed in accordance with the natural rithm of the observed phenomena. The paper contains the description of geosystems under anthropogenic stress based on the previous research of the authors. The presented multifactor characteristics of soil and crops is a part of completed studies on agricultural geosystems. The results of

  7. Quantification of Virus Particles Using Nanopore-Based Resistive-Pulse Sensing Techniques

    PubMed Central

    Yang, Lu; Yamamoto, Takatoki

    2016-01-01

    Viruses have drawn much attention in recent years due to increased recognition of their important roles in virology, immunology, clinical diagnosis, and therapy. Because the biological and physical properties of viruses significantly impact their applications, quantitative detection of individual virus particles has become a critical issue. However, due to various inherent limitations of conventional enumeration techniques such as infectious titer assays, immunological assays, and electron microscopic observation, this issue remains challenging. Thanks to significant advances in nanotechnology, nanostructure-based electrical sensors have emerged as promising platforms for real-time, sensitive detection of numerous bioanalytes. In this paper, we review recent progress in nanopore-based electrical sensing, with particular emphasis on the application of this technique to the quantification of virus particles. Our aim is to provide insights into this novel nanosensor technology, and highlight its ability to enhance current understanding of a variety of viruses. PMID:27713738

  8. Comparison of some very high resolution remote sensing techniques for the monitoring of a sandy beach

    NASA Astrophysics Data System (ADS)

    Jaud, M.; Delacourt, C.; Allemand, P.; Deschamps, A.; Cancouët, R.; Ammann, J.; Grandjean, P.; Suanez, S.; Fichaut, B.; Cuq, V.

    2011-12-01

    Because the anthropogenic pressure on the coastal fringe is continuously increasing, the comprehension of morphological coastal changes is a key problem. An efficient, practical and affordable monitoring strategy is essential to investigate the physical processes that are on the origin of these changes and to model the changes to come. This paper presents an assessment of several very high resolution remote sensing techniques (DGPS, stereo-photogrammetry by drone, Terrestrial Laser Scanning and shallow-water multi-beam echo-sounder) which have been jointly used to survey a beach in French Brittany. These techniques allow an integrated approach for Digital Elevation Model (DEM) differencing in order to quantify morphological changes and to monitor the beach evolution. Gathering topographic and bathymetric data enables to draw up the sediment budget of a complete sediment compartment.

  9. Optical sensing of peroxide using ceria nanoparticles via fluorescence quenching technique

    NASA Astrophysics Data System (ADS)

    Shehata, Nader; Samir, Effat; Gaballah, Soha; Salah, Mohammed

    2016-07-01

    This study introduces the application of ceria nanoparticles (NPs) as an optical sensor for peroxide using fluorescence quenching technique. Our synthesized ceria NPs have the ability to adsorb peroxides via its oxygen vacancies. Ceria NPs solution with added variable concentrations of hydrogen peroxides is exposed through near-UV excitation and the detected visible fluorescent emission is found to be at ˜520 nm. The fluorescent intensity peak is found to be reduced with increasing the peroxide concentrations due to static fluorescence quenching technique. The relative intensity change of the visible fluorescent emission has been reduced to more than 50% at added peroxide concentrations up to 10 wt. %. In order to increase ceria peroxides sensing sensitivity, lanthanide elements such as samarium (Sm) are used as ceria NPs dopant. This research work could be applied further in optical sensors of radicals in biomedical engineering and environmental monitoring.

  10. Application of Remote Sensing Techniques for Appraising Changes in Wildlife Habitat

    NASA Technical Reports Server (NTRS)

    Nelson, H. K.; Klett, A. T.; Johnston, J. E.

    1971-01-01

    An attempt was made to investigate the potential of airborne, multispectral, line scanner data acquisition and computer-implemented automatic recognition techniques for providing useful information about waterfowl breeding habitat in North Dakota. The spectral characteristics of the components of a landscape containing waterfowl habitat can be detected with airborne scanners. By analyzing these spectral characteristics it is possible to identify and map the landscape components through analog and digital processing methods. At the present stage of development multispectral remote sensing techniques are not ready for operational application to surveys of migratory bird habitat and other such resources. Further developments are needed to: (1) increase accuracy; (2) decrease retrieval and processing time; and (3) reduce costs.

  11. Studing some water quality parametres using remote sensing techniques in the Eastern Harbor, Alexandria, Egypt

    NASA Astrophysics Data System (ADS)

    Geurguess, Maged Shoukry Kamel

    The environmental problems of Alexandria have grown rapidly in recent decades, in proportion to the growth in population and population density, as well as to the urban and industrial development. The rate of development has accelerated considerably since the turn of the century. A daily volume of more than one million cubic meters of mixed sewage water is drained from the city. About one third of this is disposed of without any treatment, into the Eastern and Western Harbors and their surroundings. The Qait Bey outfall, located a few hundred meters from the recently surveyed Pharos site, releases 200,000 m3 of waste water per day. The Eastern Harbor is the recipient of 7 outfalls. This semi-closed harbor remains permanently turbid, and water visibility is drastically reduced. Some studies were made in Eastern Harbor region, but special studies are needed to understand the variability of the water quality (Total suspended matter (TSM), transparency and chlorophyll) . Therefore, the objective of this study is to use the remote sensing application on marine environment for detecting transparency, total suspended matter and chlorophyll and its influences on Eastern Harbor based on the remote sensing techniques. Remote sensing techniques assess water quality in Eastern Harbor with special algorithms to extract all possible information using different satalittes images for the four seasons during 2006. The resulted images have been compared with ground measurements and showed high agreement significant relation between them. Eastern Harbor area are very closed and the harbor prevents the renew of water, so the transparency had been decreased while TSM and chlorophyll have been increased.

  12. Remote sensing and spatial statistical techniques for modelling Ommatissus lybicus (Hemiptera: Tropiduchidae) habitat and population densities

    PubMed Central

    Kwan, Paul; Welch, Mitchell

    2017-01-01

    In order to understand the distribution and prevalence of Ommatissus lybicus (Hemiptera: Tropiduchidae) as well as analyse their current biographical patterns and predict their future spread, comprehensive and detailed information on the environmental, climatic, and agricultural practices are essential. The spatial analytical techniques such as Remote Sensing and Spatial Statistics Tools, can help detect and model spatial links and correlations between the presence, absence and density of O. lybicus in response to climatic, environmental, and human factors. The main objective of this paper is to review remote sensing and relevant analytical techniques that can be applied in mapping and modelling the habitat and population density of O. lybicus. An exhaustive search of related literature revealed that there are very limited studies linking location-based infestation levels of pests like the O. lybicus with climatic, environmental, and human practice related variables. This review also highlights the accumulated knowledge and addresses the gaps in this area of research. Furthermore, it makes recommendations for future studies, and gives suggestions on monitoring and surveillance methods in designing both local and regional level integrated pest management strategies of palm tree and other affected cultivated crops. PMID:28875085

  13. A Study on Integrated Community Based Flood Mitigation with Remote Sensing Technique in Kota Bharu, Kelantan

    NASA Astrophysics Data System (ADS)

    'Ainullotfi, A. A.; Ibrahim, A. L.; Masron, T.

    2014-02-01

    This study is conducted to establish a community based flood management system that is integrated with remote sensing technique. To understand local knowledge, the demographic of the local society is obtained by using the survey approach. The local authorities are approached first to obtain information regarding the society in the study areas such as the population, the gender and the tabulation of settlement. The information about age, religion, ethnic, occupation, years of experience facing flood in the area, are recorded to understand more on how the local knowledge emerges. Then geographic data is obtained such as rainfall data, land use, land elevation, river discharge data. This information is used to establish a hydrological model of flood in the study area. Analysis were made from the survey approach to understand the pattern of society and how they react to floods while the analysis of geographic data is used to analyse the water extent and damage done by the flood. The final result of this research is to produce a flood mitigation method with a community based framework in the state of Kelantan. With the flood mitigation that involves the community's understanding towards flood also the techniques to forecast heavy rainfall and flood occurrence using remote sensing, it is hope that it could reduce the casualties and damage that might cause to the society and infrastructures in the study area.

  14. Groundwater resources development in hard rock terrain - an approach using remote sensing and GIS techniques

    NASA Astrophysics Data System (ADS)

    Krishnamurthy, Jagannathan; Mani, Arul; Jayaraman, Venkatakrishnan; Manivel, M.

    To demonstrate the capabilities of remote sensing and Geographic Information System (GIS) techniques for groundwater resources development in hard rock terrains, specifically for the demarcation of suitable sites for artificial recharge of groundwater aquifers, a study was carried out in the Kallar Basin, which is located in parts of the Salem and Tiruchirapalli districts, Tamil Nadu, India. Thematic maps defining lithology, lineaments, landforms, landuse, drainage density, thickness of weathered zone, thickness of fractured zone, hydrological soils, and well yield were prepared from data collected by the Indian Remote Sensing Satellite (IRS) -1C and by conventional methods. All the thematic layers were integrated using a GIS-based model developed specifically for this purpose, enabling a map showing artificial recharge zones to be generated. The exact type of artificial recharge structure, eg, check dam, nallabund, gully plugging and percolation pond, suitable for replenishing groundwater was identified by superposing a drainage network map over an artificial recharge zones map. The GIS-based demarcation of artificial zones developed in the study was based on logical conditions and reasoning, so that the same techniques (with appropriate modifications) could be adopted elsewhere, especially in hard rock terrain, where the occurrence of groundwater is restricted and subject to greater complexity.

  15. Remote sensing and spatial statistical techniques for modelling Ommatissus lybicus (Hemiptera: Tropiduchidae) habitat and population densities.

    PubMed

    Al-Kindi, Khalifa M; Kwan, Paul; R Andrew, Nigel; Welch, Mitchell

    2017-01-01

    In order to understand the distribution and prevalence of Ommatissus lybicus (Hemiptera: Tropiduchidae) as well as analyse their current biographical patterns and predict their future spread, comprehensive and detailed information on the environmental, climatic, and agricultural practices are essential. The spatial analytical techniques such as Remote Sensing and Spatial Statistics Tools, can help detect and model spatial links and correlations between the presence, absence and density of O. lybicus in response to climatic, environmental, and human factors. The main objective of this paper is to review remote sensing and relevant analytical techniques that can be applied in mapping and modelling the habitat and population density of O. lybicus. An exhaustive search of related literature revealed that there are very limited studies linking location-based infestation levels of pests like the O. lybicus with climatic, environmental, and human practice related variables. This review also highlights the accumulated knowledge and addresses the gaps in this area of research. Furthermore, it makes recommendations for future studies, and gives suggestions on monitoring and surveillance methods in designing both local and regional level integrated pest management strategies of palm tree and other affected cultivated crops.

  16. Temperature Compensation of Oxygen Sensing Films Utilizing a Dynamic Dual Lifetime Calculation Technique

    PubMed Central

    Collier, Bradley B.; McShane, Michael J.

    2014-01-01

    With advances to chemical sensing, methods for compensation of errors introduced by interfering analytes are needed. In this work, a dual lifetime calculation technique was developed to enable simultaneous monitoring of two luminescence decays. Utilizing a windowed time-domain luminescence approach, the response of two luminophores is separated temporally. The ability of the dual dynamic rapid lifetime determination (DDRLD) approach to determine the response of two luminophores simultaneously was investigated through mathematical modeling and experimental testing. Modeling results indicated that lifetime predictions will be most accurate when the ratio of the lifetimes from each luminophore is at least three and the ratio of intensities is near unity. In vitro experiments were performed using a porphyrin that is sensitive to both oxygen and temperature, combined with a temperature-sensitive inorganic phosphor used for compensation of the porphyrin response. In static experiments, the dual measurements were found to be highly accurate when compared to single-luminophore measurements—statistically equivalent for the long lifetime emission and an average difference of 2% for the short lifetimes. Real-time testing with dynamic windowing was successful in demonstrating dual lifetime measurements and temperature compensation of the oxygen sensitive dye. When comparing the actual oxygen and temperature values with predictions made using a dual calibration approach, an overall difference of less than 1% was obtained. Thus, this method enables rapid, accurate extraction of multiple lifetimes without requiring computationally intense curve fitting, providing a significant advancement toward multi-analyte sensing and imaging techniques. PMID:26566384

  17. Differential Radiometers Using Fabry-Perot Interferometric Technique for Remote Sensing of Greenhouse Gases

    NASA Technical Reports Server (NTRS)

    Georgieva, Elena M.; Heaps,William S.; Wilson, Emily L.

    2007-01-01

    A new type of remote sensing radiometer based upon the Fabry-Perot interferometric technique has been developed at NASA's Goddard Space Flight Center and tested from both ground and aircraft platform. The sensor uses direct or reflected sunlight and has channels for measuring column concentration of carbon dioxide at 1570 nm, oxygen lines sensitive to pressure and temperature at 762 and 768 nm, and water vapor (940 nm). A solid Fabry-Perot etalon is used as a tunable narrow bandpass filter to restrict the measurement to the gas of interest's absorption bands. By adjusting the temperature of the etalon, which changes the index of refraction of its material, the transmission fringes can be brought into nearly exact correspondence with absorption lines of the particular species. With this alignment between absorption lines and fringes, changes in the amount of a species in the atmosphere strongly affect the amount of light transmitted by the etalon and can be related to gas concentration. The technique is applicable to different chemical species. We have performed simulations and instrument design studies for CH4, "Cot isotope, and CO detection. Index Terms- Absorbing media, Atmospheric measurements, Fabry-Perot interferometers, Optical interferometry, Remote sensing.

  18. On the Estimation of Forest Resources Using 3D Remote Sensing Techniques and Point Cloud Data

    NASA Astrophysics Data System (ADS)

    Karjalainen, Mika; Karila, Kirsi; Liang, Xinlian; Yu, Xiaowei; Huang, Guoman; Lu, Lijun

    2016-08-01

    In recent years, 3D capable remote sensing techniques have shown great potential in forest biomass estimation because of their ability to measure the forest canopy structure, tree height and density. The objective of the Dragon3 forest resources research project (ID 10667) and the supporting ESA young scientist project (ESA contract NO. 4000109483/13/I-BG) was to study the use of satellite based 3D techniques in forest tree height estimation, and consequently in forest biomass and biomass change estimation, by combining satellite data with terrestrial measurements. Results from airborne 3D techniques were also used in the project. Even though, forest tree height can be estimated from 3D satellite SAR data to some extent, there is need for field reference plots. For this reason, we have also been developing automated field plot measurement techniques based on Terrestrial Laser Scanning data, which can be used to train and calibrate satellite based estimation models. In this paper, results of canopy height models created from TerraSAR-X stereo and TanDEM-X INSAR data are shown as well as preliminary results from TLS field plot measurement system. Also, results from the airborne CASMSAR system to measure forest canopy height from P- and X- band INSAR are presented.

  19. Comparison of remote sensing image processing techniques to identify tornado damage areas from Landsat TM data

    USGS Publications Warehouse

    Myint, S.W.; Yuan, M.; Cerveny, R.S.; Giri, C.P.

    2008-01-01

    Remote sensing techniques have been shown effective for large-scale damage surveys after a hazardous event in both near real-time or post-event analyses. The paper aims to compare accuracy of common imaging processing techniques to detect tornado damage tracks from Landsat TM data. We employed the direct change detection approach using two sets of images acquired before and after the tornado event to produce a principal component composite images and a set of image difference bands. Techniques in the comparison include supervised classification, unsupervised classification, and objectoriented classification approach with a nearest neighbor classifier. Accuracy assessment is based on Kappa coefficient calculated from error matrices which cross tabulate correctly identified cells on the TM image and commission and omission errors in the result. Overall, the Object-oriented Approach exhibits the highest degree of accuracy in tornado damage detection. PCA and Image Differencing methods show comparable outcomes. While selected PCs can improve detection accuracy 5 to 10%, the Object-oriented Approach performs significantly better with 15-20% higher accuracy than the other two techniques. ?? 2008 by MDPI.

  20. Comparison of Remote Sensing Image Processing Techniques to Identify Tornado Damage Areas from Landsat TM Data

    PubMed Central

    Myint, Soe W.; Yuan, May; Cerveny, Randall S.; Giri, Chandra P.

    2008-01-01

    Remote sensing techniques have been shown effective for large-scale damage surveys after a hazardous event in both near real-time or post-event analyses. The paper aims to compare accuracy of common imaging processing techniques to detect tornado damage tracks from Landsat TM data. We employed the direct change detection approach using two sets of images acquired before and after the tornado event to produce a principal component composite images and a set of image difference bands. Techniques in the comparison include supervised classification, unsupervised classification, and object-oriented classification approach with a nearest neighbor classifier. Accuracy assessment is based on Kappa coefficient calculated from error matrices which cross tabulate correctly identified cells on the TM image and commission and omission errors in the result. Overall, the Object-oriented Approach exhibits the highest degree of accuracy in tornado damage detection. PCA and Image Differencing methods show comparable outcomes. While selected PCs can improve detection accuracy 5 to 10%, the Object-oriented Approach performs significantly better with 15-20% higher accuracy than the other two techniques. PMID:27879757

  1. Lighter-Than-Air Blimps As a Testbed For River Remote Sensing Techniques

    NASA Astrophysics Data System (ADS)

    Fonstad, M. A.

    2010-12-01

    River science has seen a methodological revolution during the past decade as new platforms, sensors, and processing algorithms have allowed the remote collection of river data with ever-increasing ease, accuracy, precision, and extent. Recently, hand-held, low cost lighter-than-air blimps have been suggested as an important platform for river remote sensing, particularly when high-resolution and low-cost imaging is required. Because blimps are small, inexpensive, and relatively simple to operate in the field, they allow rapid river remote sensing trials, particularly over shorter river reaches. Unlike most airborne or satellite approaches, hand-held blimps can also be used to do very rapid repeat imaging. Field experiments show that such hand-held platforms are not as stable as most airborne and satellite platforms, and they have far reduced lift, allowing only very small and simple camera systems. They are also susceptible to become entangled in near-channel trees, and almost always have the problem of inclusion of the operator somewhere in resulting image. These issues notwithstanding, the simple adjustment of blimp tether length can easily allow adjustment of ground resolution to extremely high levels, and programmable cameras can allow versatility in automatic camera shutter intervals, shutter speeds, and other image constraints. We utilize low-altitude helikite platforms to test the potential for remote sensing (a) well geometrically-controlled measurements of water surface configuration, (b) submerged and near-channel sediment sizes, (c) water depth, and (d) surface velocity. The velocity imaging techniques include the use of natural and artificial particle image velocimetry (PIV) features, with velocity extracted using either the principles of motion blur or from sequential images. In addition, we use these low-cost, mobile platforms to test the brightness and color effects of shadows cast upon the water surface, and use these results to suggest potential

  2. Quantifying Stream Habitat: Relative Effort Versus Quality of Competing Remote Sensing & Ground-Based Survey Techniques

    NASA Astrophysics Data System (ADS)

    Bangen, S. G.; Wheaton, J. M.; Bouwes, N.

    2010-12-01

    Numerous field and analytical methods exist to assist in the quantification of the quantity and quality of in-stream habitat for salmonids. These methods range from field sketches or ‘tape and stick’ ground-based surveys, through to spatially explicit topographic and aerial photographic surveys from a mix of ground-based and remotely sensed airborne platforms. Although some investigators have assessed the quality of specific individual survey methods, the inter-comparison of competing techniques across a diverse range of habitat conditions (wadeable headwater channels to non-wadeable mainstem channels) has not yet been elucidated. In this study, we seek to quantify relative quality (i.e. accuracy, precision, extent) of habitat metrics and inventories derived from different ground-based and remotely sensed surveys of varying degrees of sophistication, as well as enumerate the effort and cost in completing the surveys. Over the summer of 2010, seven sample reaches of varying habitat complexity were surveyed in the Lemhi River Basin, Idaho, USA. Three different traditional (“stick and tape”) survey techniques were used, including a variant using map-grade GPS. Complete topographic/bathymetric surveys were attempted at each site using separate rtkGPS, total station, ground-based LiDaR, boat-based echo-sounding (w/ ADCP), traditional airborne LiDaR, and imagery-based spectral methods. Separate, georectified aerial imagery surveys were acquired using a tethered blimp, a drone UAV, and a traditional fixed-wing aircraft. Preliminary results from the surveys highlight that no single technique works across the full range of conditions where stream habitat surveys are needed. The results are helpful for understanding the strengths and weaknesses of each approach in specific conditions, and how a hybrid of data acquisition methods can be used to build a more complete quantification of habitat conditions in rivers.

  3. Laboratory insights into the detection of surface biosignatures by remote-sensing techniques

    NASA Astrophysics Data System (ADS)

    Poch, O.; Pommerol, A.; Jost, B.; Roditi, I.; Frey, J.; Thomas, N.

    2014-03-01

    With the progress of direct imaging techniques, it will be possible in the short or long-term future to retrieve more efficiently the information on the physical properties of the light reflected by rocky exoplanets (Traub et al., 2010). The search for visible-infrared absorption bands of peculiar gases (O2, CH4 etc.) in this light could give clues for the presence of life (Kaltenegger and Selsis, 2007). Even more uplifting would be the direct detection of life itself, on the surface of an exoplanet. Considering this latter possibility, what is the potential of optical remote-sensing methods to detect surface biosignatures? Reflected light from the surface of the Earth exhibits a strong surface biosignature in the form of an abrupt change of reflectance between the visible and infrared range of the spectrum (Seager et al., 2005). This spectral feature called "vegetation red-edge" is possibly the consequence of biological evolution selecting the right chemical structures enabling the plants to absorb the visible energy, while preventing them from overheating by reflecting more efficiently the infrared. Such red-edge is also found in primitive photosynthetic bacteria, cyanobacteria, that colonized the surface of the Earth ocean and continents billions of years before multicellular plants (Knacke, 2003). If life ever arose on an Earth-like exoplanet, one could hypothesize that some form of its surface-life evolves into similar photo-active organisms, also exhibiting a red-edge. In this paper, we will present our plan and preliminary results of a laboratory study aiming at precising the potentiality of remote sensing techniques in detecting such surface biosignatures. Using equipment that has been developed in our team for surface photometry studies (Pommerol 2011, Jost 2013, Pommerol 2013), we will investigate the reflectance spectra and bidirectional reflectance function of soils containing bacteria such as cyanobacteria, in various environmental conditions. We will

  4. Mapping land slide occurrence zones using Remote Sensing and GIS techniques in Kelantan state, Malaysia

    NASA Astrophysics Data System (ADS)

    Hashim, M.; Pour, A. B.; Misbari, S.

    2017-05-01

    Integration of satellite remote sensing data and Geographic Information System (GIS) techniques is one of the most applicable approach for landslide mapping and identification of high potential risk and susceptible zones in tropical environments. Yearly, several landslides occur during heavy monsoon rainfall in Kelantan river basin, Peninsular Malaysia. In this investigation, Landsat-8 and Phased Array type L-band Synthetic Aperture Radar-2 (PALSAR-2) remote sensing data sets were integrated with GIS analysis for detect, map and characterize landslide occurrences during December 2014 flooding period in the Kelantan river basin. Landslides were determined by tracking changes in vegetation pixel data using Landsat-8 images that acquired before and after December 2014 flooding for the study area. The PALSAR-2 data were used for mapping of major geological structures and detailed characterizations of lineaments in the state of Kelantan. Analytical Hierarchy Process (AHP) approach was used for landslide susceptibility mapping. Several factors such as slope, aspect, soil, lithology, Normalized Difference Vegetation Index (NDVI), land cover, distance to drainage, precipitation, distance to fault, and distance to road were extracted from remote sensing satellite data and fieldwork to apply AHP approach. Two main outputs of this study were landslide inventory occurrences map during 2014 flooding episode and landslide susceptibility map for entire the Kelantan state. Modelled/predicted landslides with susceptible map generated prior and post flood episode, confirmed that intense rainfall in the Kelantan have contributed to weightage of numerous landslides with various sizes. It is concluded that precipitation is the most influential factor that bare to landslide event.

  5. Quantifying the change in soil moisture modeling uncertainty from remote sensing observations using Bayesian inference techniques

    NASA Astrophysics Data System (ADS)

    Harrison, Kenneth W.; Kumar, Sujay V.; Peters-Lidard, Christa D.; Santanello, Joseph A.

    2012-11-01

    Operational land surface models (LSMs) compute hydrologic states such as soil moisture that are needed for a range of important applications (e.g., drought, flood, and weather prediction). The uncertainty in LSM parameters is sufficiently great that several researchers have proposed conducting parameter estimation using globally available remote sensing data to identify best fit local parameter sets. However, even with in situ data at fine modeling scales, there can be significant remaining uncertainty in LSM parameters and outputs. Here, using a new uncertainty estimation subsystem of the NASA Land Information System (LIS) (described herein), a Markov chain Monte Carlo (MCMC) technique is applied to conduct Bayesian analysis for the accounting of parameter uncertainties. The Differential Evolution Markov Chain (DE-MC) MCMC algorithm was applied, for which a new parallel implementation was developed. A case study is examined that builds on previous work in which the Noah LSM was calibrated to passive (L-band) microwave remote sensing estimates of soil moisture for the Walnut Gulch Experimental Watershed. In keeping with prior related studies, the parameters subjected to the analysis were restricted to the soil hydraulic properties (SHPs). The main goal is to estimate SHPs and soil moisture simulation uncertainty before and after consideration of the remote sensing data. The prior SHP uncertainty is based on the original source of the standard SHP lookup tables for the Noah LSM. Conclusions are drawn regarding the value and viability of Bayesian analysis over alternative approaches (e.g., parameter estimation, lookup tables) and further research needs are identified.

  6. Remote sensing and GIS techniques for assessing decadal glacier changes in the Sikkim and Nepal Himalayas

    NASA Astrophysics Data System (ADS)

    Racoviteanu, A.

    2009-04-01

    There is urgency in developing and testing remote sensing tools for developing extensive glacier datasets in high altitude areas of the Himalayas. Detailed information about glacier parameters is missing in many areas of the Himalayas, limiting our understanding of glacier fluctuations in this area. One of the biggest challenges in glacier mapping from spaceborne imagery is the delineation of debris-covered glacial tongues. The high Himalayas provide interesting challenges and unique opportunities for testing glacier mapping algorithms including debris cover. This research exploits the potential of visible, infrared and thermal ASTER data combined with SRTM elevation datasets for mapping glacier parameters (glacier area, elevations and snow lines) in the Himalayas. Multi-spectral classification techniques (ASTER ¾ band ratios and normalized differences NDSI and NDVI), single band thresholds, topographic characteristics (elevation and slope) and thermal information were combined in a decision tree to map clean ice and debris-covered ice. Snow lines were mapped from ASTER imagery acquired at the end of the ablation season, with instrument gains suitable for snow and ice. Ground control points (GCPs) collected in the field were used to assess the accuracy of the remote sensing-derived elevations. Changes in glacier parameters were derived by comparison with glacier datasets from older topographic maps and were linked with changes in climate parameters (precipitation and temperature).

  7. A Comprehensive Review on Water Quality Parameters Estimation Using Remote Sensing Techniques

    PubMed Central

    Gholizadeh, Mohammad Haji; Melesse, Assefa M.; Reddi, Lakshmi

    2016-01-01

    Remotely sensed data can reinforce the abilities of water resources researchers and decision makers to monitor waterbodies more effectively. Remote sensing techniques have been widely used to measure the qualitative parameters of waterbodies (i.e., suspended sediments, colored dissolved organic matter (CDOM), chlorophyll-a, and pollutants). A large number of different sensors on board various satellites and other platforms, such as airplanes, are currently used to measure the amount of radiation at different wavelengths reflected from the water’s surface. In this review paper, various properties (spectral, spatial and temporal, etc.) of the more commonly employed spaceborne and airborne sensors are tabulated to be used as a sensor selection guide. Furthermore, this paper investigates the commonly used approaches and sensors employed in evaluating and quantifying the eleven water quality parameters. The parameters include: chlorophyll-a (chl-a), colored dissolved organic matters (CDOM), Secchi disk depth (SDD), turbidity, total suspended sediments (TSS), water temperature (WT), total phosphorus (TP), sea surface salinity (SSS), dissolved oxygen (DO), biochemical oxygen demand (BOD) and chemical oxygen demand (COD). PMID:27537896

  8. Realization of daily evapotranspiration in arid ecosystems based on remote sensing techniques

    NASA Astrophysics Data System (ADS)

    Elhag, Mohamed; Bahrawi, Jarbou A.

    2017-03-01

    Daily evapotranspiration is a major component of water resources management plans. In arid ecosystems, the quest for an efficient water budget is always hard to achieve due to insufficient irrigational water and high evapotranspiration rates. Therefore, monitoring of daily evapotranspiration is a key practice for sustainable water resources management, especially in arid environments. Remote sensing techniques offered a great help to estimate the daily evapotranspiration on a regional scale. Existing open-source algorithms proved to estimate daily evapotranspiration comprehensively in arid environments. The only deficiency of these algorithms is the course scale of the used remote sensing data. Consequently, the adequate downscaling algorithm is a compulsory step to rationalize an effective water resources management plan. Daily evapotranspiration was estimated fairly well using an Advance Along-Track Scanner Radiometer (AATSR) in conjunction with (MEdium Resolution Imaging Spectrometer) MERIS data acquired in July 2013 with 1 km spatial resolution and 3 days of temporal resolution under a surface energy balance system (SEBS) model. Results were validated against reference evapotranspiration ground truth values using standardized Penman-Monteith method with R2 of 0.879. The findings of the current research successfully monitor turbulent heat fluxes values estimated from AATSR and MERIS data with a temporal resolution of 3 days only in conjunction with reliable meteorological data. Research verdicts are necessary inputs for a well-informed decision-making processes regarding sustainable water resource management.

  9. Use of remote-sensing techniques to survey the physical habitat of large rivers

    USGS Publications Warehouse

    Edsall, Thomas A.; Behrendt, Thomas E.; Cholwek, Gary; Frey, Jeffery W.; Kennedy, Gregory W.; Smith, Stephen B.; Edsall, Thomas A.; Behrendt, Thomas E.; Cholwek, Gary; Frey, Jeffrey W.; Kennedy, Gregory W.; Smith, Stephen B.

    1997-01-01

    Remote-sensing techniques that can be used to quantitatively characterize the physical habitat in large rivers in the United States where traditional survey approaches typically used in small- and medium-sized streams and rivers would be ineffective or impossible to apply. The state-of-the-art remote-sensing technologies that we discuss here include side-scan sonar, RoxAnn, acoustic Doppler current profiler, remotely operated vehicles and camera systems, global positioning systems, and laser level survey systems. The use of these technologies will permit the collection of information needed to create computer visualizations and hard copy maps and generate quantitative databases that can be used in real-time mode in the field to characterize the physical habitat at a study location of interest and to guide the distribution of sampling effort needed to address other habitat-related study objectives. This report augments habitat sampling and characterization guidance provided by Meador et al. (1993) and is intended for use primarily by U.S. Geological Survey National Water Quality Assessment program managers and scientists who are documenting water quality in streams and rivers of the United States.

  10. A Comprehensive Review on Water Quality Parameters Estimation Using Remote Sensing Techniques.

    PubMed

    Gholizadeh, Mohammad Haji; Melesse, Assefa M; Reddi, Lakshmi

    2016-08-16

    Remotely sensed data can reinforce the abilities of water resources researchers and decision makers to monitor waterbodies more effectively. Remote sensing techniques have been widely used to measure the qualitative parameters of waterbodies (i.e., suspended sediments, colored dissolved organic matter (CDOM), chlorophyll-a, and pollutants). A large number of different sensors on board various satellites and other platforms, such as airplanes, are currently used to measure the amount of radiation at different wavelengths reflected from the water's surface. In this review paper, various properties (spectral, spatial and temporal, etc.) of the more commonly employed spaceborne and airborne sensors are tabulated to be used as a sensor selection guide. Furthermore, this paper investigates the commonly used approaches and sensors employed in evaluating and quantifying the eleven water quality parameters. The parameters include: chlorophyll-a (chl-a), colored dissolved organic matters (CDOM), Secchi disk depth (SDD), turbidity, total suspended sediments (TSS), water temperature (WT), total phosphorus (TP), sea surface salinity (SSS), dissolved oxygen (DO), biochemical oxygen demand (BOD) and chemical oxygen demand (COD).

  11. Exploring social sensing techniques for measuring rainfall and flood response in urban environments

    NASA Astrophysics Data System (ADS)

    Koole, Wouter; Sips, Robert-Jan; ten Veldhuis, Marie-claire

    2016-04-01

    Extreme rainfall is expected to occur more often in the future as a result of climate change. To be able to react to this, urban water managers need to accurately know vulnerable spots in the city, as well as the potential impact to society. Currently, detailed information about rainfall intensities in cities, and effects of intense storm events on urban societies is lacking. In this study, we will present first results of social sensing experiments to measure rainfall and flooding using a smartphone app. Users of the app are asked to submit rainfall reports by selecting an rainfall class from a pre-defined list of (6) classes, to register time and location and to make a photo of the rainfall. Rainfall photos will be used in a future experiment for automated retrieval of rainfall classes using computer vision techniques. With the experiments we aim to validate rainfall observations made by lay people and to evaluate factors that influence the willingness of users to contribute observations. The results show that users consistently distinguish heavy and extreme rainfall from drizzle and mild rainfall, but have difficulty in making more detailed distinctions. The main factor driving willingness to contribute to the social rainfall sensing experiments is the perceived usefulness of rainfall reporting.

  12. Nondestructive, in-process inspection of inertia friction welding : an investigation into a new sensing technique.

    SciTech Connect

    Hartman, D. A.; Cola, M. J.; Dave, V. R.; Dozhier, N. G.; Carpenter, R. W.

    2002-01-01

    This paper investigates the capabilities of a new sensor for in-process monitoring of quality during friction welding. The non-contact sensor is composed of microphones that are mounted in an aluminum ring which surrounds the weld joint. The sensor collects the acoustical energy (in the form of sound pressure) that is emitted during the plastic deformation and phase transformations (if applicable) in friction welding processes. The focus in this preliminary investigation is to search for and identify features within the acoustical emission that are indicative of bond quality. Bar-to-bar inertia friction welding (one form of friction welding) of copper to 304L stainless steel is used in this proof-of-concept study. This material combination exhibits only marginal weldability and is ideally suited for validating the capabilities of this new sensing technique. A probabilistic neural network is employed in this work to analyze the acoustical emission's frequency spectrum in an attempt to classify acceptable, conditional, and unacceptable welds. Our preliminary findings indicate that quality-based process features do exist within the frequency spectrum of the acoustical signature. The results from this analysis are presented. Future work in improving the sensing and interpretation of the data is discussed in an effort to develop a robust method of quality-based, in-process monitoring of friction welds.

  13. Nanoscale electrode arrays produced with microscale lithographic techniques for use in biomedical sensing applications.

    PubMed

    Terry, Jonathan G; Schmüser, Ilka; Underwood, Ian; Corrigan, Damion K; Freeman, Neville J; Bunting, Andrew S; Mount, Andrew R; Walton, Anthony J

    2013-12-01

    A novel technique for the production of nanoscale electrode arrays that uses standard microfabrication processes and micron-scale photolithography is reported here in detail. These microsquare nanoband edge electrode (MNEE) arrays have been fabricated with highly reproducible control of the key array dimensions, including the size and pitch of the individual elements and, most importantly, the width of the nanoband electrodes. The definition of lateral features to nanoscale dimensions typically requires expensive patterning techniques that are complex and low-throughput. However, the fabrication methodology used here relies on the fact that vertical dimensions (i.e. layer thicknesses) have long been manufacturable at the nanoscale using thin film deposition techniques that are well established in mainstream microelectronics. The authors report for the first time two aspects that highlight the particular suitability of these MNEE array systems for probe monolayer biosensing. The first is simulation, which shows the enhanced sensitivity to the redox reaction of the solution redox couple. The second is the enhancement of probe film functionalisation observed for the probe film model molecule, 6-mercapto-1-hexanol compared with microsquare electrodes. Such surface modification for specific probe layer biosensing and detection is of significance for a wide range of biomedical and other sensing and analytical applications.

  14. Noninvasive glucose sensing in scattering media using OCT, PAS, and TOF techniques

    NASA Astrophysics Data System (ADS)

    Alarousu, Erkki; Hast, Jukka T.; Kinnunen, Matti T.; Kirillin, Mikhail Y.; Myllyla, Risto A.; Plucinski, Jerzy; Popov, Alexey P.; Priezzhev, Alexander V.; Prykari, Tuukka; Saarela, Juha; Zhao, Zuomin

    2004-08-01

    In this paper, optical measurement techniques, which enable non-invasive measurement, are superimposed to glucose sensing in scattering media. Used measurement techniques are Optical Coherence Tomography (OCT), Photoacoustic spectroscopy (PAS) and laser pulse Time-of-Flight (TOF) measurement using a streak camera. In parallel with measurements, a Monte-Carlo (MC) simulation models have been developed. Experimental in vitro measurements were performed using Intralipid fat emulsion as a tissue simulating phantom for OCT and TOF measurements. In PAS measurements, a pork meat was used as a subject but also preliminary in vivo measurements were done. OCT measurement results show that the slope of the OCT signal's envelope changes as a function of glucose content in the scattering media. TOF measurements show that the laser pulse full width of half maximum (FWHM) changes a little as function of glucose content. An agreement with MC-simulations and measurements with Intralipid was also found. Measurement results of PAS technique show that changes in glucose content in the pork meat tissue can be measured. In vivo measurements with a human volunteer show that other factors such as physiological change, blood circulation and body temperature drift may interfere the PA response of glucose.

  15. Full-scale monitoring system for structural prestress loss based on distributed brillouin sensing technique

    NASA Astrophysics Data System (ADS)

    Chunguang, Lan; Liguang, Zhou; Zhiyu, Huo

    2017-08-01

    Prestress loss is critical to impact the safety of prestressed structures. Unfortunately, up to date, there are no qualified techniques to handle this issue due to the fact that it is too hard for sensors to survive the harsh construction environments and the time-dependent service life of the large-span prestressed structures. This paper proposes a novel technique to monitor prestress loss in prestressed beams using Brillouin optical fiber sensors. A novel smart steel strand based on the sensing technique of full-scale Brillouin optical fiber sensors was introduced. Two kinds of prestressed structure were used to verify the concept of monitoring prestress loss using smart steel strands. The prestress loss data have been taken by Brillouin optical fiber sensors. And the monitoring results agree well with those from the conventional sensors. The monitoring data can reveal both the full-scale distribution and the time history of prestress loss during the construction stage and also in-service phrase.

  16. Remote sensing of row crop structure and component temperatures using directional radiometric temperatures and inversion techniques

    NASA Technical Reports Server (NTRS)

    Kimes, D. S.

    1983-01-01

    A physically based sensor response model of a row crop was used as the mathematical framework from which several inversion strategies were tested for extracting row structure information and component temperatures using a series of sensor view angles. The technique was evaluated on ground-based radiometric thermal infrared data of a cotton row crop that covered 48 percent of the ground in the vertical projection. The results showed that the accuracies of the predicted row heights and widths, vegetation temperatures, and soil temperatures of the cotton row crop were on the order of 5 cm, 1 deg, and 2 deg C, respectively. The inversion techniques can be applied to directional sensor data from aircraft platforms and even space platforms if the effects of atmospheric absorption and emission can be corrected. In theory, such inversion techniques can be applied to a wide variety of vegetation types and thus can have significant implications for remote sensing research and applications in disciplines that deal with incomplete vegetation canopies.

  17. Remote sensing of temperature profiles in vegetation canopies using multiple view angles and inversion techniques

    NASA Technical Reports Server (NTRS)

    Kimes, D. S.

    1981-01-01

    A mathematical method is presented which allows the determination of vertical temperature profiles of vegetation canopies from multiple sensor view angles and some knowledge of the vegetation geometric structure. The technique was evaluated with data from several wheat canopies at different stages of development, and shown to be most useful in the separation of vegetation and substrate temperatures with greater accuracy in the case of intermediate and dense vegetation canopies than in sparse ones. The converse is true for substrate temperatures. Root-mean-square prediction accuracies of temperatures for intermediate-density wheat canopies were 1.8 C and 1.4 C for an exact and an overdeterminate system, respectively. The findings have implication for remote sensing research in agriculture, geology or other earth resources disciplines.

  18. Comparison of multispectral remote-sensing techniques for monitoring subsurface drain conditions. [Imperial Valley, California

    NASA Technical Reports Server (NTRS)

    Goettelman, R. C.; Grass, L. B.; Millard, J. P.; Nixon, P. R.

    1983-01-01

    The following multispectral remote-sensing techniques were compared to determine the most suitable method for routinely monitoring agricultural subsurface drain conditions: airborne scanning, covering the visible through thermal-infrared (IR) portions of the spectrum; color-IR photography; and natural-color photography. Color-IR photography was determined to be the best approach, from the standpoint of both cost and information content. Aerial monitoring of drain conditions for early warning of tile malfunction appears practical. With careful selection of season and rain-induced soil-moisture conditions, extensive regional surveys are possible. Certain locations, such as the Imperial Valley, Calif., are precluded from regional monitoring because of year-round crop rotations and soil stratification conditions. Here, farms with similar crops could time local coverage for bare-field and saturated-soil conditions.

  19. Formulation of a General Technique for Predicting Pneumatic Attenuation Errors in Airborne Pressure Sensing Devices

    NASA Technical Reports Server (NTRS)

    Whitmore, Stephen A.

    1988-01-01

    Presented is a mathematical model derived from the Navier-Stokes equations of momentum and continuity, which may be accurately used to predict the behavior of conventionally mounted pneumatic sensing systems subject to arbitrary pressure inputs. Numerical techniques for solving the general model are developed. Both step and frequency response lab tests were performed. These data are compared with solutions of the mathematical model and show excellent agreement. The procedures used to obtain the lab data are described. In-flight step and frequency response data were obtained. Comparisons with numerical solutions of the math model show good agreement. Procedures used to obtain the flight data are described. Difficulties encountered with obtaining the flight data are discussed.

  20. Feasibility of estimating rice planting area of hilly region in southern China using remote sensing technique

    NASA Astrophysics Data System (ADS)

    Lai, Geying; Yang, Xingwei

    1998-08-01

    The objective of the study (Zhejiang province as study area) was to estimate rice planting area of hilly region in southern part of China by remote sensing technique with NOAA/AVHRR data. The research contents mainly concerned contrast tests on practical approaches, both digital elevation model (DEM) and digital slope model (DSM) derived from the digital relief map were used for the purpose of improving the classification accuracy of AVHRR imagery in large-area hilly region. The results indicated that the accuracy of maximum-likelihood (MLH) classification could satisfy the professional requirements of estimating rice planting area and fuzzy supervised classification based on unmixing AVHRR imagery has better classification accuracy and stability than MLH. In addition, the results through using both DEM and DSM as ancillary categorization data suggests DSM may improve the results of extracting paddy field signatures from AVHRR, particularly may improve the spatial accuracy, while DEM contribute nothing to improve the accuracy mentioned above.

  1. Formulaton of a general technique for predicting pneumatic attenuation errors in airborne pressure sensing devices

    NASA Technical Reports Server (NTRS)

    Whitmore, Stephen A.

    1988-01-01

    Presented is a mathematical model, derived from the Navier-Stokes equations of momentum and continuity, which may be accurately used to predict the behavior of conventionally mounted pneumatic sensing systems subject to arbitrary pressure inputs. Numerical techniques for solving the general model are developed. Both step and frequency response lab tests were performed. These data are compared against solutions of the mathematical model. The comparisons show excellent agreement. The procedures used to obtain the lab data are described. In-flight step and frequency response data were obtained. Comparisons with numerical solutions of the mathematical model show good agreement. Procedures used to obtain the flight data are described. Difficulties encountered with obtaining the flight data are discussed.

  2. Application of remote sensing techniques to the geology of the bonanza volcanic center

    NASA Technical Reports Server (NTRS)

    Marrs, R. W.

    1973-01-01

    A program is reported for evaluating remote sensing as an aid to geologic mapping for the past four years. Data tested in this evaluation include color and color infrared photography, multiband photography, low sun-angle photography, thermal infrared scanner imagery, and side-looking airborne radar. The relative utility of color and color infrared photography was tested as it was used to refine geologic maps in previously mapped areas, as field photos while mapping in the field, and in making photogeologic maps prior to field mapping. The latter technique served as a test of the maximum utility of the photography. In this application the photography was used successfully to locate 75% of all faults in a portion of the geologically complex Bonanza volcanic center and to map and correctly identify 93% of all Quaternary deposits and 62% of all areas of Tertiary volcanic outcrop in the area.

  3. Remote sensing of temperature profiles in vegetation canopies using multiple view angles and inversion techniques

    NASA Technical Reports Server (NTRS)

    Kimes, D. S.

    1981-01-01

    A mathematical method is presented which allows the determination of vertical temperature profiles of vegetation canopies from multiple sensor view angles and some knowledge of the vegetation geometric structure. The technique was evaluated with data from several wheat canopies at different stages of development, and shown to be most useful in the separation of vegetation and substrate temperatures with greater accuracy in the case of intermediate and dense vegetation canopies than in sparse ones. The converse is true for substrate temperatures. Root-mean-square prediction accuracies of temperatures for intermediate-density wheat canopies were 1.8 C and 1.4 C for an exact and an overdeterminate system, respectively. The findings have implication for remote sensing research in agriculture, geology or other earth resources disciplines.

  4. A Study of Flood Evacuation Center Using GIS and Remote Sensing Technique

    NASA Astrophysics Data System (ADS)

    Mustaffa, A. A.; Rosli, M. F.; Abustan, M. S.; Adib, R.; Rosli, M. I.; Masiri, K.; Saifullizan, B.

    2016-07-01

    This research demonstrated the use of Remote Sensing technique and GIS to determine the suitability of an evacuation center. This study was conducted in Batu Pahat areas that always hit by a series of flood. The data of Digital Elevation Model (DEM) was obtained by ASTER database that has been used to delineate extract contour line and elevation. Landsat 8 image was used for classification purposes such as land use map. Remote Sensing incorporate with GIS techniques was used to determined the suitability location of the evacuation center from contour map of flood affected areas in Batu Pahat. GIS will calculate the elevation of the area and information about the country of the area, the road access and percentage of the affected area. The flood affected area map may provide the suitability of the flood evacuation center during the several levels of flood. The suitability of evacuation centers can be determined based on several criteria and the existing data of the evacuation center will be analysed. From the analysis among 16 evacuation center listed, there are only 8 evacuation center suitable for the usage during emergency situation. The suitability analysis was based on the location and the road access of the evacuation center toward the flood affected area. There are 10 new locations with suitable criteria of evacuation center proposed on the study area to facilitate the process of rescue and evacuating flood victims to much safer and suitable locations. The results of this study will help in decision making processes and indirectly will help organization such as fire-fighter and the Department of Social Welfare in their work. Thus, this study can contribute more towards the society.

  5. Mapping aboveground woody biomass using forest inventory, remote sensing and geostatistical techniques.

    PubMed

    Yadav, Bechu K V; Nandy, S

    2015-05-01

    Mapping forest biomass is fundamental for estimating CO₂ emissions, and planning and monitoring of forests and ecosystem productivity. The present study attempted to map aboveground woody biomass (AGWB) integrating forest inventory, remote sensing and geostatistical techniques, viz., direct radiometric relationships (DRR), k-nearest neighbours (k-NN) and cokriging (CoK) and to evaluate their accuracy. A part of the Timli Forest Range of Kalsi Soil and Water Conservation Division, Uttarakhand, India was selected for the present study. Stratified random sampling was used to collect biophysical data from 36 sample plots of 0.1 ha (31.62 m × 31.62 m) size. Species-specific volumetric equations were used for calculating volume and multiplied by specific gravity to get biomass. Three forest-type density classes, viz. 10-40, 40-70 and >70% of Shorea robusta forest and four non-forest classes were delineated using on-screen visual interpretation of IRS P6 LISS-III data of December 2012. The volume in different strata of forest-type density ranged from 189.84 to 484.36 m(3) ha(-1). The total growing stock of the forest was found to be 2,024,652.88 m(3). The AGWB ranged from 143 to 421 Mgha(-1). Spectral bands and vegetation indices were used as independent variables and biomass as dependent variable for DRR, k-NN and CoK. After validation and comparison, k-NN method of Mahalanobis distance (root mean square error (RMSE) = 42.25 Mgha(-1)) was found to be the best method followed by fuzzy distance and Euclidean distance with RMSE of 44.23 and 45.13 Mgha(-1) respectively. DRR was found to be the least accurate method with RMSE of 67.17 Mgha(-1). The study highlighted the potential of integrating of forest inventory, remote sensing and geostatistical techniques for forest biomass mapping.

  6. Advancements in sensing and perception using structured lighting techniques :an LDRD final report.

    SciTech Connect

    Novick, David Keith; Padilla, Denise D.; Davidson, Patrick A. Jr.; Carlson, Jeffrey J.

    2005-09-01

    This report summarizes the analytical and experimental efforts for the Laboratory Directed Research and Development (LDRD) project entitled ''Advancements in Sensing and Perception using Structured Lighting Techniques''. There is an ever-increasing need for robust, autonomous ground vehicles for counterterrorism and defense missions. Although there has been nearly 30 years of government-sponsored research, it is undisputed that significant advancements in sensing and perception are necessary. We developed an innovative, advanced sensing technology for national security missions serving the Department of Energy, the Department of Defense, and other government agencies. The principal goal of this project was to develop an eye-safe, robust, low-cost, lightweight, 3D structured lighting sensor for use in broad daylight outdoor applications. The market for this technology is wide open due to the unavailability of such a sensor. Currently available laser scanners are slow, bulky and heavy, expensive, fragile, short-range, sensitive to vibration (highly problematic for moving platforms), and unreliable for outdoor use in bright sunlight conditions. Eye-safety issues are a primary concern for currently available laser-based sensors. Passive, stereo-imaging sensors are available for 3D sensing but suffer from several limitations : computationally intensive, require a lighted environment (natural or man-made light source), and don't work for many scenes or regions lacking texture or with ambiguous texture. Our approach leveraged from the advanced capabilities of modern CCD camera technology and Center 6600's expertise in 3D world modeling, mapping, and analysis, using structured lighting. We have a diverse customer base for indoor mapping applications and this research extends our current technology's lifecycle and opens a new market base for outdoor 3D mapping. Applications include precision mapping, autonomous navigation, dexterous manipulation, surveillance and

  7. Inversion Techniques for Retrieving Detailed Aerosol Properties from Remote Sensing Observations: Achievements and Perspectives

    NASA Astrophysics Data System (ADS)

    Dubovik, O.

    2010-12-01

    The ability of aerosol particles to interact strongly with electromagnetic radiation makes aerosol one of most climatically important atmospheric component. Remote sensing using the same ability for characterizing properties of atmospheric aerosol is probably the most adequate observational approach for accessing aerosol effect in climatic studies. Indeed, the satellite remote sensing is unique technique allowing monitoring of time variability of the aerosol at regional and global scales. Compare to in situ and laboratory measurements, remote methods do not use aerosol sampling and allow accessing the properties of unperturbed ambient aerosol in the atmospheres. However, interpretation of the remote sensing observations involves data inversion that, in practice, often appears to be a sophisticated procedure leading to rather ambiguous results. Numerous publications offer a wide diversity of approaches suggesting somewhat different inversion methods. Such uncertainty in methodological guidance leads to excessive dependence of retrieval algorithms on the personalized input and preferences of the developer. This presentation highlights a continues effort on developing a concept clarifying the differences between various methods and outlining unified principles addressing such important aspects of inversion optimization as accounting for errors in the data used, inverting the data with different levels of accuracy, accounting for a priori and ancillary information, estimating retrieval errors, etc. The developed concept uses the principles of statistical estimation and suggests a generalized multi-term Least Square type formulation that complementarily unites advantages of a variety of practical inversion approaches, such as Phillips-Tikhonov-Twomey constrained inversion, Kalman filter, Newton-Gauss and Levenberg-Marquardt iterations, optimal estimation, etc. The concept will be demonstrated by successful implementations in several challenging aerosol remote sensing

  8. Irrigated rice area estimation using remote sensing techniques: Project's proposal and preliminary results. [Rio Grande do Sul, Brazil

    NASA Technical Reports Server (NTRS)

    Parada, N. D. J. (Principal Investigator); Deassuncao, G. V.; Moreira, M. A.; Novaes, R. A.

    1984-01-01

    The development of a methodology for annual estimates of irrigated rice crop in the State of Rio Grande do Sul, Brazil, using remote sensing techniques is proposed. The project involves interpretation, digital analysis, and sampling techniques of LANDSAT imagery. Results are discussed from a preliminary phase for identifying and evaluating irrigated rice crop areas in four counties of the State, for the crop year 1982/1983. This first phase involved just visual interpretation techniques of MSS/LANDSAT images.

  9. Remotely sensed data assimilation technique to develop machine learning models for use in water management

    NASA Astrophysics Data System (ADS)

    Zaman, Bushra

    Increasing population and water conflicts are making water management one of the most important issues of the present world. It has become absolutely necessary to find ways to manage water more efficiently. Technological advancement has introduced various techniques for data acquisition and analysis, and these tools can be used to address some of the critical issues that challenge water resource management. This research used learning machine techniques and information acquired through remote sensing, to solve problems related to soil moisture estimation and crop identification on large spatial scales. In this dissertation, solutions were proposed in three problem areas that can be important in the decision making process related to water management in irrigated systems. A data assimilation technique was used to build a learning machine model that generated soil moisture estimates commensurate with the scale of the data. The research was taken further by developing a multivariate machine learning algorithm to predict root zone soil moisture both in space and time. Further, a model was developed for supervised classification of multi-spectral reflectance data using a multi-class machine learning algorithm. The procedure was designed for classifying crops but the model is data dependent and can be used with other datasets and hence can be applied to other landcover classification problems. The dissertation compared the performance of relevance vector and the support vector machines in estimating soil moisture. A multivariate relevance vector machine algorithm was tested in the spatio-temporal prediction of soil moisture, and the multi-class relevance vector machine model was used for classifying different crop types. It was concluded that the classification scheme may uncover important data patterns contributing greatly to knowledge bases, and to scientific and medical research. The results for the soil moisture models would give a rough idea to farmers

  10. Mapping Tamarix: New techniques for field measurements, spatial modeling and remote sensing

    NASA Astrophysics Data System (ADS)

    Evangelista, Paul H.

    peak growing months. These studies demonstrate that new techniques can further our understanding of tamarisk's impacts on ecosystem processes, predict potential distribution and new invasions, and improve our ability to detect occurrence using remote sensing techniques. Collectively, the results of my studies may increase our ability to map tamarisk distributions and better quantify its impacts over multiple spatial and temporal scales.

  11. Geobotanical discrimination of ultramafic parent materials An evaluation of remote sensing techniques

    NASA Technical Reports Server (NTRS)

    Mouat, D. A.; Morrissey, L. A.; Horn, E. M.

    1984-01-01

    Color and color infrared aerial photography and imagery acquired from a Daedalus DEI-1260 multispectral airborne scanner were employed in an investigation to discriminate ultramafic rock types in a test site in southwest Oregon. An analysis of the relationships between vegetation characteristics and parent materials was performed using a vegetation classification and map developed for the project, lithologic information derived from published geologic maps of the region, and terrain information gathered in the field. Several analytical methods, including visual image analysis, band ratioing, principal components analysis, and contrast enhancement and subsequent color composite generation were used in the investigation. There was a close correspondence between vegetation types and major rock types. These were readily discriminated by the remote sensing techniques. It was found that ultramafic rock types were separable from non-ultramafic rock types and serpentine was distinguishable from non-serpentinized peridotite. Further investigations involving spectroradiometric and digital classification techniques are being performed to further identify rock types and to discriminate chromium and nickel-bearing rock types.

  12. Application of remote sensing techniques to hydrography with emphasis on bathymetry. M.S. Thesis

    NASA Technical Reports Server (NTRS)

    Dejesusparada, N. (Principal Investigator); Meireles, D. S.

    1980-01-01

    Remote sensing techniques are utilized for the determination of hydrographic characteristics, with emphasis in bathymetry. Two sensor systems were utilized: the Metric Camera Wild RC-10 and the Multispectral Scanner of LANDSAT Satellite (MSS-LANDSAT). From photographs of the metric camera, data of photographic density of points with known depth are obtained. A correlation between the variables density x depth is calculated through a regression straight line. From this line, the depth of points with known photographic density is determined. The LANDSAT MSS images are interpreted automatically in the Iterative Multispectral Analysis System (I-100) with the obtention of point subareas with the same gray level. With some simplifications done, it is assumed that the depth of a point is directly related with its gray level. Subareas with points of the same depth are then determined and isobathymetric curves are drawn. The coast line is obtained through the sensor systems already mentioned. Advantages and limitations of the techniques and of the sensor systems utilized are discussed and the results are compared with ground truth.

  13. Urban Mapping and Growth Prediction using Remote Sensing and GIS Techniques, Pune, India

    NASA Astrophysics Data System (ADS)

    Sivakumar, V.

    2014-11-01

    This study aims to map the urban area in and around Pune region between the year 1991 and 2010, and predict its probable future growth using remote sensing and GIS techniques. The Landsat TM and ETM+ satellite images of 1991, 2001 and 2010 were used for analyzing urban land use class. Urban class was extracted / mapped using supervised classification technique with maximum likelihood classifier. The accuracy assessment was carried out for classified maps. The achieved overall accuracy and Kappa statistics were 86.33 % & 0.76 respectively. Transition probability matrix and area change were obtained using different classified images. A plug-in was developed in QGIS software (open source) based on Markov Chain model algorithm for predicting probable urban growth for the future year 2021. Based on available data set, the result shows that urban area is expected to grow much higher in the year 2021 when compared to 2010. This study provides an insight into understanding of urban growth and aids in subsequent infrastructure planning, management and decision-making.

  14. High performance optical encryption based on computational ghost imaging with QR code and compressive sensing technique

    NASA Astrophysics Data System (ADS)

    Zhao, Shengmei; Wang, Le; Liang, Wenqiang; Cheng, Weiwen; Gong, Longyan

    2015-10-01

    In this paper, we propose a high performance optical encryption (OE) scheme based on computational ghost imaging (GI) with QR code and compressive sensing (CS) technique, named QR-CGI-OE scheme. N random phase screens, generated by Alice, is a secret key and be shared with its authorized user, Bob. The information is first encoded by Alice with QR code, and the QR-coded image is then encrypted with the aid of computational ghost imaging optical system. Here, measurement results from the GI optical system's bucket detector are the encrypted information and be transmitted to Bob. With the key, Bob decrypts the encrypted information to obtain the QR-coded image with GI and CS techniques, and further recovers the information by QR decoding. The experimental and numerical simulated results show that the authorized users can recover completely the original image, whereas the eavesdroppers can not acquire any information about the image even the eavesdropping ratio (ER) is up to 60% at the given measurement times. For the proposed scheme, the number of bits sent from Alice to Bob are reduced considerably and the robustness is enhanced significantly. Meantime, the measurement times in GI system is reduced and the quality of the reconstructed QR-coded image is improved.

  15. Geobotanical discrimination of ultramafic parent materials An evaluation of remote sensing techniques

    NASA Technical Reports Server (NTRS)

    Mouat, D. A.; Morrissey, L. A.; Horn, E. M.

    1984-01-01

    Color and color infrared aerial photography and imagery acquired from a Daedalus DEI-1260 multispectral airborne scanner were employed in an investigation to discriminate ultramafic rock types in a test site in southwest Oregon. An analysis of the relationships between vegetation characteristics and parent materials was performed using a vegetation classification and map developed for the project, lithologic information derived from published geologic maps of the region, and terrain information gathered in the field. Several analytical methods, including visual image analysis, band ratioing, principal components analysis, and contrast enhancement and subsequent color composite generation were used in the investigation. There was a close correspondence between vegetation types and major rock types. These were readily discriminated by the remote sensing techniques. It was found that ultramafic rock types were separable from non-ultramafic rock types and serpentine was distinguishable from non-serpentinized peridotite. Further investigations involving spectroradiometric and digital classification techniques are being performed to further identify rock types and to discriminate chromium and nickel-bearing rock types.

  16. Fingerprint detection and mapping using a phase shifted coherent gradient sensing technique.

    PubMed

    Dhanotia, Jitendra; Prakash, Satya; Bhatia, Vimal; Prakash, Shashi

    2016-07-10

    In this paper, a full field technique for mapping a latent fingerprint using a coherent gradient sensing (CGS) sensor is proposed. Collimated light from an He-Ne laser illuminates a specimen comprising a fingerprint implanted onto a reflecting surface. Reflected light from the specimen is analyzed using the CGS sensor comprising a pair of gratings. Reflected light carries information regarding the depth and orientation of furrows and ridges in the fingerprint. The topological information of the fingerprint is retrieved using four-step phase shifting interferometry. Well-defined 2D and 3D phase plots have been reconstructed to map the topography of the human fingerprint. The recorded slope data reconstructs the information regarding the separation and depth of the ridges in the latent fingerprint. The proposed technique is noninvasive and full field and does not require any kind of chemical or physical treatment. The sensor is very simple, yields interferometric sensitivity, and has the advantages of easy alignment, compactness, and low cost.

  17. Estimation of Regional Evapotranspiration Using Remotely Sensed Land Surface Temperature. Part 2: Application of Equilibrium Evaporation Model to Estimate Evapotranspiration by Remote Sensing Technique. [Japan

    NASA Technical Reports Server (NTRS)

    Kotoda, K.; Nakagawa, S.; Kai, K.; Yoshino, M. M.; Takeda, K.; Seki, K.

    1985-01-01

    In a humid region like Japan, it seems that the radiation term in the energy balance equation plays a more important role for evapotranspiration then does the vapor pressure difference between the surface and lower atmospheric boundary layer. A Priestley-Taylor type equation (equilibrium evaporation model) is used to estimate evapotranspiration. Net radiation, soil heat flux, and surface temperature data are obtained. Only temperature data obtained by remotely sensed techniques are used.

  18. Propagation Limitations in Remote Sensing.

    DTIC Science & Technology

    Contents: Multi-sensors and systems in remote sensing ; Radar sensing systems over land; Remote sensing techniques in oceanography; Influence of...propagation media and background; Infrared techniques in remote sensing ; Photography in remote sensing ; Analytical studies in remote sensing .

  19. Estimating biophysical properties of eucalyptus plantations using optical remote sensing techniques

    NASA Astrophysics Data System (ADS)

    Soares, Joao V.; Xavier, Alexandre C.; de Almeida, Auro C.; da Costa Freitas, Corina

    1998-12-01

    The feasibility of the inversion of optical remote sensing products to measure critical biophysical properties of Eucalyptus Forests at regional scales is investigated here. The biophysical variables used were leaf area Index, LAI, Diameter at Breast Height, DBH, Height and Age of Eucalyptus stands pertaining to a combination of different genetic materials (E. urophylla x E. grandis hybrids) and propagating systems (seeds or cuttings) and management system (planting and coppicing). The field sampling was done daily during 3 months, from April to June 1997, and covered 130 stands of minimum sizes of 9 hectares, within an Eucalyptus farming area of about 800 km2, centered at 19 degrees South, 42 degrees West, Brazil. The stands ranged from 12 to 84 months old. The measurements of LAI were done using two pairs of LAI-2000 (LICOR) under conditions of diffuse light. The Normalized Difference Vegetation Index, NDVI, and the Soil Adjusted Vegetation Index, SAVI, were derived from a LANDSAT-TM image acquired on June 5, 1997. Furthermore, a mixture model technique was applied to derive three new parameters: fraction of green vegetation, FGV, fraction of shadow, FSH, and fraction of soil, FS. Regression analysis were done between biophysical variables and remote sensing products. Linear correlation with coefficients of determination, R2, as high as 0.8 were found between LAI versus FGV and LAI versus SAVI, on all genetic materials. In general, SAVI was shown to give better estimates of LAI than NDVI, which is explained by the openings in the canopy as the Eucalyptus grow older. The correlation with the other biophysical variables (Height and DBH) were also shown to be significant, although the R2 ranged from 0.4 to 0.6. The correlation between FGV and SAVI was higher than 90% such that they can be used to estimate Eucalyptus biophysical parameters with the same statistical significance.

  20. Transfer of microstructure pattern of CNTs onto flexible substrate using hot press technique for sensing applications

    SciTech Connect

    Mishra, Prabhash; Harsh

    2013-08-01

    Graphical abstract: - Highlights: • Successfully transfer of microstructure patterned CNTs on PET substrate. • Demonstrate as resistor-based NH{sub 3} gas sensor in the sub-ppm range. • Excellent photodetector having instantaneous response and recovery characteristics. • An effective technique to grow and produce flexible electronic device. - Abstract: In this work, we report the successful and efficient transfer process of two- dimensional (2-D) vertically aligned carbon nanotubes (CNTs) onto polyethylene terephthalate (PET) substrate by hot pressing method with an aim to develop flexible sensor devices. Carbon nanotubes are synthesized by cold wall thermal chemical vapor deposition using patterned SiO{sub 2} substrate under low pressure. The height of the pattern of CNTs is controlled by reaction time. The entire growth and transfer process is carried out within 30 min. Strong adhesion between the nanotube and polyethylene terephthalate substrate was observed in the post-transferred case. Raman spectroscopy and scanning electron microscope (SEM) studies are used to analyze the microstructure of carbon nanotube film before and after hot pressing. This technique shows great potential for the fabrication of flexible sensing devices. We report for the first time, the application of patterned microstructure developed by this technique in the development of gas sensor and optoelectronic device. Surface resistive mode is used for detection of ammonia (NH{sub 3}) gas in the sub-ppm range. An impressive photoconducting response is also observed in the visible wavelength. The reproducibility of the sample was checked and the results indicate the possibility of use of carbon nanotube as gas sensor, photodetector, CCDs etc.

  1. Yangon River Geomorphology Identification and its Enviromental Imapacts Analsysi by Optical and Radar Sensing Techniques

    NASA Astrophysics Data System (ADS)

    Lwin, A.; Khaing, M. M.

    2012-07-01

    The Yangon river, also known as the Rangoon river, is about 40 km long (25miles), and flows from southern Myanmar as an outlet of the Irrawaddy (Ayeyarwady) river into the Ayeyarwady delta. The Yangon river drains the Pegu Mountains; both the Yangon and the Pathein rivers enter the Ayeyarwady at the delta. Fluvial geomorphology is based primarily on rivers of manageable dimensions. The emphasis is on geomorphology, sedimentology of Yangon river and techniques for their identification and management. Present techniques such as remote sensing have made it easier to investigate and interpret in details analysis of river geomorphology. In this paper, attempt has been made the complicated issues of geomorphology, sedimentation patterns and management of river system and evolution studied. The analysis was carried out for the impact of land use/ land cover (LULC) changes on stream flow patterns. The hydrologic response to intense, flood producing rainfall events bears the signatures of the geomorphic structure of the channel network and of the characteristic slope lengths defining the drainage density of the basin. The interpretation of the hydrologic response as the travel time distribution of a water particle randomly injected in a distributed manner across the landscape inspired many geomorphic insights. In 2008, Cyclone Nargis was seriously damaged to mangrove area and its biodiversity system in and around of Yangon river terraces. A combination of digital image processing techniques was employed for enhancement and classification process. It is observed from the study that middle infra red band (0.77mm - 0.86mm) is highly suitable for mapping mangroves. Two major classes of mangroves, dense and open mangroves were delineated from the digital data.

  2. Assessing grapevine canopy health in the Texas Hill Country with remote sensing and GIS techniques

    NASA Astrophysics Data System (ADS)

    Mathews, Adam J.

    Vineyards are typically managed uniformly over space, although known spatial variation exists in the performance of vines within and across vineyard blocks. Identifying spatial variability in crop performance at a large scale (one or a few vineyard blocks) is useful to vineyard managers wishing to address such variation by enacting separate management plans for differing areas of performance. Zonal management and the institution of precision viticultural practices (i.e. use of GIS and remote sensing techniques to study this spatial variation) has proven profitable for a number of reasons, namely zonal harvesting based on zone performance. This dissertation implements cutting-edge, practical, and low-cost equipment and techniques, specifically an unmanned aerial vehicle (UAV), digital cameras, and Structure from Motion (SfM), to identify spatial variation in grapevine canopy vigor at a vineyard in the Texas Hill Country American Viticultural Area. Three research objectives were addressed in this dissertation including: (1) the setup and implementation of a practical imaging system and processing methodology (digital cameras and a UAV) to produce very high spatial resolution orthophotomosaics of vineyards with visible and near-infrared bands, (2) observation of spatial and temporal variation in grapevine canopy vigor that can aid in improving vineyard management practice, and (3) development of a three-dimensional method for visualizing and quantifying vineyard canopy density. Results concluded that the low-cost tools and techniques outlined in this study provided a practical means by which to identify spatial variation in canopy vigor at the study vineyard. Of the three methods used to identify this variation, spectrally-based (NDVI), planimetrically-based (canopy extent), and three-dimensionally-derived (SfM point clouds), the latter two were most successful and would be recommended for future use. Most importantly, due to the low cost of the technology used to

  3. The research on island change detection techniques of multiple-band oriented high resolution remote sensing image

    NASA Astrophysics Data System (ADS)

    Zhang, HanSong; Wang, Difeng; Pan, Delu

    2009-07-01

    Digital change detection is the computerized process of identifying changes in the state of an object, or other earthsurface features, between different data. During the last years, a large number of change detection methods have evolved that differ widely in refinement, robustness and complexity. Some traditional change detection methods could not any more adapt to high resolution remote sensing images. The prime tendency of remote sensing change detection is from pixels level to object level. In the paper, with respect to the views of object-oriented change detection in remote sensing images, an unsupervised technique for change detection (CD) in very high geometrical resolution images is proposed, which is based on the use of morphological filters. This technique integrates the nonlinear and adaptive properties of the morphological filters with a change vector analysis (CVA) procedure. Different morphological operators are analyzed and compared with respect to the CD problem. Alternating sequential filters by reconstruction proved to be the most effective, permitting the preservation of the geometrical information of the structures in the scene while filtering the homogeneous areas. We collect two multi-temporal SPOT5 remote sensing images to analyze YangSan island change detection in this procedure as above mentioned. Experimental results confirm the effectiveness of the proposed technique. It increases the accuracy of the CD in high remote sensing change detection as compared with the standard CVA approach.

  4. Application of remote sensing techniques to measurement of windblown dust over the Columbia Plateau

    NASA Astrophysics Data System (ADS)

    Vaughan, Joseph Kevin

    The Columbia Plateau PM10 Project (CP3) is a multidisciplinary program to investigate the effect of windblown dust upon air quality within the Columbia Plateau of eastern Washington, northeastern Oregon and northern Idaho. The research presented here involves three applications of spectral remote sensing technologies in support of CP3 objectives to characterize regional vegetative cover and to determine aerosol dust burdens in the atmosphere. In the first application, data from the Advanced Very-High Resolution Radiometer (AVHRR) were used to construct a detailed vegetation map for input to an air quality modeling system for windblown dust. Composite biweekly AVHRR data were used in conjunction with soils maps to develop vegetation classes (including conservation lands), defined by modeling requirements, through a spectral clustering technique. The vegetation map was validated using both ground-truth observations and NDVI (normalized difference vegetative index) results from the entire growing season, and at multiple locations. The result is a validated vegetation map meeting the requirements of the CP3 air quality modeling system. In the second application, ground-based Multi-filter Shadow-band Radiometer (MFRSR) measurements collected at two sites were used to determine the aerosol optical thickness (AOT) through the 1998 growing season and including an April, 1998 Asian dust influx. The AOT reached a maximum of ~0.45 at 500 nm during the Asian dust event. Finally, the third application employed a contrast method to obtain AOT from two pairs of AVHRR images; results were evaluated using MFRSR-derived AOT observations. The method yielded reasonable results in one case (~0.14 compared to MFRSR AOT of 0.07) and inconclusive results in the other. This experiment was the first application of the contrast method for AOT from AVHRR imagery to a mid-latitude continental region and represents progress toward an observationally based continental dust climatology. Taken

  5. Development of Satellite Remote Sensing Techniques for Quantifying Volcanic Ash Cloud Properties

    NASA Astrophysics Data System (ADS)

    Pavolonis, Michael J.

    Novel new approaches to automatically detect and characterize volcanic ash using satellite data are presented. The Spectrally Enhanced Cloud Objects (SECO) ash detection algorithm, combines radiative transfer theory, Bayesian methods, and image processing/computer vision concepts to identify volcanic ash clouds in satellite data with skill that is generally comparable to a human expert, especially with respect to false alarm rate. The SECO method is globally applicable and can be applied to virtually any low earth orbit or geostationary satellite sensor. The new ash detection approach was quantitatively proven to be significantly more skillful than traditional pixel based approaches, including the commonly used "split-window" technique. The performance of the SECO approach is extremely promising and well suited for a variety of new and improved applications. A new approach to retrieve volcanic ash cloud properties from infrared satellite measurements was also developed. The algorithm utilizes an optimal estimation framework to retrieve ash cloud height, mass loading, and effective particle radius. Optimal estimation allows uncertainties in the measurements and forward model to be taken into account and uncertainty estimates for each of the retrieved parameters to be determined. Background atmospheric water vapor, surface temperature, and surface emissivity are explicitly accounted for on a pixel-by-pixel basis, so the algorithm is globally applicable. In addition, the ash cloud retrieval algorithm is unique because it allows the cloud temperature/height to be a free parameter. Volcanic ash clouds are a major aviation hazard. Fine-grained ash from explosive eruptions can be transported long distances (>1000 km) from the source volcano by atmospheric winds, severely disrupting aviation operations. Volcanic ash clouds are complex and the background environment in which they reside can be as well. Thus, sophisticated satellite remote sensing techniques for extracting

  6. Multiplexing technique using amplitude-modulated chirped fibre Bragg gratings with applications in two-parameter sensing

    NASA Astrophysics Data System (ADS)

    Wong, Allan C. L.; Childs, Paul A.; Peng, Gang-Ding

    2007-11-01

    A multiplexing technique using amplitude-modulated chirped fibre Bragg gratings (AMCFBGs) is presented. This technique realises the multiplexing of spectrally overlapped AMCFBGs with identical centre Bragg wavelength and bandwidth. Since it is fully compatible with the wavelength division multiplexing scheme, the number of gratings that can be multiplexed can be increased by several times. The discrete wavelet transform is used to demodulate such multiplexed signal. A wavelet denoising technique is applied to the multiplexed signal in conjunction with the demodulation. Strain measurements are performed to experimentally demonstrate the feasibility of this multiplexing technique. The absolute error and crosstalk are measured. An application to simultaneous two-parameter sensing is also demonstrated.

  7. The investigation of advanced remote sensing, radiative transfer and inversion techniques for the measurement of atmospheric constituents

    NASA Technical Reports Server (NTRS)

    Deepak, Adarsh; Wang, Pi-Huan

    1985-01-01

    The research program is documented for developing space and ground-based remote sensing techniques performed during the period from December 15, 1977 to March 15, 1985. The program involved the application of sophisticated radiative transfer codes and inversion methods to various advanced remote sensing concepts for determining atmospheric constituents, particularly aerosols. It covers detailed discussions of the solar aureole technique for monitoring columnar aerosol size distribution, and the multispectral limb scattered radiance and limb attenuated radiance (solar occultation) techniques, as well as the upwelling scattered solar radiance method for determining the aerosol and gaseous characteristics. In addition, analytical models of aerosol size distribution and simulation studies of the limb solar aureole radiance technique and the variability of ozone at high altitudes during satellite sunrise/sunset events are also described in detail.

  8. Spatial and functional characterization, identification and assessment of isolated wetlands in Alachua County, Florida, USA - GIS and remote sensing techniques

    EPA Science Inventory

    In this study, Geographic Information Systems (GIS) and remote sensing mapping techniques were developed to identify the locations of isolated wetlands in Alachua County, FL, a 2510 sq km area in north-central Florida with diverse geology and numerous isolated wetlands. The resul...

  9. Spatial and functional characterization, identification and assessment of isolated wetlands in Alachua County, Florida, USA - GIS and remote sensing techniques

    EPA Science Inventory

    In this study, Geographic Information Systems (GIS) and remote sensing mapping techniques were developed to identify the locations of isolated wetlands in Alachua County, FL, a 2510 sq km area in north-central Florida with diverse geology and numerous isolated wetlands. The resul...

  10. AHIMSA - Ad hoc histogram information measure sensing algorithm for feature selection in the context of histogram inspired clustering techniques

    NASA Technical Reports Server (NTRS)

    Dasarathy, B. V.

    1976-01-01

    An algorithm is proposed for dimensionality reduction in the context of clustering techniques based on histogram analysis. The approach is based on an evaluation of the hills and valleys in the unidimensional histograms along the different features and provides an economical means of assessing the significance of the features in a nonparametric unsupervised data environment. The method has relevance to remote sensing applications.

  11. An ameliorative technique for distributed Brillouin-based fiber optics sensing

    NASA Astrophysics Data System (ADS)

    Yang, Xing-hong; Li, Yong-qian; Yang, Zhi; Yoshino, Toshihiko

    2008-12-01

    This paper reports an ameliorative technique for distributed fiber optics sensing based on Brillouin optical time-domain reflectometry (BOTDR) and Brillouin optical-fiber time-domain analysis (BOTDA). Because the electro-optic modulator in BOTDR system has a finite extinction ratio, the pulsed laser always contains a CW component, which is hereafter called leakage. The frequency of the leakage is pv which is the same as that of the pulse, and the frequency of the Stokes wave is sv. The frequency of the acoustic wave bv at each point along the fiber matches the beat frequency of the leakage and the Stokes wave. As a result, when given an appropriate extinction ratio, the leakage will have a biggish effect on the Stokes wave, which is the same as the function between the continuous wave and the Stokes in BOTDA system. The Stokes component in spontaneous Brillouin scattering (SPBS) is amplified by the leakage along the distance when it backs to the laser end, which is the well known stimulated Brillouin scattering (SBS) phenomena. So long as the distance from the point where the SPBS engender to the laser end is long, the intensity of the SBS signal is relatively large owing to the longer amplified interval. In BOTDR system, when setting the extinction ratio at 20dB, using the SBS signal we can achieve a SNR which is approximately 5 dB greater than that of traditional system and the dynamic range performance 3 dB greater. Utilizing this new technique in BOTDR system it also has an ascendency compared with BOTDA system in respect that it access to only one end of the fiber with probe pulse light.

  12. Detecting Subsurface Agricultural Tile Drainage using GIS and Remote Sensing Technique

    NASA Astrophysics Data System (ADS)

    Budhathoki, M.; Gokkaya, K.; Tank, J. L.; Christopher, S. F.; Hanrahan, B.

    2015-12-01

    Subsurface tile drainage is a common practice in many of the row crop dominated agricultural lands in the Upper Midwest, which increases yield by making the soil more productive. It is reported that nearly half of all cropland in Indiana benefits from some sort of artificial drainage. However, subsurface tile has a significant negative impact on surface water quality by providing a fast means of transport for nutrients from fertilizers. Therefore, generating spatial data of tile drainage in the field is important and useful for agricultural landscape and hydrological studies. Subsurface tile drains in Indiana's croplands are not widely mapped. In this study, we will delineate subsurface tile drainage in agricultural land in Shatto Ditch watershed, located in Kosciusko County, Indiana. We will use geo-spatial methodology, which was purposed by earlier researchers to detect tile drainage. We will use aerial color-infrared and satellite imagery along with Light Detection and Ranging (LiDAR) data. In order to map tile lines with possible accuracy, we will use GIS-based analysis in combination with remotely sensed data. This research will be comprised of three stages: 1) masking out the potential drainage area using a decision tree rule based on land cover information, soil drainage category, surface slope, and satellite image differencing technique, 2) delineate tile lines using image processing techniques, and 3) check the accuracy of mapped tile lines with ground control points. To our knowledge, this study will be the first to check the accuracy of mapping with ground truth data. Based on the accuracy of results, we will extend the methodology to greater spatial scales. The results are expected to contribute to better characterizing and controlling water pollution sources in Indiana, which is a major environmental problem.

  13. Environmental modelling of Omerli catchment area in Istanbul, Turkey using remote sensing and GIS techniques.

    PubMed

    Coskun, H Gonca; Alparslan, Erhan

    2009-06-01

    Omerli Reservoir is one of the major drinking water reservoirs of Greater Metropolis Istanbul, providing 40% of the overall water demand. Istanbul where is one of the greatest metropolitan areas of the world with a population over 10 million and a rate of population increase about twice that of Turkey. As a result of population growth and industrial development, Omerli watershed is highly affected by the wastewater discharges from the residential areas and industrial plants. The main objective of this study is to investigate the temporal assessment of the land-use/cover of the Omerli Watershed and the water quality changes in the Reservoir. It is not possible to adequately control urbanization and other pollution sources affecting the water quality. Responses of these detrimental effects are due to rapidly increasing population, unplanned and illegal housing, and irrelevant industries at the protection zones of the watershed, together with insufficient infrastructure. The study is focused on the assessment of urbanization in relation to land use and water quality using Remote Sensing (RS) and Geographic Information Systems (GIS) techniques for all the four protection zones of the Reservoir and a time variant analyzing model is obtained. IRS-1C LISS and IRS-1C PAN, LANDSAT-5 TM satellite data of 1997, 1998, 2000, 2001 and 2006 are analyzed by confirmation through the ground truth data. RS data have been transferred into UTM coordinate system and image enhancement and classification techniques were used. Raster data were converted to vector data that belongs to study area to analyze in GIS for the purpose of planning and decision-making on protected watersheds.

  14. Comparison of remote sensing change detection techniques for assessing hurricane damage to forests.

    PubMed

    Wang, Fugui; Xu, Y Jun

    2010-03-01

    This study compared performance of four change detection algorithms with six vegetation indices derived from pre- and post-Katrina Landsat Thematic Mapper (TM) imagery and a composite of the TM bands 4, 5, and 3 in order to select an optimal remote sensing technique for identifying forestlands disturbed by Hurricane Katrina. The algorithms included univariate image differencing (UID), selective principal component analysis (PCA), change vector analysis (CVA), and postclassification comparison (PCC). The indices consisted of near-infrared to red ratios, normalized difference vegetation index, Tasseled Cap index of greenness, brightness, and wetness (TCW), and soil-adjusted vegetation index. In addition to the satellite imagery, the "ground truth" data of forest damage were also collected through field investigation and interpretation of post-Katrina aerial photos. Disturbed forests were identified by classifying the composite and the continuous change imagery with the supervised classification method. Results showed that the change detection techniques exerted apparent influence on detection results with an overall accuracy varying between 51% and 86% and a kappa statistics ranging from 0.02 to 0.72. Detected areas of disturbed forestlands were noticeable in two groups: 180,832-264,617 and 85,861-124,205 ha. The landscape of disturbed forests also displayed two unique patterns, depending upon the area group. The PCC algorithm along with the composite image contributed the highest accuracy and lowest error (0.5%) in estimating areas of disturbed forestlands. Both UID and CVA performed similarly, but caution should be taken when using selective PCA in detecting hurricane disturbance to forests. Among the six indices, TCW outperformed the other indices owing to its maximum sensitivity to forest modification. This study suggested that compared with the detection algorithms, proper selection of vegetation indices was more critical for obtaining satisfactory results.

  15. Impacts of soil sealing on potential agriculture in Egypt using remote sensing and GIS techniques

    NASA Astrophysics Data System (ADS)

    Mohamed, Elsayed Said; Belal, Abdelaziz; Shalaby, Adel

    2015-10-01

    This paper highlights the impacts of soil sealing on the agricultural soils in Nile Delta using remote sensing and GIS. The current work focuses on two aims. The first aim is to evaluate soil productivity lost to urban sprawl, which is a significant cause of soil sealing in Nile Delta. The second aim is to evaluate the Land Use and Land Cover Changes (LU LC) from 2001 to 2013 in El-Gharbia governorate as a case study. Three temporal data sets of images from two different sensors: Landsat 7 Enhanced Thematic Mapper (ETM+) with 30 m resolution acquired in 2001 and Landsat 8 acquired in 2013 with 30 m resolution, and Egypt sat acquired in 2010 with 7.8 m resolution, consequently were used. Four different supervised classification techniques (Maximum Likelihood (ML), Minimum Distance, Neural Networks (NN); and Support Vector Machine (SVM) were applied to monitor the changes of LULC in the investigated area. The results showed that the agricultural soils of the investigated area are characterized by high soil productivity depending on its chemical and physical properties. During 2010-2013, soil sealing took place on 1397 ha from the study area which characterized by soil productivity classes ranging between I and II. It is expected that the urban sprawl will be increased to 12.4% by 2020 from the study area, which means that additional 3400 ha of productive soils will be lost from agriculture. However, population growth is the most significant factor effecting urban sprawl in Nile Delta.

  16. Inverse transport problem solvers based on regularized and compressive sensing techniques

    SciTech Connect

    Cheng, Y.; Cao, L.; Wu, H.; Zhang, H.

    2012-07-01

    According to the direct exposure measurements from flash radiographic image, regularized-based method and compressive sensing (CS)-based method for inverse transport equation are presented. The linear absorption coefficients and interface locations of objects are reconstructed directly at the same time. With a large number of measurements, least-square method is utilized to complete the reconstruction. Owing to the ill-posedness of the inverse problems, regularized algorithm is employed. Tikhonov method is applied with an appropriate posterior regularization parameter to get a meaningful solution. However, it's always very costly to obtain enough measurements. With limited measurements, CS sparse reconstruction technique Orthogonal Matching Pursuit (OMP) is applied to obtain the sparse coefficients by solving an optimization problem. This paper constructs and takes the forward projection matrix rather than Gauss matrix as measurement matrix. In the CS-based algorithm, Fourier expansion and wavelet expansion are adopted to convert an underdetermined system to a well-posed system. Simulations and numerical results of regularized method with appropriate regularization parameter and that of CS-based agree well with the reference value, furthermore, both methods avoid amplifying the noise. (authors)

  17. Dynamic drought risk assessment using crop model and remote sensing techniques

    NASA Astrophysics Data System (ADS)

    Sun, H.; Su, Z.; Lv, J.; Li, L.; Wang, Y.

    2017-02-01

    Drought risk assessment is of great significance to reduce the loss of agricultural drought and ensure food security. The normally drought risk assessment method is to evaluate its exposure to the hazard and the vulnerability to extended periods of water shortage for a specific region, which is a static evaluation method. The Dynamic Drought Risk Assessment (DDRA) is to estimate the drought risk according to the crop growth and water stress conditions in real time. In this study, a DDRA method using crop model and remote sensing techniques was proposed. The crop model we employed is DeNitrification and DeComposition (DNDC) model. The drought risk was quantified by the yield losses predicted by the crop model in a scenario-based method. The crop model was re-calibrated to improve the performance by the Leaf Area Index (LAI) retrieved from MODerate Resolution Imaging Spectroradiometer (MODIS) data. And the in-situ station-based crop model was extended to assess the regional drought risk by integrating crop planted mapping. The crop planted area was extracted with extended CPPI method from MODIS data. This study was implemented and validated on maize crop in Liaoning province, China.

  18. Development of an Electrochemical Sensing Technique for Rapid Genotyping of Hepatitis B Virus

    PubMed Central

    Chen, Jinyuan; Weng, Shaohuang; Chen, Qingqiong; Liu, Ailin; Wang, Fengqing; Chen, Jing; Yi, Qiang; Liu, Qicai; Lin, Xinhua

    2014-01-01

    Objective To develop a convenient; sensitive; accurate; and economical technique for genotyping of hepatitis B viruses (HBVs). Methods The mercapto-modified B1; B2; C1; and C2-specific genotyping probes consisted of two probes for each HBV genotype that served as a double verification system. These probes were fixed on the surface of No. 1; 2; 3; and 4 gold electrodes; respectively; via Au-S bonds. Different charge generated by the binding of RuHex to phosphate groups of the DNA backbone before and after hybridization was used for distinguishing the different genotypes. Results During hybridization with genotype B; the charges detected at the No. 1 and 2 electrodes were significantly increased; while the charge at the No. 3 and 4 electrodes did not change significantly. During hybridization with genotype C; the charges detected at No. 3 and 4 electrodes were significantly increased; while the signals remained unchanged at the No. 1 and 2 electrodes. During hybridization with mixed genotypes (B and C); the charges detected at all four electrodes were significantly increased. The linear range of detection was 10−7 to 10−10 mol/L and the sensitivity for detecting mixed B (10%) or C (10%). Conclusions Rapid genotyping of HBVs based on electrochemical sensing is simple, has good specificity; and can greatly reduce the cost. This method can be used for sensitive detection of mixed B and C HBV genotypes. PMID:24658623

  19. Estimation of flooded area in the Bahr El-Jebel basin using remote sensing techniques

    NASA Astrophysics Data System (ADS)

    Shamseddin, M. A. H.; Hata, T.; Tada, A.; Bashir, M. A.; Tanakamaru, T.

    2006-07-01

    In spite of the importance of Sudd (swamp) area estimation for any hydrological project in the southern Sudan, yet, no abroad agreement on its size, due to the inaccessibility and civil war. In this study, remote sensing techniques are used to estimate the Bahr El-Jebel flooded area. MODIS-Terra (Moderate Resolution Imaging Spectroradiometer) level 1B satellite images are analyzed on basis of the unsupervised classification method. The annual mean of Bahr El-Jebel flooded area has been estimated at 20 400 km2, which is 96% of Sutcliffe and Park (1999) estimation on basis of water balance model prediction. And only, 53% of SEBAL (Surface Energy Balance Algorithm for Land) model estimation. The accuracy of the classification is 71%. The study also found the swelling and shrinkage pattern of Sudd area throughout the year is following the trends of Lake Victoria outflow patterns. The study has used two evaporation methods (open water evaporation and SEBAL model) to estimate the annual storage volume of Bahr El-Jebel River by using a water balance model. Also the storage changes due time is generated throughout the study years.

  20. Monitoring landscape response to climate change using remote sensing and GIS techniques

    SciTech Connect

    Yuhas, R.H.; Dolan, P.H.; Goetz, A.F.H. )

    1992-01-01

    Increasing concern over the threat of global warming has precipitated the need for study sites which can be scientifically monitored to detect and follow the effects of environmental landscape change. Extensive eolian dune deposits in northeastern Colorado provide an ideal study site. These dune complexes, found along the South Platte River, are currently stabilized by a thin cover of shortgrass prairie vegetation. However, stratigraphic evidence demonstrates that during at least four times in the past 10,000 years, the dunes were actively migrating across the landscape. In addition, climate models indicate that the High Plains could be one of the first areas to react to climate changes when they occur. The scaling relationships that contribute to the evolution of the landscape are nearly impossible to understand without the regional perspective that remote sensing and geographical information system (GIS) techniques provide. Imagery acquired with the NASA/JPL Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) is processed to detect the amount of sand exposed, as well as the percent vegetation cover that is currently stabilizing the dunes. Excellent discrimination is found between areas of low and no vegetation, something not possible with traditional analysis methods. Seasonal changes are also emphasized. This information is incorporated into the GIS database the authors created, which also has information on parameters that influence the landscape: elevation, soil type, surface/subsurface hydrology, etc. With these data areas that are susceptible to climate change are highlighted, but more importantly, the reasons for the susceptibility are determined using the GIS's analytical capabilities.

  1. Feasibility study for locating archaeological village sites by satellite remote sensing techniques. [multispectral photography of Alaska

    NASA Technical Reports Server (NTRS)

    Cook, J. P. (Principal Investigator); Stringer, W. J.

    1974-01-01

    The author has identified the following significant results. The objective is to determine the feasibility of detecting large Alaskan archaeological sites by satellite remote sensing techniques and mapping such sites. The approach used is to develop digital multispectral signatures of dominant surface features including vegetation, exposed soils and rock, hydrological patterns and known archaeological sites. ERTS-1 scenes are then printed out digitally in a map-like array with a letter reflecting the most appropriate classification representing each pixel. Preliminary signatures were developed and tested. It was determined that there was a need to tighten up the archaeological site signature by developing accurate signatures for all naturally-occurring vegetation and surface conditions in the vicinity of the test area. These second generation signatures have been tested by means of computer printouts and classified tape displays on the University of Alaska CDU-200 and by comparison with aerial photography. It has been concluded that the archaeological signatures now in use are as good as can be developed. Plans are to print out signatures for the entire test area and locate on topographic maps the likely locations of archaeological sites within the test area.

  2. Development of mathematical techniques for the assimilation of remote sensing data into atmospheric models

    NASA Technical Reports Server (NTRS)

    Seinfeld, J. H. (Principal Investigator)

    1982-01-01

    The problem of the assimilation of remote sensing data into mathematical models of atmospheric pollutant species was investigated. The problem is posed in terms of the matching of spatially integrated species burden measurements to the predicted three dimensional concentration fields from atmospheric diffusion models. General conditions are derived for the "reconstructability' of atmospheric concentration distributions from data typical of remote sensing applications, and a computational algorithm (filter) for the processing of remote sensing data is developed.

  3. Development of mathematical techniques for the assimilation of remote sensing data into atmospheric models

    NASA Technical Reports Server (NTRS)

    Seinfeld, J. H. (Principal Investigator)

    1982-01-01

    The problem of the assimilation of remote sensing data into mathematical models of atmospheric pollutant species was investigated. The data assimilation problem is posed in terms of the matching of spatially integrated species burden measurements to the predicted three-dimensional concentration fields from atmospheric diffusion models. General conditions were derived for the reconstructability of atmospheric concentration distributions from data typical of remote sensing applications, and a computational algorithm (filter) for the processing of remote sensing data was developed.

  4. Water impact studies. [impact of remote sensing techniques on management storage, flow, and delivery of California water

    NASA Technical Reports Server (NTRS)

    Colwell, R. N.

    1973-01-01

    An investigation has begun into the potential impact of using modern remote sensing techniques as an aid in managing, even on a day-to-day basis, the storage, flow, and delivery of water made available through the California Water Project. It is obvious that the amount of this impact depends upon the extent to which remote sensing is proven to be useful in improving predictions of both the amount of water that will be available and the amount that will be needed. It is also proposed to investigate the potential impact of remote sensing techniques as an aid in monitoring, and perhaps even in directing, changes in land use and life style being brought about through the increased availability of water in central and southern California as a result of the California Water Project. The impact of remote sensing can be of appreciable significance only if: (1) the induced changes are very substantial ones; (2) remote sensing is found, in this context, to be very useful and potentially very cost effective; and (3) resource managers adopt this new technology. Analyses will be conducted of the changing economic bases and the new land use demands resulting from increased water availability in central and southern California.

  5. Water impact studies. [impact of remote sensing techniques on management storage, flow, and delivery of California water

    NASA Technical Reports Server (NTRS)

    Colwell, R. N.

    1973-01-01

    An investigation has begun into the potential impact of using modern remote sensing techniques as an aid in managing, even on a day-to-day basis, the storage, flow, and delivery of water made available through the California Water Project. It is obvious that the amount of this impact depends upon the extent to which remote sensing is proven to be useful in improving predictions of both the amount of water that will be available and the amount that will be needed. It is also proposed to investigate the potential impact of remote sensing techniques as an aid in monitoring, and perhaps even in directing, changes in land use and life style being brought about through the increased availability of water in central and southern California as a result of the California Water Project. The impact of remote sensing can be of appreciable significance only if: (1) the induced changes are very substantial ones; (2) remote sensing is found, in this context, to be very useful and potentially very cost effective; and (3) resource managers adopt this new technology. Analyses will be conducted of the changing economic bases and the new land use demands resulting from increased water availability in central and southern California.

  6. Comparing the effects of Different Remote Sensing Techniques for Extracting Deciduous Broadleaf Phenology

    NASA Astrophysics Data System (ADS)

    Ilushin, D.; Richardson, A. D.; Toomey, M. P.; Pless, R.; Shapiro, A.

    2013-12-01

    Vegetation phenology, annual life cycles of plants, provides a key feedback with climate variability and change and is an important parameter in land surface models used to predict global climate. As such, there is a need to track the rhythm of the seasons with more detail. Common remote sensing methods used to track phenology are limited by their coarse temporal and/or spatial resolutions. Alternatively, I look to explore the usability of publicly available 'webcams' as an indicator of phenological trends. More specifically, I address the question of how this new measurement relates to that of satellite imagery, a common technique for remote sensing of phenology. I have used a subset of images from publically available, geo-referenced webcams from the Archive of Many Outdoor Scenes, a repository maintained by faculty at Washington University in St. Louis, as my test data. From the GCC (Greenness Chromatic Coordinate, or average greenness) time series produced from each of the 685 cameras used, I extract the phenological transition dates calculated for both spring and fall using curve fitting or threshold methods and compared these values to corresponding dates extracted from satellite imagery. Firstly, I look to the efficacy of reproducing reliable dates of phenological transition from data with missing information, with preliminary results showing that up to twenty percent of data can be missing while still resulting in reliable results. Next, I determine the relationship of differing date extraction methods on the webcams to find out their utility in arriving at dates that correspond with visual cues of phenological dates. These phenologically derived dates are further compared with their corresponding satellite imagery dates to find whether or not there exist prevailing biases between measurements calculated using the near-infrared and visual spectrum versus solely the visual spectrum. Lastly, the resulting information is compared geospatially to look for both

  7. Land use and land cover change detection in Isfahan, Iran using remote sensing techniques

    NASA Astrophysics Data System (ADS)

    Alavi, Niloofar

    Rapid urban growth and unprecedented rural to urban transition, along with a huge population growth are new phenomena for both high and low income countries, which started in the mid-20th century. However, urban growth rates and patterns are different in developed countries and developing ones. In less developed countries, urbanization and rural to urban transition usually takes place in an unmanaged way and they are associated with a series of socioeconomical and environmental issues and problems. Identification of the city growth trends in past decades can help urban planners and managers to minimize these negative impacts. In this research, urban growth in the city of Isfahan, Iran, is the subject of study. Isfahan the third largest city in Iran has experienced a huge urban growth and population boom during the last three decades. This transition led to the destruction of natural and agricultural lands and environmental pollutions. Historical and recent remotely sensed data, along with different remote sensing techniques and methods have been used by researchers for urban land use and land cover change detection. In this study three Landsat TM and ETM+ images of the study site, acquired in 1985, 2000 and 2009 are used. Before starting processing, radiometric normalization is done to minimize the atmospheric effects. Then, processing methods including principal component analysis (PCA), vegetation indices and supervised classification are implemented on the images. Accuracy assessment of the PCA method showed that the first PC was responsible for more than 81% of the total variance, and therefore used for analysis of PCA differencing. DeltaPC1t1-t2 shows the amount of changes in land use and land cover during the period of study. In this study ten vegetation indices were selected to be applied to the 1985 image. Accuracy assessments showed that Transformed Differencing Vegetation Index (TDVI) is the most sensitive and accurate index for mapping vegetation in arid

  8. Inter-comparison of remote sensing sensing-based shoreline mapping techniques at different coastal stretches of India.

    PubMed

    Sunder, Swathy; Ramsankaran, Raaj; Ramakrishnan, Balaji

    2017-06-01

    Many techniques are available for detection of shorelines from multispectral satellite imagery, but the choice of a certain technique for a particular study area can be tough. Hence, for the first time in literature, an inter-comparison of the most widely used shoreline mapping techniques such as Normalized Difference Water Index (NDWI), Modified NDWI (MNDWI), Improved Band Ratio (IBR) Method, and Automatic Water Extraction Index (AWEI) has been done along four different coastal stretches of India using multitemporal Landsat data. The obtained results have been validated with the high-resolution images of Cartosat-2 (panchromatic) and multispectral images from Google Earth. Performance of the above indices has been analyzed based on the statistics, such as overall accuracy, kappa coefficient, user's accuracy, producer's accuracy, and the average deviation from the reference line. It is observed that the performance of NDWI and IBR techniques are dependent on the physical characteristics of the sites, and therefore, it varies from one site to another. Results indicate that unlike these two indices, the AWEI algorithm performs consistently well followed by MNDWI irrespective of the land cover types.

  9. Applications of remote sensing techniques to county land use and flood hazard mapping

    NASA Technical Reports Server (NTRS)

    Clark, R. B.; Conn, J. S.; Miller, D. A.; Mouat, D. A.

    1975-01-01

    The application of remote sensing in Arizona is discussed. Land use and flood hazard mapping completed by the Applied Remote Sensing Program is described. Areas subject to periodic flood inundation are delineated and land use maps monitoring the growth within specific counties are provided.

  10. Real-time network traffic classification technique for wireless local area networks based on compressed sensing

    NASA Astrophysics Data System (ADS)

    Balouchestani, Mohammadreza

    2017-05-01

    Network traffic or data traffic in a Wireless Local Area Network (WLAN) is the amount of network packets moving across a wireless network from each wireless node to another wireless node, which provide the load of sampling in a wireless network. WLAN's Network traffic is the main component for network traffic measurement, network traffic control and simulation. Traffic classification technique is an essential tool for improving the Quality of Service (QoS) in different wireless networks in the complex applications such as local area networks, wireless local area networks, wireless personal area networks, wireless metropolitan area networks, and wide area networks. Network traffic classification is also an essential component in the products for QoS control in different wireless network systems and applications. Classifying network traffic in a WLAN allows to see what kinds of traffic we have in each part of the network, organize the various kinds of network traffic in each path into different classes in each path, and generate network traffic matrix in order to Identify and organize network traffic which is an important key for improving the QoS feature. To achieve effective network traffic classification, Real-time Network Traffic Classification (RNTC) algorithm for WLANs based on Compressed Sensing (CS) is presented in this paper. The fundamental goal of this algorithm is to solve difficult wireless network management problems. The proposed architecture allows reducing False Detection Rate (FDR) to 25% and Packet Delay (PD) to 15 %. The proposed architecture is also increased 10 % accuracy of wireless transmission, which provides a good background for establishing high quality wireless local area networks.

  11. Morphotectonics of the Jamini River basin, Bundelkhand Craton, Central India; using remote sensing and GIS technique

    NASA Astrophysics Data System (ADS)

    Prakash, K.; Mohanty, T.; Pati, J. K.; Singh, S.; Chaubey, K.

    2016-12-01

    Morphological and morphotectonic analyses have been used to obtain information that influence hydrographic basins, predominantly these are modifications of tectonic elements and the quantitative description of landforms. Discrimination of morphotectonic indices of active tectonics of the Jamini river basin consists the analyses of asymmetry factor, ruggedness number, basin relief, gradient, basin elongation ratio, drainage density analysis, and drainage pattern analysis, which have been completed for each drainage basin using remote sensing and GIS techniques. The Jamini river is one of the major tributaries of the Betwa river in central India. The Jamini river basin is divided into five subwatersheds viz. Jamrar, Onri, Sainam, Shahzad and Baragl subwatershed. The quantitative approach of watershed development of the Jamini river basin, and its four sixth (SW1-SW4) and one fifth (SW5) order subwatersheds, was carried out using Survey of India toposheets (parts of 54I, 54K, 54L, 54O, and 54P), Landsat 7 ETM+, ASTER (GDEM) data, and field data. The Jamini river has low bifurcation index which is a positive marker of tectonic imprint on the hydrographic network. The analyses show that the geomorphological progression of the study area was robustly influenced by tectonics. The analysis demonstrates to extensional tectonics system with the following alignments: NE-SW, NW-SE, NNE-SSW, ENE-WSW, E-W, and N-S. Three major trends are followed by lower order streams viz. NE-SW, NW-SE, and E-W directions which advocate that these tectonic trends were active at least up to the Late Pleistocene. The assessment of morphotectonic indices may be used to evaluate the control of active faults on the hydrographic system. The analysis points out westward tilting of the drainage basins with strong asymmetry in some reaches, marked elongation ratio of subwatersheds, and lower order streams having close alignment with lineaments (active faults). The study facilitated to considerate the

  12. Exploring the Whiting Features of SW Florida Through Remote Sensing Techniques and Field Measurements.

    NASA Astrophysics Data System (ADS)

    Long, J.; Hu, C.

    2016-02-01

    Floating patches of water containing high levels of calcium carbonate have been referred to as "whitings" for their bright spectral color. These in-water features are most noticeably found in the Bahama Banks region, but also in the Persian Gulf, and fresh water lakes. Although whitings have been studied for nearly a century, their process of formation is still hotly debated, whether these are the result of resuspended sediment by turbulent boundary conditions, biogenic precipitation by phytoplankton, the result of local chemistry, or something else, is still unknown. Whitings are also recurrent features, occurring throughout the year, usually with a seasonal preference. Individual events can be up to 250km2 and last for longer than one month. With such magnitude, it is important to finally understand the causes of these events, as well as their potential proxies. Though recurring, whitings are also hard to predict. Our region of interest holds newly documented whitings in a remote location, offshore from Everglades City, Florida. This study aims to combine remote sensing techniques with field measurements in order to understand a newly identified, recurring, in-water feature of SW Florida. Using daily MODIS images, a 10-year time series has been developed to evaluate the spatio-temporal variability of whitings in this area. The daily images available in near real-time also helped to plan field trips to take direct measurements of the whitings. Initial parameters were chosen based on long-standing hypotheses of whiting formation, such as those listed above, but also included spectral reflectance and backscattering as well as particle and CDOM absorption These were taken both inside and outside the whitings in order to better identify these features from remote observations. Our results provide the first study of whitings in SW Florida, adding a new multidisciplinary perspective to the world-wide phenomenon.

  13. Monitoring the coastline change of Hatiya Island in Bangladesh using remote sensing techniques

    NASA Astrophysics Data System (ADS)

    Ghosh, Manoj Kumer; Kumar, Lalit; Roy, Chandan

    2015-03-01

    A large percentage of the world's population is concentrated along the coastal zones. These environmentally sensitive areas are under intense pressure from natural processes such as erosion, accretion and natural disasters as well as anthropogenic processes such as urban growth, resource development and pollution. These threats have made the coastal zone a priority for coastline monitoring programs and sustainable coastal management. This research utilizes integrated techniques of remote sensing and geographic information system (GIS) to monitor coastline changes from 1989 to 2010 at Hatiya Island, Bangladesh. In this study, satellite images from Thematic Mapper (TM) and Enhanced Thematic Mapper (ETM) were used to quantify the spatio-temporal changes that took place in the coastal zone of Hatiya Island during the specified period. The modified normalized difference water index (MNDWI) algorithm was applied to TM (1989 and 2010) and ETM (2000) images to discriminate the land-water interface and the on-screen digitizing approach was used over the MNDWI images of 1989, 2000 and 2010 for coastline extraction. Afterwards, the extent of changes in the coastline was estimated through overlaying the digitized maps of Hatiya Island of all three years. Coastline positions were highlighted to infer the erosion/accretion sectors along the coast, and the coastline changes were calculated. The results showed that erosion was severe in the northern and western parts of the island, whereas the southern and eastern parts of the island gained land through sedimentation. Over the study period (1989-2010), this offshore island witnessed the erosion of 6476 hectares. In contrast it experienced an accretion of 9916 hectares. These erosion and accretion processes played an active role in the changes of coastline during the study period.

  14. Sand dunes monitoring using remote sensing and GIS techniques for some sites in Iraq

    NASA Astrophysics Data System (ADS)

    Fadhil, Ayad Mohammed

    This study is aimed at monitoring, mapping and assessing the sand dune encroachment in the northern central part of Iraq. The study area includes six districts suffering from the increasing prevalence of sand dunes, particularly in the recent years, which are characterized by dry weather and a reduction in rainfall averages. Remote sensing "RS" and in particular, Earth observation satellites besides Geographical Information Systems "GIS" provide significant contributions to monitoring sand dunes encroachment. Two Landsat TM images acquired on July of 1988, and July of 2009 were assembled and used to extract the research indices. Satellite image based indices; the Normalized Difference Vegetation Index "NDVI", the Tasseled Cap Wetness Indicator "TCW", the Land Surface Temperature "LST", and the Normalized Difference Sand Index "NDSI" (a new index which has been proposed in this study) with RS and GIS techniques were used for monitoring the sand dune encroachment at two sites in the northern central part of Iraq. The results showed an increase in the sand dunes accumulations by 2,020.6 km2 and 291.1 km2 throughout the 21 years from 1988 to 2009 in Baiji and Al-Aith sites in the region, respectively. Sand dunes movement rates for the same period were 1,155.9 m year-1 and 494.2 m year-1 in the two mentioned sites, respectively. The results showed that the study area in general is exposed to a high risk of sand dune encroachment. The means of soil conditioners and windbreaks has been proposed to mitigate the impacts of sand dune encroachment.

  15. Using multi-scale remote sensing techniques to quantify hillslope channel coupling in bedrock landscapes

    NASA Astrophysics Data System (ADS)

    Neely, A. B.; DiBiase, R.

    2016-12-01

    Quantifying the role of rock material properties in controlling landscape-scale erosion rates is a long-standing problem in geomorphology, yet is necessary for accurate interpretation of spatial and temporal patterns of climate and tectonics encoded in Earth's topography. In bedrock landscapes, rockfall from cliffs commonly provides the largest and strongest clasts to stream networks and, until these clasts are eroded or mobilized, can inhibit channel incision into bedrock. Hillslope and channel morphology are thought to be coupled through a connection between bedrock fracture spacing and the resulting grain size distribution of stream sediment, but field quantification of this effect in bedrock landscapes is difficult due to the inaccessibility of steep terrain and challenges characterizing heterogeneity at a range of scales. Here, we use a suite of nested field and remote sensing techniques to characterize bedrock landscape morphology in the San Jacinto and San Gabriel mountain ranges of Southern California. These ranges have similar climate, granitic bedrock, and topographic relief, but exhibit a 5-fold difference in erosion rate that we hypothesize to be a result of a contrast in bedrock fracture spacing and grain size of channel-bed material. Using airborne lidar-derived elevation point clouds, we show that bedrock cliffs in the San Jacinto Mountains are systematically steeper and taller across all spatial scales compared with those in the San Gabriel Mountains. From georeferenced high-resolution photographs taken from along exposed ridgelines, we constructed cm-scale topographic models of 100-m scale cliffs and debris chutes using Structure-from-Motion (SfM) techniques, in order to quantify (1) the extent of bedrock on hillslopes, (2) the spacing and orientation of bedrock fractures on cliffs, and (3) the grain size of rockfall deposits at the base of cliffs and in headwater channels. Our results highlight the utility of nesting SfM surveys with airborne

  16. Alignment signal extraction of the optically degenerate RSE interferometer using the wave front sensing technique

    NASA Astrophysics Data System (ADS)

    Sato, S.; Kawamura, S.

    2008-07-01

    The alignment sensing and control scheme of the resonant sideband extraction interferometer is still an unsettled issue for the next-generation gravitational wave antennas. The issue is that it is difficult to extract separate error signals for all 12 angular degrees of freedom, which is mainly arising from the complexity of the optical system and cavity 'degeneracy'. We have suggested a new sensing scheme giving reasonably separated signals which is fully compatible with the length sensing scheme. The key of this idea is to resolve the 'degeneracy' of the optical cavities. By choosing an appropriate Gouy phase for the degenerate cavities, alignment error signals with much less admixtures can be extracted.

  17. The application of remote sensing techniques to inter and intra urban analysis

    NASA Technical Reports Server (NTRS)

    Horton, F. E.

    1972-01-01

    This is an effort to assess the applicability of air and spaceborne photography toward providing data inputs to urban and regional planning, management, and research. Through evaluation of remote sensing inputs to urban change detection systems, analyzing an effort to replicate an existing urban land use data file using remotely sensed data, estimating population and dwelling units from imagery, and by identifying and evaluating a system of urban places ultilizing space photography, it was determined that remote sensing can provide data concerning land use, changes in commercial structure, data for transportation planning, housing quality, residential dynamics, and population density.

  18. Droplet sensing using small and compact high-Q planar resonator based on impedance matching technique.

    PubMed

    Lee, Hee-Jo; Yook, Jong-Gwan

    2016-09-01

    In this paper, we demonstrate the sensing feasibility of the proposed high-Q resonator using a phosphate-buffered saline droplet at microwave frequencies. In the experimental results, the resonant frequency, signal level, and Q-factor of the S21-parameter with and without a 1-μl droplet were changed to about 230 MHz, 32 dB, and 1500, respectively. The resonator system was found to be suitable for droplet sensing with a small volume due to its small and compact scheme. This resonator system is expected to play an important role in droplet sensing with different dielectric constants.

  19. Droplet sensing using small and compact high-Q planar resonator based on impedance matching technique

    NASA Astrophysics Data System (ADS)

    Lee, Hee-Jo; Yook, Jong-Gwan

    2016-09-01

    In this paper, we demonstrate the sensing feasibility of the proposed high-Q resonator using a phosphate-buffered saline droplet at microwave frequencies. In the experimental results, the resonant frequency, signal level, and Q-factor of the S21-parameter with and without a 1-μl droplet were changed to about 230 MHz, 32 dB, and 1500, respectively. The resonator system was found to be suitable for droplet sensing with a small volume due to its small and compact scheme. This resonator system is expected to play an important role in droplet sensing with different dielectric constants.

  20. Monitoring soil moisture patterns in alpine meadows using ground sensor networks and remote sensing techniques

    NASA Astrophysics Data System (ADS)

    Bertoldi, Giacomo; Brenner, Johannes; Notarnicola, Claudia; Greifeneder, Felix; Nicolini, Irene; Della Chiesa, Stefano; Niedrist, Georg; Tappeiner, Ulrike

    2015-04-01

    Soil moisture content (SMC) is a key factor for numerous processes, including runoff generation, groundwater recharge, evapotranspiration, soil respiration, and biological productivity. Understanding the controls on the spatial and temporal variability of SMC in mountain catchments is an essential step towards improving quantitative predictions of catchment hydrological processes and related ecosystem services. The interacting influences of precipitation, soil properties, vegetation, and topography on SMC and the influence of SMC patterns on runoff generation processes have been extensively investigated (Vereecken et al., 2014). However, in mountain areas, obtaining reliable SMC estimations is still challenging, because of the high variability in topography, soil and vegetation properties. In the last few years, there has been an increasing interest in the estimation of surface SMC at local scales. On the one hand, low cost wireless sensor networks provide high-resolution SMC time series. On the other hand, active remote sensing microwave techniques, such as Synthetic Aperture Radars (SARs), show promising results (Bertoldi et al. 2014). As these data provide continuous coverage of large spatial extents with high spatial resolution (10-20 m), they are particularly in demand for mountain areas. However, there are still limitations related to the fact that the SAR signal can penetrate only a few centimeters in the soil. Moreover, the signal is strongly influenced by vegetation, surface roughness and topography. In this contribution, we analyse the spatial and temporal dynamics of surface and root-zone SMC (2.5 - 5 - 25 cm depth) of alpine meadows and pastures in the Long Term Ecological Research (LTER) Area Mazia Valley (South Tyrol - Italy) with different techniques: (I) a network of 18 stations; (II) field campaigns with mobile ground sensors; (III) 20-m resolution RADARSAT2 SAR images; (IV) numerical simulations using the GEOtop hydrological model (Rigon et al

  1. Applying remote sensing and GIS techniques in solving rural county information needs

    NASA Technical Reports Server (NTRS)

    Johannsen, Chris J.; Fernandez, R. Norberto; Lozano-Garcia, D. Fabian

    1992-01-01

    The project designed was to acquaint county government officials and their clientele with remote sensing and GIS products that contain information about land conditions and land use. Other users determined through the course of this project were federal agencies working at the county level, agricultural businesses and others in need of spatial information. The specific project objectives were: (1) to investigate the feasibility of using remotely sensed data to identify and quantify specific land cover categories and conditions for purposes of tax assessment, cropland area measurements and land use evaluation; (2) to investigate the use of satellite remote sensing data as an aid in assessing soil management practices; and (3) to evaluate the use of remotely sensed data to assess soil resources and conditions which affect productivity.

  2. Wetland functional health assessment using remote sensing and other techniques: Literature search and overview. Technical memo

    SciTech Connect

    Patience, N.; Klemas, V.

    1993-03-01

    Contents: introduction; remote sensing of wetland biomass and other wetland condition indicators; conceptual approaches in wetland assessment; wetland extent and type; landscape and wetland patterns; wetland biomass and productivity; wetland vegetation; wetland habitat quality; wetland hydrology; and conclusions and recommendations.

  3. Peptides as Quorum Sensing Molecules: Measurement Techniques and Obtained Levels In vitro and In vivo

    PubMed Central

    Verbeke, Frederick; De Craemer, Severine; Debunne, Nathan; Janssens, Yorick; Wynendaele, Evelien; Van de Wiele, Christophe; De Spiegeleer, Bart

    2017-01-01

    The expression of certain bacterial genes is regulated in a cell-density dependent way, a phenomenon called quorum sensing. Both Gram-negative and Gram-positive bacteria use this type of communication, though the signal molecules (auto-inducers) used by them differ between both groups: Gram-negative bacteria use predominantly N-acyl homoserine lacton (AHL) molecules (autoinducer-1, AI-1) while Gram-positive bacteria use mainly peptides (autoinducer peptides, AIP or quorum sensing peptides). These quorum sensing molecules are not only involved in the inter-microbial communication, but can also possibly cross-talk directly or indirectly with their host. This review summarizes the currently applied analytical approaches for quorum sensing identification and quantification with additionally summarizing the experimentally found in vivo concentrations of these molecules in humans. PMID:28446863

  4. Peptides as Quorum Sensing Molecules: Measurement Techniques and Obtained Levels In vitro and In vivo.

    PubMed

    Verbeke, Frederick; De Craemer, Severine; Debunne, Nathan; Janssens, Yorick; Wynendaele, Evelien; Van de Wiele, Christophe; De Spiegeleer, Bart

    2017-01-01

    The expression of certain bacterial genes is regulated in a cell-density dependent way, a phenomenon called quorum sensing. Both Gram-negative and Gram-positive bacteria use this type of communication, though the signal molecules (auto-inducers) used by them differ between both groups: Gram-negative bacteria use predominantly N-acyl homoserine lacton (AHL) molecules (autoinducer-1, AI-1) while Gram-positive bacteria use mainly peptides (autoinducer peptides, AIP or quorum sensing peptides). These quorum sensing molecules are not only involved in the inter-microbial communication, but can also possibly cross-talk directly or indirectly with their host. This review summarizes the currently applied analytical approaches for quorum sensing identification and quantification with additionally summarizing the experimentally found in vivo concentrations of these molecules in humans.

  5. New remote sensing techniques facilitate study of earth's far-flung volcanos

    NASA Technical Reports Server (NTRS)

    Mouginis-Mark, Peter J.; Pieri, David C.

    1990-01-01

    The study of volcanos using remote sensing is discussed. The dynamics of volcanic eruptions and the interactions between volcanos and the atmosphere and ecosphere are examined. Remote sensing equipment can effectively detect mud flows, pyroclastic falls, debris avalanches, lava flows, and hazards to aircraft from eruption plumes. Consideration is given to the use of thermal IR imaging, weather satellites, and polar-orbiting satellites to study such features as lava flow, silica content, and SO2 distribution.

  6. New remote sensing techniques facilitate study of earth's far-flung volcanos

    NASA Technical Reports Server (NTRS)

    Mouginis-Mark, Peter J.; Pieri, David C.

    1990-01-01

    The study of volcanos using remote sensing is discussed. The dynamics of volcanic eruptions and the interactions between volcanos and the atmosphere and ecosphere are examined. Remote sensing equipment can effectively detect mud flows, pyroclastic falls, debris avalanches, lava flows, and hazards to aircraft from eruption plumes. Consideration is given to the use of thermal IR imaging, weather satellites, and polar-orbiting satellites to study such features as lava flow, silica content, and SO2 distribution.

  7. Multiple-image encryption by space multiplexing based on compressive sensing and the double-random phase-encoding technique.

    PubMed

    Deepan, B; Quan, C; Wang, Y; Tay, C J

    2014-07-10

    In this paper, a new multiple-image encryption and decryption technique that utilizes the compressive sensing (CS) concept along with a double-random phase encryption (DRPE) has been proposed. The space multiplexing method is employed for integrating multiple-image data. The method, which results in a nonlinear encryption system, is able to overcome the vulnerability of classical DRPE. The CS technique and space multiplexing are able to provide additional key space in the proposed method. A numerical experiment of the proposed method is implemented and the results show that the proposed method has good accuracy and is more robust than classical DRPE. The proposed system is also employed against chosen-plaintext attacks and it is found that the inclusion of compressive sensing enhances robustness against the attacks.

  8. Development of a remote sensing technique to study the hydrology of earth stock tanks on a semiarid watershed

    NASA Technical Reports Server (NTRS)

    Cluff, C. B.; Lovely, C. J.

    1974-01-01

    The stock tanks considered are relatively small earthen reservoirs, built in tributary stream channels and drainageways. A remote sensing technique is developed for obtaining quantitative data on water levels and water losses from stock tanks. Details of the used approaches are discussed along with some difficulties which would have to be overcome in order to determine the effects of the stock tanks on stream flow.

  9. Experimental validation of a millimeter wave radar technique to remotely sense atmospheric pressure at the Earth's surface

    NASA Technical Reports Server (NTRS)

    Flower, D. A.; Peckham, G. E.; Bradford, W. J.

    1984-01-01

    Experiments with a millimeter wave radar operating on the NASA CV-990 aircraft which validate the technique for remotely sensing atmospheric pressure at the Earth's surface are described. Measurements show that the precise millimeter wave observations needed to deduce pressure from space with an accuracy of 1 mb are possible, that sea surface reflection properties agree with theory and that the measured variation of differential absorption with altitude corresponds to that expected from spectroscopic models.

  10. A fast auto-focusing technique for the long focal lens TDI CCD camera in remote sensing applications

    NASA Astrophysics Data System (ADS)

    Wang, Dejiang; Ding, Xu; Zhang, Tao; Kuang, Haipeng

    2013-02-01

    The key issue in automatic focus adjustment for long focal lens TDI CCD camera in remote sensing applications is to achieve the optimum focus position as fast as possible. Existing auto-focusing techniques consume too much time as the mechanical focusing parts of the camera move in steps during the searching procedure. In this paper, we demonstrate a fast auto-focusing technique, which employs the internal optical elements and the TDI CCD itself to directly sense the deviations in back focal distance of the lens and restore the imaging system to a best-available focus. It is particularly advantageous for determination of the focus, due to that the relative motion between the TDI CCD and the focusing element can proceed without interruption. Moreover, the theoretical formulas describing the effect of imaging motion on the focusing precision and the effective focusing range are also developed. Finally, an experimental setup is constructed to evaluate the performance of the proposed technique. The results of the experiment show a ±5 μm precision of auto-focusing in a range of ±500 μmdefocus, and the searching procedure could be accomplished within 0.125 s, which leads to remarkable improvement on the real-time imaging capability for high resolution TDI CCD camera in remote sensing applications.

  11. Monitoring changes in riverine forests of Sindh-Pakistan using remote sensing and GIS techniques

    NASA Astrophysics Data System (ADS)

    Siddiqui, M. N.; Jamil, Z.; Afsar, J.

    Depletion in the forest area threatens the sustainability of agricultural production systems and en-dangers the economy of the country. Every year extensive areas of arable agricultural and forestlands are degraded and turned into wastelands over time, due to natural causes or human interventions. Depletion in forest cover, therefore, has an important impact on socio-economic development and ecological balance. High population growth rate in Pakistan is one of the main causes for rapid deterioration of the physical environment and natural resource base. In view of this, it was felt necessary to carryout landuse studies focusing on mapping the past and present conditions and the extent of forests and rangelands using satellite remote sensing (SRS) and Geographic Information System (GIS) technologies. The SRS and GIS technologies provide a possible means of monitoring and mapping the changes occurring in natural resources and the environment on a continuous basis. The riverine forests of Sindh mostly growing along the river Indus in the flood plains are spread over an area of 241,000 ha but are disappearing very rapidly. Construction of dams/barrages on the upper reaches of the river Indus for hydroelectric power and irrigation works have significantly reduced the discharge of fresh water into the lower Indus basin and as a result 100,000 acres of forests have disappeared. Furthermore, heavy floods that occurred in 1978, 1988, 1992 and 1997, altered the course of the River Indus in many places, especially in the lower reaches, this has also damaged the riverine forests of Sindh. An integrated approach involving analysis of SRS data from 1977 to 1998 and GIS technique have been used to evaluate the geographic extent and distribution of the riverine forests of Sindh and to monitor temporal changes in the forest cover between 1977 and 1990; 1990 and 1998; and 1977 and 1998. The integrated landuse forest cover maps have shown not only the temporal changes that occur in

  12. Quantifying land-cover proportions for urban runoff prediction. The advantage of distributed remote sensing techniques.

    NASA Astrophysics Data System (ADS)

    Berezowski, T.; Chormanski, J.; Batelaan, O.; Canters, F.; Van de Voorde, T.

    2012-04-01

    that, the subpixel scenario is suggested as a cost effective solution in hydrological applications; hard-classification of high resolution imagery should be used in high risk projects like flood prediction. The standard modeling approach is found not proper for urban application. Moreover, the results prove the usefulness of remote sensing techniques and their advantage over standard methods for quantifying parameters for hydrological models.

  13. Application of Remote Sensing Technique to Suspended Sediment Estimation of Pinan River, Eastern Taiwan

    NASA Astrophysics Data System (ADS)

    Wang, Y. S.; Chang, C. P.

    2014-12-01

    Because of the rapid compression between the Eurasian Plate and the Philippine Sea Plate, the Central Range of the Taiwan Island continued to quickly uplift. Moreover, because of being located in the subtropical area, Taiwan has abundant rainfall, and has distinct wet and dry season. Typhoons which almost brought violent rain, struck Taiwan average four times a year during the summer. This extreme tectonic and weather condition makes that a large number of sediments easily to be taken away from the mountainous area and output to the downstream estuary in a short time. These eroded sediments can be classified into two categories. One is bedrock sediments, and the other is suspended sediments which could be detected by the satellite remote sensing technique. In previous studies, some suspended sediment concentration (SSC) predictions were carried out by using optical satellites imagery in different areas. As we know, the more suspension sediment in water can directly reflect the higher reflectance of solar radiation. In addition, the exact form of the relationship between SSC and reflectance also depends on the mineralogy, color, and size of the sediments. Therefore, most studies developed unique relationships by relating field measurements of SSC to reflectance data from satellite imagery. The Pinan River is the largest river in eastern Taiwan. It rises in the Central Range and flows through Taitung County for 84 kilometers. Statistically, in Taiwan, more than 40 percent typhoons struck and landed from the Pinan River watershed. Abundant rainfall coupled with short channel caused plenty of sediments output from the Pinan River. In this study, we focus on Pinan River estuary by using SSC field data which was got from the Hydrological Year Book of Taiwan published by Water Resources Agency every year. Because of lack of field data, we got daily river discharge to establish the Rating Curve and predict daily SSC. Moreover, we also used FORMOSAT-2 imagery in band 3 and

  14. A wireless measurement system for three-dimensional ocular movement using the magnetic contact lens sensing technique.

    PubMed

    Young Kim, Keun; Yup Lee, Seung; Chan Kim, Hee

    2004-01-01

    A new and innovative method to measure the eye movement in a wireless manner was proposed. We verified the feasibility of our idea by fabrication and performance test of a prototype system. The prototype system consisted of a contact lens with a ring-shaped thin magnet, and eyeglasses frame-shaped PCB with analog/digital signal processing circuitry as well as four magnetoresistive sensors. This new method based on the magnetic contact lens sensing technique (MCLST) is expected to overcome all the disadvantages of the existing techniques.

  15. Use of remote sensing techniques for inventorying and planning utilization of land resources in South Dakota

    NASA Technical Reports Server (NTRS)

    Myers, V. I.; Frazee, C. J.; Rusche, A. E.; Moore, D. G.; Nelson, G. D.; Westin, F. C.

    1974-01-01

    The basic procedures for interpreting remote sensing imagery to rapidly develop general soils and land use inventories were developed and utilized in Pennington County, South Dakota. These procedures and remote sensing data products were illustrated and explained to many user groups, some of whom are interested in obtaining similar data. The general soils data were integrated with land soils data supplied by the county director of equalization to prepare a land value map. A computer print-out of this map indicating a land value for each quarter section is being used in tax reappraisal of Pennington County. The land use data provided the land use planners with the present use of land in Pennington County. Additional uses of remote sensing applications are also discussed including tornado damage assessment, hail damage evaluation, and presentation of soil and land value information on base maps assembled from ERTS-1 imagery.

  16. Development of satellite remote sensing techniques as an economic tool for forestry industry

    NASA Technical Reports Server (NTRS)

    Sader, Steven A.; Jadkowski, Mark A.

    1989-01-01

    A cooperative commercial development project designed to focus on cost-effective and practical applications of satellite remote sensing in forest management is discussed. The project, initiated in September, 1988 is being executed in three phases: (1) development of a forest resource inventory and geographic information system (GIS) updating systems; (2) testing and evaluation of remote-sensing products against forest industry specifications; and (3) integration of remote-sensing services and products in an operational setting. An advisory group represented by eleven major forest-product companies will provide direct involvement of the target market. The advisory group will focus on the following questions: Does the technology work for them? How can it be packaged to provide the needed forest-management information? Can the products and information be provided in a cost-effective manner?

  17. Remote-Sensing Technique for Determination of the Volume Absorption Coefficient of Turbid Water

    NASA Astrophysics Data System (ADS)

    Sydor, Michael; Arnone, Robert A.; Gould, Richard W., Jr.; Terrie, Gregory E.; Ladner, Sherwin D.; Wood, Christoper G.

    1998-07-01

    We use remote-sensing reflectance from particulate R rs to determine the volume absorption coefficient a of turbid water in the 400 700-nm spectral region. The calculated and measured values of a ( ) show good agreement for 0 . 5 a 10 (m 1 ). To determine R rs from a particulate, we needed to make corrections for remote-sensing reflectance owing to surface roughness S rs . We determined the average spectral distribution of S rs from the difference in total remote-sensing reflectance measured with and without polarization. The spectral shape of S rs showed an excellent fit to theoretical formulas for glare based on Rayleigh and aerosol scattering from the atmosphere.

  18. Remote sensing techniques applied to multispectral recognition of the Aranjuez pilot zone

    NASA Technical Reports Server (NTRS)

    Lemos, G. L.; Salinas, J.; Rebollo, M.

    1977-01-01

    A rectangular (7 x 14 km) area 40 km S of Madrid was remote-sensed with a three-stage recognition process. Ground truth was established in the first phase, airborne sensing with a multispectral scanner and photographic cameras were used in the second phase, and Landsat satellite data were obtained in the third phase. Agronomic and hydrological photointerpretation problems are discussed. Color, black/white, and labeled areas are displayed for crop recognition in the land-use survey; turbidity, concentrations of pollutants and natural chemicals, and densitometry of the water are considered in the evaluation of water resources.

  19. Estimation of land remote sensing satellites productivity based on the simulation technique

    NASA Astrophysics Data System (ADS)

    Kurenkov, Vladimir I.; Kucherov, Alexander S.; Yakischik, Artem A.

    2017-01-01

    The problem of estimating land remote sensing satellites productivity is considered. Here, productivity is treated as a number of separate survey objects taken in a definite time. Appropriate mathematical models have been developed. Some results obtained with the help of the software worked out in Delphi programming support environment are presented.

  20. Stomatal conductance, canopy temperature, and leaf area index estimation using remote sensing and OBIA techniques

    Treesearch

    S. Panda; D.M. Amatya; G. Hoogenboom

    2014-01-01

    Remotely sensed images including LANDSAT, SPOT, NAIP orthoimagery, and LiDAR and relevant processing tools can be used to predict plant stomatal conductance (gs), leaf area index (LAI), and canopy temperature, vegetation density, albedo, and soil moisture using vegetation indices like normalized difference vegetation index (NDVI) or soil adjusted...

  1. Theory and analysis of statistical discriminant techniques as applied to remote sensing data

    NASA Technical Reports Server (NTRS)

    Odell, P. L.

    1973-01-01

    Classification of remote earth resources sensing data according to normed exponential density statistics is reported. The use of density models appropriate for several physical situations provides an exact solution for the probabilities of classifications associated with the Bayes discriminant procedure even when the covariance matrices are unequal.

  2. Improved Target Detection in Urban Structures Using Distributed Sensing and Fast Data Acquisition Techniques

    DTIC Science & Technology

    2013-04-01

    Trans. Signal Process., vol. 57, no. 6, pp. 2275-2284, 2009. [83] A. Gurbuz, J. IVIcClellan, and W. Scott, "Compressive sensing for subsurface ... imaging using ground penetrating radar," Signal Pracess., vol. 89, no. 10, pp. 1959 -1972, 2009. [84] A. Gurbuz, J. McClellan, and W. Scott, "A

  3. Remote sensing techniques to assess active fire characteristics and post-fire effects

    Treesearch

    Leigh B. Lentile; Zachary A. Holden; Alistair M. S. Smith; Michael J. Falkowski; Andrew T. Hudak; Penelope Morgan; Sarah A. Lewis; Paul E. Gessler; Nate C. Benson

    2006-01-01

    Space and airborne sensors have been used to map area burned, assess characteristics of active fires, and characterize post-fire ecological effects. Confusion about fire intensity, fire severity, burn severity, and related terms can result in the potential misuse of the inferred information by land managers and remote sensing practitioners who require unambiguous...

  4. Strain-induced vibration and temperature sensing BOTDA system combined frequency sweeping and slope-assisted techniques.

    PubMed

    Hu, Junhui; Xia, Lan; Yang, Li; Quan, Wenwen; Zhang, Xuping

    2016-06-13

    A BOTDA sensing scheme combined frequency sweeping and slope-assisted techniques is proposed and experimentally demonstrated for simultaneously temperature and strain-induced vibration sensing. In this scheme, during sweeping Brillouin gain spectrum (BGS) for temperature measurement, we simultaneously perform FFT to the time-domain traces whose probe-pump frequency difference (PPFD) is within the FWHM of the BGS at each position of fiber, and the location and the frequency of the strain-induced vibration event can be acquired based on SA-BOTDA technique. In this way, the vibration can be continuously measured at each selected working frequency point during the BGS scanning process and multiple measurements of vibration event can be completed in one whole BGS scanning process. Meanwhile, double sidebands probe method is employed to reduce the nonlocal effects. In our experiment, a temperature event and two vibration events with the frequency of 7.00Hz or 10.00Hz are simultaneously measured near the end of 10.6km long sensing fiber in a traditional BOTDA system. The system shows 1.2°C temperature accuracy and 0.67Hz frequency resolution, as well as a 3m spatial resolution. The proposed method may find some potential applications where both the strain-induced vibration frequency and temperature are the diagnostic objects.

  5. Predicting Species Cover of Marine Macrophyte and Invertebrate Species Combining Hyperspectral Remote Sensing, Machine Learning and Regression Techniques

    PubMed Central

    Kotta, Jonne; Kutser, Tiit; Teeveer, Karolin; Vahtmäe, Ele; Pärnoja, Merli

    2013-01-01

    In order to understand biotic patterns and their changes in nature there is an obvious need for high-quality seamless measurements of such patterns. If remote sensing methods have been applied with reasonable success in terrestrial environment, their use in aquatic ecosystems still remained challenging. In the present study we combined hyperspectral remote sensing and boosted regression tree modelling (BTR), an ensemble method for statistical techniques and machine learning, in order to test their applicability in predicting macrophyte and invertebrate species cover in the optically complex seawater of the Baltic Sea. The BRT technique combined with remote sensing and traditional spatial modelling succeeded in identifying, constructing and testing functionality of abiotic environmental predictors on the coverage of benthic macrophyte and invertebrate species. Our models easily predicted a large quantity of macrophyte and invertebrate species cover and recaptured multitude of interactions between environment and biota indicating a strong potential of the method in the modelling of aquatic species in the large variety of ecosystems. PMID:23755113

  6. Multi-scale characterization of rock mass discontinuities and rock slope geometry using terrestrial remote sensing techniques

    NASA Astrophysics Data System (ADS)

    Sturzenegger, Matthieu

    Terrestrial remote sensing techniques including both digital photogrammetry and laser scanning, represent useful complements to conventional field mapping and rock mass discontinuity characterization. Several studies have highlighted practical advantages at close-range (< 300 m), including the ability to map inaccessible rock exposures and hazard reduction related to both traffic and rockfall along investigated outcrops. In addition, several authors have demonstrated their potential to provide adequate quantification of discontinuity parameters. Consequently, their incorporation into rock slope stability investigations and design projects has grown substantially over recent years. As these techniques are increasingly applied by geologists and geological engineers, it is important that their use be properly evaluated. Furthermore, guidelines to optimize their application are required in a similar manner to standardization of conventional discontinuity mapping techniques. An important thesis objective is to develop recommendations for optimal applications of terrestrial remote sensing techniques for discontinuity characterization, based on a quantitative evaluation of various registration approaches, sampling bias and extended manual mapping of 3D digital models. It is shown that simple registration networks can provide adequate measurement of discontinuity geometry for engineering purposes. The bias associated with remote sensing mapping is described. The advantages of these techniques over conventional mapping are demonstrated, including reliable discontinuity orientation measurements. Persistence can be precisely quantified instead of approximately estimated, resulting in a new class for extremely persistent discontinuities being suggested. Secondary roughness and curvature can also be considered at larger scales. The techniques are suitable for the definition of discontinuity sets, and the estimation of both trace intensity and block size/shape, if sampling bias

  7. Soil moisture measurement techniques for remote sensing ground truth: evaluation and performance test of soil moisture sensors

    NASA Astrophysics Data System (ADS)

    Tsegaye, Teferi D.; Laymon, Charles A.; Crosson, William L.; Coleman, Tommy L.; Rajbhandari, Narayan B.

    1997-12-01

    Remote sensing technology requires fast and sufficiently accurate devices to take repetitive and less destructive soil moisture measurement techniques for validation of remotely sensed data. This study was conducted at Winfred Thomas Agricultural Research Station (WTARS) in Hazel Green, Alabama. The objectives of this study were to compare volumetric water content values measured with the time domain reflectometry (TDR) and water content reflectometry (WCR) instruments to the values obtained by the standard gravimetric technique for the upper soil depth and to examine the performance of the different types of soil moisture sensors and the effect of the probe length on the accuracy of soil moisture determination. From Huntsville '96 field research, we found that the emitting depth is 5 cm or less, possibly as low as 1 cm. This suggests that, in order to validate remotely sensed data, it is necessary to have fast and sufficiently accurate instruments to take repetitive and non-destructive soil moisture measurement to measure soil moisture. Our results indicated no significance difference between the Delta-T 6 cm probe output with GSM, MESA 10 cm probe output with GSM, and WCR30 and 20 cm probe output with GSM measurements. Even though the standard gravimetric technique is very reliable to measure soil moisture content, it is relatively time consuming and very destructive. Therefore, it may not be used for repetitive measurement at exactly the same location. The different types of TDR and WCR probes we tested can be used for measuring the moisture content. Except the WCR 5 and 10 cm probes, all probes tested in this experiment provided similar results. Therefore, this probe can replace the traditional gravimetric technique as long as the proper calibration is performed for a range of soil moisture and soil types.

  8. Analytical techniques for the study of some parameters of multispectral scanner systems for remote sensing

    NASA Technical Reports Server (NTRS)

    Wiswell, E. R.; Cooper, G. R. (Principal Investigator)

    1978-01-01

    The author has identified the following significant results. The concept of average mutual information in the received spectral random process about the spectral scene was developed. Techniques amenable to implementation on a digital computer were also developed to make the required average mutual information calculations. These techniques required identification of models for the spectral response process of scenes. Stochastic modeling techniques were adapted for use. These techniques were demonstrated on empirical data from wheat and vegetation scenes.

  9. Application of remote sensing techniques for monitoring the thermal pollution of cooling-water discharge from nuclear power plant.

    PubMed

    Chen, Chuqun; Shi, Ping; Mao, Qingwen

    2003-08-01

    This article introduces a practical method to investigate thermal pollution in coastal water from satellite data. The intensity and distribution areas of thermal pollution by the heated effluent discharge from the nuclear power plant on Daya Bay, southern China were investigated by using Landsat-5 Thematic Mapper (TM) thermal band data from 1994 to 2001. A local algorithm was developed, based on sea-truth data of water surface temperature measured when the satellite passed over the study area. The local algorithm was then applied to estimate water temperature from TM data. It shows that the remote sensing technique provides an effective means to quantitatively monitor the intensity of thermal pollution and to retrieve a very detailed distribution pattern of thermal pollution in coastal waters. The remotely-sensed results of the thermal pollution can be used for environmental management of coastal waters.

  10. Coating-free reflection technique for fiber-optic sensors based on multimode interference: A temperature sensing study

    NASA Astrophysics Data System (ADS)

    Taue, Shuji; Takahashi, Tsuyoshi; Fukano, Hideki

    2016-08-01

    A novel reflection technique for use in fiber-optic sensors is investigated and applied to a multimode interference structure. The reflectivity at a fiber end face is increased with two operations. Firstly, the light intensity is increased toward the periphery of the end-face by adjusting the fiber length, which is determined theoretically. Secondly, the fiber end-face is deformed into an ellipsoid by heating it with a gas torch. The deformed shape is characterized from microscopic images. The reflected light intensity is increased by more than 10 dB as a result of controlling the fiber length and deforming its end-face. Temperature sensing was performed using the reflection-type multimode interference structure immersed in temperature-controlled silicone oil. The resulting sensitivity was 0.028 °C for a 29.60 mm sensing region, achieved without using any reflection coating.

  11. Structural, magnetic and gas sensing properties of nanosized copper ferrite powder synthesized by sol gel combustion technique

    NASA Astrophysics Data System (ADS)

    Sumangala, T. P.; Mahender, C.; Barnabe, A.; Venkataramani, N.; Prasad, Shiva

    2016-11-01

    Stoichiometric nano sized copper ferrite particles were synthesized by sol gel combustion technique. They were then calcined at various temperatures ranging from 300-800 °C and were either furnace cooled or quenched in liquid nitrogen. A high magnetisation value of 48.2 emu/g signifying the cubic phase of copper ferrite, was obtained for sample quenched to liquid nitrogen temperature from 800 °C. The ethanol sensing response of the samples was studied and a maximum of 86% response was obtained for 500 ppm ethanol in the case of a furnace cooled sample calcined at 800 °C. The chemical sensing is seen to be correlated with the c/a ratio and is best in the case of tetragonal copper ferrite.

  12. Remote-sensing based technique to account for sub-grid scale variability of land surface properties

    NASA Technical Reports Server (NTRS)

    Crosson, William L.; Laymon, Charles A.

    1995-01-01

    A method has been presented for the representation of sub-grid scale variability of surface properties within a land surface processes model. The method uses remotely-sensed data to directly or indirectly estimate probability density functions (PDF's) or key surface variables. Application of this technique in a coupled land surface-atmosphere model requires only grid-scale values of the variables of interest, obtained from low-resolution satellite imagery or surface/remote sensing data assimilation. The PDF's of each controlling surface property are superimposed on the respective grid-scale values to simulate sub-grid scale heterogeneity. Sensitivity studies will be carried out to ascertain the relative importance of the heterogeneity of several variables, and the degree to which non-linear property-process interactions impact large-scale fluxes.

  13. Utilization of combined remote sensing techniques to detect environmental variables influencing malaria vector densities in rural West Africa.

    PubMed

    Dambach, Peter; Machault, Vanessa; Lacaux, Jean-Pierre; Vignolles, Cécile; Sié, Ali; Sauerborn, Rainer

    2012-03-23

    The use of remote sensing has found its way into the field of epidemiology within the last decades. With the increased sensor resolution of recent and future satellites new possibilities emerge for high resolution risk modeling and risk mapping. A SPOT 5 satellite image, taken during the rainy season 2009 was used for calculating indices by combining the image's spectral bands. Besides the widely used Normalized Difference Vegetation Index (NDVI) other indices were tested for significant correlation against field observations. Multiple steps, including the detection of surface water, its breeding appropriateness for Anopheles and modeling of vector imagines abundance, were performed. Data collection on larvae, adult vectors and geographic parameters in the field, was amended by using remote sensing techniques to gather data on altitude (Digital Elevation Model = DEM), precipitation (Tropical Rainfall Measurement Mission = TRMM), land surface temperatures (LST). The DEM derived altitude as well as indices calculations combining the satellite's spectral bands (NDTI = Normalized Difference Turbidity Index, NDWI Mac Feeters = Normalized Difference Water Index) turned out to be reliable indicators for surface water in the local geographic setting. While Anopheles larvae abundance in habitats is driven by multiple, interconnected factors - amongst which the NDVI - and precipitation events, the presence of vector imagines was found to be correlated negatively to remotely sensed LST and positively to the cumulated amount of rainfall in the preceding 15 days and to the Normalized Difference Pond Index (NDPI) within the 500 m buffer zone around capture points. Remotely sensed geographical and meteorological factors, including precipitations, temperature, as well as vegetation, humidity and land cover indicators could be used as explanatory variables for surface water presence, larval development and imagines densities. This modeling approach based on remotely sensed

  14. Utilization of combined remote sensing techniques to detect environmental variables influencing malaria vector densities in rural West Africa

    PubMed Central

    2012-01-01

    Introduction The use of remote sensing has found its way into the field of epidemiology within the last decades. With the increased sensor resolution of recent and future satellites new possibilities emerge for high resolution risk modeling and risk mapping. Methods A SPOT 5 satellite image, taken during the rainy season 2009 was used for calculating indices by combining the image's spectral bands. Besides the widely used Normalized Difference Vegetation Index (NDVI) other indices were tested for significant correlation against field observations. Multiple steps, including the detection of surface water, its breeding appropriateness for Anopheles and modeling of vector imagines abundance, were performed. Data collection on larvae, adult vectors and geographic parameters in the field, was amended by using remote sensing techniques to gather data on altitude (Digital Elevation Model = DEM), precipitation (Tropical Rainfall Measurement Mission = TRMM), land surface temperatures (LST). Results The DEM derived altitude as well as indices calculations combining the satellite's spectral bands (NDTI = Normalized Difference Turbidity Index, NDWI Mac Feeters = Normalized Difference Water Index) turned out to be reliable indicators for surface water in the local geographic setting. While Anopheles larvae abundance in habitats is driven by multiple, interconnected factors - amongst which the NDVI - and precipitation events, the presence of vector imagines was found to be correlated negatively to remotely sensed LST and positively to the cumulated amount of rainfall in the preceding 15 days and to the Normalized Difference Pond Index (NDPI) within the 500 m buffer zone around capture points. Conclusions Remotely sensed geographical and meteorological factors, including precipitations, temperature, as well as vegetation, humidity and land cover indicators could be used as explanatory variables for surface water presence, larval development and imagines densities. This modeling

  15. Revised radiometric calibration technique for LANDSAT-4 Thematic Mapper data by the Canada Centre for Remote Sensing

    NASA Technical Reports Server (NTRS)

    Murphy, J.; Butlin, T.; Duff, P.; Fitzgerald, A.

    1984-01-01

    Observations of raw image data, raw radiometric calibration data, and background measurements extracted from the raw data streams on high density tape reveal major shortcomings in a technique proposed by the Canadian Center for Remote Sensing in 1982 for the radiometric correction of TM data. Results are presented which correlate measurements of the DC background with variations in both image data background and calibration samples. The effect on both raw data and data corrected using the earlier proposed technique is explained and the correction required for these factors as a function of individual scan line number for each detector is described. How the revised technique can be incorporated into an operational environment is demonstrated.

  16. Revised Radiometric Calibration Technique for LANDSAT-4 Thematic Mapper Data by the Canada Centre for Remote Sensing

    NASA Technical Reports Server (NTRS)

    Murphy, J.; Butlin, T.; Duff, P.; Fitzgerald, A.

    1984-01-01

    A technique for the radiometric correction of LANDSAT-4 Thematic Mapper data was proposed by the Canada Center for Remote Sensing. Subsequent detailed observations of raw image data, raw radiometric calibration data and background measurements extracted from the raw data stream on High Density Tape highlighted major shortcomings in the proposed method which if left uncorrected, can cause severe radiometric striping in the output product. Results are presented which correlate measurements of the DC background with variations in both image data background and calibration samples. The effect on both raw data and on data corrected using the earlier proposed technique is explained, and the correction required for these factors as a function of individual scan line number for each detector is described. It is shown how the revised technique can be incorporated into an operational environment.

  17. Reflectance spectroscopy - Quantitative analysis techniques for remote sensing applications. [in planetary surface geology

    NASA Technical Reports Server (NTRS)

    Clark, R. N.; Roush, T. L.

    1984-01-01

    The empirical methods and scattering theories that are important for solving remote sensing problems are among the methods for remotely sensed reflectance data analysis presently compared. In the case of the photon mean optical path length concept's implications for reflectance spectra modeling, it is shown that the mean optical path length in a particulate surface is in roughly inverse proportion to the square root of the absorption coefficient. Absorption bands, which are Gaussian in shape when plotted as true absorptance vs photon energy, are also Gaussians in apparent absorptance, although they have a smaller intensity. An apparent continuum in a reflectance spectrum is modeled as a mathematical function that is used to isolate a particular absorption feature for analysis, and it is noted that this continuum should be removed by dividing it into the reflectance spectrum.

  18. Integrating remote sensing, geographic information systems and global positioning system techniques with hydrological modeling

    NASA Astrophysics Data System (ADS)

    Thakur, Jay Krishna; Singh, Sudhir Kumar; Ekanthalu, Vicky Shettigondahalli

    2017-07-01

    Integration of remote sensing (RS), geographic information systems (GIS) and global positioning system (GPS) are emerging research areas in the field of groundwater hydrology, resource management, environmental monitoring and during emergency response. Recent advancements in the fields of RS, GIS, GPS and higher level of computation will help in providing and handling a range of data simultaneously in a time- and cost-efficient manner. This review paper deals with hydrological modeling, uses of remote sensing and GIS in hydrological modeling, models of integrations and their need and in last the conclusion. After dealing with these issues conceptually and technically, we can develop better methods and novel approaches to handle large data sets and in a better way to communicate information related with rapidly decreasing societal resources, i.e. groundwater.

  19. Laboratory analysis of techniques for remote sensing of estuarine parameters using laser excitation

    NASA Technical Reports Server (NTRS)

    Exton, R. J.; Houghton, W. M.; Esaias, W.; Harriss, R. C.; Farmer, F. H.; White, H. H.

    1983-01-01

    The theoretical concepts underlying remote sensing of estuarine parameters using laser excitation are examined. The concepts are extended to include Mie scattering as a measure of the total suspended solids and to develop the water Raman signal as an internal standard. Experimental validation of the theory was performed using backscattered laser light from a laboratory tank to simulate a remote-sensing geometry. Artificially prepared sediments and biological cultures were employed to check specific aspects of the theory under controlled conditions. Natural samples gathered from a variety of water types were also analyzed in the tank to further enhance the simulation. The results indicate that it should be possible to remotely quantify total suspended solids, dissolved organics, attenuation coefficient, chlorophyll a, and phycoerythrin in estuarine water using laser excitation.

  20. Engineering studies related to geodetic and oceanographic remote sensing using short pulsed techniques. [using laser probe

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Theoretical basis is presented for a feasibility study of measuring global ocean surface current pattern from satellites and aircraft. The analysis is supported by some preliminary laboratory experiments. Since the ultimate goal is to establish an operational routine for monitoring the global current pattern, a nondisturbing remote sensing device using a laser probe was developed. Detailed construction of the measuring system and the results of some preliminary observations are also presented.

  1. Analysis of multispectral signatures and investigation of multi-aspect remote sensing techniques

    NASA Technical Reports Server (NTRS)

    Malila, W. A.; Hieber, R. H.; Sarno, J. E.

    1974-01-01

    Two major aspects of remote sensing with multispectral scanners (MSS) are investigated. The first, multispectral signature analysis, includes the effects on classification performance of systematic variations found in the average signals received from various ground covers as well as the prediction of these variations with theoretical models of physical processes. The foremost effects studied are those associated with the time of day airborne MSS data are collected. Six data collection runs made over the same flight line in a period of five hours are analyzed, it is found that the time span significantly affects classification performance. Variations associated with scan angle also are studied. The second major topic of discussion is multi-aspect remote sensing, a new concept in remote sensing with scanners. Here, data are collected on multiple passes by a scanner that can be tilted to scan forward of the aircraft at different angles on different passes. The use of such spatially registered data to achieve improved classification of agricultural scenes is investigated and found promising. Also considered are the possibilities of extracting from multi-aspect data, information on the condition of corn canopies and the stand characteristics of forests.

  2. Use hyperspectral remote sensing technique to monitoring pine wood nomatode disease preliminary

    NASA Astrophysics Data System (ADS)

    Qin, Lin; Wang, Xianghong; Jiang, Jing; Yang, Xianchang; Ke, Daiyan; Li, Hongqun; Wang, Dingyi

    2016-10-01

    The pine wilt disease is a devastating disease of pine trees. In China, the first discoveries of the pine wilt disease on 1982 at Dr. Sun Yat-sen's Mausoleum in Nanjing. It occurred an area of 77000 hm2 in 2005, More than 1540000 pine trees deaths in the year. Many districts of Chongqing in Three Gorges Reservoir have different degrees of pine wilt disease occurrence. It is a serious threat to the ecological environment of the reservoir area. Use unmanned airship to carry high spectrum remote sensing monitoring technology to develop the study on pine wood nematode disease early diagnosis and early warning and forecasting in this study. The hyper spectral data and the digital orthophoto map data of Fuling District Yongsheng Forestry had been achieved In September 2015. Using digital image processing technology to deal with the digital orthophoto map, the number of disease tree and its distribution is automatic identified. Hyper spectral remote sensing data is processed by the spectrum comparison algorithm, and the number and distribution of disease pine trees are also obtained. Two results are compared, the distribution area of disease pine trees are basically the same, indicating that using low air remote sensing technology to monitor the pine wood nematode distribution is successful. From the results we can see that the hyper spectral data analysis results more accurate and less affected by environmental factors than digital orthophoto map analysis results, and more environment variable can be extracted, so the hyper spectral data study is future development direction.

  3. Realizing parameterless automatic classification of remote sensing imagery using ontology engineering and cyberinfrastructure techniques

    NASA Astrophysics Data System (ADS)

    Sun, Ziheng; Fang, Hui; Di, Liping; Yue, Peng

    2016-09-01

    It was an untouchable dream for remote sensing experts to realize total automatic image classification without inputting any parameter values. Experts usually spend hours and hours on tuning the input parameters of classification algorithms in order to obtain the best results. With the rapid development of knowledge engineering and cyberinfrastructure, a lot of data processing and knowledge reasoning capabilities become online accessible, shareable and interoperable. Based on these recent improvements, this paper presents an idea of parameterless automatic classification which only requires an image and automatically outputs a labeled vector. No parameters and operations are needed from endpoint consumers. An approach is proposed to realize the idea. It adopts an ontology database to store the experiences of tuning values for classifiers. A sample database is used to record training samples of image segments. Geoprocessing Web services are used as functionality blocks to finish basic classification steps. Workflow technology is involved to turn the overall image classification into a total automatic process. A Web-based prototypical system named PACS (Parameterless Automatic Classification System) is implemented. A number of images are fed into the system for evaluation purposes. The results show that the approach could automatically classify remote sensing images and have a fairly good average accuracy. It is indicated that the classified results will be more accurate if the two databases have higher quality. Once the experiences and samples in the databases are accumulated as many as an expert has, the approach should be able to get the results with similar quality to that a human expert can get. Since the approach is total automatic and parameterless, it can not only relieve remote sensing workers from the heavy and time-consuming parameter tuning work, but also significantly shorten the waiting time for consumers and facilitate them to engage in image

  4. Validation of satellite data through the remote sensing techniques and the inclusion of them into agricultural education pilot programs

    NASA Astrophysics Data System (ADS)

    Papadavid, Georgios; Kountios, Georgios; Bournaris, T.; Michailidis, Anastasios; Hadjimitsis, Diofantos G.

    2016-08-01

    Nowadays, the remote sensing techniques have a significant role in all the fields of agricultural extensions as well as agricultural economics and education but they are used more specifically in hydrology. The aim of this paper is to demonstrate the use of field spectroscopy for validation of the satellite data and how combination of remote sensing techniques and field spectroscopy can have more accurate results for irrigation purposes. For this reason vegetation indices are used which are mostly empirical equations describing vegetation parameters during the lifecycle of the crops. These numbers are generated by some combination of remote sensing bands and may have some relationship to the amount of vegetation in a given image pixel. Due to the fact that most of the commonly used vegetation indices are only concerned with red-near-infrared spectrum and can be divided to perpendicular and ratio based indices the specific goal of the research is to illustrate the effect of the atmosphere to those indices, in both categories. In this frame field spectroscopy is employed in order to derive the spectral signatures of different crops in red and infrared spectrum after a campaign of ground measurements. The main indices have been calculated using satellite images taken at interval dates during the whole lifecycle of the crops by using a GER 1500 spectro-radiomete. These indices was compared to those extracted from satellite images after applying an atmospheric correction algorithm -darkest pixel- to the satellite images at a pre-processing level so as the indices would be in comparable form to those of the ground measurements. Furthermore, there has been a research made concerning the perspectives of the inclusion of the above mentioned remote satellite techniques to agricultural education pilot programs.

  5. Artificial neural network-based estimation of the eyeball position using the magnetic contact lens sensing technique.

    PubMed

    Yup Lee, Seung; Young Kim, Keun; Chan Kim, Hee

    2005-01-01

    We have created an artificial neural network based approach for measuring eye movement using a magnetic contact lens sensing technique. The sensor array is based on using four magnetoresistive sensors. A two-layer feed-forward artificial neural network was used and an artificial eyeball model was made for the test. The neural network is trained with sample data obtained from nine spots. After training, we compared the position calculated from the developed system with the real one. The result shows that there is a good linear relationship between them. This indicates the developed system is capable of recording the position of the eyeball with a high degree of accuracy.

  6. Use of acoustic velocity methodology and remote sensing techniques to measure unsteady flow on the lower Yazoo River in Mississippi

    USGS Publications Warehouse

    Turnipseed, D. Phil; Cooper, Lance M.; Davis, Angela A.

    1998-01-01

    Methodologies have been developed for computing continuous discharge during varied, non-uniform low and medium flows on the Yazoo River at the U.S. Geological Survey streamgage below Steele Bayou near Long Lake, Mississippi, using acoustic signal processing and conventional streamgaging techniques. Procedures were also developed to compute locations of discharges during future high flow events when the stream reach is subject to hi-directional and reverse flow caused by rising stages on the Mississippi River using a combination of acoustic equipment and remote sensing technology. A description of the study area is presented. Selected results of these methods are presented for the period from March through September 1997.

  7. A technique for conditioning and calibrating force-sensing resistors for repeatable and reliable measurement of compressive force.

    PubMed

    Hall, Rick S; Desmoulin, Geoffrey T; Milner, Theodore E

    2008-12-05

    Miniature sensors that could measure forces applied by the fingers and hand without interfering with manual dexterity or range of motion would have considerable practical value in ergonomics and rehabilitation. In this study, techniques have been developed to use inexpensive pressure-sensing resistors (FSRs) to accurately measure compression force. The FSRs are converted from pressure-sensing to force-sensing devices. The effects of nonlinear response properties and dependence on loading history are compensated by signal conditioning and calibration. A fourth-order polynomial relating the applied force to the current voltage output and a linearly weighted sum of prior outputs corrects for sensor hysteresis and drift. It was found that prolonged (>20h) shear force loading caused sensor gain to change by approximately 100%. Shear loading also had the effect of eliminating shear force effects on sensor output, albeit only in the direction of shear loading. By applying prolonged shear loading in two orthogonal directions, the sensors were converted into pure compression sensors. Such preloading of the sensor is, therefore, required prior to calibration. The error in compression force after prolonged shear loading and calibration was consistently <5% from 0 to 30N and <10% from 30 to 40N. This novel method of calibrating FSRs for measuring compression force provides an inexpensive tool for biomedical and industrial design applications where measurements of finger and hand force are needed.

  8. Monitoring Chlorophyll-a with remote sensing techniques in the Tagus Estuary

    NASA Astrophysics Data System (ADS)

    Benali, A. A.

    2009-04-01

    At the present there is a major challenge to monitor coastaltransitional systems in a robust, frequent, systematic and accurate fashion. With the implementation of the Water Framework Directive (WFD), the EU Member States must monitor regularly the most relevant physical and biological parameters. The work assessed the applicability and accuracy of chl-a products from the MODIS Terra sensor in the Tagus estuary, comparing them with simulations of an ecological model (EcoWin2000), at a box scale, which was previously calibrated and validated. It is proposed a conceptual and methodological framework for future monitoring of the estuary using remote sensing data, concerning data processing, handling and integration. Typical Case 1 algorithms were pre-assessed and Case 2 empirical algorithms were regionally calibrated. The GSM and Clark algorithms had the best performances, with errors of approximately of 1.1 μg chl-a l-1 (or 20%) and correlations ranging 0.4-0.5. During calibration, the ratio R678/R551 had good correlation (r = 0.83) and low errors ( 1μg chl-a l-1), however, its evaluation showed low performances. In agreement with the pre-assessment, the GSM algorithm had the best correlation (r 0.50) and errors of approximately 0.8μg chl-a l-1. Remote sensing is a tool with high potential to assist the EU Member States to accomplish the WFD objectives, however, extensive future work is still needed. Systematic chl-a monitoring in the Tagus estuary is feasible and future work should also be aimed at developing multisource monitoring procedures integrating model, in-situ and remote sensing data thus, minimizing their individual limitations and flaws.

  9. Formulation of a minimum variance deconvolution technique for compensation of pneumatic distortion in pressure sensing devices

    NASA Technical Reports Server (NTRS)

    Whitmore, Stephen A.

    1990-01-01

    Increasingly, aircraft system designs require that aerodynamic parameters derived from pneumatic measurements be employed as control-system feedbacks. Such high frequency pressure measurements' accuracy is compromised by pressure distortion due to frictional attenuation and pneumatic resonance within the sensing system. A pneumatic distortion model is here formulated and reduced to a low-order state-variable model which retains most of the full model's dynamic characteristics. This reduced-order model is coupled with standard results from minimum variance estimation theory to develop an algorithm to compensate for pneumatic-distortion effects.

  10. A regression technique for evaluation and quantification for water quality parameters from remote sensing data

    NASA Technical Reports Server (NTRS)

    Whitlock, C. H.; Kuo, C. Y.

    1979-01-01

    The objective of this paper is to define optical physics and/or environmental conditions under which the linear multiple-regression should be applicable. An investigation of the signal-response equations is conducted and the concept is tested by application to actual remote sensing data from a laboratory experiment performed under controlled conditions. Investigation of the signal-response equations shows that the exact solution for a number of optical physics conditions is of the same form as a linearized multiple-regression equation, even if nonlinear contributions from surface reflections, atmospheric constituents, or other water pollutants are included. Limitations on achieving this type of solution are defined.

  11. Electrical Impedance Spectroscopy-Based Defect Sensing Technique in Estimating Cracks

    PubMed Central

    Zhang, Tingting; Zhou, Liangdong; Ammari, Habib; Seo, Jin Keun

    2015-01-01

    A defect sensing method based on electrical impedance spectroscopy is proposed to image cracks and reinforcing bars in concrete structures. The method utilizes the frequency-dependent behavior of thin insulating cracks: low-frequency electrical currents are blocked by insulating cracks, whereas high-frequency currents can pass through thin cracks to probe the conducting bars. From various frequency-dependent electrical impedance tomography (EIT) images, we can show its advantage in terms of detecting both thin cracks with their thickness and bars. We perform numerical simulations and phantom experiments to support the feasibility of the proposed method. PMID:26007713

  12. A technique for position sensing and improved momentum evaluation of microparticle impacts in space.

    NASA Technical Reports Server (NTRS)

    Mcdonnell, J. A. M.; Abellanas, C.

    1972-01-01

    The design of a three element piezoelectric microparticle impact sensing diaphragm is described which is sensitive to the detection of momentum propagated by the bending wave. The design achieves a sensitivity of .03 microdyn/sec and optimizes the detection of the direct-path pulse from impact relative to secondary reflections and interference from discontinuities. Measurement of the relative arrival times and the maximum amplitudes of the outputs from the three piezoelectric sensors leads to the determination of the impact position and the normally resolved impact momentum exchange. Coincidence of the signals and a partial redundancy of data leads to a very high noise discrimination.

  13. The technique flows of target detection using thermal infrared hyperspectral remote sensing

    NASA Astrophysics Data System (ADS)

    Wu, Wen Huan; Yu, Hong; Huang, Shu Tao

    2016-10-01

    In this work, the workflow of airborne thermal infrared hyperspectral technology in the actual application process is reviewed. Using the Thermal Airborne Spectrographic Imager (TASI-600), a hyperspectral thermal infrared imager manufactured by ITRES Research Limited as a case study, the work process including instrument calibration, collecting the region information of interest, data processing and analysis is elaborated. The value and effect using thermal infrared data obtained through TASI-600 is demonstrated. This work provides ideas and references for further study and investigation on the application of airborne thermal infrared hyperspectral remote sensing.

  14. Formulation of a minimum variance deconvolution technique for compensation of pneumatic distortion in pressure sensing devices

    NASA Technical Reports Server (NTRS)

    Whitmore, Stephen A.

    1990-01-01

    Increasingly, aircraft system designs require that aerodynamic parameters derived from pneumatic measurements be employed as control-system feedbacks. Such high frequency pressure measurements' accuracy is compromised by pressure distortion due to frictional attenuation and pneumatic resonance within the sensing system. A pneumatic distortion model is here formulated and reduced to a low-order state-variable model which retains most of the full model's dynamic characteristics. This reduced-order model is coupled with standard results from minimum variance estimation theory to develop an algorithm to compensate for pneumatic-distortion effects.

  15. Comparison of data inversion techniques for remotely sensed wide-angle observations of Earth emitted radiation

    NASA Technical Reports Server (NTRS)

    Green, R. N.

    1981-01-01

    The shape factor, parameter estimation, and deconvolution data analysis techniques were applied to the same set of Earth emitted radiation measurements to determine the effects of different techniques on the estimated radiation field. All three techniques are defined and their assumptions, advantages, and disadvantages are discussed. Their results are compared globally, zonally, regionally, and on a spatial spectrum basis. The standard deviations of the regional differences in the derived radiant exitance varied from 7.4 W-m/2 to 13.5 W-m/2.

  16. Advanced Sensing and Control Techniques to Facilitate Semi-Autonomous Decommissioning of Hazardous Sites - Final Report

    SciTech Connect

    Schalkoff, R.J.

    2000-12-01

    This report summarizes work after 4 years of a 3-year project (no-cost extension of the above-referenced project for a period of 12 months granted). The fourth generation of a vision sensing head for geometric and photometric scene sensing has been built and tested. Estimation algorithms for automatic sensor calibration updating under robot motion have been developed and tested. We have modified the geometry extraction component of the rendering pipeline. Laser scanning now produces highly accurate points on segmented curves. These point-curves are input to a NURBS (non-uniform rational B-spline) skinning procedure to produce interpolating surface segments. The NURBS formulation includes quadrics as a sub-class, thus this formulation allows much greater flexibility without the attendant instability of generating an entire quadric surface. We have also implemented correction for diffuse lighting and specular effects. The QRobot joint level control was extended to a complete semi-autonomous robot control system for D and D operations. The imaging and VR subsystems have been integrated and tested.

  17. Use of Geophysical and Remote Sensing Techniques During the Comprehensive Test Ban Treaty Organization's Integrated Field Exercise 2014

    NASA Astrophysics Data System (ADS)

    Labak, Peter; Sussman, Aviva; Rowlands, Aled; Chiappini, Massimo; Malich, Gregor; MacLeod, Gordon; Sankey, Peter; Sweeney, Jerry; Tuckwell, George

    2016-04-01

    The Integrated Field Exercise of 2014 (IFE14) was a field event held in the Hashemite Kingdom of Jordan (with concurrent activities in Austria) that tested the operational and technical capabilities of a Comprehensive Test Ban Treaty's (CTBT) on-site inspection (OSI). During an OSI, up to 40 inspectors search a 1000km2 inspection area for evidence of a nuclear explosion. Over 250 experts from ~50 countries were involved in IFE14 (the largest simulation of an OSI to date) and worked from a number of different directions, such as the Exercise Management and Control Teams to execute the scenario in which the exercise was played, to those participants performing as members of the Inspection Team (IT). One of the main objectives of IFE14 was to test Treaty allowed inspection techniques, including a number of geophysical and remote sensing methods. In order to develop a scenario in which the simulated exercise could be carried out, a number of physical features in the IFE14 inspection area were designed and engineered by the Scenario Task Force Group (STF) that the IT could detect by applying the geophysical and remote sensing inspection technologies, as well as other techniques allowed by the CTBT. For example, in preparation for IFE14, the STF modeled a seismic triggering event that was provided to the IT to prompt them to detect and localize aftershocks in the vicinity of a possible explosion. Similarly, the STF planted shallow targets such as borehole casings and pipes for detection by other geophysical methods. In addition, airborne technologies, which included multi-spectral imaging, were deployed such that the IT could identify freshly exposed surfaces, imported materials and other areas that had been subject to modification. This presentation will introduce the CTBT and OSI, explain the IFE14 in terms of goals specific to geophysical and remote sensing methods, and show how both the preparation for and execution of IFE14 meet those goals.

  18. Integrated Evaluation of Urban Development Suitability Based on Remote Sensing and GIS Techniques - A Case Study in Jingjinji Area, China.

    PubMed

    Dong, Jiang; Zhuang, Dafang; Xu, Xinliang; Ying, Lei

    2008-09-25

    Jingjinji area (namely Beijing, Tianjin and He Bei Province) is one of the three largest regional economic communities in China. Urban expansion has sped up in the past 20 years in this area due to the rapid economic and population growth. Evaluating the landuse suitability for urban growth on a regional scale is an urgent need, because the most suitable areas and the most suitable scale of urban growth can thus be determined accordingly. In order to meet this requirement, remote sensing and geographic information system (GIS) techniques were adopted, and an integrated evaluating model was developed supported by AHP method. The integrated urban development suitability index (UDSI) was calculated using this model. According to the UDSI result, the spatial distribution of urban development suitability and its driving forces were analyzed. Urban boundaries in 1995, 2000 and 2005, which were derived from Landsat TM/ETM+ satellite data, were overlaid on the UDSI map, and the suitable urban develop tendency in this area were discussed. The result of this study indicated that integrated evaluation of urban development could be conducted in an operational way using remote sensing data, GIS spatial analysis technique and AHP modeling method.

  19. Detection of terrain indices related to soil salinity and mapping salt-affected soils using remote sensing and geostatistical techniques.

    PubMed

    Triki Fourati, Hela; Bouaziz, Moncef; Benzina, Mourad; Bouaziz, Samir

    2017-04-01

    Traditional surveying methods of soil properties over landscapes are dramatically cost and time-consuming. Thus, remote sensing is a proper choice for monitoring environmental problem. This research aims to study the effect of environmental factors on soil salinity and to map the spatial distribution of this salinity over the southern east part of Tunisia by means of remote sensing and geostatistical techniques. For this purpose, we used Advanced Spaceborne Thermal Emission and Reflection Radiometer data to depict geomorphological parameters: elevation, slope, plan curvature (PLC), profile curvature (PRC), and aspect. Pearson correlation between these parameters and soil electrical conductivity (ECsoil) showed that mainly slope and elevation affect the concentration of salt in soil. Moreover, spectral analysis illustrated the high potential of short-wave infrared (SWIR) bands to identify saline soils. To map soil salinity in southern Tunisia, ordinary kriging (OK), minimum distance (MD) classification, and simple regression (SR) were used. The findings showed that ordinary kriging technique provides the most reliable performances to identify and classify saline soils over the study area with a root mean square error of 1.83 and mean error of 0.018.

  20. A capacitive displacement sensing technique for early detection of unbalanced loads in a washing machine.

    PubMed

    Ramasubramanian, Melur K; Tiruthani, Karthik

    2009-01-01

    Horizontal axis washing machines are water and energy efficient and becoming popular in the USA. Unlike a vertical axis washer, these do not have an agitator and depend solely on tumbling for the agitation of laundry during the wash cycle. However, due to the constant shifting of laundry during washing, the load distribution is often unbalanced during the high speed spin cycle. We present a displacement-based sensing method to detect unbalance early while the spin rate (rpm) is well below the resonance frequency so that corrective actions may be taken prior to the high speed spin cycle. Experimental and analytical characterizations of the sensor configuration are presented. Results show that the displacement sensor is more appropriate than an accelerometer for this application and offer the potential for a simple, reliable, low cost detection of unbalance.

  1. Curcumin based optical sensing of fluoride in organo-aqueous media using irradiation technique

    NASA Astrophysics Data System (ADS)

    Venkataraj, Roopa; Radhakrishnan, P.; Kailasnath, M.

    2017-06-01

    The present work describes the degradation of natural dye Curcumin in organic-aqueous media upon irradiation by a multi-wavelength source of light like mercury lamp. The presence of anions in the solution leads to degradation of Curcumin and this degradation is especially enhanced in the case of fluoride ion. The degradation of Curcumin is investigated by studying the change in its absorption and fluorescence characteristics in organoaqueous solution upon irradiation. A broad detection range of fluoride ranging from 2.3×10-6-2.22×10-3 M points to the potential of the method of visible light irradiation enabling aqueous based sensing of fluoride using Curcumin.

  2. Remote sensing techniques used in hydrocarbon exploration - A state-of-the-art review

    NASA Technical Reports Server (NTRS)

    Gonzales, R. W.

    1983-01-01

    Lintz (1972) has defined remote sensing for petroleum exploration as the detection from a distance of variations of the earth's surface or properties. Possibilities foreseen by Lintz could be realized with the Lander satellite. When used in 'phase-one' exploration programs, Landsat data have been effective in 'zeroing-in' on potential hydrocarbon traps, and later, when supplemented by more conventional exploration procedures, have led to the discovery of these resources. The present investigation is concerned with an overview of the methods utilized in 'phase-one' hydrocarbon exploration programs. The considered methods are to serve as an initial tool to aid the more conventional exploration procedures. Attention is given to visual interpretations, digital image processing, lineament analysis, surface anomalies, and geomorphology and topography.

  3. L-BOFDA: a new sensor technique for distributed Brillouin sensing

    NASA Astrophysics Data System (ADS)

    Wosniok, Aleksander; Mizuno, Yosuke; Krebber, Katerina; Nakamura, Kentaro

    2013-05-01

    We propose a new scheme of Brillouin optical frequency-domain analysis (BOFDA) for distributed fiber-optic strain and temperature sensing, named linear-configured BOFDA (L-BOFDA). In conventional loop-configured BOFDA, light injection into both ends of a fiber under test (FUT) is needed for counter-propagation of pump and probe waves. In contrast, in L-BOFDA, pump and probe waves are injected into the same end of an FUT, and the probe wave Fresnelreflected (or mirror-reflected) at the other end of the FUT is exploited; thus, one-end access is feasible. We show proof-of-concept results of distributed strain measurement in a silica single-mode fiber with L-BOFDA, and discuss the signal-to-noise ratio degradation and the benefit in developing distributed Brillouin sensors based on polymer optical fibers.

  4. Advances in atmospheric light scattering theory and remote-sensing techniques

    NASA Astrophysics Data System (ADS)

    Videen, Gorden; Sun, Wenbo; Gong, Wei

    2017-02-01

    This issue focuses especially on characterizing particles in the Earth-atmosphere system. The significant role of aerosol particles in this system was recognized in the mid-1970s [1]. Since that time, our appreciation for the role they play has only increased. It has been and continues to be one of the greatest unknown factors in the Earth-atmosphere system as evidenced by the most recent Intergovernmental Panel on Climate Change (IPCC) assessments [2]. With increased computational capabilities, in terms of both advanced algorithms and in brute-force computational power, more researchers have the tools available to address different aspects of the role of aerosols in the atmosphere. In this issue, we focus on recent advances in this topical area, especially the role of light scattering and remote sensing. This issue follows on the heels of four previous topical issues on this subject matter that have graced the pages of this journal [3-6].

  5. Mechanism analysis on biofouling detection based on optical fiber sensing technique

    NASA Astrophysics Data System (ADS)

    Ma, Huiping; Yuan, Feng; Liu, Yongmeng; Jiang, Xiuzhen

    2010-08-01

    More attention is paid to on-line monitoring of biofouling in industrial water process systems. Based on optical fiber sensing technology, biofouling detection mechanism is put forward in the paper. With biofouling formation, optical characteristics and the relation between light intensity and refractive index studied, schematic diagram of optical fiber self-referencing detecting system and technological flowchart are presented. Immunity to electromagnetic interference and other influencing factors by which the precision is great improved is also remarkable characteristic. Absorption spectrum of fluid medium molecule is measured by infrared spectrum and impurity is analyzed by character fingerprints of different liquid. Other pollutant source can be identified by means of infrared spectrum and arithmetic research of artificial neural networks (ANN) technology. It can be used in other fields such as mining, environment protection, medical treatment and transportation of oil, gas and water.

  6. Study on the techniques of valuation of ecosystem services based on remote sensing in Anxin County

    NASA Astrophysics Data System (ADS)

    Wang, Hongyan; Li, Zengyuan; Gao, Zhihai; Wang, Bengyu; Bai, Lina; Wu, Junjun; Sun, Bin; Wang, Zhibo

    2014-05-01

    The farmland ecosystem is an important component of terrestrial ecosystems and has a fundamental role in the human life. The wetland is an unique and versatile ecological system. It is important for rational development and sustainable utilization of farmland and wetland resources to study on the measurement of valuation of farmland and wetland ecosystem services. It also has important significance for improving productivity. With the rapid development of remote sensing technology, it has become a powerful tool for evaluation of the value of ecosystem services. The land cover types in Anxin County mainly was farmland and wetland, the indicator system for ecosystem services valuation was brought up based on the remote sensing data of high spatial resolution ratio(Landsat-5 TM data and SPOT-5 data), the technology system for measurement of ecosystem services value was established. The study results show that the total ecosystem services value in 2009 in Anxin was 4.216 billion yuan, and the unit area value was between 8489 yuan/hm2 and 329535 yuan/hm2. The value of natural resources, water conservation value in farmland ecosystem and eco-tourism value in wetland ecosystem were higher than the other, total of the three values reached 2.858 billion yuan, and the percentage of the total ecosystem services values in Anxin was 67.79%. Through the statistics in the nine towns and three villages of Anxin County, the juantou town has the highest services value, reached 0.736 billion yuan. Scientific and comprehensive evaluation of the ecosystem services can conducive to promoting the understanding of the importance of the ecosystem. The research results had significance to ensure the sustainable use of wetland resources and the guidance of ecological construction in Anxin County.

  7. Spatial and Temporal knowledge representation techniques for traditional machine learning classifiers applied to remote sensing data.

    NASA Astrophysics Data System (ADS)

    Cervone, G.; Kafatos, M.

    2005-12-01

    Formulating general hypotheses from limited observations is one of the fundamental principles of scientific discovery. The data mining approach consists, among others, in generating new knowledge analyzing massive amounts of data and using background knowledge. Knowledge representation is one of the fundamental topics of data mining, because the representation language dictates which algorithms to use, as well as the effective usefulness of the learned hypotheses. Programs that use richer representation languages have the advantage of generating hypotheses that are compact and easy to understand, and the disadvantage of being more complex, slower and ususally with more control parameters. On the other hand, programs that use simpler representaiton languages overcome these shortcomings, but fail to generate hypotheses that can be easily interpreted and used for problem solving and decision making. Symbolic machine learning methods, such as decision rule classifiers, use a complex representation language which can be used to describe difficult concepts, and allow to cope with spatial and temporal data, such as remote sensing data. Because data are usually collected as a sequence of observations over time and in specific locations, very often it is necessary to find relations not only in the data per se, but also in the temporal and spatial distribution of the observations. Due to the increasingly large amount of spatial and temporal data collected and analyzed in several fields such as remote sensing, geographical information systems (GIS), bioinformatics, medicine, bank transactions, etc, spatial and temporal knowledge representaion has become a problem of crucial importance. Present research investigates methods to use existing symbolic machine learning classifiers with temporal and spatial data. The data are converted in a representation language which is suitable to learn spatial and temporal relationship without modifying the existing algorithms. Results from

  8. Compressed sensing techniques for arbitrary frequency-sparse signals in structural health monitoring

    NASA Astrophysics Data System (ADS)

    Duan, Zhongdong; Kang, Jie

    2014-03-01

    Structural health monitoring requires collection of large number sample data and sometimes high frequent vibration data for detecting the damage of structures. The expensive cost for collecting the data is a big challenge. The recent proposed Compressive Sensing method enables a potentially large reduction in the sampling, and it is a way to meet the challenge. The Compressed Sensing theory requires sparse signal, meaning that the signals can be well-approximated as a linear combination of just a few elements from a known discrete basis or dictionary. The signal of structure vibration can be decomposed into a few sinusoid linear combinations in the DFT domain. Unfortunately, in most cases, the frequencies of decomposed sinusoid are arbitrary in that domain, which may not lie precisely on the discrete DFT basis or dictionary. In this case, the signal will lost its sparsity, and that makes recovery performance degrades significantly. One way to improve the sparsity of the signal is to increase the size of the dictionary, but there exists a tradeoff: the closely-spaced DFT dictionary will increase the coherence between the elements in the dictionary, which in turn decreases recovery performance. In this work we introduce three approaches for arbitrary frequency signals recovery. The first approach is the continuous basis pursuit (CBP), which reconstructs a continuous basis by introducing interpolation steps. The second approach is a semidefinite programming (SDP), which searches the sparest signal on continuous basis without establish any dictionary, enabling a very high recovery precision. The third approach is spectral iterative hard threshold (SIHT), which is based on redundant DFT dictionary and a restricted union-of-subspaces signal model, inhibiting closely spaced sinusoids. The three approaches are studied by numerical simulation. Structure vibration signal is simulated by a finite element model, and compressed measurements of the signal are taken to perform

  9. Irrigation Management with Remote Sensing Techniques. Crop Water Requirements and Biophysical Indicators

    NASA Astrophysics Data System (ADS)

    Toureiro, Célia; Serralheiro, Ricardo

    2013-04-01

    Saving water in irrigated agriculture is increasingly relevant, as the irrigation sector is in many regions the biggest water consumer, but must be a sustainable activity. Therefore, the need urges for water use control methods and water resources planning. In irrigated agriculture, the right way for saving water is constituted by the increase of efficiency in water management. This work validates procedures and methodologies with remote sensing to determine the water availability in the soil at each moment and therefore the opportunity for the application of the water volume strictly necessary to optimize crop growth (irrigation opportunity and irrigation amount). The analysis applied to the Irrigation District of Divor, Évora, having used 7 experiment plots, which are areas watered by center-pivot systems, cultivated to corn. Data were determined from multispectral and infrared images of the cultivated surface obtained by satellite or by flying unmanned platform and integrated with parameters of the atmosphere and of the crops for calculating biophysical indicators and indices of water stress in the vegetation (NDVI, Kc, Kcb, CWSI). Therefore, evapotranspiration (ETc) was estimated, with which crop water requirement was calculated, with the opportunity and the amount of irrigation water to allocate. As this information is geographic referenced, maps can be prepared with GIS technology, describing water situation and the opportunity for watering crops. If the remote images are available with enough high spatial and temporal resolution, the frequent availability of maps can serve as a basis for a farmers irrigation advice system and for the regional irrigation authority to make decisions on the irrigation management at the regional scale. This can be a significant contribute to an efficient water management technology and a sustainable irrigated agriculture. Key-Words: Remote Sensing, Vegetation Index, Crop Coefficients, Water Balance

  10. An air flow sensor for neonatal mechanical ventilation applications based on a novel fiber-optic sensing technique

    SciTech Connect

    Battista, L.; Sciuto, S. A.; Scorza, A.

    2013-03-15

    In this work, a simple and low-cost air flow sensor, based on a novel fiber-optic sensing technique has been developed for monitoring air flows rates supplied by a neonatal ventilator to support infants in intensive care units. The device is based on a fiber optic sensing technique allowing (a) the immunity to light intensity variations independent by measurand and (b) the reduction of typical shortcomings affecting all biomedical fields (electromagnetic interference and patient electrical safety). The sensing principle is based on the measurement of transversal displacement of an emitting fiber-optic cantilever due to action of air flow acting on it; the fiber tip displacement is measured by means of a photodiode linear array, placed in front of the entrance face of the emitting optical fiber in order to detect its light intensity profile. As the measurement system is based on a detection of the illumination pattern, and not on an intensity modulation technique, it results less sensitive to light intensity fluctuation independent by measurand than intensity-based sensors. The considered technique is here adopted in order to develop two different configurations for an air flow sensor suitable for the measurement of air flow rates typically occurring during mechanical ventilation of newborns: a mono-directional and a bi-directional transducer have been proposed. A mathematical model for the air flow sensor is here proposed and a static calibration of two different arrangements has been performed: a measurement range up to 3.00 Multiplication-Sign 10{sup -4} m{sup 3}/s (18.0 l/min) for the mono-directional sensor and a measurement range of {+-}3.00 Multiplication-Sign 10{sup -4} m{sup 3}/s ({+-}18.0 l/min) for the bi-directional sensor are experimentally evaluated, according to the air flow rates normally encountered during tidal breathing of infants with a mass lower than 10 kg. Experimental data of static calibration result in accordance with the proposed

  11. Flood Vulnerability Analysis of the part of Karad Region, Satara District, Maharashtra using Remote Sensing and Geographic Information System technique

    NASA Astrophysics Data System (ADS)

    Warghat, Sumedh R.; Das, Sandipan; Doad, Atul; Mali, Sagar; Moon, Vishal S.

    2012-07-01

    Karad City is situated on the bank of confluence of river Krishna & Koyana, which is severely flood prone area. The floodwaters enter the city through the roads and disrupt the infrastructure in the whole city. Furthermore, due to negligence of the authorities and unplanned growth of the city, the people living in the city have harnessed the natural flow of water by constructing unnecessary embankments in the river Koyna. Due to this reason now river koyna is flowing in the form of a narrow channel, which very easily over-flows during very minor flooding.Flood Vulnerabilty Analysis has been done for the karad region of satara district, maharashtra using remote sensing and geographic information system technique. The aim of this study is to identify flood vulnerability zone by using GIS and RS technique and an attempt has been to demonstrat the application of remote sensing and GIS in order to map flood vulnerabilty area by utilizing ArcMap, and Erdas software. Flood vulnerabilty analysis of part the Karad Regian of Satara District, Maharashtra has been carried out with the objectives - Identify the Flood Prone area in the Koyana and Krishna river basin, Calculate surface runoff and Delineate flood sensitive areas. Delineate classified hazard Map, Evaluate the Flood affected area, Prepare the Flood Vulnerability Map by utilizing Remote Sensing and GIS technique. (C.J. Kumanan;S.M. Ramasamy)The study is based on GIS and spatial technique is used for analysis and understanding of flood problem in Karad Tahsil. The flood affected areas of the different magnitude has been identified and mapped using Arc GIS software. The analysis is useful for local planning authority for identification of risk areas and taking proper decision in right moment. In the analysis causative factors for flooding in watershed are taken into account as annual rainfall, size of watershed, basin slope, drainage density of natural channels and land use. (Dinand Alkema; Farah Aziz.)This study of

  12. An air flow sensor for neonatal mechanical ventilation applications based on a novel fiber-optic sensing technique

    NASA Astrophysics Data System (ADS)

    Battista, L.; Sciuto, S. A.; Scorza, A.

    2013-03-01

    In this work, a simple and low-cost air flow sensor, based on a novel fiber-optic sensing technique has been developed for monitoring air flows rates supplied by a neonatal ventilator to support infants in intensive care units. The device is based on a fiber optic sensing technique allowing (a) the immunity to light intensity variations independent by measurand and (b) the reduction of typical shortcomings affecting all biomedical fields (electromagnetic interference and patient electrical safety). The sensing principle is based on the measurement of transversal displacement of an emitting fiber-optic cantilever due to action of air flow acting on it; the fiber tip displacement is measured by means of a photodiode linear array, placed in front of the entrance face of the emitting optical fiber in order to detect its light intensity profile. As the measurement system is based on a detection of the illumination pattern, and not on an intensity modulation technique, it results less sensitive to light intensity fluctuation independent by measurand than intensity-based sensors. The considered technique is here adopted in order to develop two different configurations for an air flow sensor suitable for the measurement of air flow rates typically occurring during mechanical ventilation of newborns: a mono-directional and a bi-directional transducer have been proposed. A mathematical model for the air flow sensor is here proposed and a static calibration of two different arrangements has been performed: a measurement range up to 3.00 × 10-4 m3/s (18.0 l/min) for the mono-directional sensor and a measurement range of ±3.00 × 10-4 m3/s (±18.0 l/min) for the bi-directional sensor are experimentally evaluated, according to the air flow rates normally encountered during tidal breathing of infants with a mass lower than 10 kg. Experimental data of static calibration result in accordance with the proposed theoretical model: for the mono-directional configuration, the

  13. An air flow sensor for neonatal mechanical ventilation applications based on a novel fiber-optic sensing technique.

    PubMed

    Battista, L; Sciuto, S A; Scorza, A

    2013-03-01

    In this work, a simple and low-cost air flow sensor, based on a novel fiber-optic sensing technique has been developed for monitoring air flows rates supplied by a neonatal ventilator to support infants in intensive care units. The device is based on a fiber optic sensing technique allowing (a) the immunity to light intensity variations independent by measurand and (b) the reduction of typical shortcomings affecting all biomedical fields (electromagnetic interference and patient electrical safety). The sensing principle is based on the measurement of transversal displacement of an emitting fiber-optic cantilever due to action of air flow acting on it; the fiber tip displacement is measured by means of a photodiode linear array, placed in front of the entrance face of the emitting optical fiber in order to detect its light intensity profile. As the measurement system is based on a detection of the illumination pattern, and not on an intensity modulation technique, it results less sensitive to light intensity fluctuation independent by measurand than intensity-based sensors. The considered technique is here adopted in order to develop two different configurations for an air flow sensor suitable for the measurement of air flow rates typically occurring during mechanical ventilation of newborns: a mono-directional and a bi-directional transducer have been proposed. A mathematical model for the air flow sensor is here proposed and a static calibration of two different arrangements has been performed: a measurement range up to 3.00 × 10(-4) m(3)∕s (18.0 l∕min) for the mono-directional sensor and a measurement range of ±3.00 × 10(-4) m(3)∕s (±18.0 l∕min) for the bi-directional sensor are experimentally evaluated, according to the air flow rates normally encountered during tidal breathing of infants with a mass lower than 10 kg. Experimental data of static calibration result in accordance with the proposed theoretical model: for the mono

  14. Scanning laser Doppler Technique for velocity profile sensing on a moving surface.

    PubMed

    Sriram, P; Hanagud, S; Craig, J; Komerath, N M

    1990-06-01

    A scanning laser Doppler technique based on Chebyshev demodulation has been developed for the rapid measurement of spatially distributed velocity profiles. Scan frequencies up to 100 Hz can be used over scan lengths up to 270 mm. The Doppler signals are processed in the conventional manner using a frequency counter. The analog velocity output from the counter is post-processed to obtain the velocity profile. The Chebyshev demodulation post-processing technique for processing the velocity signals from solid surfaces has been introduced. The data processing technique directly yields the spatial velocity distribution in approximate functional form through frequency domain analysis of the scanning LDV velocity output. Results from a rotating disk setup are presented to illustrate the concept.

  15. A Fourier-based compressed sensing technique for accelerated CT image reconstruction using first-order methods.

    PubMed

    Choi, Kihwan; Li, Ruijiang; Nam, Haewon; Xing, Lei

    2014-06-21

    As a solution to iterative CT image reconstruction, first-order methods are prominent for the large-scale capability and the fast convergence rate [Formula: see text]. In practice, the CT system matrix with a large condition number may lead to slow convergence speed despite the theoretically promising upper bound. The aim of this study is to develop a Fourier-based scaling technique to enhance the convergence speed of first-order methods applied to CT image reconstruction. Instead of working in the projection domain, we transform the projection data and construct a data fidelity model in Fourier space. Inspired by the filtered backprojection formalism, the data are appropriately weighted in Fourier space. We formulate an optimization problem based on weighted least-squares in the Fourier space and total-variation (TV) regularization in image space for parallel-beam, fan-beam and cone-beam CT geometry. To achieve the maximum computational speed, the optimization problem is solved using a fast iterative shrinkage-thresholding algorithm with backtracking line search and GPU implementation of projection/backprojection. The performance of the proposed algorithm is demonstrated through a series of digital simulation and experimental phantom studies. The results are compared with the existing TV regularized techniques based on statistics-based weighted least-squares as well as basic algebraic reconstruction technique. The proposed Fourier-based compressed sensing (CS) method significantly improves both the image quality and the convergence rate compared to the existing CS techniques.

  16. A Fourier-based compressed sensing technique for accelerated CT image reconstruction using first-order methods

    NASA Astrophysics Data System (ADS)

    Choi, Kihwan; Li, Ruijiang; Nam, Haewon; Xing, Lei

    2014-06-01

    As a solution to iterative CT image reconstruction, first-order methods are prominent for the large-scale capability and the fast convergence rate {O}(1/k^2). In practice, the CT system matrix with a large condition number may lead to slow convergence speed despite the theoretically promising upper bound. The aim of this study is to develop a Fourier-based scaling technique to enhance the convergence speed of first-order methods applied to CT image reconstruction. Instead of working in the projection domain, we transform the projection data and construct a data fidelity model in Fourier space. Inspired by the filtered backprojection formalism, the data are appropriately weighted in Fourier space. We formulate an optimization problem based on weighted least-squares in the Fourier space and total-variation (TV) regularization in image space for parallel-beam, fan-beam and cone-beam CT geometry. To achieve the maximum computational speed, the optimization problem is solved using a fast iterative shrinkage-thresholding algorithm with backtracking line search and GPU implementation of projection/backprojection. The performance of the proposed algorithm is demonstrated through a series of digital simulation and experimental phantom studies. The results are compared with the existing TV regularized techniques based on statistics-based weighted least-squares as well as basic algebraic reconstruction technique. The proposed Fourier-based compressed sensing (CS) method significantly improves both the image quality and the convergence rate compared to the existing CS techniques.

  17. Morphostructural characterization of the western edge of the Huila Plateau (SW Angola), based on remote sensing techniques

    NASA Astrophysics Data System (ADS)

    Lopes, Fernando Carlos; Pereira, Alcides José; Mantas, Vasco Manuel; Mpengo, Horácio Kativa

    2016-05-01

    Recognition of the main morphostructural features of the western edge of the Huila Plateau (SW Angola) can be done by using remote sensing techniques associated with field work. A digital elevation model (DEM) of the area was built for this purpose. This model is based on altimeter data acquired from the Aster sensor, on which image processing techniques such as enhancement techniques, contrast change and filtering were applied. Other techniques, such as RGB colour composition, were also tested. The processed satellite images were interpreted by visual process and the results were then compared with available geological maps (scale 1: 1 000 000). To facilitate both analysis and interpretation, the edge of the plateau was divided into three sectors: northern (or Chongoroi Edge), central (or Humpata Edge) and southern (or Oncocua Edge). For each sector, the main morphological aspects and main lineament systems were identified and characterized. In the specific case of the central sector, these parameters were also confirmed by field work. This study shows that the morphology of the western edge of the plateau is dominated by N50°W-N60°W, N60°E and N-S trending main tectonic systems. These results have important implications in terms of geological mapping and regional tectonics as well as in land-use planning and other areas, such as hydrogeology or geotechnics.

  18. Integrating Remote Sensing Data with Directional Two- Dimensional Wavelet Analysis and Open Geospatial Techniques for Efficient Disaster Monitoring and Management.

    PubMed

    Lin, Yun-Bin; Lin, Yu-Pin; Deng, Dong-Po; Chen, Kuan-Wei

    2008-02-19

    In Taiwan, earthquakes have long been recognized as a major cause oflandslides that are wide spread by floods brought by typhoons followed. Distinguishingbetween landslide spatial patterns in different disturbance regimes is fundamental fordisaster monitoring, management, and land-cover restoration. To circumscribe landslides,this study adopts the normalized difference vegetation index (NDVI), which can bedetermined by simply applying mathematical operations of near-infrared and visible-redspectral data immediately after remotely sensed data is acquired. In real-time disastermonitoring, the NDVI is more effective than using land-cover classifications generatedfrom remotely sensed data as land-cover classification tasks are extremely time consuming.Directional two-dimensional (2D) wavelet analysis has an advantage over traditionalspectrum analysis in that it determines localized variations along a specific direction whenidentifying dominant modes of change, and where those modes are located in multi-temporal remotely sensed images. Open geospatial techniques comprise a series ofsolutions developed based on Open Geospatial Consortium specifications that can beapplied to encode data for interoperability and develop an open geospatial service for sharing data. This study presents a novel approach and framework that uses directional 2Dwavelet analysis of real-time NDVI images to effectively identify landslide patterns andshare resulting patterns via open geospatial techniques. As a case study, this study analyzedNDVI images derived from SPOT HRV images before and after the ChiChi earthquake(7.3 on the Richter scale) that hit the Chenyulan basin in Taiwan, as well as images aftertwo large typhoons (Xangsane and Toraji) to delineate the spatial patterns of landslidescaused by major disturbances. Disturbed spatial patterns of landslides that followed theseevents were successfully delineated using 2D wavelet analysis, and results of patternrecognitions of landslides were

  19. Application of Hyperspectral Remote Sensing Techniques to Evaluate Water Quality in Turbid Coastal Waters of South Carolina.

    NASA Astrophysics Data System (ADS)

    Ali, K. A.; Ryan, K.

    2014-12-01

    Coastal and inland waters represent a diverse set of resources that support natural habitat and provide valuable ecosystem services to the human population. Conventional techniques to monitor water quality using in situ sensors and laboratory analysis of water samples can be very time- and cost-intensive. Alternatively, remote sensing techniques offer better spatial coverage and temporal resolution to accurately characterize the dynamic and unique water quality parameters. Existing remote sensing ocean color products, such as the water quality proxy chlorophyll-a, are based on ocean derived bio-optical models that are primarily calibrated in Case 1 type waters. These traditional models fail to work when applied in turbid (Case 2 type), coastal waters due to spectral interference from other associated color producing agents such as colored dissolved organic matter and suspended sediments. In this work, we introduce a novel technique for the predictive modeling of chlorophyll-a using a multivariate-based approach applied to in situ hyperspectral radiometric data collected from the coastal waters of Long Bay, South Carolina. This method uses a partial least-squares regression model to identify prominent wavelengths that are more sensitive to chlorophyll-a relative to other associated color-producing agents. The new model was able to explain 80% of the observed chlorophyll-a variability in Long Bay with RMSE = 2.03 μg/L. This approach capitalizes on the spectral advantage gained from current and future hyperspectral sensors, thus providing a more robust predicting model. This enhanced mode of water quality monitoring in marine environments will provide insight to point-sources and problem areas that may contribute to a decline in water quality. The utility of this tool is in its versatility to a diverse set of coastal waters and its use by coastal and fisheries managers with regard to recreation, regulation, economic and public health purposes.

  20. Making Quality Sense: A Guide to Quality, Tools and Techniques, Awards and the Thinking Behind Them.

    ERIC Educational Resources Information Center

    Owen, Jane

    This document is intended to guide further education colleges and work-based learning providers through some of the commonly used tools, techniques, and theories of quality management. The following are among the topics discussed: (1) various ways of defining quality; methods used by organizations to achieve quality (quality control, quality…

  1. Assessing different remote sensing techniques to detect land use/cover changes in the eastern Mediterranean

    NASA Astrophysics Data System (ADS)

    Berberoglu, S.; Akin, A.

    2009-02-01

    This paper describes different change detection techniques, including image differencing, image rationing, image regression and change vector analysis (CVA) to assess their effectiveness for detecting land use/cover change in a Mediterranean environment. Three Landsat TM scenes recorded on 7 July 1985, 27 July 1993 and 21 July 2005 were used to minimize change detection error introduced by seasonal differences. Images were geometrically, atmospherically and radiometrically corrected. The four change detection techniques were applied and an object-based supervised classification was used as a crossclassification to determine 'from-to' change which enabled assessment of the four techniques. The change vector analysis resulted in the largest overall accuracy of 75.25 and 75.55% for the 1985-1993 and 1993-2005 image pairs, respectively. The ratio yielded the least accurate results with an overall accuracy of 59.10 and 61.05% for the 1985-1993 and 1993-2005 image pairs, respectively. Different change detection algorithms have their own merits and advantages. However, the change vector analysis change detection technique was the most accurate model for handling the variability present in Mediterranean land use/cover.

  2. Multispectral imaging and sensing techniques for chlorophyll and nitrate determination in potato plants

    NASA Astrophysics Data System (ADS)

    Borhan, Md. Saidul

    Two laboratory based multispectral imaging systems were developed. The image features from color (Red, Green, and blue) and multispectral bands (550, 710, and 810 nm) were evaluated in predicting chlorophyll and nitrate contents of potato leaves grown in the greenhouse. Histogram based image features were extracted from normalized 'r' and 'g' and multispectral band images. Normalized 'r' feature ('r' average energy) was found negatively correlated (R2 = 0.90) with chlorophyll contents of leaves. Multispectral band image features were found to be linearly correlated (R2 = 0.95) to chlorophyll contents. Average prediction accuracies varied from 90.52 to 92.36% for normalized color and multispectral band image features. Average and maximum prediction accuracies were 75.15% and 99.01%, respectively, for petiole nitrate prediction using normalized 'r' image feature. Two portable, handheld multispectral spectroscopic sensing systems were also developed and evaluated to predict chlorophyll content of potato leaves. The first prototype (walking type) sensor was designed for use in outdoor condition and the second prototype (closed type) sensor was designed for use in both indoor and outdoor condition. A signal-processing algorithm was developed to process the acquired signals and to obtain the second derivative of the spectral signature. In the preliminary test, the walking-type sensor resulted in an average prediction accuracy of 83.78% using the hybrid NN model. The linear correlation between actual and predicted chlorophyll was found to be 0.95. The hybrid neural network model resulted in a correlation coefficient and average prediction accuracy of 0.93 and 77.73%, respectively, using a closed-type sensor. The walking-type multispectral sensing system was improved and evaluated to predict the chlorophyll content of potato leaves in the field. To make the sensor handy and compact, a handheld computer and associated hardware were incorporated into the design. A field test

  3. Species identification of mixed algal bloom in the Northern Arabian Sea using remote sensing techniques.

    PubMed

    Dwivedi, R; Rafeeq, M; Smitha, B R; Padmakumar, K B; Thomas, Lathika Cicily; Sanjeevan, V N; Prakash, Prince; Raman, Mini

    2015-02-01

    Oceanic waters of the Northern Arabian Sea experience massive algal blooms during winter-spring (mid Feb-end Mar), which prevail for at least for 3 months covering the entire northern half of the basin from east to west. Ship cruises were conducted during winter-spring of 2001-2012 covering different stages of the bloom to study the biogeochemistry of the region. Phytoplankton analysis indicated the presence of green tides of dinoflagellate, Noctiluca scintillans (=N. miliaris), in the oceanic waters. Our observations indicated that diatoms are coupled and often co-exist with N. scintillans, making it a mixed-species ecosystem. In this paper, we describe an approach for detection of bloom-forming algae N. scintillans and its discrimination from diatoms using Moderate Resolution Imaging Spectroradiometer (MODIS)-Aqua data in a mixed-species environment. In situ remote sensing reflectance spectra were generated using Satlantic™ hyperspectral radiometer for the bloom and non-bloom waters. Spectral shapes of the reflectance spectra for different water types were distinct, and the same were used for species identification. Scatter of points representing different phytoplankton classes on a derivative plot revealed four diverse clusters, viz. N. scintillans, diatoms, non-bloom oceanic, and non-bloom coastal waters. The criteria developed for species discrimination were implemented on MODIS data and validated using inputs from a recent ship cruise conducted in March 2013.

  4. Soil salinity mapping and hydrological drought indices assessment in arid environments based on remote sensing techniques

    NASA Astrophysics Data System (ADS)

    Elhag, Mohamed; Bahrawi, Jarbou A.

    2017-03-01

    Vegetation indices are mostly described as crop water derivatives. The normalized difference vegetation index (NDVI) is one of the oldest remote sensing applications that is widely used to evaluate crop vigor directly and crop water relationships indirectly. Recently, several NDVI derivatives were exclusively used to assess crop water relationships. Four hydrological drought indices are examined in the current research study. The water supply vegetation index (WSVI), the soil-adjusted vegetation index (SAVI), the moisture stress index (MSI) and the normalized difference infrared index (NDII) are implemented in the current study as an indirect tool to map the effect of different soil salinity levels on crop water stress in arid environments. In arid environments, such as Saudi Arabia, water resources are under pressure, especially groundwater levels. Groundwater wells are rapidly depleted due to the heavy abstraction of the reserved water. Heavy abstractions of groundwater, which exceed crop water requirements in most of the cases, are powered by high evaporation rates in the designated study area because of the long days of extremely hot summer. Landsat 8 OLI data were extensively used in the current research to obtain several vegetation indices in response to soil salinity in Wadi ad-Dawasir. Principal component analyses (PCA) and artificial neural network (ANN) analyses are complementary tools used to understand the regression pattern of the hydrological drought indices in the designated study area.

  5. Fast and low-dose computed laminography using compressive sensing based technique

    SciTech Connect

    Abbas, Sajid Park, Miran Cho, Seungryong

    2015-03-31

    Computed laminography (CL) is well known for inspecting microstructures in the materials, weldments and soldering defects in high density packed components or multilayer printed circuit boards. The overload problem on x-ray tube and gross failure of the radio-sensitive electronics devices during a scan are among important issues in CL which needs to be addressed. The sparse-view CL can be one of the viable option to overcome such issues. In this work a numerical aluminum welding phantom was simulated to collect sparsely sampled projection data at only 40 views using a conventional CL scanning scheme i.e. oblique scan. A compressive-sensing inspired total-variation (TV) minimization algorithm was utilized to reconstruct the images. It is found that the images reconstructed using sparse view data are visually comparable with the images reconstructed using full scan data set i.e. at 360 views on regular interval. We have quantitatively confirmed that tiny structures such as copper and tungsten slags, and copper flakes in the reconstructed images from sparsely sampled data are comparable with the corresponding structure present in the fully sampled data case. A blurring effect can be seen near the edges of few pores at the bottom of the reconstructed images from sparsely sampled data, despite the overall image quality is reasonable for fast and low-dose NDT.

  6. Virtual Sensors: Using Data Mining Techniques to Efficiently Estimate Remote Sensing Spectra

    NASA Technical Reports Server (NTRS)

    Srivastava, Ashok N.; Oza, Nikunj; Stroeve, Julienne

    2004-01-01

    Various instruments are used to create images of the Earth and other objects in the universe in a diverse set of wavelength bands with the aim of understanding natural phenomena. These instruments are sometimes built in a phased approach, with some measurement capabilities being added in later phases. In other cases, there may not be a planned increase in measurement capability, but technology may mature to the point that it offers new measurement capabilities that were not available before. In still other cases, detailed spectral measurements may be too costly to perform on a large sample. Thus, lower resolution instruments with lower associated cost may be used to take the majority of measurements. Higher resolution instruments, with a higher associated cost may be used to take only a small fraction of the measurements in a given area. Many applied science questions that are relevant to the remote sensing community need to be addressed by analyzing enormous amounts of data that were generated from instruments with disparate measurement capability. This paper addresses this problem by demonstrating methods to produce high accuracy estimates of spectra with an associated measure of uncertainty from data that is perhaps nonlinearly correlated with the spectra. In particular, we demonstrate multi-layer perceptrons (MLPs), Support Vector Machines (SVMs) with Radial Basis Function (RBF) kernels, and SVMs with Mixture Density Mercer Kernels (MDMK). We call this type of an estimator a Virtual Sensor because it predicts, with a measure of uncertainty, unmeasured spectral phenomena.

  7. Coadding Techniques for Image-based Wavefront Sensing for Segmented-mirror Telescopes

    NASA Technical Reports Server (NTRS)

    Smith, Scott; Aronstein, David; Dean, Bruce; Acton, Scott

    2007-01-01

    Image-based wavefront sensing algorithms are being used to characterize optical performance for a variety of current and planned astronomical telescopes. Phase retrieval recovers the optical wavefront that correlates to a series of diversity-defocused point-spread functions (PSFs), where multiple frames can be acquired at each defocus setting. Multiple frames of data can be coadded in different ways; two extremes are in "image-plane space," to average the frames for each defocused PSF and use phase retrieval once on the averaged images, or in "pupil-plane space," to use phase retrieval on every set of PSFs individually and average the resulting wavefronts. The choice of coadd methodology is particularly noteworthy for segmented-mirror telescopes that are subject to noise that causes uncorrelated motions between groups of segments. Using data collected on and simulations of the James Webb Space Telescope Testbed Telescope (TBT) commissioned at Ball Aerospace, we show how different sources of noise (uncorrelated segment jitter, turbulence, and common-mode noise) and different parts of the optical wavefront, segment and global aberrations, contribute to choosing the coadd method. Of particular interest, segment piston is more accurately recovered in "image-plane space" coadding, while segment tip/tilt is recovered in "pupil-plane space" coadding.

  8. Co-adding techniques for image-based wavefront sensing for segmented-mirror telescopes

    NASA Astrophysics Data System (ADS)

    Smith, J. S.; Aronstein, David L.; Dean, Bruce H.; Acton, D. S.

    2007-09-01

    Image-based wavefront sensing algorithms are being used to characterize the optical performance for a variety of current and planned astronomical telescopes. Phase retrieval recovers the optical wavefront that correlates to a series of diversity-defocused point-spread functions (PSFs), where multiple frames can be acquired at each defocus setting. Multiple frames of data can be co-added in different ways; two extremes are in "image-plane space," to average the frames for each defocused PSF and use phase retrieval once on the averaged images, or in "pupil-plane space," to use phase retrieval on each PSF frame individually and average the resulting wavefronts. The choice of co-add methodology is particularly noteworthy for segmented-mirror telescopes that are subject to noise that causes uncorrelated motions between groups of segments. Using models and data from the James Webb Space Telescope (JWST) Testbed Telescope (TBT), we show how different sources of noise (uncorrelated segment jitter, turbulence, and common-mode noise) and different parts of the optical wavefront, segment and global aberrations, contribute to choosing the co-add method. Of particular interest, segment piston is more accurately recovered in "image-plane space" co-adding, while segment tip/tilt is recovered in "pupil-plane space" co-adding.

  9. Fast and low-dose computed laminography using compressive sensing based technique

    NASA Astrophysics Data System (ADS)

    Abbas, Sajid; Park, Miran; Cho, Seungryong

    2015-03-01

    Computed laminography (CL) is well known for inspecting microstructures in the materials, weldments and soldering defects in high density packed components or multilayer printed circuit boards. The overload problem on x-ray tube and gross failure of the radio-sensitive electronics devices during a scan are among important issues in CL which needs to be addressed. The sparse-view CL can be one of the viable option to overcome such issues. In this work a numerical aluminum welding phantom was simulated to collect sparsely sampled projection data at only 40 views using a conventional CL scanning scheme i.e. oblique scan. A compressive-sensing inspired total-variation (TV) minimization algorithm was utilized to reconstruct the images. It is found that the images reconstructed using sparse view data are visually comparable with the images reconstructed using full scan data set i.e. at 360 views on regular interval. We have quantitatively confirmed that tiny structures such as copper and tungsten slags, and copper flakes in the reconstructed images from sparsely sampled data are comparable with the corresponding structure present in the fully sampled data case. A blurring effect can be seen near the edges of few pores at the bottom of the reconstructed images from sparsely sampled data, despite the overall image quality is reasonable for fast and low-dose NDT.

  10. Prediction of a future washover landscape based on airborne remote sensing techniques

    SciTech Connect

    Eleveld, M.A.

    1997-06-01

    International recognition and protection of the Wadden Sea area was established after the {open_quote}Ramsar Convention on Wetlands of International Importance, Especially as Waterfowl Habitat{close_quote}. The Dutch government policy of dynamic preservation of the Dutch coast gives nature almost a free reign at locations designated as natural areas, e.g. the extremes of the Dutch Wadden islands. Management is involved in monitoring the coastal development with the purpose of gaining more insight in the processes affecting these areas, subsequently allowing prediction. An important process observed on the eastern ends of the Wadden islands is the occurrence of washovers. This geomorphological phenomenon, resulting in sand transport from the foredunes to the saltmarsh and tidal flats, has a major ecological impact, influencing among other things the species composition of the saltmarsh. To monitor the washovers several airborne sensors were used. Information on the formation and stabilization of washovers by vegetation, was extracted from multitemporal airborne videography and scanned aerial photographs. Based on the trends derived from these sequential images, digital elevation data and morphological parameters derived from laser altimetry, dynamic modelling in a GIS environment was applied, which resulted in the prediction of the place of washovers and the amount sediment that could be deposited on saltmarsh in the coming years. The general conclusion is that, the presence of washovers causes environmental heterogeneity resulting in a high species diversity. Multitemporal airborne remote sensing data are not only useful for monitoring the landscape but the data also support spatio-temporal modelling.

  11. Modelling submerged coastal environments: Remote sensing technologies, techniques, and comparative analysis

    NASA Astrophysics Data System (ADS)

    Dillon, Chris

    Built upon remote sensing and GIS littoral zone characterization methodologies of the past decade, a series of loosely coupled models aimed to test, compare and synthesize multi-beam SONAR (MBES), Airborne LiDAR Bathymetry (ALB), and satellite based optical data sets in the Gulf of St. Lawrence, Canada, eco-region. Bathymetry and relative intensity metrics for the MBES and ALB data sets were run through a quantitative and qualitative comparison, which included outputs from the Benthic Terrain Modeller (BTM) tool. Substrate classification based on relative intensities of respective data sets and textural indices generated using grey level co-occurrence matrices (GLCM) were investigated. A spatial modelling framework built in ArcGIS(TM) for the derivation of bathymetric data sets from optical satellite imagery was also tested for proof of concept and validation. Where possible, efficiencies and semi-automation for repeatable testing was achieved using ArcGIS(TM) ModelBuilder. The findings from this study could assist future decision makers in the field of coastal management and hydrographic studies. Keywords: Seafloor terrain characterization, Benthic Terrain Modeller (BTM), Multi-beam SONAR, Airborne LiDAR Bathymetry, Satellite Derived Bathymetry, ArcGISTM ModelBuilder, Textural analysis, Substrate classification.

  12. Comparison of Aerial and Terrestrial Remote Sensing Techniques for Quantifying Forest Canopy Structural Complexity and Estimating Net Primary Productivity

    NASA Astrophysics Data System (ADS)

    Fahey, R. T.; Tallant, J.; Gough, C. M.; Hardiman, B. S.; Atkins, J.; Scheuermann, C. M.

    2016-12-01

    Canopy structure can be an important driver of forest ecosystem functioning - affecting factors such as radiative transfer and light use efficiency, and consequently net primary production (NPP). Both above- (aerial) and below-canopy (terrestrial) remote sensing techniques are used to assess canopy structure and each has advantages and disadvantages. Aerial techniques can cover large geographical areas and provide detailed information on canopy surface and canopy height, but are generally unable to quantitatively assess interior canopy structure. Terrestrial methods provide high resolution information on interior canopy structure and can be cost-effectively repeated, but are limited to very small footprints. Although these methods are often utilized to derive similar metrics (e.g., rugosity, LAI) and to address equivalent ecological questions and relationships (e.g., link between LAI and productivity), rarely are inter-comparisons made between techniques. Our objective is to compare methods for deriving canopy structural complexity (CSC) metrics and to assess the capacity of commonly available aerial remote sensing products (and combinations) to match terrestrially-sensed data. We also assess the potential to combine CSC metrics with image-based analysis to predict plot-based NPP measurements in forests of different ages and different levels of complexity. We use combinations of data from drone-based imagery (RGB, NIR, Red Edge), aerial LiDAR (commonly available medium-density leaf-off), terrestrial scanning LiDAR, portable canopy LiDAR, and a permanent plot network - all collected at the University of Michigan Biological Station. Our results will highlight the potential for deriving functionally meaningful CSC metrics from aerial imagery, LiDAR, and combinations of data sources. We will also present results of modeling focused on predicting plot-level NPP from combinations of image-based vegetation indices (e.g., NDVI, EVI) with LiDAR- or image-derived metrics of

  13. Evaluation of remote sensing and automatic data techniques for characterization of wetlands. [Atchafalaya River Basin, Louisiana

    NASA Technical Reports Server (NTRS)

    Cartmill, R. H.

    1974-01-01

    This investigation has been conducted in the Atchafalaya River Basin of South Central Louisiana. This is a humid area of heavily forested swamps with a large volume of flow mostly from a diversion of the lower Mississippi River. Techniques to obtain enlarged imagery from computer compatible tapes of ERTS data without photographic enlargement is explained and illustrated. Techniques of extraction of environmental information from single bands and multiband pattern recognition procedures are explained and evaluated. A comparison of pattern recognition classifications of the Atchafalaya Basin by aircraft multispectral scanner and ERTS MSS data is made. Data for this comparison were gathered within three weeks of each other in the winter of 1973. Scorecards of the accuracy of the classifications are presented. Recommendations are made concerning the utilization of each sensor platform to perform specific tasks of wetlands characterization.

  14. Optical sensing of peroxide using ceria nanoparticles via fluorescence quenching technique

    NASA Astrophysics Data System (ADS)

    Shehata, N.; Samir, E.; Gaballah, S.

    2016-04-01

    This study introduces the application of small ceria nanoparticles (NPs) as optical sensor for peroxide using fluorescence quenching technique. Our synthesized ceria nanoparticles have the ability to adsorb peroxides via its oxygen vacancies. Ceria nanoparticles (NPs) solution with added variable concentrations of hydrogen peroxides is exposed through near UV excitation and the detected visible fluorescent emission is found to be at 520nm, with reduced peak intensity peaks with increasing the peroxide concentrations due to static fluorescence quenching technique. The relative intensity change of the visible fluorescent emission has been reduced to more than 50% at added peroxide concentrations up to 10 wt.%. This research work could be applied further in optical sensors of radicals in biomedical engineering and environmental monitoring.

  15. Remote sensing techniques for mapping range sites and estimating range yield

    NASA Technical Reports Server (NTRS)

    Benson, L. A.; Frazee, C. J.; Waltz, F. A.; Reed, C.; Carey, R. L.; Gropper, J. L.

    1974-01-01

    Image interpretation procedures for determining range yield and for extrapolating range information were investigated for an area of the Pine Ridge Indian Reservation in southwestern South Dakota. Soil and vegetative data collected in the field utilizing a grid sampling design and digital film data from color infrared film and black and white films were analyzed statistically using correlation and regression techniques. The pattern recognition techniques used were K-class, mode seeking, and thresholding. The herbage yield equation derived for the detailed test site was used to predict yield for an adjacent similar field. The herbage yield estimate for the adjacent field was 1744 lbs. of dry matter per acre and was favorably compared to the mean yield of 1830 lbs. of dry matter per acre based upon ground observations. Also an inverse relationship was observed between vegetative cover and the ratio of MSS 5 to MSS 7 of ERTS-1 imagery.

  16. Investigations of remote sensing techniques for early detection of Dutch elm disease

    NASA Technical Reports Server (NTRS)

    Hammerschlag, R. S.; Sopstyle, W. J.

    1975-01-01

    Several forms of aerial photography were pursued in quest of a technique which could provide early detection of Dutch elm disease. The two most promising techniques tested were multispectral photography with object enhancement and biband ratioing coupled with scanning microdensitometry. For practical purposes the multispectral system has the advantage of providing a readily interpretable image in a relatively short time. Laboratory studies indicated that less emphasis should be placed on the use of a red filter or the near infrared beyond 750 mm for early detection of stress within a single plant species. Color infrared film would be optimal when used for a long term detection of loss of plant vigor which results in a physical change in a plant canopy, but should find minimal practicality for early detection of specific sources of plant stress such as Dutch elm disease. Considerable discretion should be used when interpreting imagery on copy film because of loss of resolution and color definition.

  17. Vibration monitoring of a helicopter blade model using the optical fiber distributed strain sensing technique.

    PubMed

    Wada, Daichi; Igawa, Hirotaka; Kasai, Tokio

    2016-09-01

    We demonstrate a dynamic distributed monitoring technique using a long-length fiber Bragg grating (FBG) interrogated by optical frequency domain reflectometry (OFDR) that measures strain at a speed of 150 Hz, spatial resolution of 1 mm, and measurement range of 20 m. A 5 m FBG is bonded to a 5.5 m helicopter blade model, and vibration is applied by the step relaxation method. The time domain responses of the strain distributions are measured, and the blade deflections are calculated based on the strain distributions. Frequency response functions are obtained using the time domain responses of the calculated deflection induced by the preload release, and the modal parameters are retrieved. Experimental results demonstrated the dynamic monitoring performances and the applicability to the modal analysis of the OFDR-FBG technique.

  18. A regression technique for evaluation and quantification for water quality parameters from remote sensing data

    NASA Technical Reports Server (NTRS)

    Whitlock, C. H.; Kuo, C. Y.

    1979-01-01

    The paper attempts to define optical physics and/or environmental conditions under which the linear multiple-regression should be applicable. It is reported that investigation of the signal response shows that the exact solution for a number of optical physics conditions is of the same form as a linearized multiple-regression equation, even if nonlinear contributions from surface reflections, atmospheric constituents, or other water pollutants are included. Limitations on achieving this type of solution are defined. Laboratory data are used to demonstrate that the technique is applicable to water mixtures which contain constituents with both linear and nonlinear radiance gradients. Finally, it is concluded that instrument noise, ground-truth placement, and time lapse between remote sensor overpass and water sample operations are serious barriers to successful use of the technique.

  19. A preliminary study of air-pollution measurement by active remote-sensing techniques

    NASA Technical Reports Server (NTRS)

    Wright, M. L.; Proctor, E. K.; Gasiorek, L. S.; Liston, E. M.

    1975-01-01

    Air pollutants are identified, and the needs for their measurement from satellites and aircraft are discussed. An assessment is made of the properties of these pollutants and of the normal atmosphere, including interactions with light of various wavelengths and the resulting effects on transmission and scattering of optical signals. The possible methods for active remote measurement are described; the relative performance capabilities of double-ended and single-ended systems are compared qualitatively; and the capabilities of the several single-ended or backscattering techniques are compared quantitatively. The differential-absorption lidar (DIAL) technique is shown to be superior to the other backscattering techniques. The lidar system parameters and their relationships to the environmental factors and the properties of pollutants are examined in detail. A computer program that models both the atmosphere (including pollutants) and the lidar system is described. The performance capabilities of present and future lidar components are assessed, and projections are made of prospective measurement capabilities for future lidar systems. Following a discussion of some important operational factors that affect both the design and measurement capabilities of airborne and satellite-based lidar systems, the extensive analytical results obtained through more than 1000 individual cases analyzed with the aid of the computer program are summarized and discussed. The conclusions are presented. Recommendations are also made for additional studies to investigate cases that could not be explored adequately during this study.

  20. Expanding applications for surface-contaminant sensing using the laser interrogation of surface agents (LISA) technique

    NASA Astrophysics Data System (ADS)

    Ponsardin, Patrick L.; Higdon, N. S.; Chyba, Thomas H.; Armstrong, Wayne T.; Sedlacek, Arthur J., III; Christesen, Steven D.; Wong, Anna

    2004-02-01

    Laser Interrogation of Surface Agents (LISA) is a UV-Raman technique that provides short-range standoff detection and identification of surface-deposited chemical agents. ITT Industries, Advanced Engineering and Sciences Division, is currently developing and expanding the LISA technology under several programs that span a variety of missions for homeland defense. We will present and discuss some of these applications, while putting in perspective the overall evolution undergone by the technique within the last years. These applications include LISA-Recon (now called the Joint Contaminated Surface Detector--JCSD) which was developed under a cost-sharing arrangement with the U.S. Army Soldier and Biological Chemical Command (SBCCOM) for incorporation on the Army"s future reconnaissance vehicles, and designed to demonstrate single-shot on-the-move measurements of chemical contaminants at concentration levels below the Army's requirements. In parallel, LISA-Shipboard is being developed to optimize the sensor technique for detection of surface contaminants in the operational environment of a ship. The most recently started activity is LISA-Inspector that is being developed to provide a transportable sensor in a 'cart-like' configuration.

  1. Stokes-Mueller matrix polarimetry technique for circular dichroism/birefringence sensing with scattering effects.

    PubMed

    Phan, Quoc-Hung; Lo, Yu-Lung

    2017-04-01

    A surface plasmon resonance (SPR)-enhanced method is proposed for measuring the circular dichroism (CD), circular birefringence (CB), and degree of polarization (DOP) of turbid media using a Stokes–Mueller matrix polarimetry technique. The validity of the analytical model is confirmed by means of numerical simulations. The simulation results show that the proposed detection method enables the CD and CB properties to be measured with a resolution of 10 ? 4 refractive index unit (RIU) and 10 ? 5 ?? RIU , respectively, for refractive indices in the range of 1.3 to 1.4. The practical feasibility of the proposed method is demonstrated by detecting the CB/CD/DOP properties of glucose–chlorophyllin compound samples containing polystyrene microspheres. It is shown that the extracted CB value decreases linearly with the glucose concentration, while the extracted CD value increases linearly with the chlorophyllin concentration. However, the DOP is insensitive to both the glucose concentration and the chlorophyllin concentration. Consequently, the potential of the proposed SPR-enhanced Stokes–Mueller matrix polarimetry method for high-resolution CB/CD/DOP detection is confirmed. Notably, in contrast to conventional SPR techniques designed to detect relative refractive index changes, the SPR technique proposed in the present study allows absolute measurements of the optical properties (CB/CD/DOP) to be obtained.

  2. Stokes-Mueller matrix polarimetry technique for circular dichroism/birefringence sensing with scattering effects

    NASA Astrophysics Data System (ADS)

    Phan, Quoc-Hung; Lo, Yu-Lung

    2017-04-01

    A surface plasmon resonance (SPR)-enhanced method is proposed for measuring the circular dichroism (CD), circular birefringence (CB), and degree of polarization (DOP) of turbid media using a Stokes-Mueller matrix polarimetry technique. The validity of the analytical model is confirmed by means of numerical simulations. The simulation results show that the proposed detection method enables the CD and CB properties to be measured with a resolution of 10-4 refractive index unit (RIU) and 10-5 RIU, respectively, for refractive indices in the range of 1.3 to 1.4. The practical feasibility of the proposed method is demonstrated by detecting the CB/CD/DOP properties of glucose-chlorophyllin compound samples containing polystyrene microspheres. It is shown that the extracted CB value decreases linearly with the glucose concentration, while the extracted CD value increases linearly with the chlorophyllin concentration. However, the DOP is insensitive to both the glucose concentration and the chlorophyllin concentration. Consequently, the potential of the proposed SPR-enhanced Stokes-Mueller matrix polarimetry method for high-resolution CB/CD/DOP detection is confirmed. Notably, in contrast to conventional SPR techniques designed to detect relative refractive index changes, the SPR technique proposed in the present study allows absolute measurements of the optical properties (CB/CD/DOP) to be obtained.

  3. Techniques of the environmental observer: India's earth remote sensing program in the age of global information

    NASA Astrophysics Data System (ADS)

    Denicola, Lane A.

    This research examines the emergence in India of earth remote sensing (ERS), a principal medium for environmental analysis, communication, and policy-making. ERS---the science and "craft" of analyzing images of terrestrial phenomena collected by aircraft or satellite---constitutes an information technology whose predominance in environmental discourse has grown continuously since first proposed for such applications by American researchers in 1962. Raising many thorny issues in information access and control, the use and popularization of ERS has intensified dramatically since the mid-1980s. In Westernized discourse (both popular and expert), space research and industry are often depicted at a double-remove from the so-called "developing world," where exotic technologies and esoteric goals are overshadowed by patent human needs and a lack of basic infrastructure. Yet advocates hail the utility of ERS in socially relevant applications, and India has amassed upwards of five decades of experience in space, with systems and products rivaled today only by those of the United States and China. A multi-sited ethnography of a nascent visual medium, the dissertation triangulates on its topic by tracing three analytical threads: (1) a diachronic analysis of Indian ERS satellites as an allegory of statehood and participation in the global present, (2) a synchronic analysis of ERS imagery as a discursive artifact and global information commodity, and (3) an analysis of interpretive practice as observed through a single class of Indian and foreign students at the Indian Institute of Remote Sensing (IIRS), considered here as an "interpretive community" of environmental experts. The dissertation is the result of four years of research with ERS students, faculty, researchers, users and administrators in the U.S., the U.K., Turkey and India. In particular, I conducted nine months of ethnographic fieldwork in India in 2002 and 2005, the latter half of which was spent in participant

  4. Extraction of shoreline changes in Selangor coastal area using GIS and remote sensing techniques

    NASA Astrophysics Data System (ADS)

    Selamat, S. N.; Maulud, K. N. Abdul; Jaafar, O.; Ahmad, H.

    2017-05-01

    Nowadays, coastal zones are facing shoreline changes that stemming from natural and anthropogenic effect. The process of erosion and accretion will affect the physical environment of the shoreline. Therefore, the study of shoreline changes is important to identify the patterns of changes over time. The rapid growth of technology nowadays has facilitated the study of shoreline changes. Geographical Information System (GIS) alongside Remote Sensing (RS) technology is a useful tool to study these changes due to its ability to generate information, monitoring, analysis and prediction of the shoreline changes. Hence, the future projection of the trend for a specific coastal area can be done effectively. This study investigates the impact of shoreline changes to the community in Selangor area which mainly focus on the physical aspects. This study presents preliminary result using satellite image from SPOT 5 to identify the shoreline changes from the year 1984 to 2013 at Selangor coastal area. Extraction of shoreline from satellite image is vital to analyze the erosion and accretion along the shoreline area. This study shows that a shoreline change for the whole area is a categorized as a medium case. The total eroded and accretion of Selangor area from 1984 to 2013 is 2558 hectares and 2583 hectares respectively. As a result, Kapar, Jugra, Telok Panglima Garang and Kelanang are categorized as high risk erosion area. Shoreline changes analysis provides essential information to determine on the shoreline changes trends. Therefore, the results of this study can be used as essential information for conservation and preservation of coastal zone management.

  5. Application of multispectral remote sensing techniques for dismissed mine sites monitoring and rehabilitation

    NASA Astrophysics Data System (ADS)

    Bonifazi, Giuseppe; Serranti, Silvia

    2007-09-01

    Mining activities, expecially those operated in open air (open pit), present a deep impact on the sourrondings. Such an impact, and the related problems, are directly related to the correct operation of the activities, and usually strongly interact with the environment. Impact can be mainly related to the following issues: high volumes of handled material, ii) generation of dust, noise and vibrations, water pollution, visual impact and, finally, mining area recovery at the end of exploitation activities. All these aspects can be considered very important, and must be properly evaluated and monitored. Environmental impact control is usually carried out during and after the end of the mining activities, adopting methods related to the detection, collection, analysis of specific environmental indicators and with their further comparison with reference thresholding values stated by official regulations. Aim of the study was to investigate, and critically evaluate, the problems related to development of an integrated set of procedures based on the collection and the analysis of remote sensed data in order to evaluate the effect of rehabilitation of land contaminated by extractive industry activities. Starting from the results of these analyses, a monitoring and registration of the environmental impact of such operations was performed by the application and the integration of modern information technologies, as the previous mentioned Earth Observation (EO), with Geographic Information Systems (GIS). The study was developed with reference to different dismissed mine sites in India, Thailand and China. The results of the study have been utilized as input for the construction of a knowledge based decision support system finalized to help in the identification of the appropriate rehabilitation technologies for all those dismissed area previously interested by extractive industry activities. The work was financially supported within the framework of the Project ASIA IT&C - CN

  6. The microbial habitability of weathered volcanic glass inferred from continuous sensing techniques.

    PubMed

    Bagshaw, Elizabeth A; Cockell, Charles S; Magan, Naresh; Wadham, Jemma L; Venugopalan, T; Sun, Tong; Mowlem, Matt; Croxford, Anthony J

    2011-09-01

    Basaltic glasses (hyaloclastite) are a widespread habitat for life in volcanic environments, yet their interior physical conditions are poorly characterized. We investigated the characteristics of exposed weathered basaltic glass from a surface outcrop in Iceland, using microprobes capable of continuous sensing, to determine whether the physical conditions in the rock interior are hospitable to microbial life. The material provided thermal protection from freeze-thaw and rapid temperature fluctuations, similar to data reported for other rock types. Water activity experiments showed that at moisture contents less than 13% wet weight, the glass and its weathering product, palagonite, had a water activity below levels suitable for bacterial growth. In pore spaces, however, these higher moisture conditions might be maintained for many days after a precipitation event. Gas exchange between the rock interior and exterior was rapid (< 10 min) when the rocks were dry, but when saturated with water, equilibration took many hours. During this period, we demonstrated the potential for low oxygen conditions within the rock caused by respiratory stimulation of the heterotrophic community within. These conditions might exist within subglacial environments during the formation of the rocks or in micro-environments in the interior of exposed rocks. The experiments showed that microbial communities at the site studied here could potentially be active for 39% of the year, if the depth of the community within the outcrop maintains a balance between access to liquid water and adequate protection from freezing. In the absence of precipitation, the interior of weathered basaltic glass is an extreme and life-limiting environment for microorganisms on Earth and other planets.

  7. Proximal Sensing of Plant-Pathogen Interactions in Spring Barley with Three Fluorescence Techniques

    PubMed Central

    Leufen, Georg; Noga, Georg; Hunsche, Mauricio

    2014-01-01

    In the last years fluorescence spectroscopy has come to be viewed as an essential approach in key research fields of applied plant sciences. However, the quantity and particularly the quality of information produced by different equipment might vary considerably. In this study we investigate the potential of three optical devices for the proximal sensing of plant-pathogen interactions in four genotypes of spring barley. For this purpose, the fluorescence lifetime, the image-resolved multispectral fluorescence and selected indices of a portable multiparametric fluorescence device were recorded at 3, 6, and 9 days after inoculation (dai) from healthy leaves as well as from leaves inoculated with powdery mildew (Blumeria graminis) or leaf rust (Puccinia hordei). Genotype-specific responses to pathogen infections were revealed already at 3 dai by higher fluorescence mean lifetimes in the spectral range from 410 to 560 nm in the less susceptible varieties. Noticeable pathogen-induced modifications were also revealed by the ‘Blue-to-Far-Red Fluorescence Ratio’ and the ‘Simple Fluorescence Ratio’. Particularly in the susceptible varieties the differences became more evident in the time-course of the experiment i.e., following the pathogen development. The relevance of the blue and green fluorescence to exploit the plant-pathogen interaction was demonstrated by the multispectral fluorescence imaging system. As shown, mildewed leaves were characterized by exceptionally high blue fluorescence, contrasting the values observed in rust inoculated leaves. Further, we confirm that the intensity of green fluorescence depends on the pathogen infection and the stage of disease development; this information might allow a differentiation of both diseases. Moreover, our results demonstrate that the detection area might influence the quality of the information, although it had a minor impact only in the current study. Finally, we highlight the relevance of different excitation

  8. Micro - Watershed Development Plans Using Remote Sensing & GIS Techniques Panoli Village, Ahmednagar, Maharashtra, Iindia

    NASA Astrophysics Data System (ADS)

    Purushothuman, S.

    2013-05-01

    Sustainable development aims at maintaining the equilibrium between the human needs and economic developments within the parameters of environmental conservation through efficient use of natural resources to ensure tradeoff between desired productions - consumption levels. The well-known Brundtland Commission defined sustainability as a "development that meets the needs of the present without compromising the ability of future generations to meet their own needs. In essence, the sustainable development is a process of change in which the exploitation of resources, the direction of investments, the orientation of technological development and instrumental changes, all are in harmony". The sustainable development of natural resources is based on maintaining the fragile ecosystem balance between the productivity functions and conservation practices through monitoring and identification of problem areas, agricultural practices, crop rotation, use of bio-fertilizers, energy efficient farming methods and reclamation of underutilized lands. Sustainable development requires a holistic approach towards natural resources after taking into account the precarious environmental conditions. Watershed development has become the main involvement in natural resource management in India. This Dissertation demonstrates the use of Remote Sensing and GIS-based modeling framework for local-level planning, incorporating the sustainability aspects of Micro-watershed development. A case study has been taken in Panoli Village, Parner Taluka, Ahmanagar District, Maharashtra state to demonstrate the implementation of these new technologies for watershed prioritization and sustainable development. Watershed development and its management is achieved through the combination of database within the watershed boundaries of a drainage area to optimally develop land, water and plant resources to meet the basic minimum needs of the people in a sustained manner.;

  9. Hyperspectral Remote Sensing Techniques in Predicting Phycocyanin Concentrations in Cyanobacteria: A Comprehensive Study

    NASA Astrophysics Data System (ADS)

    Mishra, S.; Mishra, D. R.; Schluchter, W. M.

    2009-12-01

    The purpose of this research was to evaluate the performance of existing spectral band ratio algorithms and develop a novel algorithm to quantify phycocyanin (PC) in cyanobacteria using hyperspectral remotely-sensed data. We performed four spectroscopic experiments on two different laboratory cultured cyanobacterial species and found that the existing band ratio algorithms are highly sensitive to chlorophylls, making them inaccurate in predicting cyanobacterial abundance in the presence of other chlorophyll-containing organisms. Our results also show that the widely used 654 nm reflectance peak in existing algorithms is highly sensitive to changes in chlorophyll-a concentration and offers poor PC predictive ability. We present a novel spectral band ratio algorithm that is least sensitive to the presence of chlorophyll. The newly developed band ratio model showed promising results by yielding low root mean squared error (RMSE, 15,260 cells mL-1) and significantly low relative root mean squared error (RMS, 101%) as compared to the existing band ratio algorithms. Natural logarithmic transformation of the new model yielded the lowest RMSE (13,885 cells mL-1) and a high coefficient of determination (0.95) between measured and predicted PC concentration. We also show that the new algorithm is species independent and accurately retrieves PC concentration in the presence of varying amount of chlorophyll-a in the system. Band setting of the model confirms that it can be used for retrieval of PC using hyperspectral sensors such as Hyperion as well as data acquired by other airborne sensors. Figure (A, B, C) Percent reflectance spectra of Synechocystis PCC 6803 from Exp I, II, III respectively. (D) Percent reflectance spectra of Anabaena from Exp IV. Data collected from these experiments were included in the evaluation of existing PC predictive models and the calibration and validation of the new spectral band ratio model.

  10. Assessment of practicality of remote sensing techniques for a study of the effects of strip mining in Alabama

    NASA Technical Reports Server (NTRS)

    Hughes, T. H.; Dillion, A. C., III; White, J. R., Jr.; Drummond, S. E., Jr.; Hooks, W. G.

    1975-01-01

    Because of the volume of coal produced by strip mining, the proximity of mining operations, and the diversity of mining methods (e.g. contour stripping, area stripping, multiple seam stripping, and augering, as well as underground mining), the Warrior Coal Basin seemed best suited for initial studies on the physical impact of strip mining in Alabama. Two test sites, (Cordova and Searles) representative of the various strip mining techniques and environmental problems, were chosen for intensive studies of the correlation between remote sensing and ground truth data. Efforts were eventually concentrated in the Searles Area, since it is more accessible and offers a better opportunity for study of erosional and depositional processes than the Cordova Area.

  11. Mining remote sensing image data: an integration of fuzzy set theory and image understanding techniques for environmental change detection

    NASA Astrophysics Data System (ADS)

    Eklund, Peter W.; You, Jane; Deer, Peter

    2000-04-01

    This paper presents an image understanding approach to mine remotely sensed image data from different source dates for environmental change detection. It is focused on the immediate needs for knowledge discovery from large sets of image data for environmental monitoring. In contrast to the traditional approaches for change detection, we introduce a wavelet-based hierarchical scheme which integrates fuzzy set theory and image understanding techniques for knowledge discovery of the remote image data. The proposed approach includes algorithms for hierarchical change detection, region representations and classification. The effectiveness of the proposed algorithms is demonstrated throughout the completion of three tasks, namely hierarchial detection of change by fuzzy post classification comparisons, localization of change by B-spline based region representation, and categorization of change by hierarchial texture classification.

  12. Research on giant magnetostrictive actuator online nonlinear modeling based on data driven principle with grating sensing technique

    NASA Astrophysics Data System (ADS)

    Han, Ping

    2017-01-01

    A novel Giant Magnetostrictive Actuator (GMA) experimental system with Fiber Bragg Grating (FBG) sensing technique and its modeling method based on data driven principle are proposed. The FBG sensors are adopted to gather the multi-physics fields' status data of GMA considering the strong nonlinearity of the Giant Magnetostrictive Material and GMA micro-actuated structure. The feedback features are obtained from the raw dynamic status data, which are preprocessed by data fill and abnormal value detection algorithms. Correspondingly the Least Squares Support Vector Machine method is utilized to realize GMA online nonlinear modeling with data driven principle. The model performance and its relative algorithms are experimentally evaluated. The model can regularly run in the frequency range from 10 to 1000 Hz and temperature range from 20 to 100 °C with the minimum prediction error stable in the range from -1.2% to 1.1%.

  13. A streak camera based fiber optic pulsed polarimetry technique for magnetic sensing to sub-mm resolution.

    PubMed

    Smith, R J; Weber, T E

    2016-11-01

    The technique of fiber optic pulsed polarimetry, which provides a distributed (local) measurement of the magnetic field along an optical fiber, has been improved to the point where, for the first time, photocathode based optical detection of backscatter is possible with sub-mm spatial resolutions. This has been realized through the writing of an array of deterministic fiber Bragg gratings along the fiber, a so-called backscatter-tailored optical fiber, producing a 34 000-fold increase in backscatter levels over Rayleigh. With such high backscatter levels, high repetition rate lasers are now sufficiently bright to allow near continuous field sensing in both space and time with field resolutions as low as 0.005 T and as high as 170 T over a ∼mm interval given available fiber materials.

  14. E-tracers: A New Technique for Wireless Sensing Under Ice Sheets

    NASA Astrophysics Data System (ADS)

    Burrow, S.; Wadham, J. L.; Salter, M.; Barnes, R.

    2009-12-01

    A significant hurdle to the understanding of ice sheet basal hydrology and its coupling with ice motion is the difficulty in making in-situ measurements along a flow path. While dye tracing techniques may be used in small glaciers to determine transit times of surface melt water through the sub-glacial system, they provide no information on in situ conditions (e.g. pressure) and are ineffective at ice-sheet scale where dilution is high. The use of tethered sensor packages is complicated by the long lengths (~100’s m) and torturous path of the moulins and conduits within ice sheets. Recent attempts to pass solid objects (rubber ducks) and other sensor packages through glacial moulins have confirmed the difficultly in deploying sensors into the sub glacial environment. Here, we report the first successful deployment and recovery of compact, electronic units to moulins up to 7 km from the margin of a large land-terminating Greenland outlet. The technique uses RF (Radio Frequency) location to create an electronic tracer (an ‘e-tracer’) enabling a data-logging sensor package to be located in the pro-glacial flood plain once it has passed through the ice sheet. A number of individual packages are used in each deployment mitigating for the risk that some may become stuck within the moulin or lodge in an inaccessible part of the floodplain. In preliminary tests on the Leverett glacier in West Greenland during August 2009 we have demonstrated that this technique can be used to locate and retrieve dummy sensor packages: 50% and 20% of the dummy sensor packages introduced to moulins at 1 and 7 km from the ice sheet terminus respectively, emerged in the sub-glacial stream. It was possible to effectively detect the e-tracer units (which broadcast on 151MHz with 10mW of power) over a horizontal range of up to 5km across the pro-glacial floodplain and locate them to a high accuracy, allowing visual recognition and manual recovery. These performance statistics give this

  15. Remote Sensing Techniques as a Tool for Geothermal Exploration: the Case Study of Blawan Ijen, East Java

    NASA Astrophysics Data System (ADS)

    Pasqua, Claudio; Verdoya, Massimo

    2014-05-01

    The use of remote sensing techniques in the initial phase of geothermal surveys represents a very cost-effective tool, which can contribute to a successful exploration program. Remote sensing allows the analysis of large surfaces and can lead to a significant improvement of the identification of surface thermal anomalies, through the use of thermal infra red data (TIR), as well as of zones of widespread and recent faulting, which can reflect larger permeability of geological formations. Generally, the fractures analysis from remote sensing can be fundamental to clarify the structural setting of an area. In a regional volcanic framework, it can also help in defining the spatial and time evolution of the different volcanic apparatuses. This paper describes the main results of a remote sensing study, conducted in the Blawan-Ijen volcanic area (East Java), which is at present subject of geothermal exploration. This area is characterized by the presence of a 15 km wide caldera originated by a collapsed strato volcano. This event was followed by the emplacement of several peri-calderic and intra-calderic volcanoes, among which G. Raung, as testified by the frequent occurrence of shallow earthquakes and by H2S emission and sulfur deposition, and G. Kawah Ijen, occurring at the eastern rim of the caldera, are still active. The summit of G. Kawah Ijen volcano consists of two interlocking craters forming an E-W elongated depression filled up by a hyperacidic lake. Along the southern shore of the lake, a small rhyolitic dome occurs, which exhibits strong fumarolic activity with temperature of as much as 600 °C. We performed an analysis based on the combined interpretation of Landsat ETM+7, Aster and Synthetic Aperture Radar (SAR) images, focused on the identification of subsurface high permeability zones. The main trends of the linear features as derived from the fractures analysis, as well as their relation with the distribution of volcanic centres, were identified

  16. Current research in geological applications of remote sensing techniques and implications for petroleum geology

    SciTech Connect

    Settle, M.; Taranik, J.V.

    1983-03-01

    Exploration geologists have made extensive use of aerial photography and orbital Landsat imagery, primarily for purposes of structural mapping. The Landsat 4 spacecraft launched in July 1982 is carrying a new imaging instrument called the Thematic Mapper which represents a significant advance over earlier Landsat sensors. Experimental studies with airborne Thematic Mapper simulators tentatively indicate that these measurement capabilities will have a major payoff in terms of our ability to detect variations in clay mineralogy and abundance, to map bleaching effects in surficial rocks and soils that may be produced by hydrocarbon seepage, and to detect variations in the distribution and vigor of natural vegetation that are also related to seepage phenomena. The improved spatial resolution of the Thematic Mapper will enable photogeologists to identify smaller scale landforms and drainage features which will also contribute to improved structural mapping capabilities. Research is currently underway to determine the utility of Thematic Mapper measurements for geologic mapping in complex areas characterized by large relief and extensive vegetation. Radar imaging techniques also represent an important source of information concerning geological conditions at the earth's surface. Exploration geologists have made extensive use of airborne radar surveys for terrain analysis and structural mapping, particularly in tropical environments. Orbital radar techniques may provide an important new tool for mapping facies variations within sedimentary basins.

  17. Specificity of noninvasive blood glucose sensing using optical coherence tomography technique: a pilot study

    NASA Astrophysics Data System (ADS)

    Larin, Kirill V.; Motamedi, Massoud; Ashitkov, Taras V.; Esenaliev, Rinat O.

    2003-05-01

    Noninvasive monitoring of blood glucose concentration in diabetic patients would significantly reduce complications and mortality associated with this disease. In this paper, we experimentally and theoretically studied specificity of noninvasive blood glucose monitoring with the optical coherence tomography (OCT) technique. OCT images and signals were obtained from skin of Yucatan micropigs and New Zealand rabbits. Obtained results demonstrate that: (1) several body osmolytes may change the refractive index mismatch between the interstitial fluid (ISF) and scattering centres in tissue, however the effect of the glucose is approximately one to two orders of magnitude higher; (2) an increase of the ISF glucose concentration in the physiological range (3-30 mM) may decrease the scattering coefficient by 0.22% mM-1 due to cell volume change; (3) stability of the OCT signal slope is dependent on tissue heterogeneity and motion artefacts; and (4) moderate skin temperature fluctuations (+/-1 °C) do not decrease accuracy and specificity of the OCT-based glucose sensor, however substantial skin heating or cooling (several °C) significantly change the OCT signal slope. These results suggest that the OCT technique may provide blood glucose concentration monitoring with sufficient specificity under normal physiological conditions.

  18. Comparison of feature reduction techniques for classification of hyperspectral remote sensing data

    NASA Astrophysics Data System (ADS)

    Serpico, Sebastiano B.; D'Inca, Massimo; Melgani, Farid; Moser, Gabriele

    2003-03-01

    The task of the analysis of hyperspectral data, due to their high spectrla reolution, requires dealing with the problem of the curse of dimenioality. Many feature selection/extraction techniques have been developed, which map the hyperdimensional feature space in a lower-dimensional space, based on the optimization of a suitable criterion function. This paper studies the impact of several such techniques and of the criterion chosen on the accuracy of different supervised classifiers. The compared methods are the 'Sequential Forward Selection' (SFS), the 'Steepest Ascent' (SA), the 'Fast Constrained Search' (FCS), the 'Projection Pursuit' (PP) and the 'Decision Boundary Feature Extraction' (DBFE), while the considered criterion functions are standard interclass distance measures. SFS is well known for its conceptual and computational simplicity. SA provides more effective subsets of selected features at the price of a higher computational cost. DBFE is an effective transformation technque, usually applied after a preliminary feature-space reduction through PP. The experimental comparison is performed on an AVIRIS hyperspectral data set characterized by 220 spectral bands and nine ground cover classes. The computational time of each algorithm is also reported.

  19. Remote Sensing of Atmospheric and Ionospheric Disturbances using Radio Science Techniques

    NASA Astrophysics Data System (ADS)

    Yang, Y. M.; Paik, M.; Oudrhiri, K.; Buccino, D.; Kahan, D. S.

    2016-12-01

    Atmospheres and ionospheres can have significant impacts on radio frequency signal propagation such as Deep Space Network and Global Navigation Satellite System (GNSS, including Global Position System (GPS)) measurements. Previous studies indicate that Earth's atmospheric, surface, and interior processes, such as seismic activities, tsunamis, meteor impacts, and volcanic eruptions, are able to trigger atmospheric acoustic and gravity waves (AGWs), which potentially induce traveling ionospheric disturbances (TIDs) in the upper atmosphere. These perturbations are relatively small to the background of atmospheric and ionospheric profiles but detectable to radio frequency signals. In this research, we will demonstrate the ability of using ground- and space-based radio science techniques to detect and characterize atmospheric and ionospheric wave propagation from solid earth events including seismic activities and tsunamis. The detected wave trains with wave characteristics such as propagation speeds and wavelengths are classified through analysis of the line of sight (LOS) and radio occultation measurements made by different frequency radio waves. Dominant and different physical characteristics of AGW and TID propagations are found to be associated with specific surface wave propagations. In this research, we compare observations made by different frequency radio signals, corresponding model simulations, and other geophysical measurements of surface wave propagation such as seismometers, infrasound arrays and DART buoys. Results are shown to improve our understanding of the interactions between surface, atmosphere, and ionosphere. The better understanding of the coupling between planetary interior, surface, atmosphere, and ionosphere will benefit from innovative radio science techniques.

  20. Estimating primary productivity of tropical oil palm in Malaysia using remote sensing technique and ancillary data

    NASA Astrophysics Data System (ADS)

    Kanniah, K. D.; Tan, K. P.; Cracknell, A. P.

    2014-10-01

    The amount of carbon sequestration by vegetation can be estimated using vegetation productivity. At present, there is a knowledge gap in oil palm net primary productivity (NPP) at a regional scale. Therefore, in this study NPP of oil palm trees in Peninsular Malaysia was estimated using remote sensing based light use efficiency (LUE) model with inputs from local meteorological data, upscaled leaf area index/fractional photosynthetically active radiation (LAI/fPAR) derived using UK-DMC 2 satellite data and a constant maximum LUE value from the literature. NPP values estimated from the model was then compared and validated with NPP estimated using allometric equations developed by Corley and Tinker (2003), Henson (2003) and Syahrinudin (2005) with diameter at breast height, age and the height of the oil palm trees collected from three estates in Peninsular Malaysia. Results of this study show that oil palm NPP derived using a light use efficiency model increases with respect to the age of oil palm trees, and it stabilises after ten years old. The mean value of oil palm NPP at 118 plots as derived using the LUE model is 968.72 g C m-2 year-1 and this is 188% - 273% higher than the NPP derived from the allometric equations. The estimated oil palm NPP of young oil palm trees is lower compared to mature oil palm trees (<10 years old), as young oil palm trees contribute to lower oil palm LAI and therefore fPAR, which is an important variable in the LUE model. In contrast, it is noted that oil palm NPP decreases with respect to the age of oil palm trees as estimated using the allomeric equations. It was found in this study that LUE models could not capture NPP variation of oil palm trees if LAI/fPAR is used. On the other hand, tree height and DBH are found to be important variables that can capture changes in oil palm NPP as a function of age.

  1. On the detection of adobe buried archaeological structures using multiscale remote sensing techniques : Piramide Naranja in Cahuachi (Peru)

    NASA Astrophysics Data System (ADS)

    Masini, N.; Rizzo, E.; Lasaponara, R.; Orefici, G.

    2009-04-01

    The detection of buried adobe structures is a crucial issue for the remote sensing (ground, aerial and satellite) applied to archaeology for the widespread of sun-dried earth as building material in several ancient civilizations in Central and Southern America, Middle East and North Africa. Moreover it is complex, due to the subtle contrast existing between the archaeological features and the surrounding, especially in arid setting, as in the case of the well know Nazca Ceremonial Centre of Cahuachi, located in the desert of Nazca (Southern Peru) . During the last two decades of excavations adobe monuments dating back from the 6th century B.C. to the 4th century A.D have been highlighted by the Centro de Estudios Arqueológicos Precolombinos (CEAP), an italian-peruvian mission directed by Giuseppe Orefici. Actually, the archaeologists are excavating and restoring the core of the Ceremonial centre where is located a great pyramid (kown as Gran Piramide). Beginning from 2007 the two institutes of CNR, IMAA and IBAM, have been involved by CEAP, in order to provide a scientific and technological support for the archaeological research. Therefore, a multi-scale approach based on the integration of aerial and satellite remote sensing with geophysical techniques was employed in order to provide data useful for archaeological excavations. The abstract refers to the last investigations performed on a mound, known as "Piramide Naranja", during the 2008. The processing of an aerial imagery time series and two QuickBird satellite images acquired in 2002 and 2005, allowed for identifying some features related to shallow and buried structures. Such features were verified by means of geophysical prospections, performed by using the magnetometric method which observed changes in the magnetic field within the first few metres beneath the subsurface detecting buried walls and anomalies linked to ceramic deposits referable to possible tombs. Finally, the integration of all data

  2. Regional glacier changes in the Ötztal Alps (Tyrol, Austria) - Results from different remote sensing techniques

    NASA Astrophysics Data System (ADS)

    Klug, Christoph; Rieg, Lorenzo; Sailer, Rudolf

    2017-04-01

    Climate change will pose a variety of challenges in the future, with global sea level rise among the most important ones. Out of all contributions to sea level rise, the contribution from glaciers is the one with the highest uncertainty. This is mainly because only very few and not necessarily representative glaciers are measured regularly. Among others, this limits the validation of extrapolation models. On a regional scale, remote sensing data offer several possibilities for the mapping and monitoring of glaciers. Especially with the advent of very high resolution data, new possibilities can be exploited. The monitoring of glacier area, the calculation of the geodetic glacier mass balances and the tracking of changes in the seasonal snow and firn bodies of glaciers on a regional scale can not only help to enhance the spatial, but also the temporal coverage of observations. The Ötztal Alps in Tyrol, Austria have been a research focus for the University of Innsbruck for several decades. Ongoing glaciological field measurements at two reference glaciers (Hintereisferner and Kesselwandferner) and data from different remote sensing techniques provide a valuable basis for a variety of research. The presented study analyses high-resolution airborne laser scanning (ALS) data, with more than 10 years of annual campaigns on Hintereisferner (2001-2013) and two campaigns covering all of the Ötztal Alps (2006 and 2010) in combination with orthoimages and optical satellite data. Furthermore Pléiades tri-stereo data (2015 and 2016) are available to calculate very high resolution and high quality digital terrain models (DTM). These DTM can be used to extend the time series in combination with the DTM based on ALS data and enable the calculation of the geodetic glacier mass balance for over 150 glaciers within the study area. Furthermore, the optical information (ALS intensity, orthoimages and optical satellite data) is used for surface classification in order to monitor the

  3. Using passive, thermal remote sensing techniques for detecting subsurface gravel accumulations in vegetated, unconsolidated sedimentary terrains

    NASA Technical Reports Server (NTRS)

    Burns, Gregory S.; Scholen, Douglas E.

    1989-01-01

    Multiband radiometric data from an airborne imaging thermal scanner are being studied for use in finding buried gravel deposits. The techniques are based on measuring relative differences in the thermal properties between gravel-laden targets and the surrounding gravelless background. These properties are determined from modeling the spectral radiant emittance recorded over both types of surfaces in conjunction with ground measurements of the most significant heat flows above and below the surface. Thermodynamic properties of sampled materials from control sites are determined, and diurnal and annual subsurface heat waves are recorded. Thermal models that account for heat exchange at the surface, as well as varying levels of soil moisture, humidity, and vegetation, are needed for adaptation and modification to simulate the physical and radiative environments of this region.

  4. An integrated study of earth resources in the state of California using remote sensing techniques

    NASA Technical Reports Server (NTRS)

    Colwell, R. N. (Principal Investigator)

    1975-01-01

    The author has identified the following significant results. A weighted stratified double sample design using hardcopy LANDSAT-1 and ground data was utilized in developmental studies for snow water content estimation. Study results gave a correlation coefficient of 0.80 between LANDSAT sample units estimates of snow water content and ground subsamples. A basin snow water content estimate allowable error was given as 1.00 percent at the 99 percent confidence level with the same budget level utilized in conventional snow surveys. Several evapotranspiration estimation models were selected for efficient application at each level of data to be sampled. An area estimation procedure for impervious surface types of differing impermeability adjacent to stream channels was developed. This technique employs a double sample of 1:125,000 color infrared hightflight transparency data with ground or large scale photography.

  5. Review of passive-blind detection in digital video forgery based on sensing and imaging techniques

    NASA Astrophysics Data System (ADS)

    Tao, Junjie; Jia, Lili; You, Ying

    2016-01-01

    Advances in digital video compression and IP communication technologies raised new issues and challenges concerning the integrity and authenticity of surveillance videos. It is so important that the system should ensure that once recorded, the video cannot be altered; ensuring the audit trail is intact for evidential purposes. This paper gives an overview of passive techniques of Digital Video Forensics which are based on intrinsic fingerprints inherent in digital surveillance videos. In this paper, we performed a thorough research of literatures relevant to video manipulation detection methods which accomplish blind authentications without referring to any auxiliary information. We presents review of various existing methods in literature, and much more work is needed to be done in this field of video forensics based on video data analysis and observation of the surveillance systems.

  6. Spectrum sensing of trace C(2)H(2) detection in differential optical absorption spectroscopy technique.

    PubMed

    Chen, Xi; Dong, Xiaopeng

    2014-09-10

    An improved algorithm for trace C(2)H(2) detection is presented in this paper. The trace concentration is accurately calculated by focusing on the absorption spectrum from the frequency domain perspective. The advantage of the absorption spectroscopy frequency domain algorithm is its anti-interference capability. First, the influence of the background noise on the minimum detectable concentration is greatly reduced. Second, the time-consuming preprocess of spectra calibration in the differential optical absorption spectroscopy technique is skipped. Experimental results showed the detection limit of 50 ppm is achieved at a lightpath length of 0.2 m. This algorithm can be used in real-time spectrum analysis with high accuracy.

  7. New Dielectric Sensors and Sensing Techniques for Soil and Snow Moisture Measurements

    PubMed Central

    Stacheder, Markus; Koeniger, Franz; Schuhmann, Rainer

    2009-01-01

    Measurements of material moisture are essential in fields such as agriculture or civil engineering. Electromagnetic techniques, more precisely dielectric methods, have gained wide acceptance in the last decades. Frequency or Time Domain methods take advantage of the high dielectric permittivity of water compared to dry materials. This paper presents four new dielectric sensors for the determination of soil or snow water content. After a short introduction into the principles, both the hardware and operating mode of each sensor are described. Field test results show the advantages and potentials such as automatic measurement and profiling, state-of-ground detection or large-scale determination. From the results it follows that the presented sensors offer promising new tools for modern environmental research. PMID:22574056

  8. Remote sensing of OH in the atmosphere using the technique of laser-induced fluorescence

    NASA Technical Reports Server (NTRS)

    Wang, C. C.

    1983-01-01

    The use of a laser-induced fluorescence technique for the sensitive measurement of the atmospheric hydroxyl radical is discussed. Results of laboratory studies of the fluorescence and other spectroscopic properties of OH which allow the calculation of OH concentrations from the returned signals for various altitudes, water vapor contents and temperatures are presented. The experimental setup used for airborne OH measurements is then described, with particular attention given to the use of a telescope for excitation and light collection in a coaxial configuration and the periodic tuning of the exciting radiation necessary to obtain an OH signal in the presence of strong solar and nonresonant fluorescence backgrounds. The best detection limit obtained to date with the system is noted to be about 700,000 OH/cu cm, and it is expected that, with planned improvements in detection and tuning schemes, limits in the neighborhood of 1,000,000 OH/cu cm will be achieved routinely.

  9. Novel fluorescence detection technique for non-contact temperature sensing in microchip PCR.

    PubMed

    Mondal, Sudip; Venkataraman, V

    2007-08-01

    DNA amplification using Polymerase Chain Reaction (PCR) in a small volume is used in Lab-on-a-chip systems involving DNA manipulation. For few microliters of volume of liquid, it becomes difficult to measure and monitor the thermal profile accurately and reproducibly, which is an essential requirement for successful amplification. Conventional temperature sensors are either not biocompatible or too large and hence positioned away from the liquid leading to calibration errors. In this work we present a fluorescence based detection technique that is completely biocompatible and measures directly the liquid temperature. PCR is demonstrated in a 3 muL silicon-glass microfabricated device using non-contact induction heating whose temperature is controlled using fluorescence feedback from SYBR green I dye molecules intercalated within sensor DNA. The performance is compared with temperature feedback using a thermocouple sensor. Melting curve followed by gel electrophoresis is used to confirm product specificity after the PCR cycles.

  10. New dielectric sensors and sensing techniques for soil and snow moisture measurements.

    PubMed

    Stacheder, Markus; Koeniger, Franz; Schuhmann, Rainer

    2009-01-01

    Measurements of material moisture are essential in fields such as agriculture or civil engineering. Electromagnetic techniques, more precisely dielectric methods, have gained wide acceptance in the last decades. Frequency or Time Domain methods take advantage of the high dielectric permittivity of water compared to dry materials. This paper presents four new dielectric sensors for the determination of soil or snow water content. After a short introduction into the principles, both the hardware and operating mode of each sensor are described. Field test results show the advantages and potentials such as automatic measurement and profiling, state-of-ground detection or large-scale determination. From the results it follows that the presented sensors offer promising new tools for modern environmental research.

  11. Detecting river sediments to assess hazardous materials at volcanic lake using advanced remote sensing techniques

    NASA Astrophysics Data System (ADS)

    Saepuloh, Asep; Fitrianingtyas, Chintya

    2016-05-01

    The Toba Caldera formed from large depression of Quaternary volcanism is a remarkable feature at the Earth surface. The last Toba super eruptions were recorded around 73 ka and produced the Youngest Toba Tuff about 2,800 km3. Since then, there is no record of significant volcanic seismicity at Toba Volcanic Complex (TVC). However, the hydrothermal activities are still on going as presented by the existence of hot springs and alteration zones at the northwest caldera. The hydrothermal fluids probably containing some chemical compositions mixed with surficial water pollutant and contaminated the Toba Lake. Therefore, an environmental issues related to the existence of chemical composition and degradation of water clearness in the lake had been raised in the local community. The pollutant sources are debatable between natural and anthropogenic influences because some human activities grow rapidly at and around the lake such as hotels, tourisms, husbandry, aquaculture, as well as urbanization. Therefore, obtaining correct information about the source materials floating at the surface of the Toba Lake is crucial for environmental and hazard mitigation purposes. Overcoming the problem, we presented this paper to assess the source possibility of floating materials at Toba Lake, especially from natural sources such as hydrothermal activities of TVC and river stream sediments. The Spectral Angle Mapper (SAM) techniques using atmospherically corrected of Landsat-8 and colour composite of Polarimetric Synthetic Aperture Radar (PolSAR) were used to map the distribution of floating materials. The seven ground truth points were used to confirm the correctness of proposed method. Based on the SAM and PolSAR techniques, we could detect the interface of hydrothermal fluid at the lake surfaces. Various distributions of stream sediment were also detected from the river mouth to the lake. The influence possibilities of the upwelling process from the bottom floor of Toba Lake were also

  12. Study of Influence of Effluent on Ground Water Using Remote Sensing, GIS and Modeling Techniques

    NASA Astrophysics Data System (ADS)

    Pathak, S.; Bhadra, B. K.; Sharma, J. R.

    2012-07-01

    The area lies in arid zone of western Rajasthan having very scanty rains and very low ground water reserves. Some of the other problems that are faced by the area are disposal of industrial effluent posing threat to its sustainability of water resource. Textiles, dyeing and printing industries, various mechanical process and chemical/synthetic dyes are used and considerable wastewater discharged from these textile units contains about high amount of the dyes into the adjoining drainages. This has caused degradation of water quality in this water scarce semi-arid region of the country. Pali city is located South-West, 70 Kms from Jodhpur in western Rajasthan (India). There are four Common Effluent Treatment Plant (CETP) treating wastewater to meet the pollutant level permissible to river discharge, a huge amount of effluent water of these factories directly meets the into the river Bandi - a tributary of river Luni. In order to monitor the impact of industrial effluents on the environment, identifying the extent of the degradation and evolving possible means of minimizing the impacts studies on quality of effluents, polluted river water and water of adjoining wells, the contamination migration of the pollutants from the river to ground water were studied. Remote sensing analysis has been carried out using Resourcesat -1 multispectral satellite data along with DEM derived from IRS P5 stereo pair. GIS database generated of various thematic layers viz. base layer - inventorying all waterbodies in the vicinity, transport network and village layer, drainage, geomorphology, structure, land use. Analysis of spatial distribution of the features and change detection in land use/cover carried out. GIS maps have been used to help factor in spatial location of source and hydro-geomorphological settings. DEM & elevation contour helped in delineation of watershed and identifying flow modelling boundaries. Litholog data analysis carried out for aquifer boundaries using specialized

  13. Applying satellite remote sensing technique in disastrous rainfall systems around Taiwan

    NASA Astrophysics Data System (ADS)

    Liu, Gin-Rong; Chen, Kwan-Ru; Kuo, Tsung-Hua; Liu, Chian-Yi; Lin, Tang-Huang; Chen, Liang-De

    2016-05-01

    Many people in Asia regions have been suffering from disastrous rainfalls year by year. The rainfall from typhoons or tropical cyclones (TCs) is one of their key water supply sources, but from another perspective such TCs may also bring forth unexpected heavy rainfall, thereby causing flash floods, mudslides or other disasters. So far we cannot stop or change a TC route or intensity via present techniques. Instead, however we could significantly mitigate the possible heavy casualties and economic losses if we can earlier know a TC's formation and can estimate its rainfall amount and distribution more accurate before its landfalling. In light of these problems, this short article presents methods to detect a TC's formation as earlier and to delineate its rainfall potential pattern more accurate in advance. For this first part, the satellite-retrieved air-sea parameters are obtained and used to estimate the thermal and dynamic energy fields and variation over open oceans to delineate the high-possibility typhoon occurring ocean areas and cloud clusters. For the second part, an improved tropical rainfall potential (TRaP) model is proposed with better assumptions then the original TRaP for TC rainfall band rotations, rainfall amount estimation, and topographic effect correction, to obtain more accurate TC rainfall distributions, especially for hilly and mountainous areas, such as Taiwan.

  14. A study and evaluation of image analysis techniques applied to remotely sensed data

    NASA Technical Reports Server (NTRS)

    Atkinson, R. J.; Dasarathy, B. V.; Lybanon, M.; Ramapriyan, H. K.

    1976-01-01

    An analysis of phenomena causing nonlinearities in the transformation from Landsat multispectral scanner coordinates to ground coordinates is presented. Experimental results comparing rms errors at ground control points indicated a slight improvement when a nonlinear (8-parameter) transformation was used instead of an affine (6-parameter) transformation. Using a preliminary ground truth map of a test site in Alabama covering the Mobile Bay area and six Landsat images of the same scene, several classification methods were assessed. A methodology was developed for automatic change detection using classification/cluster maps. A coding scheme was employed for generation of change depiction maps indicating specific types of changes. Inter- and intraseasonal data of the Mobile Bay test area were compared to illustrate the method. A beginning was made in the study of data compression by applying a Karhunen-Loeve transform technique to a small section of the test data set. The second part of the report provides a formal documentation of the several programs developed for the analysis and assessments presented.

  15. Optimal spatial sampling techniques for ground truth data in microwave remote sensing of soil moisture

    NASA Technical Reports Server (NTRS)

    Rao, R. G. S.; Ulaby, F. T.

    1977-01-01

    The paper examines optimal sampling techniques for obtaining accurate spatial averages of soil moisture, at various depths and for cell sizes in the range 2.5-40 acres, with a minimum number of samples. Both simple random sampling and stratified sampling procedures are used to reach a set of recommended sample sizes for each depth and for each cell size. Major conclusions from statistical sampling test results are that (1) the number of samples required decreases with increasing depth; (2) when the total number of samples cannot be prespecified or the moisture in only one single layer is of interest, then a simple random sample procedure should be used which is based on the observed mean and SD for data from a single field; (3) when the total number of samples can be prespecified and the objective is to measure the soil moisture profile with depth, then stratified random sampling based on optimal allocation should be used; and (4) decreasing the sensor resolution cell size leads to fairly large decreases in samples sizes with stratified sampling procedures, whereas only a moderate decrease is obtained in simple random sampling procedures.

  16. Satellite Remote Sensing with Artificial Neural Network Modeling Techniques for Water Quality Monitoring

    NASA Astrophysics Data System (ADS)

    Kuo, Y. C.; Chen, C. F.

    2016-12-01

    The analyzed parameters of the water quality samples in Lake Nicaragua and Lake Managua include basic physical and chemical water quality parameters, nutrients, bacteria and zooplankton index, heavy metals and organic compounds in the sediments etc. 5 parameters are tested to assess lake eutrophication. To associate with satellite data, the analysis is aim to establish a set of mathematical transformations to convert the model spectra of satellite imagery reactions on water quality parameters and further to calculate the concentration of the parameters in both lakes. The sampling period took place during the rainy season. The high cloud-covered satellite imagery did not provide a completed available data for the analysis. Therefore, we used mathematical techniques to remake an image which contains a completed lake areas. Following by using linear equation to build the water quality models, the results suggested that the testing of chlorophyll in the model performance was the most accurate, and then the suspended solids, total phosphorus and total nitrogen. Fecal colon bacilli, of all parameters, has the worst performance in testing accuracy.

  17. Remote sensing of atmospheric SO2 using the differential absorption LIDAR technique

    NASA Technical Reports Server (NTRS)

    Hoell, J. M., Jr.; Wade, W. R.; Thompson, R. T., Jr.

    1976-01-01

    The paper reports an investigation of the capabilities of a UV differential absorption lidar (DIAL) system for remote measurements of sulfur dioxide emissions. Two features of the present DIAL system are an absorption cell permitting the determination of the difference in SO2 absorption coefficients for the two transmitted wavelengths and a calibration cell permitting the linearity and performance of the system to be evaluated. The DIAL technique is described along with the transmitter, receiver, data-adquisition, and data-processing components of the investigated system. Quantitative measurements of the average SO2 concentration in a region surrounding the exhaust stack of a steam-generating plant are discussed which show that the present system has measurement sensitivities of 10 ppb at a range of 0.8 km and 20 ppb at 1.9 km. Based on performance characteristics obtained during a calibration of this system, it is predicted that a measurement sensitivity of less than 4 ppb over a 1-km path will be attained.

  18. Monitoring bacterial growth using tunable resistive pulse sensing with a pore-based technique.

    PubMed

    Yu, Allen C S; Loo, Jacky F C; Yu, Samuel; Kong, S K; Chan, Ting-Fung

    2014-01-01

    A novel bacterial growth monitoring method using a tunable resistive pulse sensor (TRPS) system is introduced in this study for accurate and sensitive measurement of cell size and cell concentration simultaneously. Two model bacterial strains, Bacillus subtilis str.168 (BSU168) and Escherichia coli str.DH5α (DH5α), were chosen for benchmarking the growth-monitoring performance of the system. Results showed that the technique of TRPS is sensitive and accurate relative to widely used methods, with a lower detection limit of cell concentration measurement of 5 × 10⁵ cells/ml; at the same time, the mean coefficient of variation from TRPS was within 2 %. The growth of BSU168 and DH5α in liquid cultures was studied by TRPS, optical density (OD), and colony plating. Compared to OD measurement, TRPS-measured concentration correlates better with colony plating (R = 0.85 vs. R = 0.72), which is often regarded as the gold standard of cell concentration determination. General agreement was also observed by comparing TRPS-derived cell volume measurements and those determined from microscopy. We have demonstrated that TRPS is a reliable method for bacterial growth monitoring, where the study of both cell volume and cell concentration are needed to provide further details about the physical aspects of cell dynamics in real time.

  19. Optimal spatial sampling techniques for ground truth data in microwave remote sensing of soil moisture

    NASA Technical Reports Server (NTRS)

    Rao, R. G. S.; Ulaby, F. T.

    1977-01-01

    The paper examines optimal sampling techniques for obtaining accurate spatial averages of soil moisture, at various depths and for cell sizes in the range 2.5-40 acres, with a minimum number of samples. Both simple random sampling and stratified sampling procedures are used to reach a set of recommended sample sizes for each depth and for each cell size. Major conclusions from statistical sampling test results are that (1) the number of samples required decreases with increasing depth; (2) when the total number of samples cannot be prespecified or the moisture in only one single layer is of interest, then a simple random sample procedure should be used which is based on the observed mean and SD for data from a single field; (3) when the total number of samples can be prespecified and the objective is to measure the soil moisture profile with depth, then stratified random sampling based on optimal allocation should be used; and (4) decreasing the sensor resolution cell size leads to fairly large decreases in samples sizes with stratified sampling procedures, whereas only a moderate decrease is obtained in simple random sampling procedures.

  20. Runoff simulation using distributed hydrological modeling approach, remote sensing and GIS techniques: A case study from an Indian agricultural watershed

    NASA Astrophysics Data System (ADS)

    Chowdary, V. M.; Desai, V. R.; Gupta, M.; Jeyaram, A.; Murthy, Y. V. N. K.

    2012-07-01

    Distributed hydrological modeling has the capability of simulating distributed watershed basin processes, by dividing a heterogeneous and complex land surface divided into computational elements such as Hydrologic Response Units (HRU), grid cell or sub watersheds. The present study was taken up to simulate spatial hydrological processes from a case study area of Kansavati watershed in Purulia district of West Bengal, India having diverse geographical features using distributed hydrological modelling approach. In the present study, overland flow in terms of direct runoff from storm rainfall was computed using USDA Soil Conservation Services (SCS) curve number technique and subsequently it served as input to channel routing model. For channel flow routing, Muskingum-Cunge flood routing technique was used, specifically to route surface runoff from the different sub watershed outlet points to the outlet point of the watershed. Model parameters were derived for each grid cell either from remote sensing data or conventional maps under GIS environment. For distributed approach, validation show reasonable fit between the simulated and measured data and CMR value in all the cases is negative and ranges from -0.1 to - 0.3. Further, this study investigates the effect of cell size on runoff simulation for different grid cell sizes of 23, 46, 92, 184, 368, 736, 1472 m resolution. The difference between simulated and observed runoff values increases with the increase of grid size beyond 184 m more prominently. Further, this model can be used to evaluate futuristic water availability scenarios for an agricultural watershed in eastern India.

  1. Romantic versus scientific perspective: the ruins of Radlin palace in Wielkopolska region in the light of remote sensing techniques

    NASA Astrophysics Data System (ADS)

    Wilgocka, Aleksandra; Ruciński, Dominik; RÄ czkowski, Włodzimierz

    2015-06-01

    Although ruins of palace in Radlin, localized in Wielkopolska Region (Poland), could have been a great inspiration for romantic landscape painters, they were hardly considered as the subject of artistic interest. Nevertheless they stand as a marker in a landscape as a romantic background for the village on one hand and a memento for the neighbouring graveyard on another. Small scale excavations carried out in late 1950s with historical maps and analysis of still standing remains gave a general idea about wings order, localisation of main entrance and communication routs inside courtyard. Those early research thereby were the first step to change the meaning of this place from romantic to more scientific. New remote sensing technology allows move even further into scientific direction. The ruins in Radlin have been included into project ArchEO - archaeological applications of Earth Observation techniques. The main aim of the project in case of Radlin is an attempt to answer the question to what extent very high resolution optical satellite imagery might allow better understanding the spatial structure of the place. The various processing techniques were applied to facilitate the detection of archaeological features' impact on the vegetation condition. It enabled to assess the usefulness of satellite based data in recognizing specific archaeological remains. Thus, potential and limitations of satellite imagery versus other sources of spatial information like historic maps, excavation results, aerial photographs and Lidar will be discussed.

  2. Using Remote Sensing Techniques to Measure Chl:C in the Santa Barbara Channel

    NASA Astrophysics Data System (ADS)

    Taylor, N.; Bausell, J.; Bell, T. W.; Kudela, R. M.; Scuderi, L. A.

    2016-12-01

    Giant Kelp (Macrocystis pyrifera) is an important primary producer along the west coast of North America. It provides critical habitat to a wide range of marine organisms. While satellite sensors can easily quantify canopy area of kelp, using similar techniques to gauge the physiological health of these macroalgae has proven more difficult. Bell et al. (2015) devised an algorithm that effectively estimated the chlorophyll to carbon ratio (Chl:C)—a proxy for kelp health—using AVIRIS imagery. A comparison of AVIRIS imagery of the Isla Vista kelp bed sampled in 2013 and 2015, before and during the recent El Nino-associated west coast `warm anomaly', indicates a decline in Chl:C in 2015 (student t-test p<0.01). The lower Chl:C of Isla Vista observed in 2015 could be caused by environmental stressors associated with El Niño such as increased sea surface temperature, decreased nutrient availability, and disturbance. However while AVIRIS imagery shows great potential in mapping kelp forest health, as an airborne sensor its availability is inconsistent over time, making it less ideal for continuous kelp forest monitoring. We therefore attempt to extend this method of determining Chl:C based on reflectance values to Landsat 8 satellite imagery. We found that although USGS Landsat 8 atmospherically corrected reflectance data does not accurately estimate kelp health, simulated Landsat 8 data from an AVIRIS image does. This suggests that although the spectral resolution of Landsat 8 is much lower than AVIRIS, with sufficient atmospheric correction the satellite will be able to classify kelp health.

  3. Comparing Remote Sensing Techniques in Detecting Salmonid Habitat, Salmon River, Oregon

    NASA Astrophysics Data System (ADS)

    Shintani, C. M.

    2015-12-01

    Many restoration projects in the Pacific Northwest are implemented to improve habitat quality, quantity, and complexity for fish. Although numerous engineered log structures have been constructed in the hopes of achieving these goals, relatively few projects have been rigorously monitored to determine their success. This research seeks to compare the utility and application between photogrammetric and spectral depth approaches in detecting fish habitat in order to determine which method is more accurate and affordable for monitoring channel bathymetry. While each of these techniques has been individually studied, previous research has not directly compared and quantified their differences. Channel bathymetry data were collected by combining pre- and post-restoration digital photographs of the Salmon River in Northeast Clackamas County, Oregon, using structure-from-motion (SfM). The resulting 3D point cloud will be used to estimate water depths using photogrammetry and spectral depth. The photogrammetric method applies a refraction correction to the extracted water depth from the SfM topography to derive water depth. A regression between the surveyed water depth values and digital number values of surface pixels will derive depth. The resulting water depths from these two methods will be compared to the surveyed water depths for their accuracy and precision, particularly in critical salmonid habitats. The quantification of these differences will be an important contribution to river restoration science as it will allow for more accurate measurement and monitoring of changes in fish habitat. In the future, these data will be used in an eco-hydraulic River2D model to simulate changes in salmonid habitat availability after restoration.

  4. Efficiencies of Rotational Raman, and Rayleigh Techniques for Laser Remote Sensing of the Atmospheric Temperature

    NASA Technical Reports Server (NTRS)

    Ivanova, I. D.; Gurdev, L. L.; Mitev, V. M.

    1992-01-01

    Various lidar methods have been developed for measuring the atmospheric temperature, making use of the temperature dependant characteristics of rotational Raman scattering (RRS) from nitrogen and oxygen, and Rayleigh or Rayleigh-Brillowin scattering (RS or RBS). These methods have various advantages and disadvantages as compared to each other but their potential accuracies are principal characteristics of their efficiency. No systematic attempt has been undertaken so far to compare the efficiences, in the above meaning, of different temperature lidar methods. Two RRS techniques have been compared. Here, we do such a comparison using two methods based on the detection and analysis of RS (RBS) spectra. Four methods are considered here for measuring the atmospheric temperature. One of them (Schwiesow and Lading, 1981) is based on an analysis of the RS linewidth with two Michelson interferometers (MI) in parallel. The second method (Shimisu et al., 1986) employs a high-resolution analysis of the RBS line shape. The third method (Cooney, 1972) employs the temperature dependance of the RRS spectrum envelope. The fourth method (Armstrong, 1974) makes use of a scanning Fabry-Perot interferometer (FPI) as a comb filter for processing the periodic RRS spectrum of the nitrogen. Let us denote the corresponding errors in measuring the temperature by sigma(sub MI), sigma(sub HR), sigma(sub ENV), and sigma(sub FPI). Let us also define the ratios chi(sub 1) = sigma(sub MI)/sigma(sub ENV), chi(sub 2) = sigma(sub HR)/sigma(sub ENV), and chi(sub 3) = sigma(sub FPI)/sigma(sub ENV) interpreted as relative errors with respect to sigma(sub ENV).

  5. Monitoring of Emissions From a Refinery Tank Farm Using a Combination of Optical Remote Sensing Techniques

    NASA Astrophysics Data System (ADS)

    Polidori, A.; Tisopulos, L.; Pikelnaya, O.; Mellqvist, J.; Samuelsson, J.; Marianne, E.; Robinson, R. A.; Innocenti, F.; Finlayson, A.; Hashmonay, R.

    2016-12-01

    Despite great advances in reducing air pollution, the South Coast Air Basin (SCAB) still faces challenges to attain federal health standards for air quality. Refineries are large sources of ozone precursors and, hence contribute to the air quality problems of the region. Additionally, petrochemical facilities are also sources of other hazardous air pollutants (HAP) that adversely affect human health, for example aromatic hydrocarbons. In order to assure safe operation, decrease air pollution and minimize population exposure to HAP the South Coast Air Quality Management District (SCAQMD) has a number of regulations for petrochemical facilities. However, significant uncertainties still exist in emission estimates and traditional monitoring techniques often do not allow for real-time emission monitoring. In the fall of 2015 the SCAQMD, Fluxsense Inc., the National Physical Laboratory (NPL), and Atmosfir Optics Ltd. conducted a measurement study to characterize and quantify gaseous emissions from the tank farm of one of the largest oil refineries in the SCAB. Fluxsense used a vehicle equipped with Solar Occultation Flux (SOF), Differential Optical Absorption Spectroscopy (DOAS), and Extractive Fourier Transform Infrared (FTIR) spectroscopy instruments. Concurrently, NPL operated their Differential Absorption Lidar (DIAL) system. Both research groups quantified emissions from the entire tank farm and identified fugitive emission sources within the farm. At the same time, Atmosfir operated an Open Path FTIR (OP-FTIR) spectrometer along the fenceline of the tank farm. During this presentation we will discuss the results of the emission measurements from the tank farm of the petrochemical facility. Emission rates resulting from measurements by different ORS methods will be compared and discussed in detail.

  6. Making sense of geoscientific concepts using active pedagogy techniques, a technology aided experience

    NASA Astrophysics Data System (ADS)

    Huguet, C.; Noè, L. F.; Pearse, J.; Gómez Pérez, M.; Valencia Lopez, D.; Jimenez Heredia, A.; Patiño Avedaño, M.

    2016-12-01

    This work is the result of a teaching innovation project funded by the Conecta-TE unit at Universidad de los Andes, Bogotá, Colombia and results from the collaborative work of a team of geoscience professors and pedagogic and technical support experts. The need for this innovation stems from the constraints of teaching an applied science subject to a large cohort of approximately 500 students per semester in five sections which makes it impossible to include laboratories or scientific outings. These factors are compounded by the fact this is an introductory core course for Geoscience but also a service course that can be taken by any student on campus whether they have a scientific background or not. Therefore our aim was double: making the basic concepts more understandable for a broad audience, while at the same time maintaining a sufficiently high level to challenge and form a sound basis for students from the Geosciences program. Additionally we wanted to incorporate more active and practical aspects to the subject in order to enhance student learning. This in itself was challenging with groups of over 90 students. Data on student understanding and satisfaction were collected both in classes where the innovation was implemented and others in which it was not. Generally our innovation was positively rated, however the students perceived that it involved more work than the traditional lecture-based classes, but they preferred the continual assessment to traditional homework. The methodology was improved and implemented fully for the second round of teaching by introducing the methodology and objectives more clearly. In the future we expect to reduce the number of activities per class (the ´less-is-more' approach) whilst at the same time increasing the amount of classes which include active learning techniques. The ultimate goal is to extend the experience from the two current sections to all five sections of the course.

  7. A New Technique For Quantifying Effusive Volcanic Activity at Tolbachik Volcano Using Multiple Remote Sensing Platforms

    NASA Astrophysics Data System (ADS)

    McAlpin, D. B.; Meyer, F. J.; Dehn, J.; Webley, P. W.

    2016-12-01

    In 1976, "The Great Tolbachik Fissure Eruption," became the largest basaltic eruption in the recorded history of the Kamchatka Peninsula. In November 2012, after thirty-six years of quiescence, Tolbachik again erupted, and continued for nine months until its end in August, 2013. Observers of the 2012-13 eruption reported a mostly effusive eruption from two main fissures, long, rapidly moving lava flows, and ash clouds of up to 6 km. Initial estimates of effusive activity reported an approximate volume of 0.52 km³ over an area of more than 35 km². In this analysis, we provide updated effusion estimates for the Tolbachik eruption, determined by thermal data acquired by the Advanced Very High Resolution Radiometer (AVHRR) satellites. Each of the four AVHRR satellites carries a broad-band, five channel sensor that acquires data in the visible and infrared portions of the electromagnetic spectrum, with each satellite completing 14 daily Earth orbits. A critical component to the volume estimates is a determination of fissure size and the area of lava flow at different times during the eruption. For this purpose, we acquired optical satellite images obtained from three orbiting platforms: the Advanced Land Imager (ALI),) aboard the Earth Observer-1 (EO-1) satellite, the Operational Land Imager (OLI) aboard Landsat 8, and the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) aboard NASA's Terra satellite. From these multiple platforms, lava flow maps were prepared from repeat acquisitions over the course of the eruption. Periodic lava flow measurements clarify effusion rates as instantaneous discharge rates, mean effusion rates over time, and an overall effusion rate over the entire eruption. Given the natural limitations of effusion estimates derived from thermal data, our results are compared to effusion estimates derived by DEM differencing to evaluate accuracy. This analysis is a true multi-sensor technique that affords a method to rapidly

  8. Remote sensing of auroral E region plasma structures by radio, radar, and UV techniques at solar minimum

    SciTech Connect

    Basu, S.; Valladares, C.E. ); Basu, S.; Eastes, R.; Huffman, R.E. ); Daniell, R.E. ); Chaturvedi, P.K. ); Livingston, R.C. )

    1993-02-01

    The unique capability of the Polar BEAR satellite to simultaneously image auroral luminosities at multiple ultraviolet (UV) wavelengths and to remote sense large-scale (hundreds to tens of kilometers) and small-scale (kilometers to hundreds of meters) plasma density structures with its multifrequency beacon package is utilized to probe the auroral E region in the vicinity of the incoherent scatter radar (ISR) facility near Sondrestrom. In particular, we present coordinated observations on two nights obtained during the sunspot minimum (sunspot number < 10) January-February 1987 period when good spatial and temporal conjunction was obtained between Polar BEAR overflights and Sondrestrom ISR measurements. With careful coordinated observations we were able to confirm that the energetic particle precipitation responsible for the UV emissions causes the electron density increases in the E region. The integrations up to the topside of these ISR electron density profiles were consistent with the total electron content (TEC) measured by the Polar BEAR satellite. An electron transport model was utilized to determine quantitatively the electron density profiles which could be produced by the particle precipitation, which also produced multiple UV emissions measured by the imager; these profiles were found to be in good agreement with the observed ISR profiles in the E region. This outer scale size is also consistent with the measured phase to amplitude scintillation ratio. An estimate of the linear growth rate of the gradient-drift instability in the E region shows that these plasma density irregularities could have been generated by this process. The mutual consistency of these different sets of measurements provides confidence in the ability of the different techniques to remote sense large- and small-scale plasma density structures in the E region at least during sunspot minimum when the convection-dominated high-latitude F region is fairly weak. 56 refs., 16 figs.

  9. An Integrated Use of Experimental, Modeling and Remote Sensing Techniques to Investigate Carbon and Phosphorus Dynamics in the Humid Tropics

    NASA Technical Reports Server (NTRS)

    Townsend, Alan R.; Asner, Gregory P.; Bustamante, Mercedes M. C.

    2001-01-01

    Moist tropical forests comprise one of the world's largest and most diverse biomes, and exchange more carbon, water, and energy with the atmosphere than any other ecosystem. In recent decades, tropical forests have also become one of the globe's most threatened biomes, subjected to exceptionally high rates of deforestation and land degradation. Thus, the importance of and threats to tropical forests are undeniable, yet our understanding of basic ecosystem processes in both intact and disturbed portions of the moist tropics remains poorer than for almost any other major biome. Our approach in this project was to take a multi-scale, multi-tool approach to address two different problems. First, we wanted to test if land-use driven changes in the cycles of probable limiting nutrients in forest systems were a key driver in the frequently observed pattern of declining pasture productivity and carbon stocks. Given the enormous complexity of land use change in the tropics, in which one finds a myriad of different land use types and intensities overlain on varying climates and soil types, we also wanted to see if new remote sensing techniques would allow some novel links between parameters which could be sensed remotely, and key biogeochemical variables which cannot. Second, we addressed to general questions about the role of tropical forests in the global carbon cycle. First, we used a new approach for quantifying and minimizing non-biological artifacts in the NOAA/NASA AVHRR Pathfinder time series of surface reflectance data so that we could address potential links between Amazonian forest dynamics and ENSO cycles. Second, we showed that the disequilibrium in C-13 exchanged between land and atmosphere following tropical deforestation probably has a significant impact on the use of 13-CO2 data to predict regional fluxes in the global carbon cycle.

  10. Lineament Mapping using Remote Sensing Techniques and Structural Geology for Carbon Dioxide Sequestration Site Characterization in Central New York State

    NASA Astrophysics Data System (ADS)

    Zelazny, Melissa Maria

    2011-12-01

    This study identified lineaments from satellite images and Digital Elevation Models (DEMs) utilizing image processing techniques that enhance variations in spectral and spatial reflectivity and topography. In flat-lying sedimentary sequences Lineaments are commonly surface expressions of tectonic fractures and faults in the bedrock, emphasized on the surface by topography, drainage, and vegetation - many can be identified by remotely sensed data. Knowledge of fault locations can prevent unsuitable site selection for CO2 sequestration where CO2 could migrate up fault systems. Lineament patterns also give insight into the fracture fabric of the region- an important consideration for CO2 sequestration. Various data sets, including multispectral satellite imagery (Landsat and ASTER) and DEMs, as well as geological data describing fractures, faults, and hydrology, were used to map and validate the lineament distribution in the study area. Linear features were enhanced with tonal, topographic and textural changes by digital image processing of the satellite imagery and DEMs. Lineaments were then extracted manually using ArcMap (ArcGIS 9.2 -- ESRI). Lineaments longer than 1 km were identified, digitized and stored in a geo-database together with attributes describing their length, orientation and other characteristics. Lineament categories included vegetation, drainage, and topography. Rose diagrams and statistics of length and number of lineaments in each 100 orientation bin were used to characterize the lineament distribution in each remotely sensed data set. The primary lineament orientations from both ASTER imagery and topography trended northeast and northwest in the study area of central New York State. These trends agreed with some of the EarthSat (1997) lineament sets from Landsat images and also corresponded to some published fracture and fault systems but do not reflect the most abundant sets.

  11. A new strategy for snow-cover mapping using remote sensing data and ensemble based systems techniques

    NASA Astrophysics Data System (ADS)

    Roberge, S.; Chokmani, K.; De Sève, D.

    2012-04-01

    The snow cover plays an important role in the hydrological cycle of Quebec (Eastern Canada). Consequently, evaluating its spatial extent interests the authorities responsible for the management of water resources, especially hydropower companies. The main objective of this study is the development of a snow-cover mapping strategy using remote sensing data and ensemble based systems techniques. Planned to be tested in a near real-time operational mode, this snow-cover mapping strategy has the advantage to provide the probability of a pixel to be snow covered and its uncertainty. Ensemble systems are made of two key components. First, a method is needed to build an ensemble of classifiers that is diverse as much as possible. Second, an approach is required to combine the outputs of individual classifiers that make up the ensemble in such a way that correct decisions are amplified, and incorrect ones are cancelled out. In this study, we demonstrate the potential of ensemble systems to snow-cover mapping using remote sensing data. The chosen classifier is a sequential thresholds algorithm using NOAA-AVHRR data adapted to conditions over Eastern Canada. Its special feature is the use of a combination of six sequential thresholds varying according to the day in the winter season. Two versions of the snow-cover mapping algorithm have been developed: one is specific for autumn (from October 1st to December 31st) and the other for spring (from March 16th to May 31st). In order to build the ensemble based system, different versions of the algorithm are created by varying randomly its parameters. One hundred of the versions are included in the ensemble. The probability of a pixel to be snow, no-snow or cloud covered corresponds to the amount of votes the pixel has been classified as such by all classifiers. The overall performance of ensemble based mapping is compared to the overall performance of the chosen classifier, and also with ground observations at meteorological

  12. Structural Analysis for Gold Mineralization Using Remote Sensing and Geochemical Techniques in a GIS Environment: Island of Lesvos, Hellas

    SciTech Connect

    Rokos, D. Argialas, D. Mavrantza, R. St Seymour, K.; Vamvoukakis, C.; Kouli, M.; Lamera, S.; Paraskevas, H.; Karfakis, I.; Denes, G

    2000-12-15

    Exploration for epithermal Au has been active lately in the Aegean Sea of the eastern Mediterranean Basin, both in the islands of the Quaternary arc and in those of the back-arc region. The purpose of this study was the structural mapping and analysis for a preliminary investigation of possible epithermal gold mineralization, using remotely sensed data and techniques, structural and field data, and geochemical information, for a specific area on the Island of Lesvos. Therefore, Landsat-TM and SPOT-Pan satellite images and the Digital Elevation Model (DEM) of the study area were processed digitally using spatial filtering techniques for the enhancement and recognition of the geologically significant lineaments, as well as algebraic operations with band ratios and Principal Component Analysis (PCA), for the identification of alteration zones. Statistical rose diagrams and a SCHMIDT projection Stereo Net were generated from the lineament maps and the collected field data (dip and strike measurements of faults, joints, and veins), respectively. The derived lineament map and the band ratio images were manipulated in a GIS environment, in order to study the relation of the tectonic pattern to both the alteration zoning and the geomorphology of the volcanic field of the study area. Target areas of high interest for possible mineralization also were specified using geochemical techniques, such as X-Ray Diffraction (XRD) analysis, trace-element, and fluid-inclusion analysis. Finally, preliminary conclusions were derived about possible mineralization, the type (high or low sulfidation), and the extent of mineralization, by combining the structural information with geochemical information.

  13. Mapping of groundwater potential zones in Salem Chalk Hills, Tamil Nadu, India, using remote sensing and GIS techniques.

    PubMed

    Thilagavathi, N; Subramani, T; Suresh, M; Karunanidhi, D

    2015-04-01

    This study proposes to introduce the remote sensing and geographic information system (GIS) techniques in mapping the groundwater potential zones. Remote sensing and GIS techniques have been used to map the groundwater potential zones in Salem Chalk Hills, Tamil Nadu, India. Charnockites and fissile hornblende biotite gneiss are the major rock types in this region. Dunites and peridodites are the ultramafic rocks which cut across the foliation planes of the gneisses and are highly weathered. It comprises magnesite and chromite deposits which are excavated by five mining companies by adopting bench mining. The thickness of weathered and fracture zone varies from 2.2 to 50 m in gneissic formation and 5.8 to 55 m in charnockite. At the contacts of gneiss and charnockite, the thickness ranges from 9.0 to 90.8 m favoring good groundwater potential. The mine lease area is underlined by fractured and sheared hornblende biotite gneiss where groundwater potential is good. Water catchment tanks in this area of 5 km radius are small to moderate in size and are only seasonal. They remain dry during summer seasons. As perennial water resources are remote, the domestic and agricultural activities in this region depend mainly upon the groundwater resources. The mines are located in gently slope area, and accumulation of water is not observed except in mine pits even during the monsoon period. Therefore, it is essential to map the groundwater potential zones for proper management of the aquifer system. Satellite imageries were also used to extract lineaments, hydrogeomorphic landforms, drainage patterns, and land use, which are the major controlling factors for the occurrence of groundwater. Various thematic layers pertaining to groundwater existence such as geology, geomorphology, land use/land cover, lineament, lineament density, drainage, drainage density, slope, and soil were generated using GIS tools. By integrating all the above thematic layers based on the ranks and

  14. Sun Photometer Laser and Lamp Based Radiometric Calibrations; Comparison with the Langley Technique and Implications on Remote Sensing

    NASA Astrophysics Data System (ADS)

    Souaidia, N.; Pietras, C.; Brown, S. W.; Lykke, K. R.; Frouin, R.; Deschamps, P.; Fargion, G.; Johnson, B. C.

    2002-12-01

    Satellite-based remote sensing of the earth is a valuable data source for biological and oceanic studies. However when using remote sensing, it is necessary to correct the measured signal for atmospheric effects. As aerosols play a major role in atmospheric scattering, correcting algorithms based on Aerosol Optical Thickness (AOT) data have been developed to describe the scattering of radiation by aerosols. AOT data are collected by filter radiometers measuring the solar irradiance. The AOT is then retrieved applying the Beer-Bouger-Lambert Law to those measurements. Two radiometers, called Satellite Validation for Marine Biology and Aerosol Determination (SimbadA), were calibrated in this study. These instruments measure the upwelling radiance from the ocean as well as the solar irradiance, providing information on both marine reflectance and AOT. The goals of this study were to calibrate the radiometers using independent methods, evaluate the uncertainties for each method, and assess the influence of the results in terms of the science requirements. The radiometers were calibrated in irradiance and radiance mode using a monochromatic, laser-illuminated integrating sphere, in radiance mode using two different lamp-illuminated integrating spheres, and in irradiance mode using the Langley technique. First, a limited characterization of the instrument was conducted. The instrument's temporal stability and its spectral out-of-band response were evaluated. The instrument was then calibrated in radiance mode using a laser-illuminated integrating sphere that overfilled its field of view (FOV). The absolute radiance responsivity from this calibration was compared to results from measurements of two calibrated lamp illuminated spheres. The first comparison, with the NIST portable radiometric source (NPR), was a validation as good agreement between the two methods has been reported in previous studies. The second comparison was with the Hardy sphere from the Goddard Space

  15. An integrated study of earth resources in the state of California using remote sensing techniques. [planning and management of water resources

    NASA Technical Reports Server (NTRS)

    Colwell, R. N.; Churchman, C. W.; Burgy, R. H.; Schubert, G.; Estes, J. E.; Bowden, L. W.; Algazi, R.; Coulson, K. L. (Principal Investigator)

    1973-01-01

    The University of California has been conducting an investigation which seeks to determine the usefulness of modern remote sensing techniques for studying various components of California's earth resources complex. Most of the work has concentrated on California's water resources, but with some attention being given to other earth resources as well and to the interplay between them and California's water resources.

  16. A Comparison of Two Above-Ground Biomass Estimation Techniques Integrating Satellite-Based Remotely Sensed Data and Ground Data for Tropical and Semiarid Forests in Puerto Rico

    EPA Science Inventory

    Two above-ground forest biomass estimation techniques were evaluated for the United States Territory of Puerto Rico using predictor variables acquired from satellite based remotely sensed data and ground data from the U.S. Department of Agriculture Forest Inventory Analysis (FIA)...

  17. A Comparison of Two Above-Ground Biomass Estimation Techniques Integrating Satellite-Based Remotely Sensed Data and Ground Data for Tropical and Semiarid Forests in Puerto Rico

    EPA Science Inventory

    Two above-ground forest biomass estimation techniques were evaluated for the United States Territory of Puerto Rico using predictor variables acquired from satellite based remotely sensed data and ground data from the U.S. Department of Agriculture Forest Inventory Analysis (FIA)...

  18. Applying aerial digital photography as a spectral remote sensing technique for macrophytic cover assessment in small rural streams

    NASA Astrophysics Data System (ADS)

    Anker, Y.; Hershkovitz, Y.; Gasith, A.; Ben-Dor, E.

    2011-12-01

    Although remote sensing of fluvial ecosystems is well developed, the tradeoff between spectral and spatial resolutions prevents its application in small streams (<3m width). In the current study, a remote sensing approach for monitoring and research of small ecosystem was developed. The method is based on differentiation between two indicative vegetation species out of the ecosystem flora. Since when studied, the channel was covered mostly by a filamentous green alga (Cladophora glomerata) and watercress (Nasturtium officinale), these species were chosen as indicative; nonetheless, common reed (Phragmites australis) was also classified in order to exclude it from the stream ROI. The procedure included: A. For both section and habitat scales classifications, acquisition of aerial digital RGB datasets. B. For section scale classification, hyperspectral (HSR) dataset acquisition. C. For calibration, HSR reflectance measurements of specific ground targets, in close proximity to each dataset acquisition swath. D. For habitat scale classification, manual, in-stream flora grid transects classification. The digital RGB datasets were converted to reflectance units by spectral calibration against colored reference plates. These red, green, blue, white, and black EVA foam reference plates were measured by an ASD field spectrometer and each was given a spectral value. Each spectral value was later applied to the spectral calibration and radiometric correction of spectral RGB (SRGB) cube. Spectral calibration of the HSR dataset was done using the empirical line method, based on reference values of progressive grey scale targets. Differentiation between the vegetation species was done by supervised classification both for the HSR and for the SRGB datasets. This procedure was done using the Spectral Angle Mapper function with the spectral pattern of each vegetation species as a spectral end member. Comparison between the two remote sensing techniques and between the SRGB

  19. The possibility of using photogrammetric and remote sensing techniques to model lavaka (gully erosion) development in Madagascar

    NASA Astrophysics Data System (ADS)

    Raveloson, Andrea; Székely, Balázs; Molnár, Gábor; Rasztovits, Sascha

    2013-04-01

    Gully erosion is a worldwide problem for it has a number of undesirable effects and their development is hard to follow. Madagascar is one of the most affected countries for its highlands are densely covered with gullies named lavakas. Lavaka formation and development seems to be triggered by many regional and local causes but the actual reasons are still poorly understood. Furthermore lavakas differ from normal gullies due to their enormous size and special shape. Field surveys are time consuming and data from two-dimensional measurements and pictures (even aerial) might lack major information for morphologic studies. Therefore close range surveying technologies should be used to get three-dimensional information about these unusual and complex features. This contribution discusses which remote sensing and photogrammetric techniques are adequate to survey the development of lavakas, their volume change and sediment budget. Depending on the types and properties (such as volume, depth, shape, vegetation) of the lavaka different methods will be proposed showing pros and cons of each one of them. Our goal is to review techniques to model, survey and analyze lavakas development to better understand the cause of their formation, special size and shape. Different methods are evaluated and compared from field survey through data processing, analyzing cost-effectiveness, potential errors and accuracy for each one of them. For this purpose we will also consider time- and cost-effectiveness of the softwares able to render the images into 3D model as well as the resolution and accuracy of the outputs. Further studies will concentrate on using the three dimensional models of lavakas which will be later on used for geomorphological studies in order to understand their special shape and size. This is ILARG-contribution #07.

  20. Assessment of the capability of remote sensing and GIS techniques for monitoring reclamation success in coal mine degraded lands.

    PubMed

    Karan, Shivesh Kishore; Samadder, Sukha Ranjan; Maiti, Subodh Kumar

    2016-11-01

    The objective of the present study is to monitor reclamation activity in mining areas. Monitoring of these reclaimed sites in the vicinity of mining areas and on closed Over Burden (OB) dumps is critical for improving the overall environmental condition, especially in developing countries where area around the mines are densely populated. The present study evaluated the reclamation success in the Block II area of Jharia coal field, India, using Landsat satellite images for the years 2000 and 2015. Four image processing methods (support vector machine, ratio vegetation index, enhanced vegetation index, and normalized difference vegetation index) were used to quantify the change in vegetation cover between the years 2000 and 2015. The study also evaluated the relationship between vegetation health and moisture content of the study area using remote sensing techniques. Statistical linear regression analysis revealed that Normalized Difference Vegetation Index (NDVI) coupled with Normalized Difference Moisture Index (NDMI) is the best method for vegetation monitoring in the study area when compared to other indices. A strong linear relationship (r(2) > 0.86) was found between NDVI and NDMI. An increase of 21% from 213.88 ha in 2000 to 258.9 ha in 2015 was observed in the vegetation cover of the reclaimed sites for an open cast mine, indicating satisfactory reclamation activity. NDVI results indicated that vegetation health also improved over the years. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Femtosecond laser fabricated multimode fiber sensors interrogated by optical-carrier-based microwave interferometry technique for distributed strain sensing

    NASA Astrophysics Data System (ADS)

    Hua, Liwei; Song, Yang; Huang, Jie; Cheng, Baokai; Zhu, Wenge; Xiao, Hai

    2016-03-01

    A multimode fiber (MMF) based cascaded intrinsic Fabry-Perot interferometers (IFPIs) system is presented and the distributed strain sensing has been experimentally demonstrated by using such system. The proposed 13 cascaded IFPIs have been formed by 14 cascaded reflectors that have been fabricated on a grade index MMF. Each reflector has been made by drawing a line on the center of the cross-section of the MMF through a femtosecond laser. The distance between any two adjacent reflectors is around 100 cm. The optical carrier based microwave interferometry (OCMI) technique has been used to interrogate the MMF based cascaded FPIs system by reading the optical interference information in the microwave domain. The location along with the shift of the interference fringe pattern for each FPI can be resolved though signal processing based on the microwave domain information. The multimode interference showed very little influence to the microwave domain signals. By using such system the strain of 10-4 for each FPI sensor and the spatial resolution of less than 5 cm for the system can be easily achieved.

  2. Monitoring the urban expansion of Athens using remote sensing and GIS techniques in the last 35 years

    NASA Astrophysics Data System (ADS)

    Nikolakopoulos, Konstantinos; Pavlopoulos, Kosmas; Chalkias, Christos; Manou, Dora

    2005-10-01

    During the last thirty-five years the capital of Greece has suffered from an enormous internal immigration. Its population has overpassed the five millions and today almost the half population of Greece is squeezed in Athens metropolitan area. Because of the significant increase of population, the urban expansion in the basin of Athens was also excessive and in some cases catastrophic. Buildings have covered all the free places, new roads have been constructed, the drainage networks have been covered or disappeared and a lot of changes have been occurred to the landforms. The construction of the new airport (Elefterios Venizelos) at the beginning of this decade created a new commercial and urban pole at the eastern part of Athens and the constructive activity has been moved to new areas around the airport. Our aim was to detect and map all the changes that occurred in the urban area, estimate the urban expansion rate and the human interferences in the natural landscape, using GIS and remote sensing techniques. We have used satellite images from three different periods (1973, 1992, 2002) and topographic maps of 1:25.000 scale. The spatial resolution of all the satellite images ranges from 5 to 10 meters and is it acceptable for the monitoring and mapping of the urban growth. Supervised classification and on screen digitizing methods have been used in order to map the changes. Finally the qualitative and quantitative results of this study are presented in this paper.

  3. Remote Sensing and GIS Techniques for Evaluation of Groundwater Quality in Municipal Corporation of Hyderabad (Zone-V), India

    PubMed Central

    Asadi, S. S.; Vuppala, Padmaja; Reddy, M. Anji

    2007-01-01

    Groundwater quality in Hyderabad has special significance and needs great attention of all concerned since it is the major alternate source of domestic, industrial and drinking water supply. The present study monitors the ground water quality, relates it to the land use / land cover and maps such quality using Remote sensing and GIS techniques for a part of Hyderabad metropolis. Thematic maps for the study are prepared by visual interpretation of SOI toposheets and linearly enhanced fused data of IRS-ID PAN and LISS-III imagery on 1:50,000 scale using AutoCAD and ARC/INFO software. Physico-chemical analysis data of the groundwater samples collected at predetermined locations forms the attribute database for the study, based on which, spatial distribution maps of major water quality parameters are prepared using curve fitting method in Arc View GIS software. Water Quality Index (WQI) was then calculated to find the suitability of water for drinking purpose. The overall view of the water quality index of the present study area revealed that most of the study area with > 50 standard rating of water quality index exhibited poor, very poor and unfit water quality except in places like Banjara Hills, Erragadda and Tolichowki. Appropriate methods for improving the water quality in affected areas have been suggested. PMID:17431315

  4. APPLICATION OF REMOTE SENSING TECHNIQUES TO DETERMINE POSSIBLE FLOOD AREAS IN THE CITY OF VILLAHERMOSA, TABASCO, MÉXICO

    NASA Astrophysics Data System (ADS)

    Rosique, L. O.; Prol-Ledesma, R.; Bonome, M. A.

    2009-12-01

    Villahermosa City, Tabasco, is located in southeastern Mexico, between the Grijalva and Carrizal rivers, with an average height of 10 meters above sea level; in addition, it has inner lagoons and an average annual precipitation of 1947 mm. The combination of these characteristics with anthropogenic factors have caused that the city has been affected by floods in different periods since its foundation. The objective of this study is to determine possible flood areas by the analysis of natural and anthropogenic conditions, which are involved in the process, using remote sensing techniques. The final results are presented in a geographic information system (GIS). The analysis was conducted in 3 stages: the first included a supervised classification of satellite images Landsat ETM + for dates before and after the 2007 flood event, with the aim of monitoring the changes in water bodies, to characterize their courses and to describe their dynamics; accuracy evaluation was performed with an error matrix and a 87% accuracy was obtained. The objective during the second stage was to determine the basin characteristics through geomorphological and hydrological analysis. Finally, the last stage consisted on combining the obtained results with an historical analysis of rainfall and streamflow to define the city areas that are likely to be flooded.

  5. Application of remote-sensing techniques to hydrologic studies in selected coal-mine areas of southeastern Kansas

    USGS Publications Warehouse

    Kenny, J.F.; McCauley, J.R.

    1983-01-01

    Disturbances resulting from intensive coal mining in the Cherry Creek basin of southeastern Kansas were investigated using color and color-infrared aerial photography in conjunction with water-quality data from simultaneously acquired samples. Imagery was used to identify the type and extent of vegetative cover on strip-mined lands and the extent and success of reclamation practices. Drainage patterns, point sources of acid mine drainage, and recharge areas for underground mines were located for onsite inspection. Comparison of these interpretations with water-quality data illustrated differences between the eastern and western parts of the Cherry Creek basin. Contamination in the eastern part is due largely to circulation of water from unreclaimed strip mines and collapse features through the network of underground mines and subsequent discharge of acidic drainage through seeps. Contamination in the western part is primarily caused by runoff and seepage from strip-mined lands in which surfaces have frequently been graded and limed but are generally devoid of mature stands of soil-anchoring vegetation. The successful use of aerial photography in the study of Cherry Creek basin indicates the potential of using remote-sensing techniques in studies of other coal-mined regions. (USGS)

  6. Remote sensing and GIS techniques for evaluation of groundwater quality in municipal corporation of Hyderabad (Zone-V), India.

    PubMed

    Asadi, S S; Vuppala, Padmaja; Reddy, M Anji

    2007-03-01

    Groundwater quality in Hyderabad has special significance and needs great attention of all concerned since it is the major alternate source of domestic, industrial and drinking water supply. The present study monitors the ground water quality, relates it to the land use / land cover and maps such quality using Remote sensing and GIS techniques for a part of Hyderabad metropolis. Thematic maps for the study are prepared by visual interpretation of SOI toposheets and linearly enhanced fused data of IRS-ID PAN and LISS-III imagery on 1:50,000 scale using AutoCAD and ARC/INFO software. Physico-chemical analysis data of the groundwater samples collected at predetermined locations forms the attribute database for the study, based on which, spatial distribution maps of major water quality parameters are prepared using curve fitting method in Arc View GIS software. Water Quality Index (WQI) was then calculated to find the suitability of water for drinking purpose. The overall view of the water quality index of the present study area revealed that most of the study area with >50 standard rating of water quality index exhibited poor, very poor and unfit water quality except in places like Banjara Hills, Erragadda and Tolichowki. Appropriate methods for improving the water quality in affected areas have been suggested.

  7. A Low-Power and In Situ Annealing Mitigation Technique for Fast Neutrons Irradiation of Integrated Temperature Sensing Diodes

    SciTech Connect

    Francis, Laurent A.; Andre, Nicolas; Gerard, Pierre; Flandre, Denis; Ali, S. Zeeshan; Udrea, Florin

    2015-07-01

    High doses of fast neutrons is detrimental to the performance of most common solid-state devices such as diodes and transistors. The ionizing effect is observed in particular for diodes used as simple integrated temperature sensors, or thermo-diodes, when their junction voltage is measured at constant current bias. In this work, we present a low-power and in situ mitigation technique based on Silicon-on-Insulator (SOI) micro-hot-plates to recover thermo-diodes. The basic operating principle consists in annealing the temperature-sensitive diodes integrated on the membrane during or after their irradiation in order to restore similar sensing characteristics over time. We measured thermo-diodes integrated to micro-hot-plates during their irradiation by fast neutrons (23 MeV peak) with total doses about 2.97±0.08 kGy. The membrane annealing is taking place at 450 deg. C using 40 mW of electrical power. Thanks to the annealing, the diode keeps a total measurement error below 0.5 deg. C. In this harsh radiation environment and beside the good tolerance of the thermo-diodes and the membrane materials to the total ionizing dose, the thermo-diode located on the heating membrane keeps a constant sensitivity. The demonstrated resistance of micro-hot-plates and the integrated thermo-diodes to fast neutron radiations can extend their use in nuclear plants and for radiation detectors. (authors)

  8. A comparison of the ethanol sensing properties of α-iron oxide nanostructures prepared via the sol-gel and electrospinning techniques

    NASA Astrophysics Data System (ADS)

    Leonardi, S. G.; Mirzaei, A.; Bonavita, A.; Santangelo, S.; Frontera, P.; Pantò, F.; Antonucci, P. L.; Neri, G.

    2016-02-01

    Haematite (α-Fe2O3) nanostructures were synthesized via a Pechini sol-gel method (PSG) and an electrospinning (ES) technique. Their texture and morphology were investigated by scanning and transmission electron microscopy. α-Fe2O3 nanoparticles were obtained by the PSG method, whereas fibrous structures consisting of interconnected particles were synthesized through the ES technique. The crystallinity of the α-Fe2O3 nanostructures was also studied by means of x-ray diffraction and Raman spectroscopy. Gas-sensing devices were fabricated by printing the synthesized samples on ceramic substrates provided with interdigitated Pt electrodes. The sensors were tested towards low concentrations of ethanol in air in the temperature range (200-400°C). The results show that the α-Fe2O3 nanostructures exhibit somewhat different gas-sensing properties and, interestingly, their sensing behaviour is strongly temperature-dependent. The availability of active sites for oxygen chemisorption and the diffusion of the analyte gas within the sensing layer structure are hypothesized to be the key factors responsible for the different sensing behaviour observed.

  9. A comparison of the ethanol sensing properties of α-iron oxide nanostructures prepared via the sol-gel and electrospinning techniques.

    PubMed

    Leonardi, S G; Mirzaei, A; Bonavita, A; Santangelo, S; Frontera, P; Pantò, F; Antonucci, P L; Neri, G

    2016-02-19

    Haematite (α-Fe2O3) nanostructures were synthesized via a Pechini sol-gel method (PSG) and an electrospinning (ES) technique. Their texture and morphology were investigated by scanning and transmission electron microscopy. α-Fe2O3 nanoparticles were obtained by the PSG method, whereas fibrous structures consisting of interconnected particles were synthesized through the ES technique. The crystallinity of the α-Fe2O3 nanostructures was also studied by means of x-ray diffraction and Raman spectroscopy. Gas-sensing devices were fabricated by printing the synthesized samples on ceramic substrates provided with interdigitated Pt electrodes. The sensors were tested towards low concentrations of ethanol in air in the temperature range (200-400 °C). The results show that the α-Fe2O3 nanostructures exhibit somewhat different gas-sensing properties and, interestingly, their sensing behaviour is strongly temperature-dependent. The availability of active sites for oxygen chemisorption and the diffusion of the analyte gas within the sensing layer structure are hypothesized to be the key factors responsible for the different sensing behaviour observed.

  10. Reconstruction of a Tornado Disaster Employing Remote Sensing Techniques: A Case Study of the 1999 Moore, Oklahoma Tornado

    NASA Astrophysics Data System (ADS)

    Wagner, Melissa A.

    Remote sensing has demonstrated to be an instrumental tool in monitoring land changes as a result of anthropogenic change or natural disasters. Most disaster studies have focused on large-scale events with few analyzing small-scale disasters such as tornadoes. These studies have only provided a damage assessment perspective with the continued need to assess reconstruction. This study attempts to fill that void by examining recovery from the 1999 Moore, Oklahoma Tornado utilizing Landsat TM and ETM+ imagery. Recovery was assessed for 2000, 2001 and 2002 using spectral enhancements (vegetative and urban indices and a combination of the two), a recovery index and different statistical thresholds. Classification accuracy assessments were performed to determine the precision of recovery and select the best results. This analysis proved that medium resolution imagery could be used in conjunction with geospatial techniques to capture recovery. The new indices, Shortwave Infrared Index (SWIRI) and Coupled Vegetation and Urban Index (CVUI), developed for disaster management, were the most effective at discerning reconstruction using the 1.5 standard deviation threshold. Recovery rates for F-scale damages revealed that the most incredibly damaged areas associated with an F5 rating were the slowest to recover, while the lesser damaged areas associated with F1-F3 ratings were the quickest to rebuild. These findings were consistent for 2000, 2001 and 2002 also exposing that complete recovery was never attained in any of the F-scale damage zones by 2002. This study illustrates the significance the biophysical impact has on recovery as well as the effectiveness of using medium resolution imagery such as Landsat in future research.

  11. Updating the 1:50.000 geological maps of Rhodes Island using remote sensing data and GIS techniques

    NASA Astrophysics Data System (ADS)

    Tsombos, Panagiotis I.; Nikolakopoulos, Konstantinos G.; Photiades, Adonis; Psonis, Konstantinos

    2007-10-01

    The island of Rhodes represents an uplifted easternmost segment of the Hellenic forearc extending between Greece and Turkey, which is associated with the subduction of the African plate below the Aegean. Middle Miocene-Pleistocene sedimentary basins, are separated by a stack of Alpine nappes of the Hellenide orogen exposed in uplifted fault blocks such as Plattenkalk series (Attaviros Group), Gavrovo-Tripolitza series (Lindos Group), Pindos-Olonos series (Profitis Ilias Group) and several outcrops of Pelagonian series with ophiolitic mélanges. These pre-Neogene formations are dominated by low-grade metamorphic sediments, which were folded and faulted during several phases of the alpine orogeny. The Rhodes region was uplifted in the Middle Miocene after which subsidence and deposition of sediments took place in the Upper Pliocene and Lower Pleistocene. In this paper we present the combined use of remote sensing and GIS techniques for the geological mapping of Rhodes Island at a 1/50.000 scale. The geological formations, geotectonic units and the tectonic structure were recognized in situ and mapped. Interpretation of medium resolution satellite images (Landsat 7 ETM and Terra ASTER) has been carried out in order to detect the linear or not structures of the study area. The in situ mapping was enhanced with data from the digital processing of the satellite data. All the analogical and digital data were imported in a geodata base specially designed for geological data. After the necessary topological control and corrections the data were unified and processed in order to create the final layout at 1/50.000 scale.

  12. Application of optical remote sensing techniques to quantify emissions from urban oil wells, storage tanks, and other small stationary sources

    NASA Astrophysics Data System (ADS)

    Pikelnaya, O.; Polidori, A.; Tisopulos, L.; Mellqvist, J.; Samuelsson, J.; Robinson, R. A.; Innocenti, F.; Perry, S.

    2016-12-01

    Oil fields in the Los Angeles Basin remain very productive even after more than a century-long history of exploration. There are currently over 5,000 active oil wells the South Coast Air Basin (SCAB), with a large portion placed in close proximity of residences, schools and other sensitive receptors. Gaseous emissions from oil wells and equipment related to oil extraction can have a significant impact on air quality. The South Coast Air Quality Management District (SCAQMD) and other state regulatory agencies have a number of rules aimed to reduce Volatile Organic Compound (VOC) emissions and to minimize potential impacts to nearby communities. However, little information is available on the effectiveness of current control measures and magnitude of emissions remain largely unknown. To fill this knowledge gap, in the fall of 2015 the SCAQMD, Fluxsense Inc., the National Physical Laboratory (NPL), and Kassay Field Services Inc. conducted a comprehensive five-week study to measure gaseous emissions from oil wells, oil pumps, intermediate storage tanks, and other small point sources. A combination of optical remote sensing (ORS) techniques was used to detect and quantify emissions VOCs, methane, nitrogen oxides (NOx) and other gaseous pollutants. Fluxsense used Solar Occultation Flux (SOF), Differential Optical Absorption Spectroscopy (DOAS), and Extractive Fourier Transform Infrared (FTIR) spectroscopy to survey a large number of oil extraction sites and other small emission sources within SCAB. Similarly, Kassay Field Services carried out open-path FTIR measurements to complement observations provided by Fluxsense. Concurrently, NPL operated their Differential Absorption Lidar (DIAL) system on a smaller sub-set of sources to validate the emission results provided by Fluxsense and Kassay. During this presentation we will discuss the results of this joined measurement effort and the potential impacts of the observed emissions on neighboring communities. Additionally

  13. Application of remote sensing techniques to study the neotectonics in the northwestern Himalayan fold-and-thrust belt, Pakistan

    NASA Astrophysics Data System (ADS)

    Chen, Lize

    The northwestern Himalayan foreland fold-and-thrust belt in Pakistan is characterized by a gentle slope, extraordinary width, and abrupt lateral structural variations at the front of this belt. To understand the structures and the formation mechanism of the structural reentrants, remote sensing and seismic interpretation techniques are used to study the surface and subsurface geology. Geomorphic features are extracted from the Shuttle Radar Topography Mission (SRTM) DEM data. Structures are interpreted from Landsat ETM+ images and published maps. These data suggest that the varying resistance under the fold-and-thrust belt is the main cause of the distinct topographic and structural features. ASTER data are used to map the detailed lithology and structures in the Kalabagh Fault Zone, which is the largest lateral structure connecting the Salt Range and the Surghar Range at leading edge of the fold-and-thrust belt. Combining surface geology with seismic interpretations, cross sections are constructed to understand the fault geometry. Salt is found to have played an important role in the development of the Kalabagh Fault. InSAR observations are used to estimate the slip rate, and slip direction along the Kalalabagh Fault Zone. The deformation style interpreted from the interferogram is in concordance with the analogue modeling results. Integration of the geomorphologic analysis, structures, current deformation, and previous studies suggests that the foreland fold-and-thrust belt can be divided into three thrust wedges propagating on decollements with different rheological properties. The viscous salt decollement allows the Salt Range to propagate further southwards than the Surghar Range. The Kalabagh Fault accommodates different shortening between these wedges.

  14. Plankton Biomass Models Based on GIS and Remote Sensing Technique for Predicting Marine Megafauna Hotspots in the Solor Waters

    NASA Astrophysics Data System (ADS)

    Putra, MIH; Lewis, SA; Kurniasih, EM; Prabuning, D.; Faiqoh, E.

    2016-11-01

    Geographic information system and remote sensing techniques can be used to assist with distribution modelling; a useful tool that helps with strategic design and management plans for MPAs. This study built a pilot model of plankton biomass and distribution in the waters off Solor and Lembata, and is the first study to identify marine megafauna foraging areas in the region. Forty-three samples of zooplankton were collected every 4 km according to the range time and station of aqua MODIS. Generalized additive model (GAM) we used to modelling zooplankton biomass response from environmental properties.Thirty one samples were used to build a model of inverse distance weighting (IDW) (cell size 0.01°) and 12 samples were used as a control to verify the models accuracy. Furthermore, Getis-Ord Gi was used to identify the significance of the hotspot and cold-spot for foraging area. The GAM models was explain 88.1% response of zooplankton biomass and percent to full moon, phytopankton biomassbeing strong predictors. The sampling design was essential in order to build highly accurate models. Our models 96% accurate for phytoplankton and 88% accurate for zooplankton. The foraging behaviour was significantly related to plankton biomass hotspots, which were two times higher compared to plankton cold-spots. In addition, extremely steep slopes of the Lamakera strait support strong upwelling with highly productive waters that affect the presence of marine megafauna. This study detects that the Lamakera strait provides the planktonic requirements for marine megafauna foraging, helping to explain why this region supports such high diversity and abundance of marine megafauna.

  15. A novel approach to model exposure of coastal-marine ecosystems to riverine flood plumes based on remote sensing techniques.

    PubMed

    Álvarez-Romero, Jorge G; Devlin, Michelle; Teixeira da Silva, Eduardo; Petus, Caroline; Ban, Natalie C; Pressey, Robert L; Kool, Johnathan; Roberts, Jason J; Cerdeira-Estrada, Sergio; Wenger, Amelia S; Brodie, Jon

    2013-04-15

    Increased loads of land-based pollutants are a major threat to coastal-marine ecosystems. Identifying the affected marine areas and the scale of influence on ecosystems is critical to assess the impacts of degraded water quality and to inform planning for catchment management and marine conservation. Studies using remotely-sensed data have contributed to our understanding of the occurrence and influence of river plumes, and to our ability to assess exposure of marine ecosystems to land-based pollutants. However, refinement of plume modeling techniques is required to improve risk assessments. We developed a novel, complementary, approach to model exposure of coastal-marine ecosystems to land-based pollutants. We used supervised classification of MODIS-Aqua true-color satellite imagery to map the extent of plumes and to qualitatively assess the dispersal of pollutants in plumes. We used the Great Barrier Reef (GBR), the world's largest coral reef system, to test our approach. We combined frequency of plume occurrence with spatially distributed loads (based on a cost-distance function) to create maps of exposure to suspended sediment and dissolved inorganic nitrogen. We then compared annual exposure maps (2007-2011) to assess inter-annual variability in the exposure of coral reefs and seagrass beds to these pollutants. We found this method useful to map plumes and qualitatively assess exposure to land-based pollutants. We observed inter-annual variation in exposure of ecosystems to pollutants in the GBR, stressing the need to incorporate a temporal component into plume exposure/risk models. Our study contributes to our understanding of plume spatial-temporal dynamics of the GBR and offers a method that can also be applied to monitor exposure of coastal-marine ecosystems to plumes and explore their ecological influences.

  16. Cation exchange on the nanoscale: an emerging technique for new material synthesis, device fabrication, and chemical sensing.

    PubMed

    Rivest, Jessy B; Jain, Prashant K

    2013-01-07

    Cation exchange is an age-old technique for the chemical conversion of liquids or extended solids by place-exchanging the cations in an ionic material with a different set of cations. The technique is undergoing a major revival with the advent of high-quality nanocrystals: researchers are now able to overcome the limitations in bulk systems and fully exploit cation exchange for materials synthesis and discovery via rapid, low-temperature transformations in the solid state. In this tutorial review, we discuss cation exchange as a promising materials synthesis and discovery tool. Exchange on the nanoscale exhibits some unique attributes: rapid kinetics at room temperature (orders of magnitude faster than in the bulk) and the tuning of reactivity via control of nanocrystal size, shape, and surface faceting. These features make cation exchange a convenient tool for accessing nanocrystal compositions and morphologies for which conventional synthesis may not be established. A simple exchange reaction allows extension of nanochemistry to a larger part of the periodic table, beyond the typical gamut of II-VI, IV-VI, and III-V materials. Cation exchange transformations in nanocrystals can be topotactic and size- and shape-conserving, allowing nanocrystals synthesized by conventional methods to be used as templates for production of compositionally novel, multicomponent, or doped nanocrystals. Since phases and compositions resulting from an exchange reaction can be kinetically controlled, rather than governed by the phase diagram, nanocrystals of metastable and hitherto inaccessible compositions are attainable. Outside of materials synthesis, applications for cation exchange exist in water purification, chemical staining, and sensing. Since nanoscale cation exchange occurs rapidly at room temperature, it can be integrated with sensitive environments such as those in biological systems. Cation exchange is already allowing access to a variety of new materials and processes

  17. Fiber Loop Ringdown — a Time-Domain Sensing Technique for Multi-Function Fiber Optic Sensor Platforms: Current Status and Design Perspectives

    PubMed Central

    Wang, Chuji

    2009-01-01

    Fiber loop ringdown (FLRD) utilizes an inexpensive telecommunications light source, a photodiode, and a section of single-mode fiber to form a uniform fiber optic sensor platform for sensing various quantities, such as pressure, temperature, strain, refractive index, chemical species, biological cells, and small volume of fluids. In FLRD, optical losses of a light pulse in a fiber loop induced by changes in a quantity are measured by the light decay time constants. FLRD measures time to detect a quantity; thus, FLRD is referred to as a time-domain sensing technique. FLRD sensors have near real-time response, multi-pass enhanced high-sensitivity, and relatively low cost (i.e., without using an optical spectral analyzer). During the last eight years since the introduction of the original form of fiber ringdown spectroscopy, there has been increasing interest in the FLRD technique in fiber optic sensor developments, and new application potential is being explored. This paper first discusses the challenging issues in development of multi-function, fiber optic sensors or sensor networks using current fiber optic sensor sensing schemes, and then gives a review on current fiber optic sensor development using FLRD technique. Finally, design perspectives on new generation, multi-function, fiber optic sensor platforms using FLRD technique are particularly presented. PMID:22408471

  18. Fiber loop ringdown - a time-domain sensing technique for multi-function fiber optic sensor platforms: current status and design perspectives.

    PubMed

    Wang, Chuji

    2009-01-01

    Fiber loop ringdown (FLRD) utilizes an inexpensive telecommunications light source, a photodiode, and a section of single-mode fiber to form a uniform fiber optic sensor platform for sensing various quantities, such as pressure, temperature, strain, refractive index, chemical species, biological cells, and small volume of fluids. In FLRD, optical losses of a light pulse in a fiber loop induced by changes in a quantity are measured by the light decay time constants. FLRD measures time to detect a quantity; thus, FLRD is referred to as a time-domain sensing technique. FLRD sensors have near real-time response, multi-pass enhanced high-sensitivity, and relatively low cost (i.e., without using an optical spectral analyzer). During the last eight years since the introduction of the original form of fiber ringdown spectroscopy, there has been increasing interest in the FLRD technique in fiber optic sensor developments, and new application potential is being explored. This paper first discusses the challenging issues in development of multi-function, fiber optic sensors or sensor networks using current fiber optic sensor sensing schemes, and then gives a review on current fiber optic sensor development using FLRD technique. Finally, design perspectives on new generation, multi-function, fiber optic sensor platforms using FLRD technique are particularly presented.

  19. Differential Radiometers Using Fabry-Perot Interferometric Technique for Remote Sensing Determination of Various Atmospheric Trace Gases

    NASA Technical Reports Server (NTRS)

    Georgieva, E. M.; Heaps, W. S.; Wilson, E. L.

    2007-01-01

    New type of remote sensing instrument based upon the Fabry-Perot inte rferometric technique has been developed at NASA's Goddard Space Flight Center. Fabry-Perot interferometry (FPI) is a well known, powerful spectroscopic technique and one of its many applications is to be use d to measure greenhouse gases and also some harmful species in the at mosphere. With this technique, absorption of particular species is me asured and related to its concentration. A solid Fabry-Perot etalon is used as a frequency filter to restrict the measurement to particular absorption bands of the gas of interest. With adjusting the thicknes s of the etalon that separation (in frequency) of the transmitted fri nges can be made equal to the almost constant separation of the gas a bsorption lines. By adjusting the temperature of the etalon, which changes the index of refi-action of its material, the transmission fring es can be brought into nearly exact correspondence with absorption li nes of the particular species. With this alignment between absorption lines and fringes, changes in the amount of a species in the atmosph ere strongly affect the amount of light transmitted by the etalon and can be related to gas concentration. The instrument that we have dev eloped detects the absorption of various atmospheric trace gases in d irect or reflected sunlight. Our instrument employing Fabry-Perot interferometer makes use of two features to achieve high sensitivity. The first is high spectral resolution enabling one to match the width of an atmospheric absorption feature by the instrumental band pass. The second is high optical throughput enabled by using multiple spectral lines simultaneously. For any species that one wishes to measure, thi s first feature is available while the use of multiple spectral features can be employed only for species with suitable spectra and freedom from interfering species in the same wavelength region. We have deve loped an instrument for use as ground based

  20. Comparison of parallel acquisition techniques generalized autocalibrating partially parallel acquisitions (GRAPPA) and modified sensitivity encoding (mSENSE) in functional MRI (fMRI) at 3T.

    PubMed

    Preibisch, Christine; Wallenhorst, Tim; Heidemann, Robin; Zanella, Friedhelm E; Lanfermann, Heinrich

    2008-03-01

    To evaluate the parallel acquisition techniques, generalized autocalibrating partially parallel acquisitions (GRAPPA) and modified sensitivity encoding (mSENSE), and determine imaging parameters maximizing sensitivity toward functional activation at 3T. A total of eight imaging protocols with different parallel imaging techniques (GRAPPA and mSENSE) and reduction factors (R = 1, 2, 3) were compared at different matrix sizes (64 and 128) with respect to temporal noise characteristics, artifact behavior, and sensitivity toward functional activation. Echo planar imaging (EPI) with GRAPPA and a reduction factor of 2 revealed similar image quality and sensitivity than full k-space EPI. A higher incidence of artifacts and a marked sensitivity loss occurred at R = 3. Even though the same eight-channel head coil was used for signal detection in all experiments, GRAPPA generally showed more benign patterns of spatially-varying noise amplification, and mSENSE was also more susceptible to residual unfolding artifacts than GRAPPA. At 3T and a reduction factor of 2, parallel imaging can be used with only little penalty with regard to sensitivity. With our implementation and coil setup the performance of GRAPPA was clearly superior to mSENSE. Thus, it seems advisable to pay special attention to the employed parallel imaging method and its implementation.

  1. Streamlined environmental remediation characterization using remote sensing techniques: Case studies for the US Department of Energy, Oak Ridge Operations

    SciTech Connect

    Carden, D.M.; Smyre, J.L.; Evers, T.K.; King, A.L.

    1996-07-01

    This paper provides an overview of the DOE Oak Ridge Operations Remote Sensing Program and discusses how data from this program have assisted the environmental restoration program in streamlining site-characterization activities. Three case studies are described where remote sensing imagery has provided a more focused understanding of site problems with a resultant reduction in the need for costly and time-consuming, ground-based sampling approaches.

  2. The Changing Face of the of Former Soviet Cities: Elucidated by Remote Sensing and Machine Learning Techniques

    NASA Astrophysics Data System (ADS)

    Poghosyan, Armen

    2017-04-01

    Despite remote sensing of urbanization emerged as a powerful tool to acquire critical knowledge about urban growth and its effects on global environmental change, human-environment interface as well as environmentally sustainable urban development, there is lack of studies utilizing remote sensing techniques to investigate urbanization trends in the Post-Soviet states. The unique challenges accompanying the urbanization in the Post-Soviet republics combined with the expected robust urban growth in developing countries over the next several decades highlight the critical need for a quantitative assessment of the urban dynamics in the former Soviet states as they navigate towards a free market democracy. This study uses total of 32 Level-1 precision terrain corrected (L1T) Landsat scenes with 30-m resolution as well as further auxiliary population and economic data for ten cities distributed in nine former Soviet republics to quantify the urbanization patterns in the Post-Soviet region. Land cover in each urban center of this study was classified by using Support Vector Machine (SVM) learning algorithm with overall accuracies ranging from 87 % to 97 % for 29 classification maps over three time steps during the past twenty-five years in order to estimate quantities, trends and drivers of urban growth in the study area. The results demonstrated several spatial and temporal urbanization patterns observed across the Post-Soviet states and based on urban expansion rates the cities can be divided into two groups, fast growing and slow growing urban centers. The relatively fast-growing urban centers have an average urban expansion rate of about 2.8 % per year, whereas the slow growing cities have an average urban expansion rate of about 1.0 % per year. The total area of new land converted to urban environment ranged from as low as 26 km2 to as high as 780 km2 for the ten cities over the 1990 - 2015 period, while the overall urban land increase ranged from 11.3 % to 96

  3. Integration of remote sensing and ground-based techniques for the study of land degradation phenomena in coastal areas.

    NASA Astrophysics Data System (ADS)

    Imbrenda, Vito; Coluzzi, Rosa; Calamita, Giuseppe; Luigia Giannossi, Maria; D'Emilio, Mariagrazia; Lanfredi, Maria; Makris, John; Palombo, Angelo; Pascucci, Simone; Santini, Federico; Margiotta, Salvatore; Emanuela Bonomo, Agnese; De Martino, Gregory; Perrone, Angela; Rizzo, Enzo; Pignatti, Stefano; Summa, Vito; Simoniello, Tiziana

    2015-04-01

    Land degradation processes, such as salinization and waterlogging, are increasingly affecting extensive areas devoted to agriculture threatening the sustainability of farming practices. Soil salinization typically appears as an excess accumulation of salt generally pronounced at the soil surface. Commonly, soil salinity is defined and measured by means of laboratory measurements of the electrical conductivity of liquid extracted from saturated soil-paste or different soil-water suspensions. Lab measurements are generally time consuming, costly, destructive, untimely for practical situations where the determination of the causes and/or the assessment of management practices are of interest. Recently, emerging survey techniques proved to be powerful tools to support soil salinity appraisal reducing costs and increasing the amount of spatial information. In the frame of PRO-LAND project (PO-FESR Basilicata 2007-2013) the research activities have been focused on the study of a complex salinization phenomenon occurring in a coastal environment of the Basilicata region (Southern Italy) as a result of natural and anthropic disturbances. The study area is located in the southernmost part of the Bradanic Trough along the sandy Ionian coastal plain. The hydrogeological conditions affect shallowness of the aquifer (45-50 cm below the ground) allowing the occurrence of seawater intrusion. Moreover, during last century, human activities, i.e. built-up of dams, the emergence of farms and industries, played a relevant role in the alteration of soil and groundwater quality of the area. In this work, both ground-based and remote sensing data were used. First, a geophysical mapping of electrical conductivity was carried out using a multi-frequency portable electro-magnetic induction (EMI) sensor. Based on the geophysical mapping and on optimization sampling approach, a number of locations were identified to collect soil samples for the geomineralogical characterization. Airborne

  4. An in-place recalibration technique to extend the temperature capability of capacitance-sensing, rotor-blade-tip-clearance measurement systems

    NASA Technical Reports Server (NTRS)

    Barranger, J.

    1978-01-01

    It is known that capacitance-sensing, rotor-blade-tip-clearance measurement systems suffer from a strong dependency on probe tip temperature and humidity. A novel in-place recalibration technique partly overcomes this problem through a simple modification of the electronics that permits a scale factor correction. The technique is used to reduce the errors in a commercial system by more than 50 percent up to a temperature of 370 C (700 F). A probe design is proposed to further raise the maximum temperature capability of the measurement system.

  5. Sensing interrogation technique for fiber-optic interferometer type of sensors based on a single-passband RF filter.

    PubMed

    Chen, Hao; Zhang, Shiwei; Fu, Hongyan; Zhou, Bin; Chen, Nan

    2016-02-08

    In this paper, a sensing interrogation system for fiber-optic interferometer type of sensors by using a single-passband radio-frequency (RF) filter has been proposed and experimentally demonstrated. The fiber-optic interferometer based sensors can give continuous optical sampling, and along with dispersive medium a single-passband RF frequency response can be achieved. The sensing parameter variation on the fiber-optic interferometer type of sensors will affect their free spectrum range, and thus the peak frequency of the RF filter. By tracking the central frequency of the passband the sensing parameter can be demodulated. As a demonstration, in our experiment a fiber Mach-Zehnder interferometer (FMZI) based temperature sensor has been interrogated. By tracking the peak frequency of the passband the temperature variation can be monitored. In our experiment, the sensing responsivity of 10.5 MHz/°C, 20.0 MHz/°C and 41.2 MHz/°C, when the lengths of sensing fiber are 1 m, 2 m and 4 m have been achieved.

  6. An information system design for watershed-wide modeling of water loss to the atmosphere using remote sensing techniques

    NASA Technical Reports Server (NTRS)

    Khorram, S.

    1977-01-01

    Results are presented of a study intended to develop a general location-specific remote-sensing procedure for watershed-wide estimation of water loss to the atmosphere by evaporation and transpiration. The general approach involves a stepwise sequence of required information definition (input data), appropriate sample design, mathematical modeling, and evaluation of results. More specifically, the remote sensing-aided system developed to evaluate evapotranspiration employs a basic two-stage two-phase sample of three information resolution levels. Based on the discussed design, documentation, and feasibility analysis to yield timely, relatively accurate, and cost-effective evapotranspiration estimates on a watershed or subwatershed basis, work is now proceeding to implement this remote sensing-aided system.

  7. An information system design for watershed-wide modeling of water loss to the atmosphere using remote sensing techniques

    NASA Technical Reports Server (NTRS)

    Khorram, S.

    1977-01-01

    Results are presented of a study intended to develop a general location-specific remote-sensing procedure for watershed-wide estimation of water loss to the atmosphere by evaporation and transpiration. The general approach involves a stepwise sequence of required information definition (input data), appropriate sample design, mathematical modeling, and evaluation of results. More specifically, the remote sensing-aided system developed to evaluate evapotranspiration employs a basic two-stage two-phase sample of three information resolution levels. Based on the discussed design, documentation, and feasibility analysis to yield timely, relatively accurate, and cost-effective evapotranspiration estimates on a watershed or subwatershed basis, work is now proceeding to implement this remote sensing-aided system.

  8. Context predictor based sparse sensing technique and smart transmission architecture for IoT enabled remote health monitoring applications.

    PubMed

    Sai Kiran, M P R; Rajalakshmi, P; Acharyya, Amit

    2014-01-01

    In hyperconnectivity scenario, managing the amount of data acquired from sensors in the Body Area Networks (BANs) is one of the major issues. In this paper we propose an on-chip context predictor based sparse sensing technology with smart transmission architecture which makes use of confidence interval calculation from the features that present in the data, thereby achieving statistical guarantee. The proposed architecture uses intelligent sparse sensing, which eradicates the collection of redundant data, thereby reducing the amount of data generated. For the performance analysis, we considered ECG data acquisition and transmission system. The proposed architecture when applied on the data collected from 10 patients reduces the duty cycle of the sensing unit to 27.99%, by achieving an energy saving of 72% and the mean deviation of sampled data from the original data is 2%.

  9. Evaluation of water-use efficiency in foxtail millet (Setaria italica) using visible-near infrared and thermal spectral sensing techniques.

    PubMed

    Wang, Meng; Ellsworth, Patrick Z; Zhou, Jianfeng; Cousins, Asaph B; Sankaran, Sindhuja

    2016-05-15

    Water limitations decrease stomatal conductance (g(s)) and, in turn, photosynthetic rate (A(net)), resulting in decreased crop productivity. The current techniques for evaluating these physiological responses are limited to leaf-level measures acquired by measuring leaf-level gas exchange. In this regard, proximal sensing techniques can be a useful tool in studying plant biology as they can be used to acquire plant-level measures in a high-throughput manner. However, to confidently utilize the proximal sensing technique for high-throughput physiological monitoring, it is important to assess the relationship between plant physiological parameters and the sensor data. Therefore, in this study, the application of rapid sensing techniques based on thermal imaging and visual-near infrared spectroscopy for assessing water-use efficiency (WUE) in foxtail millet (Setaria italica (L.) P. Beauv) was evaluated. The visible-near infrared spectral reflectance (350-2500 nm) and thermal (7.5-14 µm) data were collected at regular intervals from well-watered and drought-stressed plants in combination with other leaf physiological parameters (transpiration rate-E, A(net), g(s), leaf carbon isotopic signature-δ(13)C(leaf), WUE). Partial least squares regression (PLSR) analysis was used to predict leaf physiological measures based on the spectral data. The PLSR modeling on the hyperspectral data yielded accurate and precise estimates of leaf E, gs, δ(13)C(leaf), and WUE with coefficient of determination in a range of 0.85-0.91. Additionally, significant differences in average leaf temperatures (~1°C) measured with a thermal camera were observed between well-watered plants and drought-stressed plants. In summary, the visible-near infrared reflectance data, and thermal images can be used as a potential rapid technique for evaluating plant physiological responses such as WUE. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Monitoring land-use change by combining participatory land-use maps with standard remote sensing techniques: Showcase from a remote forest catchment on Mindanao, Philippines

    NASA Astrophysics Data System (ADS)

    Mialhe, François; Gunnell, Yanni; Ignacio, J. Andres F.; Delbart, Nicolas; Ogania, Jenifer L.; Henry, Sabine

    2015-04-01

    This paper combines participatory activities (PA) with remote sensing analysis into an integrated methodology to describe and explain land-cover changes. A remote watershed on Mindanao (Philippines) is used to showcase the approach, which hypothesizes that the accuracy of expert knowledge gained from remote sensing techniques can be further enhanced by inputs from vernacular knowledge when attempting to understand complex land mosaics and past land-use changes. Six participatory sessions based on focus-group discussions were conducted. These were enhanced by community-based land-use mapping, resulting in a final total of 21 participatory land-use maps (PLUMs) co-produced by a sample of stakeholders with different sociocultural and ecological perspectives. In parallel, seven satellite images (Landsat MSS, Landsat TM, Landsat ETM+, and SPOT4) were classified following standard techniques and provided snapshots for the years 1976, 1996, and 2010. Local knowledge and collective memory contributed to define and qualify relevant land-use classes. This also provided information about what had caused the land-use changes in the past. Results show that combining PA with remote-sensing analysis provides a unique understanding of land-cover change because the two methods complement and validate one another. Substantive qualitative information regarding the chronology of land-cover change was obtained in a short amount of time across an area poorly covered by scientific literature. The remote sensing techniques contributed to test and to quantify verbal reports of land-use and land-cover change by stakeholders. We conclude that the method is particularly relevant to data-poor areas or conflict zones where rapid reconnaissance work is the only available option. It provides a preliminary but accurate baseline for capturing land changes and for reporting their causes and consequences. A discussion of the main challenges encountered (i.e. how to combine different systems of

  11. Optical techniques for sensing and measurement in hostile environments; Proceedings of the Meeting, Orlando, FL, May 21, 22, 1987

    NASA Astrophysics Data System (ADS)

    Gillespie, Calvin H.; Greenwell, Roger A.

    1987-01-01

    Papers are presented on referencing in fiber optic sensing systems, optical fiber chemical sensing networks, and the radiation response of new pure silica fibers. Also considered are a comparison of gamma, neutron, and proton irradiations of multimode fibers, a pinhole camera for hot environment viewing of electron beam materials processing, and the utilization of optical image data from the advanced test accelerator. Other topics include the application of an interferometer spectrometer aboard the Space Shuttle with a payload specialist in the control loop, hydrogen chloride measurements in launch-vehicle exhaust clouds, and a rocket-borne telescoped Fourier transform spectrometer operating at 10 K.

  12. Potential of a New Technique for Remote Sensing of Hydrocarbon Accumulations and Blind Uranium Deposits: Buried Lif Thermoluminescence Dosimeters

    NASA Technical Reports Server (NTRS)

    Siegel, F. R.; Vaz, J. E.; Lindholm, R. C.

    1982-01-01

    Buried thermoluminescence dosimeters may be useful in remote sensing of petroleum and natural gas accumulations and blind uranium deposits. They act as integrating detectors that smooth out the effects of environmental variations that affect other measuring systems and result in irregularities and poor repeatability in measurements made during gas and radiometric surveys.

  13. Sub-THz-range linearly chirped signals characterized using linear optical sampling technique to enable sub-millimeter resolution for optical sensing applications.

    PubMed

    Wang, Shuai; Fan, Xinyu; Wang, Bin; Yang, Guangyao; He, Zuyuan

    2017-05-01

    Pulse compression technique is a particularly competitive method that enables both high spatial resolution and dynamic range in coherent radar and distributed fiber sensing systems. Up to now, the frequency bandwidths of most pulse compression techniques are restricted to tens of GHz. In this paper, we propose an all-optic sub-THz-range linearly chirped optical source and a large-bandwidth detection system to characterize it. Taking advantage of the chromatic dispersion effect, ultrashort optical pulses are stretched to be ~10 ns linearly chirped pulses with sub-THz range, which yields a large time-bandwidth product of 4500, a high compression ratio of 4167 and a chirp rate of 45 GHz/ns. The generated waveform is characterized with high precision thanks to the large detection bandwidth of linear optical sampling technique. A spatial resolution of 120 μm and an extinction ratio of 20.4 dB is demonstrated by using this technique, which paves the way for ultra-high spatial resolution and long range sensing applications such as LIDAR and optical reflectometry.

  14. A Vision-Based Driver Nighttime Assistance and Surveillance System Based on Intelligent Image Sensing Techniques and a Heterogamous Dual-Core Embedded System Architecture

    PubMed Central

    Chen, Yen-Lin; Chiang, Hsin-Han; Chiang, Chuan-Yen; Liu, Chuan-Ming; Yuan, Shyan-Ming; Wang, Jenq-Haur

    2012-01-01

    This study proposes a vision-based intelligent nighttime driver assistance and surveillance system (VIDASS system) implemented by a set of embedded software components and modules, and integrates these modules to accomplish a component-based system framework on an embedded heterogamous dual-core platform. Therefore, this study develops and implements computer vision and sensing techniques of nighttime vehicle detection, collision warning determination, and traffic event recording. The proposed system processes the road-scene frames in front of the host car captured from CCD sensors mounted on the host vehicle. These vision-based sensing and processing technologies are integrated and implemented on an ARM-DSP heterogamous dual-core embedded platform. Peripheral devices, including image grabbing devices, communication modules, and other in-vehicle control devices, are also integrated to form an in-vehicle-embedded vision-based nighttime driver assistance and surveillance system. PMID:22736956

  15. A vision-based driver nighttime assistance and surveillance system based on intelligent image sensing techniques and a heterogamous dual-core embedded system architecture.

    PubMed

    Chen, Yen-Lin; Chiang, Hsin-Han; Chiang, Chuan-Yen; Liu, Chuan-Ming; Yuan, Shyan-Ming; Wang, Jenq-Haur

    2012-01-01

    This study proposes a vision-based intelligent nighttime driver assistance and surveillance system (VIDASS system) implemented by a set of embedded software components and modules, and integrates these modules to accomplish a component-based system framework on an embedded heterogamous dual-core platform. Therefore, this study develops and implements computer vision and sensing techniques of nighttime vehicle detection, collision warning determination, and traffic event recording. The proposed system processes the road-scene frames in front of the host car captured from CCD sensors mounted on the host vehicle. These vision-based sensing and processing technologies are integrated and implemented on an ARM-DSP heterogamous dual-core embedded platform. Peripheral devices, including image grabbing devices, communication modules, and other in-vehicle control devices, are also integrated to form an in-vehicle-embedded vision-based nighttime driver assistance and surveillance system.

  16. Remote sensing estimation of the total phosphorus concentration in a large lake using band combinations and regional multivariate statistical modeling techniques.

    PubMed

    Gao, Yongnian; Gao, Junfeng; Yin, Hongbin; Liu, Chuansheng; Xia, Ting; Wang, Jing; Huang, Qi

    2015-03-15

    Remote sensing has been widely used for ater quality monitoring, but most of these monitoring studies have only focused on a few water quality variables, such as chlorophyll-a, turbidity, and total suspended solids, which have typically been considered optically active variables. Remote sensing presents a challenge in estimating the phosphorus concentration in water. The total phosphorus (TP) in lakes has been estimated from remotely sensed observations, primarily using the simple individual band ratio or their natural logarithm and the statistical regression method based on the field TP data and the spectral reflectance. In this study, we investigated the possibility of establishing a spatial modeling scheme to estimate the TP concentration of a large lake from multi-spectral satellite imagery using band combinations and regional multivariate statistical modeling techniques, and we tested the applicability of the spatial modeling scheme. The results showed that HJ-1A CCD multi-spectral satellite imagery can be used to estimate the TP concentration in a lake. The correlation and regression analysis showed a highly significant positive relationship between the TP concentration and certain remotely sensed combination variables. The proposed modeling scheme had a higher accuracy for the TP concentration estimation in the large lake compared with the traditional individual band ratio method and the whole-lake scale regression-modeling scheme. The TP concentration values showed a clear spatial variability and were high in western Lake Chaohu and relatively low in eastern Lake Chaohu. The northernmost portion, the northeastern coastal zone and the southeastern portion of western Lake Chaohu had the highest TP concentrations, and the other regions had the lowest TP concentration values, except for the coastal zone of eastern Lake Chaohu. These results strongly suggested that the proposed modeling scheme, i.e., the band combinations and the regional multivariate

  17. An integrated study of earth resources in the state of California using remote sensing techniques. [water and forest management

    NASA Technical Reports Server (NTRS)

    Colwell, R. N.

    1974-01-01

    Progress and results of an integrated study of California's water resources are discussed. The investigation concerns itself primarily with the usefulness of remote sensing of relation to two categories of problems: (1) water supply; and (2) water demand. Also considered are its applicability to forest management and timber inventory. The cost effectiveness and utility of remote sensors such as the Earth Resources Technology Satellite for water and timber management are presented.

  18. Laboratory and Field Application of River Depth Estimation Techniques Using Remotely Sensed Data: Annual Report Year 1

    DTIC Science & Technology

    2013-09-30

    coral reefs and other coastal environments. Seventh International Conference on Remote Sensing for Marine and Coastal Environments, National Oceanic...solutions, the equations expressing conservation of mass and momentum were simplified based on a few reasonable assumptions to give expressions...component of the equation expressing conservation of momentum for river flow, if we assume the flow is incompressible and quasi-steady, has no lateral

  19. SU-C-213-04: Application of Depth Sensing and 3D-Printing Technique for Total Body Irradiation (TBI) Patient Measurement and Treatment Planning

    SciTech Connect

    Lee, M; Suh, T; Han, B; Xing, L; Jenkins, C

    2015-06-15

    Purpose: To develop and validate an innovative method of using depth sensing cameras and 3D printing techniques for Total Body Irradiation (TBI) treatment planning and compensator fabrication. Methods: A tablet with motion tracking cameras and integrated depth sensing was used to scan a RANDOTM phantom arranged in a TBI treatment booth to detect and store the 3D surface in a point cloud (PC) format. The accuracy of the detected surface was evaluated by comparison to extracted measurements from CT scan images. The thickness, source to surface distance and off-axis distance of the phantom at different body section was measured for TBI treatment planning. A 2D map containing a detailed compensator design was calculated to achieve uniform dose distribution throughout the phantom. The compensator was fabricated using a 3D printer, silicone molding and tungsten powder. In vivo dosimetry measurements were performed using optically stimulated luminescent detectors (OSLDs). Results: The whole scan of the anthropomorphic phantom took approximately 30 seconds. The mean error for thickness measurements at each section of phantom compare to CT was 0.44 ± 0.268 cm. These errors resulted in approximately 2% dose error calculation and 0.4 mm tungsten thickness deviation for the compensator design. The accuracy of 3D compensator printing was within 0.2 mm. In vivo measurements for an end-to-end test showed the overall dose difference was within 3%. Conclusion: Motion cameras and depth sensing techniques proved to be an accurate and efficient tool for TBI patient measurement and treatment planning. 3D printing technique improved the efficiency and accuracy of the compensator production and ensured a more accurate treatment delivery.

  20. Whole-heart cine MRI in a single breath-hold--a compressed sensing accelerated 3D acquisition technique for assessment of cardiac function.

    PubMed

    Wech, T; Pickl, W; Tran-Gia, J; Ritter, C; Beer, M; Hahn, D; Köstler, H

    2014-01-01

    The aim of this study was to perform functional MR imaging of the whole heart in a single breath-hold using an undersampled 3 D trajectory for data acquisition in combination with compressed sensing for image reconstruction. Measurements were performed using an SSFP sequence on a 3 T whole-body system equipped with a 32-channel body array coil. A 3 D radial stack-of-stars sampling scheme was utilized enabling efficient undersampling of the k-space and thereby accelerating data acquisition. Compressed sensing was applied for the reconstruction of the missing data. A validation study was performed based on a fully sampled dataset acquired by standard Cartesian cine imaging of 2 D slices on a healthy volunteer. The results were investigated with regard to systematic errors and resolution losses possibly introduced by the developed reconstruction. Subsequently, the proposed technique was applied for in-vivo functional cardiac imaging of the whole heart in a single breath-hold of 27  s. The developed technique was tested on three healthy volunteers to examine its reproducibility. By means of the results of the simulation (temporal resolution: 47  ms, spatial resolution: 1.4 × 1.4 × 8  mm, 3 D image matrix: 208 × 208 × 10), an overall acceleration factor of 10 has been found where the compressed sensing reconstructed image series shows only very low systematic errors and a slight in-plane resolution loss of 15 %. The results of the in-vivo study (temporal resolution: 40.5  ms, spatial resolution: 2.1 × 2.1 × 8  mm, 3 D image matrix: 224 × 224 × 12) performed with an acceleration factor of 10.7 confirm the overall good image quality of the presented technique for undersampled acquisitions. The combination of 3 D radial data acquisition and model-based compressed sensing reconstruction allows high acceleration factors enabling cardiac functional imaging of the whole heart within only one breath-hold. The

  1. Flood Prediction for the Tam Nong District in Mekong Delta Using Hydrological Modelling and Hydrologic Remote Sensing Technique

    NASA Astrophysics Data System (ADS)

    Kappas, Martin; Nguyen Hong, Quang; Thanh, Nga Pham Thi; Thu, Hang Le Thi; Nguyen Vu, Giang; Degener, Jan; Rafiei Emam, Ammar

    2017-04-01

    There has been an increasing attention to the large trans-boundary Mekong river basin due to various problems related to water management and flood control, for instance. Vietnam Mekong delta is located at the downstream of the river basin where is affected most by this human-induced reduction in flows from the upstream. On the other hand, the flood plain of nine anastomosing channels is increasingly effected by the seawater intrusion due to sea level rising of climate change. This results in negative impacts of salinization, drought, and floods, while formerly flooding had frequently brought positive natural gain of irrigation water and alluvial aggradation. In this research, our aim is to predict flooding for the better water management adaptation and control. We applied the model HEC-SSP 2.1 to analyze flood flow frequency, two-dimensional unsteady flow calculations in HEC-RAS 5.0 for simulating a floodplain inundation. Remote sensing-based water level (Jason-2) and inundation map were used for validation and comparison with the model simulations. The results revealed a reduction of water level at all the monitoring stations, particularly in the last decade. In addition, a trend of the inundation extension gradually declined, but in some periods it remained severe due to water release from upstream reservoirs during the rainy season (October-November). We found an acceptable agreement between the HEC-RAS and remote sensing flooding maps (around 70%). Based on the flood routine analysis, we could conclude that the water level will continue lower and lead to a trend of drought and salinization harsher in the near future. Keywords: Mekong delta, flood control, inundation, water management, hydrological modelling, remote sensing

  2. Assessing Natural Disaster Impacts and Recovery Using Multifrequency, Fully-Polarimetric Synthetic Aperture Radar (SAR) and Optical Remote Sensing Techniques

    NASA Astrophysics Data System (ADS)

    Weissel, J. K.; Czuchlewski, K. R.; Kim, Y.

    2002-12-01

    Many natural disasters involving landslides, volcanic eruptions, fires, or floods entail terrain resurfacing, followed by subsequent recovery. Modern satellite and airborne remote sensing technologies, which combine broad spatial coverage and high spatial resolution with time-sequential site revisit capability, can provide important information on the extent and duration of major landscape disturbance. In humid climate settings, these hazards temporarily remove or replace a natural vegetation cover and in doing so, modify the physical properties of the land surface. In optical remote sensing, removal of vegetation alters surface albedo in the visible -- near infrared (V-NIR) waveband, particularly the high reflectance from vegetation in the NIR. For SAR remote sensing, removal of vegetation cover causes a change in dominant microwave scattering mechanism for the areas affected. SAR has operational advantages over optical sensors for rapid disaster assessment because of its day/night acquisition capability, the ability to ``see through'' smoke, clouds and dust, and the side-looking viewing geometry, which is an advantage whenever data collection directly above the site would prove dangerous. We show how multifrequency, fully-polarimetric airborne SAR data can be ``inverted'' for parameters that reflect scattering mechanism signatures diagnostic of different surface cover types. We apply a uniform approach to map landslides resulting from the 1999 Mw 7.6 Chi-Chi earthquake in Taiwan, volcanic flows from the major 1996 eruption of Manam volcano in Papua New Guinea, and the extent of damage from the summer 2002 Rodeo -- Chediski wildfire in Arizona. In addition, earlier work has shown that multifrequency SAR polarimetric backscatter is sensitive to total above-ground biomass. This attribute can be exploited to calculate vegetation loss during a disaster and for assessment of regrowth during the recovery phase.

  3. Use of remote sensing techniques for geological hazard surveys in vegetated urban regions. [multispectral imagery for lithological mapping

    NASA Technical Reports Server (NTRS)

    Stow, S. H.; Price, R. C.; Hoehner, F.; Wielchowsky, C.

    1976-01-01

    The feasibility of using aerial photography for lithologic differentiation in a heavily vegetated region is investigated using multispectral imagery obtained from LANDSAT satellite and aircraft-borne photography. Delineating and mapping of localized vegetal zones can be accomplished by the use of remote sensing because a difference in morphology and physiology results in different natural reflectances or signatures. An investigation was made to show that these local plant zones are affected by altitude, topography, weathering, and gullying; but are controlled by lithology. Therefore, maps outlining local plant zones were used as a basis for lithologic map construction.

  4. Measuring urban sprawl on geospatial indices characterized by leap frog development using remote sensing and GIS techniques

    NASA Astrophysics Data System (ADS)

    Noor, N. M.; Asmawi, M. Z.; Rusni, N. A.

    2014-02-01

    Characterizing urban sprawl using spatial measures requires a concise definition of what constitutes sprawling urban spatial patterns. This research attempts to study a measurement of defining sprawl by using leapfrog development index through remote sensing and GIS approach. The IKONOS pan-sharpened and SPOT-5 with 1 and 2.5 meter resolution were used and combined with Geographical information system (GIS) database to analyze the geospatial indicators using the leapfrog development index. Kuantan city has been selected as a study area to examine the leapfrog development based on land use pattern for year 2012. The findings show Kuantan has identified as non-sprawling cities with result from characterization in leapfrog development that has been tested. However, the gap between sprawl and non-sprawling was very low. It is anticipated this research will provide a new direction in sprawl nationally that address finding of sprawl at the atomic level and present a robust analytical approach for characterizing urban development in city scale at once promoting a city via GIS & Remote Sensing technology respectively towards Digital and Green cities.

  5. Integration of conventional GIS-based techniques and remote sensing analysis to landslide risk assessment at basin scale

    NASA Astrophysics Data System (ADS)

    Agili, F.; Bartolomei, A.; Casagli, N.; Catani, F.; Ermini, L.; Farina, P.; Kukavicic, M.; Mirannalti, M.; Moretti, S.; Righini, G.

    2003-04-01

    This note concerns the preliminary results gathered in a research project aimed at landslide risk assessment in the Arno River basin (9000 km^2). The project, sponsored by the Basin Authority of the Arno River, started in the year 2002 and it will finish in the 2004. The objective of such a project consists of the updating of the landslide risk cartography related to the PAI document (Piano Assetto Idrogeologico) with reference to the Italian Law 267/1998. Different types of products will be generated: the updating of the existing inventory maps and the definition and application of a methodology for landslide hazard and risk mapping. Conventional methods, such as aerial-photo interpretation and field surveys are coupled with the use of different remote sensing methods, and all the data are integrated within a GIS environment. The analysis of remote sensing data regards both optical and radar images. In particular for the analysis of optical data, panchromatic and multispectral Landsat images are used in order to update the Corine standard land cover maps. In addition high resolution images (Ikonos and Quickbird), acquired in stereoscopic configuration, are analysed for integrating the aerial-photo intepretation. Differential SAR interferometry, implemented by using ERS and JERS data, is used in order to detect new mass movements, not yet observed and to evaluate the state of activity of known phenomena. Such data represent the base needed to produce the final landslide risk cartography.

  6. Comparative analysis of property taxation policies within Greece and Cyprus evaluating the use of GIS, CAMA, and remote sensing techniques

    NASA Astrophysics Data System (ADS)

    Dimopoulos, Thomas; Labropoulos, Tassos; Hadjimitsis, Diofantos G.

    2014-08-01

    This paper aims to examine how CAMA, GIS and Remote Sensing are integrated to assist property taxation. Real property tax apart from its fiscal dimension is directly linked to geographic location. The value of the land and other immovable features such as buildings and structures is determined from specific parameters. All these immovable assets are visible and have specific geographic location & coordinates, materials, occupied area, land-use & utility, ownership & occupancy status and finally a specific value (ad valorem property taxation system) according to which the property tax is levied to taxpayers. Of high importance in the tax imposing procedure is that the use of CAMA, GIS and Remote Sensing tools is capable of providing effective and efficient collection of this property value determining data. Furthermore, these tools can track changes during a property's lifecycle such parcel subdivision into plots, demolition of a building and development of a new one or track a change in the planning zone. The integration of these systems also supports a full range of business processes on revenue mobilization ranging from billing to taxpayers objections management.

  7. A turn-on fluorescence-sensing technique for glucose determination based on graphene oxide-DNA interaction.

    PubMed

    Zhang, Hao; Huang, Hui; Lin, Zihan; Su, Xingguang

    2014-11-01

    Graphene is a two-dimensional carbon nanomaterial one atom thick. Interactions between graphene oxide (GO) and ssDNA containing different numbers of bases have been proved to be remarkably different. In this paper we propose a novel approach for turn-on fluorescence sensing determination of glucose. Hydrogen peroxide (H2O2) is produced by glucose oxidase-catalysed oxidation of glucose. In the presence of ferrous iron (Fe(2+)) the hydroxyl radical (•OH) is generated from H2O2 by the Fenton reaction. This attacks FAM-labelled long ssDNA causing irreversible cleavage, as a result of the oxidative effect of •OH, producing an FAM-linked DNA fragment. Because of the weak interaction between GO and short FAM-linked DNA fragments, restoration of DNA fluorescence can be achieved by addition of glucose. Due to the excellent fluorescence quenching efficiency of GO and the specific catalysis of glucose oxidase, the sensitivity and selectivity of this method for GO-DNA sensing are extremely high. The linear range is from 0.5 to 10 μmol L(-1) and the detection limit for glucose is 0.1 μmol L(-1). The method has been successfully used for analysis of glucose in human serum.

  8. Spatial assessment of Geo-environmental data by the integration of Remote Sensing and GIS techniques for Sitakund Region, Eastern foldbelt, Bangladesh.

    NASA Astrophysics Data System (ADS)

    Gazi, M. Y.; Rahman, M.; Islam, M. A.; Kabir, S. M. M.

    2016-12-01

    Techniques of remote sensing and geographic information systems (GIS) have been applied for the analysis and interpretation of the Geo-environmental assessment to Sitakund area, located within the administrative boundaries of the Chittagong district, Bangladesh. Landsat ETM+ image with a ground resolution of 30-meter and Digital Elevation Model (DEM) has been adopted in this study in order to produce a set of thematic maps. The diversity of the terrain characteristics had a major role in the diversity of recipes and types of soils that are based on the geological structure, also helped to diversity in land cover and use in the region. The geological situation has affected on the general landscape of the study area. The problem of research lies in the possibility of the estimating the techniques of remote sensing and geographic information systems in the evaluation of the natural data for the study area spatially as well as determine the appropriate in grades for the appearance of the ground and in line with the reality of the region. Software for remote sensing and geographic information systems were adopted in the analysis, classification and interpretation of the prepared thematic maps in order to get to the building of the Geo-environmental assessment map of the study area. Low risk geo-environmental land mostly covered area of Quaternary deposits especially with area of slope wash deposits carried by streams. Medium and high risk geo-environmental land distributed with area of other formation with the study area, mostly the high risk shows area of folds and faults. The study has assessed the suitability of lands for agricultural purpose and settlements in less vulnerable areas within this region.

  9. Interexaminer, intraexaminer and test-retest reliability of clinical knee joint-position-sense measurements using an image-capture technique.

    PubMed

    Relph, Nicola; Herrington, Lee

    2015-05-20

    Knee joint-position sense (JPS) plays a critical role in controlled and stable joint movement. Poor ability to sense position of the knee can therefore increase risk of injury. There is no agreed consensus on JPS measurement techniques and a lack of reliability statistics on methods. To identify the most reliable knee JPS measurement technique using image capture. Interexaminer, intraexaminer, and test-retest reliability of knee JPS measurements. Biomechanics laboratory. 10 asymptomatic participants. None. Relative and absolute error scores of knee JPS in 3 conditions (sitting, prone, active) through 3 ranges of movement (10-30°, 30-60°, 60-90°), into 2 directions (flexion and extension) using both legs (dominant and nondominant) collected during 15 trials and repeated 7 d after the first data collection. Statistical analysis by intraclass correlations revealed excellent interexaminer reliability between researchers (.98) and intraexaminer reliability within 1 researcher (.96). Test-retest reliability was highest in the sitting condition from a starting angle of 0°, target angle through 60-90° of flexion, using the dominant leg and absolute-error-score variables (ICC = .92). However, it was noted smallest detectable differences were a high percentage of mean values for all measures. The most reliable JPS measurement for asymptomatic participants has been identified. Practitioners should use this protocol when collecting JPS data during prescreening sessions. However, generalizability of findings to a class/group of clients exhibiting knee pathologies should be done with caution.

  10. Assessing high altitude glacier thickness, volume and area changes using field, GIS and remote sensing techniques: the case of Nevado Coropuna (Peru)

    NASA Astrophysics Data System (ADS)

    Peduzzi, P.; Herold, C.; Silverio, W.

    2010-08-01

    Higher temperatures and changes in precipitation patterns have induced an acute decrease in Andean glaciers, thus leading to additional stress on water supply. To adapt to climate changes, local governments need information on the rate of glacier area and volume losses and on current ice thickness. Remote sensing analyses of Coropuna glacier (Peru) delineate an acute glaciated area decline between 1955 and 2008. We tested how volume changes can be estimated with remote sensing and GIS techniques using digital elevation models derived from both topographic maps and satellite images. Ice thickness was measured in 2004 using a Ground Penetrating Radar coupled with a Ground Positioning System during a field expedition. It provided profiles of ice thickness on different slopes, orientations and altitudes. These were used to model the current glacier volume using Geographical Information System and statistical multiple regression techniques. The results revealed a significant glacier volume loss; however the uncertainty is higher than the measured volume loss. We also provided an estimate of the remaining volume. The field study provided the scientific evidence needed by COPASA, a local Peruvian NGO, and GTZ, the German international cooperation agency, in order to alert local governments and communities and guide them in adopting new climate change adaptation policies.

  11. Single-end simultaneous temperature and strain sensing techniques based on Brillouin optical time domain reflectometry in few-mode fibers.

    PubMed

    Weng, Yi; Ip, Ezra; Pan, Zhongqi; Wang, Ting

    2015-04-06

    Recently there is a growing interest in developing few-mode fiber (FMF) based distributed sensors, which can attain higher spatial resolution and sensitivity compared with the conventional single-mode approaches. However, current techniques require two lightwaves injected into both ends of FMF, resulting in their complicated setup and high cost, which causes a big issue for geotechnical and petroleum applications. In this paper, we present a single-end FMF-based distributed sensing system that allows simultaneous temperature and strain measurement by Brillouin optical time-domain reflectometry (BOTDR) and heterodyne detection. Theoretical analysis and experimental assessment of multi-parameter discriminative measurement techniques applied to distributed FMF sensors are presented. Experimental results confirm that FM-BOTDR has similar performance with two-end methods such as FM-BOTDA, but with simpler setup and lower cost. The temperature-induced expansion strain (TIES) in response to different modes is discussed as well. Furthermore, we optimized the FMF design by exploiting modal profile and doping concentration, which indicates up to fivefold enhancement in measurement accuracy. This novel distributed FM-sensing system endows with good sensitivity characteristics and can prevent catastrophic failure in many applications.

  12. An analysis of the accuracy and cost-effectiveness of a cropland inventory utilizing remote sensing techniques

    NASA Technical Reports Server (NTRS)

    Jensen, J. R.; Tinney, L. R.; Estes, J. E.

    1975-01-01

    Cropland inventories utilizing high altitude and Landsat imagery were conducted in Kern County, California. It was found that in terms of the overall mean relative and absolute inventory accuracies, a Landsat multidate analysis yielded the most optimum results, i.e., 98% accuracy. The 1:125,000 CIR high altitude inventory is a serious alternative which can be very accurate (97% or more) if imagery is available for a specific study area. The operational remote sensing cropland inventories documented in this study are considered cost-effective. When compared to conventional survey costs of $62-66 per 10,000 acres, the Landsat and high-altitude inventories required only 3-5% of this amount, i.e., $1.97-2.98.

  13. Application of FBG sensing technique for monitoring and early warning system of high-speed railway track conditions

    NASA Astrophysics Data System (ADS)

    Zhang, Yongjia; Liu, Fang; Jing, Yuhai; Li, Weilai

    2017-04-01

    High-speed railway has achieved remarkable development in China, and safety monitoring of high-speed railway is becoming an important research. Fiber bragg grating (FBG) sensing technology is applied for monitoring and early warning system of high-speed railway track condition in this paper. The sensor network is built by putting FBG sensors on the high-speed rail tracks, which is necessary for real-time online monitoring of railway track temperature, displacement and strain. These different variables are collected, processed and analyzed by FBG demodulator. In addition, the railway track temperature prediction model are established based on relevance vector regression algorithm, which further improves the prediction accuracy and generalization performance. The system has been applied in the realtime online monitoring and early warning system of Guangzhou-Shenzhen-Hong Kong high-speed railway track condition. The system is running in good condition and playing an important role in early warning.

  14. Biophotonic endoscopy: a review of clinical research techniques for optical imaging and sensing of early gastrointestinal cancer

    PubMed Central

    Coda, Sergio; Siersema, Peter D.; Stamp, Gordon W. H.; Thillainayagam, Andrew V.

    2015-01-01

    Detection, characterization, and staging constitute the fundamental elements in the endoscopic diagnosis of gastrointestinal diseases, but histology still remains the diagnostic gold standard. New developments in endoscopic techniques may challenge histopathology in the near future. An ideal endoscopic technique should combine a wide-field, “red flag” screening technique with an optical contrast or microscopy method for characterization and staging, all simultaneously available during the procedure. In theory, biophotonic advances have the potential to unite these elements to allow in vivo “optical biopsy.” These techniques may ultimately offer the potential to increase the rates of detection of high risk lesions and the ability to target biopsies and resections, and so reduce the need for biopsy, costs, and uncertainty for patients. However, their utility and sensitivity in clinical practice must be evaluated against those of conventional histopathology. This review describes some of the most recent applications of biophotonics in endoscopic optical imaging and metrology, along with their fundamental principles and the clinical experience that has been acquired in their deployment as tools for the endoscopist. Particular emphasis has been placed on translational label-free optical techniques, such as fluorescence spectroscopy, fluorescence lifetime imaging microscopy (FLIM), two-photon and multi-photon microscopy, second harmonic generation (SHG) and third harmonic generation (THG) imaging, optical coherence tomography (OCT), diffuse reflectance, Raman spectroscopy, and molecular imaging. PMID:26528489

  15. Integrating Remote Sensing Data with Directional Two-Dimensional Wavelet Analysis and Open Geospatial Techniques for Efficient Disaster Monitoring and Management

    PubMed Central

    Lin, Yun-Bin; Lin, Yu-Pin; Deng, Dong-Po; Chen, Kuan-Wei

    2008-01-01

    In Taiwan, earthquakes have long been recognized as a major cause of landslides that are wide spread by floods brought by typhoons followed. Distinguishing between landslide spatial patterns in different disturbance regimes is fundamental for disaster monitoring, management, and land-cover restoration. To circumscribe landslides, this study adopts the normalized difference vegetation index (NDVI), which can be determined by simply applying mathematical operations of near-infrared and visible-red spectral data immediately after remotely sensed data is acquired. In real-time disaster monitoring, the NDVI is more effective than using land-cover classifications generated from remotely sensed data as land-cover classification tasks are extremely time consuming. Directional two-dimensional (2D) wavelet analysis has an advantage over traditional spectrum analysis in that it determines localized variations along a specific direction when identifying dominant modes of change, and where those modes are located in multi-temporal remotely sensed images. Open geospatial techniques comprise a series of solutions developed based on Open Geospatial Consortium specifications that can be applied to encode data for interoperability and develop an open geospatial service for sharing data. This study presents a novel approach and framework that uses directional 2D wavelet analysis of real-time NDVI images to effectively identify landslide patterns and share resulting patterns via open geospatial techniques. As a case study, this study analyzed NDVI images derived from SPOT HRV images before and after the ChiChi earthquake (7.3 on the Richter scale) that hit the Chenyulan basin in Taiwan, as well as images after two large typhoons (xangsane and Toraji) to delineate the spatial patterns of landslides caused by major disturbances. Disturbed spatial patterns of landslides that followed these events were successfully delineated using 2D wavelet analysis, and results of pattern recognitions

  16. A comparison of cover calculation techniques for relating point-intercept vegetation sampling to remote sensing imagery

    USDA-ARS?s Scientific Manuscript database

    Accurate and timely spatial predictions of vegetation cover from remote imagery are an important data source for natural resource management. High-quality in situ data are needed to develop and validate these products. Point-intercept sampling techniques are a common method for obtaining quantitativ...

  17. Notes for the improvement of a remote sensing multispectral data non-supervised classification and mapping technique

    NASA Technical Reports Server (NTRS)

    Dalton, C. C.

    1973-01-01

    Examined are: (1) the sequential clustering technique for the unsupervised automatic classification and mapping of earth resources satellite data, (2) theoretical analysis of the tests which were used, and (3) derivation of an alternative set of tests and their necessary algorithm.

  18. A novel, double intra-carotid cannulation technique to study the effect of central nutrient sensing on glucose metabolism in the rat.

    PubMed

    Rijnsburger, M; Eggels, L; Castel, J; Cruciani-Guglielmacci, C; Ackermans, M T; Luquet, S; la Fleur, S E

    2017-10-01

    The hypothalamus plays a key role in central nutrient sensing and glucose homeostasis. Due to its position next to the third ventricle, intracerebroventricular (ICV) injections or osmotic minipumps are widely applied techniques in studying effects of hormones and other molecules on the hypothalamus and glucose metabolism. The intracarotid catheter technique in which a catheter is placed in the carotid artery, pointing towards the brain, provides a physiological route to centrally infuse blood-borne molecules in an undisturbed animal. To measure effects of central interventions on peripheral glucose metabolism, endogenous glucose production (EGP) and insulin sensitivity can be measured using a stable isotope technique. To combine both techniques, it is necessary to combine different catheters. We here describe a novel cannulation technique for the carotid artery, enabling stress-free infusions towards the brain and blood sampling from the carotid artery concomitantly, and infuse a stable isotope via the jugular vein. We showed accurate EGP measurements when intracarotically infusing saline towards the brain. The stress-hormone corticosterone, as well as energy expenditure, did not alter upon central infusion. ICV infusions bypass the blood-brain-barrier (BBB) and are thus a less physiological approach when studying central effects of blood-borne factors. Furthermore, ICV injections can elicit a stress response which can interfere with outcomes of glucose metabolism. We described a stress-free, physiological method to study effects of central infusions on peripheral parameters. This technique provides new opportunities for studying central effects of, for instance, hormones and nutrients, on glucose metabolism. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. A noble technique a using force-sensing resistor for immobilization-device quality assurance: A feasibility study

    NASA Astrophysics Data System (ADS)

    Cho, Min-Seok; Kim, Tae-Ho; Kang, Seong-Hee; Kim, Dong-Su; Kim, Kyeong-Hyeon; Shin, Dong-Seok; Noh, Yu-Yun; Koo, Hyun-Jae; Cheon, Geum Seong; Suh, Tae Suk; Kim, Siyong

    2016-03-01

    Many studies have reported that a patient can move even when an immobilization device is used. Researchers have developed an immobilization-device quality-assurance (QA) system that evaluates the validity of immobilization devices. The QA system consists of force-sensing-resistor (FSR) sensor units, an electric circuit, a signal conditioning device, and a control personal computer (PC) with in-house software. The QA system is designed to measure the force between an immobilization device and a patient's skin by using the FSR sensor unit. This preliminary study aimed to evaluate the feasibility of using the QA system in radiation-exposure situations. When the FSR sensor unit was irradiated with a computed tomography (CT) beam and a treatment beam from a linear accelerator (LINAC), the stability of the output signal, the image artifact on the CT image, and changing the variation on the patient's dose were tested. The results of this study demonstrate that this system is promising in that it performed within the error range (signal variation on CT beam < 0.30 kPa, root-mean-square error (RMSE) of the two CT images according to presence or absence of the FSR sensor unit < 15 HU, signal variation on the treatment beam < 0.15 kPa, and dose difference between the presence and the absence of the FSR sensor unit < 0.02%). Based on the obtained results, we will volunteer tests to investigate the clinical feasibility of the QA system.

  20. Non-contact online thickness measurement system for metal films based on eddy current sensing with distance tracking technique.

    PubMed

    Li, Wei; Wang, Hongbo; Feng, Zhihua

    2016-04-01

    This paper proposes an online, non-contact metal film thickness measurement system based on eddy current sensing. The slope of the lift-off curve (LOC) is used for characterizing target thickness. Theoretical derivation was conducted to prove that the slope is independent of the lift-off variation. In practice, the measurement has some immunity to the lift-off, but not perfect. The slope of LOC is still affected at some extent by the lift-off. Hence, a height tracking system was also proposed, which could stabilize the distance between the sensor and the target and significantly reduce the lift-off effect. The height tracking system contains a specially designed probe, which could vibrate rapidly to obtain a fast measurement speed, and its height can be adjusted up and down continuously to stabilize the lift-off. The sensor coil in the thickness measurement system was also used as the height sensor in the height tracking system. Several experiments were conducted to test the system performances under static and dynamic conditions. This measurement system demonstrated significant advantages, such as simple and clear conversion between the slope of LOC and target thickness, high resolution and stability, and minimized effect of lift-off variation.

  1. Use of remote sensing techniques for mitigation and relief action of the main disaster concerns in Syria

    NASA Astrophysics Data System (ADS)

    Dalati, M.

    The main disaster concern in Syria is the Earthquakes since that Northwest of Syria is part of one of the very active deformation belt on the Earth today This area and the western part of Syria are located along the great rift Afro-Arabian rift System Those areas are tectonically active and cause time to time a lot of seismically events This faulting zone system represent a unique structural feature in the Mediterranean Region The system formed initially as a result of the break up of the Arabian plate from the African plate since the mid-Cenozoic The other disaster concern in Syria is Landslides whom caused significant damaging in Syria during the last decades especially in the Northwestern and Southwestern regions Landslide disasters killed some people and destroyed many mud and cement houses coastal mountains and cut off some roads few years ago It is known that many of the earthquakes and landslides that ever happened on our planet are located in active faults zones So it is of most important to obtain detailed information on regional tectonic structures The main approach of active faults survey at present is to use geological and geophysical methods such as in-situ measuring drilling and analysis of gravity and magnetic fields However because of the magnitude of the work there are still many uncertainties that we cannot figure out by traditional approaches Remote sensing has been brought forward for many years and has applications in many hazard

  2. Application of GIS and Remote Sensing Techniques in Multitemporal Analyses of Soil Properties in the Foreland of the Carpathians

    NASA Astrophysics Data System (ADS)

    Glowienka, Ewa; Michalowska, Krystyna; Pekala, Agnieszka; Hejmanowska, Beata

    2016-10-01

    The paper presents a spatial and temporal analysis of the distribution of the soil salinity and its pH level of south-east Poland depending on selected environmental factors. The area under examination (Carpathian Foredeep, Carpathians flysch) is distinguished by its specific hydrological and geological conditions (the Vistula and the San valley). The research works were performed in relation to parameters that had been measured in-situ in 1995, 2000, 2005, and 2010. Using specialist GIS software, proper interpolation procedures were performed, which enabled visualization in the form of raster and vector maps for the spatial distribution of the examined soil properties. Moreover, an analysis of remote sensing data was completed. Based on the analysis, it was discovered that the biggest changes in all examined soil parameters took place in 2010 - changes in the soil salinity and its pH level, as well as in the content of potassium (K) and sodium (Na). Those changes occurred mainly in the north and south parts of the examined area. The underlying reason for those changes might have been the flood, which hit the region in June 2010.

  3. Ethanol sensing of V2O5 thin film prepared by spray pyrolysis technique: Effect of substrate to nozzle distance

    NASA Astrophysics Data System (ADS)

    Immanuel, P.; Prakash, A. Arockia; Mohan, C. Raja

    2017-05-01

    In the present investigation V2O5 thin films were prepared by spray pyrolysis by varying substrate to nozzle distance (SND) from 20 to 35 cm in steps of 5 cm. The structural studies by XRD results indicates that the crystallinity increases with increase in SND along (101), (201) orientation and for the film prepared at 30 cm gives a good crystallinity. The SEM image shows that the change in morphology, which strongly depends on the SND. Above 30 cm it slightly affects the surface morphology of the V2O5 thinfilm due to agglomeration. The presence of elemental constituents is confirmed from EDAX analysis. The band gap of the film prepared at 30 cm has a lowest value of 2.1 eV. The electrical studies like I-V, Hall Effect measurement and the conductivity is maximum for the film prepared at 30 cm. The ethanol sensing of the prepared film has been studied using Keithley source meter and the detailed results are presented and discussed.

  4. Characterization of sediments in the Clinch River, Tennessee, using remote sensing and multi-dimensional GIS techniques

    SciTech Connect

    Levine, D.A.; Hargrove, W.W.; Hoffman, F.

    1995-12-31

    Remotely-sensed hydro-acoustic data were used as input to spatial extrapolation tools in a GIS to develop two- and three-dimensional models of sediment densities in the Clinch River arm of Watts Bar Reservoir, Tennessee. This work delineated sediment deposition zones to streamline sediment sampling and to provide a tool for estimating sediment volumes and extrapolating contaminant concentrations throughout the system. The Clinch River arm of Watts Bar Reservoir has been accumulating sediment-bound contaminants from three Department of Energy (DOE) facilities on the Oak Ridge Reservation, Tennessee. Public concern regarding human and ecological health resulted in Watts Bar Reservoir being placed on the National Priorities List for SUPERFUND. As a result, DOE initiated and is funding the Clinch River Environmental Restoration Program (CR-ERP) to perform a remedial investigation to determine the nature and extent of sediment contamination in the Watts Bar Reservoir and the Clinch River and to quantify any human or ecological health risks. The first step in characterizing Clinch River sediments was to determine the locations of deposition zones. It was also important to know the sediment type distribution within deposition zones because most sediment-bound contaminants are preferentially associated to fine particles. A dual-frequency hydro-acoustic survey was performed to determine: (1) depth to the sediment water interface, (2) depth of the sediment layer, and (3) sediment characteristics (density) with depth (approximately 0.5-foot intervals). An array of geophysical instruments was used to meet the objectives of this investigation.

  5. Biological pH sensing based on the environmentally friendly Raman technique through a polyaniline probe.

    PubMed

    Li, Songyang; Liu, Zhiming; Su, Chengkang; Chen, Haolin; Fei, Xixi; Guo, Zhouyi

    2017-02-01

    The biological pH plays an important role in various cellular processes. In this work, a novel strategy is reported for biological pH sensing by using Raman spectroscopy and polyaniline nanoparticles (PANI NPs) as the pH-sensitive Raman probe. It is found that the Raman spectrum of PANI NPs is strongly dependent on the pH value. The intensities of Raman spectral bands at 1225 and 1454 cm(-1) increase obviously with pH value varying from 5.5 to 8.0, which covers the range of regular biological pH variation. The pH-dependent Raman performance of PANI NPs, as well as their robust Raman signals and sensitivities to pH, was well retained after the nanoparticles incorporated into living 4T1 breast adenocarcinoma cells. The data indicate that such PANI NPs can be used as an effective biological pH sensor. Most interestingly, the PANI spherical nanostructures can be acquired by a low-cost, metal-free, and one-pot oxidative polymerization, which gives them excellent biocompatibility for further biological applications.

  6. Application of remote sensing techniques in land-use planning: Flood-plain delineation. [Cochise County, Arizona

    NASA Technical Reports Server (NTRS)

    Altenstadter, J. (Principal Investigator); Clark, R. B.

    1974-01-01

    The delineation of areas subject to inundation by means of remotely-sensed data acquisition represents a considerable saving in personnel time. Repeated input from aerial sensor sources provides the planner with a potent tool for the formation of a data base and for the monitoring of land use patterns over a period of time. The primary output of this project was a set of base map overlays at a scale of 1:62,500 delineating areas which require special regulations when proposed for land use involving human habitation or certain classes of storage. A secondary product of the study was county-wide maps of watershed configurations and of soil hydrologic groups. Further research is anticipated to extend the mapping of watershed areas outside the political boundaries of Cochise County, which will provide data for subsequent rainfall-runoff relationship studies in the area. All of the data provided will be incorporated into the Cochise County composite computer mapping project now operational. Results of this project have improved the pool of information available to the planning staff of Cochise County.

  7. Optical methods for quantitative and label-free sensing in living human tissues: principles, techniques, and applications.

    PubMed

    Wilson, Robert H; Vishwanath, Karthik; Mycek, Mary-Ann

    2016-01-01

    We present an overview of quantitative and label-free optical methods used to characterize living biological tissues, with an emphasis on emerging applications in clinical tissue diagnostics. Specifically, this review focuses on diffuse optical spectroscopy, imaging, and tomography, optical coherence-based techniques, and non-linear optical methods for molecular imaging. The potential for non- or minimally-invasive assessment, quantitative diagnostics, and continuous monitoring enabled by these tissue-optics technologies provides significant promise for continued clinical translation.

  8. Comparison of the resulting error in data fusion techniques when used with remote sensing, earth observation, and in-situ data sets for water quality applications

    NASA Astrophysics Data System (ADS)

    Ziemba, Alexander; El Serafy, Ghada

    2016-04-01

    Ecological modeling and water quality investigations are complex processes which can require a high level of parameterization and a multitude of varying data sets in order to properly execute the model in question. Since models are generally complex, their calibration and validation can benefit from the application of data and information fusion techniques. The data applied to ecological models comes from a wide range of sources such as remote sensing, earth observation, and in-situ measurements, resulting in a high variability in the temporal and spatial resolution of the various data sets available to water quality investigators. It is proposed that effective fusion into a comprehensive singular set will provide a more complete and robust data resource with which models can be calibrated, validated, and driven by. Each individual product contains a unique valuation of error resulting from the method of measurement and application of pre-processing techniques. The uncertainty and error is further compounded when the data being fused is of varying temporal and spatial resolution. In order to have a reliable fusion based model and data set, the uncertainty of the results and confidence interval of the data being reported must be effectively communicated to those who would utilize the data product or model outputs in a decision making process[2]. Here we review an array of data fusion techniques applied to various remote sensing, earth observation, and in-situ data sets whose domains' are varied in spatial and temporal resolution. The data sets examined are combined in a manner so that the various classifications, complementary, redundant, and cooperative, of data are all assessed to determine classification's impact on the propagation and compounding of error. In order to assess the error of the fused data products, a comparison is conducted with data sets containing a known confidence interval and quality rating. We conclude with a quantification of the performance

  9. Application of infrared and UV-visible remote sensing techniques for studying the stratosphere and for estimating anthrophogenic emissions

    NASA Astrophysics Data System (ADS)

    Mellqvist, Johan Magnus

    1999-11-01

    Infrared and UV/visible broadband absorption techniques have been used in three applications related to environmental research and atmospheric science. The techniques are based on measuring the attenuation of light by the atmosphere in the infrared and UV/visible region, and since a very large number of species absorb light in these wavelength regions, the techniques studied allow the measurement of several species simultaneously. Measurements of high resolution infrared solar spectra have been conducted during 1995 to 1998 at an observatory in Norway (60.2oN, 10.75oE). From the solar spectra, atmospheric columns of O/sb 3 and the most abundant nitrogen, chlorine and fluorine species in the stratosphere have been retrieved, such as: HCl, ClONO/sb 2, ClO, HNO/sb 3, N/sb 2O, HF and COF/sb 2. In addition, height concentration profiles of HCl, O/sb 3, HF, N/sb 2O and CH/sb 4 have been retrieved from the spectra. These were compared to several other techniques, indicating uncertainties of 10-20% at 20 km decreasing both upwards and downwards in altitude. Chlorine activation, i.e. conversion of the reservoir species HCl and ClONO/sb 2 to ClO on ice particles in the stratosphere, could be quantified on several occasions during the measurement period. The measurements also indicated significant ozone depletion in the Arctic polar stratosphere of 1995. In the second application a new method for quantitative estimation of fugitive emissions of hydrocarbons from petrochemical industries has been developed. Tracer gases are released on the location of the leakages, and then concentration measurements are conducted downwind, over a long atmospheric path, by infrared absorption technique. What is unique with the method is a new approach based on the correlation of the tracer and the source gas concentrations over time. The method has been used to measure diffuse emissions of ethylene and propylene at several industrial sites during 1994 to 1998. Sensitivity experiments and

  10. Natural and environmental vulnerability analysis through remote sensing and GIS techniques: a case study of Indigirka River basin, Eastern Siberia, Russia

    NASA Astrophysics Data System (ADS)

    Boori, Mukesh S.; Choudhary, Komal; Kupriyanov, Alexander; Sugimoto, Atsuko; Evers, Mariele

    2016-10-01

    The aim of this research work is to understand natural and environmental vulnerability situation and its cause such as intensity, distribution and socio-economic effect in the Indigirka River basin, Eastern Siberia, Russia. This paper identifies, assess and classify natural and environmental vulnerability using landscape pattern from multidisciplinary approach, based on remote sensing and Geographical Information System (GIS) techniques. A model was developed by following thematic layers: land use/cover, vegetation, wetland, geology, geomorphology and soil in ArcGIS 10.2 software. According to numerical results vulnerability classified into five levels: low, sensible, moderate, high and extreme vulnerability by mean of cluster principal. Results are shows that in natural vulnerability maximum area covered by moderate (29.84%) and sensible (38.61%) vulnerability and environmental vulnerability concentrated by moderate (49.30%) vulnerability. So study area has at medial level vulnerability. The results found that the methodology applied was effective enough in the understanding of the current conservation circumstances of the river basin in relation to their environment with the help of remote sensing and GIS. This study is helpful for decision making for eco-environmental recovering and rebuilding as well as predicting the future development.

  11. High Resolution Stratigraphic Mapping in Complex Terrain: A Comparison of Traditional Remote Sensing Techniques with Unmanned Aerial Vehicle - Structure from Motion Photogrammetry

    NASA Astrophysics Data System (ADS)

    Nesbit, P. R.; Hugenholtz, C.; Durkin, P.; Hubbard, S. M.; Kucharczyk, M.; Barchyn, T.

    2016-12-01

    Remote sensing and digital mapping have started to revolutionize geologic mapping in recent years as a result of their realized potential to provide high resolution 3D models of outcrops to assist with interpretation, visualization, and obtaining accurate measurements of inaccessible areas. However, in stratigraphic mapping applications in complex terrain, it is difficult to acquire information with sufficient detail at a wide spatial coverage with conventional techniques. We demonstrate the potential of a UAV and Structure from Motion (SfM) photogrammetric approach for improving 3D stratigraphic mapping applications within a complex badland topography. Our case study is performed in Dinosaur Provincial Park (Alberta, Canada), mapping late Cretaceous fluvial meander belt deposits of the Dinosaur Park formation amidst a succession of steeply sloping hills and abundant drainages - creating a challenge for stratigraphic mapping. The UAV-SfM dataset (2 cm spatial resolution) is compared directly with a combined satellite and aerial LiDAR dataset (30 cm spatial resolution) to reveal advantages and limitations of each dataset before presenting a unique workflow that utilizes the dense point cloud from the UAV-SfM dataset for analysis. The UAV-SfM dense point cloud minimizes distortion, preserves 3D structure, and records an RGB attribute - adding potential value in future studies. The proposed UAV-SfM workflow allows for high spatial resolution remote sensing of stratigraphy in complex topographic environments. This extended capability can add value to field observations and has the potential to be integrated with subsurface petroleum models.

  12. Tools and Techniques to Collaborate and Connect with At-Risk Climate Communities UsingSensors, Remote Sensing Data, and Media

    NASA Astrophysics Data System (ADS)

    Drapkin, J. K.; Ramamurthy, P.; Vant-Hull, B.; Yuen, K.; Glenn, A.; Jusino, C.; Corbin, C.; Schuerman, M.; Keefe, J.; Brooke, H.

    2016-12-01

    Those most at risk during heat waves and floods are often the socio-economically vulnerable. Yet very few studies exist of indoor temperatures during heat waves or of standing water events at the neighborhood level during extreme events. ISeeChange, a community weather and climate journal, is developing tools and testing techniques in a series