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Relevant bibliographies by topics / Angular spectrum method

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Academic literature on the topic 'Angular spectrum method'

Author: Grafiati

Published: 6 September 2023

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Journal articles on the topic "Angular spectrum method"

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Shimobaba, Tomoyoshi, Kyoji Matsushima, Takashi Kakue, Nobuyuki Masuda, and Tomoyoshi Ito. "Scaled angular spectrum method." Optics Letters 37, no. 19 (September 28, 2012): 4128. http://dx.doi.org/10.1364/ol.37.004128.

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Wu, Sheng Jiang, Dang Juan Li, and Jin Jun Lu. "A New Method to Measure the Transmittance of Filter." Advanced Materials Research 383-390 (November 2011): 5309–14. http://dx.doi.org/10.4028/www.scientific.net/amr.383-390.5309.

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Based on the theory of Fabry-Perot interference, we analyzed the inherent relationship between single-wavelength and the spectrometry, established the mathematical model of transformation from angular spectrum measurement to spectral measurement,realized the data conversion between angular spectrum measurement and spectrum measurement; build the experimental platform and got the laser's transmittance by changing the incidence angle of the laser, and given the comparison experiment by using spectrophotometer, measured the spectral transmittance of filters. Comparison of the two measurement, the results show that:it is a feasible scheme that the angular spectrum measurement replace spectral measurement for filter transmittance .

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Schafer, Mark E., and Peter A. Lewin. "Transducer characterization using the angular spectrum method." Journal of the Acoustical Society of America 85, no. 5 (May 1989): 2202–14. http://dx.doi.org/10.1121/1.397869.

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Schafer, M. E., and P. A. Lewin. "Transducer characterization using the angular spectrum method." NDT & E International 25, no. 3 (1992): 152. http://dx.doi.org/10.1016/0963-8695(92)90423-e.

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Yan Zhao, Yan Zhao, Liangcai Cao Liangcai Cao, Hao Zhang Hao Zhang, Wei Tan Wei Tan, Shenghan Wu Shenghan Wu, Zheng Wang Zheng Wang, Qiang Yang Qiang Yang, and and Guofan Jin and Guofan Jin. "Time-division multiplexing holographic display using angular-spectrum layer-oriented method (Invited Paper)." Chinese Optics Letters 14, no. 1 (2016): 010005–10009. http://dx.doi.org/10.3788/col201614.010005.

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Peng, Bofang, Qixin Xu, and Wenmei Hou. "A novel overlay metrology method: Simultaneous utilizing spectral and angular spectrum." Optik 169 (September 2018): 228–35. http://dx.doi.org/10.1016/j.ijleo.2018.05.024.

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Arvanitis, Costas D., Calum Crake, Nathan McDannold, and Gregory T. Clement. "Passive Acoustic Mapping with the Angular Spectrum Method." IEEE Transactions on Medical Imaging 36, no. 4 (April 2017): 983–93. http://dx.doi.org/10.1109/tmi.2016.2643565.

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Hwang, Chi-Young, Seungtaik Oh, Il-Kwon Jeong, and Hwi Kim. "Stepwise angular spectrum method for curved surface diffraction." Optics Express 22, no. 10 (May 16, 2014): 12659. http://dx.doi.org/10.1364/oe.22.012659.

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Cheng, Qiu-Hu, Shi-Yu Wang, Meng-Yao Wu, Zhen Guo, De-Fang Cai, and Bing-Bin Li. "Nonuniform sampled angular spectrum method by using trigonometric interpolation." Chinese Physics B 27, no. 9 (September 2018): 094203. http://dx.doi.org/10.1088/1674-1056/27/9/094203.

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Kim, Yong-Hae, Chun-Won Byun, Himchan Oh, JaeWon Lee, Jae-Eun Pi, Gi Heon Kim, Myung-Lae Lee, Hojun Ryu, Hye-Yong Chu, and Chi-Sun Hwang. "Non-uniform sampling and wide range angular spectrum method." Journal of Optics 16, no. 12 (November 27, 2014): 125710. http://dx.doi.org/10.1088/2040-8978/16/12/125710.

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Dissertations / Theses on the topic "Angular spectrum method"

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Blasiak, Thomas C. "Modeling holographic grating imaging systems using the angular spectrum propagation method /." Link to online version, 2006. https://ritdml.rit.edu/dspace/handle/1850/2294.

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Li, Han. "Transfer Matrix Approach to Propagation of Angular Plane Wave Spectra Through Metamaterial Multilayer Structures." University of Dayton / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1324508726.

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Hadjara, Macinissa. "Observations et modélisations spectro-interférométriques longue base des étoiles et de leur environnement proche." Thesis, Nice, 2015. http://www.theses.fr/2015NICE4008/document.

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Cette thèse présente les résultats d'observations d'étoiles en rotation rapide menées sur le spectro-interféromètre AMBER du VLTI dans ses modes haute et moyenne résolutions spectrales. Les mesures effectuées sont les visibilités estimées sur trois bases simultanées, les phases différentielles en fonction de la longueur d'onde et des phases de clôtures avec, pour certaines nuits une bonne couverture du plan (u,v). Les données utilisées sont issues de plusieurs campagnes d'observation. Ces dernières étaient fortement dégradées par les défauts optiques d'AMBER, et affectés par des bruits classiques d'interférométrie optique à longue base en IR: défauts du détecteur, bruit de lecture, instabilités du suiveur de franges, ...etc. Leur analyse a nécessité la mise au point d'outils numériques de réduction spécifiques pour atteindre les précisions nécessaires à l'interprétation de mesures interférométriques. Pour interpréter ces mesures j'ai développé un modèle semi-analytique chromatique d'étoile en rotation rapide qui m'a permis d'estimer, à partir des phases différentielles; le degré d'aplatissement, le rayon équatorial, la vitesse de rotation, l'angle d'inclinaison, l'angle position de l'axe de rotation de l'étoile sur le ciel, la distribution de la température effective locale et de la gravité à la surface de l'étoile dans le cadre du théorème de von Zeipel. Les résultats concernant 4 étoiles massives de types spectraux B, A et F m'ont permis de les caractériser pour les mécanismes évoqués ci-dessus et d'ouvrir ainsi la perspective d'études plus systématiques d'objets similaires en étendant ultérieurement ces études à la relation photosphère-enveloppe circumstellaire
This thesis presents the results of rapidly rotating stars observations conducted on the AMBER spectro-interferometer VLTI in its high average spectral modes and resolutions. The measurements are estimated on three simultaneous visibility bases, differential phases depending on the wavelength and closure phases, with good coverage of the (u, v) plane for some nights. The data used are from several observation campaigns. These were highly degraded by the optical defects of AMBER, and assigned by standard optical interferometry long base IR noises: defects of the detector, reading noise, fringes follower instabilities, ... etc. Their analysis required the development of digital reduction of specific tools to achieve the necessary details to the interpretation of interferometric measurements. In interpreting these measures I developed a chromatic semi-analytical model of rapidly rotating star that allowed me to estimate, from the differential phases; the degree of flattening, the equatorial radius, speed of rotation, angle of inclination, the position angle of the star rotation axis in the sky, the local distribution of the actual temperature and the gravity to the surface of the star within the von Zeipel theorem. The results for four massive stars of spectral type B, A and F have allowed me to characterize the mechanisms discussed above and thus open framework for more systematic studies of similar objects subsequently extending these studies to the relationship photosphere circumstellar envelope

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Caumont-Prim, Chloé. "Détermination de la distribution de taille des nanoparticules de suie par analyse du spectre d'extinction et de diffusion angulaire de la lumière." Phd thesis, INSA de Rouen, 2013. http://tel.archives-ouvertes.fr/tel-00800137.

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Le but de ce travail est de déterminer par méthodes optiques la distribution de taille (pdf) des nanoparticules de suie, agrégats de morphologie fractale. Après des études préliminaires qui utilisent DDSCAT pour valider la théorie RDG-FA et permettent de convertir un rayon de giration en rayon de mobilité, deux diagnostics optiques sont étudiés. Le premier consiste à exploiter une mesure d'extinction spectrale de la lumière. Nous montrons que pour exploiter ce signal, il faut connaître les propriétés optiques des suies, leur préfacteur et dimension fractale, la loi de distribution et le diamètre des sphérules primaires. Le second diagnostic tire parti de la mesure angulaire de la diffusion de la lumière. Nous montrons qu'il est possible de déterminer la pdf à l'aide de la mesure de diffusion à trois angles. Il faut supposer la loi de distribution et la dimension fractale. Cette deuxième approche, in-situ, est plus appropriée que la première pour déterminer optiquement la pdf des suies.

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Morales, Mena Jorge. "Confined magnetohydrodynamics applied to magnetic fusion plasmas." Phd thesis, Ecole Centrale de Lyon, 2013. http://tel.archives-ouvertes.fr/tel-00995867.

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La description magnétohydrodynamique est utilisée pour étudier les plasmas de fusion par confinement magnétique dans deux configurations: tokamak et reversed field pinch. Une méthode de Fourier pseudo-spectrale et une technique de pénalisation en volume sont employées pour résoudre les équations. La méthode de pénalisation permet d'introduire des conditions aux limites de Dirichlet et donc de faire varier facilement la géométrie considérée. Les simulations dans des géométries toroïdales de type tokamak montrent l'apparition spontanée de vitesses. Une importante composante toroïdale se développe si le système est peu dissipatif. Il est aussi montré que la brisure de symétrie dans la forme de la section du tore fait apparaitre un moment angulaire toroïdal. Pour le Reversed Field Pinch on montre l'émergence de structures hélicoïdales. La forme de ces structures varie en fonction des coefficients de transport ainsi que du paramètre de pincement du champ magnétique imposé. Pour compléter l'étude on compare les résultats du tore aux calculs dans un cylindre périodique. Les différences dans la dynamique des deux cas sont mises en avant. Finalement les simulations sont confrontées à des expériences et un meilleur accord est observé entre simulation et expérience pour la géométrie toroïdale que pour la géométrie cylindrique.

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CHANG, WEI-KANG, and 張瑋剛. "Method and Implementation of Aliasing Reduced in Layered 3D Images Using Circular Iterative Angular Spectrum Algorithm (CIASA)." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/n8d42t.

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碩士
國立臺北科技大學
光電工程系
107
In the thesis, I present a method to generating layered three-dimensional (3D) images using the angular spectrum (AS) method and the experimental results of the four-layered 3D images implemented in spatial volumes. The AS method has the advantages in non-approximate solutions and simple calculations of diffraction wave propagation. The AS method was adopted in an iterative algorithm, called the iterative angular spectrum algorithm (IASA), to design individual diffractive optical elements (DOEs) for 3D layered images. In the previous research, the crosstalk noise between layers were not taken into account. In order to reduce the aliasing of four-layer mixing crosstalk, I proposed random interleaved sub-DOE method and circular iterative angular spectrum algorithm (CIASA) method to improve image quality. First, the 3D DOE was composed of four sub-DOEs (at distances of 125, 135, 145, and 155 mm) made the interleaved DOE. Sub-DOEs were generated by IASA and randomly interleaved using sub-DOE method for projecting two-dimensional (2D) images. Sub-DOEs were interleaved to constract a large DOE to display on a phase-modulation spatial light modulator and to produce four 2D diffraction images without using any optical imaging components. Final, I used CIASA to reduce the four-layer mixing crosstalk in interleaved DOE. The experiment results showed the four 2D images successfully constructed a layered 3D. Random interleaved sub-DOE method and CIASA method can make the image noise very low.

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HO, CHIH HUA. "Liquid crystals in woodpile photonic crystals: fabrication, numerical calculation and measurement." Doctoral thesis, 2016. http://hdl.handle.net/2158/1036656.

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Both experimental and numerical studies on Liquid Crystal (LC) infiltrated woodpile Photonic Crystal (PhC) are implemented in this thesis. The most well-known optical phenomenon of PhC is photonic bandgap (PBG). It is observed either in frequency or in spatial domain. The former means for a chromatic plane wave propagating though PhC that a range of frequencies do not transmit but reflect. The later means for a monochromatic focused beam passing though PhC that certain angular components do not transmit but deflect or reflect. The most well-investigated optical phenomenon of LC is birefringence. It is due to the strong dielectric anisotropy LC possesses. When the applied stimulations (e.g. electric/ optical field or external heater) are present, the orientation of LC molecules and different refractive indices (e.g. polarization or temperature dependent) are observed. The presence of LC inside PhC not only reduces index contrast (where angular BG appears) but also brings the tunability to such LC-PhC composite device. Therefore band-stop angular filter and sensitive refractometer for liquid material are potential applications controlled by multiple external stimulations. In this thesis, the related physical properties of PhCs and LCs are introduced beforehand. The fabrication of woodpile PhC is also demonstrated. Direct Laser Writing lithography technique is adopted to build microstructures with high resolution up to hundreds of nanometers. A tunable band-stop filter controlled by polarization and temperature is investigated in linear regime. To bridge our investigation to nonlinear regime, dye-doped LC is used to create graded indices inside LC medium corresponding to intensity. Numerical calculations are conducted to the experimental observations. To sum up, LC-PhC composite device possesses very promising features as demonstrated which could be applied into tunable elements in integrated optical systems and its abundant nonlinear properties remains to be explored carefully.

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Niu, Yaying. "Three-Dimensional Nonlinear Acoustical Holography." Thesis, 2013. http://hdl.handle.net/1969.1/149484.

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Nearfield Acoustical Holography (NAH) is an acoustic field visualization technique that can be used to reconstruct three-dimensional (3-D) acoustic fields by projecting two-dimensional (2-D) data measured on a hologram surface. However, linear NAH algorithms developed and improved by many researchers can result in significant reconstruction errors when they are applied to reconstruct 3-D acoustic fields that are radiated from a high-level noise source and include significant nonlinear components. Here, planar, nonlinear acoustical holography procedures are developed that can be used to reconstruct 3-D, nonlinear acoustic fields radiated from a high-level noise source based on 2-D acoustic pressure data measured on a hologram surface. The first nonlinear acoustic holography procedure is derived for reconstructing steady-state acoustic pressure fields by applying perturbation and renormalization methods to nonlinear, dissipative, pressure-based Westervelt Wave Equation (WWE). The nonlinear acoustic pressure fields radiated from a high-level pulsating sphere and an infinite-size, vibrating panel are used to validate this procedure. Although the WWE-based algorithm is successfully validated by those two numerical simulations, it still has several limitations: (1) Only the fundamental frequency and its second harmonic nonlinear components can be reconstructed; (2) the application of this algorithm is limited to mono-frequency source cases; (3) the effects of bent wave rays caused by transverse particle velocities are not included; (4) only acoustic pressure fields can be reconstructed. In order to address the limitations of the steady-state, WWE-based procedure, a transient, planar, nonlinear acoustic holography algorithm is developed that can be used to reconstruct 3-D nonlinear acoustic pressure and particle velocity fields. This procedure is based on Kuznetsov Wave Equation (KWE) that is directly solved by using temporal and spatial Fourier Transforms. When compared to the WWE-based procedure, the KWE-based procedure can be applied to multi-frequency source cases where each frequency component can contain both linear and nonlinear components. The effects of nonlinear bent wave rays can be also considered by using this algorithm. The KWE-based procedure is validated by conducting an experiment with a compression driver and four numerical simulations. The numerical and experimental results show that holographically-projected acoustic fields match well with directly-calculated and directly-measured fields.

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Tsai, Tsung Shiau, and 蔡宗孝. "Using Geant4 Monte Carlo methods to simulate the dose, fluence, energy spectrum and angular distribution of proton beam in water." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/66589504757362220708.

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碩士
長庚大學
醫學物理暨影像科學研究所
98
In this study, we use the Geant4 Monte Carlo simulation toolkit to simulate the 160 MeV proton beam dose, fluence, energy spectrum and angular distribution to discuss the proton beam characteristics. Before simulating the Geant4 Monte Carlo simulation, we have to define the geometry and the physics interaction process list. The physics interaction process list must consider the physics interaction processes that apply to proton therapy. Then we will compare the simulation dose results with proton stopping power and CSDA range that are provided by ICRU 49 tables. And the 160 MeV proton beam dose distribution results in water agree with the ICRU 49 tables. In this study, we also use the Geant4 to simulate the angular distribution in water phantom. We can find the proton beam scattered angles will increase with the depth in water phantom increase. Especially at the Bragg peak region, the proton beam scattered angle will increase fast. Otherwise we also can use the Gean4 Monte Carlo simulation toolkit to simulate the energy spectrum in different depth in water phantom.

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Books on the topic "Angular spectrum method"

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Adams, Charles S., and Ifan G. Hughes. Optics f2f. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198786788.001.0001.

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This book is primarily intended to be used in optics teaching from undergraduate to graduate level. It is assumed that an elementary course on optics has previously been studied, but all the key concepts of wave optics and light propagation are introduced where needed, and illustrated graphically. A recurring theme is that simple building blocks such as plane and spherical waves can be summed to construct useful solutions. Fourier methods and the angular-spectrum approach are used extensively, especially to provide a unified approach to Fraunhofer and Fresnel diffraction. Particular attention is paid to analysing topics in contemporary optics—propagation, dispersion, laser beams and waveguides, apodization, tightly focused vector fields, unconventional polarization states, and light–matter interactions. Throughout the text the principles are applied through worked examples and the book is copiously illustrated with more than 240 figures. The 200 end-of-chapter exercises offer further opportunities for testing the reader’s understanding.

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Rajeev, S. G. Hamiltonian Systems Based on a Lie Algebra. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198805021.003.0010.

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There is a remarkable analogy between Euler’s equations for a rigid body and his equations for an ideal fluid. The unifying idea is that of a Lie algebra with an inner product, which is not invariant, on it. The concepts of a vector space, Lie algebra, and inner product are reviewed. A hamiltonian dynamical system is derived from each metric Lie algebra. The Virasoro algebra (famous in string theory) is shown to lead to the KdV equation; and in a limiting case, to the Burgers equation for shocks. A hamiltonian formalism for two-dimensional Euler equations is then developed in detail. A discretization of these equations (using a spectral method) is then developed using mathematical ideas from quantum mechanics. Then a hamiltonian formalism for the full three-dimensional Euler equations is developed. The Clebsch variables which provide canonical pairs for fluid dynamics are then explained, in analogy to angular momentum.

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Book chapters on the topic "Angular spectrum method"

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Khare, Kedar. "The Angular Spectrum Method." In Fourier Optics and Computational Imaging, 145–51. Chichester, UK: John Wiley & Sons, Ltd, 2015. http://dx.doi.org/10.1002/9781118900352.ch10.

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Leeman, Sidney, and andrew J. Healey. "Field Propagation via the Angular Spectrum Method." In Acoustical Imaging, 363–68. Boston, MA: Springer US, 1997. http://dx.doi.org/10.1007/978-1-4419-8588-0_58.

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Rehman, Aziz U., C. Potel, and J. F. de Belleval. "Modeling of Ultrasonic Beam Interaction with an Anisotropic Multilayered Medium, Using Angular Spectrum Method." In Acoustical Imaging, 399–404. Boston, MA: Springer US, 1997. http://dx.doi.org/10.1007/978-1-4419-8588-0_63.

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Alagao, Mary Angelie, Mary Ann Go, Maricor Soriano, and Giovanni Tapang. "Characterization of the Performance of a 7-Mirror Segmented Reflecting Telescope via the Angular Spectrum Method." In Optics, Photonics and Laser Technology, 137–57. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-98548-0_7.

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Gamon, John A., Ran Wang, Hamed Gholizadeh, Brian Zutta, Phil A. Townsend, and Jeannine Cavender-Bares. "Consideration of Scale in Remote Sensing of Biodiversity." In Remote Sensing of Plant Biodiversity, 425–47. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-33157-3_16.

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AbstractA coherent and effective remote sensing (RS) contribution to biodiversity monitoring requires careful consideration of scale in all its dimensions, including spatial, temporal, spectral, and angular, along with biodiversity at different levels of biological organization. Recent studies of the relationship between optical diversity (spectral diversity) and biodiversity reveal a scale dependence that can be influenced by the RS methods used, vegetation type, and degree and nature of disturbance. To better understand these issues, we call for multi-scale field campaigns that test the effect of sampling scale, vegetation type, and degree of disturbance on the ability to detect different kinds of biodiversity, along with the development of improved models that incorporate both physical and biological principles as well as ecological and evolutionary theory. One goal of these studies would be to more closely match instrumentation and sampling scales to biological definitions of biodiversity and so improve optical diversity (spectral diversity) as a proxy for biodiversity. The ultimate goal would be to design and implement a truly effective, “scale-aware” global biodiversity monitoring system employing RS methods. Such a system could improve our understanding of the distribution and functional importance of biodiversity and enhance our ability to manage ecosystems for resilience and sustainability in a changing world.

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Khare, Kedar, Priyanka Lochab, and Paramasivam Senthilkumaran. "The angular spectrum method." In Orbital Angular Momentum States of Light. IOP Publishing, 2020. http://dx.doi.org/10.1088/978-0-7503-2280-5ch3.

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Schafer, Mark E. "The Angular Spectrum Method Of Transducer Characterization." In Ultrasonic Exposimetry, 257–82. CRC Press, 2020. http://dx.doi.org/10.4324/9780429272547-9.

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Vecchio, Christopher J., Peter A. Lewin, and Mark E. Schafer. "CHARACTERIZATION OF THE SURFACE VIBRATIONAL PATTERNS OF ACOUSTICALLY RADIATING STRUCTURES USING THE ANGULAR SPECTRUM METHOD." In Ultrasonics International 91, 327–30. Elsevier, 1991. http://dx.doi.org/10.1016/b978-0-7506-0389-8.50075-5.

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Charry, Edgar, and Daniel T. H. Lai. "Methods for Improving Foot Displacement Measurements Calculated from Inertial Sensors." In Biomedical Engineering and Information Systems, 93–116. IGI Global, 2011. http://dx.doi.org/10.4018/978-1-61692-004-3.ch005.

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The use of inertial sensors to measure human movement has recently gained momentum with the advent of low cost micro-electro-mechanical systems (MEMS) technology. These sensors comprise accelerometer and gyroscopes which measure accelerations and angular velocities respectively. Secondary quantities such as displacement can be obtained by integration of these quantities, a method which presents challenging issues due to the problem of accumulative sensor errors. This chapter investigates the spectral evaluation of individual sensor errors and looks at the effectiveness of minimizing these errors using static digital filters. The primary focus is on the derivation of foot displacement data from inertial sensor measurements. The importance of foot, in particular toe displacement measurements is evident in the context of tripping and falling which are serious health concerns for the elderly. The Minimum Toe Clearance (MTC) as an important gait variable for falls-risk prediction and assessment, and therefore the measurement variable of interest. A brief sketch of the current devices employing accelerometers and gyroscopes is presented, highlighting the problems and difficulties reported in literature to achieve good precision. These have been mainly due to the presence of sensor errors and the error accumulative process employed in obtaining displacement measurements. The investigation first proceeds to identify the location of these sensor errors in the frequency domain using the Fast Fourier Transform (FFT) on raw inertial sensor data. The frequency content of velocity and displacement measurements obtained from integrating the inertial data using a well known strap-down method is then explored. These investigations revealed that large sensor errors occurred mainly in the low frequency spectrum while white noise exists in all frequency spectra. The efficacy of employing a band-pass filter to remove a large portion of these errors and their effect on the derived displacements is elaborated on. The cross-correlation of the FFT power spectra from a highly accurate optical measurement system and processed sensor data is used as a metric to evaluate the performance of the band-pass filter at several stages of the processing stage. The motivation is that a more fundamental method would require less computational demand and could lead to more efficient implementations in low-power and systems with limited resources, so that portable sensor based motion measurement system would provide a good degree of measurement accuracy.

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Wang, Tao. "Perspective Chapter: Computational Modeling for Predicting the Optical Distortions through the Hypersonic Flow Fields." In Numerical Simulation [Working Title]. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.106591.

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Optical aberrations caused by supersonic/hypersonic flow files can lower the guidance accuracy of high-speed flying interceptors with onboard infrared guider. This chapter mainly summarizes the related research achievements on these issues based on the past works. First, the current developments on this important topic are discussed comprehensively. And secondly, the basic theories for predicting the aero-optical distortions used in this chapter, that is the computational flow field dynamics and its characteristics used for establishing the relationships with the flow fields and the optical light, are carefully provided. And then the density field of the flow field acquired from the large-eddy simulation (LES) can be transformed into the refractive index field in terms of the Gladstone-Dale relation. Recursive ray tracing method of optical propagation through the flow of fluids is given out. In the following, the chapter discusses the information optical modeling approach for the solutions to this issue. In the flow fields, every CFD grid is thought of as a uniform and isotropic cell. This chapter utilized the angular spectrum propagation theory for considering the optical waves propagating cell by cell. The suggested method can give out the optical transformation function (OTF), which can be directly used for modeling the aero-optical image. In the end, this chapter concludes the research works and points out the future development and potential applications of these presented research works.

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Conference papers on the topic "Angular spectrum method"

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Shimobaba, Tomoyoshi, Nobuyuki Masuda, and Tomoyoshi Ito. "Angular spectrum method for different sampling rates on source and destination planes: Scaled angular spectrum method." In Digital Holography and Three-Dimensional Imaging. Washington, D.C.: OSA, 2012. http://dx.doi.org/10.1364/dh.2012.dtu2c.3.

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Schafer, M. E., P. A. Lewin, and J. M. Reid. "Propagation Through Inhomogeneous Media Using the Angular Spectrum Method." In IEEE 1987 Ultrasonics Symposium. IEEE, 1987. http://dx.doi.org/10.1109/ultsym.1987.199099.

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Vecchio and Lewin. "Acoustic Propagation Modeling Using the Extended Angular Spectrum Method." In Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE, 1992. http://dx.doi.org/10.1109/iembs.1992.590508.

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Vecchio, Chris, and Peter A. Lewin. "Acoustic propagation modeling using the extended angular spectrum method." In 1992 14th Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE, 1992. http://dx.doi.org/10.1109/iembs.1992.5762211.

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Vyas, Urvi, and Douglas Christensen. "Ultrasound beam propagation using the hybrid angular spectrum method." In 2008 30th Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE, 2008. http://dx.doi.org/10.1109/iembs.2008.4649714.

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Wang, Zhaomin, Weijuan Qu, Fang Yang, Yongfu Wen, and Asundi Anand. "A new autofocus method based on angular spectrum method in digital holography." In The International Conference on Photonics and Optical Engineering and the Annual West China Photonics Conference (icPOE 2014), edited by Ailing Tian, Anand Asundi, Weiguo Liu, and Chunmin Zhang. SPIE, 2015. http://dx.doi.org/10.1117/12.2076853.

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Zhang, Wenhui, Hao Zhang, and Guofan Jin. "Band-extended angular spectrum method for resolution-enhanced digital holography." In Holography, Diffractive Optics, and Applications X, edited by Changhe Zhou, Yunlong Sheng, and Liangcai Cao. SPIE, 2020. http://dx.doi.org/10.1117/12.2573451.

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Etchepareborda, Pablo, Paul Connolly, Jan Henneberger, and Jonathan Crosier. "Distortion Free Angular Spectrum Method for Digital Inline Holographic Microscopy." In Digital Holography and Three-Dimensional Imaging. Washington, D.C.: Optica Publishing Group, 2022. http://dx.doi.org/10.1364/dh.2022.th2a.3.

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Abstract:

Compact Space-Bandwidth Angular Spectrum Method (CSW-ASM) is introduced for a high resolution reconstruction of digital in-line holograms with spherical wave illumination solving the distortion issue observed when using an ASM with planar reconstruction wave approach.

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Vecchio and Lewin. "Finite Amplitude Acoustic Propagation Modeling Using The Extended Angular Spectrum Method." In Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE, 1992. http://dx.doi.org/10.1109/iembs.1992.589784.

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Vecchio, Chris, and Peter A. Lewin. "Finite amplitude acoustic propagation modeling using the extended angular spectrum method." In 1992 14th Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE, 1992. http://dx.doi.org/10.1109/iembs.1992.5761005.

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