A technique is described here in which the polarization properties of elastically scattered light and the unpolarized nature of excited fluorescence are utilized to extract white light induced chlorophyll fluorescence component from the... more
A technique is described here in which the polarization properties of elastically scattered light and the unpolarized nature of excited fluorescence are utilized to extract white light induced chlorophyll fluorescence component from the reflectance spectra of sea water. This technique was tested and shown to be effective for retrieval of the chlorophyll fluorescence in the 685 nm regions from reflectance
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Fluorescence Line Height (FLH) algorithms which estimate magnitude of chlorophyll fluorescence in reflectance (or water leaving radiance) spectra are based on the measurements of reflectance at three wavelengths in the fluorescence... more
Fluorescence Line Height (FLH) algorithms which estimate magnitude of chlorophyll fluorescence in reflectance (or water leaving radiance) spectra are based on the measurements of reflectance at three wavelengths in the fluorescence spectral zone. They are effective for the fluorescence retrieval in case 1 waters where chlorophyll concentration (Chl) is relatively low, (Chl) is a main driver of water optical properties
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Karenia brevis (K. brevis) blooms regularly in the Gulf of Mexico. However, detection from space still remains a challenge using standard bio-optical retrieval algorithms because of the uncertainties of atmospheric correction and spectral... more
Karenia brevis (K. brevis) blooms regularly in the Gulf of Mexico. However, detection from space still remains a challenge using standard bio-optical retrieval algorithms because of the uncertainties of atmospheric correction and spectral interferences arising in optically complex coastal waters from high concentrations of organic and inorganic materials. We propose a simple red band difference (RBD) technique to detect blooms,
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Page 1. Modeling of the fluorescence retrieval from reflectance spectra using polarization discrimination Alexander Gilerson, Jing Zhou, Barry M. Gross, Fred Moshary and Samir Ahmed NOAA-CREST/ The City College ofthe City University ofNew... more
Page 1. Modeling of the fluorescence retrieval from reflectance spectra using polarization discrimination Alexander Gilerson, Jing Zhou, Barry M. Gross, Fred Moshary and Samir Ahmed NOAA-CREST/ The City College ofthe City University ofNew York, New York, NY, 10031 ...
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... [7] OMG. Specification. A UML Profile for MARTE, Beta 1, 2007. [8] G. Ortiz, J. Hernández, P. Clemente, and P. Amaya. ... [13] J. Stankovic, R. Zhu, R. Poornalingam, C. Lu, Z. Yu, M. Humphrey, and B. Ellis. Vest: An aspect-based... more
... [7] OMG. Specification. A UML Profile for MARTE, Beta 1, 2007. [8] G. Ortiz, J. Hernández, P. Clemente, and P. Amaya. ... [13] J. Stankovic, R. Zhu, R. Poornalingam, C. Lu, Z. Yu, M. Humphrey, and B. Ellis. Vest: An aspect-based composi-tion tool for real-time systems. ...
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We present the results of recent experiments and analysis on the polarization discrimination technique developed by us to separate elastic reflectance and fluorescence components resulting from white light illumination of algae in... more
We present the results of recent experiments and analysis on the polarization discrimination technique developed by us to separate elastic reflectance and fluorescence components resulting from white light illumination of algae in seawater. The technique uses the polarized properties of elastically scattered light and unpolarized properties of fluorescence to separate the two. The approach was successfully applied to measurements on
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As a result of rich nutrient and terrestrial influence dissolved organic matter plays an important role in determining the optical properties of coastal water. Despite the fact that the features of its fluorescence spectroscopy depend on... more
As a result of rich nutrient and terrestrial influence dissolved organic matter plays an important role in determining the optical properties of coastal water. Despite the fact that the features of its fluorescence spectroscopy depend on its complicated chemical components, which are source specific, estimation of solar stimulated CDOM fluorescence is usually based on a fixed Gaussian spectral shape or
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ABSTRACT An acquisition system was developed to measure the above water polarized radiance. This system consists of one irradiance sensor for downwelling irradiance, one radiance sensor oriented at 40° from the zenith to measure sky... more
ABSTRACT An acquisition system was developed to measure the above water polarized radiance. This system consists of one irradiance sensor for downwelling irradiance, one radiance sensor oriented at 40° from the zenith to measure sky radiance and three radiance sensors looking down at 40° from the nadir to measure above water radiance. In order to obtain the polarized radiance, polarizers with orientation of 0°, 90° and 45° respectively were placed in front of the three radiance sensors. The whole system was installed on the bow of the boat for continuous observations of above water polarized radiance along the ship's track during a recent cruise in the NY Bight area. Water optical properties were measured by an optical package towed from a small R/V. In order to obtain the degree of polarization (DOP) of the water body, the contribution of the sky radiance must be first removed and this process has to be done for all components of the Stokes vector. Using a model employing the polarized Fresnel coefficients of the interface the polarized component of reflection is estimated from the direct measurement of sky radiance and downwelling irradiance data. These components are then subtracted from the measured values to obtain the water contribution. The DOP of the ocean body is then related to the in - water IOPs.
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Multiangular, hyperspectral measurements of the underwater polarization light field, as well as comprehensive measurements of IOPs were collected in several cruise campaigns in the Chesapeake/Virginia area and New York Harbor/Hudson River... more
Multiangular, hyperspectral measurements of the underwater polarization light field, as well as comprehensive measurements of IOPs were collected in several cruise campaigns in the Chesapeake/Virginia area and New York Harbor/Hudson River areas. The waters examined were mostly eutropic water with Chlorophyll a concentration up to approximately 57 mug/L. It is found that Chlorophyll a fluorescence markedly impacts (reduces) the underwater degree of polarization (DOP) in the 650 - 700 nm spectral region. By taking note of the unpolarized nature of algal fluorescence and the partially polarized properties of elastic scattering, particularly by non-algal particles, we were able to separate the Chlorophyll a fluorescence signal from the total radiance. The analysis is based on comparisons of the underwater multiangular, hyperspectral polarization measurements which include fluorescence, compared with adding - doubling polarized radiative transfer simulations of elastic scattering which use measured IOPs as input, and which do not include fluorescence. The difference between the two shows the impact of fluorescence. These relationships are examined in detail, and the efficacy of using DOP measurements for underwater fluorescence retrieval is evaluated for different scattering geometries and water conditions.
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A general methodology for a spectroscopic continuous-wave, frequency-modulated ladar (CW-FM-ladar) concept based on principles of both CW-FM-range-finding and modulation spectroscopy, together with modern techniques of optical signal... more
A general methodology for a spectroscopic continuous-wave, frequency-modulated ladar (CW-FM-ladar) concept based on principles of both CW-FM-range-finding and modulation spectroscopy, together with modern techniques of optical signal transmission using tunable laser diodes, signal detection and heterodyne processing are presented. A mathematical description of trace gas detection using CW-LD ladar is developed including the relationship between the heterodyne echo-signal amplitudes and
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We present the results of recent experiments and analysis on the polarization discrimination technique developed by us to separate elastic reflectance and fluorescence components resulting from white light illumination of algae in... more
We present the results of recent experiments and analysis on the polarization discrimination technique developed by us to separate elastic reflectance and fluorescence components resulting from white light illumination of algae in seawater. The technique uses the polarized properties of elastically scattered light and unpolarized properties of fluorescence to separate the two. The approach was successfully applied to measurements on
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ABSTRACT The focus of this work is on the dependence of in situ hyperspectral and multiangular polarized data on the size distribution and refractive index of the suspended particles. Underwater polarization measurements were obtained... more
ABSTRACT The focus of this work is on the dependence of in situ hyperspectral and multiangular polarized data on the size distribution and refractive index of the suspended particles. Underwater polarization measurements were obtained using a polarimeter developed at the Optical Remote Sensing Laboratory of the City College of New York, NY. The degree of polarization (DOP) of the underwater light field in coastal environments was measured and the water-leaving polarized radiance was derived. In-water optical properties were also measured with an ac-9 (WET Labs). Absorption and attenuation spectra are then used to derive information on the dissolved and suspend components in the water medium which are used in a vector radiative transfer code which provides the upwelling radiance. The model was run for various values of the refractive index of mineral particles until the modeled DOP matched the measured one. The relationship between the intensity of the maximum of the DOP and both the refractive index of the mineral particles and the shapes of their size distributions is analyzed in detail.
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Determination of aerosol optical depth from satellite remote sensing measurements is extremely complex due to the large variability of aerosol optical properties. Significant simplification occurs when measurements are taken over water... more
Determination of aerosol optical depth from satellite remote sensing measurements is extremely complex due to the large variability of aerosol optical properties. Significant simplification occurs when measurements are taken over water since the ocean reflection signal can be taken ...
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In this paper we present a general methodology for a frequency-modulated ladar/lidar (CW-FM-ladar/lidar) concept based on principles of both CW-FM-range-finding and modulation spectroscopy, together with modern techniques of optical... more
In this paper we present a general methodology for a frequency-modulated ladar/lidar (CW-FM-ladar/lidar) concept based on principles of both CW-FM-range-finding and modulation spectroscopy, together with modern techniques of optical signal transmission using tunable laser diodes, signal detection and heterodyne processing. We develop a mathematical description of trace gas detection using CW-LD ladar developing the relationship between the heterodyne echo-signal amplitudes
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Abstract The collection 5 MODIS aerosol algorithm was designed to be more robust in handling surface reflection by differentiating different surfaces. When compared to the old collection 4 algorithm, we found that although there was some... more
Abstract The collection 5 MODIS aerosol algorithm was designed to be more robust in handling surface reflection by differentiating different surfaces. When compared to the old collection 4 algorithm, we found that although there was some improvement, the MODIS ...
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... of Automated Embedded Systems Olfa Mosbahi Loria, INRIA Lorraine Campus scientifique -BP 239-Vandoeuvre-Les-Nancy Email: olfa.mosbahi@loria.fr ... Let go and sel be two shared variables, go a command variable and ch is an exchange... more
... of Automated Embedded Systems Olfa Mosbahi Loria, INRIA Lorraine Campus scientifique -BP 239-Vandoeuvre-Les-Nancy Email: olfa.mosbahi@loria.fr ... Let go and sel be two shared variables, go a command variable and ch is an exchange one. ...
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The Long Island Sound Coastal Observational platform (LISCO) near Northport, New York, has been recently established to support satellite data validation. LISCO is equipped with both multispectral SeaPRISM and hyperspectral HyperSAS... more
The Long Island Sound Coastal Observational platform (LISCO) near Northport, New York, has been recently established to support satellite data validation. LISCO is equipped with both multispectral SeaPRISM and hyperspectral HyperSAS radiometers for ocean color measurements. LISCO substantially expands observational capabilities for the continuous monitoring and assessment of ocean color satellite data quality. This offers the potential for improving the
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The Long Island Sound Coastal Observational platform (LISCO) near Northport, New York, has been recently established to support satellite data validation. LISCO has both multispectral and hyperspectral radiometers for ocean color... more
The Long Island Sound Coastal Observational platform (LISCO) near Northport, New York, has been recently established to support satellite data validation. LISCO has both multispectral and hyperspectral radiometers for ocean color measurements. LISCO offers the potential for improving the calibration and validation activities of current and future Ocean Color satellite missions, as well as for satellite intercomparisons and spectral characterization
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Remote sensing of enemy installations or their movements by trace gas detection is a critical but challenging military objective. Open path measurements over ranges of a few meters to many kilometers with sensitivity in the parts per... more
Remote sensing of enemy installations or their movements by trace gas detection is a critical but challenging military objective. Open path measurements over ranges of a few meters to many kilometers with sensitivity in the parts per million or billion regime are crucial in anticipating the presence of a threat. Previous approaches to detect ground level chemical plumes, explosive constituents,
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In this paper we proposes a novel Passive Optical Network (PON) based broadband wireless access network architecture to provide multimedia services (video telephony, video streaming, mobile TV, mobile emails etc) to mobile users. In the... more
In this paper we proposes a novel Passive Optical Network (PON) based broadband wireless access network architecture to provide multimedia services (video telephony, video streaming, mobile TV, mobile emails etc) to mobile users. In the conventional wireless access networks, the base stations (Node B) and Radio Network Controllers (RNC) are connected by point to point T1/E1 lines (Iub interface). The
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Multimedia, Telecommunications, Video, Video Streaming, Quality of Service, and 12 morePassive Optical Networks, Broadband Wireless Access, Interfaces, Wireless Broadband, Network Architecture, Multimedia Services, Network Architectures, Wireless Access Network Deployment Strategy, Mobile Tv, Code Division Multiple Access, Graceful Degradation, and Base station
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Fluorescence Line Height (FLH) algorithms are effective for fluorescence retrieval in the open ocean where elastic reflectance in the fluorescence zone does not deviate much from the baseline. In coastal waters, FLH algorithms are... more
Fluorescence Line Height (FLH) algorithms are effective for fluorescence retrieval in the open ocean where elastic reflectance in the fluorescence zone does not deviate much from the baseline. In coastal waters, FLH algorithms are significantly complicated by the overlap of the fluorescence and elastic reflectance peaks. To test accuracy of MODIS, MERIS and other FLH algorithms, we compared numerical simulations
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... and Instrwnentation Engineering (I) INSAT: National Institute of Applied Science and Technology (2)ICOS: Research Unit on Intelligent Control, Design and Optimization of Complex System Tunis, Tunisia hamden _ bm ... T. BEN... more
... and Instrwnentation Engineering (I) INSAT: National Institute of Applied Science and Technology (2)ICOS: Research Unit on Intelligent Control, Design and Optimization of Complex System Tunis, Tunisia hamden _ bm ... T. BEN ROMDHANE(1), S. BEN AHMED (\, 3) (1,3) Dept. ...
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Modeling Quality Management System: A Multi-Agent Approach Hajer Ben Mahmoud, Raouf Ketata, Taeib Ben Romdhane, Samir Ben Ahmed INSAT, ICOS, Tunisia hamden_bm@yahoo. fr, raouf.ketata@insat.rnu.tn, tbr.tim@planet.tn,... more
Modeling Quality Management System: A Multi-Agent Approach Hajer Ben Mahmoud, Raouf Ketata, Taeib Ben Romdhane, Samir Ben Ahmed INSAT, ICOS, Tunisia hamden_bm@yahoo. fr, raouf.ketata@insat.rnu.tn, tbr.tim@planet.tn, samir.benahmed@fft.rnu.tn Abstract ...
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... and Instrumentation Engineering (I) INSAT: National Institute of Applied Science and Technology (2) ICOS: Research Unit on Intelligent Control, Design and Optimization of Complex System Tunis, Tunisia hamden _ bm ... T. BEN ROMDHANE... more
... and Instrumentation Engineering (I) INSAT: National Institute of Applied Science and Technology (2) ICOS: Research Unit on Intelligent Control, Design and Optimization of Complex System Tunis, Tunisia hamden _ bm ... T. BEN ROMDHANE (1), S. BEN AHMED (1, 3) (1.3) Dept. ...
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In this paper, we explore the performance of a bio-optical model used to estimate the water leaving radiance at 412nm and under what conditions this constraint can improve retrieval of water leaving radiances in the VIS and NIR channels.... more
In this paper, we explore the performance of a bio-optical model used to estimate the water leaving radiance at 412nm and under what conditions this constraint can improve retrieval of water leaving radiances in the VIS and NIR channels. We first demonstrate that the bio-optical model performance is well modeled by Hydrolight simulations under coastal water conditions and is particularly
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Abstract-The in-situ spectral data of water properties were collected throughout the Chesapeake Bay area during the 2005 summer cruise campaign. Measured quantities include absorption, attenuation, backscattering, reflectance and... more
Abstract-The in-situ spectral data of water properties were collected throughout the Chesapeake Bay area during the 2005 summer cruise campaign. Measured quantities include absorption, attenuation, backscattering, reflectance and fluorescence of chlorophyll and ...
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Variations of bidirectional reflectance effects in coastal waters are analyzed based on extensive radiative transfer simulations of remote sensing reflectances and field data, which are compared with existing models. Improved... more
Variations of bidirectional reflectance effects in coastal waters are analyzed based on extensive radiative transfer simulations of remote sensing reflectances and field data, which are compared with existing models. Improved relationships are proposed which better accounts for BRDF effects but should be further verified for a broader range of synthetic data with various sun, viewing and azimuth angles as well as insitu datasets.
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The authors suggest a specification and validation methodology of the production automated systems command. This method is backed by a hierarchical structuring of the command, which is expressed by “entities” provided with “functions” and... more
The authors suggest a specification and validation methodology of the production automated systems command. This method is backed by a hierarchical structuring of the command, which is expressed by “entities” provided with “functions” and intercommunicating by definite interfaces. The entity specification approach is based on the Ward and Mellor methodology of the real time structured analysis and the description of
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The use of multi-wavelength lidar measurements can in principle be used to estimate aerosol extinction and backscatter profiles. From the resultant multi-wavelength profiles, an estimate of particle size distribution parameters can be... more
The use of multi-wavelength lidar measurements can in principle be used to estimate aerosol extinction and backscatter profiles. From the resultant multi-wavelength profiles, an estimate of particle size distribution parameters can be inferred. However, the confidence of the retrieval depends on the accuracy of the retrieved backscatter and extinction coefficients. Conventional approaches determine errors by performing statistical calculations on the results of inversions of simulated measurements with errors derived from a random number generator. There is a certain ambiguity about the validity of this method which we try to resolve. We introduce two alternative methods. One is a reverse Monte-Carlo method which gives an ensemble of distribution parameters that produce simulated measurements whose inversions match the inversion of the retrieved measurements. Substantial differences in the results of the aforementioned methods were found. In order to clarify these differences, a semi-analytic approach is introduced that formulates the conditional probability density function of underlying particle size distribution parameters given a set of measurements (from the combined probability function with the underlying optical data). Results using the probability density function were found to be closer to the statistics of the reverse Monte-Carlo method than the conventional method.
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The purpose of this paper is to provide a path for designing a tool for decision support to ensure the effectiveness of Quality Management System (QMS). For this, we propose a Fuzzy-Neural Networks (FNN) approach for improving the... more
The purpose of this paper is to provide a path for designing a tool for decision support to ensure the effectiveness of Quality Management System (QMS). For this, we propose a Fuzzy-Neural Networks (FNN) approach for improving the efficiency of such system. The aim of this approach is to classify the objectives for a real-world case study which presents a
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Ajaz Sana, Gulistan Raja*, Shahab Hussain, Rashid N. Zaidi, Mohammed A. Ali, Samir Ahmed Dept of Electrical Engineering, Graduate School of the City University of Yew York 138th St &Convent Ave, New York, NY 10031, USA *Department of... more
Ajaz Sana, Gulistan Raja*, Shahab Hussain, Rashid N. Zaidi, Mohammed A. Ali, Samir Ahmed Dept of Electrical Engineering, Graduate School of the City University of Yew York 138th St &Convent Ave, New York, NY 10031, USA *Department of Electrical Engineering, University of ...
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The development of safe reconfigurable embedded control systems is a tremendous task since they must fulfill functional as well as safety requirements. In this paper the authors propose an agent-based approach to handle safe... more
The development of safe reconfigurable embedded control systems is a tremendous task since they must fulfill functional as well as safety requirements. In this paper the authors propose an agent-based approach to handle safe reconfigurations of control systems. The specification of the solution is covered by a set of UML-compliant metamodels. More specifically, the different software architectural configurations of the
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Abstract This paper proposes a novel Ethernet-based wired/wireless broadband access networking architecture that utilizes the existing wired trunk feeder fiber of typical PON (passive optical networks) infrastructure along with a hybrid... more
Abstract This paper proposes a novel Ethernet-based wired/wireless broadband access networking architecture that utilizes the existing wired trunk feeder fiber of typical PON (passive optical networks) infrastructure along with a hybrid FSO/RF (HFR), reliable wireless connectivity ...